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Sample records for thermally dried kefir

  1. Kefir

    OpenAIRE

    Koçak, Celalettin; Gürsel, Asuman

    1981-01-01

    Kefir çok eski bir fermente süt mamülü olup, hammaddesi keçi, koyun ve inek sütüdür. %0.6-0.8 alkol içermesi nedeniyle fermente süt içkisi olarak tanınır. Günümüzde kefirin birçok hastalıklar üzerindeki iyileştirici etkisinden dolayı önemi artmıştır. Kefir üretiminde fermantasyonu sağlamak üzere kefir tanelerinden yararlanılır. Kefir taneleri sarımtırak renkte olup takriben bezelye büyüklüğündedir. Bu taneler kazein ve birbirleri ile ortaklaşa yaşayan mikroorganizmaların meydana getirdiği j...

  2. Kefir

    OpenAIRE

    Celalettin Koçak; Asuman Gürsel

    2015-01-01

    Kefir çok eski bir fermente süt mamülü olup, hammaddesi keçi, koyun ve inek sütüdür. %0.6-0.8 alkol içermesi nedeniyle fermente süt içkisi olarak tanınır. Günümüzde kefirin birçok hastalıklar üzerindeki iyileştirici etkisinden dolayı önemi artmıştır. Kefir üretiminde fermantasyonu sağlamak üzere kefir tanelerinden yararlanılır. Kefir taneleri sarımtırak renkte olup takriben bezelye büyüklüğündedir. Bu taneler kazein ve birbirleri ile ortaklaşa yaşayan mikroorganizmaların meydana getirdiği j...

  3. Kefir

    OpenAIRE

    Koçak, Celalettin; Gürsel, Asuman

    2014-01-01

    Kefir çok eski bir fermente süt mamülü olup, hammaddesi keçi, koyun ve inek sütüdür. %0.6-0.8 alkol içermesi nedeniyle fermente süt içkisi olarak tanınır. Günümüzde kefirin birçok hastalıklar üzerindeki iyileştirici etkisinden dolayı önemi artmıştır. Kefir üretiminde fermantasyonu sağlamak üzere kefir tanelerinden yararlanılır. Kefir taneleri sarımtırak renkte olup takriben bezelye büyüklüğündedir. Bu taneler kazein ve birbirleri ile ortaklaşa yaşayan mikroorganizmaların meydana getirdiği j...

  4. Kefir

    Directory of Open Access Journals (Sweden)

    Celalettin Koçak

    2015-02-01

    Full Text Available Kefir çok eski bir fermente süt mamülü olup, hammaddesi keçi, koyun ve inek sütüdür. %0.6-0.8 alkol içermesi nedeniyle fermente süt içkisi olarak tanınır. Günümüzde kefirin birçok hastalıklar üzerindeki iyileştirici etkisinden dolayı önemi artmıştır. Kefir üretiminde fermantasyonu sağlamak üzere kefir tanelerinden yararlanılır. Kefir taneleri sarımtırak renkte olup takriben bezelye büyüklüğündedir. Bu taneler kazein ve birbirleri ile ortaklaşa yaşayan mikroorganizmaların meydana getirdiği jelatinimsi kolonilerden oluşmuştur. Bu kolonilerin florasına bakteri ve mayalar hakimdir. Kefir üretiminde kullanılacak sütler homojenize ve ısıtma işlemlerine tabi tutulduktan sonra, kefir taneleri kullanılarak hazırlanan bulk starter ilave edilerek inkübasyona alınır. Bu evrede, laktik asit, alkol CO2 oluşmakta, kefir özel maya tat ve aroması kazanmaktadır. İnkübasyondan sonra olgunlaştırılarak paketlenen kefir tüketime sunulmaya hazır hale gelir.

  5. Survival of spray-dried Lactobacillus kefir is affected by different protectants and storage conditions.

    Science.gov (United States)

    Golowczyc, Marina A; Gerez, Carla L; Silva, Joana; Abraham, Analía G; De Antoni, Graciela L; Teixeira, Paula

    2011-04-01

    Survival of two Lactobacillus kefir strains after spray drying in reconstituted skim milk with or without the addition of 12.5 g monosodium glutamate/l, 20 g sucrose/l, or 20 g fructo-oligosaccharides (FOS)/l and during subsequent storage under different conditions of temperature (20 and 30°C) and relative humidity (RH) (0, 11 and 23%) was evaluated. After being dried, L. kefir 8321 and L. kefir 8348 had a decrease in viability of 0.29 and 0.70 log cfu/ml respectively, while the addition of different protectants improved the survival of both strains significantly. During storage, bacterial survival was significantly higher under lower conditions of RH (0-11%), and monosodium glutamate and FOS proved to be the best protectants.

  6. Comparison of chemical, rheological and sensory properties of kefir produced by kefir grains and commercial kefir starter

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    Irena Barukčić

    2017-01-01

    Full Text Available The main objective of this study was to compare chemical, rheological and sensory characteristics of kefir produced by using kefir grains and kefir starter. The intent was also to investigate whether it is plausible to use a combined inoculum (kefir grains and starter in order to obtain a kefir with improved characteristics in terms of sensory and rheological characteristics. Kefir samples were produced at 25 °C and 35 °C by using starter culture XPL-1, kefir grains and their combinations. All of the produced kefir samples were analysed for acidity, total dry matter, ethanol content, syneresis, viscosity and were sensory evaluated by a specially trained panel. There were no significant differences considering the total dry matter, syneresis, ethanol content and acidity. Excess viscosity was observed in samples produced by starter culture at 35 °C, which was described as untypical, yoghurt like and unsatisfactory by a sensory panel. The sample produced at 25 °C by equal amounts of kefir grains and starter culture received the highest scores at sensory evaluation and showed the best potential for optimizing the further use. Further investigations need to focus on examining kefir properties during the storage period, especially regarding microbiological and sensory properties, ethanol content and texture profile.

  7. Effect of freeze-drying on viability and in vitro probiotic properties of a mixture of lactic acid bacteria and yeasts isolated from kefir.

    Science.gov (United States)

    Bolla, Patricia A; Serradell, María de los Angeles; de Urraza, Patricio J; De Antoni, Graciela L

    2011-02-01

    The effect of freeze-drying on viability and probiotic properties of a microbial mixture containing selected bacterial and yeast strains isolated from kefir grains (Lactobacillus kefir, Lactobacillus plantarum, Lactococcus lactis, Saccharomyces cerevisiae and Kluyveromyces marxianus) was studied. The microorganisms were selected according to their potentially probiotic properties in vitro already reported. Two types of formulations were performed, a microbial mixture (MM) suspended in milk and a milk product fermented with MM (FMM). To test the effect of storage on viability of microorganisms, MM and FMM were freeze-dried and maintained at 4°C for six months. After 180 days of storage at 4°C, freeze-dried MM showed better survival rates for each strain than freeze-dried FMM. The addition of sugars (trehalose or sucrose) did not improve the survival rates of any of the microorganisms after freeze-drying. Freeze-drying did not affect the capacity of MM to inhibit growth of Shigella sonnei in vitro, since the co-incubation of this pathogen with freeze-dried MM produced a decrease of 2 log in Shigella viability. The safety of freeze-dried MM was tested in mice and non-translocation of microorganisms to liver or spleen was observed in BALB/c mice feed ad libitum during 7 or 20 days. To our knowledge, this is the first report about the effect of freeze-drying on viability, in vitro probiotic properties and microbial translocation of a mixture containing different strains of both bacteria and yeasts isolated from kefir.

  8. Microbial Diversity of a Camembert-Type Cheese Using Freeze-Dried Tibetan Kefir Coculture as Starter Culture by Culture-Dependent and Culture-Independent Methods

    Science.gov (United States)

    Mei, Jun; Guo, Qizhen; Wu, Yan; Li, Yunfei

    2014-01-01

    The biochemical changes occurring during cheese ripening are directly and indirectly dependent on the microbial associations of starter cultures. Freeze-dried Tibetan kefir coculture was used as a starter culture in the Camembert-type cheese production for the first time. Therefore, it's necessary to elucidate the stability, organization and identification of the dominant microbiota presented in the cheese. Bacteria and yeasts were subjected to culture-dependent on selective media and culture-independent polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE) analysis and sequencing of dominant bands to assess the microbial structure and dynamics through ripening. In further studies, kefir grains were observed using scanning electron microscopy (SEM) methods. A total of 147 bacteria and 129 yeasts were obtained from the cheese during ripening. Lactobacillus paracasei represents the most commonly identified lactic acid bacteria isolates, with 59 of a total of 147 isolates, followed by Lactococcus lactis (29 isolates). Meanwhile, Kazachstania servazzii (51 isolates) represented the mainly identified yeast isolate, followed by Saccharomyces cerevisiae (40 isolates). However, some lactic acid bacteria detected by sequence analysis of DGGE bands were not recovered by plating. The yeast S. cerevisiae and K. servazzii are described for the first time with kefir starter culture. SEM showed that the microbiota were dominated by a variety of lactobacilli (long and curved) cells growing in close association with a few yeasts in the inner portion of the grain and the short lactobacilli were observed along with yeast cells on the exterior portion. Results indicated that conventional culture method and PCR-DGGE should be combined to describe in maximal detail the microbiological composition in the cheese during ripening. The data could help in the selection of appropriate commercial starters for Camembert-type cheese. PMID:25360757

  9. Microbial diversity of a Camembert-type cheese using freeze-dried Tibetan kefir coculture as starter culture by culture-dependent and culture-independent methods.

    Directory of Open Access Journals (Sweden)

    Jun Mei

    Full Text Available The biochemical changes occurring during cheese ripening are directly and indirectly dependent on the microbial associations of starter cultures. Freeze-dried Tibetan kefir coculture was used as a starter culture in the Camembert-type cheese production for the first time. Therefore, it's necessary to elucidate the stability, organization and identification of the dominant microbiota presented in the cheese. Bacteria and yeasts were subjected to culture-dependent on selective media and culture-independent polymerase chain reaction (PCR-denaturing gradient gel electrophoresis (DGGE analysis and sequencing of dominant bands to assess the microbial structure and dynamics through ripening. In further studies, kefir grains were observed using scanning electron microscopy (SEM methods. A total of 147 bacteria and 129 yeasts were obtained from the cheese during ripening. Lactobacillus paracasei represents the most commonly identified lactic acid bacteria isolates, with 59 of a total of 147 isolates, followed by Lactococcus lactis (29 isolates. Meanwhile, Kazachstania servazzii (51 isolates represented the mainly identified yeast isolate, followed by Saccharomyces cerevisiae (40 isolates. However, some lactic acid bacteria detected by sequence analysis of DGGE bands were not recovered by plating. The yeast S. cerevisiae and K. servazzii are described for the first time with kefir starter culture. SEM showed that the microbiota were dominated by a variety of lactobacilli (long and curved cells growing in close association with a few yeasts in the inner portion of the grain and the short lactobacilli were observed along with yeast cells on the exterior portion. Results indicated that conventional culture method and PCR-DGGE should be combined to describe in maximal detail the microbiological composition in the cheese during ripening. The data could help in the selection of appropriate commercial starters for Camembert-type cheese.

  10. Microbiota of kefir grains

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    Tomislav Pogačić

    2013-03-01

    Full Text Available Kefir grains represent the unique microbial community consisting of bacteria, yeasts, and sometimes filamentous moulds creating complex symbiotic community. The complexity of their physical and microbial structures is the reason that the kefir grains are still not unequivocally elucidated. Microbiota of kefir grains has been studied by many microbiological and molecular approaches. The development of metagenomics, based on the identification without cultivation, is opening new possibilities for identification of previously nonisolated and non-identified microbial species from the kefir grains. Considering recent studies, there are over 50 microbial species associated with kefir grains. The aim of this review is to summarise the microbiota composition of kefir grains. Moreover, because of technological and microbiological significance of the kefir grains, the paper provides an insight into the microbiological and molecular methods applied to study microbial biodiversity of kefir grains.

  11. Oxygen and diverse nutrients influence the water kefir fermentation process.

    Science.gov (United States)

    Laureys, David; Aerts, Maarten; Vandamme, Peter; De Vuyst, Luc

    2018-08-01

    Eight water kefir fermentation series differing in the presence of oxygen, the nutrient concentration, and the nutrient source were studied during eight consecutive backslopping steps. The presence of oxygen allowed the proliferation of acetic acid bacteria, resulting in high concentrations of acetic acid, and decreased the relative abundance of Bifidobacterium aquikefiri. Low nutrient concentrations resulted in slow water kefir fermentation and high pH values, which allowed the growth of Comamonas testosteroni/thiooxydans. Further, low nutrient concentrations favored the growth of Lactobacillus hilgardii and Dekkera bruxellensis, whereas high nutrient concentrations favored the growth of Lactobacillus nagelii and Saccharomyces cerevisiae. Dried figs, dried apricots, and raisins resulted in stable water kefir fermentation. Water kefir fermentation with dried apricots resulted in the highest pH and water kefir grain growth, whereas that with raisins resulted in the lowest pH and water kefir grain growth. Further, water kefir fermentation with raisins resembled fermentations with low nutrient concentrations, that with dried apricots resembled fermentations with normal nutrient concentrations, and that with fresh figs or a mixture of yeast extract and peptone resembled fermentations with high nutrient concentrations. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. Some properties of kefir enriched with apple and lemon fiber

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    Busra Goncu

    2017-01-01

    Full Text Available The effects of apple and lemon fiber addition on some properties of kefir were investigated. Five different kefirs were produced (A is control, B, C, D, E, F and G: contain 0.25 % apple fiber, 0.5 % apple fiber, 1 % apple fiber, 0.25 % lemon fiber, 0.5 % lemon fiber and 1 % lemon fiber, respectively and stored for 20 days at 4±1 °C. pH, titratable acidity, dry matter, water activity, water holding capacity, viscosity, L, a and b values, sensorial analysis, total lactic bacteria, Lactococcus spp., Leuconostoc spp. and yeast counts of kefirs were determined at 1st, 10th and 20th days of storage. The addition of apple and lemon fiber enhanced rheological, microbiological and sensorial properties of kefirs (p<0.01. Apple and lemon fiber could be used for kefir production at a rate of 0.25 or 0.5 %.

  13. DIVERSIFIKASI KEFIR BERBASIS KEDELAI DENGAN VARIASI KONSENTRASI SUSU SKIM DAN INOKULUM

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    Tina Nurkhoeriyati*

    2017-12-01

    Full Text Available Physicochemical and sensory characteristics of commercial kefir were evaluated to be used as the benchmark for the development of soybean-based kefir with various concentrations of skim milk and inoculum. The commercial kefir has alcohol content and titratable acidity values in accordance with the Codex standards. A Quantitative Descriptive Analysis (QDA was carried out to obtain the description of kefir as the reference for the development of soybean-based kefir. Sensory evaluation of soybean-based kefir samples with various concentrations of skim milk and inoculum was conducted by trained panelists. Based on sensory evaluation, the soybean-based kefir with similar sensory characteristics to the commercial kefir was that made by adding 10% of skim milk and 10% kefir grains of 3, 4 and 5% (w/w. Soybean-based kefir with 10% (w/w skim milk and 3% (w/w kefir grains was chosen for analysis of its physicochemical characteristics. Despite having sensory characteristics similiar to commercial kefir, this soy-based kefir possesses different physicochemical properties from that of commercial one. Neverthe-less, the physico-chemical characteristics of selected kefir-based soybean met the Codex standards. The content of protein, fat, alcohol, dry matter and viscosity of the selected soy-based kefir were: 3.79±0.10% wb, 0.00±0.00% wb, 0.93±0.00%wb, 57.26 mg/kg, 8.43±0.38% wb, and 37.95±0.05 cP, respectively.

  14. Review: functional properties of kefir.

    Science.gov (United States)

    Guzel-Seydim, Zeynep B; Kok-Tas, Tugba; Greene, Annel K; Seydim, Atif C

    2011-03-01

    Kefir is a unique cultured dairy product due to combined lactic acid and alcoholic fermentation of lactose in milk. Kefir is produced by microbial activity of "kefir grains" which have a relatively stable and specific balance of lactic acid bacteria and yeast. Due to the claimed health benefits of kefir which include reduction of lactose intolerance symptoms, stimulation of the immune system, lowering cholesterol, and antimutagenic and anticarcinogenic properties, kefir has become an important functional dairy food and consequently, research on kefir has increased in the past decade. In the following review, recent studies on the functional properties of kefir are reviewed.

  15. Effect of using kefir in the formulation of traditional Tarhana

    OpenAIRE

    DEMIRCI, Ahmet Sukru; PALABIYIK, Ibrahim; OZALP, Seymanur; TIRPANCI SIVRI, Goksel

    2018-01-01

    Abstract Tarhana is known as a fermented cereal product made traditionally from wheat flour and yoghurt. As a novelty, kefir was used as substitute for yoghurt in tarhana production partially and completely to investigate the effects on fermentation activity, nutritional, sensory and rheological properties of tarhana. Addition of kefir increased the fermentation activity as raise in acidity values was observed compared to tarhana samples prepared with yoghurt. Regarding dry tarhana samples, ...

  16. Some properties of kefir enriched with apple and lemon fiber

    OpenAIRE

    Busra Goncu; Asli Celikel; Mutlu B. Guler-Akin; M. Serdar Akin

    2017-01-01

    The effects of apple and lemon fiber addition on some properties of kefir were investigated. Five different kefirs were produced (A is control, B, C, D, E, F and G: contain 0.25 % apple fiber, 0.5 % apple fiber, 1 % apple fiber, 0.25 % lemon fiber, 0.5 % lemon fiber and 1 % lemon fiber, respectively) and stored for 20 days at 4±1 °C. pH, titratable acidity, dry matter, water activity, water holding capacity, viscosity, L, a and b values, sensorial analysis, total lactic bacteria, Lactococcus ...

  17. ANTIOXIDANT POTENCY OF WATER KEFIR

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    Muneer Alsayadi M.S.

    2013-06-01

    Full Text Available Reactive oxygen species (ROS have strong relationship with several diseases. Many fermented foods were reported to be important sources for antioxidant compounds. Antioxidant activity of water kefir never reported in the scientific literature. The objective of this study was to detect and investigate the antioxidant potency of water kefir. Water kefir was prepared by fermentation of sugar solution with kefir grains for 24h. Antioxidant activity of fresh water kefir drink and its extract with (0.125–5 mg/ml was evaluated using 2,2,-diphenyl-1-pricrylhydrozyl (DPPH scavenging method, and inhibition of ascorbate autoxidation and the reducing power of water kefir were determined, Butylated hydroxyanisole (BHA and ascorbic acid were used for comparison. Water kefir demonstrated great ability to DPPH scavenging ranged (9.88-63.17%. And inhibit ascorbate oxidation by (6.08-25.57% increased in consequent with concentration raising. These results prime to conclude that water kefir could be promisor source of natural antioxidants with good potency in health developing.

  18. Kefir: a powerful probiotics with anticancer properties.

    Science.gov (United States)

    Sharifi, Mohammadreza; Moridnia, Abbas; Mortazavi, Deniz; Salehi, Mahsa; Bagheri, Marzieh; Sheikhi, Abdolkarim

    2017-09-27

    Probiotics and fermented milk products have attracted the attention of scientists from various fields, such as health care, industry and pharmacy. In recent years, reports have shown that dietary probiotics such as kefir have a great potential for cancer prevention and treatment. Kefir is fermented milk with Caucasian and Tibet origin, made from the incubation of kefir grains with raw milk or water. Kefir grains are a mixture of yeast and bacteria, living in a symbiotic association. Antibacterial, antifungal, anti-allergic and anti-inflammatory effects are some of the health beneficial properties of kefir grains. Furthermore, it is suggested that some of the bioactive compounds of kefir such as polysaccharides and peptides have great potential for inhibition of proliferation and induction of apoptosis in tumor cells. Many studies revealed that kefir acts on different cancers such as colorectal cancer, malignant T lymphocytes, breast cancer and lung carcinoma. In this review, we have focused on anticancer properties of kefir.

  19. Thermal analysis of cold vacuum drying of spent nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Piepho, M.G.

    1998-07-20

    The thermal analysis examined transient thermal and chemical behavior of the Multi canister Overpack (MCO) container for a broad range of cases that represent the Cold Vacuum Drying (CVD) processes. The cases were defined to consider both normal and off-normal operations at the CVD Facility for an MCO with Mark IV N, Reactor spent fuel in four fuel baskets and one scrap basket. This analysis provides the basis for the MCO thermal behavior at the CVD Facility for its Phase 2 Safety Analysis Report (revision 4).

  20. Physiochemical and Organoleptic Features of Goat Milk Kefir Made of Different Kefir Grain Concentration on Controlled Fermentation

    OpenAIRE

    Setyawardani, Triana; Rahardjo, Agustinus HD; Sulistyowati, Mardiati; Wasito, Samsu

    2014-01-01

    . Kefir mengandung bakteri dan ragi kompleks dalam protein dan matrik polisakarida yang terbentuk selama pertumbuhan anaerobic. Fermentasi kefir menggunakan biji kefir sebagai starter. Penelitian ini bertujuan mengkaji komposisi fisiokimiawi dan organoleptik kefir susu kambing yang terbuat dari biji kefir dengan konsentrasi berbeda pada fermentasi kontrol. Materi yang digunakan dua puluh tujuh liter susu kambing Peranakan Ettawah (PE) dan biji kefir. Penelitian menggunakan Rancangan Acak Leng...

  1. Thermal Transport Properties of Dry Spun Carbon Nanotube Sheets

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    Heath E. Misak

    2016-01-01

    Full Text Available The thermal properties of carbon nanotube- (CNT- sheet were explored and compared to copper in this study. The CNT-sheet was made from dry spinning CNTs into a nonwoven sheet. This nonwoven CNT-sheet has anisotropic properties in in-plane and out-of-plane directions. The in-plane direction has much higher thermal conductivity than the out-of-plane direction. The in-plane thermal conductivity was found by thermal flash analysis, and the out-of-plane thermal conductivity was found by a hot disk method. The thermal irradiative properties were examined and compared to thermal transport theory. The CNT-sheet was heated in the vacuum and the temperature was measured with an IR Camera. The heat flux of CNT-sheet was compared to that of copper, and it was found that the CNT-sheet has significantly higher specific heat transfer properties compared to those of copper. CNT-sheet is a potential candidate to replace copper in thermal transport applications where weight is a primary concern such as in the automobile, aircraft, and space industries.

  2. Comparison of the Antibacterial Activity of Cow Milk Kefir and Goat Milk Kefir Against Bacteria Bacillus Cereus

    OpenAIRE

    Suhartanti, Dwi; Septian, Ryan

    2014-01-01

    Background: Kefir is fermented milk and comes from the Caucasus. Kefir is made by inoculating cow milk, goat or sheep with kefir grain. Kefir contains 0.5–1.0% alcohol and 0.9 to 1.1% lactic acid. This product is very popular in the Soviet Union, where the consumption of kefir reach 4.5 kg per capita per year. Kefir made from pasteurized milk and fermented with kefir grain, kefir grain is white seeds from bacteria colony, such as Streptococcus sp., Lactobacilli and some types of yeast/yeast a...

  3. Thermal analysis of dry eye subjects and the thermal impulse perturbation model of ocular surface.

    Science.gov (United States)

    Zhang, Aizhong; Maki, Kara L; Salahura, Gheorghe; Kottaiyan, Ranjini; Yoon, Geunyoung; Hindman, Holly B; Aquavella, James V; Zavislan, James M

    2015-03-01

    In this study, we explore the usage of ocular surface temperature (OST) decay patterns to distinguished between dry eye patients with aqueous deficient dry eye (ADDE) and meibomian gland dysfunction (MGD). The OST profiles of 20 dry eye subjects were measured by a long-wave infrared thermal camera in a standardized environment (24 °C, and relative humidity (RH) 40%). The subjects were instructed to blink every 5 s after 20 ∼ 25 min acclimation. Exponential decay curves were fit to the average temperature within a region of the central cornea. We find the MGD subjects have both a higher initial temperature (p model, referred to as the thermal impulse perturbation (TIP) model. We conclude that long-wave-infrared thermal imaging is a plausible tool in assisting with the classification of dry eye patient. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Antimutagenic and antioxidant properties of milk-kefir and soymilk-kefir.

    Science.gov (United States)

    Liu, Je-Ruei; Chen, Ming-Ju; Lin, Chin-Wen

    2005-04-06

    This study was aimed at evaluating the antimutagenic and antioxidant properties of milk-kefir and soymilk-kefir. Such antimutagenic activity was determined by means of the Salmonella mutagenicity assay, whereas the antioxidant properties of kefir were evaluated by assessing the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity, lipid peroxidation inhibition activity, ferrous ion chelating ability, reducing power, and antioxidative enzyme activity. Both milk-kefir and soymilk-kefir demonstrated significantly greater antimutagenic activity than milk and soymilk. Milk-kefir and soymilk-kefir also displayed significantly greater scavenging activity upon DPPH radicals, an inhibition effect upon linoleic acid peroxidation, and more substantial reducing power but displayed a reduced glutathione peroxidase activity than was the case for milk and soymilk. Milk and soymilk fermented by kefir grains did not alter the ferrous ion chelating ability and superoxide dismutase activity of the original materials. These findings have demonstrated that milk-kefir and soymilk-kefir possess significant antimutagenic and antioxidant activity and suggest that milk-kefir and soymilk-kefir may be considered among the more promising food components in terms of preventing mutagenic and oxidative damage.

  5. Properties and benefits of kefir -A review

    Directory of Open Access Journals (Sweden)

    Stephen Moses John

    2015-06-01

    Full Text Available Kefir is becoming increasingly popular as a result of new research into its health benefits. It is a fermented milk drink which has its origin in the Caucasus Mountains of Russia. Kefir is prepared by inoculating milk with kefir grains which are a combination of bacteria and yeasts in a symbiotic matrix. The common microorganisms present are non-pathogenic bacteria, especially Lactobacillus sp. and yeasts. Kefir has a long history of health benefits in Eastern European countries. It is believed that kefir has therapeutic effects, thus it is important to study the various properties contained in, and exhibited by it. This review includes a critical revision of the antimicrobial, anti-carcinogenic, probiotic and prebiotic properties of kefir. Other health benefits, like reducing cholesterol and improving lactose tolerance are also discussed.

  6. POTENSI KEFIR SEBAGAI ANTIBAKTERI Propionibacterium acnes

    OpenAIRE

    ., Michael

    2015-01-01

    Jerawat merupakan suatu keadaan dimana pori-pori kulit tersumbat oleh kotoran dan adanya bakteri Propionibacterium acnes yang berkembang biak di daerah sumbatan tersebut. Di Indonesia, masyarakat mulai melirik suatu produk minuman yang dipercaya secara empiris dapat mengatasi masalah jerawat, yaitu produk minuman fermentasi kefir. Kefir merupakan produk fermentasi yang memiliki cita rasa asam dan sedikit beralkohol. Kefir dapat difermentasi dengan air maupun dengan susu. Kan...

  7. Milk kefir: nutritional, microbiological and health benefits.

    Science.gov (United States)

    Rosa, Damiana D; Dias, Manoela M S; Grześkowiak, Łukasz M; Reis, Sandra A; Conceição, Lisiane L; Peluzio, Maria do Carmo G

    2017-06-01

    Kefir is fermented milk produced from grains that comprise a specific and complex mixture of bacteria and yeasts that live in a symbiotic association. The nutritional composition of kefir varies according to the milk composition, the microbiological composition of the grains used, the time/temperature of fermentation and storage conditions. Kefir originates from the Caucasus and Tibet. Recently, kefir has raised interest in the scientific community due to its numerous beneficial effects on health. Currently, several scientific studies have supported the health benefits of kefir, as reported historically as a probiotic drink with great potential in health promotion, as well as being a safe and inexpensive food, easily produced at home. Regular consumption of kefir has been associated with improved digestion and tolerance to lactose, antibacterial effect, hypocholesterolaemic effect, control of plasma glucose, anti-hypertensive effect, anti-inflammatory effect, antioxidant activity, anti-carcinogenic activity, anti-allergenic activity and healing effects. A large proportion of the studies that support these findings were conducted in vitro or in animal models. However, there is a need for systematic clinical trials to better understand the effects of regular use of kefir as part of a diet, and for their effect on preventing diseases. Thus, the present review focuses on the nutritional and microbiological composition of kefir and presents relevant findings associated with the beneficial effects of kefir on human and animal health.

  8. Rapid detection of Lactobacillus kefiranofaciens in kefir grain and kefir milk using newly developed real-time PCR.

    Science.gov (United States)

    Kim, Dong-Hyeon; Chon, Jung-Whan; Kim, Hong-Seok; Yim, Jin-Hyeok; Kim, Hyunsook; Seo, Kun-Ho

    2015-04-01

    Lactobacillus kefiranofaciens is an indicator microorganism for kefir and a key factor in kefir grain formation and kefiran production. We designed a novel real-time PCR primer and probe set, LKF_KU504, for the rapid detection of L. kefiranofaciens. In inclusivity and exclusivity tests, only 14 L. kefiranofaciens strains were positive among 61 microorganisms, indicating 100 % sensitivity and specificity. The LKF_KU504 set also differentiated kefir milk from 30 commercial nonkefir yogurts. The levels of L. kefiranofaciens in kefir grain and kefir milk were significantly different, indicating L. kefiranofaciens was more concentrated in kefir grain than in kefir milk.

  9. EVALUATION OF THE ADDITION OF KEFIR DIET IN HOSPITAL

    OpenAIRE

    Martins, Joice de Fátima Laureano; Marinho, Eduarda; Firmino, Heloísa Helena; Rafael, Viviane da Cruz; Ferreira, Célia Lúcia de Luces Fortes

    2013-01-01

    Kefir grains are used in the preparation of a fermented milk product called kefir which. Its introduction in hospital diets promotes several benefits to patients and has great ability to stimulate the immune system. The objective was to verify the acceptance of different formulations with kefir as an ingredient. kefir grains (5%) were cultured for 24 hours at 22º C. Then, four formulations were prepared. Formulation 1 - 50% of kefir cultured in whole cow's milk with 50% strawberry pulp and sw...

  10. Kefir and health: a contemporary perspective.

    Science.gov (United States)

    Ahmed, Zaheer; Wang, Yanping; Ahmad, Asif; Khan, Salman Tariq; Nisa, Mehrun; Ahmad, Hajra; Afreen, Asma

    2013-01-01

    Kefir and its related products are renowned nutraceutical dairy products produced through fermentation of yeasts and bacteria naturally present in grains of kefir. The nutritional attributes of this self-carbonated beverage are due to presence of vital nutrients such as carbohydrates, proteins, minerals, vitamins, and some nutraceutical components. Antimicrobial activity, better gut health, anticarcinogenic activity, control on serum glucose and cholesterol, control on lactose intolerance and better immune system can be achieved through its regular consumption. Moreover, on the one side kefir is good dietetic beverage, and of particular interest of athletes, and on the other side the whole kefir is good for feeding small babies and pre-schoolers for good tolerance against disease and quick weight gain. Lots of works have been done on kefir from a health point of view. This study summarizes all the data that have been compiled to date. The purpose of this review is to gather information about microbiological, chemical, nutritional, and therapeutic aspects of kefir and kefir-like products to provide justification for its consumption. This review leads us to conclude that kefir begins a new dawn of food for the mankind.

  11. Kajian konsentrasi kefir grain dan lama simpan dalam refrigerator terhadap kualitas kimiawi kefir rendah lemak

    Directory of Open Access Journals (Sweden)

    Manik Eirry Sawitri

    2012-03-01

    Full Text Available Abstract : 1, 2percent (G2dan 3 percent (G3of milk volume and the second factor was storage time in refrigerator which were 0day(L0,7days(L7,14days(L14, 21 days(L21 and 28 days(L28 Keywords: kefir grains, storage time, refrigerator, low fat kefir . The variables measured were fat, protein, and alcohol content of kefir. Data were analyzed by analysis of variance and continued with Duncan. The results of research showed that concentration of kefir grains and storage time in refrigerator had highly significant effect (P0,05 on fat content of kefir. Interaction between both treatments had highly significant effect (P<0,01 on alcohol content of kefir. The conclusion of this research was apply 1 percent of kefir grains and maximum storage time in refrigerator for 21 days to produce kefir which appropriate with standard of fermentation milk. The objective of this research was to find out the influence of low fat milk in kefir processing with examined concentration on kefir grains and storage time in refrigerator to the fat, protein and alcohol content. This research was also to determined the concentration of kefir grains which appropriate to the standard of fermentation milk and as an information for practician and industry related to the research product. The materials used kefir that made from low fat milk (1% fat content, the research method was using Factorial Randomized Block Design (3X5. The first factor was concentration of kefir grains which were 1 percent(G

  12. Increasing thermal drying temperature of biosolids reduced nitrogen mineralisation and soil N2O emissions

    DEFF Research Database (Denmark)

    Case, Sean; Gomez Muñoz, Beatriz; Magid, Jakob

    2016-01-01

    . This will be of importance for the value of the biosolids when used to fertilise crops. We sourced AD biosolids from a Danish waste water treatment plant (WWTP) and dried it in the laboratory at 70, 130, 190 or 250 °C to >95 % dry matter content. Also, we sourced biosolids from the WWTP dried using its in-house thermal......Previous studies found that thermally dried biosolids contained more mineralisable organic nitrogen (N) than the raw or anaerobically digested (AD) biosolids they were derived from. However, the effect of thermal drying temperature on biosolid N availability is not well understood......) and N2O production was also the lowest in treatments of the highest drying temperature, suggesting that this material was more recalcitrant. Overall, thermal drying temperature had a significant influence on N availability from the AD biosolids, but drying did not improve the N availability...

  13. Dehydration and thermal inactivation of Lactobacillus plantarum WCFS1: Comparing single droplet drying to spray and freeze drying

    NARCIS (Netherlands)

    Perdana, J.A.; Bereschenko, L.A.; Fox, M.B.; Kuperus, J.H.; Kleerebezem, M.; Boom, R.M.; Schutyser, M.A.I.

    2013-01-01

    We demonstrated that viability loss during single droplet drying can be explained by the sum of dehydration and thermal inactivation. For Lactobacillus plantarum WCFS1, dehydration inactivation predominantly occurred at drying temperatures below 45 °C and only depended on the moisture content. Above

  14. Solar thermal drying of apricots: Effect of spectrally-selective cabinet materials on drying rate and quality metrics (abstract)

    Science.gov (United States)

    Solar thermal (ST) drying is currently not in widespread commercial use due to concerns about slow drying rates and poor product quality. ST dryer cabinets could be constructed from spectrally-selective materials (materials which transmit only certain sunlight wavelength bands), but these types of ...

  15. Kajian Konsentrasi Kefir Grain dan Lama Simpan dalam Refrigerator terhadap Kualitas Kimiawi Kefir Rendah Lemak

    OpenAIRE

    Sawitri, Manik Eirry

    2011-01-01

    1), 2percent (G2)dan 3 percent (G3)of milk volume and the second factor was storage time in refrigerator which were 0day(L0),7days(L7),14days(L14), 21 days(L21) and 28 days(L28 Keywords: kefir grains, storage time, refrigerator, low fat kefir). The variables measured were fat, protein, and alcohol content of kefir. Data were analyzed by analysis of variance and continued with Duncan. The results of research showed that concentration of kefir grains and storage time in refrigerator had highly...

  16. The water kefir grain inoculum determines the characteristics of the resulting water kefir fermentation process.

    Science.gov (United States)

    Laureys, D; De Vuyst, L

    2017-03-01

    To investigate the influence of the water kefir grain inoculum on the characteristics of the water kefir fermentation process. Three water kefir fermentation processes were started with different water kefir grain inocula and followed as a function of time regarding microbial species diversity, community dynamics, substrate consumption profile and metabolite production course. The inoculum determined the water kefir grain growth, the viable counts on the grains, the time until total carbohydrate exhaustion, the final metabolite concentrations and the microbial species diversity. There were always 2-10 lactic acid bacterial cells for every yeast cell and the majority of these micro-organisms was always present on the grains. Lactobacillus paracasei, Lactobacillus hilgardii, Lactobacillus nagelii and Saccharomyces cerevisiae were always present and may be the key micro-organisms during water kefir fermentation. Low water kefir grain growth was associated with small grains with high viable counts of micro-organisms, fast fermentation and low pH values, and was not caused by the absence of exopolysaccharide-producing lactic acid bacteria. The water kefir grain inoculum influences the microbial species diversity and characteristics of the fermentation process. A select group of key micro-organisms was always present during fermentation. This study allows a rational selection of a water kefir grain inoculum. © 2016 The Society for Applied Microbiology.

  17. BIOTECHNOLOGY FOR KEFIR WITH NEW QUALITIES

    Directory of Open Access Journals (Sweden)

    A. N. Ponomarev

    2014-01-01

    Full Text Available Summary. Modern kefir production is based on the milk acidification process with the use of kefir grains by alcohol and lactic acid fermentation. Casein large molecules are fermented by sourdough’ microorganisms, and as a result they are digested much more effectively by the body. Thanks to a special composition of the sourdough’ microbiota, which composed of yeast, lactic acid and acetic acid bacteria, kefir is especially useful for a person of any age, helps to restore energy balance of human body, beneficial effects on the nervous system and metabolic processes. On the basis of the traditional technology of kefir production, which includes processes of normalization, homogenization, pasteurization, cooling to a temperature of fermentation, injection of sourdough, has been developed kefir production technology with the introduction of the ferment transglyutaminase that provides the generation of its own lactoferrin by the composition of microorganisms in kefir grains. Lactoferrin content ranges from 500 to 1100 mg/l, which is considerably higher than in the control group (300 mg/l. Lactoferrin is natural antioxidant that prevents the effect of early aging of the organism, contributes to the preservation of a healthy gastrointestinal tract. In many ways lactoferrin contributes to the preservation of health and fully supports the active longevity.

  18. Kefir: a multifaceted fermented dairy product.

    Science.gov (United States)

    Nielsen, Barbara; Gürakan, G Candan; Unlü, Gülhan

    2014-12-01

    Kefir is a fermented dairy beverage produced by the actions of the microflora encased in the "kefir grain" on the carbohydrates in the milk. Containing many bacterial species already known for their probiotic properties, it has long been popular in Eastern Europe for its purported health benefits, where it is routinely administered to patients in hospitals and recommended for infants and the infirm. It is beginning to gain a foothold in the USA as a healthy probiotic beverage, mostly as an artisanal beverage, home fermented from shared grains, but also recently as a commercial product commanding shelf space in retail establishments. This is similar to the status of yogurts in the 1970s when yogurt was the new healthy product. Scientific studies into these reported benefits are being conducted into these health benefits, many with promising results, though not all of the studies have been conclusive. Our review provides an overview of kefir's structure, microbial profile, production, and probiotic properties. Our review also discusses alternative uses of kefir, kefir grains, and kefiran (the soluble polysaccharide produced by the organisms in kefir grains). Their utility in wound therapy, food additives, leavening agents, and other non-beverage uses is being studied with promising results.

  19. Evaluation of wound healing activities of kefir products.

    Science.gov (United States)

    Huseini, Hassan Fallah; Rahimzadeh, Golnar; Fazeli, Mohammad Reza; Mehrazma, Mitra; Salehi, Mitra

    2012-08-01

    Kefirs are natural probiotic compounds with antibacterial and anti-inflammatory properties which were tested in experimental burn injury. Kefir gels were prepared from an extract of continuously cultured kefir grains in MRS Broth medium for 24, 48 and 96h. Similar burn injuries were made on dorsal skin surface of 56 rats. After 24h the wounds were infected with Pseudomonas aeruginosa. The infected rats were divided in to 7 groups of 8 rats each. The base gel, silver sulfadiazine ointment, kefir 24h gel, kefir 48h gel, kefir 96h gel and kefir grains 96h gel were applied twice a day. Burn wound area was measured at baseline, one and two weeks. After two weeks the animals in all groups were sacrificed and whole skin wound areas were removed and percentage of epithelization, scar formation, inflammation and angiogenesis were evaluated. Results indicated that at the end of the 2nd week the percentage of wound size were lowest in order of kefir 96h gelkefir grains 96h gelkefir 48h gelkefir 24h gelkefir 96h gel, kefir grains 96h gel, kefir 48h gel, kefir 24h gel, silver sulfadiazine 1%, base gel and untreated groups. In conclusion the kefir gel therapy was an effective therapeutic approach to improve outcomes after severe burn as compared to conventional silver sulfadiazine treatment. Copyright © 2011 Elsevier Ltd and ISBI. All rights reserved.

  20. Solar thermal drum drying performance of prune and tomato pomaces

    Science.gov (United States)

    Fruit and vegetable pomaces are co-products of the food processing industry; they are underutilized in part because their high water activity (aw) renders them unstable. Drum drying is one method that can dry/stabilize pomaces, but current drum drying methods utilize conventional, high-environmental...

  1. "Petit suisse" cheese from kefir: an alternative dessert with microorganisms of probiotic activity

    Directory of Open Access Journals (Sweden)

    Thanise Sabrina Souza Santos

    2012-09-01

    Full Text Available "Petit Suisse" is a creamy cheese. Kefir is a symbiotic mixture of lactic acid bacteria and yeasts with probiotic activity including immunomodulation and balance of intestinal microflora. The present study aims to develop "Petit Suisse" cheese from kefir. Kefir grains were grown in pasteurized cow milk, and after the separation of kefir the serum was discarded and the "Petit Suisse" cheese was prepared using strawberry, mangaba, herbs, and dried tomatoes. The acceptance of the different preparations was evaluated using a nine-point hedonic scale followed by ANOVA. The sweet and salty products were compared by the Student's t-test. Purchase intent was evaluated by the means test and frequency distribution. All products were well accepted by the judges. The product was characterized by low yield, but it can be prepared at home at low cost. The nutritional composition analyses and the variety of flavors as well as the range of age of the judges are alternatives for further studies.

  2. Investigation Of Thermal Properties Of Naturally Seasoned Dry ...

    African Journals Online (AJOL)

    Steady-state thermal conductivity measurements of naturally seasoned African thorn tree (Macaranga barteri) timer boards were carried out. Other thermal and physical properties such as specific heat capacity, thermal resistivity, density, thermal absorptivity and diffusivity as well as percentage of dead air space (v/v) were ...

  3. Atividade anti-escherichia coli em kefir e soro de kefir tradicionais.

    Directory of Open Access Journals (Sweden)

    Simone Weschenfelder

    2009-06-01

    Full Text Available Através de Testes de Diluição em Sistema de Tubos Múltiplos determinou-se, in vitro, a Intensidade de Atividade de Inibição Bacteriana (IINIB/bacteriostasia e a Intensidade de Atividade de Inativação Bacteriana (IINAB/bactericidia de kefir e soro de kefir tradicionais, não submetidos a tratamento térmico, padronizados em relação ao tipo de leite e ao binômio tempo/temperatura de incubação e maturação, frente a inóculo padronizado de Escherichia coli (ATCC 11229 microrganismo indicador de interesse em alimentos. Kefir é um leite fermentado produzido pela adição de grãos de kefir ao leite, constituindo uma associação simbiótica entre bactérias ácido láticas, bactérias ácido acéticas e leveduras envoltas por uma matriz de polissacarídeos, o kefiran, enquanto o soro é o produto obtido da filtração do kefir. Tanto o kefir, quanto o soro de kefir apresentaram capacidade de inibição e inativação máximas sobre o inóculo bacteriano em concentrações < 108 UFC/mL.

  4. Glycemic index, insulinemic index, and satiety index of kefir.

    Science.gov (United States)

    Kong, Kai Ling; Hendrich, Suzanne

    2012-08-01

    To determine glycemic, insulinemic, and satiety indices of 3 types of kefir. This study was divided into 3 phases. In phase 1, 50 g of available carbohydrate from low-fat strawberry kefir or orange kefir was tested, and in phase 2, low-fat plain kefir containing 25 g of available carbohydrates was tested for glycemic index (GI), in both cases compared with an equivalent amount of glucose. In phase 3, 1000-kJ portions of all 3 types of kefirs were compared with white bread with the same energy content to determine the insulinemic index (II) and satiety index (SI) of all 3 kefirs. In all phases, a single-meal, randomized crossover design was performed in which the test meals were given to healthy adults, 5 men and 5 women. The total incremental plasma glucose area under the curve (iAUC) for strawberry, orange, and plain kefirs was significantly lower compared with the respective high-GI control food, which was glucose solution. However, the IIs and SIs of kefir did not differ significantly from the white bread. Kefir is a low- to moderate-GI food; however, its II was high. Although kefir had higher water content, the SI of kefir was not significantly different from white bread.

  5. Production and quality of kefir cultured butter

    Directory of Open Access Journals (Sweden)

    Yaşar Karaca

    2018-01-01

    Full Text Available Cream is the main raw material for the butter production and reflects its properties into butter quality. Maturation of cream with appropriate starter culture is important for butter quality, sensory properties and shelf life of the end product. Kefir grains contain important probiotics for healthy nutrition including lactic acid bacteria, acetic acid bacteria, and yeasts in high numbers. The aim of this research was to determine the properties of butter produced using natural kefir culture during a 21-day cold storage. Determination of microbial, chemical and sensory properties of butter samples was carried out. Control sample (KOTE had 6.64 log CFU g-1 Lactococcus spp. while kefir cultured butter samples had 8.58 log CFU g-1. Kefir cultured butter contained 5.24 log CFU g-1 L. acidophilus at Day 1, while control samples did not have L. acidophilus. Acetaldehyde content of kefir cultured butter was significantly higher from the uncultured butter. According to sensory evaluation performed by 12 panelists, KKTE samples had better sensory properties than those observed in the KOTE samples.

  6. Thermal safety analysis of a dry storage cask for the Korean standard spent fuel - 16159

    International Nuclear Information System (INIS)

    Cha, Jeonghun; Kim, S.N.; Choi, K.W.

    2009-01-01

    A conceptual dry storage facility, which is based on a commercial dry storage facility, was designed for the Korea standard spent nuclear fuel (SNF) and preliminary thermal safety analysis was performed in this study. To perform the preliminary thermal analysis, a thermal analysis method was proposed. The thermal analysis method consists of 2 parts. By using the method, the surface temperature of the storage canister corresponding to the SNF clad temperature was calculated and the adequate air duct area was decided using the calculation result. The initial temperature of the facility was calculated and the fire condition and half air duct blockage were analyzed. (authors)

  7. Effects of thermal drying on phosphorus availability from iron-precipitated sewage sludge

    DEFF Research Database (Denmark)

    Lemming, Camilla; Scheutz, Charlotte; Bruun, Sander

    2017-01-01

    sludge, and a triple superphosphate as a reference. Plant P availability was studied in a 197 d soil incubation experiment, with sampling for Diffusive Gradients in Thin films (DGT) and water extractable P (WEP) analyses over time, and in a pot experiment with spring barley (Hordeum vulgare L.). In both......, affects plant P availability after application to soil. The experiment included dewatered sewage sludge (20% DM) and thermally dried sewage sludge (95% DM) collected at a Danish wastewater treatment plant, as well as laboratory oven-dried (70, 130, 190, and 250°C; DM > 95%) subsamples of the dewatered...... experiments, thermal drying reduced P availability, as shown by 37 and 23% lower DGT and WEP values, respectively, and a 16% lower P uptake by barley in the pot experiment. The specific drying temperature did not appear to have much effect. Overall, our results suggest that thermal drying of iron...

  8. Effect of drying method on mechanical, thermal and water absorption properties of enzymatically crosslinked gelatin hydrogels

    Directory of Open Access Journals (Sweden)

    RAYSSA C. SIMONI

    Full Text Available ABSTRACT Enzymatically crossliked gelatin hydrogel was submitted to two different drying methods: air drying and freeze drying. The resulting polymeric tridimensional arrangement (compact or porous, respectively led to different thermal and swelling properties. Significant differences (p < 0.05 on thermal and mechanical characteristics as well as swelling in non-enzymatic gastric and intestinal simulated fluids (37 ºC were detected. Water absorption data in such media was modelled according to Higuchi, Korsmeyer-Peppas, and Peppas-Sahlin equations. Freeze dried hydrogel showed Fickian diffusion behavior while air dried hydrogels presented poor adjustment to Higuchi model suggesting the importance of the relaxation mechanism at the beginning of swelling process. It was possible to conclude that the same gelatin hydrogel may be suitable to different applications depending on the drying process used.

  9. Enhanced mechanical, thermal, and electric properties of graphene aerogels via supercritical ethanol drying and high-temperature thermal reduction.

    Science.gov (United States)

    Cheng, Yehong; Zhou, Shanbao; Hu, Ping; Zhao, Guangdong; Li, Yongxia; Zhang, Xinghong; Han, Wenbo

    2017-05-03

    Graphene aerogels with high surface areas, ultra-low densities and thermal conductivities have been prepared to exploit their wide applications from pollution adsorption to energy storage, supercapacitor, and thermal insulation. However, the low mechanical properties, poor thermal stability and electric conductivity restrict these aerogels' applications. In this paper, we prepared mechanically strong graphene aerogels with large BET surface areas, low thermal conductivities, high thermal stability and electric conductivities via hydrothermal reduction and supercritical ethanol drying. Annealing at 1500 °C resulted in slightly increased thermal conductivity and further improvement in mechanical properties, oxidation temperature and electric conductivity of the graphene aerogel. The large BET surface areas, together with strong mechanical properties, low thermal conductivities, high thermal stability and electrical conductivities made these graphene aerogels feasible candidates for use in a number of fields covering from batteries to sensors, electrodes, lightweight conductor and insulation materials.

  10. Acquisition of the yeast Kluyveromyces marxianus from unpasteurised milk by a kefir grain enhances kefir quality.

    Science.gov (United States)

    Gethins, Loughlin; Rea, Mary C; Stanton, Catherine; Ross, R Paul; Kilcawley, Kieran; O'Sullivan, Maurice; Crotty, Suzanne; Morrissey, John P

    2016-08-01

    Kefir is a fermented milk beverage consumed for nutritional and health tonic benefits in many parts of the world. It is produced by the fermentation of milk with a consortium of bacteria and yeast embedded within a polysaccharide matrix. This consortium is not well defined and can vary substantially between kefir grains. There are little data on the microbial stability of kefir grains, nor on interactions between microbes in the grain and in the milk. To study this, a grain was split, with one half of each stored at -20°C and the other half passaged repeatedly in whole unpasteurised milk. Grains passaged in the unpasteurised milk recovered vigour and acquired the yeast Kluyveromyces marxainus from the milk which was confirmed to be the same strain by molecular typing. Furthermore, these passaged grains produced kefir that was distinguished chemically and organoleptically from the stored grains. Some changes in ultrastructure were also observed by scanning electron microscopy. The study showed that kefir grains can acquire yeast from their environment and the final product can be influenced by these newly acquired yeasts. Kluyveromyces marxianus is considered to be responsible for some of the most important characteristics of kefir so the finding that this yeast is part of the less stable microbiota is significant. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Rodigo Uno (Italy) geothermal thermal energy for crop drying

    International Nuclear Information System (INIS)

    Facchini, U.; Sordelli, C.; Magnoni, S.; Cantadori, M.

    1992-01-01

    This paper outlines the chief design and performance features of a forage drying installation which makes use of locally available geothermal energy. The heat exchange is accomplished through a water-air exchanger directly fed by 59 degrees C geothermal springs. Two 80,000 cubic meter/hour ventilators, making use of this energy (58 to 38 degrees C heat exchange), raise the drying air temperature by 16 degrees C, while providing an overall drying capacity of 43,200 kg/day. The balance of available 38 degrees C geothermal energy is being employed by a local aquaculture farm. The paper comments on the economic and environmental benefits being derived from this direct utilization of geothermal energy

  12. The evaluation of kefir pure culture starter: Liquid-core capsule entrapping microorganisms isolated from kefir grains.

    Science.gov (United States)

    Wang, Liang; Zhong, Hao; Liu, Keying; Guo, Aizhen; Qi, Xianghui; Cai, Meihong

    2016-10-01

    The main purpose of this study was to develop a pure culture starter for producing kefir. In order to accomplish starter recycling, yeasts (Kluyveromyces marxianus strain, Pichia kudriavzevii clone), lactic acid bacteria (Lactobacillus kefiri strain F4Aa, Lactobacillus kefiri strain NM131-7, Lactobacillus kefiri strain NM132-3, Lactobacillus kefiri strain NM180-3, respectively), and acetic acid bacteria (Acetobacter lovaniensis strain) were entrapped in liquid core capsules based on the distribution ratio in kefir grains. The microbiological, antimicrobial, and chemical properties of kefir made with capsules (M) and kefir grains (K) were measured and compared. According to the results of plate counts in different selective medium, the number of yeasts and bacteria in the liquid core capsules gradually increased and stabilized after eight fermentation cycles. The results of gas chromatography-mass spectrometry showed that almost all the aroma components existed in the two type of kefir, except the ethyl lactate. There was no significant difference in alcohol content, protein content, and fat content, except the acidity and sugar content. Water holding capacity of kefir K was higher than kefir M. There were 14 same free amino acids in kefir M and kefir K, and the content of most free amino acids was similar. In antimicrobial test, there was no significant difference in both kefirs. © The Author(s) 2016.

  13. Dry processing versus dense medium processing for preparing thermal coal

    CSIR Research Space (South Africa)

    De Korte, GJ

    2013-10-01

    Full Text Available environmental impact is taken into consideration. The main consideration when implementing dry processing, especially for long-term projects, is whether the low cost of the process will be outweighed by the low recovery efficiency. This paper gives an overview...

  14. EVALUATION OF THERMAL EFFICIENCY OF THE TECHNOLOGICAL SCHEME OF APPLE CHIPS AND DRIED FRUITS PRODUCTION

    Directory of Open Access Journals (Sweden)

    G. V. Kalashnikov

    2014-01-01

    Full Text Available The estimation of thermodynamic perfection of separate technological processes is executed at heat-moisture of handling of fruit and a line of manufacture of fruit apple chips and dried fruits. The technological scheme of a line of processing of fruits and manufactures of fruit chips on the basis of convection and the microwave-dryings suggested resource-saving. The technique is made and results of calculation of thermal expenses for various schemes of manufacture of apple chips are resulted. For the offered scheme material, thermal and power streams on the basis of balance parities of technological processes are certain. The comparative thermal production efficiency of apple chips for a base foreign variant and the offered technological scheme with the closed cycle of use of the heat-carrier and the combined convection-microwave-drying is shown. In this paper we define the thermal and energy flows for the processes of convective drying, pre-microwave drying, hydrothermal treatment and final microwave drying plant material, which are one of the main stages of the production of all kinds of fruit and vegetable concentrates, including fruit apple chips. Resource-saving ways moisture-heat of handling (hydration, blanching, drying, etc. produce raw materials in the production of food concentrates suggested a reduced water flow with a high degree of use of its potential power and microwave sources. To assess the thermal efficiency of the various processes and production schemes used as indicators of thermal efficiency and proposed value of specific heat (kJ / kg given mass productivity per unit of feedstock and translational moisture. The values of the mass fraction of the heat of material flows for the base and the proposed resource-saving production scheme fruit chips, for example, apple, based on a combination of convection-microwave drying each control surface.

  15. Milk kefir: composition, microbial cultures, biological activities, and related products.

    Science.gov (United States)

    Prado, Maria R; Blandón, Lina Marcela; Vandenberghe, Luciana P S; Rodrigues, Cristine; Castro, Guillermo R; Thomaz-Soccol, Vanete; Soccol, Carlos R

    2015-01-01

    In recent years, there has been a strong focus on beneficial foods with probiotic microorganisms and functional organic substances. In this context, there is an increasing interest in the commercial use of kefir, since it can be marketed as a natural beverage that has health promoting bacteria. There are numerous commercially available kefir based-products. Kefir may act as a matrix in the effective delivery of probiotic microorganisms in different types of products. Also, the presence of kefir's exopolysaccharides, known as kefiran, which has biological activity, certainly adds value to products. Kefiran can also be used separately in other food products and as a coating film for various food and pharmaceutical products. This article aims to update the information about kefir and its microbiological composition, biological activity of the kefir's microflora and the importance of kefiran as a beneficial health substance.

  16. Inhibition of Bacillus cereus in milk fermented with kefir grains.

    Science.gov (United States)

    Kakisu, Emiliano J; Abraham, Analía G; Pérez, Pablo F; De Antoni, Graciela L

    2007-11-01

    The effects of kefir-fermented milk were tested against a toxigenic strain of Bacillus cereus. The incubation of milk with B. cereus spores plus 5% kefir grains prevented spore germination and growth of vegetative forms. In contrast, when 1% kefir grains was used, no effects were observed. The presence of metabolically active kefir grains diminished titers of nonhemolytic enterotoxin A, as assessed by enzyme-linked immunosorbent assay. During fermentation, kefir microorganisms produce extracellular metabolites such as organic acids, which could play a role in the inhibition of spore germination and growth of B. cereus, although the effect of other factors cannot be ruled out. Results of the present study show that kefir-fermented milk is able to antagonize key mechanisms involved in the growth of B. cereus as well as interfere with the biological activity of this microorganism.

  17. Thermal inactivation of eight Salmonella serotypes on dry corn flour.

    OpenAIRE

    VanCauwenberge, J E; Bothast, R J; Kwolek, W F

    1981-01-01

    Dry heat was used to inactivate Salmonella newington, Salmonella typhimurium, Salmonella anatum, Salmonella kentucky, Salmonella cubana, Salmonella seftenberg, Salmonella thompson, and Salmonella tennessee in corn flour at 10 and 15% moisture. The flour was spray inoculated at 10(5) Salmonella cells per g and then stored at 49 degrees C (120 degrees F); viable Salmonella cells were counted on Trypticase (BBL Microbiology Systems) soy agar plates every 30 min for the first 4 h and then at 4-h ...

  18. Optimization of solar thermal dryer designs for the production of sun-dried apricots (Prunus armeniaca)(abstract)

    Science.gov (United States)

    Solar thermal (ST) drying is a ubiquitous method that has had widespread use for fruit and vegetable crop preservation in developing countries. Conversely, in the United States solar thermal drying has found limited commercialization due to concerns about slow drying rates and poor product quality. ...

  19. The antiallergic effect of kefir Lactobacilli.

    Science.gov (United States)

    Hong, Wei-Sheng; Chen, Yen-Po; Chen, Ming-Ju

    2010-10-01

    This study demonstrated that oral feeding of heat-inactivated Lactobacillus (L b.) kefiranofaciens M1 from kefir grains effectively inhibited immunoglobulin (Ig) E production in response to ovalbumin (OVA) in vivo. The pattern of cytokine production by splenocyte cells revealed that the levels of cytokines produced by T helper (Th) 1 cells increased, and those of cytokines produced by Th2 cells decreased in the heat-inactivated M1 feeding group. These findings indicated that Lactobacillus kefiranofaciens M1 in the kefir played an important role in antiallergic activities. By additional analysis using flow cytometry and microarray, the mechanism of suppression of IgE production by oral feeding of the heat-inactivated M1 probably occurs because of upregulation of the expression of Cd2, Stat4, and Ifnr leading to skewing the Th1/Th2 balance toward Th1 dominance, elevation of the CD4(+)CD25(+) regulatory T (Treg) percentage, and reduction of activated CD19(+) B cells. Downregulation of complement system and components was also involved in suppression of IgE production. Practical Application: Kefir has long been considered good for health. Its health benefits include immunoregulatory effects. However, there is a lack of knowledge concerning the immunoregulatory effects induced by kefir lactic acid bacteria (LAB). Our data clearly demonstrated the antiallergic activity of kefir LAB, Lactobacillus (L b.) kefiranofaciens M1. By additional analysis using flow cytometry and microarray, the possible mechanism of suppression of IgE production by oral feeding of the heat-inactivated M1 was also elucidated. Our findings indicated that Lactobacillus kefiranofaciens M1 may have a great potential for utilization in functional food products.

  20. Microbes of fermented kefir-like using combination of kefir grains and Bifidobacterium longum

    Directory of Open Access Journals (Sweden)

    Sri Usmiati

    2005-03-01

    Full Text Available The objectives of research were to find out physico-chemical characters and to detect flavor volatile compound of kefir-like. Material used was skim milk TS 9.5% which was heated at 85oC for 30 minutes and cooled at 22oC before innoculation of the starter. Microorganisms used were (a Lactobacillus acidophilus P155110, (b Lactobacillus delbrueckii subsp. Bulgaricus NCIMB 11778, (c Lactococcus lactis P155610, (d Leuconostoc mesenteroides subsp. dextranicum NCIMB 3350, (e Acetobacter aceti P154810, (f Bifidobacterium longum BF1, and (g Saccharomyces cerevisiae P156252. The treatments consist of P1 = without (b; P2 = without (a; and P3= used (a until (g. The physico-chemical characters identified were lactic acid and lactose percentages, pH, viscosity, organoleptic test for intensity of kefir-like sensory attributes. Results indicated that B. longum was potential bacterium use for starter combination on kefir-like making. The use starter P1 combination has high acidity and viscosity, low pH and lactose percentage, and high intensity on attribute creamy-white color, soft and curdle consistency, and kefir specific aroma on kefir-like. Volatile compound acid group were dominate by high acidity character on kefir-like resulted from starter P1 combination. Compound of 3-hydroxi-2-butanone (acetoin was affecting butter-like of P3 character. This compound resulted from which is a character of fermented milk flavor was not detected on P1 kefir-like.

  1. Thermal Aggregation of Calcium-Fortified Skim Milk Enhances Probiotic Protection during Convective Droplet Drying.

    Science.gov (United States)

    Wang, Juan; Huang, Song; Fu, Nan; Jeantet, Romain; Chen, Xiao Dong

    2016-08-03

    Probiotic bacteria have been reported to confer benefits on hosts when delivered in an adequate dose. Spray-drying is expected to produce dried and microencapsulated probiotic products due to its low production cost and high energy efficiency. The bottleneck in probiotic application addresses the thermal and dehydration-related inactivation of bacteria during process. A protective drying matrix was designed by modifying skim milk with the principle of calcium-induced protein thermal aggregation. The well-defined single-droplet drying technique was used to monitor the droplet-particle conversion and the protective effect of this modified Ca-aggregated milk on Lactobacillus rhamnosus GG. The Ca-aggregated milk exhibited a higher drying efficiency and superior protection on L. rhamnosus GG during thermal convective drying. The mechanism was explained by the aggregation in milk, causing the lower binding of water in the serum phase and, conversely, local concentrated milk aggregates involved in bacteria entrapment in the course of drying. This work may open new avenues for the development of probiotic products with high bacterial viability and calcium enrichment.

  2. Spray freeze-dried nanofibrillated cellulose aerogels with thermal superinsulating properties.

    Science.gov (United States)

    Jiménez-Saelices, Clara; Seantier, Bastien; Cathala, Bernard; Grohens, Yves

    2017-02-10

    Nanofibrillated cellulose (NFC) aerogels were prepared by spray freeze-drying (SFD). Their structural, mechanical and thermal insulation properties were compared to those of NFC aerogels prepared by conventional freeze-drying (CFD). The purpose of this investigation is to develop superinsulating bioaerogels by reducing their pore size. Severe reduction of the aerogel pore size and skeleton architecture were observed by SEM, aerogels prepared by SFD method show a fibril skeleton morphology, which defines a mesoporous structure. BET analyses confirm the appearance of a new organization structure with pores of nanometric sizes. As a consequence, the thermal insulation properties were significantly improved for SFD materials compared to CFD aerogel, reaching values of thermal conductivity as low as 0.018W/(mK). Moreover, NFC aerogels have a thermal conductivity below that of air in ambient conditions, making them one of the best cellulose based thermal superinsulating material. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Numerical Simulation of the Thermal Performance of a Dry Storage Cask for Spent Nuclear Fuel

    Directory of Open Access Journals (Sweden)

    Heui-Yung Chang

    2018-01-01

    Full Text Available In this study, the heat flow characteristics and thermal performance of a dry storage cask were investigated via thermal flow experiments and a computational fluid dynamics (CFD simulation. The results indicate that there are many inner circulations in the flow channel of the cask (the channel width is 10 cm. These circulations affect the channel airflow efficiency, which in turn affects the heat dissipation of the dry storage cask. The daily operating temperatures at the top concrete lid and the upper locations of the concrete cask are higher than those permitted by the design specification. The installation of the salt particle collection device has a limited negative effect on the thermal dissipation performance of the dry storage cask.

  4. A critical investigation into the spray-drying of hydroxyapatite powder for thermal spray applications

    OpenAIRE

    Murtaza, Qasim

    2006-01-01

    This work examines the investigation of the spray drying process of Hydroxyapatite powder (HA) used as a thermal spray deposit in the application of orthopaedic femoral implants. In this research, the Niro- Minor™ mixed spray dryer was used for both modelling and experimental studies. The process parameters investigated included HA slurry viscosity, temperature, and air flowrate. Computational Fluid Dynamic (CFD) modelling and validation of the spray drying of HA powder was performed. An anal...

  5. The thermal insulation difference of clothing ensembles on the dry and perspiration manikins

    International Nuclear Information System (INIS)

    Xiaohong, Zhou; Chunqin, Zheng; Yingming, Qiang; Holmér, Ingvar; Gao, Chuansi; Kuklane, Kalev

    2010-01-01

    There are about a hundred manikin users around the world. Some of them use the manikin such as 'Walter' and 'Tore' to evaluate the comfort of clothing ensembles according to their thermal insulation and moisture resistance. A 'Walter' manikin is made of water and waterproof breathable fabric 'skin', which simulates the characteristics of human perspiration. So evaporation, condensation or sorption and desorption are always accompanied by heat transfer. A 'Tore' manikin only has dry heat exchange by conduction, radiation and convection from the manikin through clothing ensembles to environments. It is an ideal apparatus to measure the thermal insulation of the clothing ensemble and allows evaluation of thermal comfort. This paper compares thermal insulation measured with dry 'Tore' and sweating 'Walter' manikins. Clothing ensembles consisted of permeable and impermeable clothes. The results showed that the clothes covering the 'Walter' manikin absorbed the moisture evaporated from the manikin. When the moisture transferred through the permeable clothing ensembles, heat of condensation could be neglected. But it was observed that heavy condensation occurred if impermeable clothes were tested on the 'Walter' manikin. This resulted in a thermal insulation difference of clothing ensembles on the dry and perspiration manikins. The thermal insulation obtained from the 'Walter' manikin has to be modified when heavy condensation occurs. The modified equation is obtained in this study

  6. Exploring the influence of culture conditions on kefir's anticancer properties.

    Science.gov (United States)

    Hatmal, Ma'mon M; Nuirat, Abeer; Zihlif, Malek A; Taha, Mutasem O

    2018-05-01

    Cancer is a major health problem in many parts of the world. Conventional anticancer treatments are painful, expensive, and unsafe. Therefore, demand is increasing for cancer treatments preferentially in the form of functional foods or nutritional supplements. Kefir, a traditional fermented milk dairy product, has significant antimutagenic and antitumor properties. This research addresses the hypothesis that kefir's anticancer properties are affected by fermentation conditions. Initially, kefir extracts prepared under standard conditions were screened against 7 cancer cell lines using the tetrazolium dye 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide colorimetric assay. Colon cancer and chronic myelogenous leukemia cells were found to be most susceptible to kefir extracts. Subsequently, a factorial design was implemented to assess the effects of 3 fermentation times (24, 48, and 72 h), 3 kefir-to-milk ratios (2, 5, and 10% wt/vol), and 3 fermentation temperatures (4, 25, and 40°C) on kefir's anticancer properties. Remarkably, exploration of the fermentation conditions allowed the anticancer properties of kefir to be enhanced by 5- to 8-fold against susceptible cell lines. Overall, these results demonstrate the possibility of optimizing the anticancer properties of kefir as a functional food in cancer therapy. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  7. Modeling of Kefir Production with Fuzzy Logic

    Directory of Open Access Journals (Sweden)

    Hüseyin Nail Akgül

    2014-06-01

    Full Text Available The fermentation is ended with pH 4.6 values in industrial production of kefir. In this study, the incubation temperature, the incubation time and inoculums of culture were chose as variable parameters of kefir. In conventional control systems, the value of pH can be found by trial method. In these systems, if the number of input parameters is greater, the method of trial and error creates a system dependent on the person as well as troublesome. Fuzzy logic can be used in such cases. Modeling studies with this fuzzy logic control are examined in two portions. The first part consists of fuzzy rules and membership functions, while the second part consists of clarify. Kefir incubation temperature between 20 and 25°C, the incubation period between 18 to 22 hours and the inoculum ratio of culture between 1-5% are selected for optimum production conditions. Three separate fuzzy sets (triangular membership function are used to blur the incubation temperature, the incubation time and the inoculum ratio of culture. Because the membership function numbers belonging to the the input parameters are 3 units, 3x3x3=27 line rule is obtained by multiplying these numbers. The table of fuzzy rules was obtained using the method of Mamdani. The membership function values were determined by the method of average weight using three trapezoidal area of membership functions created for clarification. The success of the system will be found, comparing the numerical values obtained with pH values that should be. Eventually, to achieve the desired pH value of 4.6 in the production of kefir, with the using of fuzzy logic, the workload of people will be decreased and the productivity of business can be increased. In this case, it can be provided savings in both cost and time.

  8. "Petit suisse" cheese from kefir: an alternative dessert with microorganisms of probiotic activity Queijo "Petit suisse" de kefir: uma alternativa de sobremesa com microorganismos de ação probiótica

    Directory of Open Access Journals (Sweden)

    Thanise Sabrina Souza Santos

    2012-09-01

    Full Text Available "Petit Suisse" is a creamy cheese. Kefir is a symbiotic mixture of lactic acid bacteria and yeasts with probiotic activity including immunomodulation and balance of intestinal microflora. The present study aims to develop "Petit Suisse" cheese from kefir. Kefir grains were grown in pasteurized cow milk, and after the separation of kefir the serum was discarded and the "Petit Suisse" cheese was prepared using strawberry, mangaba, herbs, and dried tomatoes. The acceptance of the different preparations was evaluated using a nine-point hedonic scale followed by ANOVA. The sweet and salty products were compared by the Student's t-test. Purchase intent was evaluated by the means test and frequency distribution. All products were well accepted by the judges. The product was characterized by low yield, but it can be prepared at home at low cost. The nutritional composition analyses and the variety of flavors as well as the range of age of the judges are alternatives for further studies.Petit suisse é um queijo de consistência pastosa. O kefir é um produto resultante da simbiose entre bactérias ácido-láticas e leveduras, e apresenta ação probiótica, como imunomodulação e balanço da microbiota intestinal. O presente estudo buscou desenvolver petit suisse de kefir. Os grãos foram cultivados no leite de vaca pasteurizado e, após separação do kefir, seguiu-se para dessoragem e preparo do petit suisse nos sabores morango, mangaba, ervas e tomate seco. Com escala hedônica estruturada de nove pontos, avaliou-se aceitação pela ANOVA. As amostras doces e salgadas foram comparadas por meio do teste t de Student e a intenção de compra foi avaliada por meio do teste de médias e de distribuição das frequências. As amostras apresentaram boa aceitação pelos julgadores. O produto pronto apresentou baixo rendimento, mas pode ser reproduzido em nível domiciliar com baixo custo. A análise da composição nutricional e a variação dos sabores e

  9. Cheese production using kefir culture entrapped in milk proteins.

    Science.gov (United States)

    Dimitrellou, Dimitra; Kandylis, Panagiotis; Kourkoutas, Yiannis; Koutinas, Athanasios A; Kanellaki, Maria

    2015-05-01

    The aim of the present study was to evaluate the use of kefir culture entrapped in casein and in whey protein as starter cultures for the production of Feta-type cheese. Microbiological analysis showed that counts of enterobacteria, coliforms, and staphylococci were significantly reduced due to kefir culture. In addition, the effect of kefir culture on the formation of volatile compounds, such as esters, organic acids, alcohols, carbonyl compounds, and lactones, was also investigated using the SPME GC/MS technique. Cheese samples produced with kefir culture entrapped in milk proteins presented improved profile of aroma-related compounds. Principal component analysis of the results indicated that the volatile composition of the different cheese types was dependent on the nature of the starter culture. Finally, the sensory evaluation showed that the products produced with kefir culture had a soft, fine taste, and were of improved quality.

  10. Manufacture and characterization of kefir made from cow and buffalo milk, using kefir grain and starter culture.

    Science.gov (United States)

    Gul, O; Mortas, M; Atalar, I; Dervisoglu, M; Kahyaoglu, T

    2015-03-01

    The microbiological and chemical characteristics as well as organic and amino acid profiles of kefir samples made from cow and buffalo milks fermented by kefir grains and starter culture were investigated during storage for 21 d at 4°C. After incubation, lactic, acetic, and citric acid concentrations showed a difference among the samples due to milk type and production methods. Storage time had little effect on the organic acid values of kefir samples. As compared with cow milk kefir, buffalo milk kefir had higher numbers of microorganisms, except lactobacilli, at the end of storage. Whereas pH and titratable acidity exhibited similar changes during storage in all kefir samples, ethanol levels were significantly increased in buffalo milk kefir samples. Glutamic acid was the major amino acid at all sampling times for all samples. Tyrosine, serine, histidine, alanine, methionine, and lysine concentrations were determined to be different in all samples depending on milk type. In general, due to the higher microbial population (especially yeast), kefir made from buffalo milk may be preferred. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  11. Investigation of the instability and low water kefir grain growth during an industrial water kefir fermentation process.

    Science.gov (United States)

    Laureys, David; Van Jean, Amandine; Dumont, Jean; De Vuyst, Luc

    2017-04-01

    A poorly performing industrial water kefir production process consisting of a first fermentation process, a rest period at low temperature, and a second fermentation process was characterized to elucidate the causes of its low water kefir grain growth and instability. The frozen-stored water kefir grain inoculum was thawed and reactivated during three consecutive prefermentations before the water kefir production process was started. Freezing and thawing damaged the water kefir grains irreversibly, as their structure did not restore during the prefermentations nor the production process. The viable counts of the lactic acid bacteria and yeasts on the water kefir grains and in the liquors were as expected, whereas those of the acetic acid bacteria were high, due to the aerobic fermentation conditions. Nevertheless, the fermentations progressed slowly, which was caused by excessive substrate concentrations resulting in a high osmotic stress. Lactobacillus nagelii, Lactobacillus paracasei, Lactobacillus hilgardii, Leuconostoc mesenteroides, Bifidobacterium aquikefiri, Gluconobacter roseus/oxydans, Gluconobacter cerinus, Saccharomyces cerevisiae, and Zygotorulaspora florentina were the most prevalent microorganisms. Lb. hilgardii, the microorganism thought to be responsible for water kefir grain growth, was not found culture-dependently, which could explain the low water kefir grain growth of this industrial process.

  12. Comparative study of the biochemical changes and volatile compound formations during the production of novel whey-based kefir beverages and traditional milk kefir

    OpenAIRE

    Magalhães, Karina Teixeira; Dragone, Giuliano; Pereira, Gilberto V. de Melo; Oliveira, J. M.; Domingues, Lucília; Teixeira, J. A.; Silva, João B. Almeida e; Schwan, Rosane F.

    2011-01-01

    Cheese whey (CW) and deproteinised cheese whey (DCW) were investigated for their suitability as novel substrates for the production of kefir-like beverages. Lactose consumption, ethanol production, as well as organic acids and volatile compounds formation, were determined during CW and DCW fermentation by kefir grains and compared with values obtained during the production of traditional milk kefir. The results showed that kefir grains were able to utilise lactose from CW and DCW and produce ...

  13. Mathematical model for solar drying of potato cylinders with thermal conductivity radially modulated

    Science.gov (United States)

    Trujillo Arredondo, Mariana

    2014-05-01

    A mathematical model for drying potato cylinders using solar radiation is proposed and solved analytically. The model incorporates the energy balance for the heat capacity of the potato, the radiation heat transfer from the potato toward the drying chamber and the solar radiation absorbed by the potato during the drying process. Potato cylinders are assumed to exhibit a thermal conductivity which is radially modulated. The method of the Laplace transform, with integral Bromwich and residue theorem will be applied and the analytic solutions for the temperature profiles in the potato cylinder will be derived in the form of an infinite series of Bessel functions, when the thermal conductivity is constant; and in the form of an infinite series of Heun functions, when the thermal conductivity has a linear radial modulation. All computations are performed using computer algebra, specifically Maple. It is expected that the analytical results obtained will be useful in food engineering and industry. Our results suggest some lines for future investigations such as the adoption of more general forms of radial modulation for the thermal conductivity of potato cylinders; and possible applications of other computer algebra software such as Maxima and Mathematica.

  14. Comparison of Thermal Stability of Dry High-strength Concrete and Wet High-strength Concrete

    Directory of Open Access Journals (Sweden)

    Musorina Tatiana

    2018-01-01

    Full Text Available High-strength concrete is a modern material, which occupies it`s own niche on the construction material market. It is applicable in a large-scale high-rise construction, particularly an underground construction is a frequently used solution for a space saving. Usually underground structure is related to a wet usage environment. Though not all properties of the high-strength concrete are investigated to the full extent. Under adverse climatic conditions of the Russian Federation one of the most important properties for constructional materials is a thermal capacity. Therefore, the main purpose of the paper is to compare a thermal capacity of the high-strength concrete in humid conditions and a thermal capacity of the high-strength concrete in dry operational condition. During the study dependency between thermal capacity and design wall thickness and ambient humidity has to be proven with two experiments. As a result the theoretical relation between thermal capacity characteristic – thermal inertia and wall thickness and ambient humidity was confirmed by the experimental data. The thermal capacity of a building is in direct ratio to the construction thickness. It follows from the experiments and calculations that wet high-strength concrete has less thermal stability.

  15. Comparison of Thermal Stability of Dry High-strength Concrete and Wet High-strength Concrete

    Science.gov (United States)

    Musorina, Tatiana; Katcay, Aleksandr; Selezneva, Anna; Kamskov, Victor

    2018-03-01

    High-strength concrete is a modern material, which occupies it`s own niche on the construction material market. It is applicable in a large-scale high-rise construction, particularly an underground construction is a frequently used solution for a space saving. Usually underground structure is related to a wet usage environment. Though not all properties of the high-strength concrete are investigated to the full extent. Under adverse climatic conditions of the Russian Federation one of the most important properties for constructional materials is a thermal capacity. Therefore, the main purpose of the paper is to compare a thermal capacity of the high-strength concrete in humid conditions and a thermal capacity of the high-strength concrete in dry operational condition. During the study dependency between thermal capacity and design wall thickness and ambient humidity has to be proven with two experiments. As a result the theoretical relation between thermal capacity characteristic - thermal inertia and wall thickness and ambient humidity was confirmed by the experimental data. The thermal capacity of a building is in direct ratio to the construction thickness. It follows from the experiments and calculations that wet high-strength concrete has less thermal stability.

  16. Nitrogen behaviour during thermal drying of mechanically dewatered biosludge from pulp and paper industry.

    Science.gov (United States)

    Mustonen, Kati; Deviatkin, Ivan; Havukainen, Jouni; Horttanainen, Mika

    2018-04-01

    An ongoing call to implement a circular economy is underway in the European Union, and a specific attention has been placed on the forest industry, which seeks additional recycling routes for its side streams, including biosludge. Biosludge is often dried and incinerated, thus wasting the nitrogen contained therein. This paper describes a study in which the release of nitrogen during thermal drying, the impact of the drying temperatures of 130°C, 180°C, and 210°C on the mass of ammonia released, and the potential for recovery of nitrogen from biosludge were examined. The results indicate that 1310-1730 mg kgTS -1 of nitrogen was released, which corresponded to 56-74% of the soluble nitrogen in biosolids or 4.0-5.3% of the total nitrogen. Of this released nitrogen, 83-85% was identified in condensate and absorbing water, thus indicating a high potential for recovering nitrogen from biosludge.

  17. Basic Considerations for Dry Storage of Spent Nuclear Fuels and Revisited CFD Thermal Analysis on the Concrete Cask

    Energy Technology Data Exchange (ETDEWEB)

    Noh, Jae Soo [ACT Co. Ltd., Daejeon (Korea, Republic of); Park, Younwon; Song, Sub Lee [BEES Inc., Daejeon (Korea, Republic of); Kim, Hyeun Min [KAIST, Daejeon (Korea, Republic of)

    2016-10-15

    The integrity of storage facility and also of the spent nuclear fuel itself is considered very important. Storage casks can be located in a designated area on a site or in a designated storage building. A number of different designs for dry storage have been developed and used in different countries. Dry storage system was classified into two categories by IAEA. One is container including cask and silo, the other one is vault. However, there is various way of categorization for dry storage system. Dry silo and cask are usually classified separately, so the dry storage system can be classified into three different types. Furthermore, dry cask storage can be categorized into two types based on the type of the materials, concrete cask and metal cask. In this paper, the design characteristics of dry storage cask are introduced and computational fluid dynamics (CFD) based thermal analysis for concrete cask is revisited. Basic principles for dry storage cask design were described. Based on that, thermal analysis of concrete dry cask was introduced from the study of H. M. Kim et al. From the CFD calculation, the temperature of concrete wall was maintained under the safety criteria. From this fundamental analysis, further investigations are expected. For example, thermal analysis on the metal cask, thermal analysis on horizontally laid spent nuclear fuel assemblies for transportation concerns, and investigations on better performance of natural air circulation in dry cask can be promising candidates.

  18. Analysis of Proximate and Protein Profile of Kefir from Fermented Goat and Cow Milk

    Directory of Open Access Journals (Sweden)

    Erwin Hidayat

    2015-09-01

    Full Text Available This research aims to analyze the characteristics of proximate and protein profile in kefir from fermented goat milk and cow milk with different concentration of kefir grains. The research design was true experimental with Completely Randomized Design (CRD of 3 repetitions. The research procedures consisted of kefir production, proximate analysis and protein profile characterization. Proximate assay result was analyzed by using LSD, whereas the protein profile was analyzed by descriptive qualitative method. Based on the analysis of kefir proximate levels, the kefir grain (5% showed the highest proximate level of both kefirs from goat milk and cow milk. The analysis of protein profile of cow milk kefir showed 75 kDa of protein ribbon, while the goat milk kefir showed 48 kDa, 60 kDa and 75 kDa. Therefore it can be concluded that the proximate level of goat and cow milk kefir with different concentration of kefir grains showed significant differences in the nutrition content as well as its protein profiles.Tujuan dari penelitian ini adalah menganalisis karakteristik proksimat dan profil protein pada kefir hasil fermentasi susu kambing dan susu sapi dengan konsentrasi biji kefir yang berbeda-beda. Penelitian ini adalah eksperimen murni, dengan Rancangan Acak Lengkap (RAL 3 kali ulangan. Prosedur penelitian meliputi pembuatan kefir, analisis proksimat dan profil protein. Data hasil proksimat dianalisi uji BNT, sedangkan profil protein dianalisis deskriptif kualitatif. Berdasarkan analisis kadar proksimat kefir, kefir grains 5% menunjukan kadar proksimat paling tinggi baik pada kefir susu kambing dan susu sapi. Sedangkan analisis profil protein kefir susu sapi menunjukan pita protein 75 kDa, pada kefir susu kambing yaitu 48 kDa, 60 kDa dan 75 kDa. Simpulan dari penelitian ini bahwa kadar proksimat kefir susu kambing dan susu sapi dengan konsentrasi kefir grains yang berbeda menunjukan perbedaan kandungan yang berbeda secara signifikan dengan

  19. THERMAL POWER LOSS COMPENSATION IN THE PRODUCTION OF COOKED AND DRIED GRAINS WITH HEAT PUMPS USING

    Directory of Open Access Journals (Sweden)

    S. A. Shevtsov

    2015-01-01

    Full Text Available Using scientificand practical experience and analysis of recent innovative activity on modernization of food concentrates production, a new variant of the energy-efficient processing of cereal crops using superheated steam and direct involvement in the cooking and drying process waste energy using the vapor compression heat pump was suggested. A method for production of cereal concentrates, which is realized using microprocessor control of technological parameters. According to the information on the processes of cereals washing, cooking, drying and cooling microprocessor provides regime parameters control under the restrictions due to both yield of cooked and dried cereal of high quality and economic feasibility. At the same time the amount of moisture is continuously determined in the recirculation loop formed by the evaporation from the cereals in the drying process. To implement the proposed method of cooked and dried cereals production it is offered to use refrigerationand compressor unit operating in a heat pump mode. The refrigerant to be used is khladon 12V1 CF2ClBr with a boiling point in the evaporator of 4°C and the condensing temperature of 153.7 °C. The use of the heat pump in the heat supply system of cooked and dried cereals production instead of electric heaters will reduce power costs by 1.72 times. The proposed method for the production and control of technological parameters in the field of the product acceptable technological properties will provide high quality cooked and dried cereals; an increase in thermal efficiency by making full use of the waste heat of superheated steam; the reduction of specific energy consumption by 25-30 %; the creation of waste-free and environmentally friendly technologies for cereal production.

  20. A simplified computational scheme for thermal analysis of LWR spent fuel dry storage and transportation casks

    International Nuclear Information System (INIS)

    Kim, Chang Hyun

    1997-02-01

    A simplified computational scheme for thermal analysis of the LWR spent fuel dry storage and transportation casks has been developed using two-step thermal analysis method incorporating effective thermal conductivity model for the homogenized spent fuel assembly. Although a lot of computer codes and analytical models have been developed for application to the fields of thermal analysis of dry storage and/or transportation casks, some difficulties in its analysis arise from the complexity of the geometry including the rod bundles of spent fuel and the heat transfer phenomena in the cavity of cask. Particularly, if the disk-type structures such as fuel baskets and aluminium heat transfer fins are included, the thermal analysis problems in the cavity are very complex. To overcome these difficulties, cylindrical coordinate system is adopted to calculate the temperature profile of a cylindrical cask body using the multiple cylinder model as the step-1 analysis of the present study. In the step-2 analysis, Cartesian coordinate system is adopted to calculate the temperature distributions of the disk-type structures such as fuel basket and aluminium heat transfer fin using three- dimensional conduction analysis model. The effective thermal conductivity for homogenized spent fuel assembly based on Manteufel and Todreas model is incorporated in step-2 analysis to predict the maximum fuel temperature. The presented two-step computational scheme has been performed using an existing HEATING 7.2 code and the effective thermal conductivity for the homogenized spent fuel assembly has been calculated by additional numerical analyses. Sample analyses of five cases are performed for NAC-STC including normal transportation condition to examine the applicability of the presented simplified computational scheme for thermal analysis of the large LWR spent fuel dry storage and transportation casks and heat transfer characteristics in the cavity of the cask with the disk-type structures

  1. MILK KEFIR: COMPOSITION, MICROBIAL CULTURES, BIOLOGICAL ACTIVITIES AND RELATED PRODUCTS

    Directory of Open Access Journals (Sweden)

    Maria Rosa Prado

    2015-10-01

    Full Text Available In recent years, there has been a strong focus on beneficial foods with probiotic microorganisms and functional organic substances. In this context, there is an increasing interest in the commercial use of kefir, since it can be marketed as a natural beverage that has health promoting bacteria. There are numerous commercially available kefir based-products. Kefir may act as a matrix in the effective delivery of probiotic microorganisms in different types of products. Also, the presence of kefir’s exopolysaccharides, known as kefiran, which has biological activity, certainly adds value to products. Kefiran can also be used separately in other food products and as a coating film for various food and pharmaceutical products. This article aims to update the information about kefir and its microbiological composition, biological activity of the kefir’s microflora and the importance of kefiran as a beneficial health substance.

  2. The effect of kefir starter on Thai fermented sausage product

    Directory of Open Access Journals (Sweden)

    Marisa Jatupornpipat

    2007-07-01

    Full Text Available The effect of kefir starter from Wilderness Family Naturals Company on the initial formulation of Thai fermented sausage were evaluated. The differences found among batches in the main microbial populations and pH were not significant. Only, the total acid of batch D (added the kefir starter 15 ml was significantly higher (P0.05. It is concluded that the addition of kefir starter (7 ml could be useful to improve the final quality of Thai fermented sausages. The addition of kefir starter that initiates rapid acidification of the raw meat and that leads to a desirable sensory quality of the end-product are used for the production of fermented sausages, and represents a way of improving and optimizing the sausage fermentation process and achieving tastier, safer, and healthier products.

  3. Gastroprotective effect of kefir on ulcer induced in irradiated rats.

    Science.gov (United States)

    Fahmy, Hanan A; Ismail, Amel F M

    2015-03-01

    The current study was designed to investigate the protective effect of kefir milk on ethanol-induced gastric ulcers in γ-irradiated rats. The results of the present study revealed that treatment with γ-irradiation and/or ethanol showed a significant increase in ulcers number, total acidity, peptic, H(+)K(+)ATPase, MMP-2 and MMP-9 activities and MDA level, which were accompanied by a significant decrease in the mucus content, the stomach GSH level, the GSH-Px activity and DNA damage. Pre-treatment with kefir milk exert significant improvement in all the tested parameters. Kefir milk exerts comparable effect to that of the antiulcer drug ranitidine. In conclusion, the present study revealed that oral administration of kefir milk prevents ethanol-induced gastric ulcer in γ-irradiated rats that could attribute to its antioxidant, anti-apoptotic and radio-protective activities. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Kefir protective effects against nicotine cessation-induced anxiety and cognition impairments in rats

    Directory of Open Access Journals (Sweden)

    Negin Noori

    2014-01-01

    Conclusion: This study revealed that Kefir had a potential effect on the treatment of nicotine cessation-induced depression, anxiety and cognition impairment in the animal model. Kefir may be useful for adjunct therapy for nicotine abandonment treatment protocols.

  5. Effects of different fermentation parameters on quality characteristics of kefir.

    Science.gov (United States)

    Kök-Taş, Tuğba; Seydim, Atif C; Ozer, Barbaros; Guzel-Seydim, Zeynep B

    2013-02-01

    The main objective of the study was to determine the effects of different fermentation parameters on kefir quality. Kefir samples were produced using kefir grains or natural kefir starter culture, and fermentation was carried out under normal or modified atmosphere (10% CO(2)) conditions. The microbiological (lactobacilli, lactococci, Lactobacillus acidophilus, Bifidobacterium spp., and yeasts), chemical (pH, lactic acid, total solids, protein, ethanol, exopolysaccharide contents), rheological, and sensory properties of kefir samples were investigated during a 21-d storage period. The use of different fermentation parameters or the choice of grain versus natural kefir starter culture did not significantly affect the content of microorganisms. Lactobacilli, lactococci, and yeast contents of kefir samples varied between 9.21 and 9.28, 9.23 and 9.29, and 4.71 and 5.53 log cfu/mL, respectively, on d 1 of storage. Contents of L. acidophilus and Bifidobacterium spp. were between 5.78 and 6.43 and between 3.19 and 6.14 log cfu/mL, respectively, during 21 d of storage. During the storage period, pH, lactic acid (%), total solids (%), protein (%), acetaldehyde, and ethanol contents of kefir samples ranged from 4.29 to 4.53, from 0.81 to 0.95%, from 7.81 to 8.21%, from 3.09 to 3.48%, from 3.8 to 23.6 mg/L, and from 76.5 to 5,147 mg/L, respectively. The exopolysaccharide contents of the samples decreased during 21 d of cold storage; the samples fermented under modified atmosphere had relatively higher exopolysaccharide contents, indicating higher potential therapeutic properties. The kefir samples exhibited non-Newtonian pseudoplastic flow behavior according to the power law model. According to the sensory results, kefir produced from natural kefir starter culture under CO(2) atmosphere had the highest overall evaluation score at d 1. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  6. Optimization of a fermented soy product formulation with a kefir culture and fiber using a simplex-centroid mixture design.

    Science.gov (United States)

    Baú, Tahis Regina; Garcia, Sandra; Ida, Elza Iouko

    2013-12-01

    The objective of this work was to optimize a fermented soy product formulation with kefir and soy, oat and wheat fibers and to evaluate the fiber and product characteristics. A simplex-centroid mixture design was used for the optimization. Soymilk, soy, oat and wheat fiber mixtures, sucrose and anti-foaming agent were used for the formulation, followed by thermal treatment, cooling and the addition of flavoring. Fermentation was performed at 25 °C with a kefir culture until a pH of 4.5 was obtained. The products were cooled, homogenized and stored for analysis. From the mathematical models and variables response surface and desirability an optimal fermented product was formulated containing 3% (w/w) soy fiber. Compared with the other formulations, soy fermented product with 3% soy fiber had the best acidity, viscosity, syneresis, firmness and Lactococcus lactis count.

  7. Comparison of antioxidant capacity of cow and ewe milk kefirs.

    Science.gov (United States)

    Yilmaz-Ersan, Lutfiye; Ozcan, Tulay; Akpinar-Bayizit, Arzu; Sahin, Saliha

    2018-02-21

    This research aimed to evaluate the effects of using either grain or commercial starter culture on the antioxidative capacity of cow and ewe milk kefirs. The antioxidant capacity of kefir samples during fermentation and 21 d of storage was assessed by using 3 assays: 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical cation decolorization; 2,2-diphenyl-1-picrylhydrazyl (DPPH • ) radical scavenging activity assay; and Fe +3 -reducing power (ferric reducing antioxidant power assay, FRAP). Vitamin E and β-carotene contents were also quantified. All kefir samples exhibited varying values for DPPH, ABTS, and FRAP assays depending on the starter culture and milk type. Vitamin E and β-carotene contents were similar in all kefir samples during storage. The results of this study suggest that milk type (cow or ewe) and culture type (kefir grains or commercial starter) were the significant parameters for the antioxidative activity of kefir. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  8. Effects of kefir on ischemia-reperfusion injury.

    Science.gov (United States)

    Yener, A U; Sehitoglu, M H; Ozkan, M T A; Bekler, A; Ekin, A; Cokkalender, O; Deniz, M; Sacar, M; Karaca, T; Ozcan, S; Kurt, T

    2015-01-01

    We aimed to investigate the effect of kefir on Ischemia-Reperfusion (I/R) injury on rats. 24 male Sprague-Dawley rats between 250-350 g were selected. Rats were divided into three groups, and there were eight rats in each group. Rats were fed for 60 days. All of the rats were fed with the same diet for the first 30 days. In the second thirty days, kefir [10 cc/kg/day body weight (2 x 109 cfu/kg/day)] was added to the diet of the study group by gavage method. In all groups, lung and kidney tissues were removed after the procedure and rats were sacrificed. The biochemical and histopathological changes were observed in the lung and kidney within the samples. Serum urea, creatinine and tumor necrosis factor (TNF-α) were determined. Kefir + I/R groups was compared with I/R groups, a significant decrease (p Kefir + I/R groups of renal tissues were significantly (p Kefir reduced the levels of serum urea, creatinine and TNF-α significantly.   This would be useful in this model against ischemia/reperfusion, and shows the protective effect of kefir in tissue and serum functions.

  9. Cna 1 spent fuel element interim dry storage system thermal analysis

    International Nuclear Information System (INIS)

    Hilal, R. E; Garcia, J. C; Delmastro, D. F

    2006-01-01

    At the moment, the Atucha I Nuclear Power Plant (Cnea-I) located in the city of Lima, has enough room to store its spent fuel (Sf) in their two pools spent fuel until about 2015.In case of life extension a spend fuel element interim dry storage system is needed.Nucleolectrica Argentina S.A. (N A-S A) and the Comision Nacional de Energia Atomica (Cnea), have proposed different interim dry storage systems.These systems have to be evaluated in order to choose one of them.The present work's objective is the thermal analysis of one dry storage alternative for the Sf element of Cna 1.In this work a simple model was developed and used to perform the thermal calculations corresponding to the system proposed by Cnea.This system considers the store of sealed containers with 37 spent fuels in concrete modules.Each one of the containers is filled in the pool houses and transported to the module in a transference cask with lead walls.Fulfill the maximum cladding temperature requirement ( [es

  10. Effects of kefir as a probiotic source on the performance of goat kids ...

    African Journals Online (AJOL)

    The aim of this study was to investigate the effect of kefir as a probiotic on the performance of goat kids during the pre- (45 days) and post-weaning (45 days) periods. Forty eight kids were randomly allocated to four treatment groups: Control, Kefir, Auto-Kefir (autoclaved) and Probiotic (a commercial probiotic). The kids were ...

  11. Thermal-Hydraulic Results for the Boiling Water Reactor Dry Cask Simulator.

    Energy Technology Data Exchange (ETDEWEB)

    Durbin, Samuel [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lindgren, Eric R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-09-01

    The thermal performance of commercial nuclear spent fuel dry storage casks is evaluated through detailed numerical analysis. These modeling efforts are completed by the vendor to demonstrate performance and regulatory compliance. The calculations are then independently verified by the Nuclear Regulatory Commission (NRC). Carefully measured data sets generated from testing of full sized casks or smaller cask analogs are widely recognized as vital for validating these models. Recent advances in dry storage cask designs have significantly increased the maximum thermal load allowed in a cask in part by increasing the efficiency of internal conduction pathways and by increasing the internal convection through greater canister helium pressure. These same canistered cask systems rely on ventilation between the canister and the overpack to convect heat away from the canister to the environment for both aboveground and belowground configurations. While several testing programs have been previously conducted, these earlier validation attempts did not capture the effects of elevated helium pressures or accurately portray the external convection of aboveground and belowground canistered dry cask systems. The purpose of this investigation was to produce validation-quality data that can be used to test the validity of the modeling presently used to determine cladding temperatures in modern vertical dry casks. These cladding temperatures are critical to evaluate cladding integrity throughout the storage cycle. To produce these data sets under well-controlled boundary conditions, the dry cask simulator (DCS) was built to study the thermal-hydraulic response of fuel under a variety of heat loads, internal vessel pressures, and external configurations. An existing electrically heated but otherwise prototypic BWR Incoloy-clad test assembly was deployed inside of a representative storage basket and cylindrical pressure vessel that represents a vertical canister system. The symmetric

  12. Thermal analysis of dry concrete canister storage system for CANDU spent fuel

    International Nuclear Information System (INIS)

    Ryu, Yong Ho

    1992-02-01

    This paper presents the results of a thermal analysis of the concrete canisters for interim dry storage of spent, irradiated Canadian Deuterium Uranium(CANDU) fuel. The canisters are designed to contain 6-year-old fuel safely for periods of 50 years in stainless steel baskets sealed inside a steel-lined concrete shield. In order to assure fuel integrity during the storage, fuel rod temperature shall not exceed the temperature limit. The contents of thermal analysis include the following : 1) Steady state temperature distributions under the conservative ambient temperature and insolation load. 2) Transient temperature distributions under the changes in ambient temperature and insolation load. Accounting for the coupled heat transfer modes of conduction, convection, and radiation, the computer code HEATING5 was used to predict the thermal response of the canister storage system. As HEATING5 does not have the modeling capability to compute radiation heat transfer on a rod-to-rod basis, a separate calculating routine was developed and applied to predict temperature distribution in a fuel bundle. Thermal behavior of the canister is characterized by the large thermal mass of the concrete and radiative heat transfer within the basket. The calculated results for the worst case (steady state with maximum ambient temperature and design insolation load) indicated that the maximum temperature of the 6 year cooled fuel reached to 182.4 .deg. C, slightly above the temperature limit of 180 .deg. C. However,the thermal inertia of the thick concrete wall moderates the internal changes and prevents a rise in fuel temperature in response to ambient changes. The maximum extent of the transient zone was less than 75% of the concrete wall thickness for cyclic insolation changes. When transient nature of ambient temperature and insolation load are considered, the fuel temperature will be a function of the long term ambient temperature as opposed to daily extremes. The worst design

  13. Using Simplified Thermal Inertia to Determine the Theoretical Dry Line in Feature Space for Evapotranspiration Retrieval

    Directory of Open Access Journals (Sweden)

    Sujuan Mi

    2015-08-01

    Full Text Available With the development of quantitative remote sensing, regional evapotranspiration (ET modeling based on the feature space has made substantial progress. Among those feature space based evapotranspiration models, accurate determination of the dry/wet lines remains a challenging task. This paper reports the development of a new model, named DDTI (Determination of Dry line by Thermal Inertia, which determines the theoretical dry line based on the relationship between the thermal inertia and the soil moisture. The Simplified Thermal Inertia value estimated in the North China Plain is consistent with the value measured in the laboratory. Three evaluation methods, which are based on the comparison of the locations of the theoretical dry line determined by two models (DDTI model and the heat energy balance model, the comparison of ET results, and the comparison of the evaporative fraction between the estimates from the two models and the in situ measurements, were used to assess the performance of the new model DDTI. The location of the theoretical dry line determined by DDTI is more reasonable than that determined by the heat energy balance model. ET estimated from DDTI has an RMSE (Root Mean Square Error of 56.77 W/m2 and a bias of 27.17 W/m2; while the heat energy balance model estimated ET with an RMSE of 83.36 W/m2 and a bias of −38.42 W/m2. When comparing the coeffcient of determination for the two models with the observations from Yucheng, DDTI demonstrated ET with an R2 of 0.9065; while the heat energy balance model has an R2 of 0.7729. When compared with the in situ measurements of evaporative fraction (EF at Yucheng Experimental Station, the ET model based on DDTI reproduces the pixel scale EF with an RMSE of 0.149, much lower than that based on the heat energy balance model which has an RMSE of 0.220. Also, the EF bias between the DDTI model and the in situ measurements is 0.064, lower than the EF bias of the heat energy balance model

  14. Synthesis of platinum nanoparticles using dried Anacardium occidentale leaf and its catalytic and thermal applications.

    Science.gov (United States)

    Sheny, D S; Philip, Daizy; Mathew, Joseph

    2013-10-01

    An environment friendly approach for the synthesis of Pt nanoparticles (NPs) using dried leaf powder of Anacardium occidentale is reported. The formation of Pt NPs is monitored using UV-Vis spectrophotometer. FTIR spectra reveal that proteins are bound to Pt nanoparticles. TEM images show irregular rod shaped particles which are crystalline. The quantity of leaf powder plays a vital role in determining the size of particles. Synthesized NPs exhibit good catalytic activity in the reduction of aromatic nitrocompound. The effective thermal conductivity of synthesized Pt/water nanofluid has been measured and found to be enhanced to a good extent. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Antifungal effect of kefir fermented milk and shelf life improvement of corn arepas.

    Science.gov (United States)

    Gamba, Raúl Ricardo; Caro, Carlos Andrés; Martínez, Olga Lucía; Moretti, Ana Florencia; Giannuzzi, Leda; De Antoni, Graciela Liliana; León Peláez, Angela

    2016-10-17

    Fungal contamination negatively affects the production of cereal foods such as arepa loaf, an ancient corn bread consumed daily in several countries of Latin-America. Chemical preservatives such as potassium sorbate are applied in order to improve the arepa's shelf life and to reduce the health risks. The use of natural preservatives such as natural fermented products in food commodities is a common demand among the consumers. Kefir is a milk fermented beverage obtained by fermentation of kefir grains. Its antibacterial and probiotic activity has been exhaustively demonstrated. Our objectives were to determine the antifungal effect of kefir fermented milk on Aspergillus flavus AFUNL5 in vitro and to study if the addition of kefir fermented milk to arepas could produce shelf life improvement. We determined the antifungal effect on solid medium of kefir cell-free supernatants (CFS) obtained under different fermentation conditions. Additionally, we compared the antifungal effect of kefir CFS with that obtained with unfermented milk artificially acidified with lactic plus acetic acids (lactic and acetic acids at the same concentration determined in kefir CFS) or with hydrochloric acid. Finally, kefir was added to the corn products either in the loaf recipe (kefir-baked arepas) or sprayed onto the baked-loaf surface (kefir-sprayed arepas). The loaves' resistance to natural and artificial fungal contamination and their organoleptic profiles were studied. The highest fungal inhibition on solid medium was achieved with kefir CFS produced by kefir grains CIDCA AGK1 at 100 g/L, incubated at 30 °C and fermented until pH 3.3. Other CFS obtained from different fermentation conditions achieved less antifungal activity than that mentioned above. However, CFS of milk fermented with kefir grains, until pH 4.5 caused an increase of growth rates. Additionally, CFS produced by kefir grains CIDCA AGK1 at 100 g/L, incubated at 30 °C and fermented until pH 3.3 achieved higher

  16. Karakteristik Kimiawi dan Mikrobiologi Kefir Susu Sapi dengan Penambahan Susu Kedelai

    OpenAIRE

    Julianto, Budi; Rossi, Evy; ', Yusmarini

    2016-01-01

    The purpose of this research was to observe chemical and microbiology characteristic of three kind of kefir, made from cow milk with addition of soymilk. Observed kefirs were kefir whey (KW), kefir optima (KO), and kefir prima (KP). A Completely Randomized Design (CRD) was used in this research with six treatments and three replications treatment consists of KW1 (100% cow milk), KW2 (50% cow milk: soymilk 50%), KO1 (100% cow milk), KO2 (50% cow milk: 50% soymilk), KP1 (100% cow milk), and KP2...

  17. Peptide profiling of bovine kefir reveals 236 unique peptides released from caseins during its production by starter culture or kefir grains.

    Science.gov (United States)

    Ebner, Jennifer; Aşçı Arslan, Ayşe; Fedorova, Maria; Hoffmann, Ralf; Küçükçetin, Ahmet; Pischetsrieder, Monika

    2015-03-18

    Kefir has a long tradition in human nutrition due to its presupposed health promoting effects. To investigate the potential contribution of bioactive peptides to the physiological effects of kefir, comprehensive analysis of the peptide profile was performed by nano-ESI-LTQ-Orbitrap MS coupled to nano-ultrahigh-performance liquid chromatography. Thus, 257 peptides were identified, mainly released from β-casein, followed by αS1-, κ-, and αS2-casein. Most (236) peptides were uniquely detected in kefir, but not in raw milk indicating that the fermentation step does not only increase the proteolytic activity 1.7- to 2.4-fold compared to unfermented milk, but also alters the composition of the peptide fraction. The influence of the microflora was determined by analyzing kefir produced from traditional kefir grains or commercial starter culture. Kefir from starter culture featured 230 peptide sequences and showed a significantly, 1.4-fold higher proteolytic activity than kefir from kefir grains with 127 peptides. A match of 97 peptides in both varieties indicates the presence of a typical kefir peptide profile that is not influenced by the individual composition of the microflora. Sixteen of the newly identified peptides were previously described as bioactive, including angiotensin-converting enzyme (ACE)-inhibitory, antimicrobial, immunomodulating, opioid, mineral binding, antioxidant, and antithrombotic effects. The present study describes a comprehensive peptide profile of kefir comprising 257 sequences. The peptide list was used to identify 16 bioactive peptides with ACE-inhibitory, antioxidant, antithrombotic, mineral binding, antimicrobial, immunomodulating and opioid activity in kefir. Furthermore, it was shown that a majority of the kefir peptides were not endogenously present in the raw material milk, but were released from milk caseins by proteases of the microbiota and are therefore specific for the product. Consequently, the proteolytic activity and the

  18. Characterization of lactococci isolated from homemade kefir

    Directory of Open Access Journals (Sweden)

    Kojić M.

    2007-01-01

    Full Text Available Five bacteriocin-producing lactococci isolates from traditionally prepared kefir were determined as Lactococcus lactis subsp. lactis. The analyzed isolates showed different plasmid profiles and no cross inhibition between them was detected. Moreover, natural isolate BGKF26 was resistant to the antimicrobial activity of nisin producing strain NP45. Plasmid curing experiments revealed that the genes encoding bacteriocin and proteinase production are located on separate genetic elements, except in BGKF26. Production of the tested bacteriocins depends on the concentration of casitone or triptone in the medium. Higher concentrations of casitone or triptone induce bacteriocin activity. Our DNA-DNA hybridization analyses suggest that the analyzed antimicrobial compounds probably are lactococcin-like bacteriocins.

  19. Computational Fluid Dynamics Thermal Simulations of a Nuclear Fuel Canister During Drying

    Science.gov (United States)

    Trujillo, Corey

    Drying of nuclear fuel canisters is essential to ensure the long-term integrity and safety of nuclear fuel. Vacuum drying, which is one of the drying processes applied to nuclear fuel canisters, consists of lowering the gas pressure in the canister. This introduces a temperature-jump thermal resistance at the gas-solid interface that can cause the cladding temperature to rise beyond the regulated limits. In this thesis, the details of a numerical model of a TN24 PWR nuclear fuel canister filled with Westinghouse 15x15 assemblies is discussed. The model was constructed in ANSYS/Fluent to assess the peak cladding temperatures during vacuum drying and is geometrically-accurate and three-dimensional with distinct regions for the fuel, cladding, backfill, steel basket, and aluminum support. Considerations have been made for conduction in the solid and fluid regions as well as radiation in the fluid regions. A uniform temperature boundary condition of 101.7°C is used at the outside of the canister to conservatively model canister immersed in boiling water. Symmetry boundary conditions were employed such that only one-eighth of the canister was modeled. Steady-state simulations are performed for different fuel heat generation rates and helium pressures, ranging from atmospheric pressure to 100 Pa. Constant thermal accommodation coefficients, which characterize the effect of the temperature-jump thermal resistance at the gas-surface interface are employed. The peak cladding temperature and its radial and axial locations are reported. The maximum allowable heat generation that brings the cladding temperatures to the radial hydride formation limit (TRH = 400°C) is also reported. The results of the three-dimensional model simulations are compared to two-dimensional simulations for the same heat generation rate and pressures. The results show that the rarefaction condition causes the temperature of the rods to significantly increase compared to the continuum condition, which

  20. Evaluation of the subchronic toxicity of kefir by oral administration in Wistar rats.

    Science.gov (United States)

    Diniz Rosa, Damiana; Gouveia Peluzio, Maria do Carmo; Pérez Bueno, Tania; Vega Cañizares, Ernesto; Sánchez Miranda, Lilian; Mancebo Dorbignyi, Betty; Chong Dubí, Dainé; Espinosa Castaño, Ivette; Marcin Grzes Kowiak, Lukasz; Fortes Ferreira, Célia Lucia de Luces

    2014-06-01

    Kefir is obtained by fermentation of milk with complex microbial populations present in kefir grains. Several health-promoting benefits have been attributed to kefir consumption. The objective of this work was to conduct a subchronic toxicity study, offering the rats normal or high-doses of kefir and evaluating growth, hematology and blood chemistry, as well as assessing bacterial translocation and the integrity of the intestinal mucosa of animals. Wistar rats were randomly divided into three groups (n = 6/group): control group received 0.7 mL of water, kefir group received 0.7 mL/day of kefir, (normodose), and Hkefir group received 3.5 mL/day of kefir (fivefold higher dose). Feeding was carried out by gavage. The animals were housed in individual cages and maintained under standard conditions for 4 weeks. The normodose and high-dose of kefir supplementation did not harm the animals since growth, hematology and blood chemistry in rats, as well as the potential pathogenicity in tissues were within normal limits, demonstrating that consumption of normodose and highdose of kefir are safe. In addition, administration of the normodose of kefir reduced cholesterol levels and improved the intestinal mucosa of the rats. These results demonstrate that the consumption of kefir is safe. Importantly, while damages are not seen for the high-dose, the normodose consumption is recommended due to the pronounced beneficial effects, as safety is concerned. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

  1. Microbiological, technological and therapeutic properties of kefir: a natural probiotic beverage

    Directory of Open Access Journals (Sweden)

    Analy Machado de Oliveira Leite

    2013-01-01

    Full Text Available Kefir is a fermented milk beverage produced by the action of bacteria and yeasts that exist in symbiotic association in kefir grains. The artisanal production of the kefir is based on the tradition of the peoples of Caucasus, which has spread to other parts of the world, from the late 19th century, and nowadays integrates its nutritional and therapeutic indications to the everyday food choices of several populations. The large number of microorganisms present in kefir and their microbial interactions, the possible bioactive compounds resulting of microbial metabolism, and the benefits associated with the use this beverage confers kefir the status of a natural probiotic, designated as the 21th century yoghurt. Several studies have shown that kefir and its constituents have antimicrobial, antitumor, anticarcinogenic and immunomodulatory activity and also improve lactose digestion, among others. This review includes data on the technological aspects, the main beneficial effects on human health of kefir and its microbiological composition. Generally, kefir grains contain a relatively stable and specific microbiota enclosed in a matrix of polysaccharides and proteins. Microbial interactions in kefir are complex due to the composition of kefir grains, which seems to differ among different studies, although some predominant Lactobacillus species are always present. Besides, the specific populations of individual grains seem to contribute to the particular sensory characteristics present in fermented beverages. This review also includes new electron microscopy data on the distribution of microorganisms within different Brazilian kefir grains, which showed a relative change in its distribution according to grain origin.

  2. Microbiological, technological and therapeutic properties of kefir: a natural probiotic beverage.

    Science.gov (United States)

    de Oliveira Leite, Analy Machado; Miguel, Marco Antonio Lemos; Peixoto, Raquel Silva; Rosado, Alexandre Soares; Silva, Joab Trajano; Paschoalin, Vania Margaret Flosi

    2013-01-01

    Kefir is a fermented milk beverage produced by the action of bacteria and yeasts that exist in symbiotic association in kefir grains. The artisanal production of the kefir is based on the tradition of the peoples of Caucasus, which has spread to other parts of the world, from the late 19(th) century, and nowadays integrates its nutritional and therapeutic indications to the everyday food choices of several populations. The large number of microorganisms present in kefir and their microbial interactions, the possible bioactive compounds resulting of microbial metabolism, and the benefits associated with the use this beverage confers kefir the status of a natural probiotic, designated as the 21(th) century yoghurt. Several studies have shown that kefir and its constituents have antimicrobial, antitumor, anticarcinogenic and immunomodulatory activity and also improve lactose digestion, among others. This review includes data on the technological aspects, the main beneficial effects on human health of kefir and its microbiological composition. Generally, kefir grains contain a relatively stable and specific microbiota enclosed in a matrix of polysaccharides and proteins. Microbial interactions in kefir are complex due to the composition of kefir grains, which seems to differ among different studies, although some predominant Lactobacillus species are always present. Besides, the specific populations of individual grains seem to contribute to the particular sensory characteristics present in fermented beverages. This review also includes new electron microscopy data on the distribution of microorganisms within different Brazilian kefir grains, which showed a relative change in its distribution according to grain origin.

  3. Russian Kefir Grains Microbial Composition and Its Changes during Production Process.

    Science.gov (United States)

    Kotova, I B; Cherdyntseva, T A; Netrusov, A I

    2016-01-01

    By combining DGGE-PCR method, classical microbiological analysis and light- and electron microscopic observations, it was found that the composition of microbial communities of central Russia regions kefir grains, starter and kefir drink include bacteria of the genera Lactobacillus, Leuconostoc and Lactococcus, and yeast anamorphs of the genera Saccharomyces, Kazachstania and Gibellulopsis. Fifteen prokaryotic and four eukaryotic pure cultures of microorganisms were isolated and identified from kefir grains. It has been shown that members of the genus Lactobacillus prevailed in kefir grains, whereas strains Leuconostoc pseudomesenteroides and Lactococcus lactis dominated in the final product - kefir drink. Yeasts contained in kefir grains in small amounts have reached a significant number of cells in the process of development of this dairy product. The possibility of reverse cell aggregation has been attempted in a mixed cultivation of all isolated pure cultures, but full formation kefir grains is not yet observed after 1.5 years of observation and reinoculations.

  4. SLUDGE TREATMENT PROJECT KOP DISPOSITION - THERMAL AND GAS ANALYSIS FOR THE COLD VACUUM DRYING FACILITY

    Energy Technology Data Exchange (ETDEWEB)

    SWENSON JA; CROWE RD; APTHORPE R; PLYS MG

    2010-03-09

    The purpose of this document is to present conceptual design phase thermal process calculations that support the process design and process safety basis for the cold vacuum drying of K Basin KOP material. This document is intended to demonstrate that the conceptual approach: (1) Represents a workable process design that is suitable for development in preliminary design; and (2) Will support formal safety documentation to be prepared during the definitive design phase to establish an acceptable safety basis. The Sludge Treatment Project (STP) is responsible for the disposition of Knock Out Pot (KOP) sludge within the 105-K West (KW) Basin. KOP sludge consists of size segregated material (primarily canister particulate) from the fuel and scrap cleaning process used in the Spent Nuclear Fuel process at K Basin. The KOP sludge will be pre-treated to remove fines and some of the constituents containing chemically bound water, after which it is referred to as KOP material. The KOP material will then be loaded into a Multi-Canister Overpack (MCO), dried at the Cold Vacuum Drying Facility (CVDF) and stored in the Canister Storage Building (CSB). This process is patterned after the successful drying of 2100 metric tons of spent fuel, and uses the same facilities and much of the same equipment that was used for drying fuel and scrap. Table ES-l present similarities and differences between KOP material and fuel and between MCOs loaded with these materials. The potential content of bound water bearing constituents limits the mass ofKOP material in an MCO load to a fraction of that in an MCO containing fuel and scrap; however, the small particle size of the KOP material causes the surface area to be significantly higher. This relatively large reactive surface area represents an input to the KOP thermal calculations that is significantly different from the calculations for fuel MCOs. The conceptual design provides for a copper insert block that limits the volume available to

  5. Pengaruh pati ganyong (Cannaedulis, Ker modifikasi terhadap kualitas kefir

    Directory of Open Access Journals (Sweden)

    Imam Thohari

    2014-07-01

    Full Text Available The purpose of the research was to determine the effect of using various concentration of modification starch on pH, water content, viscosity and fat content. The research material were kefir made from cow's milk with kefir grains derived from animal product technology laboratory of Animal Husbandry Brawijaya University. The research method was an experimental research with randomized block design. The treatments were the addition of canna starch modification 0% (G0, 0.2% (G1, 0.4% (G2, 0.6% (G3, 0.8% (G4 and 1.0% (G5 of the milk volume. Each treatment was replicated 3 times. The result showed that the addition of modified canna starch provided highly significant effect (p<0.01 on pH, water content, viscosity and fat content. The study concluded that addition of canna starch modification could improve the quality of kefir in terms of pH, water content, and viscosity, protein and lactic acid bacteria. The addition of 1% of canna starch modification had the best kefir quality. Keywords: Kefir, canna starch modification, STTP

  6. Kefir and Cancer: A Systematic Review of Literatures.

    Science.gov (United States)

    Rafie, Nahid; Golpour Hamedani, Sahar; Ghiasvand, Reza; Miraghajani, Maryam

    2015-12-01

    Some studies have suggested chemopreventive effects of kefir, a fermented milk product, on carcinogenesis. The aim of this review study was to evaluate the scientific evidence for effects of kefir on cancer prevention and treatment. We systematically searched for all relevant studies published before June 2015, using PubMed, Google scholar, Cochrane and Science Direct, SID, MedLib and Srlst databases. Relevant studies were reviewed based on systematic review (PRISMA) guidelines. From a total of 2208 papers obtained at the initial database search, 11 publications including 7 in vitro and 4 experimental studies were eligible. In vitro studies on breast, colon, skin and gastric cancers and leukemia cell lines and experimental studies on different sarcomas consistently showed beneficial effects of kefir on cancer prevention and treatment. The results of this systematic review suggest that kefir may be associated with cancer prevention and it also has beneficial effects in cancer treatment. This protection may be associated with kefir bioactive components including peptides, polysaccharides and sphingolipids.

  7. Thermal ecology of Microlophus occipitalis (Sauria: Tropiduridae in the Plain Dry Forest of Tumbes, Peru

    Directory of Open Access Journals (Sweden)

    Juan C. Jordán A.

    2012-10-01

    Full Text Available The thermal ecology of Microlophus occipitalis Peters 1871 in the plain dry forests of Tumbes (northewestern Peru was studied. Mean body temperature was 36.1 ± 1.8 ºC, similar to body temperatures exposed by Microlophus peruvianus in northern Peru. There were no differences between body temperature and degree of thermoregulation of males and females, due to a possible association to their social structure and microhabitat use. Air and substrate temperature affects the body temperature of Microlophus occipitalis, where air temperature accounts for a significant proportion of body temperature variation. We suggest more detailed studies on this lizard species, especially under climate change scenarios in northwestern Peru.

  8. Thermal resistance of naturally occurring airborne bacterial spores. [Viking spacecraft dry heat decontamination simulation

    Science.gov (United States)

    Puleo, J. R.; Bergstrom, S. L.; Peeler, J. T.; Oxborrow, G. S.

    1978-01-01

    Simulation of a heat process used in the terminal dry-heat decontamination of the Viking spacecraft is reported. Naturally occurring airborne bacterial spores were collected on Teflon ribbons in selected spacecraft assembly areas and subsequently subjected to dry heat. Thermal inactivation experiments were conducted at 105, 111.7, 120, 125, 130, and 135 C with a moisture level of 1.2 mg of water per liter. Heat survivors were recovered at temperatures of 135 C when a 30-h heating cycle was employed. Survivors were recovered from all cycles studied and randomly selected for identification. The naturally occurring spore population was reduced an average of 2.2 to 4.4 log cycles from 105 to 135 C. Heating cycles of 5 and 15 h at temperature were compared with the standard 30-h cycle at 111.7, 120, and 125 C. No significant differences in inactivation (alpha = 0.05) were observed between 111.7 and 120 C. The 30-h cycle differs from the 5- and 15-h cycles at 125 C. Thus, the heating cycle can be reduced if a small fraction (about 0.001 to 0.0001) of very resistant spores can be tolerated.

  9. Microbial species diversity, community dynamics, and metabolite kinetics of water kefir fermentation.

    Science.gov (United States)

    Laureys, David; De Vuyst, Luc

    2014-04-01

    Water kefir is a sour, alcoholic, and fruity fermented beverage of which the fermentation is started with water kefir grains. These water kefir grains consist of polysaccharide and contain the microorganisms responsible for the water kefir fermentation. In this work, a water kefir fermentation process was followed as a function of time during 192 h to unravel the community dynamics, the species diversity, and the kinetics of substrate consumption and metabolite production. The majority of the water kefir ecosystem was found to be present on the water kefir grains. The most important microbial species present were Lactobacillus casei/paracasei, Lactobacillus harbinensis, Lactobacillus hilgardii, Bifidobacterium psychraerophilum/crudilactis, Saccharomyces cerevisiae, and Dekkera bruxellensis. The microbial species diversities in the water kefir liquor and on the water kefir grains were similar and remained stable during the whole fermentation process. The major substrate, sucrose, was completely converted after 24 h of fermentation, which coincided with the production of the major part of the water kefir grain polysaccharide. The main metabolites of the fermentation were ethanol and lactic acid. Glycerol, acetic acid, and mannitol were produced in low concentrations. The major part of these metabolites was produced during the first 72 h of fermentation, during which the pH decreased from 4.26 to 3.45. The most prevalent volatile aroma compounds were ethyl acetate, isoamyl acetate, ethyl hexanoate, ethyl octanoate, and ethyl decanoate, which might be of significance with respect to the aroma of the end product.

  10. Kefir induces apoptosis and inhibits cell proliferation in human acute erythroleukemia.

    Science.gov (United States)

    Jalali, Fatemeh; Sharifi, Mohammadreza; Salehi, Rasoul

    2016-01-01

    Acute erythroleukemia is an uncommon subtype of acute myeloid leukemia which has been considered to be a subtype of AML with a worse prognosis. Intensive chemotherapy is the first line of treatment. In recent years, the effect of kefir on some malignancies has been experimented. Kefir is a kind of beverage, which obtained by incubation of kefir grains with raw milk. Kefir grains are a symbiotic complex of different kinds of yeasts and bacteria, especially lactic acid bacteria which gather in a mostly carbohydrate matrix, named kefiran. We investigated the effect of kefir on acute erythroleukemia cell line (KG-1) and peripheral blood mononuclear cells (PBMCs). The cell line and PBMCs were treated with different doses of kefir and milk and incubated for three different times. We used Polymixin B to block the lipopolysaccharide and NaOH (1 mol/l) to neutralize the acidic media. Viability was detected by MTT assay. Apoptosis and necrosis were assessed by annexin-propidium iodide staining. Our results showed that kefir induced apoptosis and necrosis in KG-1 cell line. It was revealed that kefir decreased proliferation in erythroleukemia cell line. We did not observe a remarkable effect of kefir on PBMCs. Our study suggested that kefir may have potential to be an effective treatment for erythroleukemia.

  11. Effect of greenhouse on crop drying under natural and forced convection II. Thermal modeling and experimental validation

    International Nuclear Information System (INIS)

    Jain, Dilip; Tiwari, G.N.

    2004-01-01

    In this paper, mathematical models are presented to study the thermal behavior of crops (cabbage and peas) for open sun drying (natural convection) and inside the greenhouse under both natural and forced convection. The predictions of crop temperature, greenhouse room air temperature and rate of moisture evaporation (crop mass during drying) have been computed in Matlab software on the basis of solar intensity and ambient temperature. The models have been experimentally validated. The predicted crop temperature and crop mass during drying showed fair agreement with experimental values within the root mean square of percent error of 2.98 and 16.55, respectively

  12. Nuclear thermal source transfer unit, post-blast soil sample drying system

    Energy Technology Data Exchange (ETDEWEB)

    Wiser, Ralph S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Valencia, Matthew J [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-01-03

    Los Alamos National Laboratory states that its mission is “To solve national security challenges through scientific excellence.” The Science Undergraduate Laboratory Internship (SULI) programs exists to engage undergraduate students in STEM work by providing opportunity to work at DOE facilities. As an undergraduate mechanical engineering intern under the SULI program at Los Alamos during the fall semester of 2016, I had the opportunity to contribute to the mission of the Laboratory while developing skills in a STEM discipline. I worked with Technology Applications, an engineering group that supports non-proliferation, counter terrorism, and emergency response missions. This group specializes in tool design, weapons engineering, rapid prototyping, and mission training. I assisted with two major projects during my appointment Los Alamos. The first was a thermal source transportation unit, intended to safely contain a nuclear thermal source during transit. The second was a soil drying unit for use in nuclear postblast field sample collection. These projects have given me invaluable experience working alongside a team of professional engineers. Skills developed include modeling, simulation, group design, product and system design, and product testing.

  13. Thermal-hydraulic experiment and analysis for interim dry storage of spent nuclear fuel

    International Nuclear Information System (INIS)

    Yoo, Seung Hun

    2011-02-01

    The experimental and numerical studies of interim storages for nuclear spent fuels have been performed to investigate thermal-hydraulic characteristics of the dry storage systems and to propose new methodologies for the analysis and the design. Three separate researches have been performed in the present study: (a) Development of a scaling methodology and thermal-hydraulic experiment of a single spent fuel assembly simulating a dry storage cask: (b) Full-scope simulation of a dry storage cask by the use of Computational Fluid Dynamics (CFD) code: (c) Thermal-hydraulic design of a tunnel-type interim storage facility. In the first study, a scaling methodology has been developed to design a scaled-down canister. The scaling was performed in two steps. For the first step, the height of a spent fuel assembly was reduced from full height to half height. In order to consider the effect of height reduction on the natural convection, the scaling law of Ishii and Kataoka (1984) was employed. For the second step, the quantity of spent fuel assemblies was reduced from multiple assemblies to a single assembly. The scaling methodology was validated through the comparison with the experiment of the TN24P cask. The Peak Cladding Temperature (PCT), temperature gradients, and the axial and radial temperature distribution in the nondimensional forms were in good agreement with the experimental data. Based on the developed methodology, we have performed a single assembly experiment which was designed to simulate the full scale of the TN24P cask. The experimental data was compared with the CFD calculations. It turns out that their PCTs were less than the maximum allowable temperature for the fuel cladding and that the differences of their PCTs were agreed within 3 .deg. C, which was less than measurement uncertainty. In the second study, the full-scope simulations of the TN24P cask were performed by FLUENT. In order to investigate the sensitivity of the numerical and physical

  14. Kefir treatment ameliorates dextran sulfate sodium-induced colitis in rats.

    Science.gov (United States)

    Senol, Altug; Isler, Mehmet; Sutcu, Recep; Akin, Mete; Cakir, Ebru; Ceyhan, Betul M; Kockar, M Cem

    2015-12-14

    To investigate the preventive effect of kefir on colitis induced with dextran sulfate sodium (DSS) in rats. Twenty-four male Wistar-albino rats were randomized into four groups: normal control, kefir-control, colitis, and kefir-colitis groups. Rats in the normal and kefir-control groups were administered tap water as drinking water for 14 d. Rats in the colitis and kefir-colitis groups were administered a 3% DSS solution as drinking water for 8-14 d to induce colitis. Rats in the kefir-control and kefir-colitis groups were administered 5 mL kefir once a day for 14 d while rats in the normal control and colitis group were administered an identical volume of the placebo (skim milk) using an orogastric feeding tube. Clinical colitis was evaluated with reference to the disease activity index (DAI), based on daily weight loss, stool consistency, and presence of bleeding in feces. Rats were sacrificed on the 15(th) day, blood specimens were collected, and colon tissues were rapidly removed. Levels of myeloperoxidase (MPO), tumor necrosis factor (TNF)-α, interleukin (IL)-10, malondialdehyde, and inducible nitric oxide synthase (iNOS) were measured in colon tissue. The DAI was lower in the kefir-colitis group than in the colitis group (on the 3(rd) and 5(th) days of colitis induction; P kefir-control groups. The DAI was statistically higher only on the 6(th) day in the kefir-colitis group when compared to that in the normal control groups. Increased colon weight and decreased colon length were observed in colitis-induced rats. Mean colon length in the colitis group was significantly shorter than that of the kefir-control group. Kefir treatment significantly decreased histologic colitis scores (P kefir-control group (P Kefir treatment significantly reduced the DSS colitis-induced TNF-α increase (P kefir-colitis groups (P Kefir reduces the clinical DAI and histologic colitis scores in a DSS-induced colitis model, possibly via reduction of MPO, TNF-α, and iNOS levels.

  15. Drying of Rhinacanthus nasutus (Linn. Kurz. using a solar dryer incorporated with a backup thermal energy storage from wood combustion

    Directory of Open Access Journals (Sweden)

    Perapong Tekasakul

    2006-05-01

    Full Text Available An indirect, natural convection, solar cabinet dryer incorporated with a backup thermal energy storage from wood combustion was designed and tested with the Thai herb, Rhinacanthus nasutus (Linn. Kurz. Most of Thai herbs are widely used as traditional medicine and drying is an initial step in the production process. Solar dryer with a biomass backup heating system is the most feasible solution to drying in Thailand. In this work, a 4 m x 5 m solar collector was used to absorb solar radiation for heating the incoming air during the daytime, while a biomass burner was used to supply heat when solar energy was not possible. Heat from fuelwood combustion was accumulated in the thermal storage system made of bricks, and was used to heat up the incoming air. Results showed that the herb was dried uniformly and the temperature inside the drying cabinet could be maintained above 50ºC for more than 10 hours. Thermal efficiency when using solar energy was 10.5%, but the value was less than 1% when using the heat from biomass burning. This resulted from the low moisture content of the products after being dried by the solar energy. The dryer is beneficial to the operators, particularly in southern Thailand, where continuous drying is required. This dryer is by no means limited to drying of the herb. Currently, four dryers of the same model have been used by farmer groups in southern Thailand for drying bananas, several types of herbs, fish, and other products. In economic consideration, its payback period is 5.5 years when compared with the LPG-equipped dryer. When the total cost and production capacity are considered, its payback period is about 6 years.

  16. Peptidomic analysis reveals proteolytic activity of kefir microorganisms on bovine milk proteins.

    Science.gov (United States)

    Dallas, David C; Citerne, Florine; Tian, Tian; Silva, Vitor L M; Kalanetra, Karen M; Frese, Steven A; Robinson, Randall C; Mills, David A; Barile, Daniela

    2016-04-15

    The microorganisms that make up kefir grains are well known for lactose fermentation, but the extent to which they hydrolyze and consume milk proteins remains poorly understood. Peptidomics technologies were used to examine the proteolytic activity of kefir grains on bovine milk proteins. Gel electrophoresis revealed substantial digestion of milk proteins by kefir grains, with mass spectrometric analysis showing the release of 609 protein fragments and alteration of the abundance of >1500 peptides that derived from 27 milk proteins. Kefir contained 25 peptides identified from the literature as having biological activity, including those with antihypertensive, antimicrobial, immunomodulatory, opioid and anti-oxidative functions. 16S rRNA and shotgun metagenomic sequencing identified the principle taxa in the culture as Lactobacillus species. The model kefir sample contained thousands of protein fragments released in part by kefir microorganisms and in part by native milk proteases. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. An innovative approach: cow/oat milk based kefir

    Directory of Open Access Journals (Sweden)

    Nayil Dinkçi

    2015-07-01

    Full Text Available The aim of this study was to evaluate the potential of kefir production using cow-oat milk mixture. Therefore kefir samples with 20, 40 and 60 % of oat milk were produced. The effect of oat-milk ratio on physicochemical, rheological, microbiological and sensory characteristics of the kefir samples was studied during 21 days storage at refrigerated conditions. Increasing oat milk concentration affected the whey-off and apparent viscosity by higher whey off and lower viscosity results. Also the proteolytic activity of the samples was decreased by raising the oat milk concentrations. Increase of the oat milk concentration leaded to a decrease of pH of the samples. Statistical analysis showed that the lactococci and lactobacilli viable cell counts differed among the samples while the highest count was detected in sample with the highest amount of oat milk. The control sample (without oat milk had higher yeast count during the storage period. The final product with 20 % of oat-milk and without addition of flavour was found to be the most acceptable by the sensory panellists. The results indicate the possibility for a new cow/oat milk based kefir.

  18. Administration of probiotic kefir to mice with Clostridium difficile infection exacerbates disease.

    Science.gov (United States)

    Spinler, Jennifer K; Brown, Aaron; Ross, Caná L; Boonma, Prapaporn; Conner, Margaret E; Savidge, Tor C

    2016-08-01

    Lifeway(®) kefir, a fermented milk product containing 12 probiotic organisms, is reported to show promise as an alternative to fecal microbiota transplantation for recurrent Clostridium difficile infection (CDI). We employed a murine CDI model to study the probiotic protective mechanisms and unexpectedly determined that kefir drastically increased disease severity. Our results emphasize the need for further independent clinical testing of kefir as alternative therapy in recurrent CDI. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. The Antimetastatic and Antiangiogenesis Effects of Kefir Water on Murine Breast Cancer Cells.

    Science.gov (United States)

    Zamberi, Nur Rizi; Abu, Nadiah; Mohamed, Nurul Elyani; Nordin, Noraini; Keong, Yeap Swee; Beh, Boon Kee; Zakaria, Zuki Abu Bakar; Nik Abdul Rahman, Nik Mohd Afizan; Alitheen, Noorjahan Banu

    2016-12-01

    Kefir is a unique cultured product that contains beneficial probiotics. Kefir culture from other parts of the world exhibits numerous beneficial qualities such as anti-inflammatory, immunomodulation, and anticancer effects. Nevertheless, kefir cultures from different parts of the world exert different effects because of variation in culture conditions and media. Breast cancer is the leading cancer in women, and metastasis is the major cause of death associated with breast cancer. The antimetastatic and antiangiogenic effects of kefir water made from kefir grains cultured in Malaysia were studied in 4T1 breast cancer cells. 4T1 cancer cells were treated with kefir water in vitro to assess its antimigration and anti-invasion effects. BALB/c mice were injected with 4T1 cancer cells and treated orally with kefir water for 28 days. Kefir water was cytotoxic toward 4T1 cells at IC 50 (half-maximal inhibitory concentration) of 12.5 and 8.33 mg/mL for 48 and 72 hours, respectively. A significant reduction in tumor size and weight (0.9132 ± 0.219 g) and a substantial increase in helper T cells (5-fold) and cytotoxic T cells (7-fold) were observed in the kefir water-treated group. Proinflammatory and proangiogenic markers were significantly reduced in the kefir water-treated group. Kefir water inhibited tumor proliferation in vitro and in vivo mainly through cancer cell apoptosis, immunomodulation by stimulating T helper cells and cytotoxic T cells, and anti-inflammatory, antimetastatic, and antiangiogenesis effects. This study brought out the potential of the probiotic beverage kefir water in cancer treatment. © The Author(s) 2016.

  20. Three-Dimensional Thermal Modeling of Dry Spent Nuclear Fuel Storage Canisters

    International Nuclear Information System (INIS)

    Lee, S.Y.

    1998-05-01

    One of the interim storage configurations being considered for aluminum-clad foreign research reactor fuel, such as the Material and Testing Reactor (MTR) design, is a dry storage facility. To support design studies of storage options, a computational and experimental program was conducted at the Savannah River Site (SRS). The objective was to develop computational fluid dynamics (CFD) conjugate models which would be benchmarked using data obtained from a full scale heat transfer experiment conducted in the SRS Experimental Thermal Fluids Laboratory. The current work describes the modeling approach and presents comparison of computational results with experimental data. The experimental set up consists of an instrumented fuel canister 16 inches in diameter and 36 inches in height.The canister contains a sealed fuel can which is designed to store four fuel assemblies. The fuel assembly heat generation is simulated by an imbeded electrical heater. Each fuel assembly is separated from the others by a stainless steel grid and the assemblies can communicate thermal-hydraulically only through narrow slot holes located at the top and bottom of the assembly. The flow within an enclosed canister is a buoyancy-induced motion resulting from body force acting on density gradients which arise from fluid temperature gradients. The canister is filled with helium or nitrogen gas. The heated canister is surrounded by five unheated dummy canisters and is located inside a wind tunnel. During the test, data are obtained for the radial and axial heat flux/temperature profiles inside the canister, air velocity outside the canister, and ambient air temperature. CFD approach has been used to model the three-dimensional convective velocity and temperature distributions within a single dry storage canister of MTR fuel elements.The final analysis was made for the cases with internal heat source of 85 to 138 watts per MTR fuel element (equivalent to 22 to 35 kW/m3) using various different

  1. Fermentation process for production of apple-based kefir vinegar: microbiological, chemical and sensory analysis.

    Science.gov (United States)

    Viana, Roberta Oliveira; Magalhães-Guedes, Karina Teixeira; Braga, Roberto Alves; Dias, Disney Ribeiro; Schwan, Rosane Freitas

    The aim of this study was to develop a kefir apple-based vinegar and evaluate this fermentation process using new methodology with Biospeckle Laser. Brazilian kefir grains were inoculated in apple must for vinegar production. In this study, the microbial community present in kefir, and correspondent vinegar, was investigated using Matrix Assisted Laser Desorption/Ionization - Time of Flight Mass Spectrometry (MALDI-TOF MS) technique. Saccharomyces cerevisiae, Lactobacillus paracasei, Lactobacillus plantarum, Acetobacter pasteurianus and Acetobacter syzygii were the microbial species identified. S. cerevisiae, L. plantarum, A. pasteurianus and A. syzygii were found in smaller quantities at the beginning of the alcoholic fermentation, but were found throughout the alcoholic and acetic fermentation. Kefir grains were able to utilize apple must as substrate to produce ethanol, and acetic acid. Acetate, volatile alcohols and aldehydes in the vinegar-based kefir were also produced. The yield of acetic acid in the kefir vinegars was ∼79%. The acetic acid concentration was ∼41gL -1 , reaching the required standard for the Brazilian legislation accepts it as vinegar (4.0% acetic acid). Kefir vinegar showed good acceptance in the sensory analysis. The technology proposed here is novel by the application of immobilized-cell biomass (kefir grains) providing a mixed inocula and eliminating the use of centrifuge at the end of the fermentative process. This step will save energy demand and investment. This is the first study to produce apple vinegar using kefir grains. Copyright © 2017. Published by Elsevier Editora Ltda.

  2. Antimicrobial Activity of Kefir against Various Food Pathogens and Spoilage Bacteria.

    Science.gov (United States)

    Kim, Dong-Hyeon; Jeong, Dana; Kim, Hyunsook; Kang, Il-Byeong; Chon, Jung-Whan; Song, Kwang-Young; Seo, Kun-Ho

    2016-01-01

    Kefir is a unique fermented dairy product produced by a mixture of lactic acid bacteria, acetic acid bacteria, and yeast. Here, we compared the antimicrobial spectra of four types of kefirs (A, L, M, and S) fermented for 24, 36, 48, or 72 h against eight food-borne pathogens. Bacillus cereus , Staphylococcus aureus , Listeria monocytogenes , Enterococcus faecalis , Escherichia coli , Salmonella Enteritidis , Pseudomonas aeruginosa , and Cronobacter sakazakii were used as test strains, and antibacterial activity was investigated by the spot on lawn method. The spectra, potencies, and onsets of activity varied according to the type of kefir and the fermentation time. The broadest and strongest antimicrobial spectrum was obtained after at least 36-48 h of fermentation for all kefirs, although the traditional fermentation method of kefir is for 18-24 h at 25℃. For kefir A, B. cereus , E. coli , S . Enteritidis, P. aeruginosa , and C. sakazakii were inhibited, while B. cereus , S. aureus , E. coli , S . Enteritidis, P. aeruginosa , and C. sakazakii were inhibited to different extents by kefirs L, M, and S. Remarkably, S. aureus , S . Enteritidis, and C. sakazakii were only inhibited by kefirs L, M, and S, and L. monocytogenes by kefir M after fermentation for specific times, suggesting that the antimicrobial activity is attributable not only to a low pH but also to antimicrobial substances secreted during the fermentation.

  3. Fermentation process for production of apple-based kefir vinegar: microbiological, chemical and sensory analysis

    Directory of Open Access Journals (Sweden)

    Roberta Oliveira Viana

    Full Text Available Abstract The aim of this study was to develop a kefir apple-based vinegar and evaluate this fermentation process using new methodology with Biospeckle Laser. Brazilian kefir grains were inoculated in apple must for vinegar production. In this study, the microbial community present in kefir, and correspondent vinegar, was investigated using Matrix Assisted Laser Desorption/Ionization - Time of Flight Mass Spectrometry (MALDI-TOF MS technique. Saccharomyces cerevisiae, Lactobacillus paracasei, Lactobacillus plantarum, Acetobacter pasteurianus and Acetobacter syzygii were the microbial species identified. S. cerevisiae, L. plantarum, A. pasteurianus and A. syzygii were found in smaller quantities at the beginning of the alcoholic fermentation, but were found throughout the alcoholic and acetic fermentation. Kefir grains were able to utilize apple must as substrate to produce ethanol, and acetic acid. Acetate, volatile alcohols and aldehydes in the vinegar-based kefir were also produced. The yield of acetic acid in the kefir vinegars was ∼79%. The acetic acid concentration was ∼41 g L-1, reaching the required standard for the Brazilian legislation accepts it as vinegar (4.0% acetic acid. Kefir vinegar showed good acceptance in the sensory analysis. The technology proposed here is novel by the application of immobilized-cell biomass (kefir grains providing a mixed inocula and eliminating the use of centrifuge at the end of the fermentative process. This step will save energy demand and investment. This is the first study to produce apple vinegar using kefir grains.

  4. Intensification of heat transfer during mild thermal treatment of dry-cured ham by using airborne ultrasound.

    Science.gov (United States)

    Contreras, M; Benedito, J; Bon, J; Garcia-Perez, J V

    2018-03-01

    The application of power ultrasound (PuS) could be used as a novel technology with which to intensify thermal treatments using hot air. Mild thermal treatments have been applied to improve the soft texture of dry-cured ham caused by defective processing. In this regard, the aim of this study was to assess the kinetic intensification linked to the application of airborne PuS in the mild thermal treatment using hot air of dry-cured ham. For this purpose, vacuum packed cylindrical samples (2.52±0.11cm in diameter and 1.90±0.14cm in height) of dry-cured ham were heated using hot air at different temperatures (40, 45, 50°C) and air velocities (1, 2, 3, 4, 6m/s) with (22.3kHz, 50W) and without PuS application. Heat transfer was analyzed by considering that it was entirely controlled by conduction and the apparent thermal diffusivity was identified by fitting the model to the heating kinetics. The obtained results revealed that PuS application sped up the heat transfer, showing an increase in the apparent thermal diffusivity (up to 37%). The improvement in the apparent thermal diffusivity produced by PuS application was greater at high temperatures (50°C) but negligible at high air velocities (6m/s). Heating caused an increase in the hardness and elasticity of dry-cured ham, which would correct ham pastiness defects, while the influence of PuS on such textural parameters was negligible. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. High-resolution X-ray computed tomography observations of the thermal drying of lump-sized subbituminous coal

    Energy Technology Data Exchange (ETDEWEB)

    Mathews, Jonathan P. [Department of Energy and Mineral Engineering, Pennsylvania State University, University Park, PA (United States); EMS Energy Institute, University Park, PA (United States); Pone, J. Denis N. [ConocoPhilips Technology Center, Bartlesville, Oklahoma (United States); Mitchell, Gareth D.; Halleck, Phillip [EMS Energy Institute, University Park, PA (United States)

    2011-01-15

    Drying of low-rank coals affects: coal cleaning, combustion, comminution, gasification, liquefaction, and in-seam fluid-flow (water, coalbed methane, and carbon dioxide for sequestration/enhanced coalbed methane). To evaluate the extent of drying-induced transitions, 3 lump-sized (approximately 6 x 2 x 2 cm) Powder River Basin subbituminous coal samples were thermally dried in an air-drying coal oven at 50 C over two weeks. A high-resolution industrial X-ray computed tomography scanner was utilized to generate (non-destructively) three-dimensional regional volumetric renderings, as-received and over 3-stages of drying. The lumps had cleats, both open and mineral filled, with a degree of fracture diversity along the longitudinal plane. Comparison of the virtual slice surfaces, at identifiable locations, allowed the induced cracking and shrinkage accompanying the transitions during 19% moisture loss to almost dry to be observed. Under these drying conditions, the heat transfer, and thus extent of drying, proceeded radially inward. With increased drying time the fractures extend and become larger in aperture as the coal shrinks. The major fractures mostly followed the existing cleat system. With additional drying, these cleats widened and the aperture increase propagated deeper into the coal extended into the butt cleats. New fractures were located mostly perpendicular to the cleat fracture surface. The external volume of the coal lumps had limited shrinkage. The axial extent of the shrinkage length (lump edge to lump edge) was on the order of 4-6%, the bulk of the shrinkage being accommodated by the internal shrinkage between cleats. (author)

  6. A Novel Environmental Route to Ambient Pressure Dried Thermal Insulating Silica Aerogel via Recycled Coal Gangue

    Directory of Open Access Journals (Sweden)

    Pinghua Zhu

    2016-01-01

    Full Text Available Coal gangue, one of the main hazardous emissions of purifying coal from coalmine industry, is rich in silica and alumina. However, the recycling of the waste is normally restricted by less efficient techniques and low attractive output; the utilization of such waste is still staying lower than 15%. In this work, the silica aerogel materials were synthesized by using a precursor extracted from recycled silicon-rich coal gangue, followed by a single-step surface silylation and ambient pressure drying. A low density (~0.19 g/cm3 nanostructured aerogel with a 3D open porous microstructure and high surface area (~690 m2/g was synthesized, which presents a superior thermal insulation performance (~26.5 mW·m−1·K−1 of a plane packed of 4-5 mm granules which was confirmed by transient hot-wire method. This study offers a new facile route to the synthesis of insulating aerogel material by recycling solid waste coal gangue and presents a potential cost reduction of industrial production of silica aerogels.

  7. Multi-criteria decision analysis of concentrated solar power with thermal energy storage and dry cooling.

    Science.gov (United States)

    Klein, Sharon J W

    2013-12-17

    Decisions about energy backup and cooling options for parabolic trough (PT) concentrated solar power have technical, economic, and environmental implications. Although PT development has increased rapidly in recent years, energy policies do not address backup or cooling option requirements, and very few studies directly compare the diverse implications of these options. This is the first study to compare the annual capacity factor, levelized cost of energy (LCOE), water consumption, land use, and life cycle greenhouse gas (GHG) emissions of PT with different backup options (minimal backup (MB), thermal energy storage (TES), and fossil fuel backup (FF)) and different cooling options (wet (WC) and dry (DC). Multicriteria decision analysis was used with five preference scenarios to identify the highest-scoring energy backup-cooling combination for each preference scenario. MB-WC had the highest score in the Economic and Climate Change-Economy scenarios, while FF-DC and FF-WC had the highest scores in the Equal and Availability scenarios, respectively. TES-DC had the highest score for the Environmental scenario. DC was ranked 1-3 in all preference scenarios. Direct comparisons between GHG emissions and LCOE and between GHG emissions and land use suggest a preference for TES if backup is require for PT plants to compete with baseload generators.

  8. Investigating the Plasma-Assisted and Thermal Catalytic Dry Methane Reforming for Syngas Production: Process Design, Simulation and Evaluation

    Directory of Open Access Journals (Sweden)

    Evangelos Delikonstantis

    2017-09-01

    Full Text Available The growing surplus of green electricity generated by renewable energy technologies has fueled research towards chemical industry electrification. By adapting power-to-chemical concepts, such as plasma-assisted processes, cheap resources could be converted into fuels and base chemicals. However, the feasibility of those electrified processes at large scale has not been investigated yet. Thus, the current work strives to compare, for first time in the literature, plasma-assisted production of syngas, from CH4 and CO2 (dry methane reforming, with thermal catalytic dry methane reforming. Specifically, both processes are conceptually designed to deliver syngas suitable for methanol synthesis (H2/CO ≥ 2 in mole. The processes are simulated in the Aspen Plus process simulator where different process steps are investigated. Heat integration and equipment cost estimation are performed for the most promising process flow diagrams. Collectively, plasma-assisted dry methane reforming integrated with combined steam/CO2 methane reforming is an effective way to deliver syngas for methanol production. It is more sustainable than combined thermal catalytic dry methane reforming with steam methane reforming, which has also been proposed for syngas production of H2/CO ≥ 2; in the former process, 40% more CO2 is captured, while 38% less H2O is consumed per mol of syngas. Furthermore, the plasma-assisted process is less complex than the thermal catalytic one; it requires higher amount of utilities, but comparable capital investment.

  9. Characteristics of ammonia emission during thermal drying of lime sludge for co-combustion in cement kilns.

    Science.gov (United States)

    Liu, Wei; Xu, Jingcheng; Liu, Jia; Cao, Haihua; Huang, Xiang-Feng; Li, Guangming

    2015-01-01

    Thermal drying was used to reduce sludge moisture content before co-combustion in cement kilns. The characteristics of ammonia (NH3) emission during thermal drying of lime sludge (LS) were investigated in a laboratory-scale tubular dry furnace under different temperature and time conditions. As the temperature increased, the NH3 concentration increased in the temperature range 100-130°C, decreased in the temperature range 130-220°C and increased rapidly at >220°C. Emission of NH3 also increased as the lime dosage increased and stabilized at lime dosages>5%. In the first 60 min of drying experiments, 55% of the NH3 was released. NH3 accounted for about 67-72% of the change in total nitrogen caused by the release of nitrogen-containing volatile compounds (VCs) from the sludge. X-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy revealed that the main forms of nitrogen in sludge were amides and amines. The addition of lime (CaO) could cause conversion of N-H, N-O or C-N containing compounds to NH3 during the drying process.

  10. Effect of kefir on Fusobacterium nucleatum in potentially preventing intestinal cancer

    Directory of Open Access Journals (Sweden)

    Zeynep Banu Guzel-Seydim

    2016-07-01

    Full Text Available Background: Fusobacterium spp. are known to be part of mouth and intestinal microbiota. Fusobacterium nucleatum is an obligate anaerobe, Gram negative, non-spore forming pleomorphic bacillus that can cause diseases not only in the mouth and teeth but also in the brain, pleura, lungs and liver. It was noted that F. nucleatum induces fetal death (fetal demise in pregnant women. Recent studies indicate that F. nucleatum could lead to colon cancer by binding to the epithelial tissue. Kefir is produced from kefir grains that are a source of probiotics. Fermented dairy products and especially kefir and yogurt are significant for functional nutrition. In kefir grains, lactic acid bacteria, acetic acid bacteria and yeasts are embedded in a polysaccharide matrix, called kefiran. When kefir grains are added to milk and incubated for approximately 22 h at 25°C, microorganisms in the grains continue to proliferate in milk with the production of functional metabolic compounds. While yogurt has mainly two bacteria, authentic kefir has its characteristic Lactobacillus kefiranofaciens, Lactobacillus kefir and Lactobacillus kefirgranum, in addition to many other types of lactic acid bacteria (LAB. Previous studies have indicated that fermented dairy products can cause probiotic effects such as improvement in digestive system health, reduction in serum cholesterol, improvement in lactose tolerance, improvement in immune function, control of irritable bowel symptoms, and anticarcinogenic properties. Objective: The aim of this research was to report the effects of fermented dairy products in vitro on the growth of F. nucleatum. Milk, kefir made from natural kefir grains, commercial kefir produced from kefir starter culture, yogurt produced from natural yogurt starter culture and commercial yogurt produced from yogurt starter culture were used against F. nucleatum. Methods: F. nucleatum (ATCC 25586 was grown in Fluid Thioglycollate Medium at 37°C for 3 days under

  11. Thermal/moisture-related stresses and fracture behaviour in solid wood members during forced drying

    DEFF Research Database (Denmark)

    Larsen, Finn

    with a drying history that was generated, to verify a model that was used to simulate disc samples of the same type. The stresses were analyzed so as to clarify whether and when critical stress stateswere encountered during the drying process. The reversibility of the mechano-sorptive strains, i...... of wood without injury to the timber itself. When solid wood products are dried from a green condition down to an average moisture content level close to the service life conditions of the final product, significant moisture-induced stresses and related fracturing can occur. The drying stresses arise......, in particular the stress and cracking that takeplace during kiln-drying. Both experimental and numerical work was carried out so as to obtain knowledge regarding stress, strain, mechano-sorption and crackbehaviours in wood during drying.The investigations aimed also at revealing how drying damagecan best...

  12. KEFIRS MANUFACTURED FROM CAMEL (CAMELUS DRAMEDARIUS MILK AND COW MILK: COMPARISON OF SOME CHEMICAL AND MICROBIAL PROPERTIES

    Directory of Open Access Journals (Sweden)

    G. Kavas

    2015-09-01

    Full Text Available This study examined the production possibilities of kefir from fresh camel milk fermented with grain. The findings were then compared with kefir manufactured from cow’s milk. Cow’s milk was fermented with 2.5% grains. The 1% (v/w glucose enriched camel’s milk was fermented with 10% grains and left in an incubator at 25°C. Physical-chemical and sensorial analyses of the kefir sampleswere measured on day one (18 hours of storage and microbiological analyses were measured on days one, three and five. Some physical-chemical parameters were found to be higherin camel milk and its kefir than in cow milk and its kefir, some were found to be close and some were found to be lower. Addition of 1% glucose and 10% grains to the camel milk affected the titrationacidity and viscosity of kefir to significant levels. The kefir produced from camel milk was perceived as sourer, whereas its other properties were found to be close to those of cow milk. Thecholesterol levels of camel milk and its kefir were detected to be higher when compared to those of cow milk and its kefir, but the cholesterol level decreased in both examples after the productionof kefir. In terms of the composition of fatty acids, it was determined that SFA and the small, medium chain fatty acids ratio was low in camel milk and its kefir, but MUFA and the long chainfatty acids ratio was high. PUFA ratio was high in camel milk but low in its kefir. In microbiological analysis, yeast levels increased in kefir samples with the Lactobacillus ssp. strains, and theincrease in the number of yeasts was higher than in the cow milk kefir. In kefir samples, Lactobacillus ssp. strains increased on day one and three of storage, but diminished after day three.

  13. Administration of kefir-fermented milk protects mice against Giardia intestinalis infection.

    Science.gov (United States)

    Franco, Mariana Correa; Golowczyc, Marina A; De Antoni, Graciela L; Pérez, Pablo F; Humen, Martín; Serradell, María de los Angeles

    2013-12-01

    Giardiasis, caused by the protozoan Giardia intestinalis, is one of the most common intestinal diseases worldwide and constitutes an important problem for the public health systems of various countries. Kefir is a probiotic drink obtained by fermenting milk with 'kefir grains', which consist mainly of bacteria and yeasts that coexist in a complex symbiotic association. In this work, we studied the ability of kefir to protect mice from G. intestinalis infection, and characterized the host immune response to this probiotic in the context of the intestinal infection. Six- to 8-week-old C75BL/6 mice were separated into four groups: controls, kefir mice (receiving 1 : 100 dilution of kefir in drinking water for 14 days), Giardia mice (infected orally with 4×10(7) trophozoites of G. intestinalis at day 7) and Giardia-kefir mice (kefir-treated G. intestinalis-infected mice), and killed at 2 or 7 days post-infection. Kefir administration was able to significantly reduce the intensity of Giardia infection at 7 days post-infection. An increase in the percentage of CD4(+) T cells at 2 days post-infection was observed in the Peyer's patches (PP) of mice belonging to the Giardia group compared with the control and kefir groups, while the percentage of CD4(+) T cells in PP in the Giardia-kefir group was similar to that of controls. At 2 days post-infection, a reduction in the percentage of B220-positive major histocompatibility complex class II medium cells in PP was observed in infected mice compared with the other groups. At 7 days post-infection, Giardia-infected mice showed a reduction in RcFcε-positive cells compared with the control group, suggesting a downregulation of the inflammatory response. However, the percentages of RcFcε-positive cells did not differ from controls in the kefir and Giardia-kefir groups. An increase in IgA-positive cells was observed in the lamina propria of the kefir group compared with controls at 2 days post-infection. Interestingly, the

  14. CFD simulation of a dry scroll vacuum pump with clearances, solid heating and thermal deformation

    Science.gov (United States)

    Spille-Kohoff, A.; Hesse, J.; Andres, R.; Hetze, F.

    2017-08-01

    Although dry scroll vacuum pumps (DSPV) are essential devices in many different industrial processes, the CFD simulation of such pumps is not widely used and often restricted to simplified cases due to its complexity: The working principle with a fixed and an orbiting scroll leads to working chambers that are changing in time and are connected through moving small radial and axial clearances in the range of 10 to 100 μm. Due to the low densities and low mass flow rates in vacuum pumps, it is important to include heat transfer towards and inside the solid components. Solid heating is very slow compared to the scroll revolution speed and the gas behaviour, thus a special workflow is necessary to reach the working conditions in reasonable simulation times. The resulting solid temperature is then used to compute the thermal deformation, which usually results in gap size changes that influence leakage flows. In this paper, setup steps and results for the simulation of a DSVP are shown and compared to theoretical and experimental results. The time-varying working chambers are meshed with TwinMesh, a hexahedral meshing programme for positive displacement machines. The CFD simulation with ANSYS CFX accounts for gas flow with compressibility and turbulence effects, conjugate heat transfer between gas and solids, and leakage flows through the clearances. Time-resolved results for torques, chamber pressure, mass flow, and heat flow between gas and solids are shown, as well as time- and space-resolved results for pressure, velocity, and temperature for different operating conditions of the DSVP.

  15. Comparative study of microbiological, chemical and sensory properties of kefirs produced in Estonia, Latvia and Lithuania.

    Science.gov (United States)

    Anton, Dea; Raudsepp, Piret; Roasto, Mati; Meremäe, Kadrin; Kuusik, Sirje; Toomik, Peeter; Elias, Priit; Laikoja, Katrin; Kaart, Tanel; Lepiku, Martin; Püssa, Tõnu

    2016-02-01

    In the current study the microbiological, sensory and chemical properties of 24 kefirs (12 producers) from Estonian, Latvian and Lithuanian retail market were determined using gas chromatography (GC), high performance liquid chromatography (HPLC-MS/MS-Q-TOF and LC-ion trap MS/MS), spectrophotometry and other methods. Antihypertensive, angiotensin-converting enzyme (ACE) inhibiting, antioxidant and antibacterial peptides were found in the kefir samples. According to the results of principal component analysis of 200 most abundant compounds obtained with HPLC-MS/MS-Q-TOF analysis, Estonian kefirs differed from the rest. Kefirs of Latvian and Lithuanian origin showed similarities in several characteristics, probably related to the starter cultures and technological processes. The fatty acids composition of all Baltic kefirs was uniform. The antioxidant capacity of the kefirs varied slightly, whereas intermediate positive correlation (r = 0.32, P < 0.05) was found between antioxidativity and total bacterial count. The lipid oxidation level, estimated as the content of linoleic and oleic acid primary oxidation products, oxylipins, was very low in all studied kefirs. Only one third of analysed kefirs met the requirements of the minimum sum of viable microorganisms, indicated in the Codex Standard for Fermented Milks.

  16. Biological activity of the non-microbial fraction of kefir: antagonism against intestinal pathogens.

    Science.gov (United States)

    Iraporda, Carolina; Abatemarco Júnior, Mário; Neumann, Elisabeth; Nunes, Álvaro Cantini; Nicoli, Jacques R; Abraham, Analía G; Garrote, Graciela L

    2017-08-01

    Kefir is a fermented milk obtained by the activity of kefir grains which are composed of lactic and acetic acid bacteria, and yeasts. Many beneficial health effects have been associated with kefir consumption such as stimulation of the immune system and inhibition of pathogenic microorganisms. The biological activity of kefir may be attributed to the presence of a complex microbiota as well as the microbial metabolites that are released during fermentation. The aim of this work was to characterise the non-microbial fraction of kefir and to study its antagonism against Escherichia coli, Salmonella spp. and Bacillus cereus. During milk fermentation there was a production of organic acids, mainly lactic and acetic acid, with a consequent decrease in pH and lactose content. The non-microbial fraction of kefir added to nutrient broth at concentrations above 75% v/v induced a complete inhibition of pathogenic growth that could be ascribed to the presence of un-dissociated lactic acid. In vitro assays using an intestinal epithelial cell model indicated that pre-incubation of cells with the non-microbial fraction of kefir did not modify the association/invasion of Salmonella whereas pre-incubation of Salmonella with this fraction under conditions that did not affect their viability significantly decreased the pathogen's ability to invade epithelial cells. Lactate exerted a protective effect against Salmonella in a mouse model, demonstrating the relevance of metabolites present in the non-microbial fraction of kefir produced during milk fermentation.

  17. Kefir grains as a starter for whey fermentation at different temperatures: chemical and microbiological characterisation.

    Science.gov (United States)

    Londero, Alejandra; Hamet, María F; De Antoni, Graciela L; Garrote, Graciela L; Abraham, Analía G

    2012-08-01

    We report here a comparative analysis of the growth, acidification capacity, and chemical and microbiologic composition between kefir grains after 20 subcultures in whey at 20, 30, and 37°C and the original kefir grains coming from milk along with a determination of the microbiological composition of the fermented whey as compared with that of traditional fermented milk. When fermentation was carried out repeatedly at 30 or 37°C, kefir grains changed their kefir-like appearance, exhibited reduced growth rates, had a lower diversity of yeasts and water content, and a higher protein-to-polysaccharide ratio compared with the original kefir grains. In contrast, at 20°C kefir grains could remain in whey for prolonged periods without altering their acidification capacity, growth rate, macroscopic appearance or chemical and microbiologic composition-with the only difference being a reduction in certain yeast populations after 20 subcultures in whey. At this incubation temperature, the presence of Lactobacillus kefiranofaciens, Lb. kefir, Lb. parakefir, Lactococcus lactis, Kluyveromyces marxianus, Saccharomyces unisporus, and Sac. cerevisiae was detected in kefir grains and in fermented whey by denaturing-gradient-gel electrophoresis (DGGE). In whey fermented at 20°C the number of lactic-acid bacteria (LAB) was significantly lower (Pkefir grains as whey-fermentation starters.

  18. Growth Inhibition of Cronobacter sakazakii in Experimentally Contaminated Powdered Infant Formula by Kefir Supernatant.

    Science.gov (United States)

    Kim, Dong-Hyeon; Chon, Jung-Whan; Kang, Il-Byeong; Kim, Hyunsook; Kim, Hong-Seok; Song, Kwang-Young; Seo, Kun-Ho

    2015-09-01

    Kefir is a type of fermented milk containing lactic and acetic acid bacteria and yeast. In this study, we evaluated the antimicrobial activity of kefir supernatant against Cronobacter sakazakii in powdered infant formula (PIF). In a spot-on-lawn test, the growth of 20 C. sakazakii strains, including 10 clinical and 10 food isolates, was completely inhibited in the presence of kefir supernatant. Significant differences in the diameters of inhibition zones were observed upon treatment with kefir compared with the results for Lactobacillus kefiri and Candida kefyr culture supernatants or solutions of lactic and acetic acid and ethyl alcohol in the agar well diffusion test (P kefir supernatant to 1 ml of nutrient broth completely inhibited the growth of C. sakazakii, as evaluated by spectrophotometry. The antimicrobial activity of kefir supernatant in experimentally contaminated PIF was also tested; we found no viable C. sakazakii cells remaining in PIF rehydrated with 30% kefir supernatant solution for 1 h, demonstrating that the antimicrobial activity of kefir supernatant against C. sakazakii could be applied in real food samples.

  19. Identification of some kefir microorganisms and optimization of their production in sugarcane juice

    Directory of Open Access Journals (Sweden)

    Blanca Cecilia Salazar Alzate

    2016-07-01

    Full Text Available Kefir grains are a consortium of bacteria and yeasts grouped in a polysaccharide called kefirano. They ferment sugar substrates to produce organic acids, CO2, vitamins and ethanol. They also have positive effects on health. This research project aimed to optimize the fermentation process of sugarcane concentrate using kefir grains. The microorganisms were first identified morphologically and biochemically, then isolated and purified in selective media. Optimization was conducted using the response surface methodology with a composite central design. The independent variables were: temperature, time and percentage of kefir grains added. As for dependent variables, we considered the following: increase in kefir grains (also measured as a percentage, acidity and microbial growth. Additionally, our study identified populations of Lactobacillus curvatus and the following yeasts: Candida famata, Can. magnoliae, Can. krusei/incospicua and Can. sphaerica in the kefir grains. The optimal conditions were 33.5 °C, 30 h and 6% w/w of added kefir grains. The increase in kefir grains reached was of 193 ± 12%. The lactobacilli, lactococci and yeast counts were 1.57x108, 8.63x107 and 2.05x107 CFU mL-1 respectively. Experimental optimization was an effective tool for the fermentation of kefir grains in sugarcane concentrate.

  20. AVALIAÇÃO DA ADIÇÃO DO KEFIR EM DIETA HOSPITALAR

    OpenAIRE

    Joice de Fátima Laureano Martins; Eduarda Marinho; Heloísa Helena Firmino; Viviane da Cruz Rafael; Célia Lúcia de Luces Fortes Ferreira

    2012-01-01

    Os grãos de kefir são utilizados na elaboração de um produto lácteo fermentado o qual denominamos kefir. Sua introdução em dietas hospitalares promove vários benefícios aos pacientes e possui grande capacidade de estimular o sistema imunológico. Objetivou-se verificar a aceitação de diferentes formulações tendo como ingrediente o kefir. Os grãos de kefir (5 %) foram cultivados por 24 horas à temperatura de 22º C. Em seguida, foram preparadas quatro formulações. Formulação 1 - 50 % de kefir cu...

  1. Kefir prevented excess fat accumulation in diet-induced obese mice.

    Science.gov (United States)

    Choi, Jae-Woo; Kang, Hye Won; Lim, Won-Chul; Kim, Mi-Kyoung; Lee, In-Young; Cho, Hong-Yon

    2017-05-01

    Excessive body fat accumulation can result in obesity, which is a serious health concern. Kefir, a probiotic, has recently shown possible health benefits in fighting obesity. This study investigated the inhibitory effects of 0.1 and 0.2% kefir powder on fat accumulation in adipose and liver tissues of high-fat diet (HFD)-induced obese mice. Kefir reduced body weight and epididymal fat pad weight and decreased adipocyte diameters in HFD-induced obese mice. This was supported by decreased expression of genes related to adipogenesis and lipogenesis as well as reduced proinflammatory marker levels in epididymal fat. Along with reduced hepatic triacylglycerol concentrations and serum alanine transaminase and aspartate transaminase activities, genes related to lipogenesis and fatty acid oxidation were downregulated and upregulated, respectively, in liver tissue. Kefir also decreased serum triacylglycerol, total cholesterol, and low-density lipoprotein-cholesterol concentrations. Overall, kefir has the potential to prevent obesity.

  2. The Microbiota and Health Promoting Characteristics of the Fermented Beverage Kefir.

    Science.gov (United States)

    Bourrie, Benjamin C T; Willing, Benjamin P; Cotter, Paul D

    2016-01-01

    Kefir is a complex fermented dairy product created through the symbiotic fermentation of milk by lactic acid bacteria and yeasts contained within an exopolysaccharide and protein complex called a kefir grain. As with other fermented dairy products, kefir has been associated with a range of health benefits such as cholesterol metabolism and angiotensin-converting enzyme (ACE) inhibition, antimicrobial activity, tumor suppression, increased speed of wound healing, and modulation of the immune system including the alleviation of allergy and asthma. These reports have led to increased interest in kefir as a focus of research and as a potential probiotic-containing product. Here, we review those studies with a particular emphasis on the microbial composition and the health benefits of the product, as well as discussing the further development of kefir as an important probiotic product.

  3. The Microbiota and health promoting characteristics of the fermented beverage Kefir.

    Directory of Open Access Journals (Sweden)

    Benjamin C.T. Bourrie

    2016-05-01

    Full Text Available Kefir is a complex fermented dairy product created through the symbiotic fermentation of milk by lactic acid bacteria and yeasts contained within an exopolysaccharide and protein complex called a kefir grain. As with other fermented dairy products, kefir has been associated with a range of health benefits such as cholesterol metabolism and angiotensin-converting enzyme (ACE inhibition, antimicrobial activity, tumor suppression, increased speed of wound healing, and modulation of the immune system including the alleviation of allergy and asthma. These reports have led to increased interest in kefir as a focus of research and as a potential probiotic-containing product. Here, we review those studies with a particular emphasis on the microbial composition and the health benefits of the product, as well as discussing the further development of kefir as an important probiotic product.

  4. Antidiabetic Potential of Kefir Combination from Goat Milk and Soy Milk in Rats Induced with Streptozotocin-Nicotinamide

    Science.gov (United States)

    Harmayani, Eni; Sunarti

    2015-01-01

    The study aimed to evaluate the effect of kefir combination from goat milk and soy milk on lipid profile, plasma glucose, glutathione peroxidase (GPx) activity and the improvement of pancreatic β-cell in diabetic rats. Male rats were divided into five treatments: normal control, diabetic control, goat milk kefir, combination of goat milk-soy milk kefir and soy milk kefir. All rats were induced by streptooztocin-nicotinamide (STZ-NA), except for normal control. After 35 d experiment, the rats were sampled for blood, sacrificed and sampled for pancreatic tissues. Results showed that diabetic rats fed kefir combination had higher (pmilk or soy milk kefir. Decreasing of plasma glucose in diabetic rats fed kefir combination was higher (p<0.05) than rats fed goat millk kefir. The activity of GPx in diabetic rats fed three kinds of kefir were higher (p<0.01) than untreated diabetic rats. The average number of Langerhans and β-cells in diabetic rats fed kefir combination was the same as the normal control, but it was higher than diabetic control. It was concluded that kefir combination can be used as antidiabetic through maintaining in serum triglyceride, decreasing in plasma glucose, increasing in GPx activity and improving in pancreatic β-cells. PMID:26877646

  5. DESIGN AND THERMAL PERFORMANCE OF THE SOLAR BIOMASS HYBRID DRYER FOR CASHEW DRYING

    Directory of Open Access Journals (Sweden)

    Saravanan Dhanuskodi

    2014-12-01

    Full Text Available Drying of Cashew nut to remove testa is one of the most energy-intensive processes of cashew nut process industry. For this reason a hybrid dryer consisting of a solar flat plate collector, a biomass heater and a drying chamber is designed and fabricated. 40 kg of Cashew nut with initial moisture of 9 % is used in the experiment. The performance test of the dryer is carried out in two modes of operation: hybrid-forced convection and hybrid-natural convection. Drying time and drying efficiency during these two modes of operation are estimated and compared with the sun drying. The system is capable of attaining drying temperature between 50º and 70ºC. In the hybrid forced drying, the required moisture content of 3% is achieved within 7 hours and the average system efficiency is estimated as 5.08%. In the hybrid natural drying, the required moisture content is obtained in 9 hours and the average system efficiency is 3.17%. The fuel consumption during the drying process is 0.5 kg/hr and 0.75 kg/hr for forced mode and natural mode, respectively. The drying process in the hybrid forced mode of operation is twice faster than the sun drying. The dryer can be operated in any climatic conditions: as a solar dryer on normal sunny days, as a biomass dryer at night time and as a hybrid dryer on cloudy days. Based on the experimental study, it is concluded that the developed hybrid dryer is suitable for small scale cashew nut farmers in rural areas of developing countries.

  6. Biosurfactant production by Pseudomonas aeruginosain kefir and fish meal

    Science.gov (United States)

    Kaskatepe, Banu; Yildiz, Sulhiye; Gumustas, Mehmet; Ozkan, Sibel A.

    2015-01-01

    The aim of this study was to increase rhamnolipid production by formulating media using kefir and fish meal for Pseudomonas aeruginosa strains isolated from different environmental resources. The strains, named as H1, SY1, and ST1, capable of rhamnolipid production were isolated from soil contaminated with wastes originating from olive and fish oil factories. Additionally, P. aeruginosa ATCC 9027 strain, which is known as rhamnolipid producer, was included in the study. Initially, rhamnolipid production by the strains was determined in Mineral Salt Medium (MSM) and then in media prepared by using kefir and fish meal. The obtained rhamnolipids were purified and quantified according to Dubois et al. (1956). The quantity of rhamnolipids of ATCC, H1 and SY1 strains in kefir media were determined as 11.7 g/L, 10.8 g/L and 3.2 g/L, respectively, and in fish meal media as 12.3 g/L, 9.3 g/L and 10.3 g/L, respectively. In addition, effect of UV light exposure on rhamnolipid production was also investigated but contrary a decrease was observed. The results indicate that P. aeruginosa strains isolated from various environmental resources used in this study can be important due to their rhamnolipid yield, and fish meal, which is obtained from waste of fish, can be an alternative source in low cost rhamnolipid production. PMID:26413070

  7. Biosurfactant production by Pseudomonas aeruginosain kefir and fish meal

    Directory of Open Access Journals (Sweden)

    Banu Kaskatepe

    2015-09-01

    Full Text Available The aim of this study was to increase rhamnolipid production by formulating media using kefir and fish meal for Pseudomonas aeruginosa strains isolated from different environmental resources. The strains, named as H1, SY1, and ST1, capable of rhamnolipid production were isolated from soil contaminated with wastes originating from olive and fish oil factories. Additionally, P. aeruginosa ATCC 9027 strain, which is known as rhamnolipid producer, was included in the study. Initially, rhamnolipid production by the strains was determined in Mineral Salt Medium (MSM and then in media prepared by using kefir and fish meal. The obtained rhamnolipids were purified and quantified according to Dubois et al. (1956. The quantity of rhamnolipids of ATCC, H1 and SY1 strains in kefir media were determined as 11.7 g/L, 10.8 g/L and 3.2 g/L, respectively, and in fish meal media as 12.3 g/L, 9.3 g/L and 10.3 g/L, respectively. In addition, effect of UV light exposure on rhamnolipid production was also investigated but contrary a decrease was observed. The results indicate that P. aeruginosa strains isolated from various environmental resources used in this study can be important due to their rhamnolipid yield, and fish meal, which is obtained from waste of fish, can be an alternative source in low cost rhamnolipid production.

  8. Effect of drying temperatures on starch-related functional and thermal properties of acorn flours.

    Science.gov (United States)

    Correia, P R; Beirão-da-Costa, M L

    2011-03-01

    The application of starchy flours from different origins in food systems depends greatly on information about the chemical and functional properties of such food materials. Acorns are important forestry resources in the central and southern regions of Portugal. To preserve these fruits and to optimize their use, techniques like drying are needed. The effects of different drying temperatures on starch-related functional properties of acorn flours obtained from dried fruits of Quercus rotundifolia (QR) and Quercus suber (QS) were evaluated. Flours were characterized for amylose and resistant starch (RS) contents, swelling ability, and gelatinization properties. Drying temperature mainly affected amylose content and viscoamylographic properties. Amylograms of flours from fruits dried at 60 °C displayed higher consistency (2102 B.U. and 1560 B.U., respectively, for QR and QS). The transition temperatures and enthalpy were less affected by drying temperature, suggesting few modifications in starch structure during drying. QR flours presented different functional properties to those obtained from QS acorn flours. The effect of drying temperatures were more evident in QR.

  9. Active layer thermal monitoring of a Dry Valley of the Ellsworth Mountains, Continental Antarctica

    Science.gov (United States)

    Schaefer, Carlos Ernesto; Michel, Roberto; Souza, Karoline; Senra, Eduardo; Bremer, Ulisses

    2015-04-01

    daily average in late December 2012, reaching a minimum in mid July 2013 on P1 (10.9 °C, -37.9 °C, ± 11.1) and P2 (6.9 °C, -37.1 °C, ± 10.2). The active layer thickness reaches a maximum of 48.4 cm at P1 on January 17th 2013 and 47.8 cm at P2 on January 7th 2012. No ID were recorded for the studied period, one TD was recorded at 5 cm on P2, 143 FTD were recorded at 5 cm, 81 at 10 cm and 46 days at 30 cm on P1, on P2 118 FTD were recorded at 5 cm, 80 at 10 cm and 42 days at 30 cm. The majority of the days were classified as FD for both sites; 585 at 5 cm, 647 at 10 cm and 684 days at 30 cm on P1, on P2 611 FD were recorded at 5 cm, 650 at 10 cm and 688 days at 30 cm. Only 17 FTD were recorded for the air temperature and 713 FD. Over the 728 days of the studied period the sum of all positive daily average temperatures was 166.3 TDD at 5 cm and 23.8 TDD at 10 cm on P1, 45.0 TDD at 5 cm and 5.2 TDD at 10 cm on P2. No positive daily average was recorded at 30 cm for both sites. The sum of all negative daily average temperatures was -13504.5 FDD at 5 cm, -13389.9 FDD at 10 cm and -13381.0 FDD at 30 cm on P1, -13508.0 FDD at 5 cm, -13486.6 FDD at 10 cm and -13398.9 FDD at 30 cm on P2. Only 0.28 TDD were summed for the air temperature and -14430.7 FDD. The soil thermal regime at the dry valley of Edson Hill, Ellsworth Mountains is characteristic of polar desert affected by Dry-frozen permafrost. Although air temperature does not reach high positive values, variations in soil temperature are more intense during the year, showing the soil's response to solar radiation.

  10. Kefir induces cell-cycle arrest and apoptosis in HTLV-1-negative malignant T-lymphocytes

    Directory of Open Access Journals (Sweden)

    Katia Maalouf

    2011-02-01

    Full Text Available Katia Maalouf1, Elias Baydoun2, Sandra Rizk11Department of Natural Sciences, Lebanese American University, Beirut, Lebanon; 2Department of Biology, American University of Beirut, Beirut, LebanonBackground: Adult lymphoblastic leukemia (ALL is a malignancy that occurs in white blood cells. The overall cure rate in children is 85%, whereas it is only 40% in adults. Kefir is an important probiotic that contains many bioactive ingredients, which give it unique health benefits. It has been shown to control several cellular types of cancer.Purpose: The present study investigates the effect of a cell-free fraction of kefir on CEM and Jurkat cells, which are human T-lymphotropic virus type I (HTLV-1-negative malignant T-lymphocytes.Methods: Cells were incubated with different kefir concentrations. The cytotoxicity of the compound was evaluated by determining the percentage viability of cells. The effect of all the noncytotoxic concentrations of kefir on the proliferation of CEM and Jurkat cells was then assessed. The levels of transforming growth factor-alpha (TGF-α, transforming growth factor- beta1 (TGF-β1, matrix metalloproteinase-2 (MMP-2, and MMP-9 mRNA upon kefir treatment were then analyzed using reverse transcriptase polymerase chain reaction (RT-PCR. Finally, the growth inhibitory effects of kefir on cell-cycle progression/apoptosis were assessed by Cell Death Detection (ELISA and flow cytometry.Results: The maximum cytotoxicity recorded after 48-hours treatment with 80 µg/µL kefir was only 42% and 39% in CEM and Jurkat cells, respectively. The percent reduction in proliferation was very significant, and was dose-, and time-dependent. In both cell lines, kefir exhibited its antiproliferative effect by downregulating TGF-α and upregulating TGF- β1 mRNA expression. Upon kefir treatment, a marked increase in cell-cycle distribution was noted in the preG1 phase of CEM and Jurkat cells, indicating the proapoptotic effect of kefir, which was

  11. Physicochemical and thermal properties of taro (Colocasia esculenta sp) powders as affected by state of maturity and drying method.

    Science.gov (United States)

    Himeda, M; Njintang, Y N; Gaiani, C; Nguimbou, R M; Scher, J; Facho, B; Mbofung, C M F

    2014-09-01

    The study was aimed at determining the effect of harvesting time and drying method on the thermal and physicochemical properties of taro powder, Sosso ecotype. A 5 × 2 factorial experiment with 5 harvesting times (6, 7, 8, 9 and 10 months after planting) and 2 drying methods (sun and electric oven drying) was used for this purpose. The variance component analysis revealed harvesting time as the most important factor affecting all the variables measured. In particular the proteins and available sugar contents of the powders increased significantly with increase in harvesting time. The same was true of the gelling property and water absorption capacity of the powders. It was equally observed that the temperatures (start, peak and end) and enthalpy of gelatinization of the powders increased with harvesting time. It is concluded that harvesting sosso-taro at full maturity (10 months after planting) and sun-drying produces food powders with excellent gelling properties among others.

  12. Microbiological, biochemical, and functional aspects of sugary kefir fermentation - A review.

    Science.gov (United States)

    Fiorda, Fernanda Assumpção; de Melo Pereira, Gilberto Vinicius; Thomaz-Soccol, Vanete; Rakshit, Sudip Kumar; Pagnoncelli, Maria Giovana Binder; Vandenberghe, Luciana Porto de Souza; Soccol, Carlos Ricardo

    2017-09-01

    Sugary kefir beverage is produce by fermenting raw sugar solution with kefir grains, the latter consisting of polysaccharide and microorganisms. This beverage, with great consumption in countries such as USA, Japan, France, and Brazil, represents a promising market to functional cultured drinks. This paper reviews the microbial diversity and interaction, kinetics, safety, and bioactivities of sugary kefir fermentation. The literature reviewed here demonstrates that sugary kefir possesses a similar microbial association relative to traditional milk kefir fermentation, especially among lactic acid bacteria and yeast species, such as Lactobacillus, Leuconostoc, Kluyveromyces, Pichia, and Saccharomyces. However, a selective pressure at species level is generally observed, as, for example, the stimulation of Saccharomyces species metabolism, leading to a high content of alcohol in the final product. This also seems to stimulate the growth of acetic acid bacteria that benefit of increased ethanol production to acetic acid metabolism. Existing reports have suggested important bioactivities associated with sugary kefir beverage consumption, such as antimicrobial, antiedematogenic, anti-inflammatory, antioxidant, cicatrizing, and healing activities. Other alternative non-dairy substrates, such as fruits, vegetables, and molasses, have also been tested for adaptation of kefir grains and production of functional beverages with distinct sensory characteristics. This diversification is of crucial importance for the production of new probiotic products to provide people with special needs (lactose intolerance) and vegan consumers. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Chronic administration of the soluble, nonbacterial fraction of kefir attenuates lipid deposition in LDLr-/-mice.

    Science.gov (United States)

    Santanna, Adriélly F; Filete, Placielle F; Lima, Ewelyne M; Porto, Marcella L; Meyrelles, Silvana S; Vasquez, Elisardo C; Endringer, Denise C; Lenz, Dominik; Abdalla, Dulcineia S P; Pereira, Thiago M C; Andrade, Tadeu U

    2017-03-01

    Kefir is obtained by the action of acidic bacteria and yeasts that exist in symbiotic association in kefir grains. Recently, this fermented milk drink has been recommended for the treatment of several clinical conditions, such as inflammatory, gastrointestinal, or cardiovascular-related diseases, or a combination of these diseases. However, its effects on atherosclerosis are not yet clear. The aim of this study was to prove that chronic treatment with a soluble, nonbacterial fraction of kefir could reduce the progression of atherosclerosis in low-density lipoprotein receptor-deficient (LDLr -/- ) mice. LDLr -/- mice were divided into four groups as follows: RESULTS: The soluble, nonbacterial fraction of kefir reduced lipid deposition (P kefir was capable of diminishing the circulating proinflammatory intereukin (IL)-6 level and the ratio of tumor necrosis factor-α to IL-10 (50% and 42%, P kefir was able to decrease the lipid deposition in LDLr -/- hypercholesteremic mice, at least in part through modifying the circulating cytokine profile. The beneficial effects of kefir provide new perspectives for its use as an adjuvant in the prevention of atherosclerosis. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Studies of natural convection heat transfer in dry spent fuel storage casks using the cobra-SFS thermal-hydraulic computer code

    Energy Technology Data Exchange (ETDEWEB)

    Michener, T. [Pacific Northwest National Laboratory, Richland WA (United States); Guttmann, J.; Bajwa, C. [United States Nuclear Regulatory Commission, One White Flin North, Rockville MD (United States)

    2001-07-01

    The purpose of this study is to identify the importance of natural convection cooling within a nuclear dry spent fuel storage system. In the past, applicants submitting requests to the United States Nuclear Regulatory Commission (USNRC) for a license for a dry spent fuel storage system design did not rigorously treat natural convection within the fuel package of the dry storage system. Typically, the applicant applies heat transfer correlations that raise the thermal conductivity of the materials (gas and solid structures) to account for the impact of convection on the thermal performance of the system. (author)

  15. Stability Emulsion and Sensory Characteristics Low Fat Mayonnaise Using Kefir as Emulsifier Replacer

    Directory of Open Access Journals (Sweden)

    Herly Evanuarini

    2017-03-01

    Full Text Available Mayonnaise is a kind of semi solid oil in water (o/w emulsion which containing pasteurized egg yolk as an emulsifier. The consumers have demanded that the use of egg yolk be reduced. Kefir was used to develop a low fat mayonnaise as emulsifier replacer to egg yolk. The objective of this research was to observe the emulsion stability, sensory characteristics of low fat mayonnaise prepare during kefir as emulsifier replacer. The research method was using experimental design. The result showed that formulation of low fat mayonnaise by using Rice bran oil 40%, kefir 20% produces the optimal low fat mayonnaise in emulsion stability and accepted by the panelist.

  16. Kefir improves bone mass and microarchitecture in an ovariectomized rat model of postmenopausal osteoporosis.

    Science.gov (United States)

    Chen, H-L; Tung, Y-T; Chuang, C-H; Tu, M-Y; Tsai, T-C; Chang, S-Y; Chen, C-M

    2015-02-01

    Kefir treatment in ovariectomized (OVX) rats could significantly decrease the levels of bone turnover markers and prevent OVX-induced bone loss, deterioration of trabecular microarchitecture, and biomechanical dysfunction that may be due to increase intracellular calcium uptake through the TRPV6 calcium channel. Osteoporosis is a disease characterized by low bone mass and structural deterioration of bone tissue, leading to an increased fracture risk. The incidence of osteoporosis increases with age and occurs most frequently in postmenopausal women due to estrogen deficiency, as the balance between bone resorption and bone formation shifts towards increased levels of bone resorption. Among various methods of prevention and treatment for osteoporosis, an increase in calcium intake is the most commonly recommended preventive measure. Kefir is a fermented milk product made with kefir grains that degrade milk proteins into various peptides with health-promoting effects, including immunomodulating-, antithrombotic-, antimicrobial-, and calcium-absorption-enhancing bioactivities. The aim of this study is to investigate the effect of kefir on osteoporosis prophylaxis in an ovariectomized rat model. A total of 56 16-week-old female Sprague-Dawley (SD) rats were divided into 7 experimental groups: sham (normal), OVX/Mock, OVX/1X kefir (164 mg/kg BW/day), OVX/2X kefir (328 mg/kg BW/day), OVX/4X kefir (656 mg/kg BW/day), OVX/ALN (2.5 mg/kg BW/day), and OVX/REBONE (800 mg/kg BW/day). After 12-week treatment with kefir, the bone physiology in the OVX rat model was investigated. Accordingly, the aim of this study was to investigate the possible transport mechanism involved in calcium absorption using the Caco-2 human cell line. A 12-week treatment with kefir on the OVX-induced osteoporosis model reduced the levels of C-terminal telopeptides of type I collagen (CTx), bone turnover markers, and trabecular separation (Tb. Sp.). Additionally, treatment with kefir increased

  17. Kefir induces cell-cycle arrest and apoptosis in HTLV-1-negative malignant T-lymphocytes.

    Science.gov (United States)

    Maalouf, Katia; Baydoun, Elias; Rizk, Sandra

    2011-02-14

    Adult lymphoblastic leukemia (ALL) is a malignancy that occurs in white blood cells. The overall cure rate in children is 85%, whereas it is only 40% in adults. Kefir is an important probiotic that contains many bioactive ingredients, which give it unique health benefits. It has been shown to control several cellular types of cancer. The present study investigates the effect of a cell-free fraction of kefir on CEM and Jurkat cells, which are human T-lymphotropic virus type I (HTLV-1)-negative malignant T-lymphocytes. Cells were incubated with different kefir concentrations. The cytotoxicity of the compound was evaluated by determining the percentage viability of cells. The effect of all the noncytotoxic concentrations of kefir on the proliferation of CEM and Jurkat cells was then assessed. The levels of transforming growth factor-alpha (TGF-α), transforming growth factor- beta1 (TGF-β1), matrix metalloproteinase-2 (MMP-2), and MMP-9 mRNA upon kefir treatment were then analyzed using reverse transcriptase polymerase chain reaction (RT-PCR). Finally, the growth inhibitory effects of kefir on cell-cycle progression/apoptosis were assessed by Cell Death Detection (ELISA) and flow cytometry. The maximum cytotoxicity recorded after 48-hours treatment with 80 μg/μL kefir was only 42% and 39% in CEM and Jurkat cells, respectively. The percent reduction in proliferation was very significant, and was dose-, and time-dependent. In both cell lines, kefir exhibited its antiproliferative effect by downregulating TGF-α and upregulating TGF-β1 mRNA expression. Upon kefir treatment, a marked increase in cell-cycle distribution was noted in the preG(1) phase of CEM and Jurkat cells, indicating the proapoptotic effect of kefir, which was further confirmed by Cell Death Detection ELISA. However, kefir did not affect the mRNA expression of metalloproteinases needed for the invasion of leukemic cell lines. In conclusion, kefir is effective in inhibiting proliferation and inducing

  18. Kefir induces cell-cycle arrest and apoptosis in HTLV-1-negative malignant T-lymphocytes

    Science.gov (United States)

    Maalouf, Katia; Baydoun, Elias; Rizk, Sandra

    2011-01-01

    Background: Adult lymphoblastic leukemia (ALL) is a malignancy that occurs in white blood cells. The overall cure rate in children is 85%, whereas it is only 40% in adults. Kefir is an important probiotic that contains many bioactive ingredients, which give it unique health benefits. It has been shown to control several cellular types of cancer. Purpose: The present study investigates the effect of a cell-free fraction of kefir on CEM and Jurkat cells, which are human T-lymphotropic virus type I (HTLV-1)-negative malignant T-lymphocytes. Methods: Cells were incubated with different kefir concentrations. The cytotoxicity of the compound was evaluated by determining the percentage viability of cells. The effect of all the noncytotoxic concentrations of kefir on the proliferation of CEM and Jurkat cells was then assessed. The levels of transforming growth factor-alpha (TGF-α), transforming growth factor- beta1 (TGF-β1), matrix metalloproteinase-2 (MMP-2), and MMP-9 mRNA upon kefir treatment were then analyzed using reverse transcriptase polymerase chain reaction (RT-PCR). Finally, the growth inhibitory effects of kefir on cell-cycle progression/apoptosis were assessed by Cell Death Detection (ELISA) and flow cytometry. Results: The maximum cytotoxicity recorded after 48-hours treatment with 80 μg/μL kefir was only 42% and 39% in CEM and Jurkat cells, respectively. The percent reduction in proliferation was very significant, and was dose-, and time-dependent. In both cell lines, kefir exhibited its antiproliferative effect by downregulating TGF-α and upregulating TGF-β1 mRNA expression. Upon kefir treatment, a marked increase in cell-cycle distribution was noted in the preG1 phase of CEM and Jurkat cells, indicating the proapoptotic effect of kefir, which was further confirmed by Cell Death Detection ELISA. However, kefir did not affect the mRNA expression of metalloproteinases needed for the invasion of leukemic cell lines. Conclusion: In conclusion, kefir is

  19. Kefir induces cell-cycle arrest and apoptosis in HTLV-1-negative malignant T-lymphocytes

    International Nuclear Information System (INIS)

    Maalouf, Katia; Baydoun, Elias; Rizk, Sandra

    2011-01-01

    Adult lymphoblastic leukemia (ALL) is a malignancy that occurs in white blood cells. The overall cure rate in children is 85%, whereas it is only 40% in adults. Kefir is an important probiotic that contains many bioactive ingredients, which give it unique health benefits. It has been shown to control several cellular types of cancer. The present study investigates the effect of a cell-free fraction of kefir on CEM and Jurkat cells, which are human T-lymphotropic virus type I (HTLV-1)-negative malignant T-lymphocytes. Cells were incubated with different kefir concentrations. The cytotoxicity of the compound was evaluated by determining the percentage viability of cells. The effect of all the noncytotoxic concentrations of kefir on the proliferation of CEM and Jurkat cells was then assessed. The levels of transforming growth factor-alpha (TGF-α), transforming growth factor- beta1 (TGF-β1), matrix metalloproteinase-2 (MMP-2), and MMP-9 mRNA upon kefir treatment were then analyzed using reverse transcriptase polymerase chain reaction (RT-PCR). Finally, the growth inhibitory effects of kefir on cell-cycle progression/apoptosis were assessed by Cell Death Detection (ELISA) and flow cytometry. The maximum cytotoxicity recorded after 48-hours treatment with 80 μg/μL kefir was only 42% and 39% in CEM and Jurkat cells, respectively. The percent reduction in proliferation was very significant, and was dose-, and time-dependent. In both cell lines, kefir exhibited its antiproliferative effect by downregulating TGF-α and upregulating TGF-β1 mRNA expression. Upon kefir treatment, a marked increase in cell-cycle distribution was noted in the preG 1 phase of CEM and Jurkat cells, indicating the proapoptotic effect of kefir, which was further confirmed by Cell Death Detection ELISA. However, kefir did not affect the mRNA expression of metalloproteinases needed for the invasion of leukemic cell lines. In conclusion, kefir is effective in inhibiting proliferation and inducing

  20. Oxidation kinetics of Si and SiGe by dry rapid thermal oxidation, in-situ steam generation oxidation and dry furnace oxidation

    Science.gov (United States)

    Rozé, Fabien; Gourhant, Olivier; Blanquet, Elisabeth; Bertin, François; Juhel, Marc; Abbate, Francesco; Pribat, Clément; Duru, Romain

    2017-06-01

    The fabrication of ultrathin compressively strained SiGe-On-Insulator layers by the condensation technique is likely a key milestone towards low-power and high performances FD-SOI logic devices. However, the SiGe condensation technique still requires challenges to be solved for an optimized use in an industrial environment. SiGe oxidation kinetics, upon which the condensation technique is founded, has still not reached a consensus in spite of various studies which gave insights into the matter. This paper aims to bridge the gaps between these studies by covering various oxidation processes relevant to today's technological needs with a new and quantitative analysis methodology. We thus address oxidation kinetics of SiGe with three Ge concentrations (0%, 10%, and 30%) by means of dry rapid thermal oxidation, in-situ steam generation oxidation, and dry furnace oxidation. Oxide thicknesses in the 50 Å to 150 Å range grown with oxidation temperatures between 850 and 1100 °C were targeted. The present work shows first that for all investigated processes, oxidation follows a parabolic regime even for thin oxides, which indicates a diffusion-limited oxidation regime. We also observe that, for all investigated processes, the SiGe oxidation rate is systematically higher than that of Si. The amplitude of the variation of oxidation kinetics of SiGe with respect to Si is found to be strongly dependent on the process type. Second, a new quantitative analysis methodology of oxidation kinetics is introduced. This methodology allows us to highlight the dependence of oxidation kinetics on the Ge concentration at the oxidation interface, which is modulated by the pile-up mechanism. Our results show that the oxidation rate increases with the Ge concentration at the oxidation interface.

  1. Rheological, texture and sensory properties of kefir from mare’s milk and its mixtures with goat and sheep milk

    Directory of Open Access Journals (Sweden)

    Dorota Cais-Sokolińska

    2016-11-01

    Full Text Available The aim of this study was to conduct lactic acid-alcoholic fermentation using mesophilic lactic acid bacteria (LAB for mare’s milk and its mixture with goat and sheep milk, followed by instrumental and sensory characteristic of the texture profile in the produced kefirs. It was shown that kefirs made from a mixture of goat and sheep milk are firmer, have greater values of consistency and the viscosity index than those produced from mare’s milk alone. Kefir storage for 3 weeks causes changes in their mechanical properties. Exceptions are found for firmness of kefirs made from both mixtures and the viscosity index of kefir made from sheep milk, which remained stable. The most divergent texture profile of the tested kefirs was reflected in the sensory examined descriptors of prickling, dense and mouth-coating sensation.

  2. Coupled fluid-thermal analysis of low-pressure sublimation and condensation with application to freeze-drying

    Science.gov (United States)

    Ganguly, Arnab

    Freeze-drying is a low-pressure, low-temperature condensation pumping process widely used in the manufacture of bio-pharmaceuticals for removal of solvents by sublimation. The goal of the process is to provide a stable dosage form by removing the solvent in such a way that the sensitive molecular structure of the active substance is least disturbed. The vacuum environment presents unique challenges for understanding and controlling heat and mass transfer in the process. As a result, the design of equipment and associated processes has been largely empirical, slow and inefficient. A comprehensive simulation framework to predict both, process and equipment performance is critical to improve current practice. A part of the dissertation is aimed at performing coupled fluid-thermal analysis of low-pressure sublimation-condensation processes typical of freeze-drying technologies. Both, experimental and computational models are used to first understand the key heat transfer modes during the process. A modeling and computational framework, validated with experiments for analysis of sublimation, water-vapor flow and condensation in application to pharmaceutical freeze-drying is developed. Augmented with computational fluid dynamics modeling, the simulation framework presented here allows to predict for the first time, dynamic product/process conditions taking into consideration specifics of equipment design. Moreover, by applying the modeling framework to process design based on a design-space approach, it has demonstrated that there is a viable alternative to empiricism.

  3. Multi-material classification of dry recyclables from municipal solid waste based on thermal imaging.

    Science.gov (United States)

    Gundupalli, Sathish Paulraj; Hait, Subrata; Thakur, Atul

    2017-12-01

    There has been a significant rise in municipal solid waste (MSW) generation in the last few decades due to rapid urbanization and industrialization. Due to the lack of source segregation practice, a need for automated segregation of recyclables from MSW exists in the developing countries. This paper reports a thermal imaging based system for classifying useful recyclables from simulated MSW sample. Experimental results have demonstrated the possibility to use thermal imaging technique for classification and a robotic system for sorting of recyclables in a single process step. The reported classification system yields an accuracy in the range of 85-96% and is comparable with the existing single-material recyclable classification techniques. We believe that the reported thermal imaging based system can emerge as a viable and inexpensive large-scale classification-cum-sorting technology in recycling plants for processing MSW in developing countries. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Short communication: The effects of frozen storage on the survival of probiotic microorganisms found in traditionally and commercially manufactured kefir.

    Science.gov (United States)

    O'Brien, K V; Aryana, K J; Prinyawiwatkul, W; Ordonez, K M Carabante; Boeneke, C A

    2016-09-01

    Kefir is a fermented milk traditionally made from a unique starter culture, which consists of numerous bacteria and yeast species bound together in an exopolysaccharide matrix produced by certain lactic acid bacteria. Many health benefits are associated with traditionally produced kefir; however, bulging and leaking packaging, caused by secondary yeast fermentation during storage, has limited large-scale manufacture. Commercial kefir products have been designed to reduce these effects by using a pure starter culture consisting of a mixture of bacteria and yeast species that give a flavor similar to traditional kefir, but some health benefits may be lost in commercial production due to reduced microbial diversity and lack of beneficial exopolysaccharides. In this study, traditional and commercial kefir was frozen to study the effects of frozen storage on the viability of probiotic bacteria over time. Traditional kefir was prepared by inoculating 1L of pasteurized whole goat milk with approximately 30g of kefir grains. Commercial kefir was prepared by inoculating 1L of full-fat, pasteurized goat milk with a commercial kefir starter. The milk was allowed to ferment at room temperature (24-28°C) until pH 4.6 was reached. Samples were frozen (-8 to -14°C) immediately following the completion of fermentation and were thawed and plated for lactobacilli, lactococci, and yeasts on d 0, 7, 14, and 30 of frozen storage. Lactobacilli, lactococci, and yeasts were significantly reduced in number during frozen storage; however, the traditionally produced kefir was shown to have significantly higher counts of bacteria and yeast at each sampling. We concluded that frozen storage and the development of frozen kefir products could eliminate most packaging concerns associated with the large-scale manufacture of traditionally produced kefir, resulting in increased production and marketability of this healthful product. Copyright © 2016 American Dairy Science Association. Published

  5. Lactic Acid Bacteria from Kefir Increase Cytotoxicity of Natural Killer Cells to Tumor Cells.

    Science.gov (United States)

    Yamane, Takuya; Sakamoto, Tatsuji; Nakagaki, Takenori; Nakano, Yoshihisa

    2018-03-27

    The Japanese fermented beverage, homemade kefir, contains six lactic acid bacteria: Lactococcus. lactis subsp. Lactis , Lactococcus . lactis subsp. Cremoris , Lactococcus. Lactis subsp. Lactis biovar diacetylactis , Lactobacillus plantarum , Leuconostoc meseuteroides subsp. Cremoris and Lactobacillus casei . In this study, we found that a mixture of the six lactic acid bacteria from kefir increased the cytotoxicity of human natural killer KHYG-1 cells to human chronic myelogenous leukemia K562 cells and colorectal tumor HCT116 cells. Furthermore, levels of mRNA expression and secretion of IFN-γ (interferon gamma) increased in KHYG-1 cells that had been treated with the six lactic acid bacteria mixture from kefir. The results suggest that the six lactic acid bacteria mixture from kefir has strong effects on natural immunity and tumor cell cytotoxicity.

  6. Pengaruh Jenis Susu dan Persentase Starter yang Berbeda terhadap Kualitas Kefir

    Directory of Open Access Journals (Sweden)

    Yusdar Zakaria

    2009-04-01

    Full Text Available Effect of different milk and starter percentage on kefir quality ABSTRACT. The objective of this study is to study the quality of kefir with different amount of starter added and different kind of milk. The quality of kefir was evaluated by measuring lactic acid level, syneresis, crude protein, crude fat and amount of active microorganism. The result showed that the different percentage of starter and kind of milk has a high significant on syneresis and Lactic Acid level (P < 0,01. The best interaction was resulted from the combination of 10% starter and UHT milk. The result also indicated that the different percentage of starter and kind of milk has no effect on crude protein, crude fat and the amount of active microorganism. The combination of 10% Starter and UHT milk, produces the best quality of kefir

  7. Chronic administration of the probiotic kefir improves the endothelial function in spontaneously hypertensive rats.

    Science.gov (United States)

    Friques, Andreia G F; Arpini, Clarisse M; Kalil, Ieda C; Gava, Agata L; Leal, Marcos A; Porto, Marcella L; Nogueira, Breno V; Dias, Ananda T; Andrade, Tadeu U; Pereira, Thiago Melo C; Meyrelles, Silvana S; Campagnaro, Bianca P; Vasquez, Elisardo C

    2015-12-30

    The beverage obtained by fermentation of milk with kefir grains, a complex matrix containing acid bacteria and yeasts, has been shown to have beneficial effects in various diseases. However, its effects on hypertension and endothelial dysfunction are not yet clear. In this study, we evaluated the effects of kefir on endothelial cells and vascular responsiveness in spontaneously hypertensive rats (SHR). SHR were treated with kefir (0.3 mL/100 g body weight) for 7, 15, 30 and 60 days and compared with non-treated SHR and with normotensive Wistar-Kyoto rats. Vascular endothelial function was evaluated in aortic rings through the relaxation response to acetylcholine (ACh). The balance between reactive oxygen species (ROS) and nitric oxide (NO) synthase was evaluated through specific blockers in the ACh-induced responses and through flow cytometry in vascular tissue. Significant effects of kefir were observed only after treatment for 60 days. The high blood pressure and tachycardia exhibited by the SHR were attenuated by approximately 15 % in the SHR-kefir group. The impaired ACh-induced relaxation of the aortic rings observed in the SHR (37 ± 4 %, compared to the Wistar rats: 74 ± 5 %), was significantly attenuated in the SHR group chronically treated with kefir (52 ± 4 %). The difference in the area under the curve between before and after the NADPH oxidase blockade or NO synthase blockade of aortic rings from SHR were of approximately +90 and -60 %, respectively, when compared with Wistar rats. In the aortic rings from the SHR-kefir group, these values were reduced to +50 and -40 %, respectively. Flow cytometric analysis of aortic endothelial cells revealed increased ROS production and decreased NO bioavailability in the SHR, which were significantly attenuated by the treatment with kefir. Scanning electronic microscopy showed vascular endothelial surface injury in SHR, which was partially protected following administration of kefir for 60 days. In addition, the

  8. Effects of Kefir on the Cardiac Autonomic Tones and Baroreflex Sensitivity in Spontaneously Hypertensive Rats.

    Science.gov (United States)

    Klippel, Brunella F; Duemke, Licia B; Leal, Marcos A; Friques, Andreia G F; Dantas, Eduardo M; Dalvi, Rodolfo F; Gava, Agata L; Pereira, Thiago M C; Andrade, Tadeu U; Meyrelles, Silvana S; Campagnaro, Bianca P; Vasquez, Elisardo C

    2016-01-01

    It has been previously shown that the probiotic kefir (a symbiotic matrix containing acid bacteria and yeasts) attenuated the hypertension and the endothelial dysfunction in spontaneously hypertensive rats (SHR). In the present study, the effect of chronic administration of kefir on the cardiac autonomic control of heart rate (HR) and baroreflex sensitivity (BRS) in SHR was evaluated. SHR were treated with kefir (0.3 mL/100 g body weight) for 60 days and compared with non-treated SHR and with normotensive Wistar-Kyoto rats. Cardiac autonomic vagal (VT) and sympathetic (ST) tones were estimated through the blockade of the cardiac muscarinic receptors (methylatropine) and the blockade of β1-adrenoceptor (atenolol). The BRS was evaluated by the tachycardia and bradycardia responses to vasoactive drug-induced decreases and increases in arterial blood pressure (BP), respectively. Additionally, spontaneous BRS was estimated by autoregressive spectral analysis. Kefir-treated SHR exhibited significant attenuation of basal BP, HR, and cardiac hypertrophy compared to non-treated SHR (12, 13, and 21%, respectively). Cardiac VT and ST were significantly altered in the SHR (~40 and ~90 bpm) compared with Wistar rats (~120 and ~30 bpm) and were partially recovered in SHR-kefir (~90 and ~25 bpm). SHR exhibited an impaired bradycardic BRS (~50%) compared with Wistar rats, which was reduced to ~40% in the kefir-treated SHR and abolished by methylatropine in all groups. SHR also exhibited a significant impairment of the tachycardic BRS (~23%) compared with Wistar rats and this difference was reduced to 8% in the SHR-kefir. Under the action of atenolol the residual reflex tachycardia was smaller in SHR than in Wistar rats and kefir attenuated this abnormality. Spectral analysis revealed increased low frequency components of BP (~3.5-fold) and pulse interval (~2-fold) compared with Wistar rats and these differences were reduced by kefir-treatment to ~1.6- and ~1.5-fold, respectively

  9. Brazilian kefir: structure, microbial communities and chemical composition

    Science.gov (United States)

    Magalhães, Karina Teixeira; de Melo Pereira, Gilberto Vinícius; Campos, Cássia Roberta; Dragone, Giuliano; Schwan, Rosane Freitas

    2011-01-01

    Microbial ecology and chemical composition of Brazilian kefir beverage was performed. The microorganisms associated with Brazilian kefir were investigated using a combination of phenotypic and genotypic methods. A total of 359 microbial isolates were identified. Lactic acid bacteria (60.5%) were the major isolated group identified, followed by yeasts (30.6%) and acetic acid bacteria (8.9%). Lactobacillus paracasei (89 isolates), Lactobacillus parabuchneri (41 isolates), Lactobacillus casei (32 isolates), Lactobacillus kefiri (31 isolates), Lactococcus lactis (24 isolates), Acetobacter lovaniensis (32 isolates), Kluyveromyces lactis (31 isolates), Kazachstania aerobia (23 isolates), Saccharomyces cerevisiae (41 isolates) and Lachancea meyersii (15 isolates) were the microbial species isolated. Scanning electron microscopy showed that the microbiota was dominated by bacilli (short and curved long) cells growing in close association with lemon-shaped yeasts cells. During the 24 h of fermentation, the protein content increased, while lactose and fat content decreased. The concentration of lactic acid ranged from 1.4 to 17.4 mg/ml, and that of acetic acid increased from 2.1 to 2.73 mg/ml. The production of ethanol was limited, reaching a final mean value of 0.5 mg/ml. PMID:24031681

  10. Analog kefir production with a low phenylalanine for Phenylketonuria

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    Amir Yari

    2017-06-01

    Full Text Available Phenylketonuria (PKU is one of the most prevalent types of hereditary metabolic disorders which is caused due to an absence or reduction of the activity of the Phenylalanine hydroxylase enzyme in the liver which in turn, inhibits the transformation of phenylalanine (Phe to tyrosine. In clinical terms, this disorder is displayed with severe, permanent and irreversible mental retardation. This research was aimed at development of a highly nutrient and acceptable suitable analogue Kefir drink for these patients. The mentioned drink is based on milk permeate, cream powder and includes glycomacropeptide (GMP as a source of protein, starter as a fermentation source, the trance glutamines (TG enzyme, dough stabilizer and modified corn starch as tissue maker, salt and water. The GMP used in this analogue drink is intended for enrichment of the product and therefore it was added by 3% to one formula. The aforementioned sample had a lower calculated amount of pH and alcohol percentage in comparison with the 16 samples which did not have GMP. The results of this study showed that the analog kefir has a low level of phenylalanine (30.40 mg/100g and in that regard, it can be considered to be useful for patients with PKU.

  11. Brazilian kefir: structure, microbial communities and chemical composition

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    Karina Teixeira Magalhães

    2011-06-01

    Full Text Available Microbial ecology and chemical composition of Brazilian kefir beverage was performed. The microorganisms associated with Brazilian kefir were investigated using a combination of phenotypic and genotypic methods. A total of 359 microbial isolates were identified. Lactic acid bacteria (60.5% were the major isolated group identified, followed by yeasts (30.6% and acetic acid bacteria (8.9%. Lactobacillus paracasei (89 isolates, Lactobacillus parabuchneri (41 isolates, Lactobacillus casei (32 isolates, Lactobacillus kefiri (31 isolates, Lactococcus lactis (24 isolates, Acetobacter lovaniensis (32 isolates, Kluyveromyces lactis (31 isolates, Kazachstania aerobia (23 isolates, Saccharomyces cerevisiae (41 isolates and Lachancea meyersii (15 isolates were the microbial species isolated. Scanning electron microscopy showed that the microbiota was dominated by bacilli (short and curved long cells growing in close association with lemon-shaped yeasts cells. During the 24 h of fermentation, the protein content increased, while lactose and fat content decreased. The concentration of lactic acid ranged from 1.4 to 17.4 mg/ml, and that of acetic acid increased from 2.1 to 2.73 mg/ml. The production of ethanol was limited, reaching a final mean value of 0.5 mg/ml.

  12. Sequence-based analysis of the microbial composition of water kefir from multiple sources.

    Science.gov (United States)

    Marsh, Alan J; O'Sullivan, Orla; Hill, Colin; Ross, R Paul; Cotter, Paul D

    2013-11-01

    Water kefir is a water-sucrose-based beverage, fermented by a symbiosis of bacteria and yeast to produce a final product that is lightly carbonated, acidic and that has a low alcohol percentage. The microorganisms present in water kefir are introduced via water kefir grains, which consist of a polysaccharide matrix in which the microorganisms are embedded. We aimed to provide a comprehensive sequencing-based analysis of the bacterial population of water kefir beverages and grains, while providing an initial insight into the corresponding fungal population. To facilitate this objective, four water kefirs were sourced from the UK, Canada and the United States. Culture-independent, high-throughput, sequencing-based analyses revealed that the bacterial fraction of each water kefir and grain was dominated by Zymomonas, an ethanol-producing bacterium, which has not previously been detected at such a scale. The other genera detected were representatives of the lactic acid bacteria and acetic acid bacteria. Our analysis of the fungal component established that it was comprised of the genera Dekkera, Hanseniaspora, Saccharomyces, Zygosaccharomyces, Torulaspora and Lachancea. This information will assist in the ultimate identification of the microorganisms responsible for the potentially health-promoting attributes of these beverages. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  13. Characterization of pomegranate juice and whey based novel beverage fermented by kefir grains.

    Science.gov (United States)

    Sabokbar, Nayereh; Khodaiyan, Faramarz

    2015-06-01

    Mixture of pomegranate juice and whey was evaluated as a potential substrate for production of a novel probiotic beverage by kefir grains. Different fermentation conditions were used as viz: two fermentation temperature (19 ºC and 25 ºC) and two levels of kefir grains inoculum (5 % and 8%w/v). pH, acidity, lactose consumption as well as organic acids formation were determined during 32 hours of fermentation. Results showed that kefir grains were able to utilize lactose and decrease pH, increase acidity, produce lactic acid and acetic acid, while the level of citric acid decreased. It was observed these change depended on temperature and level of kefir grains with the highest changes at the temperature of 25 ºC and kefir grains inoculum of 8%w/v. Pomegranate juice and whey mixture therefore may serve as a suitable substrate for the production of novel probiotic dairy-fruit juice beverage by kefir grains and the sensory characteristics of this beverage were shown desirable results.

  14. Kefir protective effects against nicotine cessation-induced anxiety and cognition impairments in rats.

    Science.gov (United States)

    Noori, Negin; Bangash, Mohammad Yasan; Motaghinejad, Majid; Hosseini, Pantea; Noudoost, Behshad

    2014-01-01

    Nicotine as one of the potent psychostimulant drugs is characterized by its parasympathomimetic activity. Upon the abrupt discontinuation of nicotine intake, a number of symptoms such as anxiety, depression and cognition impairment develop. Kefir as a food supplement is rich in tryptophan. In this study, we have evaluated the effects of Kefir on nicotine cessation-induced anxiety, depression and cognition impairment. Forty adult male rats were divided into four groups. All the groups received 6 mg/kg/day of nicotine for 17 days and then the negative control groups got 5 mg/kg/day of normal saline. The positive control groups were given 40 mg/kg/day of Sertraline HCl for 7 days. The group treated with Cow Milk Kefir (CMK) and Soy Milk Kefir (SMK) received 5 mg/kg/day for 7 days. On the 25(th) day, Elevated Plus Maze (EPM), Open Field Test (OFT) and Forced Swim Test (FST) were used to investigate anxiety and depression. In addition, Moris Water Maze was applied to evaluate learning and memory in the animals between the 20(th) and 25(th) days. The results showed that administration of CMK, SMK and Sertraline had higher anti-depression and anxiolytic effects on nicotine withdrawal-induced depression and anxiety in rats (P Kefir had a potential effect on the treatment of nicotine cessation-induced depression, anxiety and cognition impairment in the animal model. Kefir may be useful for adjunct therapy for nicotine abandonment treatment protocols.

  15. Novel technology development through thermal drying of encapsulated Kluyveromyces marxianus in micro- and nano-tubular cellulose in lactose fermentation and its evaluation for food production.

    Science.gov (United States)

    Papapostolou, Harris; Servetas, Yiannis; Bosnea, Loulouda A; Kanellaki, Maria; Koutinas, Athanasios A

    2012-12-01

    A novel technology development based on the production of a low-cost starter culture for ripening of cheeses and baking is reported in the present study. The starter culture comprises thermally dried cells of Kluyveromyces marxianus encapsulated in micro- and nano-tubular cellulose. For production of a low-cost and effective biocatalyst, whey was used as raw material for biomass production and thermal drying methods (convective, conventional, and vacuum) were applied and evaluated at drying temperatures ranging from 35 to 60 °C. The effect of drying temperature of biocatalysts on fermentability of lactose and whey was evaluated. Storage stability and suitability of biocatalysts as a commercial starter cultures was also assessed and evaluated. All thermally dried biocatalysts were found to be active in lactose and whey fermentation. In all cases, there was sugar conversion ranging from 92 to 100 %, ethanol concentration of up to 1.47 % (v/v), and lactic acid concentrations ranged from 4.1 to 5.5 g/l. However, convective drying of the encapsulated cells of K. marxianus in micro- and nano-tubular cellulose was faster and a more effective drying method while drying at 42 °C appear to be the best drying temperature in terms of cell activity, ethanol, and lactic acid formation. Storage of the biocatalysts for 3 months at 4 °C proved maintenance of its activity even though fermentation times increased by 50-100 % compared with the fresh dried ones.

  16. Development of a Dry Inoculation Method for Thermal Challenge Studies in Low-Moisture Foods by Using Talc as a Carrier for Salmonella and a Surrogate (Enterococcus faecium).

    Science.gov (United States)

    Enache, Elena; Kataoka, Ai; Black, D Glenn; Napier, Carla D; Podolak, Richard; Hayman, Melinda M

    2015-06-01

    The objective of this study was to obtain dry inocula of Salmonella Tennessee and Enterococcus faecium, a surrogate for thermal inactivation of Salmonella in low-moisture foods, and to compare their thermal resistance and stability over time in terms of survival. Two methods of cell growth were compared: cells harvested from a lawn on tryptic soy agar (TSA-cells) and from tryptic soy broth (TSB-cells). Concentrated cultures of each organism were inoculated onto talc powder, incubated at 35 °C for 24 h, and dried for additional 24 h at room temperature (23 ± 2 °C) to achieve a final water activity of ≤ 0.55 before sieving. Cell reductions of Salmonella and E. faecium during the drying process were between 0.14 and 0.96 log CFU/g, depending on growth method used. There was no difference between microbial counts at days 1 and 30. Heat resistance of the dry inoculum on talc inoculated into a model peanut paste (50 % fat and 0.6 water activity) was determined after 1 and 30 days of preparation, using thermal death time tests conducted at 85 °C. For Salmonella, there was no significant difference between the thermal resistance (D(85 °C)) for the TSB-cells and TSA-cells (e.g. day 1 cells D(85 °C) = 1.05 and 1.07 min, respectively), and there was no significant difference in D(85 °C) between dry inocula on talc used either 1 or 30 days after preparation (P > 0.05). However, the use the dry inocula of E. faecium yielded different results: the TSB-grown cells had a significantly (P Salmonella Tennessee regardless what cell type was used for dry inoculum preparation; therefore, it proved to be a conservative but appropriate surrogate for thermal inactivation of Salmonella in low-moisture food matrices under the tested conditions.

  17. Non-thermal plasma treatment as a new biotechnology in relation to seeds, dry fruits, and grains

    Science.gov (United States)

    Božena, ŠERÁ; Michal, ŠERÝ

    2018-04-01

    Non-thermal plasma (NTP) technology offers wide potential use in the food technology, the same as in the unconventional agriculture. Some seeds, dry fruits, grains and their sprouts gain popularity in the culinary industry as ‘raw seeds’. This review paper draws the current research and trends in NTP pre-treatment of selected seeds/fruits that are useable as ‘raw seeds’. The main applications are connected with activation of seed germination, early growth of seedlings, microbial inactivation of seed/fruit surface, and possibility of increasing quantity of biological active compounds in sprouting seeds. The paper presents a list of plant species that are able to be used as ‘raw seed’ including current information about main type of NTP treatment implemented.

  18. Measurement of thermal characteristics of spray-dried milk and juice blend.

    Science.gov (United States)

    Afifi, Hanan S; Abu Shelaibi, A A; Laleye, L C; Ismail, I A

    2009-01-01

    Blended concentrated grape/peach (G/P) juice 60% total soluble solids (TSS) with condensed whole cow milk 40% TSS (1.5:8.5) was spray dried using a pilot-scale spray drier FT 80 at feeding pressure 7,000 Pa, at chamber temperature 180 degrees C and at chamber pressure -110 Pa. The glass transition state of blended G/P juice-milk powder, three pure sugars (glucose, sucrose and lactose) and casein were studied using differential scanning calorimetry. The calorimetry showed that G/P juice-milk powder is a glassy material. The glass transition temperature of blended G/P juice-milk powder at 0.248 water activity was 42 degrees C, compared with commercial full milk powder (control) of 29 degrees C at 0.334 at water activity (a(w)).

  19. Understanding the performance and mechanism of Mg-containing oxides as support catalysts in the thermal dry reforming of methane.

    Science.gov (United States)

    Khairudin, Nor Fazila; Sukri, Mohd Farid Fahmi; Khavarian, Mehrnoush; Mohamed, Abdul Rahman

    2018-01-01

    Dry reforming of methane (DRM) is one of the more promising methods for syngas (synthetic gas) production and co-utilization of methane and carbon dioxide, which are the main greenhouse gases. Magnesium is commonly applied in a Ni-based catalyst in DRM to improve catalyst performance and inhibit carbon deposition. The aim of this review is to gain better insight into recent developments on the use of Mg as a support or promoter for DRM catalysts. Its high basicity and high thermal stability make Mg suitable for introduction into the highly endothermic reaction of DRM. The introduction of Mg as a support or promoter for Ni-based catalysts allows for good metal dispersion on the catalyst surface, which consequently facilitates high catalytic activity and low catalyst deactivation. The mechanism of DRM and carbon formation and reduction are reviewed. This work further explores how different constraints, such as the synthesis method, metal loading, pretreatment, and operating conditions, influence the dry reforming reactions and product yields. In this review, different strategies for enhancing catalytic activity and the effect of metal dispersion on Mg-containing oxide catalysts are highlighted.

  20. Selection of lactic acid bacteria from Brazilian kefir grains for potential use as starter or probiotic cultures.

    Science.gov (United States)

    Zanirati, Débora Ferreira; Abatemarco, Mário; Sandes, Sávio Henrique de Cicco; Nicoli, Jacques Robert; Nunes, Álvaro Cantini; Neumann, Elisabeth

    2015-04-01

    Brazilian kefir is a homemade fermented beverage that is obtained by incubating milk or a brown sugar solution with kefir grains that contribute their different microbiological compositions. It is highly important to isolate and characterize microorganisms from Brazilian kefir grains to obtain starter cultures for the industrial production of a standardized commercial kefir. Thus, the present study aimed to isolate lactic acid bacteria from eight kefir grains that were propagated in milk or sugar solutions from five different locations in Brazil and to select Lactobacillus isolates based on desirable in vitro probiotic properties. One hundred eight isolates from both substrates were identified by amplified ribosomal DNA restriction analysis and/or 16S rRNA gene sequencing and were determined to belong to the following 11 species from the genera: Lactococcus, Leuconostoc, Lactobacillus (L.), and Oenococcus. Leuconostoc mesenteroides, Lactobacillus kefiri, and Lactobacillus kefiranofaciens were isolated only from milk grains, whereas Lactobacillus perolens, Lactobacillus parafarraginis, Lactobacillus diolivorans, and Oenococcus oeni were isolated exclusively from sugar water grains. When the microbial compositions of four kefir grains were evaluated with culture-independent analyses, L. kefiranofaciens was observed to predominant in milk grains, whereas Lactobacillus hilgardii was most abundant in sugar water kefir. Unfortunately, L. hilgardii was not isolated from any grain, although this bacteria was detected with a culture-independent methodology. Fifty-two isolated Lactobacilli were tested for gastric juice and bile salt tolerance, antagonism against pathogens, antimicrobial resistance, and surface hydrophobicity. Three Lactobacillus strains (L. kefiranofaciens 8U, L. diolivorans 1Z, and Lactobacillus casei 17U) could be classified as potential probiotics. In conclusion, several lactic acid bacteria that could be used in combination with yeasts as starter

  1. Tuning Thermal Transitions in Dry and Hydrated Polyelectrolyte Layer by Layer Assemblies with Ionic Strength and pH

    Science.gov (United States)

    Vidyasagar, Ajay; Lutkenhaus, Jodie

    2012-02-01

    Layer-by-layer (LbL) assemblies are of significant interest for their potential applications in diverse fields such as energy and drug delivery. However, characterizing their thermal properties has remained a challenge. Here, we present the characterization of dry and of hydrated LbL films containing strong polyelectrolytes poly(diallyldimethylammonium chloride) (PDAC) and poly(styrene sulfonate) PSS) using modulated differential scanning calorimetry (MDSC) and temperature controlled quartz crystal microbalance with dissipation (QCM-D). Our results suggest that hydrated exponentially growing (assembled from 0.25-1.25 M NaCl solutions) PDAC/PSS LbL films have glass transition temperatures (Tg's) between 48-51 ^oC, while linearly growing (assembled from 0 M NaCl) films did not. Other systems explored include poly(allylamine hydrochloride)/poly(acrylic acid)(PAH/PAA) LbL assemblies, which demonstrate linear/exponential growth depending on assembly pH conditions. These results support a standing hypothesis in that linear (or exponential) growth is observed for glassy (or rubbery) LbL films. We have also demonstrated for the first time, thermal transitions in thin PDAC/PSS LbL films using QCM-D by monitoring fluctuations in film hydration and viscoelasticity by probing the film's internal structure as a function of film depth.

  2. KARAKTERISTIK FISIK, KIMIA, MIKROBIOLOGI WHEY KEFIR DAN AKTIVITASNYA TERHADAP PENGHAMBATAN ANGIOTENSIN CONVERTING ENZYME (ACE [Physical, Chemical and Microbiological Characteristics of Whey Kefir and Its Angiotensin Converting Enzyme (ACE Inhibitory Activity

    Directory of Open Access Journals (Sweden)

    Andi Febrisiantosa*

    2013-12-01

    Full Text Available This study was conducted to evaluate the characteristics of whey-based kefir products and their activity to inhibit the angiotensin converting enzyme (ACE. Kefir was produced by using many types of whey, namely SK: skim milk based kefir (control; WK: gouda cheese whey based kefir; and WKB: commercial whey powder based kefir. The experimental design was a completely randomized design. Each treatment was conducted in triplicates. Kefirs were evaluated for physical and chemical properties (pH, total titratable acidity, viscosity, protein, fat, lactose, and alcohol, microbiological (lactic acid bacteria and yeast population, peptide concentration, ACE inhibition, IC50 and Inhibition Efficiency Ratio (IER. The results showed that the types of whey used for kefir productions significantly affected the physical and chemical characteristics of the products (p0.05. The peptide concentration and ACE inhibitory activity of WK, 1.54±0.02 mg/mL and 73.07±0.91%, was significantly higher (p0.05 from the control (47.19±0.09% per mg/mL but was significantly higher (p<0.05 than that of WKB (45.75±0.18% per mg/mL. This research indicated that whey kefir is a potential source of bioactive peptide for antihypertention agent.

  3. Thermal modeling of the Clear Lake magmatic system, California: Implications for conventional and hot dry rock geothermal development

    Energy Technology Data Exchange (ETDEWEB)

    Stimac, J.; Goff, F.; Wohletz, K.

    1997-06-01

    The combination of recent volcanism, high heat flow ({ge} HFU or 167 mW/m{sup 2}), and high conductive geothermal gradient (up to 120{degree} C/km) makes the Clear Lake region of northern California one of the best prospects for hot dry rock (HDR) geothermal development in the US. The lack of permeability in exploration wells and lack of evidence for widespread geothermal reservoirs north of the Collayomi fault zone are not reassuring indications for conventional geothermal development. This report summarizes results of thermal modeling of the Clear Lake magmatic system, and discusses implications for HDR site selection in the region. The thermal models incorporate a wide range of constraints including the distribution and nature of volcanism in time and space, water and gas geochemistry, well data, and geophysical surveys. The nature of upper crustal magma bodies at Clear Lake is inferred from studying sequences of related silicic lavas, which tell a story of multistage mixing of silicic and mafic magma in clusters of small upper crustal chambers. Thermobarometry on metamorphic xenoliths yield temperature and pressure estimates of {approximately}780--900 C and 4--6 kb respectively, indicating that at least a portion of the deep magma system resided at depths from 14 to 21 km (9 to 12 mi). The results of thermal modeling support previous assessments of the high HDR potential of the area, and suggest the possibility that granitic bodies similar to The Geysers felsite may underlie much of the Clear Lake region at depths as little as 3--6 km. This is significant because future HDR reservoirs could potentially be sited in relatively shallow granitoid plutons rather than in structurally complex Franciscan basement rocks.

  4. Antidiabetic Potential of Kefir Combination from Goat Milk and Soy Milk in Rats Induced with Streptozotocin-Nicotinamide.

    Science.gov (United States)

    Nurliyani; Harmayani, Eni; Sunarti

    2015-01-01

    The study aimed to evaluate the effect of kefir combination from goat milk and soy milk on lipid profile, plasma glucose, glutathione peroxidase (GPx) activity and the improvement of pancreatic β-cell in diabetic rats. Male rats were divided into five treatments: normal control, diabetic control, goat milk kefir, combination of goat milk-soy milk kefir and soy milk kefir. All rats were induced by streptooztocin-nicotinamide (STZ-NA), except for normal control. After 35 d experiment, the rats were sampled for blood, sacrificed and sampled for pancreatic tissues. Results showed that diabetic rats fed kefir combination had higher (pkefir. Decreasing of plasma glucose in diabetic rats fed kefir combination was higher (pkefir. The activity of GPx in diabetic rats fed three kinds of kefir were higher (pkefir combination was the same as the normal control, but it was higher than diabetic control. It was concluded that kefir combination can be used as antidiabetic through maintaining in serum triglyceride, decreasing in plasma glucose, increasing in GPx activity and improving in pancreatic β-cells.

  5. Effects of fibre type and kefir, wine lemon, and pineapple marinades on texture and sensory properties of wild boar and deer longissimus muscle.

    Science.gov (United States)

    Żochowska-Kujawska, J; Lachowicz, K; Sobczak, M

    2012-12-01

    Fibre type percentage and changes in textural parameters, sensory properties as well as mean fibre cross sectional area (CSA), fibre shape, endomysium and perimysium thickness of wild boar and deer longissimus (L) muscle subjected to ageing with kefir, dry red wine, lemon and pineapple juice marinades for 4 days were studied. Among the non-marinated and non-aged samples of muscles it was found that wild boar meat with its higher percentage of red fibres, higher CSA, thicker connective tissue as compared with deer meat, was harder, more springy and stringy. Muscles ageing, regardless of methods, resulted in a decrease in both the CSA and thickness of the connective tissue, and improve in fibre shape. As a consequence ageing caused a reduction in hardness, cohesiveness, springiness, and stringiness as well as in augmentation of tenderness, juiciness and general attractiveness of the muscles studied. As demonstrated by obtained data, regardless of ageing methods, deer L muscle contained more white fibres compared to wild boar muscle, were more susceptible to tenderization. The highest structural and textural changes, but the worst general attractiveness was found in muscles marinated with pineapple juice addition. Insignificantly lower changes in both quality traits were found in muscles aged with kefir marinade which at the same time were characterized by the high tenderness, the highest juiciness and general attractiveness. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Protective effects of the fermented milk Kefir on X-ray irradiation-induced intestinal damage in B6C3F1 mice.

    Science.gov (United States)

    Teruya, Kiichiro; Myojin-Maekawa, Yuki; Shimamoto, Fumio; Watanabe, Hiromitsu; Nakamichi, Noboru; Tokumaru, Koichiro; Tokumaru, Sennosuke; Shirahata, Sanetaka

    2013-01-01

    Gastrointestinal damage associated with radiation therapy is currently an inevitable outcome. The protective effect of Kefir was assessed for its usefulness against radiation-induced gastrointestinal damage. A Kefir supernatant was diluted by 2- or 10-fold and administered for 1 week prior to 8 Gray (Gy) X-ray irradiation at a dose rate of 2 Gy/min, with an additional 15 d of administration post-irradiation. The survival rate of control mice with normal drinking water dropped to 70% on days 4 through 9 post-irradiation. On the other hand, 100% of mice in the 10- and 2-fold-diluted Kefir groups survived up to day 9 post-irradiation (pKefir solutions (pKefir solutions protected the crypts from radiation, and promoted crypt regeneration. In addition, lyophilized Kefir powder was found to significantly recover the testis weights (pKefir could be a promising candidate as a radiation-protective agent.

  7. PENGARUH PEMBERIAN KEFIR BENING TERHADAP KADAR GLUKOSA DARAH PADA TIKUS WISTAR HIPERGLIKEMIA YANG DIINDUKSI STREPTOZOTOCIN (STZ

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    Judiono Judiono

    2012-11-01

    Full Text Available ABSTRACT Background: Hyperglycemia in diabetes caused by excessive free-radicals, which in turn increases reactive oxygen species, reduced immune function and antioxidant, the beta cell damage. Objective: To validate the effects of plain kefir probiotic on blood glucose level in streptozotocin (STZ induced hyperglycemia Wistar rats. Methods: The experiment using randomized pretest-posttest control group design was carried-out on 48 male hyperglycemia Wistar rats induced by 40 mg/kg body-weight of STZ. Rats were divided randomly into four groups: (1 negative control fed ad libitum standard diet, (2 positive control induced by STZ, (3 insulin treated 0.76 UI/200 g body weight, and (4 plain kefir 3.6 cc per day. Kefir is prepared by the use of pasteurized skim milk fermented by kefir commercial inoculums. Blood glucose was measured with Super Glucocard II meter (Arkray, Kyoto, Japan. Results Kefir supplementation 3.6 cc per day had significantly effect on blood glucose reduction after… days. Results showed that blood glucose levels before and after the treatment in each group as follows: in negative control group, before and after the treatment were 92.7 ± 6.6 mgdL and 89.4 ± 5.3 mgdL, respectively; in positive control group, before and after treatment were 263.9 ± 61.7 mgdL and 290.9 ± 99.8 mgdL; in insulin group, before and after the treatment were 286.9 ± 73.2 mgdL and 168.3 ± 53.3 mgdL; and in kefir group, before and after the treatment were 234.0 ± 61.1 mgdL and 147.8 ± 52.6 mgdL. Conclusion: Kefir supplementation significantly reduced blood glucose in vivo. Isolation and identification of probiotic involved on biomolecular and to find out the role of specific probiotic originated from kefir in diabetes mellitus are very challenging to be implemented in clinical application. [Penel Gizi Makan 2009, 32(2: 129-136] Key words: probiotic, kefir, diabetes mellitus, hyperglicemia, streptozotocin

  8. Performance of Holstein calves fed whole milk with or without kefir.

    Science.gov (United States)

    Fouladgar, S; Shahraki, A D Foroozandeh; Ghalamkari, G R; Khani, M; Ahmadi, F; Erickson, P S

    2016-10-01

    A growing body of evidence suggests health-promoting effects of kefir consumption on different nonruminant species, leading to the speculation that kefir may act as a probiotic and benefit calf performance and health. Our objectives were to determine effects of feeding kefir on performance and health of calves in the first 70d of life. Thirty 3-d-old female Holstein calves (body weight=38.2±3.1kg) were blocked by initial body weight and assigned randomly to 1 of 3 treatments (1 calf per pen; 10 pens per treatment). Kefir was added to whole milk (vol/vol) at 0:1 (control; KF0), 1:3 (KF1), or 1:1 (KF2) and fed twice per day (0800 and 1600h) from d3 through 45 and then once per day until weaning, which occurred on d50. Pre- and postweaning intake of starter, daily body weight gain, and gain-to-feed ratio exhibited no difference among treatments. Adding kefir to whole milk fed directly to calves had no effect on concentration of blood metabolites collected on d20, 40, and 70. Body length on d50 (weaning) and 70 was greater in kefir-fed calves. Kefir intake improved fecal scores and reduced days with diarrhea during the first 2wk of life. Apparent digestibility of organic matter, ether extract, crude protein, and neutral detergent fiber remained unaffected by treatment. Overall, it appears that directly feeding kefir to calves during the preweaning period did not improve the performance of calves under the conditions of the current study; however, its consumption marginally improved body length and fecal consistency in the first weeks of life, which is an important concern in intensive calf-rearing systems. Feeding kefir to neonatal calves may be a viable approach to improve the health of calves in commercial calf-rearing operations, although to validate its health-promoting effects additional research is needed to investigate its effects under different calf-rearing conditions. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights

  9. Influence of Different Growth Conditions on the Kefir Grains Production, used in the Kefiran Synthesis

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    Carmen Rodica Pop

    2014-11-01

    Full Text Available The purpose of this study was to optimize the kefir grains biomass production, using milk as culture media. The kefir grains were cultured at different changed conditions (temperature, time, shaker rotating speed, culture media supplemented to evaluate their effects. Results showed that optimal culture conditions were using the organic skim milk, incubated at 25°C for 24 hours with a rotation rate of 125 rpm. According to results, the growth rate was 38.9 g/L for 24 h, at 25°C using the organic milk - OSM, 36.87 g/L during 24 hours, optimal time for propagation process gave 37.93 g/L kefir grains biomass when the effect of temperature level was tested. The homogenization of medium with shaker rotating induced a greater growth rate, it was obtained 38.9 g/L for 24 h, at 25°C using rotation rate at 125 rpm. The growing medium (conventional milk supplemented with different minerals and vitamins may lead to improve the growth conditions of kefir grains biomass. The optimization of the growth environment is very important for achieving the maximum production of kefir grains biomass, substrate necessary to obtain the polysaccharide kefiran

  10. Development and characterization of a soymilk Kefir-based functional beverage

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    Camilla Fernanda Godinho da SILVA

    2018-03-01

    Full Text Available Abstract Kefir is a fermented beverage that deserves special attention, since it has probiotic activity and unique sensory, nutritional, and therapeutic properties. Given that both kefir and soymilk are beneficial to human health, this study aimed to assess the physicochemical characteristics and acceptability of soymilk Kefir-based functional beverages (SKB properly inoculated with lactobacilli strain after 16h of incubation at 37 °C. It was monitored lactobacilli cell viability, yeasts count, pH, titratable acidity, lipids, proteins, ash, total solid, carbohydrates, caloric values and acceptability of the products. Additionally was conducted a shelf-life study of SKB added of peach-flavor. The lactobacilli cell count ranged from 7.0 to 8.0 Log10 CFUmL-1 and pH values from 4.5 to 4.6. SKB samples with higher soymilk kefir percent presented higher lactobacilli cell count and lower lipid, ash, total solid, carbohydrate and caloric value. Results showed similar preferential rates for the SKB up to 30% of added soymilk kefir. The functional peach-flavored beverage presented appropriate pH value (4.3 and high viable cells count (7.0 Log10 CFUmL-1 up to the 28th day of cold storage, showed high acceptability (94.5% and positive purchase intention (83.4% among consumers.

  11. Efficacy of Kefir on the Release of Lysosomal Proteases After Expremintal Spinal Cord Trauma

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    Emre Delen

    2015-11-01

    Full Text Available Aim: Prevention of secondary injury developing as a result of spinal cord injury will reduce significantly neurological deficits which may occur after trauma. These are focused in experimental studies and many agents are being tested. In our study, we have invesitigated the effects of kefir, which is a a probiotic, associated with life prolongation, whose antioxidant and lipid peroxidation effects were revealed on despite the scientific studies were limited, on lipid peroxidation and lysosomal proteases which play important roles in spinal cord. Material and Method: In the study, female Sprague Dawley rats weighing 200 to 250 g were used. The study was conducted on five groups with a total of 40 rats including the control, trauma, trauma treatment, trauma treatment kefir and trauma kefir groups. The high-dose methylprednisolone was used as the therapy. Spinal cord trauma was performed with clip compression method at the level of T10. Kefir was given to rats via orogastric ways, prior to trauma for 7 days at a dose of 2 * 1cc/100g. All rats were sacrificed 48 hours after treatment. The changes in the value of tissue cathepsins B and L, MDA and histopathological changes were examined. Results: It has been found in our study according to the review of biochemical values that; kefir did not reduce significantly cathepsin B values compared to the treatment group (p> 0.05, did reduce significantly MDA value compared to treatment group (p

  12. The Neuroprotective Effect of Kefir on Spinal Cord Ischemia/Reperfusion Injury in Rats.

    Science.gov (United States)

    Guven, Mustafa; Akman, Tarik; Yener, Ali Umit; Sehitoglu, Muserref Hilal; Yuksel, Yasemin; Cosar, Murat

    2015-05-01

    The main causes of spinal cord ischemia are a variety of vascular pathologies causing acute arterial occlusions. We investigated neuroprotective effects of kefir on spinal cord ischemia injury in rats. Rats were divided into three groups : 1) sham operated control rats; 2) spinal cord ischemia group fed on a standard diet without kefir pretreatment; and 3) spinal cord ischemia group fed on a standard diet plus kefir. Spinal cord ischemia was performed by the infrarenal aorta cross-clamping model. The spinal cord was removed after the procedure. The biochemical and histopathological changes were observed within the samples. Functional assessment was performed for neurological deficit scores. The kefir group was compared with the ischemia group, a significant decrease in malondialdehyde levels was observed (pkefir group were significantly higher than ischemia group (pkefir group is compared with ischemia group, there was a significant decrease in numbers of dead and degenerated neurons (pkefir group compared with ischemia group (pkefir group were significantly higher than ischemia group at 24 h (pkefir pretreatment in spinal cord ischemia/reperfusion reduced oxidative stress and neuronal degeneration as a neuroprotective agent. Ultrastructural studies are required in order for kefir to be developed as a promising therapeutic agent to be utilized for human spinal cord ischemia in the future.

  13. Identification and Relative Quantification of Bioactive Peptides Sequentially Released during Simulated Gastrointestinal Digestion of Commercial Kefir.

    Science.gov (United States)

    Liu, Yufang; Pischetsrieder, Monika

    2017-03-08

    Health-promoting effects of kefir may be partially caused by bioactive peptides. To evaluate their formation or degradation during gastrointestinal digestion, we monitored changes of the peptide profile in a model of (1) oral, (2) gastric, and (3) small intestinal digestion of kefir. Matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy analyses revealed clearly different profiles between digests 2/3 and kefir/digest 1. Subsequent ultraperformance liquid chromatography-electrospray ionization-tandem mass spectrometry identified 92 peptides in total (25, 25, 43, and 30, partly overlapping in kefir and digests 1, 2, and 3, respectively), including 16 peptides with ascribed bioactivity. Relative quantification in scheduled multiple reaction monitoring mode showed that many bioactive peptides were released by simulated digestion. Most prominently, the concentration of angiotensin-converting enzyme inhibitor β-casein 203-209 increased approximately 10 000-fold after combined oral, gastric, and intestinal digestion. Thus, physiological digestive processes may promote bioactive peptide formation from proteins and oligopeptides in kefir. Furthermore, bioactive peptides present in certain compartments of the gastrointestinal tract may exert local physiological effects.

  14. Water Kefir grain as a source of potent dextran producing lactic acid bacteria

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    Davidović Slađana Z.

    2015-01-01

    Full Text Available Water kefir is abeverage fermented by a microbial consortium captured in kefir grains. The kefir grains matrix is composed of polysaccharide, primarily dextran, whichis produced by members of the microbial consortium. In this study, we have isolated lactic acid bacteria (LAB from non-commercial water kefir grains (from Belgrade, Serbia and screened for dextran production. Among twelve Lisolates threeproduced slime colonies on modified MRS (mMRS agar containing sucrose instead of glucoseand were presumed to produce dextran. Three LABwere identified based on morphological, physiological and biochemical characteristics and 16S rRNA sequencing as Leuconostoc mesenteroides(strains T1 and T3 and Lactobacillus hilgardii (strain T5. The isolated strains were able to synthesize a substantial amount of dextran in mMRS broth containing 5% sucrose. Maximal yields (11.56, 18.00 and 18.46 g/l were obtained after 16h, 20h and 32h for T1, T3 and T5, respectively. Optimal temperature for dextran production was 23oC for two Leuconostoc mesenteroides strains and 30oC for Lactobacillus hilgardii strain. The produced dextrans were identified based on paper chromatography while the main structure characteristics of purified dextranwere observed by FT-IR spectroscopy. Our study shows that water kefir grains are a natural source of potent dextranproducing LAB. [Projekat Ministarstva nauke Republike Srbije, br. TR 31035

  15. Dry Friction Clutch Disc of an Automobile under Transient Thermal Load: A Comparison of Friction Lining Materials

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    Ali Anosh

    2017-01-01

    Full Text Available This paper shows the comparison of temperatures produced in a dry friction clutch disc with different materials during a single engagement to assist in clutch plate design and analysis. A study of usage of different materials for friction lining of clutch disc is required, which will provide improved performance and enhanced life. This investigation is modelled mathematically and solved numerically using finite element method. ANSYS® 15.0 is a dedicated finite element package used for determining the temperature distribution across a clutch disc. In the present work, an investigation of a conventionally used harmful friction lining material asbestos is compared with carbon-carbon composite, S2-glass fibre and aluminium metal matrix composite. The transient thermal analysis of a clutch disc with different materials is performed and the temperature distribution on the clutch system is compared. Simulation results indicate that all the values of the temperature obtained from the analysis of aluminium metal matrix are less than those of asbestos based lining material, therefore clutch disc made up of aluminium metal matrix composite will assure the extended service life and the longer stability due to the fact that the temperature responsible for the wear and tear has been reduced. Furthermore, the slipping time is also considered in this investigation.

  16. Effects of aeration on matrix temperature by infrared thermal imager and computational fluid dynamics during sludge bio-drying.

    Science.gov (United States)

    Yu, Dawei; Yang, Min; Qi, Lu; Liu, Mengmeng; Wang, Yawei; Wei, Yuansong

    2017-10-01

    The effect of aeration on the pile matrix temperature was investigated using thermocouples and Infrared Thermal Imager (IRI) for temperature sensing, and Computational Fluid Dynamics (CFD) for modelling of temperature variation during aeration in a full-scale sludge biodrying plant. With aeration saving of 20%, the improved strategy speeded up biodrying from 21 days to 14 days, while achieving similar drying effect. A persistent thermocouple recorded the one-dimensional (1D) total temperature variation of all aeration strategies. The IRI captured the rapid two-dimensional (2D) pile temperature dropped from 72.5 °C to 30.3 °C during 6 min of aeration, which mechanism suggested as the latent heat of moisture evaporation and sensible heat of air exchange. The CFD three-dimensional (3D) CFD results highlight the importance of latent heat rather than sensible heat. Therefore, the pile temperature drop inferred is ΔT = 5.38 °C theoretically and ΔT = 5.17 ± 4.56 °C practically, per unit of MC removed. These findings also emphasize the possibility of a pile temperature valley, due to excessive aeration under unsaturated vapour conditions. Surface temperature monitored by IRI coupled with 3D temperature simulated by CFD rapidly gives a clear matrix temperature evolution, empowering biodrying by more accurate temperature and aeration. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. [The effect of kefir consumption on human immune system: a cytokine study].

    Science.gov (United States)

    Adiloğlu, Ali Kudret; Gönülateş, Nurettin; Işler, Mehmet; Senol, Altuğ

    2013-04-01

    The systemic effects of bioactive peptides which are produced by the fermentation of milk via the microorganisms found in kefir have been the subject of interest in recent years. Bioactive peptides activate innate immunity by stimulating macrophages, increasing phagocytosis, augmenting NO and cytokine production and boosting the lumen levels of IgG and IgA+ B-lymphocytes. The aim of the present study was to determine the serum cytokine profiles of healthy volunteers after kefir consumption to evaluate helper T (TH) cell polarization and to bring out the effects on native and allergic immune responses. The study was designed as a prospective and self-controlled study. A total of 18 healthy volunteers (age range: 20-40 yrs, mean age: 35.5 ± 7.38 yrs) from a university hospital staff were recruited to the study, with the approval of ethical board and informed consent. The body mass indices of all participants were between normal range (20.10-25.70 kg/m2). After two weeks of a diet free from fermented products, the participants consumed 200 mL kefir daily, for six weeks. Kefir product was prepared by using kefir starter culture (Danisco Biolacta Sp - 05223B 10001, Poland) which contains Lactobacillus spp., Leuconostoc spp., Lactococcus lactis ssp. lactis and Streptococcus termophilus, an overnight incubation at 26°C, and consumed freshly. Fasting blood samples of subjects were collected just before kefir use (0th week), at the end of the 3rd and 6th weeks of kefir consumption, and three weeks after cessation of kefir usage (9th week). Serum TNF-a, IL-1, IL-5, IL-8 and TGF-β levels were measured by using commercial ELISA kits (BioSource, Belgium and Invitrogen, USA). Hemoglobin, serum creatinine and ALT levels of all subjects were also determined for follow-up. All volunteers completed the study period without any problem and declared no complaint. Hemoglobin, creatinine and ALT levels did not change with kefir consumption. Serum IL-8 levels were decreased at 3rd and

  18. Pengaruh suhu dan lama pemeraman pada inkubator terhadap kualitas fisik kefir

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    Herly Evanuarini

    2014-08-01

    Full Text Available The objective of the research was to find out the optimum temperature and ripening duration in incubator to produce kefir which had physical quality that met the standard of fermented milk quality. The method of experiment was factorial randomized block design. The first factor was temperature that consisted of 25oC, 30oC and 35oC. The second factor was ripening duration that consisted of 12 hours, 18 hours and 24 hours. The result showed that the temperature and duration of ripening gave a highly significant effect (P<0.01 on pH and viscosity. The combination of temperature (30oC and ripening duration (24 hours produced kefir which met the standard of Indonesian industry fermented milk such as pH (3.86 and viscosity 157.6 cps. Keywords: Temperature, ripening duration, kefir

  19. Kefir Mikroflorası Üzerinde Araştırma

    OpenAIRE

    Ergüllü, Erol; Üçüncü, Mustafa

    1983-01-01

      Çalışmada, çeşitli yörelerden sağlanmış 7 kefir örneğinin mikroflorası araştırılmış ve elde edilen bulgulara göre, kefir mikroflorasında süt asidi bakterileri (Streptokok ve Laktobasiller) ile mayaların çoğunlukta olduğu belirlenmiştir. Bu bakteri türlerinden her birinin kefir oluşumunda ayrı bir yeri bulunmaktadır. Süt asidi bakterileri sütü pıhtılaştırmakta ve bunlardan bazıları da ayrıca uçucu asitler oluşturarak, kefirin tat ve kokusunun meydana gelmesine katkıda bulunmaktadırlar. Mayal...

  20. Anti-inflammatory and angiogenic activity of polysaccharide extract obtained from Tibetan kefir.

    Science.gov (United States)

    Prado, Maria Rosa Machado; Boller, Christian; Zibetti, Rosiane Guetter Mello; de Souza, Daiany; Pedroso, Luciana Lopes; Soccol, Carlos Ricardo

    2016-11-01

    The search for new bioactive molecules is a driving force for research pharmaceutical industries, especially those molecules obtained from fermentation. The molecules possessing angiogenic and anti-inflammatory attributes have attracted attention and are the focus of this study. Angiogenic activity from kefir polysaccharide extract, via chorioallantoic membrane assay, exhibited a pro-angiogenic effect compared with vascular endothelial factor (pro-angiogenic) and hydrocortisone (anti-angiogenic) activity as standards with an EC50 of 192ng/mL. In terms of anti-inflammatory activity determined via hyaluronidase enzyme assay, kefir polysaccharide extract inhibited the enzyme with a minimal activity of 2.08mg/mL and a maximum activity of 2.57mg/mL. For pharmaceutical purposes, kefir polysaccharide extract is considered to be safe because it does not inhibit VERO cells in cytotoxicity assays. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Kefir Mikroflorası Üzerinde Araştırma

    OpenAIRE

    Ergüllü, Erol; Üçüncü, Mustafa

    2014-01-01

      Çalışmada, çeşitli yörelerden sağlanmış 7 kefir örneğinin mikroflorası araştırılmış ve elde edilen bulgulara göre, kefir mikroflorasında süt asidi bakterileri (Streptokok ve Laktobasiller) ile mayaların çoğunlukta olduğu belirlenmiştir. Bu bakteri türlerinden her birinin kefir oluşumunda ayrı bir yeri bulunmaktadır. Süt asidi bakterileri sütü pıhtılaştırmakta ve bunlardan bazıları da ayrıca uçucu asitler oluşturarak, kefirin tat ve kokusunun meydana gelmesine katkıda bulunmaktadırlar. Mayal...

  2. The Effect of Heating and Postfermentation on Lactoferrin of Fresh and Kefir Goat Milk

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    Erfan Kustiawan

    2012-02-01

    Full Text Available The aim of this study was determinated of lactoferrin profile in goat milk and kefir. The samples were collected from whey raw milk, pasteurized and kefir. Lactoferrin profile in this study consisted of concentration and molecule weight of lactoferrin. Goat lactoferrin was isolated from whey by fractionation on sephadex     G-100 column, it was eluted at 0.1 M phosphate buffer pH 6.8. Characterization of goat lactoferrin by electrophoretic SDS-PAGE techniques detected molecule weight of goat lactoferrin that the isolate of the fractions from fractionation on sephadex G-100 column. Result of the research  showed that pasteurization during storage after fermentation process were influenced by concentration of lactoferrin significant (P<0.05. The molecule weights of lactoferrin in goat milk and kefir were estimated at 84 kDa and 80 kDa. The average concentration of goat lactoferrin at 1.915 mg/ml (without pasteurized, 1.579 mg/ml (pasteurized at 65oC, 0.954 mg/ml (pasteurized at 73oC and 0.322 mg/ml (pasteurized at 83oC. The average concentration of goat lactoferrin in kefir during storage at 0.663 mg/ml (0 day, 0.448 mg/ml (3  day, 0.249 mg/ml (6 day, 0.142 mg/ml (9 day dan 0.048 mg/ml (12 day.  Pasteurization at temperature 65oC 30’’ can defend concentration of lactoferrin higher than temperature 73oC 15’’  and temperature 83oC 2’’. Concentration of lactoferrin in kefir were defended until 12 day storage.   Keywords : Lactoferrin, goat milks, kefir

  3. Comparative study of Kefir yogurt-drink and sodium fluoride mouth rinse on salivary mutans streptococci.

    Science.gov (United States)

    Ghasempour, Maryam; Sefdgar, Seyyed Ali Asghar; Moghadamnia, Ali Akbar; Ghadimi, Reza; Gharekhani, Samane; Shirkhani, Leila

    2014-03-01

    The level of mutans streptococci (MS) is reduced by regularly consumption of probiotic Kefir drink. The present study aiming at answer to this question 'may the Kefir drink be considered an alternative to fluoride rinse?' Twenty-two healthy volunteers aged 22-32 years with good oral hygiene participated in this study. None of participants had received any antibiotic or antimicrobial agent or professional fluoride therapy within the last month. None of them exhibited active caries lesions. Smokers and subjects who have chewing gums xylitol habit or who were undergoing orthodontic treatment were excluded. In a cross over design with 2 parallel groups, people in group A for 2 weeks received 100 ml of Kefir drink per day, then avoided brushing, eating and drinking for an hour. Simultaneously, people in group B were administered 0.05% sodium fluoride rinse in the same manner. After washout period, people in groups A and B respectively used 0.05% sodium fluoride rinse and Kefir drink. Saliva sampling was performed before and after interventions. The acidity and the count of MS were assessed and data were analyzed statistically. There was no significant difference between base line pH values of saliva in study groups (p > 0.05). Although, a significant difference was shown between MS counts before and after interventions (p ≤ 0.0001 and p ≤ 0.0001 for NaF and Kefir respectively), but the equal inhibitory effect was found between study groups (p > 0.05). Kefir drink can inhibit salivary MS as well the sodium fluoride rinse. This beverage may be considered an alternative for fluoride rinse. Clinical significance: Probiotics containing dairy products was known with anticariogenic properties. These agents may be used in caries control strategies adjunctively.

  4. Kefir reduces insulin resistance and inflammatory cytokine expression in an animal model of metabolic syndrome.

    Science.gov (United States)

    Rosa, Damiana D; Grześkowiak, Łukasz M; Ferreira, Célia L L F; Fonseca, Ana Carolina M; Reis, Sandra A; Dias, Mariana M; Siqueira, Nathane P; Silva, Leticia L; Neves, Clóvis A; Oliveira, Leandro L; Machado, Alessandra B F; Peluzio, Maria do Carmo G

    2016-08-10

    There is growing evidence that kefir can be a promising tool in decreasing the risk of many diseases, including metabolic syndrome (MetS). The aim of the present study was to evaluate the effect of kefir supplementation in the diet of Spontaneously Hypertensive Rats (SHR) in which MetS was induced with monosodium glutamate (MSG), and to determine its effect on metabolic parameters, inflammatory and oxidation marker expression and glycemic index control. Thirty animals were used in this experiment. For the induction of MetS, twenty two-day-old male SHR received five consecutive intradermal injections of MSG. For the Negative Control, ten newborn male SHR received intradermal injections of saline solution (0.9% saline solution). After weaning, animals received standard diet and water ad libitum until reaching 3 months old, for the development of MetS. They were then divided into three groups (n = 10): negative control (NC, 1 mL saline solution per day), positive control (PC, 1 mL saline solution per day) and the Kefir group (1 mL kefir per day). Feeding was carried out by gavage for 10 weeks and the animals received standard food and water ad libitum. Obesity, insulin resistance, pro- and anti-inflammatory markers, and the histology of pancreatic and adipose tissues were among the main variables evaluated. Compared to the PC group, kefir supplementation reduced plasma triglycerides, liver lipids, liver triglycerides, insulin resistance, fasting glucose, fasting insulin, thoracic circumference, abdominal circumference, products of lipid oxidation, pro-inflammatory cytokine expression (IL-1β) and increased anti-inflammatory cytokine expression (IL-10). The present findings indicate that kefir has the potential to benefit the management of MetS.

  5. Kefir administration reduced progression of renal injury in STZ-diabetic rats by lowering oxidative stress.

    Science.gov (United States)

    Punaro, Giovana R; Maciel, Fabiane R; Rodrigues, Adelson M; Rogero, Marcelo M; Bogsan, Cristina S B; Oliveira, Marice N; Ihara, Silvia S M; Araujo, Sergio R R; Sanches, Talita R C; Andrade, Lucia C; Higa, Elisa M S

    2014-02-15

    This study aimed at assessing the effects of Kefir, a probiotic fermented milk, on oxidative stress in diabetic animals. The induction of diabetes was achieved in adult male Wistar rats using streptozotocin (STZ). The animals were distributed into four groups as follows: control (CTL); control Kefir (CTLK); diabetic (DM) and diabetic Kefir (DMK). Starting on the 5th day of diabetes, Kefir was administered by daily gavage at a dose of 1.8 mL/day for 8 weeks. Before and after Kefir treatment, the rats were placed in individual metabolic cages to obtain blood and urine samples to evaluate urea, creatinine, proteinuria, nitric oxide (NO), thiobarbituric acid reactive substances (TBARS) and C-reactive protein (CRP). After sacrificing the animals, the renal cortex was removed for histology, oxidative stress and NOS evaluation. When compared to CTL rats, DM rats showed increased levels of glycemia, plasmatic urea, proteinuria, renal NO, superoxide anion, TBARS, and plasmatic CRP; also demonstrated a reduction in urinary urea, creatinine, and NO. However, DMK rats showed a significant improvement in most of these parameters. Despite the lack of differences observed in the expression of endothelial NO synthase (eNOS), the expression of inducible NO synthase (iNOS) was significantly lower in the DMK group when compared to DM rats, as assessed by Western blot analysis. Moreover, the DMK group presented a significant reduction of glycogen accumulation within the renal tubules when compared to the DM group. These results indicate that Kefir treatment may contribute to better control of glycemia and oxidative stress, which is associated with the amelioration of renal function, suggesting its use as a non-pharmacological adjuvant to delay the progression of diabetic complications. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Modelling of aflatoxin G1 reduction by kefir grain using response surface methodology.

    Science.gov (United States)

    Ansari, Farzaneh; Khodaiyan, Faramarz; Rezaei, Karamatollah; Rahmani, Anosheh

    2015-01-01

    Aflatoxin G1 (AFG1) is one of the main toxic contaminants in pistachio nuts and causes potential health hazards. Hence, AFG1 reduction is one of the main concerns in food safety. Kefir-grains contain symbiotic association of microorganisms well known for their aflatoxin decontamination effects. In this study, a central composite design (CCD) using response surface methodology (RSM) was applied to develop a model in order to predict AFG1 reduction in pistachio nuts by kefir-grain (already heated at 70 and 110°C). The independent variables were: toxin concentration (X1: 5, 10, 15, 20 and 25 ng/g), kefir-grain level (X2: 5, 10, 20, 10 and 25%), contact time (X3: 0, 2, 4, 6 and 8 h), and incubation temperature (X4: 20, 30, 40, 50 and 60°C). There was a significant reduction in AFG1 (p kefir-grain used. The variables including X1, X3 and the interactions between X2-X4 as well as X3-X4 have significant effects on AFG1 reduction. The model provided a good prediction of AFG1 reduction under the assay conditions. Optimization was used to enhance the efficiency of kefir-grain on AFG1 reduction. The optimum conditions for the highest AFG1 reduction (96.8%) were predicted by the model as follows: toxin concentration = 20 ng/g, kefir-grain level = 10%, contact time = 6 h, and incubation temperature = 30°C which validated practically in six replications.

  7. Microbial profile of a kefir sample preparations: grains in natura and lyophilized and fermented suspension

    Directory of Open Access Journals (Sweden)

    Rafaela Strada de Oliveira Bergmann

    2010-12-01

    Full Text Available Probiotics are supplementary foods developed by microbial strains that improve animal health beyond basic nutrition. Probiotics are consumed orally, regardless of being considered as normal inhabitants of the intestines, able to survive in enzimatic and biliary secretions. Kefir is a probiotic originated from the old continent, fermented by several bacteria and yeasts, encapsulated in a polyssacharide matrix, and resembles jelly grains. Kefir is also presented as its sourish product both in sugary or milky suspensions containing vitamins, aminoacids, peptides, carbohydrates, ethanol, and volatile compounds. Kefir is known to have a diverse microbial content depending on the country and fermentative substrates, which cause distinct probiotic effects. In this sense, the purpose of this work was to isolate, identify, and quantify the microbial content of a native sugary kefir sample (fermented suspension and lyophilized natural grains. Serial dilutions were plated on Rogosa agar (AR and De Man, Rogosa and Sharpe (MRS, for Lactobacillus; Brain Heart Infusion (BHI, for total bacteria; Sabouraud-Dextrose-Agar (SDA, for yeasts and filamentous fungi; Thioglycolate Agar (TA, for Streptococcus, Acetobacteria and Leuconostoc; and Coconut Water Agar (CWA, and CWA supplemented with yeast extract (CWAY, for various genera. Genera and species for all strains were identified through biochemical reactions and specific API systems. The microbial profile of kefir was different from other sources of grains despite the presence of similar microorganisms and others which have not been reported yet. The data obtained with the CWA and CWAE media suggest that both substrates are alternative and salutary media for culture of kefir strains.

  8. Kefir Peptides Prevent Hyperlipidemia and Obesity in High-Fat-Diet-Induced Obese Rats via Lipid Metabolism Modulation.

    Science.gov (United States)

    Tung, Yu-Tang; Chen, Hsiao-Ling; Wu, Hsin-Shan; Ho, Mei-Hsuan; Chong, Kowit-Yu; Chen, Chuan-Mu

    2018-02-01

    Obesity has reached epidemic proportions worldwide. Obesity is a complex metabolic disorder that is linked to numerous serious health complications with high morbidity. The present study evaluated the effects of kefir peptides on high fat diet (HFD)-induced obesity in rats. Kefir peptides markedly improved obesity, including body weight gain, inflammatory reactions and the formation of adipose tissue fat deposits around the epididymis and kidney, and adipocyte size. Treating high fat diet (HFD)-induced obese rats with kefir peptides significantly reduced the fatty acid synthase protein and increased the p-acetyl-CoA carboxylase protein to block lipogenesis in the livers. Kefir peptides also increased fatty acid oxidation by increasing the protein expressions of phosphorylated AMP-activated protein kinase, peroxisome proliferator-activated receptor-α, and hepatic carnitine palmitoyltransferase-1 in the livers. In addition, administration of kefir peptides significantly decreased the inflammatory response (TNF-α, IL-1β, and TGF-β) to modulate oxidative damage. These results demonstrate that kefir peptides treatment improves obesity via inhibition of lipogenesis, modulation of oxidative damage, and stimulation of lipid oxidation. Therefore, kefir peptides may act as an anti-obesity agent to prevent body fat accumulation and obesity-related metabolic diseases. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. AVALIAÇÃO DA ADIÇÃO DO KEFIR EM DIETA HOSPITALAR

    Directory of Open Access Journals (Sweden)

    Joice de Fátima Laureano Martins

    2012-06-01

    Full Text Available Os grãos de kefir são utilizados na elaboração de um produto lácteo fermentado o qual denominamos kefir. Sua introdução em dietas hospitalares promove vários benefícios aos pacientes e possui grande capacidade de estimular o sistema imunológico. Objetivou-se verificar a aceitação de diferentes formulações tendo como ingrediente o kefir. Os grãos de kefir (5 % foram cultivados por 24 horas à temperatura de 22º C. Em seguida, foram preparadas quatro formulações. Formulação 1 - 50 % de kefir cultivado em leite de vaca integral com 50 % de polpa de morango e adoçante (0,2 mL/100 mL; formulação 2 - 50 % de kefir cultivado em leite de vaca desnatado com 50 % de polpa de morango e adoçante (0,2 mL/100 mL; formulação 3 - 50 % de kefir cultivado em leite de vaca integral com 50 % de polpa de morango e 10 % de sacarose e formulação 4 - 50 % de kefir cultivado em leite de vaca desnatado com 50 % de polpa de morango e 10 % de sacarose. A análise sensorial foi realizada em um hospital do município de Viçosa-MG, tendo como provadores acompanhantes de pacientes internados e funcionários. Verificou-se a aceitação das formulações e utilizouse a escala hedônica de nove pontos. Todas as formulações apresentaram considerável aceitação enquadrando-se com maior frequência entre os escores «gostei moderadamente» a «gostei muito». Estes formulados apresentaram grande potencial para serem introduzidos em dietoterapia e poderão atuar tanto como adjunto ao tratamento de patologias gastrintestinais, como no controle glicêmico e hipercolesterolêmico.

  10. Short communication: Sensory analysis of a kefir product designed for active cancer survivors.

    Science.gov (United States)

    O'Brien, K; Boeneke, C; Prinyawiwatkul, W; Lisano, J; Shackelford, D; Reeves, K; Christensen, M; Hayward, R; Ordonez, K Carabante; Stewart, L K

    2017-06-01

    Kefir is a fermented milk product that is a good source of protein and health-promoting bacteria. It has the potential to improve recovery from exercise and the health and well-being of cancer survivors. The purpose of this study was to explore cancer survivor attitudes about and acceptance of a kefir recovery beverage made from cultured milk, whole fruit, natural sweeteners, and other natural ingredients. Kefir was made by inoculating and fermenting milk with kefir grains. The kefir was then mixed with a fruit base and given to cancer survivors (n = 52) following a bout of exercise. Participants evaluated the acceptability of the beverage samples (overall appearance, aroma, taste, mouthfeel, and overall liking) using a 9-point hedonic scale, and they evaluated the smoothness using a 3-category just-about-right scale (not enough, just about right, and too much). They also expressed their physical and psychological feelings about the beverage using a 5-point scale (1 = not at all to 5 = extremely) and indicated their purchase intent using a binomial (yes/no) response. The health benefits of kefir were then explained, and participants sampled a second beverage (the same product), answering the same questions related to overall liking, feeling, and intent to purchase. We used a paired Student's t-test to compare beverage liking and emotion scores before and after participants learned about the health benefits of kefir. Data are presented as mean ± standard deviations. The beverage scored significantly higher for overall liking after the health benefits were explained (6.5 ± 1.8 and 7.0 ± 1.7 out of 9 before and after the explanation of health benefits, respectively). Participants showed a high intent to purchase before they learned about the health benefits (75% of participants indicated an intent to purchase, and 89% after they learned about the health benefits). The beverage received high scores overall and, except for an improvement in overall liking, we

  11. Microbial Succession and Flavor Production in the Fermented Dairy Beverage Kefir.

    Science.gov (United States)

    Walsh, Aaron M; Crispie, Fiona; Kilcawley, Kieran; O'Sullivan, Orla; O'Sullivan, Maurice G; Claesson, Marcus J; Cotter, Paul D

    2016-01-01

    Kefir is a putatively health-promoting dairy beverage that is produced when a kefir grain, consisting of a consortium of microorganisms, is added to milk to initiate a natural fermentation. Here, a detailed analysis was carried out to determine how the microbial population, gene content, and flavor of three kefirs from distinct geographic locations change over the course of 24-h fermentations. Metagenomic sequencing revealed that Lactobacillus kefiranofaciens was the dominant bacterial species in kefir during early stages of fermentations but that Leuconostoc mesenteroides became more prevalent in later stages. This pattern is consistent with an observation that genes involved in aromatic amino acid biosynthesis were absent from L. kefiranofaciens but were present in L. mesenteroides . Additionally, these shifts in the microbial community structure, and associated pathways, corresponded to changes in the levels of volatile compounds. Specifically, Acetobacter spp. correlated with acetic acid; Lactobacillus spp. correlated with carboxylic acids, esters and ketones; Leuconostoc spp. correlated with acetic acid and 2,3-butanedione; and Saccharomyces spp. correlated with esters. The correlation data suggest a causal relationship between microbial taxa and flavor that is supported by observations that addition of L. kefiranofaciens NCFB 2797 increased the levels of esters and ketones whereas addition of L. mesenteroides 213M0 increased the levels of acetic acid and 2,3-butanedione. Finally, we detected genes associated with probiotic functionalities in the kefir microbiome. Our results illustrate the dynamic nature of kefir fermentations and microbial succession patterns therein and can be applied to optimize the fermentation processes, flavors, and health-related attributes of this and other fermented foods. IMPORTANCE Traditional fermented foods represent relatively low-complexity microbial environments that can be used as model microbial communities to understand

  12. Surface proteins from Lactobacillus kefir antagonize in vitro cytotoxic effect of Clostridium difficile toxins.

    Science.gov (United States)

    Carasi, Paula; Trejo, Fernando M; Pérez, Pablo F; De Antoni, Graciela L; Serradell, María de los Angeles

    2012-02-01

    In this work, the ability of S-layer proteins from kefir-isolated Lactobacillus kefir strains to antagonize the cytophatic effects of toxins from Clostridium difficile (TcdA and TcdB) on eukaryotic cells in vitro was tested by cell detachment assay. S-layer proteins from eight different L. kefir strains were able to inhibit the damage induced by C. difficile spent culture supernatant to Vero cells. Besides, same protective effect was observed by F-actin network staining. S-layer proteins from aggregating L. kefir strains (CIDCA 83115, 8321, 8345 and 8348) showed a higher inhibitory ability than those belonging to non-aggregating ones (CIDCA 83111, 83113, JCM 5818 and ATCC 8007), suggesting that differences in the structure could be related to the ability to antagonize the effect of clostridial toxins. Similar results were obtained using purified TcdA and TcdB. Protective effect was not affected by proteases inhibitors or heat treatment, thus indicating that proteolytic activity is not involved. Only preincubation with specific anti-S-layer antibodies significantly reduced the inhibitory effect of S-layer proteins, suggesting that this could be attributed to a direct interaction between clostridial toxins and L. kefir S-layer protein. Interestingly, the interaction of toxins with S-layer carrying bacteria was observed by dot blot and fluorescence microscopy with specific anti-TcdA or anti-TcdB antibodies, although L. kefir cells did not show protective effects. We hypothesize that the interaction between clostridial toxins and soluble S-layer molecules is different from the interaction with S-layer on the surface of the bacteria thus leading a different ability to antagonize cytotoxic effect. This is the first report showing the ability of S-layer proteins from kefir lactobacilli to antagonize biological effects of bacterial toxins. These results encourage further research on the role of bacterial surface molecules to the probiotic properties of L. kefir and could

  13. Removal of cadmium by Lactobacillus kefir as a protective tool against toxicity.

    Science.gov (United States)

    Gerbino, Esteban; Carasi, Paula; Tymczyszyn, E Elizabeth; Gómez-Zavaglia, Andrea

    2014-08-01

    The aim of this work was to evaluate the capacity of Lactobacillus kefir strains to remove cadmium cations and protect eukaryotic cells from cadmium toxicity. Lb. kefir CIDCA 8348 and JCM 5818 were grown in a 1/2 dilution of MRS broth supplemented with Cd(NO3)2 ranging 0 to 1 mM. Growth kinetics were followed during 76 h at 30 °C by registering optical density at 600 nm every 4-10 h. The accumulated concentration of cadmium was determined on cultures in the stationary phase by atomic absorption. The viability of a human hepatoma cell line (HepG2) upon exposure to (a) free cadmium and (b) cadmium previously incubated with Lb. kefir strains was evaluated by determining the mitochondrial dehydrogenase activity. Lb. kefir strains were able to grow and tolerate concentrations of cadmium cations up to 1 mM. The addition of cadmium to the culture medium increased the lag time in all the concentrations used. However, a decrease of the total biomass (maximum Absorbance) was observed only at concentrations above 0.0012 and 0.0011 mM for strains CIDCA 8348 and JCM 5818, respectively. Shorter and rounder lactobacilli were observed in both strains upon microscopic observations. Moreover, dark precipitates compatible with intracellular precipitation of cadmium were observed in the cytoplasm of both strains. The ability of Lb. kefir to protect eukaryotic cells cultures from cadmium toxicity was analysed using HepG2 cells lines. Concentrations of cadmium greater than 3×10(-3) mM strongly decreased the viability of HepG2 cells. However, when the eukaryotic cells were exposed to cadmium pre-incubated 1 h with Lb. kefir the toxicity of cadmium was considerably lower, Lb. kefir JCM 5818 being more efficient. The high tolerance and binding capacity of Lb. kefir strains to cadmium concentrations largely exceeding the tolerated weekly intake (TWI) of cadmium for food (2.5 μg per kg of body weight) and water (3 μg/l) addressed to human consumption, is an important added value when

  14. The Application Concentration Addition of Skim Milk to Soy Milk Kefir

    OpenAIRE

    Mandang, Filan O; Dien, Henny; Yelnetty, Afriza

    2016-01-01

    Soy milk is a product processed soybean extract that resembles cow's milk. High protein content makes soy milk as highly nutritious vegetable milk. But the beany flavor of the resulting lead soy milk consumption levels are relatively low. One way of improving the quality of soy milk with a probiotic drink that process into soy milk kefir. The purpose of this study to determine the effect of the concentration of skim milk to soy milk kefir quality, namely in terms of the physical and chemical ...

  15. Kefir Grains Change Fatty Acid Profile of Milk during Fermentation and Storage

    OpenAIRE

    Vieira, C. P.; Álvares, T. S.; Gomes, L. S.; Torres, A. G.; Paschoalin, V. M. F.; Conte-Junior, C. A.

    2015-01-01

    Several studies have reported that lactic acid bacteria may increase the production of free fatty acids by lipolysis of milk fat, though no studies have been found in the literature showing the effect of kefir grains on the composition of fatty acids in milk. In this study the influence of kefir grains from different origins [Rio de Janeiro (AR), Viçosa (AV) e Lavras (AD)], different time of storage, and different fat content on the fatty acid content of cow milk after fermentation was invest...

  16. Sequencing-based analysis of the bacterial and fungal composition of kefir grains and milks from multiple sources.

    Science.gov (United States)

    Marsh, Alan J; O'Sullivan, Orla; Hill, Colin; Ross, R Paul; Cotter, Paul D

    2013-01-01

    Kefir is a fermented milk-based beverage to which a number of health-promoting properties have been attributed. The microbes responsible for the fermentation of milk to produce kefir consist of a complex association of bacteria and yeasts, bound within a polysaccharide matrix, known as the kefir grain. The consistency of this microbial population, and that present in the resultant beverage, has been the subject of a number of previous, almost exclusively culture-based, studies which have indicated differences depending on geographical location and culture conditions. However, culture-based identification studies are limited by virtue of only detecting species with the ability to grow on the specific medium used and thus culture-independent, molecular-based techniques offer the potential for a more comprehensive analysis of such communities. Here we describe a detailed investigation of the microbial population, both bacterial and fungal, of kefir, using high-throughput sequencing to analyse 25 kefir milks and associated grains sourced from 8 geographically distinct regions. This is the first occasion that this technology has been employed to investigate the fungal component of these populations or to reveal the microbial composition of such an extensive number of kefir grains or milks. As a result several genera and species not previously identified in kefir were revealed. Our analysis shows that the bacterial populations in kefir are dominated by 2 phyla, the Firmicutes and the Proteobacteria. It was also established that the fungal populations of kefir were dominated by the genera Kazachstania, Kluyveromyces and Naumovozyma, but that a variable sub-dominant population also exists.

  17. Sequencing-based analysis of the bacterial and fungal composition of kefir grains and milks from multiple sources.

    Directory of Open Access Journals (Sweden)

    Alan J Marsh

    Full Text Available Kefir is a fermented milk-based beverage to which a number of health-promoting properties have been attributed. The microbes responsible for the fermentation of milk to produce kefir consist of a complex association of bacteria and yeasts, bound within a polysaccharide matrix, known as the kefir grain. The consistency of this microbial population, and that present in the resultant beverage, has been the subject of a number of previous, almost exclusively culture-based, studies which have indicated differences depending on geographical location and culture conditions. However, culture-based identification studies are limited by virtue of only detecting species with the ability to grow on the specific medium used and thus culture-independent, molecular-based techniques offer the potential for a more comprehensive analysis of such communities. Here we describe a detailed investigation of the microbial population, both bacterial and fungal, of kefir, using high-throughput sequencing to analyse 25 kefir milks and associated grains sourced from 8 geographically distinct regions. This is the first occasion that this technology has been employed to investigate the fungal component of these populations or to reveal the microbial composition of such an extensive number of kefir grains or milks. As a result several genera and species not previously identified in kefir were revealed. Our analysis shows that the bacterial populations in kefir are dominated by 2 phyla, the Firmicutes and the Proteobacteria. It was also established that the fungal populations of kefir were dominated by the genera Kazachstania, Kluyveromyces and Naumovozyma, but that a variable sub-dominant population also exists.

  18. The Effect of Passive Design Strategies on Thermal Performance of Female Secondary School Buildings during Warm Season in Hot Dry Climate

    Directory of Open Access Journals (Sweden)

    Sahar eZahiri

    2016-03-01

    Full Text Available This paper describes a series of field studies and simulation analysis to improve the thermal performance of school buildings in the city of Tehran in Iran during warm season. The field studies used on-site measurement and questionnaire-based survey in the warm spring season in a typical female secondary school building. The on-site monitoring assessed the indoor air temperature and humidity levels of six classrooms while the occupants completed questionnaires covering their thermal sensations and thermal preferences. Moreover, thermal simulation analysis was also carried out to evaluate and improve the thermal performance of the classrooms based on the students’ thermal requirements and passive design strategies. In this study, the environmental design guidelines for female secondary school buildings were introduced for the hot and dry climate of Tehran, using passive design strategies. The study shows that the application of passive design strategies including south and south-east orientation, 10cm thermal insulation in wall and 5cm in the roof, and the combination of 30cm side fins and overhangs as a solar shading devices, as well as all-day ventilation strategy and the use of thermal mass materials with 25cm-30cm thickness, has considerable impact on indoor air temperatures in warm season in Tehran and keeps the indoor environment in an acceptable thermal condition. The results of the field studies also indicated that most of the occupants found their thermal environment not to be comfortable and the simulation results showed that passive design techniques had a significant influence on the indoor air temperature and can keep it in an acceptable range based on the female students’ thermal requirement. Therefore, in order to enhance the indoor environment and to increase the learning performance of the students, it is necessary to use the appropriate passive design strategies, which also reduce the need for mechanical systems and

  19. KEFIRS MANUFACTURED FROM CAMEL (CAMELUS DRAMEDARIUS) MILK AND COW MILK: COMPARISON OF SOME CHEMICAL AND MICROBIAL PROPERTIES

    OpenAIRE

    G. Kavas

    2015-01-01

    This study examined the production possibilities of kefir from fresh camel milk fermented with grain. The findings were then compared with kefir manufactured from cow’s milk. Cow’s milk was fermented with 2.5% grains. The 1% (v/w) glucose enriched camel’s milk was fermented with 10% grains and left in an incubator at 25°C. Physical-chemical and sensorial analyses of the kefir sampleswere measured on day one (18 hours) of storage and microbiological analyses were measured on days one, three an...

  20. Antiobesity Effect of Exopolysaccharides Isolated from Kefir Grains.

    Science.gov (United States)

    Lim, Juha; Kale, Madhuvanti; Kim, Dong-Hyeon; Kim, Hong-Seok; Chon, Jung-Whan; Seo, Kun-Ho; Lee, Hyeon Gyu; Yokoyama, Wallace; Kim, Hyunsook

    2017-11-22

    Physiological properties of water-soluble exopolysaccharides (EPS) and residues after EPS removal (Res) from the probiotic kefir were determined in high-fat (HF) diet-fed C57BL/6J mice. EPS solutions showed rheological properties and lower viscosity compared to those of β-glucan (BG). EPS significantly suppressed the adipogenesis of 3T3-L1 preadipocytes in a dose-dependent manner. Mice were fed HF diets containing 5% EPS, 5% BG, 8% Res, or 5% microcrystalline cellulose (control) for 4 weeks. Compared with the control, EPS supplementation significantly reduced HF diet-induced body weight gain, adipose tissue weight, and plasma very-low-density lipoprotein cholesterol concentration (P < 0.05). Res and BG significantly reduced body weight gain; however, reduction in adipose tissue weight was not statistically significant, suggesting that the antiobesity effect of EPS occurs due to viscosity and an additional factor. EPS supplementation significantly enhanced abundance of Akkermansia spp. in feces. These data indicate that EPS shows significant antiobesity effects possibly via intestinal microbiota alterations.

  1. Kaybolmuş bir İçecek Kefir

    Directory of Open Access Journals (Sweden)

    Zekâi Varnacı

    2015-02-01

    Full Text Available Kafkasya’da bir parça dana veya koyun şirdeni keçi tulumlarında inek sütüyle maserasyona bırakılarak hazırlanır. Süt çabuk ve spontan olarak koagüle olur. Bundan sonra tulum yeniden doldurularak yeni bir işleme geçilir. Birkaç hafta sonra tulumun iç cidarlarında yavaş yavaş süngerimsi bir kabuk tabakası oluşur. İşte bu kabuk tabakası bölünüp veya kasılıp, sonra kurutularak kefir daneleri meydana getirilir. Danelerin görünüşü sarımsı, küçük, tomurcuğumsudur. Bu daneler kefirin hazırlanmasında maya olarak kullanılmak üzere ticarete arzedilir.

  2. In vitro digestibility of goat milk and kefir with a new standardised static digestion method (INFOGEST cost action) and bioactivities of the resultant peptides.

    Science.gov (United States)

    Nehir El, Sedef; Karakaya, Sibel; Simsek, Sebnem; Dupont, Didier; Menfaatli, Esra; Eker, Alper Tolga

    2015-07-01

    The hydrolysis degrees of goat milk and kefir during simulated gastrointestinal digestion and some bioactivities of the resulting peptides after fermentation and digestion were studied. A static in vitro digestion method by the COST FA1005 Action INFOGEST was used and goat milk and kefir were partially hydrolyzed during the gastric phase and had above 80% hydrolysis after duodenal digestion. There were no differences between the digestibility of goat milk and kefir (p > 0.05). Goat milk and kefir displayed about 7-fold antioxidant activity after digestion (p 0.05), however, after in vitro digestion calcium-binding capacity of the goat milk and kefir increased 2 and 5 fold, respectively (p kefir showed a higher dose-dependent inhibitory effect on α-amylase compared to undigested samples (p < 0.05). α-Glucosidase inhibitory activities and in vitro bile acid-binding capacities of the samples were not determined at the studied concentrations.

  3. Identification and assessment of kefir yeast potential for sugar/ethanol-resistance

    Science.gov (United States)

    Miguel, M.G.C.P.; Cardoso, P.G.; Magalhães-Guedes, K.T.; Schwan, R.F.

    2013-01-01

    Biochemical and molecular analysis was used for identification of different kefir yeasts species from Brazil, Canada and the United States of America. The sugar/ethanol-resistant activity of the yeasts was evaluated. Saccharomyces cerevisiae and Kluyveromyces marxianus had the highest growth rates, suggesting biotechnological applications possible for these strains. PMID:24159292

  4. Characterization of lactic acid bacteria from local cow´s milk kefir

    Science.gov (United States)

    Ismail, YS; Yulvizar, C.; Mazhitov, B.

    2018-03-01

    One of products from milk fermentation is kefir. It is made by adding kefir grains which are composed of lactic acid bacteria and yeast into milk. The lactic acid bacteria are a group of bacteria that produce antimicrobial substances and able to inhibit the growth of pathogenic bacteria. In this research, the lactic acid bacteria were isolated from Aceh local cow`s milk kefir to determine the genus of the isolates. The methods used in the characterization of lactic acid bacteria are colony morphology, cell morphology, and biochemical tests which includes a catalase test; 5%, 6.5%, and 10% salt endurance tests; 37°C and 14°C temperature endurance tests, SIM test, TSIA test, MR-VP test, and O/F test. Of the four isolates found from the cow’s milk kefir, two isolates were confirmed as lactic acid bacteria (isolates SK-1 and SK-4). Both isolates are Gram positive bacteria, and have negative catalase activity. From the observations of colony morphology, cell morphology, and biochemical tests, it was found that the genus of SK-1 is Lactobacillus and the genus of SK-4 is Enterococcus.

  5. Labneh with probiotic properties produced from kefir: development and sensory evaluation

    Directory of Open Access Journals (Sweden)

    Daniela Mayumi Usuda Prado Rocha

    2014-12-01

    Full Text Available The labneh or labaneh is a popular fermented milk in the Middle East. Another fermented product that deserves special mention is kefir since it has probiotic activity and unique sensory, nutritional, and therapeutic properties. The aim of the present study was to develop a functional probiotic labneh using kefir as a fermenting agent and to perform a sensory analysis of the obtained product. Kefir was obtained by growing grains in pasteurized milk. Samples of skimmed and whole labneh were prepared from the inoculation of 5% kefir milk (skimmed/whole at 28 ºC for 24h, followed by cooling (12-18h and whey drainage (12-24h, both at 4 ºC. Sensory analysis was performed with 70 untrained panelists using a 9-point scale hedonic in the acceptance tests. The paired t-test was used to compare the differences between the means of the scores obtained, with the significance level of 5%. The labneh prepared showed good acceptance by the judges, and the whole labneh samples had the highest scores in the acceptance test. Further studies on the analysis of microbiological viability, nutritional composition, and determination of shelf life, also to improve acceptability of the low-fat version of the product, are needed.

  6. Evaluation of Kefir as a New Anodic Biocatalyst Consortium for Microbial Fuel Cell.

    Science.gov (United States)

    Silveira, Gustavo; Schneedorf, José Maurício

    2018-02-21

    Kefir, a combined consortium of bacteria and yeast encapsulated by a polymeric matrix of exopolysaccharides, was used as anodic biocatalyst in a two-chamber microbial fuel cell (MFC). Fermentation was followed during 72 h and polarization curves were obtained from linear sweep voltammetry. The effect of methylene blue as charge-transfer mediator in the kefir metabolism was evaluated. UV/Vis spectrophotometry and cyclic voltammetry were applied to evaluate the redox state of the mediator and to characterize the electrochemical activity, whereas current interruption was used for internal resistance determination. Aiming to establish a relationship between the microbial development inside the anodic chamber with the generated power in the MFC, total titratable acidity, pH, viscosity, carbohydrate assimilation, and microbial counting were assayed. The kefir-based MFC demonstrated a maximum power density of 54 mW m -2 after 24 h fermentation, revealing the potential use of kefir as a biocatalyst for microbial fuel cells.

  7. Anti-inflammatory and cicatrizing activities of a carbohydrate fraction isolated from sugary kefir.

    Science.gov (United States)

    Moreira, M E C; Dos Santos, M H; Zolini, G P P; Wouters, A T B; Carvalho, J C T; Schneedorf, J M

    2008-06-01

    Kefir is an association of microrganisms generally grown in milk, with known probiotic activities identified from its soured suspensions. Aqueous media are also able to grow kefir, but little is known about the probiotic properties of its fermented products. This work aimed to evaluate some probiotic properties of a carbohydrate fraction isolated from sugary kefir (sugary kefir carbohydrate [SKC]). Anti-inflammatory activity of the isolated fraction of carbohydrate was tested both in vitro (cellular respirometry and macrophage culture) and in vivo (50% effective dose, rat paw edema, vascular permeability, and cicatrizing test). The results indicated no significant difference for oxygen uptake or macrophage culture between control and test groups. Rat paw edema, however, showed a significant inhibitory activity by 30 +/- 4% and 54 +/- 8% (P < .001) for carrageenan and dextran, respectively. In the cicatrizing test, animals treated with SKC cream also presented less trauma after treatments as compared to the negative control group (P < .05). The overall data suggested the SKC as a natural product that could be used as a constituent of an anti-inflammatory compound.

  8. Ordered mesoporous silica to study the preparation of Ni/Si2 ex nitrate catalysts: impregnation, drying, and thermal treatments

    NARCIS (Netherlands)

    Sietsma, J.R.A.; Meeldijk, J.D.; Versluijs-Helder, M.; Broersma, A.; van Dillen, A.J.; de Jongh, P.E.; de Jong, K.P.

    2008-01-01

    In this contribution, we investigated the preparation of Ni/SiO2 catalysts with aqueous [Ni(OH2)6](NO3)2 solutions via the impregnation and drying method using ordered mesoporous silica SBA-15 (mesopore diameter of 9 nm) as model support to study each step in the preparation: impregnation, drying,

  9. Scalable, "Dip-and-Dry" Fabrication of a Wide-Angle Plasmonic Selective Absorber for High-Efficiency Solar-Thermal Energy Conversion.

    Science.gov (United States)

    Mandal, Jyotirmoy; Wang, Derek; Overvig, Adam C; Shi, Norman N; Paley, Daniel; Zangiabadi, Amirali; Cheng, Qian; Barmak, Katayun; Yu, Nanfang; Yang, Yuan

    2017-11-01

    A galvanic-displacement-reaction-based, room-temperature "dip-and-dry" technique is demonstrated for fabricating selectively solar-absorbing plasmonic-nanoparticle-coated foils (PNFs). The technique, which allows for facile tuning of the PNFs' spectral reflectance to suit different radiative and thermal environments, yields PNFs which exhibit excellent, wide-angle solar absorptance (0.96 at 15°, to 0.97 at 35°, to 0.79 at 80°), and low hemispherical thermal emittance (0.10) without the aid of antireflection coatings. The thermal emittance is on par with those of notable selective solar absorbers (SSAs) in the literature, while the wide-angle solar absorptance surpasses those of previously reported SSAs with comparable optical selectivities. In addition, the PNFs show promising mechanical and thermal stabilities at temperatures of up to 200 °C. Along with the performance of the PNFs, the simplicity, inexpensiveness, and environmental friendliness of the "dip-and-dry" technique makes it an appealing alternative to current methods for fabricating selective solar absorbers. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Total phenolic content and antioxidant activities of pomegranate juice and whey based novel beverage fermented by kefir grains.

    Science.gov (United States)

    Sabokbar, Nayereh; Khodaiyan, Faramarz

    2016-01-01

    Mixture of pomegranate juice and whey was evaluated as a potential substrate for production of a novel beverage by kefir grains. The effects of two different variables, fermentation, temperature (19 and 25 °C) and kefir grain amount (5 %w/v and 8 %w/v), on total phenolic content (TPC) and antioxidant activities of beverage were examined during a fermentation time of 32 h. TPC and antioxidant activities including 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, reducing power, inhibition effect upon linoleic acid autoxidation and inhibition effect upon ascorbate autoxidation increased significantly (p kefir grain amount of 8 %w/v were applied. Results proved antioxidant activities of beverages were desirable and fermentation by kefir grains has the ability to enhance these antioxidant activities, as compared with unfermented beverage. Also pomegranate juice and whey were suitable media for producing a novel dairy-juice beverage.

  11. Therapeutic effect of lyophilized, Kefir-fermented milk on constipation among persons with mental and physical disabilities.

    Science.gov (United States)

    Maki, Rumiko; Matsukawa, Mayumi; Matsuduka, Atsuko; Hashinaga, Masahiko; Anai, Hirofumi; Yamaoka, Yoshio; Hanada, Katsuhiro; Fujii, Chieko

    2017-11-06

    Constipation is a serious problem for persons with mental and physical disabilities in Japan. However, prophylaxis is extremely difficult because the major causes of constipation in these individuals are related to their mental and physical disabilities. Constipation can be successfully treated with glycerol enemas (GEs) and other aperients. As constipation is a lifetime issue for these persons, dietary regimens to prevent constipation can be important. This study evaluated the probiotic effects of kefir-fermented milk for preventing constipation in 42 persons with mental and physical disabilities. The participants were administered 2 g of lyophilized kefir with each meal for 12 weeks and their bowel movements, the administration of GE and other aperients, and stool shape were recorded. The intake of kefir significantly reduced constipation, compared with the baseline status. Some individuals showed complete relief of constipation, whereas others showed no effect. Despite individual variations, consuming kefir daily could prevent constipation. © 2017 Japan Academy of Nursing Science.

  12. Increase of calcium and reduction of lactose concentration in milk by treatment with kefir grains and eggshell.

    Science.gov (United States)

    Fina, Brenda L; Brun, Lucas R; Rigalli, Alfredo

    2016-01-01

    Dairy products are the main source of calcium (Ca), but the loss of the consumption habit contributes to low consumption in adulthood, which leads to osteoporosis and increased fracture risk. Domestic use of kefir is straightforward and the eggshell is a natural discarded source of Ca. This paper proposes the development of an enriched Ca reduced lactose milk using eggshell and kefir. During the in vitro preparation, the pH, Ca and lactose contents were measured. Ca intestinal absorption of untreated milk and milk with kefir was compared. Finally, human volunteers consumed this dairy product and 24-h urine Ca was measured. Results showed that the beverage has lower lactose and higher Ca than untreated milk and milk with kefir. Intestinal Ca absorption was not different between both milks and an increase in urinary Ca excretion was observed in humans. This study provides a methodology to prepare at home a dairy product that could contribute to improve the Ca intake in adults.

  13. Microbiological Characteristic and Nutrition Quality of Goat Milk Kefir Based on Vitamin D3 Fortification Time

    Science.gov (United States)

    Fauziyyah, F.; Panunggal, B.; Afifah, D. N.; Rustanti, N.; Anjani, G.

    2018-02-01

    Goat milk kefir fortified with vitamin D3 is expected to benefit individual with insulin resistance. Different vitamin D3 fortification time allegedly effect microbiological characteristic and nutrition quality of goat milk kefir due to its microbial growth curve, thus this study aimed to analyze those parameters. This study was an experimental research. This study contains five treatments (vitamin D3 fortification at 0, 6, 12, 18, or 24 hours of fermentation) and a group of control. Total lactic acid bacteria, vitamin D3, protein level, fat contain, crude fiber, viscosity, and pH was analyzed by Total Plate Count, spectrophotometry, Bradford method, Babcock method, gravimetric analysis, Ostwald method, and pH meter respectively. Time of vitamin D3 fortification significantly effect vitamin D3 content (p=0,021), fat content (p=0,001), crude fiber (p=0,0001), viscosity (p=0,010), and total lactic acid bacteria (p=0,048). The highest vitamin D3 content was found on the group fortified at 6 hours of fermentation. All treatment groups has lower fat content and crude fiber content than control group. Total LAB in all group meet the Codex standard (≥ 107 CFU/ml). Control group and fortification group at 24 hours of fermentation have higher viscosity than other groups. There was no significant difference found in goat milk kefir protein level (p=0,262) and pH (p=0,056) despite the difference of fortification time. Vitamin D3 fortification time effect vitamin D3 content, fat content, crude fiber, viscosity, and total lactic acid bacteria of goat milk kefir, but did not effect protein content and pH of goat milk kefir.

  14. Evaluation of quality of kefir from milk obtained from goats supplemented with a diet rich in bioactive compounds.

    Science.gov (United States)

    Cais-Sokolińska, Dorota; Pikul, Jan; Wójtowski, Jacek; Danków, Romualda; Teichert, Joanna; Czyżak-Runowska, Grażyna; Bagnicka, Emilia

    2015-04-01

    The composition of bioactive components in dairy products depends on their content in raw milk and the processing conditions. The experimental material consisted of the milk of dairy goats supplemented with 120 g d(-1) per head of false flax cake. The aim of the study was to evaluate the quality of kefir produced from goat's milk with a higher content of bioactive components resulting from supplementation of the goats' diet with false flax cake. The administration of false flax cake to goats had a positive effect on the fatty acid profile of the raw milk, causing an increase in the proportion of polyunsaturated fatty acids (PUFA), including conjugated linoleic acid (CLA) and n-3 fatty acids. Their increased percentage was detected in the kefir after production as well as after storage. The processing value of the harvested milk did not differ from the qualitative characteristics of milk from goats of the control group. Increasing the proportion of bioactive components in goat's milk did not result in changes in the acidity, texture, colour, flavour, aroma or consistency of the kefir obtained. Milk and kefir obtained after the administration of false flax cake to goats contain bioactive components (PUFA including CLA, n-3 and monoenic trans fatty acids) in significant amounts. Kefir from experimental goat's milk did not differ in quality from kefir made from the milk of the control group. © 2014 Society of Chemical Industry.

  15. The effects of postexercise consumption of a kefir beverage on performance and recovery during intensive endurance training.

    Science.gov (United States)

    O'Brien, K V; Stewart, L K; Forney, L A; Aryana, K J; Prinyawiwatkul, W; Boeneke, C A

    2015-11-01

    This study was designed to determine whether kefir accentuates the positive health benefits assessed by measures in fitness, body composition, or both, as a measure of cardiovascular disease risk as well as the biomarker C-reactive protein (CRP). Sixty-seven adult males and females aged 18 to 24 yr were assigned to 1 of 4 groups: (1) endurance training + control beverage, (2) endurance training +kefir beverage,(3) active control + control beverage, or (4) active control + kefir beverage. The exercise groups completed 15 wk of structured endurancetraining while the active control groups maintained their usual exercise routine. Additionally, each group was assigned to either a kefir or a calorie/macronutrient matched placebo beverage that was consumed twice per week. No significant interactions were found among groups with respect to outcome variables with the exception of serum CRP. The endurance training was effective in improving 1.5-mile (2.41 km) times and kefir supplementation may have been a factor in attenuating the increase in CRP that was observed over the course of the intervention period. This preliminary study suggests that kefir may be involved in improving the risk profile for cardiovascular disease as defined by CRP. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  16. Caracterização físico-química e sensorial de kefir tradicional e derivados

    Directory of Open Access Journals (Sweden)

    S. Weschenfelder

    2011-04-01

    Full Text Available Avaliaram-se diferentes populações de grãos de kefir tradicional e de seus derivados, o kefir, o kefir leban e o soro de kefir, quanto às características físico-químicas e sensoriais, quando inoculados em diferentes concentrações de leite padronizado, levando-se em consideração as variáveis tempo/temperatura de incubação, maturação e filtração. A manipulação da população de grãos de kefir foi eficaz na obtenção de produtos com características físico-químicas semelhantes. O volume de leite utilizado na incubação influenciou significativamente as características dos derivados. A avaliação sensorial de antepastos elaborados a partir de kefir leban, condimentados, apresentou boa aceitabilidade.

  17. Kefir fermented milk and kefiran promote growth of Bifidobacterium bifidum PRL2010 and modulate its gene expression.

    Science.gov (United States)

    Serafini, Fausta; Turroni, Francesca; Ruas-Madiedo, Patricia; Lugli, Gabriele Andrea; Milani, Christian; Duranti, Sabrina; Zamboni, Nicole; Bottacini, Francesca; van Sinderen, Douwe; Margolles, Abelardo; Ventura, Marco

    2014-05-16

    Bifidobacteria constitute one of the dominant groups of microorganisms colonizing the human gut of infants. Their ability to utilize various host-derived glycans as well as dietary carbohydrates has received considerable scientific attention. However, very little is known about the role of fermented foods, such as kefir, or their constituent glycans, such as kefiran, as substrates for bifidobacterial growth and for the modulation of the expression of bifidobacterial host-effector molecules. Here, we show that Bifidobacterium bifidum PRL2010 exhibits high growth performance among the bifidobacterial strains tested when cultivated on kefir and/or kefiran polymer. Furthermore, a 16S rRNA metagenomic approach revealed that the microbiota of kefir is modified upon the addition of PRL2010 cells to the kefir matrix. Finally, our results show that kefir and kefiran are able to influence the transcriptome of B. bifidum PRL2010 causing increased transcription of genes involved in the metabolism of dietary glycans as well as genes that act as host-microbe effector molecules such as pili. Altogether, these data support the use of kefir as a valuable means for the delivery of effective microbial cells in probiotic therapy. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Evaluation of kefir as a potential probiotic on growth performance, serum biochemistry and immune responses in broiler chicks

    Directory of Open Access Journals (Sweden)

    Majid Toghyani

    2015-12-01

    Full Text Available This experiment was conducted to evaluate the effect of milk or molasses kefir as a probiotic on growth performance, carcass traits, serum biochemistry and humoral immune responses in broiler chickens. A total of 192 one-d-old as hatched broiler chicks (Ross 308 were randomly allotted to 4 treatments, each with 4 replicate pens of 12 chicks. The following treatments were applied: 1 a basal diet (C and normal drinking water, 2 2% milk kefir in drinking water, 3 2% molasses kefir in drinking water, and 4 the diet C supplemented with commercial probiotic. At d 42, eight birds per treatment were killed for determination of carcass traits. Broilers at 28 days of age were bled for measuring antibody titers against Newcastle disease virus (NDV and avian influenza virus (AIV, at 30 days of age for antibody titers against sheep red blood cell (SRBC, and at 42 days of age for biochemical analysis. Supplementing 2% milk kefir increased body weight of broilers at 28 and 42 days of age (P  0.05 influenced. Broilers supplemented with molasses kefir, had a significantly lower concentration of serum total cholesterol, low density lipoprotein cholesterol and elevated high density lipoprotein cholesterol at 42 days of age (P < 0.05. In conclusion, the results indicated that inclusion of 2% milk kefir in drinking water would improve growth performance of broiler chickens.

  19. Modern perspectives on the health benefits of kefir in next generation sequencing era: Improvement of the host gut microbiota.

    Science.gov (United States)

    Kim, Dong-Hyeon; Jeong, Dana; Kim, Hyunsook; Seo, Kun-Ho

    2018-01-16

    Kefir is a natural complex fermented milk product containing more than 50 species of probiotic bacteria and yeast, and has been demonstrated to have multiple properties conferring health benefits, including antiobesity, anti-hepatic steatosis, antioxidative, antiallergenic, antitumor, anti-inflammatory, cholesterol-lowering, constipation-alleviating, and antimicrobial properties. To better understand the underlying mechanisms of these benefits, we here review research on the effect of kefir (and kefir microorganisms) consumption to modulate the host gut microbiota. Owing to its excellent gastrointestinal resistance and colonization ability and wide ranges of microbial interaction, kefir has shown significant and wide-spectrum modulatory effects on the host gut microbiota. In particular, as a bacteria- and yeast-containing food, kefir can modulate both the gut microbiota and mycobiota. Since the association of this modulation with health benefit has only been addressed in a small number of recent studies thus far, further studies are needed to determine the precise mechanisms of the beneficial effects of kefir in relation to the modulation of the gut microbiota and mycobiota. Gaining this insight will surely help to take full advantage of this unique probiotic food.

  20. Nutrition Quality and Microbiology of Goat Milk Kefir Fortified with Vitamin B12 and Vitamin D3 during Storage

    Science.gov (United States)

    Dianti, EP; Anjani, G.; Afifah, DN; Rustanti, N.; Panunggal, B.

    2018-02-01

    Goat milk kefir fortified vitamin B12 and vitamin D3 can be an alternative to improve insulin resistance. Fortification of vitamin B12 and vitamin D3 could affect the balance of complex ecosystems of bacteria and yeasts in goat milk kefir. We analyzed the nutritional quality and microbiology of goat milk kefir during storage. This experiment was done with completely randomized design consisted of five treatments, ie storage day 0, 3rd, 6th, 9th, and 15th. Vitamin B12, vitamin D3, protein were analyzed using spectrophotometric, fat using babcock method, total lactic acid bacteria using total plate count, pH with pH meter, and viscosity using ostwald method. During 15 days in refrigerated storage, there was no significant difference (p>0,05) of vitamin B12 concentration, protein, fat, and viscosity of kefir. Storage time of the final product caused the decrease of vitamin D3 concentration between day 9 and 15 (p=0,038), pH (p=0,023), and total lactic acid of kefir (p=0,0001). Total lactic acid bacteria increased until 9 days of storage (6161 ± 1.296x107cfu / ml), but decreased to 24% on day 15 (150 ±7.78x107cfu/ml). pH kefir tends to fluctuate during storage with the highest pH value of 4,38 on day-3, and lowest 4.13 on day-9.

  1. Probiotic Properties of Lactobacillus Strains Isolated from Tibetan Kefir Grains

    Science.gov (United States)

    Zheng, Yongchen; Lu, Yingli; Wang, Jinfeng; Yang, Longfei; Pan, Chenyu; Huang, Ying

    2013-01-01

    The objective of this study was to evaluate the functional properties of lactic acid bacteria (LAB) isolated from Tibetan kefir grains. Three Lactobacillus isolates identified as Lactobacillus acidophilus LA15, Lactobacillus plantarum B23 and Lactobacillus kefiri D17 that showed resistance to acid and bile salts were selected for further evaluation of their probiotic properties. The 3 selected strains expressed high in vitro adherence to Caco-2 cells. They were sensitive to gentamicin, erythromycin and chloramphenicol and resistant to vancomycin with MIC values of 26 µg/ml. All 3 strains showed potential bile salt hydrolase (BSH) activity, cholesterol assimilation and cholesterol co-precipitation ability. Additionally, the potential effect of these strains on plasma cholesterol levels was evaluated in Sprague-Dawley (SD) rats. Rats in 4 treatment groups were fed the following experimental diets for 4 weeks: a high-cholesterol diet, a high-cholesterol diet plus LA15, a high-cholesterol diet plus B23 or a high-cholesterol diet plus D17. The total cholesterol, triglyceride and low-density lipoprotein cholesterol levels in the serum were significantly (P<0.05) decreased in the LAB-treated rats compared with rats fed a high-cholesterol diet without LAB supplementation. The high-density lipoprotein cholesterol levels in groups B23 and D17 were significantly (P<0.05) higher than those in the control and LA15 groups. Additionally, both fecal cholesterol and bile acid levels were significantly (P<0.05) increased after LAB administration. Fecal lactobacilli counts were significantly (P<0.05) higher in the LAB treatment groups than in the control groups. Furthermore, the 3 strains were detected in the rat small intestine, colon and feces during the feeding trial. The bacteria levels remained high even after the LAB administration had been stopped for 2 weeks. These results suggest that these strains may be used in the future as probiotic starter cultures for manufacturing

  2. Freeze-Drying From Organic Cosolvent Systems, Part 1: Thermal Analysis of Cosolvent-Based Placebo Formulations in the Frozen State.

    Science.gov (United States)

    Kunz, Claudia; Schuldt-Lieb, Sonja; Gieseler, Henning

    2018-03-01

    The use of cosolvent systems has been demonstrated to shorten lengthy freeze-drying processes and improve the solubility and stability of certain active pharmaceutical ingredients. The goal of the present study was to evaluate the suitability of 2 thermal characterization techniques, differential scanning calorimetry and freeze-dry microscopy, and to identify an optimal cosolvent system. Binary mixtures of a cosolvent (tert-butanol, dimethyl sulfoxide, 1,4-dioxane, acetone, or ethanol) and water were investigated. Ternary mixtures of frequently used excipients (50 mg/g mannitol, sucrose, glycine, or polyvinylpyrrolidone [PVP]) and a solvent-water system were then analyzed for their thermal properties. PVP presented a particularly high glass transition temperature (T g ') in 70% tert-butanol at -17.9°C. Large needle-shaped crystals that have been shown to be associated with improved processability were observed with mannitol and PVP in 40% 1,4-dioxane. A heterogeneous sublimation rate of the solvent and water whose impact on product stability remained unclear was observed with PVP in 40% 1,4-dioxane. Freeze-dry microscopy analysis demonstrated a possible extension of the process time for PVP in 99% dimethyl sulfoxide due to a slowly moving sublimation front. Conceivable negative consequences and the need for special treatment for low-melting cosolvents, such as ethanol and acetone, were predicted and discussed. Copyright © 2018 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  3. Mechanical performance and thermal stability of glass fiber reinforced silica aerogel composites based on co-precursor method by freeze drying

    Science.gov (United States)

    Zhou, Ting; Cheng, Xudong; Pan, Yuelei; Li, Congcong; Gong, Lunlun; Zhang, Heping

    2018-04-01

    In order to maintain the integrity, glass fiber (GF) reinforced silica aerogel composites were synthesized using methltrimethoxysilane (MTMS) and water glass co-precursor by freeze drying method. The composites were characterized by scanning electron microscopy, Brunauer-Emmett-Teller analysis, uniaxial compressive test, three-point bending test, thermal conductivity analysis, contact angle test, TG-DSC analysis. It was found that the molar ratio of MTMS/water glass could significantly affect the properties of composites. The bulk density and thermal conductivity first decreased and then increased with the increasing molar ratio. The composites showed remarkable mechanical strength and flexibility compared with pure silica aerogel. Moreover, when the molar ratio is 1.8, the composites showed high specific surface area (870.9 m2/g), high contact angle (150°), great thermal stability (560 °C) and low thermal conductivity (0.0248 W/m·K). These outstanding properties indicate that GF/aerogels have broad prospects in the field of thermal insulation.

  4. Short communication: Evaluation of the microbiota of kefir samples using metagenetic analysis targeting the 16S and 26S ribosomal DNA fragments.

    Science.gov (United States)

    Korsak, N; Taminiau, B; Leclercq, M; Nezer, C; Crevecoeur, S; Ferauche, C; Detry, E; Delcenserie, V; Daube, G

    2015-06-01

    Milk kefir is produced by fermenting milk in the presence of kefir grains. This beverage has several benefits for human health. The aim of this experiment was to analyze 5 kefir grains (and their products) using a targeted metagenetic approach. Of the 5 kefir grains analyzed, 1 was purchased in a supermarket, 2 were provided by the Ministry of Agriculture (Namur, Belgium), and 2 were provided by individuals. The metagenetic approach targeted the V1-V3 fragment of the 16S ribosomal (r)DNA for the grains and the resulting beverages at 2 levels of grain incorporation (5 and 10%) to identify the bacterial species population. In contrast, the 26S rDNA pyrosequencing was performed only on kefir grains with the aim of assessing the yeast populations. In parallel, pH measurements were performed on the kefir obtained from the kefir grains using 2 incorporation rates. Regarding the bacterial population, 16S pyrosequencing revealed the presence of 20 main bacterial species, with a dominance of the following: Lactobacillus kefiranofaciens, Lactococcus lactis ssp. cremoris, Gluconobacter frateurii, Lactobacillus kefiri, Acetobacter orientalis, and Acetobacter lovaniensis. An important difference was noticed between the kefir samples: kefir grain purchased from a supermarket (sample E) harbored a much higher proportion of several operational taxonomic units of Lactococcus lactis and Leuconostoc mesenteroides. This sample of grain was macroscopically different from the others in terms of size, apparent cohesion of the grains, structure, and texture, probably associated with a lower level of Lactobacillus kefiranofaciens. The kefir (at an incorporation rate of 5%) produced from this sample of grain was characterized by a lower pH value (4.5) than the others. The other 4 samples of kefir (5%) had pH values above 5. Comparing the kefir grain and the kefir, an increase in the population of Gluconobacter in grain sample B was observed. This was also the case for Acetobacter orientalis

  5. Donkey milk kefir induces apoptosis and suppresses proliferation of Ehrlich ascites carcinoma by decreasing iNOS in mice.

    Science.gov (United States)

    Esener, Obb; Balkan, B M; Armutak, E I; Uvez, A; Yildiz, G; Hafizoglu, M; Yilmazer, N; Gurel-Gurevin, E

    2018-04-12

    Donkey milk and donkey milk kefir exhibit antiproliferative, antimutagenic and antibacterial effects. We investigated the effects of donkey milk and donkey milk kefir on oxidative stress, apoptosis and proliferation in Ehrlich ascites carcinoma (EAC) in mice. Thirty-four adult male Swiss albino mice were divided into four groups as follows: group 1, administered 0.5 ml water; group 2, administered 0.5 ml water + EAC cells; group 3, administered 0.5 ml donkey milk + EAC cells; group 4, administered 0.5 ml donkey milk kefir + EAC cells. We introduced 2.5 x 10 6 EAC cells into each animal by subcutaneous injection. Tap water, donkey milk and donkey milk kefir were administered by gavage for 10 days. Animals were sacrificed on day 11. After measuring the short and long diameters of the tumors, tissues were processed for histology. To determine oxidative stress, cell death and proliferation iNOS and eNOS, active caspase-3 and proliferating cell nuclear antigen were assessed using immunohistochemistry. A TUNEL assay also was used to detect apoptosis. Tumor volume decreased in the donkey milk kefir group compared to the control and donkey milk groups. Tumor volume increased in the donkey milk group compared to the control group. Proliferating cell nuclear antigen levels were higher in the donkey milk kefir group compared to the control and donkey milk groups. The number of apoptotic cells was less in the donkey milk group, compared to the control, whereas it was highest in the donkey milk kefir group. Donkey milk administration increased eNOS levels and decreased iNOS levels, compared to the control group. In the donkey milk kefir group, iNOS levels were significantly lower than those of the control and donkey milk groups, while eNOS levels were similar to the control group. Donkey milk kefir induced apoptosis, suppressed proliferation and decreased co-expression of iNOS and eNOS. Donkey milk promoted development of the tumors. Therefore, donkey milk kefir appears to

  6. Effect of baking and steaming on physicochemical and thermal properties of sweet potato puree preserved by freezing and freeze-drying

    Directory of Open Access Journals (Sweden)

    Bernarda Svrakačić

    2016-01-01

    Full Text Available Thermal treatments could be one of the hurdles in applications of sweet potato purees for food different products formulation. Sweet potato purees (SPP were prepared from raw, baked and steamed roots and they were preserved by freezing and freeze-drying. The effects of baking and steaming on thermal properties (melting temperature-Tm, melting transition energy - ΔH, and glass transition temperatures - Tg of sweet potato (cultivar Beauregard, were measured by means of a Differential scanning calorimetry (DSC. The SPP made from baked roots had higher total and soluble solids (20.32 and 18.95%, respectively than SPP made from raw and steamed roots. It can be also noticed that starch content was reduced by steaming and baking which reflected on amount of total and reducing sugars. The increase of reducing sugars level in baked SPP for 3.78% and steamed for 0.86% SPP was the result of yielding the maltose. The chemical changes of SPP also influenced the thermal behavior such that SPP prepared from baked sweet potato roots had the lowest initial freezing point (-2.80 °C followed by SPP prepared from steamed (-2.63 °C and raw (-0.71 °C roots. The highest energy for melting (transition was needed for SPP prepared from raw potato roots followed by steamed and baked roots, -103.79, -103.63, and -102.90 J/g, respectively. The glass transition in freeze-dried SPP prepared from raw roots was not detected. However, in the freeze-dried SPP prepared from baked and steamed roots the glass transition was detected in the range of 39 and 42 °C but with no significant difference (p > 0.05.

  7. The Influence of High Pressure Thermal Behavior on Friction-induced material transfer During Dry Machining of Titanium

    International Nuclear Information System (INIS)

    Abdel-Aal, H. A.; El Mansori, M.

    2011-01-01

    In this paper we study failure of coated carbide tools due to thermal loading. The study emphasizes the role assumed by the thermo-physical properties of the tool material in enhancing or preventing mass attrition of the cutting elements within the tool. It is shown that within a comprehensive view of the nature of conduction in the tool zone, thermal conduction is not solely affected by temperature. Rather it is a function of the so called thermodynamic forces. These are the stress, the strain, strain rate, rate of temperature rise, and the temperature gradient. Although that within such consideration description of thermal conduction is non-linear, it is beneficial to employ such a form because it facilitates a full mechanistic understanding of thermal activation of tool wear.

  8. Probiotic properties of Lactobacillus strains isolated from Tibetan kefir grains.

    Directory of Open Access Journals (Sweden)

    Yongchen Zheng

    Full Text Available The objective of this study was to evaluate the functional properties of lactic acid bacteria (LAB isolated from Tibetan kefir grains. Three Lactobacillus isolates identified as Lactobacillus acidophilus LA15, Lactobacillus plantarum B23 and Lactobacillus kefiri D17 that showed resistance to acid and bile salts were selected for further evaluation of their probiotic properties. The 3 selected strains expressed high in vitro adherence to Caco-2 cells. They were sensitive to gentamicin, erythromycin and chloramphenicol and resistant to vancomycin with MIC values of 26 µg/ml. All 3 strains showed potential bile salt hydrolase (BSH activity, cholesterol assimilation and cholesterol co-precipitation ability. Additionally, the potential effect of these strains on plasma cholesterol levels was evaluated in Sprague-Dawley (SD rats. Rats in 4 treatment groups were fed the following experimental diets for 4 weeks: a high-cholesterol diet, a high-cholesterol diet plus LA15, a high-cholesterol diet plus B23 or a high-cholesterol diet plus D17. The total cholesterol, triglyceride and low-density lipoprotein cholesterol levels in the serum were significantly (P<0.05 decreased in the LAB-treated rats compared with rats fed a high-cholesterol diet without LAB supplementation. The high-density lipoprotein cholesterol levels in groups B23 and D17 were significantly (P<0.05 higher than those in the control and LA15 groups. Additionally, both fecal cholesterol and bile acid levels were significantly (P<0.05 increased after LAB administration. Fecal lactobacilli counts were significantly (P<0.05 higher in the LAB treatment groups than in the control groups. Furthermore, the 3 strains were detected in the rat small intestine, colon and feces during the feeding trial. The bacteria levels remained high even after the LAB administration had been stopped for 2 weeks. These results suggest that these strains may be used in the future as probiotic starter cultures for

  9. Functional Resilience and Response to a Dietary Additive (Kefir in Models of Foregut and Hindgut Microbial Fermentation In Vitro

    Directory of Open Access Journals (Sweden)

    Gabriel de la Fuente

    2017-06-01

    Full Text Available Stability in gut ecosystems is an important area of study that impacts on the use of additives and is related with several pathologies. Kefir is a fermented milk drink made with a consortium of yeast and bacteria as a fermentation starter, of which the use as additive in companion and livestock animals has increased in the last few years. To investigate the effect of kefir milk on foregut and hindgut digestive systems, an in vitro approach was followed. Either rumen fluid or horse fecal contents were used as a microbial inoculate and the inclusion of kefir (fresh, autoclaved, or pasteurized was tested. Gas production over 72 h of incubation was recorded and pH, volatile fatty acids (VFAs, lactate and ammonia concentration as well as lactic acid (LAB and acetic acid bacteria, and yeast total numbers were also measured. Both direct and indirect (by subtracting their respective blanks effects were analyzed and a multivariate analysis was performed to compare foregut and hindgut fermentation models. Addition of kefir boosted the fermentation by increasing molar concentration of VFAs and ammonia and shifting the Acetate to Propionate ratio in both models but heat processing techniques like pasteurization or autoclaving influenced the way the kefir is fermented and reacts with the present microbiota. In terms of comparison between both models, the foregut model seems to be less affected by the inclusion of Kefir than the hindgut model. In terms of variability in the response, the hindgut model appeared to be more variable than the foregut model in the way that it reacted indirectly to the addition of different types of kefir.

  10. Functional Resilience and Response to a Dietary Additive (Kefir) in Models of Foregut and Hindgut Microbial FermentationIn Vitro.

    Science.gov (United States)

    de la Fuente, Gabriel; Jones, Eleanor; Jones, Shann; Newbold, Charles J

    2017-01-01

    Stability in gut ecosystems is an important area of study that impacts on the use of additives and is related with several pathologies. Kefir is a fermented milk drink made with a consortium of yeast and bacteria as a fermentation starter, of which the use as additive in companion and livestock animals has increased in the last few years. To investigate the effect of kefir milk on foregut and hindgut digestive systems, an in vitro approach was followed. Either rumen fluid or horse fecal contents were used as a microbial inoculate and the inclusion of kefir (fresh, autoclaved, or pasteurized) was tested. Gas production over 72 h of incubation was recorded and pH, volatile fatty acids (VFAs), lactate and ammonia concentration as well as lactic acid (LAB) and acetic acid bacteria, and yeast total numbers were also measured. Both direct and indirect (by subtracting their respective blanks) effects were analyzed and a multivariate analysis was performed to compare foregut and hindgut fermentation models. Addition of kefir boosted the fermentation by increasing molar concentration of VFAs and ammonia and shifting the Acetate to Propionate ratio in both models but heat processing techniques like pasteurization or autoclaving influenced the way the kefir is fermented and reacts with the present microbiota. In terms of comparison between both models, the foregut model seems to be less affected by the inclusion of Kefir than the hindgut model. In terms of variability in the response, the hindgut model appeared to be more variable than the foregut model in the way that it reacted indirectly to the addition of different types of kefir.

  11. Effect of Safflower Oil on Concentration of Conjugated Linoleic Acid of Kefir Prepared by Low-fat Milk.

    Science.gov (United States)

    Farsad-Naeimi, Alireza; Imani, Saeid; Arefhosseini, Seyed R; Alizadeh, Mohammad

    2015-01-01

    Conjugated linoleic acid (CLA) is a special fatty acid in dairy products with unique antioxidant and anti-cancerous effects. Kefir, a milk product, comprises normalized homogenized cow's milk, the fructose and lactulose syrup as well as a symbiotic starter which has improved probiotic characteristics. The study was aimed to discuss patents and to examine the effect of different safflower oil concentrations on CLA content of the kefir drink prepared by low-fat milk. Safflower oil was added at 0.1, 0.3 and 0.5% (V/V) to low-fat cow's milk and six formulations of kefir samples were prepared. The CLA content of the kefir products was measured at pH=6.0 and pH=6.8 by gas chromatography. Acid and bile tolerance of bacterial microenvironment in the products were also determined. Substitution of natural fat content of milk with safflower oil resulted in proportional increase in the CLA contents of kefir in a dose dependent manner. The highest concentration of CLA was found under 0.5% (V/V) of safflower oil at pH 6.0 and temperature of 37 °C. Adding the Safflower oil into milk used for kefir production, increased CLA content from 0.123 (g/100 g) in pure safflower free samples to 0.322 (g/100 g) in samples with 0.5% (V/V) of safflower oil. The current study revealed that substitution of safflower oil with natural fat of cow's milk may help the production of kefir samples with remarkable increase in CLA content of final product.

  12. Evaluation of antagonistic activity of milk fermented with kefir grains of different origins

    Directory of Open Access Journals (Sweden)

    João Paulo Victorino Santos

    2013-10-01

    Full Text Available In this study, the potential of kefir grains, obtained from three different towns/cities in the Southeast Region of Brazil to inhibit the growth of the five pathogenic microorganisms was evaluated. The samples showed the growth inhibition from 42.80-69.15 for Staphylococcus aureus ATCC 6538, 30.73-59.89 for Escherichia coli ATCC 11229, 44.99-73.05 for Salmonela typhi ATCC 6539, 41.45-54.18 for Listeria monocytogenes ATCC 15313 and 70.38-86.80 for Bacillus cereus RIBO 1222-173-S4. These results indicated that the kefir grains evaluated had antagonistic activity toward the different pathogens tested. The ability to inhibit, although differently depending on the regional microbiota, indicated a potential for their use as a functional food.

  13. Kefir exhibits anti‑proliferative and pro‑apoptotic effects on colon adenocarcinoma cells with no significant effects on cell migration and invasion.

    Science.gov (United States)

    Khoury, Nathalie; El-Hayek, Stephany; Tarras, Omayr; El-Sabban, Marwan; El-Sibai, Mirvat; Rizk, Sandra

    2014-11-01

    Kefir, a fermented milk product, exhibits anti‑tumoral activity in vivo; yet its mechanism of action remains elusive. Recent studies have focused on the mechanism of action of kefir on cancer cells in vitro. The current study aims at examining the effect of kefir on cell survival, proliferation, and motility of colorectal cancer (CRC) cells. Kefir's anti‑cancer potential was tested on CRC cell lines, Caco‑2 and HT‑29, through cytotoxicity, proliferation, and apoptotic assays. The expression of certain genes involved in proliferation and apoptosis was measured using reverse transcriptase‑polymerase chain reaction (RT‑PCR) and western blotting. To assess the effect of kefir on cancer metastasis, wound‑healing and time‑lapse movies, in addition to collagen‑based invasion assay, were used. The results show that cell‑free fractions of kefir exhibit an anti‑proliferative effect on Caco‑2 and HT‑29 cells. Analysis of DNA content by flow cytometry revealed the ability of kefir to induce cell cycle arrest at the G1 phase. Kefir was also found to induce apoptosis, as seen by cell death ELISA. Results from RT‑PCR showed that kefir decreases the expression of transforming growth factor α (TGF‑α); and transforming growth factor‑β1 (TGF‑β1) in HT‑29 cells. Western blotting results revealed an upregulation in Bax:Bcl‑2 ratio, confirming the pro‑apoptotic effect of kefir, and an increase in p53 independent‑p21 expression upon kefir treatment. MMP expression was not altered by kefir treatment. Furthermore, results from time‑lapse motility movies, wound‑healing, and invasion assays showed no effect on the motility of colorectal as well as breast (MCF‑7 and MB‑MDA‑231) cancer cells upon kefir treatment. Our data suggest that kefir is able to inhibit the proliferation and induce apoptosis in HT‑29 and Caco‑2 CRC cells, yet it does not exhibit a significant effect on the motility and invasion of these cells in vitro.

  14. Collagen type I from bovine bone. Effect of animal age, bone anatomy and drying methodology on extraction yield, self-assembly, thermal behaviour and electrokinetic potential.

    Science.gov (United States)

    Ferraro, Vincenza; Gaillard-Martinie, Brigitte; Sayd, Thierry; Chambon, Christophe; Anton, Marc; Santé-Lhoutellier, Véronique

    2017-04-01

    Natural collagen is easily available from animal tissues such as bones. Main limitations reported in the use of natural collagen are heterogeneity and loss of integrity during recovery. However, its natural complexity, functionality and bioactivity still remain to be achieved through synthetic and recombinant ways. Variability of physicochemical properties of collagen extracted from bovine bone by acetic acid was then investigated taking into account endogenous and exogenous factors. Endogenous: bovine's bones age (4 and 7 years) and anatomy (femur and tibia); exogenous: thermal treatments (spray-drying and lyophilisation). Scanning electron microscopy, spectroscopy (EDS, FTIR, UV/Vis and CD), differential scanning calorimetry (DSC), centesimal composition, mass spectrometry, amino acids and zeta-potential analysis were used for the purpose. Age correlated negatively with yield of recovery and positively with minerals and proteoglycans content. Comparing the anatomy, higher yields were found for tibias, and higher stability of tibias collagen in solution was noticed. Whatever the age and the anatomy, collagens were able to renature and to self-assemble into tri-dimensional structures. Nonetheless thermal stability and kinetics of renaturation were different. Variability of natural collagen with bone age and anatomy, and drying methodology, may be a crucial advantage to conceive tailor-made applications in either the biological or technical sector. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Bolo de "chocolate" produzido com pó de cupuaçu e kefir "Chocolate" pound cake with cupuassu and kefir

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    Mauricio Sergio Esteller

    2006-09-01

    Full Text Available Nos últimos anos vem ocorrendo a valorização dos recursos e produtos naturais. Cresce em todo o mundo a preocupação com a conservação do meio ambiente e a valorização dos recursos da flora e fauna. É forte a demanda por tecnologias de processo, de produto e de aplicação. Neste estudo foi utilizada formulação padronizada para bolo tipo inglês, substituindo cacau em pó por cupuaçu em pó e com adição de kefir, mantendo-se o total de sólidos. O tempo e a temperatura de assamento foram fixados em 50 minutos e 180 ºC. Foram avaliados a porosidade do miolo, o perfil de textura, cor, umidade, volume específico e densidade da massa. Os resultados mostraram que a adição de pó de cupuaçu não altera as características do bolo padrão elaborado com cacau e que a adição de kefir modifica a textura e a porosidade do miolo.In the last years, natural resources and products have gained the attention of consumers. The concern with the conservation of the environment and the importance of the flora and fauna increases in the whole world. The demand for application, product, and process technologies is strong. In this study, a control chocolate pound cake formula was used changing cocoa powder from the original formula to cupuassu powder and adding kefir, keeping the amounts of total solids. The time and temperature were fixed in 50 minutes and 180 ºC. Crumb porosity, texture profile analysis (TPA, color, moisture, specific volume, and dough density were evaluated. The results showed that cupuassu powder can be used as a cocoa replacer in "chocolate" cake production and that kefir changed the texture and crumb porosity of the cake.

  16. Desarrollo de un alimento funcional deshidratado constituido por microorganismos aislados de Kefir

    OpenAIRE

    Bolla, Patricia Araceli

    2011-01-01

    A pesar de los numerosos estudios sobre probióticos que encontramos en la actualidad, poco se conoce respecto a complejos multicepas. En este trabajo de tesis se propuso: 1- Desarrollar una mezcla microbiana constituida por microorganismos aislados de kefir. 2- Estudiar sus características tecnológicas y potencialmente probióticas. 3- Determinar la capacidad inhibitoria frente a Shigella y Clostridium difficile. 4- Estudiar la capacidad de la mezcla mic...

  17. Kefir Grains Change Fatty Acid Profile of Milk during Fermentation and Storage.

    Science.gov (United States)

    Vieira, C P; Álvares, T S; Gomes, L S; Torres, A G; Paschoalin, V M F; Conte-Junior, C A

    2015-01-01

    Several studies have reported that lactic acid bacteria may increase the production of free fatty acids by lipolysis of milk fat, though no studies have been found in the literature showing the effect of kefir grains on the composition of fatty acids in milk. In this study the influence of kefir grains from different origins [Rio de Janeiro (AR), Viçosa (AV) e Lavras (AD)], different time of storage, and different fat content on the fatty acid content of cow milk after fermentation was investigated. Fatty acid composition was determined by gas chromatography. Values were considered significantly different when pantimutagenic compost, was seen in AV grain (36.6g/100g fatty acids), which may have contributed to increasing the antimutagenic potential in fermented milk. Higher monounsaturated fatty acid (25.8 g/100g fatty acids) and lower saturated fatty acid (72.7 g/100g fatty acids) contents were observed in AV, when compared to other grains, due to higher Δ9-desaturase activity (0.31) that improves the nutritional quality of lipids. Higher oleic acid (25.0 g/100g fatty acids) and monounsaturated fatty acid (28.2g/100g fatty acids) and lower saturated fatty acid (67.2g/100g fatty acids) contents were found in stored kefir relatively to fermented kefir leading to possible increase of antimutagenic and anticarcinogenic potential and improvement of nutritional quality of lipids in storage milk. Only high-lipidic matrix displayed increase polyunsaturated fatty acids after fermentation. These findings open up new areas of study related to optimizing desaturase activity during fermentation in order to obtaining a fermented product with higher nutritional lipid quality.

  18. Kefir Grains Change Fatty Acid Profile of Milk during Fermentation and Storage.

    Directory of Open Access Journals (Sweden)

    C P Vieira

    Full Text Available Several studies have reported that lactic acid bacteria may increase the production of free fatty acids by lipolysis of milk fat, though no studies have been found in the literature showing the effect of kefir grains on the composition of fatty acids in milk. In this study the influence of kefir grains from different origins [Rio de Janeiro (AR, Viçosa (AV e Lavras (AD], different time of storage, and different fat content on the fatty acid content of cow milk after fermentation was investigated. Fatty acid composition was determined by gas chromatography. Values were considered significantly different when p<0.05. The highest palmitic acid content, which is antimutagenic compost, was seen in AV grain (36.6g/100g fatty acids, which may have contributed to increasing the antimutagenic potential in fermented milk. Higher monounsaturated fatty acid (25.8 g/100g fatty acids and lower saturated fatty acid (72.7 g/100g fatty acids contents were observed in AV, when compared to other grains, due to higher Δ9-desaturase activity (0.31 that improves the nutritional quality of lipids. Higher oleic acid (25.0 g/100g fatty acids and monounsaturated fatty acid (28.2g/100g fatty acids and lower saturated fatty acid (67.2g/100g fatty acids contents were found in stored kefir relatively to fermented kefir leading to possible increase of antimutagenic and anticarcinogenic potential and improvement of nutritional quality of lipids in storage milk. Only high-lipidic matrix displayed increase polyunsaturated fatty acids after fermentation. These findings open up new areas of study related to optimizing desaturase activity during fermentation in order to obtaining a fermented product with higher nutritional lipid quality.

  19. Whey permeate fermented with kefir grains shows antifungal effect against Fusarium graminearum.

    Science.gov (United States)

    Gamba, Raúl Ricardo; De Antoni, Graciela; Peláez, Angela León

    2016-05-01

    The objective of the work reported here was to study the antifungal capability of cell-free supernatants obtained from whey permeates after fermentation by the kefir grains CIDCA AGK1 against Fusarium graminearum growth and zearalenone (ZEA) production. The assays were performed in order to study the conidial germination inhibition -in liquid media- and the effect on fungal growth rate and the Latency phase -in solid media. We observed that fermented supernatants of pH 3·5 produced the highest percentages of inhibition of conidial germination. The dilution and, particularly, alkalinisation of them led to the gradual loss of antifungal activity. In the fungal inhibition assays on plates we found that only the highest proportion of supernatant within solid medium had significant antifungal activity, which was determined as fungicidal. There was no ZEA biosynthesis in the medium with the highest proportion of supernatant, whereas at lower concentrations, the mycotoxin production was strain-dependent. From the results obtained we concluded that kefir supernatants had antifungal activity on the F. graminearum strains investigated and inhibited mycotoxin production as well, but in a strain-dependent fashion. The present work constitutes the first report of the effect of the products obtained from the kefir-grain fermentation of whey permeates - a readily available by-product of the dairy industry - on F. graminearum germination, growth, and toxin production.

  20. Mathematical model of CO2release during milk fermentation using natural kefir grains.

    Science.gov (United States)

    Goršek, Andreja; Ritonja, Jožef; Pečar, Darja

    2018-03-12

    Milk fermentation takes place in the presence of various micro-organisms, whereby a variety of dairy products is produced. The oldest among them is kefir, which is usually produced by fermentation of milk with kefir grains. Carbon dioxide (CO 2 ), as one of the process products, also contributes to the characteristic flavor of kefir. The amount of CO 2 generated during fermentation depends on bioprocessing conditions and may change, which is not desirable at the industrial level. In this study we developed a simplified mathematical model of CO 2 release in the milk fermentation process. An intuitive approach based on superposition and experimental analysis was used for the modeling. The chemical system studied was considered as a two-input (temperature, rotational frequency of the stirrer) one-output (CO 2 concentration) dynamic system. Based on an analysis of CO 2 release transients in the case of non-simultaneous stepwise changed input quantities, two differential equations which describe the influence of the two input quantities on the output quantity were defined. The simulation results were verified by experiments. The proposed model can be used for a comprehensive analysis of the process studied and for the design and synthesis of advanced control systems, which will assure a controlled CO 2 release at the industrial level. This article is protected by copyright. All rights reserved.

  1. Adsorption of aflatoxin B1, zearalenone and ochratoxin A by microorganisms isolated from Kefir grains.

    Science.gov (United States)

    Taheur, Fadia Ben; Fedhila, Kais; Chaieb, Kamel; Kouidhi, Bochra; Bakhrouf, Amina; Abrunhosa, Luís

    2017-06-19

    A strategy to reduce the deleterious effects of mycotoxins is to use dietary supplements that contain microorganisms that bind mycotoxins and decrease their gastrointestinal absorption. Novel strains were isolated from a Kefir culture and assessed for their mycotoxin adsorption and biotransformation ability. The most active strains were identified using DNA sequencing, and the stability of microorganism/mycotoxin complexes was evaluated using buffer solutions to simulate the pH conditions in the gastrointestinal tract. Our results showed that the microorganism consortium of Kefir grains adsorbed 82 to 100% of aflatoxin B1 (AFB1), zearalenone (ZEA) and ochratoxin A (OTA) when cultivated in milk. The main strains that were capable of mycotoxin adsorption were identified as Lactobacillus kefiri, Kazachstania servazzii and Acetobacter syzygii. The strain L. kefiri KFLM3 was the most active, adsorbing 80 to 100% of the studied mycotoxins when cultivated in milk. Nonetheless, the strain K. servazzii KFGY7 retained more mycotoxin after the desorption experiments (65, 69 and 67% for AFB1, OTA and ZEA, respectively). These findings suggest that Kefir consumption may help to reduce gastrointestinal absorption of these mycotoxins and consequently reduce their toxic effects. The isolated strains may be of interest for the development of fermented dairy products for human consumption that have a new probiotic characteristic, the adsorption of mycotoxins. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Effects of Kefir as a Probiotic Source on the Performance and Health of Young Dairy Calves

    Directory of Open Access Journals (Sweden)

    Sema Satık

    2017-02-01

    Full Text Available The aim of this study was to investigate the effect of kefir as a probiotic on the performance and health status of calves. Thirty Holstein female calves with 3-day-old were randomly allocated to three treatment groups: Control (without any probiotic, probiotic (a commercial probiotic mixture-3 g/d/calf bacteria-based and 2 g/d/calf yeast-based and kefir (20 ml/d/calf. The calves were weaned at 56 days of age. The experiment was performed in 70 days. Treatment had no effect (P>0.05 on weaning and final body weight and starter intake. Although differences in weight gain were not significant (P>0.05, there were trend to increase by probiotic treatments during 0-14 days. Probiotic treatments tended to have a positive effect on the population of the fecal lactic acid bacteria at 14 days. The results of the study indicated that kefir as a natural probiotic in calf nutrition may be beneficial during the first weeks of life.

  3. Kefir Grains Change Fatty Acid Profile of Milk during Fermentation and Storage

    Science.gov (United States)

    Vieira, C. P.; Álvares, T. S.; Gomes, L. S.; Torres, A. G.; Paschoalin, V. M. F.; Conte-Junior, C. A.

    2015-01-01

    Several studies have reported that lactic acid bacteria may increase the production of free fatty acids by lipolysis of milk fat, though no studies have been found in the literature showing the effect of kefir grains on the composition of fatty acids in milk. In this study the influence of kefir grains from different origins [Rio de Janeiro (AR), Viçosa (AV) e Lavras (AD)], different time of storage, and different fat content on the fatty acid content of cow milk after fermentation was investigated. Fatty acid composition was determined by gas chromatography. Values were considered significantly different when pkefir relatively to fermented kefir leading to possible increase of antimutagenic and anticarcinogenic potential and improvement of nutritional quality of lipids in storage milk. Only high-lipidic matrix displayed increase polyunsaturated fatty acids after fermentation. These findings open up new areas of study related to optimizing desaturase activity during fermentation in order to obtaining a fermented product with higher nutritional lipid quality. PMID:26444286

  4. Kefir immobilized on corn grains as biocatalyst for lactic acid fermentation and sourdough bread making.

    Science.gov (United States)

    Plessas, Stavros; Alexopoulos, Athanasios; Bekatorou, Argyro; Bezirtzoglou, Eugenia

    2012-12-01

    The natural mixed culture kefir was immobilized on boiled corn grains to produce an efficient biocatalyst for lactic acid fermentation with direct applications in food production, such as sourdough bread making. The immobilized biocatalyst was initially evaluated for its efficiency for lactic acid production by fermentation of cheese whey at various temperatures. The immobilized cells increased the fermentation rate and enhanced lactic acid production compared to free kefir cells. Maximum lactic acid yield (68.8 g/100 g) and lactic acid productivity (12.6 g/L per day) were obtained during fermentation by immobilized cells at 37 °C. The immobilized biocatalyst was then assessed as culture for sourdough bread making. The produced sourdough breads had satisfactory specific loaf volumes and good sensory characteristics. Specifically, bread made by addition of 60% w/w sourdough containing kefir immobilized on corn was more resistant regarding mould spoilage (appearance during the 11(th) day), probably due to higher lactic acid produced (2.86 g/Kg of bread) compared to the control samples. The sourdough breads made with the immobilized biocatalyst had aroma profiles similar to that of the control samples as shown by headspace SPME GC-MS analysis. © 2012 Institute of Food Technologists®

  5. Bacteria and yeast microbiota in milk kefir grains from different Italian regions.

    Science.gov (United States)

    Garofalo, Cristiana; Osimani, Andrea; Milanović, Vesna; Aquilanti, Lucia; De Filippis, Francesca; Stellato, Giuseppina; Di Mauro, Simone; Turchetti, Benedetta; Buzzini, Pietro; Ercolini, Danilo; Clementi, Francesca

    2015-08-01

    Kefir grains are a unique symbiotic association of different microrganisms, mainly lactic acid bacteria, yeasts and occasionally acetic acid bacteria, cohabiting in a natural polysaccharide and a protein matrix. The microbial composition of kefir grains can be considered as extremely variable since it is strongly influenced by the geographical origin of the grains and by the sub-culturing method used. The aim of this study was to elucidate the bacteria and yeast species occurring in milk kefir grains collected in some Italian regions by combining the results of scanning electron microscopy analysis, viable counts on selective culture media, PCR-DGGE and pyrosequencing. The main bacterial species found was Lactobacillus kefiranofaciens while Dekkera anomala was the predominant yeast. The presence of sub-dominant species ascribed to Streptococcus thermophilus, Lactococcus lactis and Acetobacter genera was also highlighted. In addition, Lc. lactis, Enterococcus sp., Bacillus sp., Acetobacter fabarum, Acetobacter lovaniensis and Acetobacter orientalis were identified as part of the cultivable community. This work further confirms both the importance of combining culture-independent and culture-dependent approaches to study microbial diversity in food and how the combination of multiple 16S rRNA gene targets strengthens taxonomic identification using sequence-based identification approaches. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. STUDI EFFEKTIVITAS KEFIR BENING DAN MENIRAN (Philanthus niruri TERHADAP PENURUNAN KADAR GLUKOSA DARAH PADA HEWAN TIKUS WISTAR HIPERGLIKEMIA DIINDUKSI STREPTOZOTOCIN

    Directory of Open Access Journals (Sweden)

    Judiono .

    2014-09-01

    were given feed refers to the AIN 93. Fasting glucose levels before and after treatment were measured by Super (Glucocard II enzimatic method. The results showed that body weight increased in all treatments, except meniran, however the increaments were not differ significantly. Changes in body weight of insulin group were 13.800 + 16.104 g, kefir treatment amounted to 13.812 + 21.294, and meniran increased about 18.394 + 16.225. Changes in blood glucose in the insulin group about -118.571+55.815 mg/dL, kefir treatment at -102.875+60.454, while meniran group -66,625+37,784. In contrast, the positive control group tended to increase glucose levels. Conclusion In vitro, plain kefir and meniran potentially lowered blood glucose levels. However, kefir showed lowered glucose level better than meniran. Futher research needs to study bio- molecular mechanisms of the decline in the future. Key words: diabetes mellitus, meniran, plain kefir, streptozotocin (STZ, hyperglycemic rat

  7. Kefir improves fatty liver syndrome by inhibiting the lipogenesis pathway in leptin-deficient ob/ob knockout mice.

    Science.gov (United States)

    Chen, H-L; Tung, Y-T; Tsai, C-L; Lai, C-W; Lai, Z-L; Tsai, H-C; Lin, Y-L; Wang, C-H; Chen, C-M

    2014-09-01

    Fatty liver disease is commonly associated with obesity, insulin resistance and diabetes. Severe fatty liver is sometimes accompanied by steatohepatitis and may lead to the development of hepatocellular carcinoma. At present, there is no effective treatment for non-alcoholic fatty liver disease (NAFLD); thus, recent investigations have focused on developing effective therapeutics to treat this condition. This study aimed to evaluate the effects of kefir on the hepatic lipid metabolism of ob/ob mice, which are commonly used to model fatty liver disease. In this study, we used leptin receptor-deficient ob/ob mice as an animal disease model of NAFLD. Six-week-old ob/ob mice were orally administered the dairy product kefir (140 mg kg(-1) of body weight (BW) per day) for 4 weeks. The data demonstrated that kefir improved fatty liver syndrome on BW, energy expenditure and basal metabolic rate by inhibiting serum glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT) activities (Pkefir administration also significantly reduced the macrovesicular fat quantity in liver tissue. In addition, kefir markedly decreased the expression of the genes sterol regulatory element-binding protein 1 (SREBP1), fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC) (Pkefir improves NAFLD on BW, energy expenditure and basal metabolic rate by inhibiting the lipogenesis pathway and that kefir may have the potential for clinical application to the prevention or treatment of NAFLD.

  8. Freeze-dried EchiTAb+ICP antivenom formulated with sucrose is more resistant to thermal stress than the liquid formulation stabilized with sorbitol.

    Science.gov (United States)

    Herrera, María; Segura, Álvaro; Sánchez, Adriana; Sánchez, Andrés; Vargas, Mariángela; Villalta, Mauren; Harrison, Robert A; Gutiérrez, José María; León, Guillermo

    2017-07-01

    EchiTAb + ICP is a pan-African antivenom used for the treatment of snakebite envenomation in rural sub-Saharan African communities, where the cold chain can be difficult to maintain. To develop a formulation of EchiTAb + ICP that can be distributed and stored without refrigeration, we submitted three different formulations of EchiTAb + ICP: control (i.e. liquid antivenom formulated without stabilizer), liquid antivenom stabilized with sorbitol, and freeze-dried antivenom formulated with sucrose, to an accelerated stability study (i.e. 38 ± 2 °C and 75% relative humidity for 6 months). We analyzed changes in color, residual humidity, reconstitution time (for freeze-dried preparation), pH, osmolality, total protein concentration, antibody monomers content, turbidity, bacterial endotoxins, and pre-clinical neutralizing efficacy of the lethal effect of Echis ocellatus venom at 0, 3 and 6 months. In the control formulation, instability was evidenced by the development of a yellow coloration and an increment in aggregation and turbidity, without change in its neutralizing activity. The sorbitol-stabilized formulation did not develop marked aggregation or turbidity, but instability was evidenced by the development of yellow coloration and a drop in the neutralizing potency. The freeze-dried formulation maintained its neutralizing potency and did not show marked signs of instability, thus indicating that freeze-drying could confer EchiTAb + ICP with improved thermal stability required for distribution and storage at room temperature in sub-Saharan Africa. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Thermal conductive properties of wood, green or dry, from -40° to +100° C: a literature review

    Science.gov (United States)

    H. Peter Steinhagen

    1977-01-01

    This literature review was conducted in connection with a study on heat transfer in frozen logs. A combination of data by two researchers on specific heat and thermal conductivity and diffusivity in the radial direction of wood, at various temperatures and moisture contents, is discussed and compared with data from other sources. Limited information found for the...

  10. Thermal Stability of Oil Palm Empty Fruit Bunch (OPEFB) Nanocrystalline Cellulose: Effects of post-treatment of oven drying and solvent exchange techniques

    Science.gov (United States)

    Indarti, E.; Marwan; Wanrosli, W. D.

    2015-06-01

    Nanocrystallinecellulose (NCC) from biomass is a promising material with huge potentials in various applications. A big challenge in its utilization is the agglomeration of the NCC's during processing due to hydrogen bonding among the cellulose chains when in close proximity to each other. Obtaining NCC's in a non-agglomerated and non-aqueous condition is challenging. In the present work NCC's was isolated from oil palm empty fruit bunch (OPEFB) using TEMPO-oxidation reaction method. To obtain non-agglomerated and non-aqueous products, the NCC's underwent post-treatment using oven drying (OD) and solvent exchanged (SE) techniques. The thermal stability of all samples was determined from TGA and DTG profiles whilst FTIR was used to analyzethe chemical modifications that occurred under these conditions. NCC-SE has better thermal stability than the NCC-OD and its on-set degradation temperature and residue are also higher. FTIR analysis shows that NCC-SE has a slightly different chemical composition whereby the absorption band at 1300 cm-1 (due to C-O symmetric stretching) is absent as compared to NCC-OD indicating that in NCC-SE the carboxylate group is in acid form which contribute to its thermal stability

  11. Charging-discharging characteristics of macro-encapsulated phase change materials in an active thermal energy storage system for a solar drying kiln

    Directory of Open Access Journals (Sweden)

    Kumar Shailendra

    2017-01-01

    Full Text Available The present study explores suitability of two phase change materials (PCM for development of an active thermal storage system for a solar drying kiln by studying their melting and solidification behaviors. A double glass glazing prototype solar kiln was used in the study. The storage system consisted of a water storage tank with PCM placed inside the water in high density polyethylene containers. The water in the tank was heated with help of solar energy using an evacuated tube collector array. The melting and solidification temperature curves of PCM were obtained by charging and discharging the water tank. The study illustrated the utility of the PCM in using the stored thermal energy during their discharge to enhance the temperature inside the kiln. The rate of temperature reduction was found to be higher for paraffin wax as compared to a fatty acid based PCM. The water temperature during the discharge of the PCM showed dependence on the discharge characteristics of each PCM suggesting their suitability in designing active thermal storage systems.

  12. The Effect of Combination Carrot Juice (Daucus carota L. and Hunkwee Flour in Manufacturing Kefir Ice Cream on Physical and Chemical Quality of Kefir Ice Cream

    Directory of Open Access Journals (Sweden)

    Ilma Mahdiana

    2017-03-01

    Full Text Available The purpose of this research was to determine the best combination of carrot juice (CJ and hunkwee flour (HF on manufacturing of kefir ice cream. The method of this research was experiment with Completely Randomized Design, 4 treatments and 4 replication, the treatments were without carrot juice + HF 5% (P0, CJ 1.5% + HF 3.5% (P1, CJ 3% + HF 2% (P2, CJ 4.5% + HF 0.5% (P3, the presentage based on Ice Cream Mix (ICM. The variables measured were antioxidant activity, viscosity, total solid and organoleptic (textur, taste and aroma. The data was analized by using Analysis Of Variance (ANOVA continued by Honestly Significance Difference (HSD test. The result of this research showed that the combination of carrot juice and hunkwee flour gave highly significant difference effect (P0.05 on aroma. Conclusion: the combination of carrot juice 1.5% + hunkwee flour 3.5% (P1 in kefir ice cream gave the best result.

  13. Report of Task Group on Ex-Vessel Thermal-Hydraulics Corium/concrete interactions and combustible gas distribution in large dry containments

    International Nuclear Information System (INIS)

    1987-11-01

    The Task Group on Ex-Vessel Thermal-Hydraulics was established by the PWG 2 to address the physical processes that occur in the ex-vessel phase of severe accidents, to study their impact on containment loading and failure, and to assess the available calculation methods. This effort is part of an overall CSNI effort to come to an international understanding of the issues involved. The Task Group decided to focus its initial efforts on the Large Dry Containment used extensively to contain the consequences of postulated (design basis) accidents in Light Water Reactors (LWR). Although such containments have not been designed with explicit consideration of severe accidents, recent assessments indicate a substantial inherent capability for these accidents. The Task Group has examined the loads likely to challenge the integrity of the containment, and considered the calculation of the containment's response. This report is the outcome of this effort

  14. Estudio de la capacidad de los microorganismos del kefir para inhibir el desarrollo fúngico y para secuestrar micotoxinas

    OpenAIRE

    León Peláez, Ángela María

    2013-01-01

    Objetivo general Estudiar la potencialidad de los microorganismos del gránulo de kefir y sus metabolitos para inhibir el desarrollo de hongos filamentosos, toxicogénicos y no toxicogénicos y para secuestrar micotoxinas. Objetivos específicos - Estudiar el efecto antifúngico de bacterias, levaduras y productos fermentados con kefir sobre los hongos toxicogénicos y no toxicogénicos. - Analizar el efecto que ejercen los ácidos orgánicos puros y en mezcla...

  15. Improving biogas production from anaerobic co-digestion of sewage sludge with a thermal dried mixture of food waste, cheese whey and olive mill wastewater.

    Science.gov (United States)

    Maragkaki, A E; Vasileiadis, I; Fountoulakis, M; Kyriakou, A; Lasaridi, K; Manios, T

    2018-01-01

    Anaerobic co-digestion of sewage sludge and other organic wastes at a wastewater treatment plant (WWTP) is a promising method for both energy and material recovery. However, transportation and storage of wastes to WWTP may be the bottleneck for the successful implementation of this technology. In case of wet wastes and wastewater it is possible to reduce their volume and as a result the transportation and storage cost by using a drying process. During this study, the optimization of biogas production from sewage sludge (SS) was attempted by co-digesting with a dried mixture of food waste, cheese whey and olive mill wastewater (FCO). A series of laboratory experiments were performed in continuously-operating reactors at 37°C, fed with thermal dried mixtures of FCO at concentrations of 3%, 5% and 7%. The overall process was designed with a hydraulic retention time (HRT) of 24days. FCO addition can boost biogas yields if the mixture exceeds 3% (v/v) concentration in the feed. Any further increase of 5% FCO causes a small increase in biogas production. The reactor treating the sewage sludge produced 287ml CH 4 /L reactor /d before the addition of FCO and 815ml CH 4 /L reactor /d (5% v/v in the feed). The extra FCO-COD added (7% FCO v/v) to the feed did not have a negative effect on reactor performance, but seemed to have the same results. In all cases, the estimated biodegradability of mixtures was over 80%, while the VS removal was 22% for the maximum biomethane production (5% v/v). Moreover, co-digestion improved biogas production by 1.2-2.7 times. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Short-Term Effects of Kefir-Fermented Milk Consumption on Bone Mineral Density and Bone Metabolism in a Randomized Clinical Trial of Osteoporotic Patients.

    Directory of Open Access Journals (Sweden)

    Min-Yu Tu

    Full Text Available Milk products are good sources of calcium that may reduce bone resorption and help prevent bone loss as well as promote bone remodeling and increase bone formation. Kefir is a product made by kefir grains that degrade milk proteins into various peptides with health-promoting effects, including antithrombotic, antimicrobial and calcium-absorption enhancing bioactivities. In a controlled, parallel, double-blind intervention study over 6 months, we investigated the effects of kefir-fermented milk (1,600 mg supplemented with calcium bicarbonate (CaCO3, 1,500 mg and bone metabolism in 40 osteoporosis patients, and compared them with CaCO3 alone without kefir supplements. Bone turnover markers were measured in fasting blood samples collected before therapy and at 1, 3, and 6 months. Bone mineral density (BMD values at the spine, total hip, and hip femoral neck were assessed by dual-energy x-ray absorptiometry (DXA at baseline and at 6 months. Among patients treated with kefir-fermented milk, the relationships between baseline turnover and 6 months changes in DXA-determined BMD were significantly improved. The serum β C-terminal telopeptide of type I collagen (β-CTX in those with T-scores > -1 patients significantly decreased after three months treatment. The formation marker serum osteocalcin (OC turned from negative to positive after 6 months, representing the effect of kefir treatment. Serum parathyroid hormone (PTH increased significantly after treatment with kefir, but decreased significantly in the control group. PTH may promote bone remodeling after treatment with kefir for 6 months. In this pilot study, we concluded that kefir-fermented milk therapy was associated with short-term changes in turnover and greater 6-month increases in hip BMD among osteoporotic patients.ClinicalTrials.gov NCT02361372.

  17. Short-Term Effects of Kefir-Fermented Milk Consumption on Bone Mineral Density and Bone Metabolism in a Randomized Clinical Trial of Osteoporotic Patients.

    Science.gov (United States)

    Tu, Min-Yu; Chen, Hsiao-Ling; Tung, Yu-Tang; Kao, Chao-Chih; Hu, Fu-Chang; Chen, Chuan-Mu

    2015-01-01

    Milk products are good sources of calcium that may reduce bone resorption and help prevent bone loss as well as promote bone remodeling and increase bone formation. Kefir is a product made by kefir grains that degrade milk proteins into various peptides with health-promoting effects, including antithrombotic, antimicrobial and calcium-absorption enhancing bioactivities. In a controlled, parallel, double-blind intervention study over 6 months, we investigated the effects of kefir-fermented milk (1,600 mg) supplemented with calcium bicarbonate (CaCO3, 1,500 mg) and bone metabolism in 40 osteoporosis patients, and compared them with CaCO3 alone without kefir supplements. Bone turnover markers were measured in fasting blood samples collected before therapy and at 1, 3, and 6 months. Bone mineral density (BMD) values at the spine, total hip, and hip femoral neck were assessed by dual-energy x-ray absorptiometry (DXA) at baseline and at 6 months. Among patients treated with kefir-fermented milk, the relationships between baseline turnover and 6 months changes in DXA-determined BMD were significantly improved. The serum β C-terminal telopeptide of type I collagen (β-CTX) in those with T-scores > -1 patients significantly decreased after three months treatment. The formation marker serum osteocalcin (OC) turned from negative to positive after 6 months, representing the effect of kefir treatment. Serum parathyroid hormone (PTH) increased significantly after treatment with kefir, but decreased significantly in the control group. PTH may promote bone remodeling after treatment with kefir for 6 months. In this pilot study, we concluded that kefir-fermented milk therapy was associated with short-term changes in turnover and greater 6-month increases in hip BMD among osteoporotic patients. ClinicalTrials.gov NCT02361372.

  18. Design and construction of a hybrid system of heating air by combustion of biomass and solar radiation, using phase change material (PCM as a source of thermal storage, for cassava drying

    Directory of Open Access Journals (Sweden)

    Ramiro Torres-Gallo

    2017-05-01

    Full Text Available This study consisted of designing, building and validation a hybrid system of heating air by combustion of biomass and solar radiation, using phase change material (PCM as a thermal storage source, for cassava drying, a small scale. The dryer consists of a centrifugal fan, two solar collectors, a fuel burner solid (rice husk and a tray dryer. System validation was performed drying up Yucca. The PCM allowed to follow the drying process, even when the solar radiation was below 116,22 ± 31,94 W / m2, being able to maintain drying air temperatures in the two solar collectors at 46 ± 4, 29 ° C and 51 ± 4.08 ° C for an additional 45 min. The drying time was 10 h and 45 min, the efficiency of the solar collectors was 43.91 % and the rice husk burner of 36.72 %.

  19. Dry anaerobic co-digestion of food waste and cattle manure: Impact of total solids, substrate ratio and thermal pre treatment on methane yield and quality of biomanure.

    Science.gov (United States)

    Arelli, Vijayalakshmi; Begum, Sameena; Anupoju, Gangagni Rao; Kuruti, Kranti; S, Shailaja

    2018-04-01

    The objective of the present study is to assess the impact of TS concentration, substrate mixing ratio (co digestion) and thermal pretreatment on biogas production, methane yield, VS reduction (%) and quality of biomanure through dry anaerobic digestion (DAD) of food waste (FW) and cattle manure (CM). Results divulged that the optimum methane yield and biomanure of 0.18 and 0.21 m 3 CH 4 /(kg VS reduced) and 3.15 and 2.8 kg/kg waste was obtained from FW at TS of 25% and 30% at an HRT of 41 and 31 days respectively whereas it was 0.32 and 0.43 m 3 CH 4 /(kg VS reduced) and 2.2 and 1.15 kg/kg waste from pretreated FW at an HRT of 16 and 20 days correspondingly. Improvement of methane from 62 to 81% was obtained due to thermal pretreatment. The highest nutrient recovery in terms of N, P, K was found to be 5.14, 2.6 and 3.2 respectively. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Spray-Dried Cellulose Nanofibril-Reinforced Polypropylene Composites for Extrusion-Based Additive Manufacturing: Nonisothermal Crystallization Kinetics and Thermal Expansion

    Directory of Open Access Journals (Sweden)

    Lu Wang

    2018-02-01

    Full Text Available Isotactic polypropylene (iPP is a versatile polymer. It accounts for the second-largest polymer consumption worldwide. However, iPP is difficult to 3D print via extrusion-based processing. This is attributable to its rapid crystallization rate. In this study, spray-dried cellulose nanofibrils (SDCNF and maleic anhydride polypropylene (MAPP were investigated to reveal their effects on the nonisothermal crystallization kinetics and thermal expansion of iPP. SDCNF at 3 wt % and 30 wt % accelerated the crystallization rate of iPP, while SDCNF at 10 wt % retarded the crystallization rate by restricting crystal growth and moderately increasing the nucleation density of iPP. Additionally, adding MAPP into iPP/SDCNF composites accelerated the crystallization rate of iPP. The effective activation energy of iPP increased when more than 10 wt % SDCNF was added. Scanning electron microscopy and polarized light microscopy results indicated that high SDCNF content led to a reduced gap size among SDCNF, which hindered the iPP crystal growth. The coefficient of thermal expansion of iPP/SDCNF10% was 11.7% lower than the neat iPP. In summary, SDCNF, at 10 wt %, can be used to reduce the warping of iPP during extrusion-based additive manufacturing.

  1. Solid state stability of proteins III: calorimetric (DSC) and spectroscopic (FTIR) characterization of thermal denaturation in freeze dried human growth hormone (hGH).

    Science.gov (United States)

    Pikal, Michael J; Rigsbee, Daniel; Roy, Michael L

    2008-12-01

    This research is a study of the changes in secondary structure (Fourier transform infrared spectroscopy, FTIR), aggregation, and loss of the magnitude of the heat of denaturation upon scanning to and partially through the temperature range of the thermal denaturation peak of a model protein, human growth hormone (hGH). We study two formulations, a system of essentially pure protein (with a trace of phosphate buffer) and a system formulated with trehalose in a 3:1 trehalose:hGH weight ratio. The extent of denaturation is measured by loss of secondary structure by FTIR, the loss of heat of denaturation by differential scanning calorimetry (DSC), and the fraction of protein aggregated by HPLC. We examine loss of structure on heating to the DSC onset of thermal denaturation and restoration of structure by cooling below the denaturation temperature and holding to (nominally) allow time for refolding, and we also examine restoration of structure upon dissolving and refreeze drying samples heated to selected temperatures in the denaturation range. We find that denaturation occurs only above the glass transition temperature, is highly cooperative, and is only reversible by redissolving the "denatured" formulated (trehalose) solid. Further, all measures of the extent of denaturation are in essential agreement.

  2. Thermal design of heat-exchangeable reactors using a dry-sorbent CO2 capture multi-step process

    International Nuclear Information System (INIS)

    Moon, Hokyu; Yoo, Hoanju; Seo, Hwimin; Park, Yong-Ki; Cho, Hyung Hee

    2015-01-01

    The present study proposes a multi-stage CO 2 capture process that incorporates heat-exchangeable fluidized-bed reactors. For continuous multi-stage heat exchange, three dry regenerable sorbents: K 2 CO 3 , MgO, and CaO, were used to create a three-stage temperature-dependent reaction chain for CO 2 capture, corresponding to low (50–150 °C), middle (350–650 °C), and high (750–900 °C) temperature stages, respectively. Heat from carbonation in the high and middle temperature stages was used for regeneration for the middle and low temperature stages. The feasibility of this process is depending on the heat-transfer performance of the heat-exchangeable fluidized bed reactors as the focus of this study. The three-stage CO 2 capture process for a 60 Nm 3 /h CO 2 flow rate required a reactor area of 0.129 and 0.130 m 2 for heat exchange between the mid-temperature carbonation and low-temperature regeneration stages and between the high-temperature carbonation and mid-temperature regeneration stages, respectively. The reactor diameter was selected to provide dense fluidization conditions for each bed with respect to the desired flow rate. The flow characteristics and energy balance of the reactors were confirmed using computational fluid dynamics and thermodynamic analysis, respectively. - Highlights: • CO 2 capture process is proposed using a multi-stage process. • Reactor design is conducted considering heat exchangeable scheme. • Reactor surface is designed by heat transfer characteristics of fluidized bed

  3. Brazilian Kefir-Fermented Sheep's Milk, a Source of Antimicrobial and Antioxidant Peptides.

    Science.gov (United States)

    de Lima, Meire Dos Santos Falcão; da Silva, Roberto Afonso; da Silva, Milena Fernandes; da Silva, Paulo Alberto Bezerra; Costa, Romero Marcos Pedrosa Brandão; Teixeira, José António Couto; Porto, Ana Lúcia Figueiredo; Cavalcanti, Maria Taciana Holanda

    2017-12-28

    Fermented milks are a source of bioactive peptides and may be considered as functional foods. Among these, sheep's milk fermented with kefir has not been widely studied and its most relevant properties need to be more thoroughly characterized. This research study is set out to investigate and evaluate the antioxidant and antimicrobial properties of peptides from fermented sheep's milk in Brazil when produced by using kefir. For this, the chemical and microbiological composition of the sheep's milk before and after the fermentation was evaluated. The changes in the fermented milk and the peptides extracted before the fermentation and in the fermented milk during its shelf life were verified. The antimicrobial and antioxidant activities of the peptides from the fermented milk were evaluated and identified according to the literature. The physicochemical properties and mineral profile of the fermented milk were like those of fresh milk. The peptide extract presented antimicrobial activity and it was detected that 13 of the 46 peptides were able to inhibit the growth of pathogenic microorganisms. A high antioxidant activity was observed in the peptides extracted from fermented milk (3.125 mg/mL) on the 28th day of storage. Two fractions displayed efficient radical scavenging properties by DPPH and ABTS methods. At least 11 peptides distributed in the different fractions were identified by tandem mass spectrometry. This sheep's milk fermented by Brazilian kefir grains, which has antioxidant and antimicrobial activities and probiotic microorganisms, is a good candidate for further investigation as a source for bioactive peptides. The fermentation process was thus a means by which to produce potential bioactive peptides.

  4. Kualitas Mikrobiologis dan Kimiawi Kefir Susu Kambing dengan Penambahan Lactobacillus acidophilus FNCC 0051 dan Tepung Kulit Pisang Kepok (Musa Paradisiaca

    Directory of Open Access Journals (Sweden)

    Dwitiya Martharini

    2017-03-01

    Full Text Available This experiment was carried out to investigate the effect of  plantain peel flour and Lactobacillus acidophilus FNCC 0051 on the microbiological and chemical quality of goat milk kefir. Kefir was made from goat’s milk with 3 % of kefir grain (w/v and  Lactobacillus acidophilus FNCC 0051 (0, 1 and 3 % (v/v and  plantain peel flour (0, 1 and 2 % (w/v. All treatments were  incubated at room temperature (± 28.5 °C for 10 hours, until the pH dropped to 4.2-4.6.The quality of Kefir was evaluated by  microbiological analysis (total of lactic acid bacteria, probiotics  viability, total yeast and chemical analysis (pH, lactose content,  alcohol content, fat content and dietary fiber. The data of total lactic acid bacteria, probiotics viability, total yeast, pH, lactose  content, alcohol content, fat content were evaluated by analysis of variance and followed by Duncan’s New Multiple Range Test  (DMRT. Data of dietary fiber was evaluated by descriptive analysis. The research result showed that the addition of  Lactobacillus acidophilus FNCC 0051 had a significant effect (p ≤  0.05 on decreasing pH, alcohol content and increasing total lactic  acid bacteria and probiotic viability. Plantain peel flour had  significantl effect (p ≤ 0.05 on increasing alcohol content and  total lactic acid bacteria. Kefir had 9.51 log cfu mL-1 of lactic acid  bacteria total; 8.65 log cfu mL-1 of probiotic viability; 6.13 log cfu  mL-1 of total yeast; 4.85 of pH; 3.14 % of lactose content; 0.096 % of alcohol content; 5.33 % of fat content; and 10.49 % of dietary fiber. This research concluded that kefir quality for all  treatments kefir were complied with Codex Standard 234-2003  while the best treatment was the kefir with the addition of 3 %  Lactobacillus acidophilus FNCC 0051 and 1 % flour banana peel.   ABSTRAK Penelitian ini bertujuan untuk mengetahui pengaruh penambahan tepung kulit pisang dan Lactobacillus acidophilus FNCC 0051  terhadap

  5. Effects of Microbial Transglutaminase on Physicochemical, Microbial and Sensorial Properties of Kefir Produced by Using Mixture Cow's and Soymilk.

    Science.gov (United States)

    Temiz, Hasan; Dağyıldız, Kübra

    2017-01-01

    The objective of this research was to investigate the effects microbial transglutaminase (m-TGs) on the physicochemical, microbial and sensory properties of kefir produced by using mix cow and soymilk. Kefir batches were prepared using 0, 0.5, 1 and 1.5 Units m-TGs for per g of milk protein. Adding m-TGs to milk caused an increase in the pH and viscosity and caused a decrease in titratable acidity and syneresis in the kefir samples. Total bacteria, lactobacilli and streptococci counts decreased, while yeast counts increased in all the samples during storage. Alcohols and acids compounds have increased in all the samples except in the control samples, while carbonyl compounds have decreased in all the samples during storage (1-30 d). The differences in the percentage of alcohols, carbonyl compounds and acids in total volatiles on the 1st and the 30th d of storage were observed at 8.47-23.52%, 6.94-25.46% and 59.64-63.69%, respectively. The consumer evaluation of the kefir samples showed that greater levels of acceptability were found for samples which had been added 1.5 U m-TGs for per g of milk protein.

  6. Selected Lactobacillus strains isolated from sugary and milk kefir reduce Salmonella infection of epithelial cells in vitro.

    Science.gov (United States)

    Zavala, L; Golowczyc, M A; van Hoorde, K; Medrano, M; Huys, G; Vandamme, P; Abraham, A G

    2016-09-01

    The isolation of potentially probiotic strains and the subsequent study of their properties are very important steps to gain insight in the health benefits ascribed to sugary and milk kefir. The aim of the present study was to characterise fifteen Lactobacillus strains isolated from these beverages by determining some surface properties and their ability to antagonise enterocyte cell damage after Salmonella infection in vitro. Lactobacillus surface properties were determined by hydrophobicity, autoaggregation, and coaggregation assays with Salmonella. In addition, lactobacilli adhesion to Caco-2/TC-7 cells and the effect on Salmonella invasion were evaluated. Finally, the disassembly of F-actin cytoskeleton on intestinal epithelial cells was assayed in vitro when Salmonella infection was performed in the presence of selected Lactobacillus strains. Ten out of the 15 strains showed a high adhesion capacity to Caco-2/TC-7 cells. Most of the strains were hydrophilic and non-autoaggregating. Strains isolated from sugary kefir were non-coaggregating with Salmonella, while strains Lactobacillus paracasei CIDCA 83120, 83121, 83123, 83124, 8339, 83102 isolated from milk kefir were able to coaggregate after 1 h. L. paracasei CIDCA 8339 and Lactobacillus kefiri CIDCA 83102 were able to diminish Salmonella invasion to the enterocytes. An antagonistic effect on cytoskeleton disruption elicited by the pathogen was also demonstrated. Our results suggest that both strains isolated from milk kefir could be considered as appropriate probiotic candidates.

  7. Análise da fermentação alcoólica do kefir em biorreator

    Directory of Open Access Journals (Sweden)

    Renata Ferreira Miranda

    2015-09-01

    Full Text Available A cana-de-açúcar é a principal matéria-prima utilizada no Brasil para fermentação alcoólica. Neste trabalho, objetivou-se avaliar o efeito do kefir quanto à sua viabilidade para produção de etanol por meio da fermentação alcoólica. Os grãos de kefir se constituem de uma associação simbiótica de leveduras, bactérias ácido-láticas e bactérias ácido-acéticas tradicionalmente utilizadas para a produção de leites fermentados de baixo teor alcoólico, o que gera uma bebida associada à longevidade e considerada terapêutica. A partir de fermentação conduzida em biorreator piloto verificou-se o consumo de açúcar e produção de etanol com os grãos de kefir. O estudo realizado apresentou resultados satisfatórios para fermentação do kefir na produção de etanol.

  8. Evaluation of a potentially probiotic non-dairy beverage developed with honey and kefir grains: Fermentation kinetics and storage study.

    Science.gov (United States)

    Fiorda, Fernanda A; de Melo Pereira, Gilberto V; Thomaz-Soccol, Vanete; Rakshit, Sudip K; Soccol, Carlos R

    2016-12-01

    The aim of this work was to study the fermentation process of honey with kefir grains through a comprehensive understanding of its rheological properties, probiotic cell viability, instrumental color parameters and kinetic aspects in a batch bioreactor and during storage. The results showed that kefir grains were well adapted to bioreactor conditions, reaching high levels of cell viability (over 10 6 CFU mL -1 for total yeast and bacteria), phenolic compounds content (190 GAE/100 g) and acidification after 24 h of fermentation at 30 ℃. Colorimetric analysis showed that lightness (L*) and redness (a*) remained constant, while yellowness intensities (b*) decreased during fermentation time. After 35 days of storage, honey kefir beverage maintained its chemical characteristics and microbial viability as required to be classified as a probiotic product. The Ostwald-de-Waele (R 2  ≥ 0.98) and Herschel-Bulkley (R 2  ≥ 0.99) models can be used to predict the behavior of honey kefir beverage. The parameters analyzed in this study should be taken into account for industrial production of this novel non-dairy beverage. © The Author(s) 2016.

  9. EFFECTS OF ORAL CLEAR KEFIR PROBIOTICS ON GLYCEMIC STATUS, LIPID PEROXIDATION, ANTIOXIDATIVE PROPERTIES OF STREPTOZOTOCIN INDUCED HYPERGLYCEMIA WISTAR RATS

    Directory of Open Access Journals (Sweden)

    Judiono .

    2014-09-01

    group as a positive control (ad libitum, (4 normal animals group as a negative control (ad libitum.Blood glucose was measured by enzymatic method. Lipid peroxidation measured of MDA-TBARs by spectrophotometry. SOD and GPX Antioxidants were measured by ELISA. Catalase was measured by spectrophotometry. Probiotics Clear kefir characterization was done by microbiology identification. Data were analyzed by One Way Anova, Kruskall Walis, Duncan, Mann Whitneytest with significance level p <0.05. The result showed that clear kefir supplementation 3.6 cc / day for 30 days administration, affected on blood glucose, MDA and increased antioxidant capacity. Statistical analysis showed that there were respectively decreased of glucose (p<0.001, MDA (p<0.001. SOD antioxidant capacity was increased (<0,05, in addition GPx and Cat were also inceased(p<0,001, except in control groups. Probiotics kefir was found as many as 10(6-10(9 cfu / mL and declined to 10(5 as the decrease in pH during storage, four species of probiotics were detected, such as: Lactobacillus Sp, Sp Lactococcus and Acetobacter and Saccharomyces Sp.In conclusion, kefir supplementation significantlydecreased the blood glucose level, level of MDA and increased of antioxidants capacity. The number of probiotics declined during storage.It is interesting to identify a potential clear kefir probiotics in a pathogenesis of the β cells pancreatic repair and stability product during storage for future study. Keywords: probiotic, hyperglycemia, free radicals, lipid peroxidation, antioxidant

  10. Effect of kefir and low-dose aspirin on arterial blood pressure measurements and renal apoptosis in unhypertensive rats with 4 weeks salt diet.

    Science.gov (United States)

    Kanbak, Güngör; Uzuner, Kubilay; Kuşat Ol, Kevser; Oğlakçı, Ayşegül; Kartkaya, Kazım; Şentürk, Hakan

    2014-01-01

    Abstract We aim to study the effect of low-dose aspirin and kefir on arterial blood pressure measurements and renal apoptosis in unhypertensive rats with 4 weeks salt diet. Forty adult male Sprague-Dawley rats were divided into five groups: control, high-salt (HS) (8.0% NaCl), HS+aspirin (10 mg/kg), HS+kefir (10.0%w/v), HS+aspirin +kefir. We measured sistolic blood pressure (SBP), mean arterial pressure (MAP), diastolic pressure, pulse pressure in the rats. Cathepsin B, L, DNA fragmentation and caspase-3 activities were determined from rat kidney tissues and rats clearance of creatinine calculated. Although HS diet increased significantly SBP, MAP, diastolic pressure, pulse pressure parameters compared the control values. They were not as high as accepted hypertension levels. When compared to HS groups, kefir groups significantly decrease Cathepsin B and DNA fragmentation levels. Caspase levels were elevated slightly in other groups according to control group. While, we also found that creatinine clearance was higher in HS+kefir and HS+low-dose aspirin than HS group. Thus, using low-dose aspirin had been approximately decreased of renal function damage. Kefir decreased renal function damage playing as Angiotensin-converting enzyme inhibitor. But, low-dose aspirin together with kefir worsened rat renal function damage. Cathepsin B might play role both apoptosis and prorenin-processing enzyme. But not caspase pathway may be involved in the present HS diet induced apoptosis. In conclusion, kefir and low-dose aspirin used independently protect renal function and renal damage induced by HS diet in rats.

  11. Antibacterial Effects of a Cell-Penetrating Peptide Isolated from Kefir.

    Science.gov (United States)

    Miao, Jianyin; Guo, Haoxian; Chen, Feilong; Zhao, Lichao; He, Liping; Ou, Yangwen; Huang, Manman; Zhang, Yi; Guo, Baoyan; Cao, Yong; Huang, Qingrong

    2016-04-27

    Kefir is a traditional fermented milk beverage used throughout the world for centuries. A cell-penetrating peptide, F3, was isolated from kefir by Sephadex G-50 gel filtration, DEAE-52 ion exchange, and reverse-phase high-performance liquid chromatography. F3 was determined to be a low molecular weight peptide containing one leucine and one tyrosine with two phosphate radicals. This peptide displayed antimicrobial activity across a broad spectrum of organisms including several Gram-positive and Gram-negative bacteria as well as fungi, with minimal inhibitory concentration (MIC) values ranging from 125 to 500 μg/mL. Cellular penetration and accumulation of F3 were determined by confocal laser scanning microscopy. The peptide was able to penetrate the cellular membrane of Escherichia coli and Staphylococcus aureus. Changes in cell morphology were observed by scanning electron microscopy (SEM). The results indicate that peptide F3 may be a good candidate for use as an effective biological preservative in agriculture and the food industry.

  12. The effects of dietary kefir and low molecular weight sodium alginate on serum immune parameters, resistance against Streptococcus agalactiae and growth performance in Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Van Doan, Hien; Hoseinifar, Seyed Hossein; Tapingkae, Wanaporn; Khamtavee, Pimporn

    2017-03-01

    The present study evaluates the effects of dietary kefir and low molecular weight sodium alginate (LWMSA) (singular or combined) on non-specific immune response, disease resistance and growth performance of Nile tilapia (Oreochromis niloticus). Fish with average weight of 18.60 ± 0.04 g were supplied and randomly stocked in sixteen glass tanks (150 L) at density of 20 fish per tank. Fish were fed experimental diets as follows: 0 g kg -1 LMWSA (Control, Diet 1), 10 g kg -1 LMWSA (Diet 2), 40 g kg -1 kefir (Diet 3), and 10 g kg -1 LMWSA + 40 g kg -1 kefir (Diet 4) for 50 days. At the end of the feeding trial, serum lysozyme (SL), phagocytosis (PI), respiratory burst (RB), and alternative complement (ACH50) activities as well as growth performance were measured. Singular and combined administration of kefir and low molecular weight sodium alginate (LMWSA) significantly increased serum SL, PI, RB, and ACH50 activities compared control group (P kefir + LMWSA) (P kefir and LMWSA can be considered for improving immune response, disease resistance and growth performance of Nile tilapia. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Kefir consumption does not alter plasma lipid levels or cholesterol fractional synthesis rates relative to milk in hyperlipidemic men: a randomized controlled trial [ISRCTN10820810

    Science.gov (United States)

    St-Onge, Marie-Pierre; Farnworth, Edward R; Savard, Tony; Chabot, Denise; Mafu, Akier; Jones, Peter JH

    2002-01-01

    Background Fermented milk products have been shown to affect serum cholesterol concentrations in humans. Kefir, a fermented milk product, has been traditionally consumed for its potential health benefits but has to date not been studied for its hypocholesterolemic properties. Methods Thirteen healthy mildly hypercholesterolemic male subjects consumed a dairy supplement in randomized crossover trial for 2 periods of 4 wk each. Subjects were blinded to the dairy supplement consumed. Blood samples were collected at baseline and after 4 wk of supplementation for measurement of plasma total, low-density lipoprotein, and high-density lipoprotein cholesterol and triglyceride concentrations, as well as fatty acid profile and cholesterol synthesis rate. Fecal samples were collected at baseline and after 2 and 4 wk of supplementation for determination of fecal short chain fatty acid level and bacterial content. Results Kefir had no effect on total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol or triglyceride concentrations nor on cholesterol fractional synthesis rates after 4 wk of supplementation. No significant change on plasma fatty acid levels was observed with diet. However, both kefir and milk increased (p Kefir supplementation resulted in increased fecal bacterial content in the majority of the subjects. Conclusions Since kefir consumption did not result in lowered plasma lipid concentrations, the results of this study do not support consumption of kefir as a cholesterol-lowering agent. PMID:11825344

  14. Properties of NiO nanostructured growth using thermal dry oxidation of nickel metal thin film for hydrogen gas sensing at room temperature

    Science.gov (United States)

    Abubakar, Dauda; Ahmed, Naser M.; Mahmud, Shahrom; Algadri, Natheer A.

    2017-07-01

    A highly qualitative NiO nanostructure was synthesized using thermal dry oxidation of metallic Ni thin films on ITO/glass using the RF sputtering technique. The deposited nickel thin films were oxidized in air ambient at 550 °C inside a furnace. The structural and surface morphologies, and the electrical and gas sensing properties of the NiO nanostructure were examined. An x-ray diffraction analysis demonstrated that the NiO nanostructure has a cubic structure with orientation of the most intense peak at (2 0 0), and shows good crystalline quality. Finite-element scanning electron microscopy and energy dispersive x-ray spectroscopy results revealed O and Ni present in the treated samples, indicating a pure NiO nanostructure composition obtained with high porosity. The electrical properties of the oxidize Ni thin films showed a p-type NiO thin film semiconductor. A hydrogen gas sensing measurement was made at different operating temperatures and different gas concentrations with a detection limit of 30 ppm concentration. The sensor device shows great sensing properties with an excellent sensitivity (310%) at room temperature, which decreases with an increase in the operating temperature. Superfast response and recovery times of 6 and 0.5 s, respectively, were observed with the device at 150 °C operating temperature.

  15. Treatment Efficiency by means of a Nonthermal Plasma Combined with Heterogeneous Catalysis of Odoriferous Volatile Organic Compounds Emissions from the Thermal Drying of Landfill Leachates

    Directory of Open Access Journals (Sweden)

    Daniel Almarcha

    2014-01-01

    Full Text Available The objective of the present work was to assess the odoriferous volatile organic compounds depuration efficiency of an experimental nonthermal plasma coupled to a catalytic system used for odor abatement of real emissions from a leachate thermal drying plant installed in an urban solid waste landfill. VOC screening was performed by means of HRGC-MS analysis of samples taken at the inlet and at the outlet of the nonthermal plasma system. Odor concentration by means of dynamic olfactometry, total organic carbon, mercaptans, NH3, and H2S were also determined in order to assess the performance of the system throughout several days. Three plasma frequencies (100, 150, and 200 Hz and two catalyst temperatures (150°C and 50°C were also tested. Under conditions of maximum capacity of the treatment system, the results show VOC depuration efficiencies around 69%, with average depuration efficiencies between 44 and 95% depending on the chemical family of the substance. Compounds belonging to the following families have been detected in the samples: organic acids, alcohols, ketones, aldehydes, pyrazines, and reduced sulphur compounds, among others. Average total organic carbon removal efficiency was 88%, while NH3 and H2S removal efficiencies were 88% and 87%, respectively, and odor concentration abatement was 78%.

  16. Symbiosis between microorganisms from kombucha and kefir: Potential significance to the enhancement of kombucha function.

    Science.gov (United States)

    Yang, Zhiwei; Zhou, Feng; Ji, Baoping; Li, Bo; Luo, Yangchao; Yang, Li; Li, Tao

    2010-01-01

    Gluconacetobacter sp. A4 (G. sp. A4), which had strong ability to produce d-saccharic acid 1, 4 lactone (DSL), was the key functional bacteria isolated from the kombucha preserved. This paper investigated the interaction between G. sp. A4 and ten different strains of lactic acid bacteria (LAB) obtained from kefir. The result suggested that the LAB promoted DSL production of G. sp. A4 to different extents, ranging from 4.86% to 86.70%. Symbiosis between G. sp. A4 and LAB was studied. LAB's metabolites, xylitol, and acetic acid, were utilized by G. sp. A4, and it promoted the growth of G. sp. A4 and yield of DSL. Therefore, in developing starter cultures for kombucha fermentation process, a mixed flora of LAB and G. sp. A4 would be the optimal combination.

  17. Fine structure of Tibetan kefir grains and their yeast distribution, diversity, and shift.

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    Man Lu

    Full Text Available Tibetan kefir grains (TKGs, a kind of natural starter for fermented milk in Tibet, China, host various microorganisms of lactic acid bacteria, yeasts, and occasionally acetic acid bacteria in a polysaccharide/protein matrix. In the present study, the fine structure of TKGs was studied to shed light on this unusual symbiosis with stereomicroscopy and thin sections. The results reveal that TKGs consist of numerous small grain units, which are characterized by a hollow globular structure with a diameter between 2.0 and 9.0 mm and a wall thickness of approximately 200 µm. A polyhedron-like net structure, formed mainly by the bacteria, was observed in the wall of the grain units, which has not been reported previously to our knowledge. Towards the inside of the grain unit, the polyhedron-like net structures became gradually larger in diameter and fewer in number. Such fine structures may play a crucial role in the stability of the grains. Subsequently, the distribution, diversity, and shift of yeasts in TKGs were investigated based on thin section, scanning electron microscopy, cloning and sequencing of D1/D2 of the 26S rRNA gene, real-time quantitative PCR, and in situ hybridization with specific fluorescence-labeled oligonucleotide probes. These show that (i yeasts appear to localize on the outer surface of the grains and grow normally together to form colonies embedded in the bacterial community; (ii the diversity of yeasts is relatively low on genus level with three dominant species--Saccharomyces cerevisiae, Kluyveromyces marxianus, and Yarrowia lipolytica; (iii S. cerevisiae is the stable predominant yeast species, while the composition of Kluyveromyces and Yarrowia are subject to change over time. Our results indicate that TKGs are relatively stable in structure, and culture conditions to some extent shape the microbial community and interaction in kefir grains. These findings pave the way for further study of the specific symbiotic

  18. Fine Structure of Tibetan Kefir Grains and Their Yeast Distribution, Diversity, and Shift

    Science.gov (United States)

    Lu, Man; Wang, Xingxing; Sun, Guowei; Qin, Bing; Xiao, Jinzhou; Yan, Shuling; Pan, Yingjie; Wang, Yongjie

    2014-01-01

    Tibetan kefir grains (TKGs), a kind of natural starter for fermented milk in Tibet, China, host various microorganisms of lactic acid bacteria, yeasts, and occasionally acetic acid bacteria in a polysaccharide/protein matrix. In the present study, the fine structure of TKGs was studied to shed light on this unusual symbiosis with stereomicroscopy and thin sections. The results reveal that TKGs consist of numerous small grain units, which are characterized by a hollow globular structure with a diameter between 2.0 and 9.0 mm and a wall thickness of approximately 200 µm. A polyhedron-like net structure, formed mainly by the bacteria, was observed in the wall of the grain units, which has not been reported previously to our knowledge. Towards the inside of the grain unit, the polyhedron-like net structures became gradually larger in diameter and fewer in number. Such fine structures may play a crucial role in the stability of the grains. Subsequently, the distribution, diversity, and shift of yeasts in TKGs were investigated based on thin section, scanning electron microscopy, cloning and sequencing of D1/D2 of the 26S rRNA gene, real-time quantitative PCR, and in situ hybridization with specific fluorescence-labeled oligonucleotide probes. These show that (i) yeasts appear to localize on the outer surface of the grains and grow normally together to form colonies embedded in the bacterial community; (ii) the diversity of yeasts is relatively low on genus level with three dominant species – Saccharomyces cerevisiae, Kluyveromyces marxianus, and Yarrowia lipolytica; (iii) S. cerevisiae is the stable predominant yeast species, while the composition of Kluyveromyces and Yarrowia are subject to change over time. Our results indicate that TKGs are relatively stable in structure, and culture conditions to some extent shape the microbial community and interaction in kefir grains. These findings pave the way for further study of the specific symbiotic associations between S

  19. ENVIRONMENTAL ASPECTS OF THE INTENSIFICATION CONVECTIVE DRYING

    Directory of Open Access Journals (Sweden)

    A. M. Gavrilenkov

    2012-01-01

    Full Text Available Identified and analyzed the relationship of the intensity convective drying and air pollution emissions of heat. The ways to reduce the thermal pollution of the atmosphere at convective drying.

  20. Effects of Starter Culture and Storage Temperature on Functional, Microbial and Sensory Characteristics of Kefir during Storage

    Directory of Open Access Journals (Sweden)

    Tayyebeh Sarlak

    2017-03-01

    Full Text Available The aim of this study was to investigate the effects of starters and storage temperature (4 ºC, 25 ºC on microbiological and physicochemical properties, volatile compounds and sensory evaluation of kefir. Kefirs produced by KFA and Chr. Hansen starters were stored at 4 ºC and 25 ºC for 40 days. pH and acidity at 4 ºC did not change (p ≥ 0.05, while at 25 ºC pH and total solid decreased as well as acidity. Concentrations of acetaldehyde and ethanol increased (p < 0.05. No significant differences (p ≥ 0.05 were observed in protein and non-protein-nitrogen for both samples. Sensory evaluation revealed that storage did not affect texture and color of samples at 4 ºC. Kefir produced by Chr. Hansen starter stored at 4 ºC had the highest acceptability until 40-day storage and was preferred by the panelists.

  1. Kefir consumption does not alter plasma lipid levels or cholesterol fractional synthesis rates relative to milk in hyperlipidemic men: a randomized controlled trial [ISRCTN10820810

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    Mafu Akier

    2002-01-01

    Full Text Available Abstract Background Fermented milk products have been shown to affect serum cholesterol concentrations in humans. Kefir, a fermented milk product, has been traditionally consumed for its potential health benefits but has to date not been studied for its hypocholesterolemic properties. Methods Thirteen healthy mildly hypercholesterolemic male subjects consumed a dairy supplement in randomized crossover trial for 2 periods of 4 wk each. Subjects were blinded to the dairy supplement consumed. Blood samples were collected at baseline and after 4 wk of supplementation for measurement of plasma total, low-density lipoprotein, and high-density lipoprotein cholesterol and triglyceride concentrations, as well as fatty acid profile and cholesterol synthesis rate. Fecal samples were collected at baseline and after 2 and 4 wk of supplementation for determination of fecal short chain fatty acid level and bacterial content. Results Kefir had no effect on total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol or triglyceride concentrations nor on cholesterol fractional synthesis rates after 4 wk of supplementation. No significant change on plasma fatty acid levels was observed with diet. However, both kefir and milk increased (p Conclusions Since kefir consumption did not result in lowered plasma lipid concentrations, the results of this study do not support consumption of kefir as a cholesterol-lowering agent.

  2. The effects of kefir, koumiss, yogurt and commercial probiotic formulations on PPARα and PPAR-β/δ expressions in mouse kidney.

    Science.gov (United States)

    Sari, E K; Bakir, B; Aydin, B D; Sozmen, M

    2014-05-01

    Commercial probiotic capsules that contain probiotic bacteria, kefir, koumiss and yogurt contain beneficial microorganisms that affect cholesterol levels and immune response, and are used for treatment of some diseases. We investigated using immunohistochemistry the effects of kefir, koumiss, yogurt and a commercial probiotic formulation on the expression levels of peroxisome proliferator-activated receptor-α (PPARα) and peroxisome proliferator-activated receptor-β/δ (PPAR-β/δ), which are members of the nuclear steroid hormone receptor superfamily in mouse kidney. Mice were assigned to five groups: group 1, commercial probiotic capsules; group 2, kefir; group 3, koumiss; group 4, yogurt; group 5, control. After oral administration for 15 days, body weights were recorded and kidney tissue samples were obtained. Hematoxylin & eosin staining and the streptavidin-biotin peroxidase complex (ABC) method were applied to tissue sections to examine histology and to determine the localization of PPARα and PPAR-β/δ in the kidneys. We found that the weights of the mice in the kefir, koumiss, yogurt and commercial probiotic capsules groups were increased compared to controls. No differences in kidney histology were observed in any of the experimental groups. Kefir, koumiss, yogurt and the commercial probiotic preparation increased PPARα and PPAR-β/δ expressions.

  3. Thermal insulation

    International Nuclear Information System (INIS)

    Pinsky, G.P.

    1977-01-01

    Thermal insulation for vessels and piping within the reactor containment area of nuclear power plants is disclosed. The thermal insulation of this invention can be readily removed and replaced from the vessels and piping for inservice inspection, can withstand repeated wettings and dryings, and can resist high temperatures for long periods of time. 4 claims, 3 figures

  4. Níveis séricos de cortisol basal em ratos sob tratamento oral com kefir

    Directory of Open Access Journals (Sweden)

    Bárbara de Oliveira Prado

    2013-08-01

    Full Text Available A via de metabolismo do kefir ainda é desconhecida em muitas funções, pois há poucos estudos que a evidenciam. Assim a proposta do presente estudo é avaliar o efeito do kefir sobre os níveis séricos de cortisol basal. Um Estudo experimental em que foram utilizados 60 ratos, machos, wistar, peso de 180±30g, sendo 20 animais de experimento por 07, 14 e 21dias, divididos em Kefir 20g/200ml (GK; Dexametasona 0,125mg/kg (GD; Ranitidina 0,85mg/kg (GR; Omeprazol 0,68mg/kg (GO; Controle água ad libitum (GCO. Os resultados foram avaliados pelo Software BioEstat 5.0, e para verificação do nível de significância (α<5% usou-se a ANOVA com o teste Tukey-kramer e Bartlett’s test. Os resultados obtidos revelaram que o cortisol basal (µg/dL do sangue de 60 ratos (Rattus norvegicus submetidos ao tratamento, com D7 (P<0.05, evidenciou no GR uma média representativa sobre os demais grupos com 2.2075 μg/dl, e desvio padrão (SD de 0.4329 μg/dl. Já em D14, as alterações evidenciadas foram relativamente mínimas e pouco representativas, com D21 quando relacionado o GO e GR (P<0.01, ao que tange a relação entre o GK e o GD apresentou diferenças significativas (P< 0,001. A média no GK foi de 3,4 μg/dl com um SD de 0,3238 μg/dl sobre os demais grupos experimentais, o GD apresentou níveis muito baixos de cortisol com 0,0275μg/dl e o SD de 0,009574 μg/dl. Conclui-se que o Kefir, quando consumido em doses contínuas e diariamente, repercutiu na elevação dos níveis séricos de cortisol. Não foi possível estabelecer a via de mecanismo que tenha contribuído para tal, entretanto, esse aumento ocorreu sem que os animais sofressem qualquer tipo de dano, ou seja, os animais submetidos ao tratamento com kefir mostraram-se mais vistosos, pelagem firme e com brilho, esboçando aspecto saudável.

  5. Use of Raman spectroscopy and chemometrics for the quantification of metal ions attached to Lactobacillus kefir.

    Science.gov (United States)

    Gerbino, E; Mobili, P; Tymczyszyn, E E; Frausto-Reyes, C; Araujo-Andrade, C; Gómez-Zavaglia, A

    2012-02-01

    To set-up an experimental and analytical methodology to evaluate the feasibility of developing simple, accurate and quantitative models based on Raman spectroscopy and multivariate analysis for the quantification of metal ions adsorbed to the bacterial surface of Lactobacillus kefir. One millilitre cultures from two strains of Lact. kefir in the stationary phase were harvested and washed twice with ultra pure water. The bacterial pellets were resuspended into 1 ml solutions of Pb(+2), Cd(+2) or Ni(+2) ranging from 0 to 0·9 mmol l(-1). The suspensions were further incubated for 1 h at 30°C at pH 5·5. After centrifugation, the pellets were kept to register the Raman spectra and the supernatants were used for the analytical determination of Pb(+2) , Cd(+2) and Ni(+2). Micro-organisms nontreated with metal ions were used as controls. Principal component analysis (PCA) was performed over the preprocessed Raman spectra to evaluate whether the clusters obtained could be correlated with the concentration of metal ions attached to the bacterial biomass. After that, partial least squares (PLS) models were calibrated with the aim of quantifying the metal ions adsorbed to the bacterial surface. According to the analytical determinations, the maximum binding capacity of all the metals (q(max)) attained values that are comparable with those observed for other lactic acid bacteria (ca. 0·200 mmol g(-1)). The spectral analysis revealed that the main functional groups involved in the bacteria/metal interaction are carboxylates, phosphates and polysaccharides. In PCA, the first two principal components explain more than 72% variance of the spectral data set contained in the data structure, allowing a clear discrimination among samples of different concentrations. Based on this information and using as reference the results obtained by analytical methods, PLS prediction models were successfully defined for the quantification of Pb(+2), Cd(+2) and Ni(+2) attached to the bacterial

  6. Goat Milk Kefir Supplemented with Porang Glucomannan Improves Lipid Profile and Haematological Parameter in Rat Fed High Fat and High Fructose Diet

    Directory of Open Access Journals (Sweden)

    Nurliyani

    2018-03-01

    Full Text Available Background and Aims: Diet with a high fat and high sugar is associated with an increased incindence of the metabolic syndrome. Kefir has been known as a natural probiotic, while glucomannan from porang (Amorphophallus oncophyllus tuber was demonstrated as prebiotic in vivo. Probiotics and prebiotics can be used adjuvant nutritional therapy for metabolic syndrome. The aim of this study was to evaluate the effect of goat milk kefir supplemented with porang glucomannan on the lipid profile and haematological parameters in rats fed with a high-fat/high-fructose (HFHF diet.

  7. Study thermal characteristics of millet grain, dried in the machine with the swirling flow of the coolant and the microwave energy supply

    Directory of Open Access Journals (Sweden)

    S. T. Antipov

    2016-01-01

    Full Text Available The article discusses the problems of determining the thermal characteristics of millet. The choice of the research object. The paper presents the principle of operation of the plant and the parameters of the standard, organic glass for measurements. Method was to study millet grains and organic glass, which are brought into contact on a common plane. The heater is brought into contact with the product and passed the constant heat flow, which passed through a layer of millet grain at different speeds. As a result, the temperature in the contact plane of the changed and recorded on the chart of the potentiometer in the form of the curve, by which you can determine the time and temperature change. The thermal diffusivity and thermal conductivity determined by empirical formulas obtained by solving a system of differential equations, made up for the system of two bodies, one of which includes the unknown thermal characteristics. Test two bodies in contact on a common plane, resulting in mathematical physics principles constitute two differential equations with uniform initial and boundary conditions of the first kind, due to the parameters of ongoing experience. It is a plot of thermal performance of the temperature and humidity. Revealed linear dependence of the physical thermal characteristics, showing that with increasing temperature the thermal diffusivity value decreases, and the thermal conductivity and specific heat capacity are increasing character. Revealed the equations describing the thermal characteristics of millet grain with a humidity in the range of 13.6–35.1% and the temperature range 293–373 K.

  8. Atividade antiinflamatória de carboidrato produzido por fermentação aquosa de grãos de quefir Anti-inflammatory activity of carbohydrate produced from aqueous fermentation of kefir

    Directory of Open Access Journals (Sweden)

    Maria E. C. Moreira

    2008-01-01

    Full Text Available Kefir, a symbiont microorganism suspension, presents benefic effects to health. Some kefir grains were cultivated in brown sugar, allowing to isolate a substance named CSQ. This was evaluated on a biologic essay of mouse foot edema, presenting an inhibitory activity of 30+4 % against carrageenan after the stimulus. It was observed that a cultivation mean containing sucrose, and not the milky mean, lead to the production of different sugar polymeric chains of kefir. The results in vivo suggest that the CSQ exerted an anti-inflammatory activity.

  9. Aceitação e perfil sensorial das cachaças produzidas com Kefir e Saccharomyces cerevisae Acceptance and sensory profile of cachaça produced using Kefir and Saccharomyces cerevisae

    Directory of Open Access Journals (Sweden)

    Anita Saraiva Dornelles

    2009-09-01

    Full Text Available A levedura Saccharomyces cerevisae é o microrganismo mais utilizado industrialmente nas destilarias, mas outros microrganismos também são capazes de produzir etanol utilizando matérias-primas açucaradas como substrato. O objetivo deste trabalho foi determinar o perfil sensorial e a aceitação da aguardente de cana produzida através da fermentação alcoólica com grânulos de Kefir, comparando-a ao produto obtido tradicionalmente. Pelo método de ADQ, 8 provadores treinados avaliaram os seguintes descritores: aroma alcoólico e de cachaça, sabor alcoólico e de cachaça, gosto amargo e ardência. O teste de aceitação foi realizado por 57 consumidores de aguardente, utilizando-se uma escala hedônica estruturada de nove pontos para avaliar a aceitação do aroma e a aceitação global. A cachaça com Kefir apresentou maior intensidade de aroma alcoólico e gosto amargo, obtendo menor aceitação global que a cachaça de levedura. Dessa forma, o produto foi considerado de grande potencial visto que apresentou satisfatório percentual de aprovação entre os consumidores.Saccharomyces cerevisae is the main industrially used yeast to produce sugar cane spirits (cachaça. However, other microorganisms are able to produce ethanol using sugar as substrate. This work aimed at determining the sensory profile of cachaça produced through the alcoholic fermentation with Kefir's granules and its acceptance. The acceptance analysis was performed by 57 consumers using a 9 point structured hedonic scale to evaluate the aroma and the general acceptance of the product. The QDA method, with 8 trained tasters, was used to evaluate the following product descriptors: alcoholic aroma, alcoholic flavor, and burning and bitter taste. The evaluated samples did not presented statistical differences (p < 0.05 among each other regarding the aroma acceptance. However, the cachaça produced using bakery yeast presented higher acceptance scores. On the other hand

  10. Characterization of dextransucrase from Leuconostoc mesenteroides T3, water kefir grains isolate

    Directory of Open Access Journals (Sweden)

    Miljković Miona G.

    2017-01-01

    Full Text Available The production of dextransucrase (DS by Leuconostoc mesenteroides T3, novel isolate from water kefir grain, was studied and optimized. Bacterial supernatant reached activity of 3.1 U/ml when the culture was grown at 23 C and under static culture condition using classical Tsuchiya medium for DS production. The increase of sucrose concentration to 7% led to an increase of DS activity by 52% compared to the control. Medium with 2% beef extract and 1% yeast extract resulted in 4.52 U/ml, which was 47% higher than in the control (with 2% yeast extract. Finally, the increase of K2HPO4 concentration from 2 to 3% resulted in the increased enzyme activity by 28%. Enzyme purified by polyethylene glycol 400 fractionation displayed maximum activity at 30°C and pH 5.4. Zymogram analysis confirmed the presence of DS of approximately 180 kDa. The addition of divalent cations Ca2+, Mg2+, Fe2+ and Co2+ led to a minor increase of DS activity, while the addition of Mn2+ was the most prominent with 73% increase. These findings classify dextransucrase from Leuconostoc mesenteroides T3 as promising candidate for production of dextran, which has numerous applications in various industries. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR 31035

  11. FTIR spectroscopy structural analysis of the interaction between Lactobacillus kefir S-layers and metal ions

    Science.gov (United States)

    Gerbino, E.; Mobili, P.; Tymczyszyn, E.; Fausto, R.; Gómez-Zavaglia, A.

    2011-02-01

    FTIR spectroscopy was used to structurally characterize the interaction of S-layer proteins extracted from two strains of Lactobacillus kefir (the aggregating CIDCA 8348 and the non-aggregating JCM 5818) with metal ions (Cd +2, Zn +2, Pb +2 and Ni +2). The infrared spectra indicate that the metal/protein interaction occurs mainly through the carboxylate groups of the side chains of Asp and Glut residues, with some contribution of the NH groups belonging to the peptide backbone. The frequency separation between the νCOO - anti-symmetric and symmetric stretching vibrations in the spectra of the S-layers in presence of the metal ions was found to be ca. 190 cm -1 for S-layer CIDCA 8348 and ca. 170 cm -1 for JCM 5818, denoting an unidentate coordination in both cases. Changes in the secondary structures of the S-layers induced by the interaction with the metal ions were also noticed: a general trend to increase the amount of β-sheet structures and to reduce the amount of α-helices was observed. These changes allow the proteins to adjust their structure to the presence of the metal ions at minimum energy expense, and accordingly, these adjustments were found to be more important for the bigger ions.

  12. Honey Addition in Kefir Whey Drink in Term of Organoleptic Quality, Colour, and Turbidity

    Directory of Open Access Journals (Sweden)

    Firman Jaya

    2017-07-01

    Full Text Available The objective of this research was to determine the optimum honey addition on kefir whey drink based on organoleptic quality (colour, aroma, taste, colour test, and turbidity. The method used in this research was experiment with Completely Randomized Design (CDR by used 4 treatments and 4 replications. The treatments were P0 = without the honey added, P1=added by 20% honey, P2 = added by 30% honey and P3 = added by 40% honey (v/v. The data were analyzed by Analysis of Variance (ANOVA, if there were significantly difference, the data would analyzed by Duncan’s Multiple Range Test. The results showed that honey addition gave highly difference significant (P<0.01 on organoleptic quality (colour, aroma, taste, turbidity and lightness (L*. Honey addition didn’t give significantly difference (P<0.05 on redness (a* and yellowness (b*. The conclusion of this research was the best treatment will the value is added by 40% honey with colour 3.25±0.78, aroma 3.50±1.14, taste 3.75±1.01, lightness (L 31.57±0.5, redness (b* 0.95±0.12, yellowness (b* 0.050±0.36, and turbidity 306.7±6.65 NTU

  13. IDENTIFICAÇÃO PRESUNTIVA DE LEVEDURAS DE INTERESSE BIOTECNOLÓGICO EM GRÃOS DE KEFIR

    Directory of Open Access Journals (Sweden)

    Fernanda Mincev ANTONIASSI

    2017-12-01

    Full Text Available Os grãos de Kefir são constituídos por uma matriz de polissacarídeos, ricos em micro-organismos simbióticos, gerando após a fermentação de açúcares, uma bebida probiótica que recebe o mesmo nome. A vasta população microbiana presente nestes grãos, incluindo leveduras e bactérias, oferece diversas características únicas à bebida. Estudos apontam que esta possui efeitos antitumorais, anti-inflamatórios, antimicrobiano, modulatório do sistema imune, anticolesterolêmico, dentre outros, devido as moléculas secretadas pelas células microbianas presente no microambiente dos grãos de Kefir. Diante disso, o objetivo deste estudo foi isolar e identificar, presuntivamente, leveduras presentes nos grãos de Kefir, possíveis produtoras de produtos de interesse biotecnológico. Para tanto, foram utilizados grãos da região de Bauru/SP, mantidos em fermentação em água/açúcar mascavo e em leite. Em seguida, os grãos foram triturados e semeados em ágar Sabouraud com cloranfenicol. Os isolados com características macroscópicas leveduriformes foram analisados por exame direto, prova do tubo germinativo e prova da ureia. Os dados obtidos foram comparados com atlas micológicos e chaves de identificação. No total foram isoladas seis colônias diferentes com presença de leveduras como Candida sp. e Saccharomyces sp., que possuem grande relevância para os processos biotecnológicos.

  14. Evaluating the behaviour of different thermal indices by investigating various outdoor urban environments in the hot dry city of Damascus, Syria.

    Science.gov (United States)

    Yahia, Moohammed Wasim; Johansson, Erik

    2013-07-01

    Consideration of urban microclimate and thermal comfort is an absolute neccessity in urban development, and a set of guidelines for every type of climate must be elaborated. However, to develop guidelines, thermal comfort ranges need to be defined. The aim of this study was to evaluate the behaviour of different thermal indices by investigating different thermal environments in Damascus during summer and winter. A second aim was to define the lower and upper limits of the thermal comfort range for some of these indices. The study was based on comprehensive micrometeorological measurements combined with questionnaires. It was found that the thermal conditions of different outdoor environments vary considerably. In general, Old Damascus, with its deep canyons, is more comfortable in summer than modern Damascus where there is a lack of shade. Conversely, residential areas and parks in modern Damascus are more comfortable in winter due to more solar access. The neutral temperatures of both the physiologically equivalent temperature (PET) and the outdoor standard effective temperature (OUT_SET*) were found to be lower in summer than in winter. At 80 % acceptability, the study defined the lower comfort limit in winter to 21.0 °C and the upper limit in summer to 31.3 °C for PET. For OUT_SET*, the corresponding lower and upper limits were 27.6 °C and 31.3 °C respectively. OUT_SET* showed a better correlation with the thermal sensation votes than PET. The study also highlighted the influence of culture and traditions on people's clothing as well as the influence of air conditioning on physical adaptation.

  15. Influence of drying method on the material properties of nanocellulose I: thermostability and crystallinity

    Science.gov (United States)

    Yucheng Peng; Douglas J. Gardner; Yousoo Han; Alper Kiziltas; Zhiyong Cai; Mandla A. Tshabalala

    2013-01-01

    The effect of drying method on selected material properties of nanocellulose was investigated. Samples of nanofibrillated cellulose (NFC) and cellulose nanocrystals (CNC) were each subjected to four separate drying methods: air-drying, freeze-drying, spray-drying, and supercritical-drying. The thermal stability and crystallinity of the dried nanocellulose were...

  16. Dry Etching

    DEFF Research Database (Denmark)

    Stamate, Eugen; Yeom, Geun Young

    2016-01-01

    for the higher processing rates in FPDs, high-density plasma processing tools that can handle larger-area substrate uniformly are more intensively studied especially for the dry etching of polysilicon thin films. In the case of FPD processing, the current substrate size ranges from 730 × 920 mm (fourth...... etching requirements, and advantages of dry etching over wet processing. Current status and future trends are also presented....

  17. Effects of Microbial Transglutaminase on Physicochemical, Microbial and Sensorial Properties of Kefir Produced by Using Mixture Cow’s and Soymilk

    Science.gov (United States)

    2017-01-01

    The objective of this research was to investigate the effects microbial transglutaminase (m-TGs) on the physicochemical, microbial and sensory properties of kefir produced by using mix cow and soymilk. Kefir batches were prepared using 0, 0.5, 1 and 1.5 Units m-TGs for per g of milk protein. Adding m-TGs to milk caused an increase in the pH and viscosity and caused a decrease in titratable acidity and syneresis in the kefir samples. Total bacteria, lactobacilli and streptococci counts decreased, while yeast counts increased in all the samples during storage. Alcohols and acids compounds have increased in all the samples except in the control samples, while carbonyl compounds have decreased in all the samples during storage (1-30 d). The differences in the percentage of alcohols, carbonyl compounds and acids in total volatiles on the 1st and the 30th d of storage were observed at 8.47-23.52%, 6.94-25.46% and 59.64-63.69%, respectively. The consumer evaluation of the kefir samples showed that greater levels of acceptability were found for samples which had been added 1.5 U m-TGs for per g of milk protein. PMID:28943774

  18. Latest Apple Drying Technologies: A Review

    OpenAIRE

    ÖZDEMİR, Yasin; SAYIN, Emir Olcay; KURULTAY, Şefik

    2009-01-01

    Drying is known as one of the oldest preservation methods and can be applicable to many fruits. Sun drying of apple has been known from ancient times. However, this technique is weather-dependent and has contamination problems such as dust, soil, sand particles and insects. Hot air drying of apples has low energy efficiency and requires longer drying period. The desire to eliminate these problems, prevent quality loss, and achieve fast and effective thermal processing has resulted in an incre...

  19. Kefir drink causes a significant yet similar improvement in serum lipid profile, compared with low-fat milk, in a dairy-rich diet in overweight or obese premenopausal women: A randomized controlled trial.

    Science.gov (United States)

    Fathi, Yasamin; Ghodrati, Naeimeh; Zibaeenezhad, Mohammad-Javad; Faghih, Shiva

    Controversy exists as to whether the lipid-lowering properties of kefir drink (a fermented probiotic dairy product) in animal models could be replicated in humans. To assess and compare the potential lipid-lowering effects of kefir drink with low-fat milk in a dairy-rich diet in overweight or obese premenopausal women. In this 8-week, single-center, multiarm, parallel-group, outpatient, randomized controlled trial, 75 eligible Iranian women aged 25 to 45 years were randomly allocated to kefir, milk, or control groups. Women in the control group received a weight-maintenance diet containing 2 servings/d of low-fat dairy products, whereas subjects in the milk and kefir groups received a similar diet containing 2 additional servings/d (a total of 4 servings/d) of dairy products from low-fat milk or kefir drink, respectively. At baseline and study end point, serum levels/ratios of total cholesterol (TC), low- and high-density lipoprotein cholesterol (LDLC and HDLC), triglyceride, Non-HDLC, TC/HDLC, LDLC/HDLC, and triglyceride/LDLC were measured as outcome measures. After 8 weeks, subjects in the kefir group had significantly lower serum levels/ratios of lipoproteins than those in the control group (mean between-group differences were -10.4 mg/dL, -9.7 mg/dL, -11.5 mg/dL, -0.4, and -0.3 for TC, LDLC, non-HDLC, TC/HDLC, and LDLC/HDLC, respectively; all P kefir and milk groups. Kefir drink causes a significant yet similar improvement in serum lipid profile, compared with low-fat milk, in a dairy-rich diet in overweight or obese premenopausal women. Copyright © 2016 National Lipid Association. Published by Elsevier Inc. All rights reserved.

  20. Dry cell battery poisoning

    Science.gov (United States)

    Batteries - dry cell ... Acidic dry cell batteries contain: Manganese dioxide Ammonium chloride Alkaline dry cell batteries contain: Sodium hydroxide Potassium hydroxide Lithium dioxide dry cell batteries ...

  1. Effect of starter culture and inulin addition on microbial viability, texture, and chemical characteristics of whole or skim milk Kefir

    Directory of Open Access Journals (Sweden)

    Flávia Daiana Montanuci

    2012-12-01

    Full Text Available The effect of inulin addition and starters (Kefir grains or commercial starter culture on the microbial viability, texture, and chemical characteristics of Kefir beverages prepared with whole or skim milk was evaluated during refrigerated storage. The type of starter did not influence microbial viability during the storage of the beverages, but the chemical and textural changes (decreases in pH, lactose concentration, and inulin and increased acidity, firmness, and syneresis were more pronounced in the formulations fermented with grains than those fermented with the starter culture. The addition of inulin did not influence acidity or viability of lactic acid bacteria, but in general, its effect on the survival of acetic acid bacteria, Lactococcus and yeasts, firmness, and syneresis depended on the type of milk and starter culture used. Generally, the yeast, acetic acid bacteria, and Leuconostoc counts increased or remained unchanged, while the total population of lactic acid bacteria and Lactococcus were either reduced by 1 to 2 logs or remained unchanged during storage.

  2. Saccharomyces cerevisiae from Brazilian kefir-fermented milk: An in vitro evaluation of probiotic properties.

    Science.gov (United States)

    Lima, Meire Dos Santos Falcão de; Souza, Karoline Mirella Soares de; Albuquerque, Wendell Wagner Campos; Teixeira, José António Couto; Cavalcanti, Maria Taciana Holanda; Porto, Ana Lúcia Figueiredo

    2017-09-01

    The therapeutic use of probiotics for supporting the antibiotic action against gastrointestinal disorders is a current trend and emerging applications have gained popularity because of their support for various microbiological activities in digestive processes. Microorganisms isolated from kefir with great probiotic properties, in addition to high resistance to harsh environmental conditions, have been widely researched. Administration of probiotic yeasts offers a number of advantages, when compared to bacteria, because of particular characteristics as their larger cell size. In the present study, 28 strains of Saccharomyces cerevisiae were isolated, after in vitro digestion of kefir-fermented milk, and identified by molecular based approaches. A screening was performed to determine important quality requirements for probiotics including: antagonistic and antioxidant activities, β-galactosidase synthesis, autoaggregation, surface hydrophobicity and adhesion to epithelial cells. The results showed strains: with antagonistic activity against microbial pathogens such as Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis; able to produce β-galactosidase; with antioxidant activity levels higher than 90%; with hydrophobicity activity and autoaggregation ability (evaluated by adhesion test, where all the strains presented adhesion to mice ileal epithelial cells). These findings are relevant and the strains are recommended for further in vivo studies as well as for potential therapeutic applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Microbial ecology and quality assurance in food fermentation systems. The case of kefir grains application.

    Science.gov (United States)

    Plessas, S; Alexopoulos, A; Voidarou, C; Stavropoulou, E; Bezirtzoglou, E

    2011-12-01

    Fermentation technology has become a modern method for food production the last decades as a process for enhancing product stability, safety and sensory standards. The main reason for this development is the increasing consumers' demand for safe and high quality food products. The above has led the scientific community to the thorough study for the appropriate selection of specific microorganisms with desirable properties such as bacteriocin production, and probiotic properties. The main food products produced through fermentation activity are bread, wine, beer cheese and other dairy products. The microorganisms conducting the above processes are mainly yeasts and lactic acid bacteria. The end products of carbohydrate catabolism by these microorganisms contribute not only to preservation as it was believed years ago, but also to the flavour, aroma and texture and to the increase of the nutritional quality by thereby helping determine unique product characteristics. Thus, controlling the function of specific microorganisms or the succession of microorganisms that dominate the microflora is therefore advantageous, because it can increase product quality, functionality and value. Throughout the process of the discovery of microbiological diversity in various fermented food systems, the development of starter culture technology has gained more scientific attention, and it could be used for the control of the manufacturing operation, and management of product quality. In the frame of this review the presentation of the quality enhancement of most consumed fermented food products around the world is attempted and the new trends in production of fermented food products, such as bread is discussed. The review is focused in kefir grains application in bread production. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. Isolation and Characterization of Exopolysaccharide-Producing Lactobacillus plantarum SKT109 from Tibet Kefir

    Directory of Open Access Journals (Sweden)

    Wang Ji

    2015-12-01

    Full Text Available Lactobacillus plantarum SKT109 was isolated and identified from Tibet Kefir, and the exopolysaccharride (EPS-producing properties of the strain were evaluated. Growth of strain SKT109 in a semi-defined medium at 37°C increased the viscosity of the medium, corresponding to production of an EPS (58.66 mg/L. The EPS was isolated and purified, and it was shown to consist of fructose and glucose in an approximate molar ratio of 3:1, with an average molecular weight of 2.1×106 Da. The aqueous solution of EPS at 1% (w/v exhibited shear thinning behavior. Microstructural studies of the EPS demonstrated a highly compact structure with a smooth surface, facilitating formation of film by the polymer; the EPS was composed of many different sizes of spherical lumps with tendency to form molecular aggregates. Studies on the milk fermentation characteristics of L. plantarum SKT109 showed that the strain survived well in fermented milk with counts about 8.0 log cfu/g during 21 days of storage at 4°C. The use of the EPS-producing strain improved the rheology of the fermented milk without causing post-acidification during storage. Particularly, L. plantarum SKT109 improved the fermented milk flavor by increasing the concentration of characteristic flavor compounds and eliminating those with dis gusting flavors. The results of the present study indicated that EPS-producing L. plantarum SKT109 could serve as a promising candidate for further exploitation in fermented foods.

  5. Effects of Lactobacillus kefiranofaciens M1 isolated from kefir grains on germ-free mice.

    Directory of Open Access Journals (Sweden)

    Yen-Po Chen

    Full Text Available Lactobacillus kefiranofaciens M1 is a novel probiotic strain that was isolated from kefir grains. Previously, we have demonstrated the immunoregulatory, anti-allergic, anti-asthmatic and anti-colitis abilities of L. kefiranofaciens M1 in a number of in-vitro and in-vivo experiments. However, whether the effects of L. kefiranofaciens M1 are elicited directly on the host or act by regulating the host's microbiota remains unknown. A number of studies have used germ-free or gnotobiotic animals to investigate the relationship between probiotics and colitis; therefore the aim of this study was to investigate the effects of L. kefiranofaciens M1 on germ-free mice. Such an approach should help in determining the direct effects of L. kefiranofaciens M1 on the host itself. Four-week-old female germ-free mice were inoculated intragastrically with 2×10(8 CFU/mouse L. kefiranofaciens M1 once or at 2-day intervals for 14 days. Bacterial colonization, the Th1/Th2 cytokine profile of the mice's splenocytes and the anti-colitis effect of L. kefiranofaciens M1 were investigated. The strongest response in terms of splenic Th1 cytokine IFN-γ and IL-12 production upon TLR activation was detected in the continuous treatment group when comparing to the single inoculation group and the germ-free control. In addition, continuous inoculation with L. kefiranofaciens M1 was found to ameliorate the symptoms of DSS-induced colitis in germ-free mice. However, L. kefiranofaciens M1 failed to colonize the host. Thus it would seem that L. kefiranofaciens M1 is likely to act directly on the host and not be involved in microbiota regulation.

  6. Physicochemical, microbiological and sensory profiles of fermented milk containing probiotic strains isolated from kefir.

    Science.gov (United States)

    Kakisu, Emiliano; Irigoyen, Aurora; Torre, Paloma; De Antoni, Graciela L; Abraham, Analía G

    2011-11-01

    A two-strain starter culture containing Lactobacillus plantarum CIDCA 83114, a potential probiotic strain isolated from kefir grains, and Streptococcus thermophilus CIDCA 321 was tested for the preparation of a fermented milk product. Kluyveromyces marxianus CIDCA 8154, a yeast with immunomodulatory properties was included to formulate a three-strain starter culture. Supernatants of enterohaemorragic Escherichia coli, shiga-toxin-producing strain, along with a two-strain or a three-strain starter culture were included in the medium of Vero-cell surface cultures. The results demonstrated that these combinations of microorganisms antagonize the cytopathic action of shiga toxins. The cell concentration of Lb. plantarum did not decrease during fermentation, indicating that the viability of this strain was not affected by low pH, nor did the number of viable bacteria change during 21 days of storage in either fermented products. The number of viable yeasts increases during fermentation and storage. Trained assessors analyzed the general acceptability of fresh fermented milks and considered both acceptable. The milk fermented with the two-strain starter culture was considered acceptable after two week of storage, while the product fermented with the three-strain starter culture remained acceptable for less than one week. The main changes in sensory attributes detected by the trained panel were in sour taste, milky taste and also in fermented attributes. The correlation between different sensory attributes and acceptability indicated that the panel was positively influenced by milky attributes (taste, odour, and flavour) as well as the intensity of flavour. In conclusion, the two-strain starter culture would be the more promising alternative for inclusion of that potential probiotic lactobacillus in a fermented milk product.

  7. Role of S-layer proteins in the biosorption capacity of lead by Lactobacillus kefir.

    Science.gov (United States)

    Gerbino, Esteban; Carasi, Paula; Araujo-Andrade, Cuauhtémoc; Tymczyszyn, E Elizabeth; Gómez-Zavaglia, Andrea

    2015-04-01

    The role of S-layer proteins (SLP) on the Pb(2+) sequestrant capacity by Lactobacillus kefir CIDCA 8348 and JCM 5818 was investigated. Cultures in the stationary phase were treated with proteinase K. A dot blot assay was carried out to assess the removal of SLP. Strains with and without SLP were exposed to 0-0.5 mM Pb(NO3)2. The maximum binding capacity (q max ) and the affinity coefficient (b) were calculated using the Langmuir equation. The structural effect of Pb(2+) on microorganisms with and without SLP was determined using Raman spectroscopy. The bacterial interaction with Pb(2+) led to a broadening in the phosphate bands (1,300-1,200 cm(-1) region) and strong alterations on amide and carboxylate-related bands (νCOO(-) as and νCOO(-) s). Microorganisms without SLP removed higher percentages of Pb(2+) and had higher q max than those bearing SLP. Isolated SLP had much lower q max and also removed lower percentages of Pb(2+) than the corresponding whole microorganisms. The hydrofobicity of both strains dramatically dropped when removing SLP. When bearing SLP, strains do not expose a large amount of charged groups on their surfaces, thus making less efficient the Pb(2+) removal. On the contrary, the extremely low hydrofobicity of microorganisms without SLP (and consequently, their higher capacity to remove Pb(2+)) can be explained on the basis of a greater exposure of charged chemical groups for the interaction with Pb(2+). The viability of bacteria without SLP was not significantly lower than that of bacteria bearing SLP. However, microorganisms without SLP were more prone to the detrimental effect of Pb(2+), thus suggesting that SLP acts as a protective rather than as a sequestrant layer.

  8. Dynamics of acoustic-convective drying of sunflower cake

    Science.gov (United States)

    Zhilin, A. A.

    2017-10-01

    The dynamics of drying sunflower cake by a new acoustic-convective method has been studied. Unlike the conventional (thermal-convective) method, the proposed method allows moisture to be extracted from porous materials without applying heat to the sample to be dried. Kinetic curves of drying by the thermal-convective and acoustic-convective methods were obtained and analyzed. The advantages of the acoustic-convective extraction of moisture over the thermal-convective method are discussed. The relaxation times of drying were determined for both drying methods. An intermittent drying mode which improves the efficiency of acoustic-convective extraction of moisture is considered.

  9. Thermally dried ink-jet process for 6,13-bis(triisopropylsilylethynyl)-pentacene for high mobility and high uniformity on a large area substrate

    Science.gov (United States)

    Ryu, Gi Seong; Lee, Myung Won; Jeong, Seung Hyeon; Song, Chung Kun

    2012-01-01

    In this study we developed a simple ink-jet process for 6,13-bis(triisopropylsilylethynyl)-pentacene (TIPS-pentacene), which is known as a high-mobility soluble organic semiconductor, to achieve relatively high-mobility and high-uniformity performance for large-area applications. We analyzed the behavior of fluorescent particles in droplets and applied the results to determining a method of controlling the behavior of TIPS-pentacene molecules. The grain morphology of TIPS-pentacene varied depending on the temperature applied to the droplets during drying. We were able to obtain large and uniform grains at 46 degrees C without any "coffee stain". The process was applied to a large-size organic thin-film transistor (OTFT) backplane for an electrophoretic display panel containing 192 x 150 pixels on a 6-in.-sized substrate. The average of mobilities of 36 OTFTs, which were taken from different locations of the backplane, was 0.44 +/- 0.08 cm2.V-1.s-1, with a small deviation of 20%, over a 6-in.-size area comprising 28,800 OTFTs. This process providing high mobility and high uniformity can be achieved by simply maintaining the whole area of the substrate at a specific temperature (46 degrees C in this case) during drying of the droplets.

  10. Dry Cleaning

    OpenAIRE

    Shirley, Lindsey; Weller, Chanae

    2010-01-01

    Despite its name, commercial dry cleaning is not actually a “dry” process. Clothes are immersed in a solvent, most commonly perchlorethylene (perc), instead of in water. Perc or other similar solvents are effective in the removal of oil and grease-based stains without damaging or shrinking sensitive fabrics, unlike a regular detergents and fabric softeners.

  11. Dry storage

    International Nuclear Information System (INIS)

    Arnott, Don.

    1985-01-01

    The environmental movement has consistently argued against disposal of nuclear waste. Reasons include its irretrievability in the event of leakage, the implication that reprocessing will continue and the legitimacy attached to an expanding nuclear programme. But there is an alternative. The author here sets out the background and a possible future direction of a campaign based on a call for dry storage. (author)

  12. Efecto del secado térmico y el tratamiento alcalino en las características microbiológicas y químicas de biosólidos de plantas de tratamiento de aguas residuales domésticas Effect of thermal drying and alkaline treatment on the microbiological and chemical characteristics of biosolids from domestic wastewater treatment plants

    Directory of Open Access Journals (Sweden)

    Jorge Silva-Leal

    2013-01-01

    Full Text Available We evaluated the effect of thermal drying (60 to 75 ºC and times from 0 to 12.58 h and alkaline treatment (Ca(OH2 and CaO at doses from 8 to 10%. on the microbiological and chemical characteristics of biosolids from the Cañaveralejo WWTP. The results showed that in thermal drying all temperatures studied were sufficient to achieve the sanitation of biosolids. In the alkaline treatment the two types of lime showed the total elimination of fecal coliforms, E. coli and helminth eggs, however, the process of alkalization of biosolids had significant influences on organic carbon and calcium.

  13. Kefir peptides prevent high-fructose corn syrup-induced non-alcoholic fatty liver disease in a murine model by modulation of inflammation and the JAK2 signaling pathway.

    Science.gov (United States)

    Chen, H L; Tsai, T C; Tsai, Y C; Liao, J W; Yen, C C; Chen, C M

    2016-12-12

    In recent years, people have changed their eating habits, and high-fructose-containing bubble tea has become very popular. High-fructose intake has been suggested to be a key factor that induces non-alcoholic fatty liver disease (NAFLD). Kefir, a fermented milk product composed of microbial symbionts, has demonstrated numerous biological activities, including antibacterial, antioxidant and immunostimulating effects. The present study aims to evaluate the effects of kefir peptides on high-fructose-induced hepatic steatosis and the possible molecular mechanism. An animal model of 30% high-fructose-induced NAFLD in C57BL/6J mice was established. The experiment is divided into the following six groups: (1) normal: H 2 O drinking water; (2) mock: H 2 O+30% fructose; (3) KL: low-dose kefir peptides (50 mg kg -1 )+30% fructose; (4) KM: medium-dose kefir peptides (100 mg kg -1 )+30% fructose; (5) KH: high-dose kefir peptides (150 mg kg -1 )+30% fructose; and (6) CFM: commercial fermented milk (100 mg kg -1 )+30% fructose. The results show that kefir peptides improve fatty liver syndrome by decreasing body weight, serum alanine aminotransferase, triglycerides, insulin and hepatic triglycerides, cholesterol, and free fatty acids as well as the inflammatory cytokines (TNF-α, IL-6 and IL-1β) that had been elevated in fructose-induced NAFLD mice. In addition, kefir peptides markedly increased phosphorylation of AMPK to downregulate its targeted enzymes, ACC (acetyl-CoA carboxylase) and SREBP-1c (sterol regulatory element-binding protein 1), and inhibited de novo lipogenesis. Furthermore, kefir peptides activated JAK2 to stimulate STAT3 phosphorylation, which can translocate to the nucleus, and upregulated several genes, including the CPT1 (carnitine palmitoyltransferase-1) involved in fatty acid oxidation. Our data have demonstrated that kefir peptides can improve the symptoms of NAFLD, including body weight, energy intake, inflammatory reaction and the

  14. Dry Mouth or Xerostomia

    Science.gov (United States)

    ... Side Effects > Dry Mouth or Xerostomia Request Permissions Dry Mouth or Xerostomia Approved by the Cancer.Net Editorial Board , 05/ ... with a dry mouth. Signs and symptoms of dry mouth The signs and symptoms of dry mouth include ...

  15. dry sausage

    African Journals Online (AJOL)

    AJB SERVER

    2006-08-17

    Aug 17, 2006 ... fermentation, desired pH of fermentation (4.9 - 5.0) was achieved after 24 h fermentation, at temperature 30 and. 35°C, which is the desired mesophilic condition for lactic bacterial growth. With the progress of drying, the decrease in pH due to formation of lactic acid was directly proportional to the increase ...

  16. Studies into the Stability of 3-O-Glycosylated and 3,5-O-Diglycosylated Anthocyanins in Differently Purified Liquid and Dried Maqui (Aristotelia chilensis (Mol.) Stuntz) Preparations during Storage and Thermal Treatment.

    Science.gov (United States)

    Brauch, Johanna E; Kroner, Mareike; Schweiggert, Ralf M; Carle, Reinhold

    2015-10-07

    Anthocyanin stabilities in diluted and differently purified maqui preparations were assessed during storage and thermal treatment at different pH values. By sequentially depleting the matrix, the influence of polar low-molecular-weight matrix constituents and non-anthocyanin phenolics was shown to be negligible. In contrast, pH substantially affected thermal stabilities of differently glycosylated cyanidin and delphinidin derivatives. At pH 3.6, half-lives of 3-O-glycosides were substantially shorter than those of respective 3,5-O-diglycosides. However, at pH 2.2, an inverse stability behavior was observed. Findings were corroborated using isolated pigments. Upon heating, cyanidin derivatives were more stable than their respective delphinidins, but their stability was similar during storage. Anthocyanins in liquid samples were more stable when stored at 4 °C as compared to 20 °C, whereas those in dried powders revealed maximum stability throughout storage. The study contains a detailed discussion and mechanistic hypothesis for the above-mentioned findings, providing insights relevant for food applications of maqui anthocyanins.

  17. Kefir drink leads to a similar weight loss, compared with milk, in a dairy-rich non-energy-restricted diet in overweight or obese premenopausal women: a randomized controlled trial.

    Science.gov (United States)

    Fathi, Yasamin; Faghih, Shiva; Zibaeenezhad, Mohammad Javad; Tabatabaei, Sayed Hamid Reza

    2016-02-01

    Controversy exists regarding whether increasing dairy intake without energy restriction would lead to weight loss. We aimed to compare the potential weight-reducing effects of kefir drink (a probiotic dairy product) and milk in a dairy-rich non-energy-restricted diet in overweight or obese premenopausal women. One hundred and forty-four subjects were assessed for eligibility in this single-center, multi-arm, parallel-group, randomized controlled trial. Of these, seventy-five eligible women aged 25-45 years were randomly assigned to three groups, labeled as control, milk, and kefir, to receive an outpatient dietary regimen for 8 weeks. Subjects in the control group received a diet providing a maintenance level of energy intake, containing 2 servings/day of low-fat dairy products, while those in the milk and kefir groups received a weight maintenance diet, containing 2 additional servings/day (a total of 4 servings/day) of dairy products from low-fat milk or commercial kefir drink, respectively. Anthropometric outcomes including weight, body mass index (BMI), and waist circumference (WC) were measured every 2 weeks. Fifty-eight subjects completed the study. Using analysis of covariance models in the intention-to-treat population (n = 75), we found that at 8 weeks, subjects in the kefir and milk groups had significantly greater reductions in weight, BMI, and WC compared to those in the control group (all p kefir and milk groups. Kefir drink leads to a similar weight loss, compared with milk, in a dairy-rich non-energy-restricted diet in overweight or obese premenopausal women. However, further studies are warranted.

  18. Near Real Time Change-Point detection in Optical and Thermal Infrared Time Series Using Bayesian Inference over the Dry Chaco Forest

    Science.gov (United States)

    Barraza Bernadas, V.; Grings, F.; Roitberg, E.; Perna, P.; Karszenbaum, H.

    2017-12-01

    The Dry Chaco region (DCF) has the highest absolute deforestation rates of all Argentinian forests. The most recent report indicates a current deforestation rate of 200,000 Ha year-1. In order to better monitor this process, DCF was chosen to implement an early warning program for illegal deforestation. Although the area is intensively studied using medium resolution imagery (Landsat), the products obtained have a yearly pace and therefore unsuited for an early warning program. In this paper, we evaluated the performance of an online Bayesian change-point detection algorithm for MODIS Enhanced Vegetation Index (EVI) and Land Surface Temperature (LST) datasets. The goal was to to monitor the abrupt changes in vegetation dynamics associated with deforestation events. We tested this model by simulating 16-day EVI and 8-day LST time series with varying amounts of seasonality, noise, length of the time series and by adding abrupt changes with different magnitudes. This model was then tested on real satellite time series available through the Google Earth Engine, over a pilot area in DCF, where deforestation was common in the 2004-2016 period. A comparison with yearly benchmark products based on Landsat images is also presented (REDAF dataset). The results shows the advantages of using an automatic model to detect a changepoint in the time series than using only visual inspection techniques. Simulating time series with varying amounts of seasonality and noise, and by adding abrupt changes at different times and magnitudes, revealed that this model is robust against noise, and is not influenced by changes in amplitude of the seasonal component. Furthermore, the results compared favorably with REDAF dataset (near 65% of agreement). These results show the potential to combine LST and EVI to identify deforestation events. This work is being developed within the frame of the national Forest Law for the protection and sustainable development of Native Forest in Argentina in

  19. Thermal Effects on the Body mass, Transpiration rate, Feeding and Food Conversion of the Pillbug Armadillo officinalis (Isopoda, Oniscidea Fed on the Dry Leaf of Punica Granatum

    Directory of Open Access Journals (Sweden)

    Abdelgader K. Youssef

    2004-06-01

    Full Text Available Observations were made on the body mass; transpiration rate; assimilation efficiency; gross and net production efficiencies; feeding, assimilation, conversion and metabolic rates of the pillbug Armadillo officinalis Dumeril acclimatized at 14º  and 21 °C for 15 days and fed on the dry leaf of Punica granatum (Pomegranate.  A brief description is given on the chemical composition of P. granatum leaf.  The difference in body mass increments of A. officinalis between the acclimatized temperatures was not significant (t = 1.09; p>0.05.  However, significant differences were discernible on the transpiration rate (t = 9.53; p<0.01, moisture (t = 9.01; p<0.01, assimilation efficiency (t = 5.16; p<0.01, feeding (t = 3.76; p<0.05 and conversion (t = 2.58; p<0.05  rates between the woodlice acclimatized at 14º and 21 °C.  Better feeding of    P. granatum leaf by these animals was observed at 21° C, but better assimilation efficiency at 14 °C.  Only 3.21% assimilated food at 14° C and 6.30% at 21 °C were converted into the production of new tissues.  The food consumption of A. officinalis at 14º and 21° C was 2.05% and 3.79% body mass/day respectively.  The effect of temperature on the activity of A. officinalis in the field is discussed.

  20. Evaluation of a functional soy product with addition of soy fiber and fermented with probiotic kefir culture

    Directory of Open Access Journals (Sweden)

    Tahis Regina Baú

    2014-06-01

    Full Text Available The objective of this study was to evaluate the chemical, sensory properties and stability of a functional soy product with soy fiber and fermented with probiotic kefir culture. The product was characterized by the chemical composition, color and sensory analysis. The stability of the product was evaluated by pH, acidity, viscosity, firmness, syneresis measurements and cells counts. The functional soy product presented better chemical composition and difference in color compared to the fermented product without fiber. Sensory analysis showed that the functional soy product had good acceptance and had better firmness and reduced syneresis compared to fermented product without fiber. The lactic acid bacteria counts decreased slightly during 28 days at 4°C of the storage and the product showed good microbiological stability. The functional soy product due to high Lactococcus lactis counts could be considered as a probiotic for the entire storage period.

  1. Kefir and champagne vinegar to defeat bacterial vaginosis in woman, avoiding oral metronidazole, clindamycin and bothersome douchings

    Directory of Open Access Journals (Sweden)

    Piotr Brzezinski

    2018-02-01

    Full Text Available Scope ouf our study is to treat with natural remedies vaginitis in woman, when it has been detected the disease originates from bacterical assault (Gardnerella vaginalis and/or Streptococca spp. in order to avoid the administration of perilous antibiotics and elicit sexual desire and eliminate pain during urination in the woman who has suffered from this disease after 4-5 days only. We have to proceed with the preliminary phase of a simplest test (the ammin whiff test and determine the type of vaginitis and thus treat it using champagne or cider vinegar to adjust mucosal pH and kefir, a fermented beverage, that is extremely rich in mesophyllic bacteria, apt to reveal an important and suggestive function regard vaginal microbes.

  2. High-intensity drying processes: Impulse drying. Annual report

    Energy Technology Data Exchange (ETDEWEB)

    Orloff, D.I.; Phelan, P.M.

    1993-12-01

    Experiments were conducted on a sheet-fed pilot-scale shoe press to compare impulse drying and double-felted pressing. Both an IPST (Institute of Paper Science and Technology) ceramic coated and Beloit Type A press roll were evaluated for lienrboard sheet structures having a wide range of z-direction permeability. Purpose was to find ways of correcting sheet sticking problems observed in previous pilot-scale shoe press experiments. Results showed that impulse drying was superior to double felted pressing in both press dryness and in important paper physical properties. Impulse drying critical temperature was found to depend on specific surface of the heated layer of the sheet, thermal properties of the press roll surface, and choice of felt. Impulse drying of recycled and two-ply liner was demonstrated for both Southern Pile and Douglas fir-containing furnishes.

  3. A Radiochemical Biotechnological Approach: Preliminary Study of Lactose Uptake Rate by Kefir Cells, Using 14C-labeled Lactose, in Anaerobic Fermentation

    International Nuclear Information System (INIS)

    Golfinopoulos, A.; Soupioni, M.; Kanellaki, M.; Koutinas, A. A.

    2008-01-01

    The effect of initial lactose concentration on lactose uptake rate by kefir free cells, during the lactose fermentation, was studied in this work. For the investigation 14 C-labelled lactose was used due to the fact that labeled and unlabeled molecules are fermented in the same way. The results illustrated lactose uptake rates are about up to two fold higher at lower initial (convolution sign)Be densities as compared with higher initial (convolution sign)Be densities

  4. A Radiochemical Biotechnological Approach: Preliminary Study of Lactose Uptake Rate by Kefir Cells, Using 14C-labeled Lactose, in Anaerobic Fermentation

    Science.gov (United States)

    Golfinopoulos, A.; Soupioni, M.; Kanellaki, M.; Koutinas, A. A.

    2008-08-01

    The effect of initial lactose concentration on lactose uptake rate by kefir free cells, during the lactose fermentation, was studied in this work. For the investigation 14C-labelled lactose was used due to the fact that labeled and unlabeled molecules are fermented in the same way. The results illustrated lactose uptake rates are about up to two fold higher at lower initial ∘Bé densities as compared with higher initial ∘Bé densities.

  5. Evaluation of the isoflavone and total phenolic contents of kefir-fermented soymilk storage and after the in vitro digestive system simulation.

    Science.gov (United States)

    da Silva Fernandes, Meg; Sanches Lima, Fernando; Rodrigues, Daniele; Handa, Cintia; Guelfi, Marcela; Garcia, Sandra; Ida, Elza Iouko

    2017-08-15

    This study aimed to evaluate the isoflavone and total phenolic contents in kefir-fermented soymilk storage and after the in vitro digestive system simulation (DSS). Soymilk was fermented with kefir culture (0.02UC/L) at 25°C for 15h and stored at 4°C for 4days. After the fermentation and storage, the isoflavone and total phenolic contents were quantified by high performance liquid chromatography and spectrophotometry, respectively. The cell viability of lactic acid bacteria and yeast was evaluated. Fermentation promoted an increase of approximately 3log CFU/g cycles of the microorganisms and the storage process did not alter the aglycone isoflavones and total phenolic contents. The content of aglycone isoflavones increased 2-fold, and the total phenolic content increased 9-fold. Therefore, kefir-fermented soymilk is a good source of aglycone isoflavones and phenolics, since the content of these substances was increased significantly after the in vitro digestive system simulation of the product. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Español Eye Health / Eye Health A-Z Dry Eye Sections What Is Dry Eye? Dry Eye Symptoms ... Dry Eye Dry Eye Treatment What Is Dry Eye? Leer en Español: ¿Qué es el ojo seco? ...

  7. Acid-base properties of humic substances from composted and thermally-dried sewage sludges and amended soils as determined by potentiometric titration and the NICA-Donnan model.

    Science.gov (United States)

    Fernández, José M; Plaza, César; Senesi, Nicola; Polo, Alfredo

    2007-09-01

    The acid-base properties of humic acids (HAs) and fulvic acids (FAs) isolated from composted sewage sludge (CS), thermally-dried sewage sludge (TS), soils amended with either CS or TS at a rate of 80 t ha(-1)y(-1) for 3y and the corresponding unamended soil were investigated by use of potentiometric titrations. The non-ideal competitive adsorption (NICA)-Donnan model for a bimodal distribution of proton binding sites was fitted to titration data by use of a least-squares minimization method. The main fitting parameters of the NICA-Donnan model obtained for each HA and FA sample included site densities, median affinity constants and widths of affinity distributions for proton binding to low and high affinity sites, which were assumed to be, respectively, carboxylic- and phenolic-type groups. With respect to unamended soil HA and FA, the HAs and FAs from CS, and especially TS, were characterized by smaller acidic functional group contents, larger proton binding affinities of both carboxylic- and phenolic-type groups, and smaller heterogeneity of carboxylic and phenolic-type groups. Amendment with CS or TS led to a decrease of acidic functional group contents and a slight increase of proton binding affinities of carboxylic- and phenolic-type groups of soil HAs and FAs. These effects were more evident in the HA and FA fractions from CS-amended soil than in those from TS-amended soil.

  8. Recent advances in fluidized bed drying

    Science.gov (United States)

    Haron, N. S.; Zakaria, J. H.; Mohideen Batcha, M. F.

    2017-09-01

    Fluidized bed drying are very well known to yield high heat and mass transfer and hence adopted to many industrial drying processes particularly agricultural products. In this paper, recent advances in fluidized bed drying were reviewed and focus is given to the drying related to the usage of Computational Fluid Dynamics (CFD). It can be seen that usage of modern computational tools such as CFD helps to optimize the fluidized bed dryer design and operation for lower energy consumption and thus better thermal efficiency. Among agricultural products that were reviewed in this paper were oil palm frond, wheat grains, olive pomace, coconut, pepper corn and millet.

  9. Heat jettisoning from solar-thermal driven LiBr-H{sub 2}O absorber cooling units by pulsed spraying a dry cooler with water; Waermeabwurf aus einer solarthermisch getriebenen LiBr- H{sub 2}O Absorptionskaeltemaschine durch gepulstes Bespruehen eines Trockenkuehlers mit Wasser

    Energy Technology Data Exchange (ETDEWEB)

    Gantenbein, P.; Helfenberger, R.; Frank, E.

    2010-07-01

    This short, illustrated final report discusses the removal of heat from solar-thermal driven LiBr-H{sub 2}O absorber cooling units by pulsed spraying a dry cooler with water. The reduction of electricity consumption for room cooling using conventional chillers is examined. Heat dissipation using open cooling towers and the disadvantages encountered are compared with heat dissipation using a dry cooler with heat-exchanger and fans. Additional evaporation cooling achieved by spraying the heat exchanger with water is described and discussed. The results of measurements made at the Institute for Solar Technology in Rapperswil, Switzerland, are presented and discussed.

  10. Kefir alleviates obesity and hepatic steatosis in high-fat diet-fed mice by modulation of gut microbiota and mycobiota: targeted and untargeted community analysis with correlation of biomarkers.

    Science.gov (United States)

    Kim, Dong-Hyeon; Kim, Hyunsook; Jeong, Dana; Kang, Il-Byeong; Chon, Jung-Whan; Kim, Hong-Seok; Song, Kwang-Young; Seo, Kun-Ho

    2017-06-01

    Kefir is a probiotic beverage containing over 50 species of lactic acid bacteria and yeast. In this study, the anti-obesity and anti-non-alcoholic fatty liver disease (NAFLD) effects of kefir were comprehensively addressed along with targeted and untargeted community analysis of the fecal microbiota in a high-fat diet (HFD)-induced obese mouse model. HFD-fed C57BL/6 mice were orally administrated either kefir or milk (control) once a day for 12 weeks, and body and organ weight, fecal microbiota and mycobiota, histopathology, blood cholesterol and cytokines and gene expressions were analyzed. Compared to the control, mice in the kefir group exhibited a significantly lower body weight (34.18 g vs. 40.24 g; p=0.00004) and histopathological liver lesion score (1.13 vs. 3.25; p=0.002). Remarkably, the kefir-fed mice also harbored more Lactobacillus/Lactococcus (7.01 vs. 6.32 log CFU/g), total yeast (6.07 vs. 5.01 log CFU/g) and Candida (5.56 vs. 3.88 log CFU/g). Kefir administration also up-regulated genes related to fatty acid oxidation, PPARα and AOX, in both the liver and adipose tissue (PPARα, 2.95- and 2.15-fold; AOX, 1.89- and 1.9-fold, respectively). The plasma concentration of IL-6, a proinflammatory marker, was significantly reduced following kefir consumption (50.39 pg/ml vs. 111.78 pg/ml; p=0.03). Strikingly, the populations of Lactobacillus/Lactococcus, total yeast and Candida were strongly correlated with PPARα gene expression in adipose and hepatic tissue (r=0.599, 0.580 and 0.562, respectively). These data suggest that kefir consumption modulates gut microbiota and mycobiota in HFD-fed mice, which prevents obesity and NAFLD via promoting fatty acid oxidation. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. High-intensity drying processes-impulse drying

    Energy Technology Data Exchange (ETDEWEB)

    Orloff, D.I.

    1991-06-01

    Impulse drying is an innovative process for drying paper that holds great promise for reducing the energy consumed during the manufacture of paper and similar web products. impulse drying occurs when a wet paper web passes through a press nip in which one of the rolls is heated to a high temperature. A steam layer adjacent to the heated surface grows and displaces water from the sheet in a very efficient manner. The energy required for water removal is very much less than that required for conventional evaporative drying. To eliminate sheet delamination, low thermal mass ceramic press roll coatings were developed to reduce heat transfer to the sheet, while maintaining high heat flux during early stages of the process. In so doing, most of the transferred energy is used to form steam that displaces liquid water, rather than in excessively heating the sheet. During this period, a prototype ceramic coating was developed and its impulse drying performance was compared to that of steel surfaces. It was observed that ceramic platens can be operated at higher temperatures and pressures resulting in improved water removal and physical properties without inducing sheet delamination. Heat flux measurement techniques were developed to provide a mechanistic explanation for the superior performance of the prototype. The work confirmed that the prototype ceramic coating is more energy efficient than the steel surface.

  12. High-intensity drying processes-impulse drying. Yearly report

    Energy Technology Data Exchange (ETDEWEB)

    Orloff, D.I.

    1991-06-01

    Impulse drying is an innovative process for drying paper that holds great promise for reducing the energy consumed during the manufacture of paper and similar web products. impulse drying occurs when a wet paper web passes through a press nip in which one of the rolls is heated to a high temperature. A steam layer adjacent to the heated surface grows and displaces water from the sheet in a very efficient manner. The energy required for water removal is very much less than that required for conventional evaporative drying. To eliminate sheet delamination, low thermal mass ceramic press roll coatings were developed to reduce heat transfer to the sheet, while maintaining high heat flux during early stages of the process. In so doing, most of the transferred energy is used to form steam that displaces liquid water, rather than in excessively heating the sheet. During this period, a prototype ceramic coating was developed and its impulse drying performance was compared to that of steel surfaces. It was observed that ceramic platens can be operated at higher temperatures and pressures resulting in improved water removal and physical properties without inducing sheet delamination. Heat flux measurement techniques were developed to provide a mechanistic explanation for the superior performance of the prototype. The work confirmed that the prototype ceramic coating is more energy efficient than the steel surface.

  13. In vitro and in vivo evaluation of the probiotic attributes of Lactobacillus kefiranofaciens XL10 isolated from Tibetan kefir grain.

    Science.gov (United States)

    Xing, Zhuqing; Tang, Wei; Geng, Weitao; Zheng, Yongna; Wang, Yanping

    2017-03-01

    Lactobacillus kefiranofaciens XL10, with a high yield of extracellular polysaccharide (EPS), is isolated from Tibetan kefir grain and benefits the health of human beings and has been considered to exhibit probiotic potential in vitro and in vivo. The probiotic function of the strain was studied extensively, viz., acid and bile salt tolerances, cell surface hydrophobicity and autoaggregation, the modulation of gut microbiota, and the distribution and colonization of XL10 in the mouse intestinal tract after oral administration. XL10 could survive 3-h incubation at pH 3.5 and exhibited cell surface hydrophobicity of ∼79.9% and autoaggregation of ∼27.8%. After continuous oral administration of XL10 for 2 weeks, the Bifidobacteriaceae family increased, accompanied by an observable decline in Proteobacteria phyla in the tested mice. Butyrivibrio and Pseudobutyrivibrio, recognized as butyric acid-producing bacteria, could also be detected at day 7 and day 14, respectively. The most abundant community in the mouse gut had formed by day 14. Additionally, we found that XL10 successfully adhered to the mucous tissue and colonized the ileum of the mice based on fluorescence imaging, flow cytometry, and qPCR. Our results suggested that XL10 has excellent probiotic properties and represents an alternative for exploitation in the development of novel functional foods.

  14. Kefir-isolated bacteria and yeasts inhibit Shigella flexneri invasion and modulate pro-inflammatory response on intestinal epithelial cells.

    Science.gov (United States)

    Bolla, P A; Abraham, A G; Pérez, P F; de Los Angeles Serradell, M

    2016-02-01

    The aim of this work was to evaluate the ability of a kefir-isolated microbial mixture containing three bacterial and two yeast strains (MM) to protect intestinal epithelial cells against Shigella flexneri invasion, as well as to analyse the effect on pro-inflammatory response elicited by this pathogen. A significant decrease in S. flexneri strain 72 invasion was observed on both HT-29 and Caco-2 cells pre-incubated with MM. Pre-incubation with the individual strains Saccharomyces cerevisiae CIDCA 8112 or Lactococcus lactis subsp. lactis CIDCA 8221 also reduced the internalisation of S. flexneri into HT-29 cells although in a lesser extent than MM. Interestingly, Lactobacillus plantarum CIDCA 83114 exerted a protective effect on the invasion of Caco-2 and HT-29 cells by S. flexneri. Regarding the pro-inflammatory response on HT-29 cells, S. flexneri infection induced a significant activation of the expression of interleukin 8 (IL-8), chemokine (C-C motif) ligand 20 (CCL20) and tumour necrosis factor alpha (TNF-α) encoding genes (Pkefir, resulted in inhibition of S. flexneri internalisation into human intestinal epithelial cells, along with the inhibition of the signalling via NF-κB that in turn led to the attenuation of the inflammatory response.

  15. Effect of milk fermentation by kefir grains and selected single strains of lactic acid bacteria on the survival of Mycobacterium bovis BCG.

    Science.gov (United States)

    Macuamule, C L S; Wiid, I J; van Helden, P D; Tanner, M; Witthuhn, R C

    2016-01-18

    Mycobacterium bovis that causes Bovine tuberculosis (BTB) can be transmitted to humans thought consumption of raw and raw fermented milk products from diseased animals. Lactic acid bacteria (LAB) used in popular traditional milk products in Africa produce anti-microbial compounds that inhibit some pathogenic and spoilage bacteria. M. bovis BCG is an attenuated non-pathogenic vaccine strain of M. bovis and the aim of the study was to determine the effect of the fermentation process on the survival of M. bovis BCG in milk. M. bovis BCG at concentrations of 6 log CFU/ml was added to products of kefir fermentation. The survival of M. bovis BCG was monitored at 12-h intervals for 72 h by enumerating viable cells on Middlebrook 7H10 agar plates enriched with 2% BD BACTEC PANTA™. M. bovis BCG was increasingly reduced in sterile kefir that was fermented for a period of 24h and longer. In the milk fermented with kefir grains, Lactobacillus paracasei subsp. paracasei or Lactobacillus casei, the viability of M. bovis BCG was reduced by 0.4 logs after 24h and by 2 logs after 48 h of fermentation. No viable M. bovis BCG was detected after 60 h of fermentation. Results from this study show that long term fermentation under certain conditions may have the potential to inactivate M. bovis BCG present in the milk. However, to ensure safety of fermented milk in Africa, fermentation should be combined with other hurdle technologies such as boiling and milk pasteurisation. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Chemical, Physiochemical, and Microstructural Properties, and Probiotic Survivability of Fermented Goat Milk Using Polymerized Whey Protein and Starter Culture Kefir Mild 01.

    Science.gov (United States)

    Wang, Hao; Wang, Cuina; Wang, Mu; Guo, Mingruo

    2017-11-01

    A set-type fermented goat milk (FGM) using polymerized whey protein (PWP) as main thickening agent and Kefir Mild 01 as starter culture was developed. The FGM with PWP (0.3%, w/v) and pectin (0.2%, w/v) had low syneresis (5.44 ± 0.92%), desirable viscosity (952.86 ± 61.52 mPa⋅s), and hardness (112.57 ± 3.23 g), which were comparable to a fermented cow milk. Sensory evaluation data showed that the FGM with PWP and pectin had higher scores of both flavor (4.41 ± 0.39) and taste (3.72 ± 0.34) than the sample without PWP. Chemical composition of both fermented goat and cow milk were analyzed. The protein content of goat and cow milk samples were 3.50% ± 0.12% and 3.28% ± 0.09% (w/w), respectively. Lactobacillus acidophilus population in both FGM samples remained above 10 6 CFU/g during the 1st 4-wk storage. There was a slight but no significant (P > 0.05) decrease in pH and TA during storage. Scanning electron microscopy micrographs displayed a compact and homogeneous protein network of the FGM with PWP and pectin. Polymerized whey protein may be a novel protein-based thickening agent for formulation of a set-type FGM with starter culture Kefir Mild 01. Fermented goat milk is an increasingly popular dairy product in the world. However, it is difficult to make set type fermented goat milk due to the smaller size and lower content of casein micelles in goat milk. A fermented goat milk with PWP (0.3%, w/v) and pectin (0.2%, w/v) was successfully developed in this study. The product fermented by Kefir Mild 01 starter culture had a similar taste with Kefir but no yeast or alcoholic exists. The new product would be a promising food in the market. © 2017 Institute of Food Technologists®.

  17. Immunohistochemical examination of effects of kefir, koumiss and commercial probiotic capsules on platelet derived growth factor-c and platelet derived growth factor receptor-alpha expression in mouse liver and kidney.

    Science.gov (United States)

    Bakir, B; Sari, E K; Aydin, B D; Yildiz, S E

    2015-04-01

    We investigated using immunohistochemistry the effects of kefir, koumiss and commercial probiotic capsules on the expression of platelet derived growth factor-c (PDGF-C) and platelet derived growth factor receptor-alpha (PDGFR-α) in mouse liver and kidney. Mice were assigned to four groups: group 1 was given commercial probiotic capsules, group 2 was given kefir, group 3 was given koumiss and group 4 was untreated. After oral administration for 15 days, body weights were recorded and liver and kidney tissue samples were obtained. Hematoxylin and eosin staining was used to examine histology. PDGF-C and PDGFR-α in liver and kidney were localized using the streptavidin-biotin peroxidase complex method (ABC). We found that the weights of the mice in the kefir, koumiss and commercial probiotic capsules groups increased compared to the control group. No differences in liver and kidney histology were observed in any of the experimental groups. Kefir, koumiss and the commercial probiotic preparation increased PDGF-C and PDGFR-α expression.

  18. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Eye Symptoms Causes of Dry Eye Dry Eye Treatment What Is Dry Eye? Leer en Español: ¿Qué ... Your Eyelid Nov 29, 2017 New Dry Eye Treatment is a Tear-Jerker Jul 21, 2017 Three ...

  19. Effects of Clear Kefir on Biomolecular Aspects of Glycemic Status of Type 2 Diabetes Mellitus (T2DM Patients in Bandung, West Java [Study on Human Blood Glucose, c Peptide and Insulin

    Directory of Open Access Journals (Sweden)

    Judiono J

    2014-08-01

    Full Text Available Background: Diabetes Mellitus (DM triggers an excessive reaction of free-radicals. It increases reactive oxygen species and reduces antioxidants status as well as the β cell damage. Clear kefir was used for DM therapies, however it limited biomolecular exploration of its bioactive roles. Research aimed to investigate the effects of clear kefir on the biomolecular nature of the glycemic status of T2DM in Bandung. Methods: The randomized pretest-posttest control group was conducted by 106 T2DM patients. Research was done in several hospitals in Bandung and Cimahi, West Java from 2012–2013. Samples were divided randomly into three groups: (1 T2DM with HbA1c 7 fed standard diet and supplemented 200 ml/day by clear kefir, (3 T2DM with HbA1c was fed a standard diet as a control group. Dose response was obtained from a preeliminary vivo study, and then converted to human dosage by year 2011. Intervention was effectively done for 30 days. HbA1c was measured by HPLC. Fasting blood glucose (FBG and Postprandial blood glucose levels (PBG were measured by enzymes levels. C Peptide and insulin were measured by Elisa. Data was analyzed by a statictics programme by significance p<0,05. Study was approved by ethic committee. Results : HbA1c was significantly reduced in delta level (p<0.01 and FBG (p<0.015 among kefir groups. PBG was not significantly reduced among groups. C-Peptide was significantly increased in delta level, except in control group (p<0.014. Insulin was reduced significantly, except in control group (p<0.003. Conclusions : Supplementation of clear kefir reduced blood glucose levels (HbA1c, FBG, PBG and increased c-peptide. Clear kefir’s biomolecular mechanisms and chemistry characterization is a challenge for future studies.

  20. Solar Trap for Banana Drying Method

    Directory of Open Access Journals (Sweden)

    Musa S.

    2017-01-01

    Full Text Available Food drying methods nowadays are mostly in high use of electricity and fuel which lead to high operational cost. This has resulted in a waste of energy and money due to the use of modern tools requires significant costs for implementation. Meanwhile, the traditional food drying process only uses sun rays in their process, where the process is far more efficient than the modern drying method. In this study, the test was conducted to determine the trapped solar heat energy requirements for the process of drying foods such as agricultural products, particularly bananas. The solar trap test by using solar trap container was carried out include determining the thermal energy requirement for drying, preparing equipment (solar trap container to trap solar energy, handling and drying tests on samples of bananas. The percentage amount of water removal and energy required for the drying process was found to be 48% and 134 J. The results of this study can determine that solar trap drying method is easier, quicker and more effective than the usual method of drying because it use natural solar energy. Several proposals have been suggested for improvement for future study, such as controlling the solar trap air in the container, replacing the trap solar wall with a darker color, examining the floors slope so that more solar traps collected and installing a small hose on the base of the container so that the water evaporated in the solar trap may exit through the route.

  1. Co-production of functional exopolysaccharides and lactic acid by Lactobacillus kefiranofaciens originated from fermented milk, kefir.

    Science.gov (United States)

    Cheirsilp, Benjamas; Suksawang, Suwannee; Yeesang, Jarucha; Boonsawang, Piyarat

    2018-01-01

    Kefiran is a functional exopolysaccharide produced by Lactobacillus kefiranofaciens originated from kefir, traditional fermented milk in the Caucasian Mountains, Russia. Kefiran is attractive as thickeners, stabilizers, emulsifiers, gelling agents and also has antimicrobial and antitumor activity. However, the production costs of kefiran are still high mainly due to high cost of carbon and nitrogen sources. This study aimed to produce kefiran and its co-product, lactic acid, from low-cost industrial byproducts. Among the sources tested, whey lactose (at 2% sugar concentration) and spent yeast cells hydrolysate (at 6 g-nitrogen/L) gave the highest kefiran of 480 ± 21 mg/L along with lactic acid of 20.1 ± 0.2 g/L. The combination of these two sources and initial pH were optimized through Response Surface Methodology. With the optimized medium, L. kefiranofaciens produced more kefiran and lactic acid up to 635 ± 7 mg/L and 32.9 ± 0.7 g/L, respectively. When the pH was controlled to alleviate the inhibition from acidic pH, L. kefiranofaciens could consume all sugars and produced kefiran and lactic acid up to 1693 ± 29 mg/L and 87.49 ± 0.23 g/L, respectively. Moreover, the fed-batch fermentation with intermittent adding of whey lactose improved kefiran and lactic acid productions up to 2514 ± 93 mg/L and 135 ± 1.75 g/L, respectively. These results indicate the promising approach to economically produce kefiran and lactic acid from low-cost nutrient sources.

  2. PULSE DRYING EXPERIMENT AND BURNER CONSTRUCTION

    Energy Technology Data Exchange (ETDEWEB)

    Robert States

    2006-07-15

    Non steady impingement heat transfer is measured. Impingement heating consumes 130 T-BTU/Yr in paper drying, but is only 25% thermally efficient. Pulse impingement is experimentally shown to enhance heat transfer by 2.8, and may deliver thermal efficiencies near 85%. Experimental results uncovered heat transfer deviations from steady theory and from previous investigators, indicating the need for further study and a better theoretical framework. The pulse burner is described, and its roll in pulse impingement is analyzed.

  3. Drying textile yarns

    Energy Technology Data Exchange (ETDEWEB)

    McCullough, H.C.

    1987-05-20

    The material drying apparatus described comprises a moisture withdrawal or drying section, wherein a tray carrying textile yarn bobbins is removably installed, a heat input section and recirculating ducting for recirculating a flow of drying gas between the heat input and withdrawal sections such that moisture taken from the material in the moisture withdrawal section is removed from the drying gas in the heat input section. A receptable means is provided for the collection of condensate. Preferably the heat input section includes a heat pump: thus the drying gas passing from the drying section laden with moisture can be directed through a condensing section of the heat pump for dehumidification.

  4. Technological functional properties of soy, oat and wheat fibers and soy products with added fibers and fermented with kefir culturePropriedades funcionais tecnológicas das fibras de soja, aveia e trigo e produtos de soja com adição de fibras e fermentados com cultura de kefir

    Directory of Open Access Journals (Sweden)

    Elza Iouko Ida

    2012-02-01

    Full Text Available The objective of this study was to characterize the technological functional properties of soy, oats and wheat fibers and evaluate soy products with added fiber and fermented with kefir. The fibers were characterized with regard to pH, water adsorption capacity, water and oil absorption capacity and swelling volume. Soy products were developed with the addition of 3% soy fiber, oat and wheat and fermented with kefir. The fermented products were characterized for pH, acidity, syneresis, viscosity and firmness, Lactococcus lactis counts and analysis of sanitary conditions. The soy fiber showed a higher content of protein and lipids, pH, water adsorption and adsorption capacity. The wheat fiber showed a higher oil absorption capacity. The addition of soy, oat and wheat fibers influence pH, acidity, syneresis, viscosity and firmness of fermented soy products with kefir. The lowest syneresis and highest viscosity and firmness were obtained with the soy fermented products with soy fiber. The addition of soy fiber stimulated Lactococcus lactis growth. The fermented soy products had enough Lactococcus lactis counts to be considered probiotics. The products presented satisfactory hygienic sanitary conditions.O objetivo deste trabalho foi caracterizar as propriedades funcionais tecnológicas das fibras de soja, aveia e trigo e avaliar os produtos de soja com adição de fibras e fermentados com cultura de kefir. As fibras foram caracterizadas quanto a composição química, pH, capacidade de adsorção e absorção de água, capacidade de absorção de óleo e volume de intumescimento. Foram desenvolvidos produtos de soja com adição de 3% de fibra de soja, aveia e trigo e fermentados com cultura de kefir. Os produtos fermentados foram caracterizados quanto o pH, acidez, sinerese, viscosidade e firmeza, contagem de Lactococcus lactis e análise das condições higiênico-sanitárias. A fibra de soja apresentou maior teor de proteínas e lipídios, p

  5. Dry Mouth (Xerostomia)

    Science.gov (United States)

    ... Finding Dental Care Home Health Info Health Topics Dry Mouth Saliva, or spit, is made by the salivary ... help keep teeth strong and fight tooth decay. Dry mouth, also called xerostomia (ZEER-oh-STOH-mee-ah), ...

  6. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Symptoms Causes of Dry Eye Dry Eye Treatment What Is Dry Eye? Leer en Español: ¿Qué es ... the tear film. It makes up most of what we see as tears. This layer cleans the ...

  7. Elaboração e caracterização físico-química de antepastos funcionais utilizando kefir e semente de chia / Elaboration and physical-chemical characterization of functional antipasto using kefir and chia seed

    OpenAIRE

    Campolina, Gabriela Aguiar; Faria, Marco Aurélio da Silva; Carvalho, Naiara Barbosa; Villanoeva, Camila Nair Batista

    2017-01-01

    Os alimentos funcionais têm sido cada vez mais conhecidos e consequentemente mais consumidos pela população, devido à preocupação cada vez maior com a saúde e o bem-estar. Dentre os alimentos funcionais, merecem destaque os lácteos funcionais por serem os mais conhecidos pelos consumidores. O kefir, apesar de ser pouco consumido no Brasil é um alimento que proporciona aos consumidores alguns benefícios que merecem ser estudados e disseminados. Partindo dessas características, o presente traba...

  8. Effect of starter culture and inulin addition on microbial viability, texture, and chemical characteristics of whole or skim milk Kefir Efeito do tipo de cultura starter e da adição de inulina na viabilidade microbiana, textura e características químicas de Kefir de leite integral ou desnatado

    Directory of Open Access Journals (Sweden)

    Flávia Daiana Montanuci

    2012-12-01

    Full Text Available The effect of inulin addition and starters (Kefir grains or commercial starter culture on the microbial viability, texture, and chemical characteristics of Kefir beverages prepared with whole or skim milk was evaluated during refrigerated storage. The type of starter did not influence microbial viability during the storage of the beverages, but the chemical and textural changes (decreases in pH, lactose concentration, and inulin and increased acidity, firmness, and syneresis were more pronounced in the formulations fermented with grains than those fermented with the starter culture. The addition of inulin did not influence acidity or viability of lactic acid bacteria, but in general, its effect on the survival of acetic acid bacteria, Lactococcus and yeasts, firmness, and syneresis depended on the type of milk and starter culture used. Generally, the yeast, acetic acid bacteria, and Leuconostoc counts increased or remained unchanged, while the total population of lactic acid bacteria and Lactococcus were either reduced by 1 to 2 logs or remained unchanged during storage.O efeito da adição de inulina e do tipo de iniciador (grãos de Kefir ou cultura starter comercial da fermentação sobre a viabilidade microbiana, textura e características químicas de bebidas Kefir, formuladas com leite integral ou desnatado, foi avaliado durante o armazenamento refrigerado. O tipo de iniciador não teve influência sobre a viabilidade microbiana ao longo da estocagem das bebidas, mas as alterações químicas e de textura (redução do pH, teores de lactose e inulina e aumento da acidez, firmeza e sinérese foram mais acentuadas nas formulações fermentadas com grãos do que com cultura starter. A adição de inulina não influenciou a acidez ou a viabilidade de bactérias ácido-láticas, mas, em geral, seu efeito sobre a sobrevivência das bactérias ácido-acéticas, Lactococcus e leveduras, firmeza e sinérese foi dependente do tipo de leite e da

  9. Dry and Semi-Dry Tropical Cyclones

    Science.gov (United States)

    Cronin, T.; Chavas, D. R.

    2017-12-01

    Our understanding of dynamics in our real moist atmosphere is strongly informed by idealized dry models. It is widely believed that tropical cyclones (TCs) are an intrinsically moist phenomenon - relying fundamentally on evaporation and latent heat release - yet recent numerical modeling work has found formation of dry axisymmetric tropical cyclones from a state of dry radiative-convective equilibrium. What can such "dry hurricanes" teach us about intensity, structure, and size of real moist tropical cyclones in nature? Are dry TCs even stable in 3D? What about surfaces that are nearly dry but have some latent heat flux - can they also support TCs? To address these questions, we use the SAM cloud-system resolving model to simulate radiative-convective equilibrium on a rapidly rotating f-plane, subject to constant tropospheric radiative cooling. We use a homogeneous surface with fixed temperature and with surface saturation vapor pressure scaled by a factor 0-1 relative to that over pure water - allowing for continuous variation between moist and dry limits. We also explore cases with surface enthalpy fluxes that are uniform in space and time, where partitioning between latent and sensible heat fluxes is specified directly. We find that a completely moist surface yields a TC-world where multiple vortices form spontaneously and persist for tens of days. A completely dry surface can also yield a parallel dry TC-world with many vortices that are even more stable and persistent. Spontaneous cyclogenesis, however, is impeded for a range of low to intermediate surface wetness values, and by the combination of large rotation rates and a dry surface. We discuss whether these constraints on spontaneous cyclogenesis might arise from: 1) rain evaporation in the subcloud layer limiting the range of viable surface wetness values, and 2) a natural convective Rossby number limiting the range of viable rotation rates. Finally, we discuss simulations with uniform surface enthalpy

  10. Vendor Testing of Sensitive Compounds in Simulated Dry Sludge

    International Nuclear Information System (INIS)

    Dworjanyn, L.O.

    1999-01-01

    This assessment covers thermal screening, differential scanning calorimetry, and impact sensitivity testing on Mercury Fulminate, and mixtures of the fulminate in dry inorganic sludge, which is present in large quantities in a number of storage tanks at Westinghouse Savannah River

  11. Hot dry rock heat mining

    International Nuclear Information System (INIS)

    Duchane, D.V.

    1992-01-01

    Geothermal energy utilizing fluids from natural sources is currently exploited on a commercial scale at sites around the world. A much greater geothermal resource exists, however, in the form of hot rock at depth which is essentially dry. This hot dry rock (HDR) resource is found almost everywhere, but the depth at which usefully high temperatures are reached varies from place to place. The technology to mine the thermal energy from HDR has been under development for a number of years. Using techniques adapted from the petroleum industry, water is pumped at high pressure down an injection well to a region of usefully hot rock. The pressure forces open natural joints to form a reservoir consisting of a small amount of water dispensed in a large volume of hot rock. This reservoir is tapped by second well located at some distance from the first, and the heated water is brought to the surface where its thermal energy is extracted. The same water is then recirculated to mine more heat. Economic studies have indicated that it may be possible to produce electricity at competitive prices today in regions where hot rock is found relatively close to the surface

  12. Spore survival during batch dry rendering of abattoir waste.

    Science.gov (United States)

    Lowry, P D; Fernando, T; Gill, C O

    1979-01-01

    Normal batch dry rendering practice does not ensure sterile products, because bacterial spores are protected against thermal denaturation by the high fat-low water content environment which results from drying the materials at temperatures below those required for sterilization. PMID:117753

  13. DRYING PERFORMANCE AND OVERALL ENERGY REQUISITE OF INDUSTRIAL INCLINED BED PADDY DRYING IN MALAYSIA

    Directory of Open Access Journals (Sweden)

    M. NORDIN IBRAHIM

    2014-06-01

    Full Text Available An attempt was undertaken to evaluate the performance of industrial inclined bed dryers (IBDs in terms of drying capacity, drying rate, overall energy requisite and final quality of dried product in drying of freshly harvested paddy. In drying of paddy with initial moisture content of 22-23% wet basis (wb to around 12.5% (wb final moisture content, drying capacity and drying rate of the dryers were found to vary between 0.66 to 1.03 ton dry paddy/hour and 90 to 121 kg moisture/hour, respectively, for the holding capacity of each dryer at about 15 ton. The electrical energy consumption of the IBDs was found to vary between 18.15 to 27.55 kWh/t while the thermal energy consumption ranged between 960 to 1328.15 MJ/t. The IBDs operated at air temperature of 38-39oC yielded 1 to 4% higher head rice yield than the IBDs were operated at 41-42oC for drying of similar moist paddy, but milling recovery and whiteness were comparable.

  14. Fundamentals of freeze-drying.

    Science.gov (United States)

    Nail, Steven L; Jiang, Shan; Chongprasert, Suchart; Knopp, Shawn A

    2002-01-01

    --the dominant mechanism of heat transfer in freeze-drying--is inefficient at the pressures used in freeze-drying. Steps should be taken to improve the thermal contact between the product and the shelf of the freeze dryer, such as eliminating metal trays from the drying process. Quantitation of the heat transfer coefficient for the geometry used is a useful way of assessing the impact of changes in the system such as elimination of product trays and changes in the vial. Because heat transfer by conduction through the vapor increases with increasing pressure, the commonly held point of view that "the lower the pressure, the better" is not true with respect to process efficiency. The optimum pressure for a given product is a function of the temperature at which freeze-drying is carried out, and lower pressures are needed at low product temperatures. The controlling resistance to mass transfer is almost always the resistance of the partially dried solids above the submination interface. This resistance can be minimized by avoiding fill volumes of more than about half the volume of the container. The development scientist should also recognize that very high concentrations of solute may not be appropriate for optimum freeze-drying, particularly if the resistance of the dried product layer increases sharply with concentration. Although the last 10 years has seen the publication of a significant body of literature of great value in allowing development scientists and engineers to "work smarter," there is still much work needed in both the science and the technology of freeze-drying. Scientific development is needed for improving analytical methodology for characterization of frozen systems and freeze-dried solids. A better understanding of the relationship between molecular mobility and reactivity is needed to allow accurate prediction of product stability at the intended storage temperature based on accelerated stability at higher temperatures. This requires that the temperature

  15. Stability of unpackaged CIGS solar cells under illumination with damp heat, dry heat and dry cold followed by cycling

    NARCIS (Netherlands)

    Theelen, M.; Amorim Soares, G. de; Beyeler, K.; Steijvers, H.; Barreau, N.

    2017-01-01

    Unpackaged CIGS solar cells were simultaneously exposed to illumination and either dry heat, damp heat or dry cold followed by thermal cycling. In-situ monitoring of their electrical parameters demonstrated a rapid decrease of the efficiency for the solar cells exposed to damp heat plus

  16. Heat and mass transfer models to understand the drying mechanisms of a porous substrate.

    Science.gov (United States)

    Songok, Joel; Bousfield, Douglas W; Gane, Patrick A C; Toivakka, Martti

    2016-02-01

    While drying of paper and paper coatings is expensive, with significant energy requirements, the rate controlling mechanisms are not currently fully understood. Two two-dimensional models are used as a first approximation to predict the heat transfer during hot air drying and to evaluate the role of various parameters on the drying rates of porous coatings. The models help determine the structural limiting factors during the drying process, while applying for the first time the recently known values of coating thermal diffusivity. The results indicate that the thermal conductivity of the coating structure is not the controlling factor, but the drying rate is rather determined by the thermal transfer process at the structure surface. This underlines the need for ensuring an efficient thermal transfer from hot air to coating surface during drying, before considering further measures to increase the thermal conductivity of porous coatings.

  17. Effect of probiotic fermented milk (kefir) on glycemic control and lipid profile in type 2 diabetic patients: a randomized double-blind placebo-controlled clinical trial.

    Science.gov (United States)

    Ostadrahimi, Alireza; Taghizadeh, Akbar; Mobasseri, Majid; Farrin, Nazila; Payahoo, Laleh; Beyramalipoor Gheshlaghi, Zahra; Vahedjabbari, Morteza

    2015-02-01

    Diabetes is a global health problem in the world. Probiotic food has anti-diabetic property. The aim of this trial was to determine the effect of probiotic fermented milk (kefir) on glucose and lipid profile control in patients with type 2 diabetes mellitus. This randomized double-blind placebo-controlled clinical trial was conducted on 60 diabetic patients aged 35 to 65 years.Patients were randomly and equally (n=30) assigned to consume either probiotic fermented milk (kefir) or conventional fermented milk (dough) for 8 weeks. Probiotic group consumed 600 ml/day probiotic fermented milk containing Lactobacillus casei, Lactobacillus acidophilus and Bifidobacteria and control group consumed 600 ml/day conventional fermented milk.Blood samples tested for fasting blood glucose, HbA1C, triglyceride (TG), total cholesterol, HDL-C and LDL-C at the baseline and end of the study. The comparison of fasting blood glucose between two groups after intervention was statistically significant (P=0.01). After intervention, reduced HbA1C compared with the baseline value in probiotic fermented milk group was statistically significant (P=0.001), also the HbA1C level significantly decreased in probiotic group in comparison with control group (P=0.02) adjusting for serum levels of glucose, baseline values of HbA1c and energy intake according to ANCOVA model. Serum triglyceride, total cholesterol, LDL-cholesterol and HDL- cholesterol levels were not shown significant differences between and within the groups after intervention. Probiotic fermented milk can be useful as a complementary or adjuvant therapy in the treatment of diabetes.

  18. Drying and energy technologies

    CERN Document Server

    Lima, A

    2016-01-01

    This book provides a comprehensive overview of essential topics related to conventional and advanced drying and energy technologies, especially motivated by increased industry and academic interest. The main topics discussed are: theory and applications of drying, emerging topics in drying technology, innovations and trends in drying, thermo-hydro-chemical-mechanical behaviors of porous materials in drying, and drying equipment and energy. Since the topics covered are inter- and multi-disciplinary, the book offers an excellent source of information for engineers, energy specialists, scientists, researchers, graduate students, and leaders of industrial companies. This book is divided into several chapters focusing on the engineering, science and technology applied in essential industrial processes used for raw materials and products.

  19. Dry etching for microelectronics

    CERN Document Server

    Powell, RA

    1984-01-01

    This volume collects together for the first time a series of in-depth, critical reviews of important topics in dry etching, such as dry processing of III-V compound semiconductors, dry etching of refractory metal silicides and dry etching aluminium and aluminium alloys. This topical format provides the reader with more specialised information and references than found in a general review article. In addition, it presents a broad perspective which would otherwise have to be gained by reading a large number of individual research papers. An additional important and unique feature of this book

  20. through Slicing, DryIng and Packagi.

    African Journals Online (AJOL)

    lene b~gs than in perforated polyethylene bags. lished but in-pack condensation due to high moisture content of ihe 'dry' michembe could be held accountable. This would in tum lead to more activities of-food-bor'ne microorganisms than in the other, types of packaging materials,. Moisture losses in th~ l~,st month could not ...

  1. Effect of solar radiation on drying house performance

    International Nuclear Information System (INIS)

    Rachmat, R.

    2000-01-01

    Solar drying is one of thermal utilization where radiation energy can be utilized efficiently. Solar drying of all sorts of agricultural products have been thoroughly studied and reported in literature, but brown rice drying system has not yet done as many as other products. The aim of the present study is to investigate the effect of solar radiation on drying house performance and brown rice drying characteristics. A construction of drying house is made from FRP sheets with 30 deg. of root slope faces southern part and inside the drying house is installed a flat bed dryer. The site of construction has 136 deg. 31.4'E in longitude and 34 deg. 43.8N in latitude with 3 m in elevation from sea level. The investigated parameters are global solar radiation, absorbed and net radiation and brown rice drying characteristics. The results showed that in unload condition, the air temperature inside drying house was higher (10 deg. C - 12 deg. C) than ambient air when there was not collector and temperature rise become higher (16 deg. C) when there was a black FRP collector inside drying house. The effect of solar radiation on temperature rise has the trend as a linear function. The heat collection efficiency of drying house with black FRP collector was two times higher (36.9 percent) than that without collector (16.3 percent). These phenomena exhibited significant result of collector utilization to the advantageous condition for a drying purpose [in

  2. Solar drying of a solid waste from steel wire industry

    International Nuclear Information System (INIS)

    Ferreira, André Guimarães; Gonçalves, Lindomar Matias; Maia, Cristiana Brasil

    2014-01-01

    The solid residue coming from the treatment of effluents generated in pickling steel wire has an inorganic nature. This residue, after the process of moisture removal by a filter press, has high moisture content 70% wet basis. Transport costs and landfill could be significantly reduced with the products drying. The use of solar energy to promote drying of the residue is technically and economically feasible. Environmental benefits are presented, due to its renewable characteristic and exemption for emission of greenhouse gases. This study aimed to evaluate the drying of industrial solid waste, using an active integrated solar dryer. The thermal properties and the thermal efficiency of operation of the device in different operating conditions were studied. Experimental tests were developed to evaluate the operation of the solar dryer, until a moisture content (wet basis) of 30% is reached. The instantaneous thermal efficiency of the dryer varied from 9.7% to 29.5%. In the drying experiments, the drying efficiency ranged from 5.2% to 7.2%. Thermal efficiencies presented suitable values for air heaters. Nevertheless, drying efficiencies were low, but they can be improved if the load is increased. - Highlights: • A solar dyer was used to dry industrial solid waste. • It was used a renewable source of energy. • Reduction of the product mass reduced transport and disposal costs. • Water activity was reduced from 68% to 11% in about 8 h

  3. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Tips & Prevention News Ask an Ophthalmologist Patient Stories Español Eye Health / Eye Health A-Z Dry Eye ... Eye Treatment What Is Dry Eye? Leer en Español: ¿Qué Es el Ojo Seco? Written By: Kierstan ...

  4. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Tips & Prevention News Ask an Ophthalmologist Patient Stories Español Eye Health / Eye Health A-Z Dry Eye ... Eye Treatment What Is Dry Eye? Leer en Español: ¿Qué es el ojo seco? Written By: Kierstan ...

  5. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Pagan-Duran MD Sep. 01, 2017 Our eyes need tears to stay healthy and comfortable. If your eyes do not produce enough tears, it is called dry eye. Dry eye is also when your eyes do not make the right type of tears or tear film . How do tears ...

  6. A Comparative Study of the Drying Rate Constant, Drying Efficiency ...

    African Journals Online (AJOL)

    The adoption of the drying techniques would ensure steady availability of these vegetables all the year round as well as reduce carbon emissions from the conventional drying methods and hence mitigate global warming. KEYWORDS: Solar drying, open- air sun drying, drying rate constant, falling rate, climate change, food ...

  7. Collision cross sections and transport coefficients of O-, O2 -, O3 - and O4 - negative ions in O2, N2 and dry air for non-thermal plasmas modelling

    Science.gov (United States)

    Hennad, Ali; Yousfi, Mohammed

    2018-02-01

    The ions interaction data such as interaction potential parameters, elastic and inelastic collision cross sections and the transport coefficients (reduced mobility and diffusion coefficients) have been determined and analyzed in the case of the main negative oxygen ions (O-, O2 -, O3 - and O4 -) present in low temperature plasma at atmospheric pressure when colliding O2, N2 and dry air. The ion transport has been determined from an optimized Monte Carlo simulation using calculated elastic and experimentally fitted inelastic collision cross sections. The elastic momentum transfer collision cross sections have been calculated from a semi-classical JWKB approximation based on a ( n-4) rigid core interaction potential model. The cross sections sets involving elastic and inelastic processes were then validated using measured reduced mobility data and also diffusion coefficient whenever available in the literature. From the sets of elastic and inelastic collision cross sections thus obtained for the first time for O3-/O2, O2 -/N2, O3 -/N2, and O4 -/N2 systems, the ion transport coefficients were calculated in pure gases and dry air over a wide range of the density reduced electric field E/N.

  8. What Is Dry Eye?

    Medline Plus

    Full Text Available ... the Inside of Your Eyelid Nov 29, 2017 New Dry Eye Treatment is a Tear-Jerker Jul ... Privacy Policy Terms of Service For Advertisers For Media Ophthalmology Job Center © American Academy of Ophthalmology 2018 ...

  9. Freeze drying method

    International Nuclear Information System (INIS)

    Coppa, N.V.; Stewart, P.; Renzi, E.

    1999-01-01

    The present invention provides methods and apparatus for freeze drying in which a solution, which can be a radioactive salt dissolved within an acid, is frozen into a solid on vertical plates provided within a freeze drying chamber. The solid is sublimated into vapor and condensed in a cold condenser positioned above the freeze drying chamber and connected thereto by a conduit. The vertical positioning of the cold condenser relative to the freeze dryer helps to help prevent substances such as radioactive materials separated from the solution from contaminating the cold condenser. Additionally, the system can be charged with an inert gas to produce a down rush of gas into the freeze drying chamber to also help prevent such substances from contaminating the cold condenser

  10. Cold Vacuum Drying Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Located near the K-Basins (see K-Basins link) in Hanford's 100 Area is a facility called the Cold Vacuum Drying Facility (CVDF).Between 2000 and 2004, workers at the...

  11. Force convective solar drying system

    International Nuclear Information System (INIS)

    Ruslan, M.H.; Othman, M.Y.; Baharuddin Yatim; Kamaruzzaman Sopian; Ibarahim, Z.

    2006-01-01

    This paper presents design and performance of V-groove back-pass solar collector for solar drying system. In this study three V-groove back-pass solar collector each with dimension of 4.6 m x 1.0 m x 0.15 m have been fabricated for solar drying system. An outdoor test at mean solar intensity for 600-800 Wm -2 by using 0.15m 3 s -1 of air flow rate which also been suggested by (Zeroul et al. 1994) was carried out at Solar Research Energy Park. Universiti Kebangsaan Malaysia. Analysis on the collector performance based on daily data was reported that the value of FR ) e and FRUL was 0.709 ± 0.001 and 5.89 ± 0.31 Wm -2o C -1 respectively with 60-70 o C of output temperature (Ruslan et al. 2001). The three V-groove collectors each with dimension 4.6 m x 0.15 m were connected in series array mounted on the roof of a solar assisted drying system. By using two electric fans of 85W and 2700 rpm each, the speed of air was regulated at 0.11 kgs -1 to 0.31 kgs -1 using a voltage regulator. Performance of the collector based on the thermal analysis showed that at mean daily solar radiation 700 Wm -2 , the output temperature of 52 o C to 73 o C could be achieved using 0.11-0.31 kgs -1 of flow rate. Thermal analysis also showed that the efficiencies of 45% to 61% could be obtains using the same flow rate and solar radiation. Analysis of daily data showed that for radiation from 300 Wm -2 to 1000 Wm -2 the power generated from the collector was within 1.5 kW to 8.9 kW. The study concluded that the levels of the levels of the solar radiation and flow rate used influenced the performance of the collector

  12. Porcelain tiles by the dry route

    International Nuclear Information System (INIS)

    Melchiades, F. G.; Daros, M. T.; Boschi, A. O.

    2010-01-01

    In Brazil, the second largest tile producer of the world, at present, 70% of the tiles are produced by the dry route. One of the main reasons that lead to this development is the fact that the dry route uses approximately 30% less thermal energy them the traditional wet route. The increasing world concern with the environment and the recognition of the central role played by the water also has pointed towards privileging dry processes. In this context the objective of the present work is to study the feasibility of producing high quality porcelain tiles by the dry route. A brief comparison of the dry and wet route, in standard conditions industrially used today to produce tiles that are not porcelain tiles, shows that there are two major differences: the particle sizes obtained by the wet route are usually considerably finer and the capability of mixing the different minerals, the intimacy of the mixture, is also usually better in the wet route. The present work studied the relative importance of these differences and looked for raw materials and operational conditions that would result in better performance and glazed porcelain tiles of good quality. (Author) 7 refs.

  13. Porcelain tiles by the dry route

    Energy Technology Data Exchange (ETDEWEB)

    Melchiades, F. G.; Daros, M. T.; Boschi, A. O.

    2010-07-01

    In Brazil, the second largest tile producer of the world, at present, 70% of the tiles are produced by the dry route. One of the main reasons that lead to this development is the fact that the dry route uses approximately 30% less thermal energy them the traditional wet route. The increasing world concern with the environment and the recognition of the central role played by the water also has pointed towards privileging dry processes. In this context the objective of the present work is to study the feasibility of producing high quality porcelain tiles by the dry route. A brief comparison of the dry and wet route, in standard conditions industrially used today to produce tiles that are not porcelain tiles, shows that there are two major differences: the particle sizes obtained by the wet route are usually considerably finer and the capability of mixing the different minerals, the intimacy of the mixture, is also usually better in the wet route. The present work studied the relative importance of these differences and looked for raw materials and operational conditions that would result in better performance and glazed porcelain tiles of good quality. (Author) 7 refs.

  14. Thermal evolution of the crystal structure of proton conducting BaCe0.8Y0.2O3-δ from high-resolution neutron diffraction in dry and humid atmosphere.

    Science.gov (United States)

    Eriksson Andersson, Annika K; Selbach, Sverre M; Grande, Tor; Knee, Christopher S

    2015-06-21

    The crystal structure of the proton conducting perovskite BaCe(0.8)Y(0.2)O(3-δ) (BCY20) has been studied via high-resolution in situ neutron diffraction performed in controlled dry and humid (heavy water) oxygen flow. Two phase transitions, cubic Pm3[combining macron]m→R3[combining macron]c (775 °C)→Imma (250 °C) were observed on cooling from 1000 °C in dry O(2). A significant shift of the phase stability fields was observed on cooling in wet oxygen (pD(2)O ≈ 0.2 atm) with the R3[combining macron]c structure stabilised at 900 °C, and the R3[combining macron]c→Imma transition occurring at 675 °C. On cooling below 400 °C a monoclinic, I2/m, phase started to appear. The structural dependence on hydration level is primarily due to the de-stabilisation of the correlated, octahedra tilts as a consequence of structural relaxation around the oxygen vacancies present in the non-hydrated phase. The tendency of hydrated BaCe(0.8)Y(0.2)O(3-δ) to show octahedral tilting is also found to be enhanced, indicating that the deuteronic (protonic) defects influence the crystal structure, possibly via hydrogen bonding. Stabilisation of the monoclinic I2/m phase is attributed to the structural effect of deuterons that is inferred to increase on cooling as deuterons localise to a greater extent. Changing from wet oxidising (O(2) + D2O(g)) to wet reducing (5% H2 in Ar + D2O(g)) atmosphere did not influence the structure or the phase stability, indicating that Ce(4+) was not reduced under the present conditions. Based on the observed cell volume expansion protonic defects are present in the material at 900 °C at a D(2)O partial pressure of ∼0.2 atm. The origin of the chemical expansion is explained by the effective size of the oxygen vacancy being significantly smaller than the [OD] defect. Rietveld analysis has been used to locate possible sites for the deuterons in the high temperature, R3[combining macron]c and Imma, phases that are most relevant for proton transport.

  15. A full size test rig of dry and dry-wet towers

    International Nuclear Information System (INIS)

    Fesson, J.-P.

    1981-01-01

    In order to test the various systems submitted by French companies, with a view to their application to the 900 MW and 1300 MW nuclear units, the tower is divided into two parts, each permitting the evacuation of an identical thermal charge. The first part includes a cross-current wet zone in which the water flows vertically and the air horizontally, connected to a set of vertical dry batteries. The second part includes bands of packing along the counter-current system, alternating with horizontal dry exchangers [fr

  16. Cassava Sun Drying Performance on Various Surfaces and Drying ...

    African Journals Online (AJOL)

    depth and recommended for sun drying of cassava. However; there is need to investigate on whether there is significant quality difference between cassava sun dried at different bed depths investigated in this study. Key words: drying characteristics, weight loss, ambient air temperature, perforated surface, cassava drying ...

  17. Effect of drying methods on total antioxidant capacity of bitter gourd (momordica charantia) fruit

    Science.gov (United States)

    Tan, Ee Shian; Abdullah, Aminah; Maskat, Mohammad Yusof

    2013-11-01

    The effect of thermal and non-thermal drying methods on hydrophilic and lipophilic antioxidant capacities of bitter gourd fruit was investigated in this study. The bitter gourd fruits were dried by following methods: (i) oven drying 40°C, (ii) oven drying 50°C, (iii) oven drying 60°C, (iv) microwave drying (medium low power), (v) microwave drying (medium power) and (vi) freeze drying. Pure acetone and hexane were used to extract the hydrophilic and lipophilic antioxidant compounds from dried bitter gourd fruits. Freeze dried extracts reported to have highest values in DPPH scavenging activity (hydrophilic and lipophilic fractions), FRAP (lipophilic fraction) and TPC (hydrophilic and lipophilic fraction). Thermal drying slightly increased the values of DPPH scavenging activity, FRAP and TPC assays for hydrophilic extracts. Results concluded bitter gourd fruit is a good source of natural antioxidants and its total antioxidant quality was most preserved by freeze drying. Additionally, the higher value reported in DPPH scavenging activity, FRAP and TPC assays for lipophilic extracts than the hydrophilic extracts suggested that the lipophilic antioxidant compounds of bitter gourd fruit might possess stronger antioxidant power than its counterpart.

  18. Trigger Point Dry Needling.

    Science.gov (United States)

    2017-03-01

    Increasingly, physical therapists in the United States and throughout the world are using dry needling to treat musculoskeletal pain, even though this treatment has been a controversial addition to practice. To better generalize to physical therapy practice the findings about dry needling thus far, the authors of a study published in the March 2017 issue of JOSPT identified the need for a systematic review examining the effectiveness of dry needling performed by physical therapists on people with musculoskeletal pain. Their review offers a meta-analysis of data from several included studies and assesses the evidence for risks of bias. J Orthop Sports Phys Ther 2017;47(3):150. doi:10.2519/jospt.2017.0502.

  19. Drying of Concrete

    DEFF Research Database (Denmark)

    Hansen, Kurt Kielsgaard; Geiker, Mette Rica; Nygaard, Peter Vagn

    2002-01-01

    Estimated and measured relative humidity (RH) change during drying are compared for two concretes, 1: w/c=0.46 and 2: w/(c+0.5fa+2sf)=0.50. The estimations were undertaken by means of the Swedish program TorkaS 1.0. Measurements were performed by RH-sensors type Humi-Guard. Drying of 150 mm thick...... samples from sides at 60% RH and 22 °C took place from 4 to 56 days after casting. At the end of the drying period the measured RH was about 4% lower than the estimated RH at 1/5th depth from the exposed surface for both concretes. In the middle of the samples, the measured RH of concretes 1 and 2 were 2...

  20. Experience in waste drying

    International Nuclear Information System (INIS)

    Burnham, R.E.; Temus, C.J.; Hillstrom, D.S.

    1987-01-01

    Ion exchange resins, filter media and sludges are currently either dewatered or solidified for stabilization, prior to disposal at a low level waste facility. Nuclear Packaging developed the Resin Drying System and placed it into commercial service to provide a system which meets the regulatory requirements for free standing water with a relatively short process duration, requiring no chemical or material addition and utilizing more volume efficient containers than were previously available. The Resin Drying System has proven to be a very cost effective, efficient and secure means of processing low level radioactive waste for many utilities in the United States

  1. Identification and Characterization of Oleaginous Yeast Isolated from Kefir and Its Ability to Accumulate Intracellular Fats in Deproteinated Potato Wastewater with Different Carbon Sources

    Science.gov (United States)

    Kieliszek, Marek; Jermacz, Karolina; Błażejak, Stanisław

    2017-01-01

    The search for efficient oleaginous microorganisms, which can be an alternative to fossil fuels and biofuels obtained from oilseed crops, has been going on for many years. The suitability of microorganisms in this regard is determined by their ability to biosynthesize lipids with preferred fatty acid profile along with the concurrent utilization of energy-rich industrial waste. In this study, we isolated, characterized, and identified kefir yeast strains using molecular biology techniques. The yeast isolates identified were Candida inconspicua, Debaryomyces hansenii, Kluyveromyces marxianus, Kazachstania unispora, and Zygotorulaspora florentina. We showed that deproteinated potato wastewater, a starch processing industry waste, supplemented with various carbon sources, including lactose and glycerol, is a suitable medium for the growth of yeast, which allows an accumulation of over 20% of lipid substances in its cells. Fatty acid composition primarily depended on the yeast strain and the carbon source used, and, based on our results, most of the strains met the criteria required for the production of biodiesel. In particular, this concerns a significant share of saturated fatty acids, such as C16:0 and C18:0, and unsaturated fatty acids, such as C18:1 and C18:2. The highest efficiency in lipid biosynthesis exceeded 6.3 g L−1. Kazachstania unispora was able to accumulate the high amount of palmitoleic acid. PMID:29098157

  2. Effects of heat, cold, acid and bile salt adaptations on the stress tolerance and protein expression of kefir-isolated probiotic Lactobacillus kefiranofaciens M1.

    Science.gov (United States)

    Chen, Ming-Ju; Tang, Hsin-Yu; Chiang, Ming-Lun

    2017-09-01

    Lactobacillus kefiranofaciens M1 is a probiotic strain isolated from Taiwanese kefir grains. The present study evaluated the effects of heat, cold, acid and bile salt adaptations on the stress tolerance of L. kefiranofaciens M1. The regulation of protein expression of L. kefiranofaciens M1 under these adaptation conditions was also investigated. The results showed that adaptation of L. kefiranofaciens M1 to heat, cold, acid and bile salts induced homologous tolerance and cross-protection against heterologous challenge. The extent of induced tolerance varied depending on the type and condition of stress. Proteomic analysis revealed that 27 proteins exhibited differences in expression between non-adapted and stress-adapted L. kefiranofaciens M1 cells. Among these proteins, three proteins involved in carbohydrate metabolism (triosephosphate isomerase, enolase and NAD-dependent glycerol-3-phosphate dehydrogenase), two proteins involved in pH homeostasis (ATP synthase subunits AtpA and AtpB), two stress response proteins (chaperones DnaK and GroEL) and one translation-related protein (30S ribosomal protein S2) were up-regulated by three of the four adaptation treatments examined. The increased synthesis of these stress proteins might play a critical protective role in the cellular defense against heat, cold, acid and bile salt stresses. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Effect of whey goat milk kefir on hydrophobicity of E. coli O157:H7, S. typhi bacteria and C. albicans

    Directory of Open Access Journals (Sweden)

    Dedi Fardiaz

    2012-03-01

    Full Text Available The hydrophobicity of bacteria. was determined using BATH (Bacteria adhesion to hydrocarbon test. All bacteria showed that 0,9 ml n-octane exposure gave a positive response and indicating that E. coli O157:H7 was categorized as moderate hydrophobic bacteria,  while S.  typhi  and C. albicans were catagorized as  highly hydrophobic bacteria. Goat Milk Kefir increased hydrophobicity of E.  coli O157:H7 by 24.40, however, decreased hydrophobicity of S. typhi by 47.56  and C. albicans by 70.14 percent, respectively. This finding showed that one of the inhibition mechanism may be caused by  an interaction  of  organic acid and peptide  compounds with cell membrane, in which hydrophobic sites of component  modified the hydrophobicity of the bacteria cell surface. The hydrophobicity modification in bacterial  cell wall might result inhibition of adhetion bacteria at cell host. Key words : Enterophatogenic bacteria, hidrophobisitas bacteria

  4. A Lactobacillus plantarum strain isolated from kefir protects against intestinal infection with Yersinia enterocolitica O9 and modulates immunity in mice.

    Science.gov (United States)

    De Montijo-Prieto, Soumi; Moreno, Encarnación; Bergillos-Meca, Triana; Lasserrot, Agustín; Ruiz-López, María-Dolores; Ruiz-Bravo, Alfonso; Jiménez-Valera, María

    2015-10-01

    Lactobacillus plantarum C4, previously isolated from kefir and characterized as a potential probiotic strain, was tested for its protective and immunomodulatory capacity in a murine model of yersiniosis. The inoculation of BALB/c mice with a low pathogenicity serotype O9 strain of Yersinia enterocolitica results in a prolonged intestinal infection with colonization of Peyer's patches. Pretreatment with C4 was without effect on fecal excretion of yersiniae, but shortened the colonization of Peyer's patches. This protective effect was associated with pro-inflammatory status in the intestinal mucosa (TNF-α production in infected mice was increased by C4) and an increase in total IgA secretion. At a systemic level, C4 did not promote a pro-inflammatory response, although production of the immunoregulatory cytokine IFN-γ was enhanced. These findings suggest that L. plantarum C4 can increase resistance to intestinal infections through its immunomodulatory activity. Copyright © 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  5. Corncob-fueled drying system

    Energy Technology Data Exchange (ETDEWEB)

    Morey, R.V.; Thimsen, D.P.; Lang, J.P.; Hansen, D.J.

    1984-01-01

    A system to collect, transport, process, dry and burn corncobs to dry shelled corn was evaluated. A mixture of shelled corn and cobs was harvested and transported to the drying facility where a continuous, automated system separated, dried and conveyed cobs to the combustor, a two-stage downdraft device with a 400 to 800 kW heat output. Exhaust products were put directly into the drying air without adversely affecting the corn's appearance or odor. 6 references.

  6. FREEZE DRYING PROCESS: A REVIEW

    OpenAIRE

    Soham Shukla

    2011-01-01

    Among the various methods of drying, this article has mentioned only one most important method, “Freeze drying”. This method is mainly used for the drying of thermo labile materials. This method works on the principle of sublimation. This method is divided into 3 steps for its better understanding; these are Freezing, Primary drying, and secondary drying. There are many advantages and disadvantages of this method, but still this is the most useful drying method nowadays.

  7. What Is Dry Eye?

    Medline Plus

    Full Text Available ... tested whether I close my eyes when I sleep? Feb 10, 2016 Can light sensitivity from Parkinson’s be treated? Jan 28, ... of Your Eyelid Nov 29, 2017 New Dry Eye Treatment is a Tear-Jerker Jul 21, 2017 Three ...

  8. Dry Cleaning, Course Description.

    Science.gov (United States)

    Briscoe, Albert J.; Anderson, Floyd L.

    This course description was developed by educators for use at the Work Opportunity Center which was established to teach high school dropouts and/or hard-core unemployed youth. The ultimate objectives of this course are to prepare students for employment in dry cleaning occupations and to assist them in completing their high school graduation…

  9. CARACTERIZAÇÃO DE MICRO-ORGANISMOS COM POTENCIAL PROBIÓTICO ISOLADOS A PARTIR DE KEFIR PRODUZIDOS NA REGIÃO NOROESTE DO ESTADO DO RIO GRANDE DO SUL

    OpenAIRE

    Alice de Souza Ribeiro

    2015-01-01

    O consumo de alimentos funcionais tem aumentando no decorrer dos anos, pela conscientização da população em adquirir alimentos que tragam benefícios à saúde. Dentre os principais e mais consumidos alimentos funcionais estão os leites fermentados. O kefir é um leite fermentado que tem se destacado pela sua origem funcional natural, com efeitos significativos sobre a saúde quando consumido regularmente, e apesar de não ser comercializado no Brasil é encontrado facilmente de forma artesanal. Des...

  10. Infrared Drying Parameter Optimization

    Science.gov (United States)

    Jackson, Matthew R.

    In recent years, much research has been done to explore direct printing methods, such as screen and inkjet printing, as alternatives to the traditional lithographic process. The primary motivation is reduction of the material costs associated with producing common electronic devices. Much of this research has focused on developing inkjet or screen paste formulations that can be printed on a variety of substrates, and which have similar conductivity performance to the materials currently used in the manufacturing of circuit boards and other electronic devices. Very little research has been done to develop a process that would use direct printing methods to manufacture electronic devices in high volumes. This study focuses on developing and optimizing a drying process for conductive copper ink in a high volume manufacturing setting. Using an infrared (IR) dryer, it was determined that conductive copper prints could be dried in seconds or minutes as opposed to tens of minutes or hours that it would take with other drying devices, such as a vacuum oven. In addition, this study also identifies significant parameters that can affect the conductivity of IR dried prints. Using designed experiments and statistical analysis; the dryer parameters were optimized to produce the best conductivity performance for a specific ink formulation and substrate combination. It was determined that for an ethylene glycol, butanol, 1-methoxy 2- propanol ink formulation printed on Kapton, the optimal drying parameters consisted of a dryer height of 4 inches, a temperature setting between 190 - 200°C, and a dry time of 50-65 seconds depending on the printed film thickness as determined by the number of print passes. It is important to note that these parameters are optimized specifically for the ink formulation and substrate used in this study. There is still much research that needs to be done into optimizing the IR dryer for different ink substrate combinations, as well as developing a

  11. Hot Dry Rock Geothermal Energy Development Program

    Energy Technology Data Exchange (ETDEWEB)

    Smith, M.C.; Hendron, R.H.; Murphy, H.D.; Wilson, M.G.

    1989-12-01

    During Fiscal Year 1987, emphasis in the Hot Dry Rock Geothermal Energy Development Program was on preparations for a Long-Term Flow Test'' of the Phase II'' or Engineering'' hot dry rock energy system at Fenton Hill, New Mexico. A successful 30-day flow test of the system during FY86 indicated that such a system would produce heat at a temperature and rate that could support operation of a commercial electrical power plant. However, it did not answer certain questions basic to the economics of long-term operation, including the rate of depletion of the thermal reservoir, the rate of water loss from the system, and the possibility of operating problems during extended continuous operation. Preparations for a one-year flow test of the system to answer these and more fundamental questions concerning hot dry rock systems were made in FY87: design of the required surface facilities; procurement and installation of some of their components; development and testing of slimline logging tools for use through small-diameter production tubing; research on temperature-sensitive reactive chemical tracers to monitor thermal depletion of the reservoir; and computer simulations of the 30-day test, extended to modeling the planned Long-Term Flow Test. 45 refs., 34 figs., 5 tabs.

  12. Refuge behaviour from outdoor thermal environmental stress and seasonal differences of thermal sense in tropical urban climate

    Science.gov (United States)

    Kurazumi, Y.; Ishii, J.; Fukagawa, K.; Kondo, E.; Aruninta, A.

    2017-12-01

    Thermal sensation affects body temperature regulation. As a starting point for behavioral body temperature regulation taken to improve from a poor thermal environment to a more pleasant environment, thermal sense of thermal environment stimulus is important. The poupose of this sutudy is to use the outdoor thermal environment evaluation index ETFe to quantify effects on thermal sensations of the human body of a tropical region climate with small annual temperature differences, and to examine seasonal differences in thermal sensation. It was found temperature preferences were lower in the winter season than in the dry season, and that a tolerance for higher temperatures in the dry season than in the winter season. It was found effects of seasonal differences of the thermal environment appear in quantitative changes in thermal sensations. It was found that effects of seasonal differences of the thermal environment do not greatly affect quantitative changes in thermal comfort.

  13. Standard guide for drying behavior of spent nuclear fuel

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 This guide is organized to discuss the three major components of significance in the drying behavior of spent nuclear fuel: evaluating the need for drying, drying spent nuclear fuel, and confirmation of adequate dryness. 1.1.1 The guide addresses drying methods and their limitations in drying spent nuclear fuels that have been in storage at water pools. The guide discusses sources and forms of water that remain in SNF, its container, or both, after the drying process and discusses the importance and potential effects they may have on fuel integrity, and container materials. The effects of residual water are discussed mechanistically as a function of the container thermal and radiological environment to provide guidance on situations that may require extraordinary drying methods, specialized handling, or other treatments. 1.1.2 The basic issue in drying is to determine how dry the SNF must be in order to prevent issues with fuel retrievability, container pressurization, or container corrosion. Adequate d...

  14. Modelling of nectarine drying under near infrared - Vacuum conditions.

    Science.gov (United States)

    Alaei, Behnam; Chayjan, Reza Amiri

    2015-01-01

    Drying of nectarine slices was performed to determine the thermal and physical properties in order to reduce product deterioration due to chemical reactions, facilitate storage and lower transportation costs. Because nectarine slices are sensitive to heat with long drying period, the selection of a suitable drying approach is a challenging task. Infrared-vacuum drying can be used as an appropriate method for susceptible materials with high moisture content such as nectarine slices. Modelling of nectarine slices drying was carried out in a thin layer near infraredvacuum conditions. Drying of the samples was implemented at the absolute pressures of 20, 40 and 60 kPa and drying temperatures of 50, 60 and 70°C. Drying behaviour of nectarine slices, as well as the effect of drying conditions on moisture loss trend, drying rate, effective diffusion coefficient, activation energy, shrinkage, colour and energy consumption of nectarine slices, dried in near infrared-vacuum dryer are discussed in this study. Six mathematical models were used to predict the moisture ratio of the samples in thin layer drying. The Midilli model had supremacy in prediction of nectarine slices drying behaviour. The maximum drying rates of the samples were between 0.014-0.047 gwater/gdry material·min. Effective moisture diffusivity of the samples was estimated in the ranges of 2.46·10-10 to 6.48·10-10 m2/s. Activation energy were computed between 31.28 and 35.23 kJ/mol. Minimum shrinkage (48.4%) and total colour difference (15.1) were achieved at temperature of 50°C and absolute pressure of 20 kPa. Energy consumption of the tests was estimated in the ranges of 0.129 to 0.247 kWh. Effective moisture diffusivity was increased with decrease of vacuum pressure and increase of drying temperature but effect of drying temperature on effective moisture diffusivity of nectarine slices was more than vacuum pressure. Activation energy was decreased with decrease in absolute pressure. Total colour

  15. Farklı Isıl İşlem Görmüş İnek Sütlerinden Kefir Kültürü ve Tanesi ile Üretilen Kefirlerin Nitelikleri ve Dayanıklılığı Üzerine Araştırmalar

    Directory of Open Access Journals (Sweden)

    Ergin Oktar

    2015-02-01

    Full Text Available Kaynatılmış, pastörize ve sterilize inek sütlerine ayrı ayrı kefir tanesi ve kefir kültürü aşılanarak üretilen kefirlerin depolamanın 1., 6 ve 9. günlerinde fiziksel, kimyasal ve duyusal analizleri yapılmıştır. Kefir örneklerinin depolama süresince pH’ları düşmüş, asitlikleri yükselmiştir. Kefir üretiminde yağ, protein ve laktoz miktarlarında azalma görülmüştür. Depolamada yağ miktarı değişmezken protein ve laktoz miktarında az da olsa azalma görülmüştür. Serbest yağ asitleri gerek üretim gerekse depolama boyunca artış göstermiştir. Tane ile üretilen kefirlerde maya miktarı kültür ile üretilenlere göre daha fazladır. Alkol, asetaldehit ve aseton kefir üretimi sırasında oluşmuş, depolama sırasında artış göstermiştir. Tüm kefir örnekleri depolama süresince duyusal değerlendirmede beğeni kazanmıştır. Kefir kalitesinin; tane ve kültürü aşılama oranına, inkübasyon sıcaklığı ve süresine, katılan sütün bileşim ve uygulanan ısıl işleme bağlı olduğu belirlenmiştir.

  16. a comparative study of the drying rate constant, drying efficiency ...

    African Journals Online (AJOL)

    Vernonia amagdalina) and black pepper (Piper guinenses) using solar dryer and open- air sun drying methods. Two hundred grams (200g) of each sample were dried under the two different conditions. Their respective weight losses were used to ...

  17. Spray Drying Processing: granules production and drying kinetics of droplets

    International Nuclear Information System (INIS)

    Mondragon, R.; Julia, J. E.; Barba, A.; Jarque, J. C.

    2013-01-01

    Spray drying is a unit operation very common in many industrial processes. For each particular application, the resulting granulated material must possess determined properties that depend on the conditions in which the spray drying processing has been carried out, and whose dependence must be known in order to optimize the quality of the material obtained. The large number of variables that influence on the processes of matter and energy transfer and on the formation of granular material has required a detailed analysis of the drying process. Over the years there have been many studies on the spray drying processing of all kind of materials and the influence of process variables on the drying kinetics of the granulated material properties obtained. This article lists the most important works published for both the spray drying processing and the drying of individual droplets, as well as studies aimed at modeling the drying kinetics of drops. (Author)

  18. (6) Oriola thermal paper IJAAR

    African Journals Online (AJOL)

    Adeyinka Odunsi

    Department of Agricultural Engineering, Ladoke Akintola University of Technology, Ogbomoso, Oyo State,. Nigeria. P.M.B.4000, Ogbomoso. E-mail: ... optimization of thermal processing of foods. (Polley et al., 1980). It controls the heat flux in food during processing such as cooking, frying, freezing, drying etc. most of which.

  19. Nitramine Drying & Fine Grinding Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Nitramine Drying and Fine Grinding Facility provides TACOM-ARDEC with a state-of-the-art facility capable of drying and grinding high explosives (e.g., RDX and...

  20. Dry Cleaning Sector (NAICS 8123)

    Science.gov (United States)

    The dry cleaning sector includes establishments engaged in providing laundry services and industrial launderers. Find environmental regulatory information for perchloroethylene (PERC) cleaners as well as hazardous waste regulations for dry cleaners.

  1. Analysis of metabolic activity of lactic acid bacteria and yeast in model kefirs made from goat’s milk and mixtures of goat’s milk with mare’s milk based on changes in electrical conductivity and impedance

    Directory of Open Access Journals (Sweden)

    Dorota Cais-Sokolińska

    2017-01-01

    Full Text Available The aim of this study was to analyse the metabolic activity of lactic acid bacteria and yeast based of changes in electrical conductivity and electrical impedance during fermentation of goat milk and mixtures of goat’s milk and mare’s milk (1:1, 1:2. As a result of fermentation, conductivity increased 1.4-fold. The conductivity of kefir prepared from goat and mare milk mixed at a ratio of 1:2 (6.210 Ω-3∙cm-1 was lower than that of the 1:1 mixture or of goat milk alone (7.242 Ω-3∙cm-1. A significant dependence of electrical conductivity and pH (0.970 ≤ r ≤ 0.993 was recorded during fermentation. The addition of mare milk to goat milk significantly slowed down the growth of LAB (Δλ = 0.8 h and yeasts during kefir production.

  2. Drying hardwoods with impinging jets.

    Science.gov (United States)

    Howard N. Rosen

    1980-01-01

    Silver maple, yellow poplar, and black walnut lumber was dried in a prototype jet dryer over a range of temperatures from 120 degrees to 400 degrees Fahrenheit and air velocities from 1,000 to 9,000 fpm. Different drying schedules were developed for each type of wood. The quality of the jet-dried lumber was good and compared favorably with kiln-dried lumber.

  3. Photopyroelectric measurement of dry matter content in tomato puree concentrates

    NARCIS (Netherlands)

    Neamtu, C.; Dadarlat, D.; Bicanic, D.D.

    2006-01-01

    The photopyroelectric (PPE) method, in both front and back configuration, was used to measure the thermal effusivity and diffusivity of several tomato puree concentrates. These results were used to construct a calibration curve which was used at a later stage to determine dry matter content of

  4. Safety criteria for wet and dry spent fuel storage

    International Nuclear Information System (INIS)

    Vitkova, M.; Gorinov, I.; Dacheva, D.

    2006-01-01

    An overview of the safety criteria for both type of storage (wet and dry) is presented in this paper. The main criteria - thermal, shielding, radiological - are discussed in details. Some requirement to the materials and the operational regimes are also discussed. An attempt for comparison of the safety criteria and general problems for these both type of storage is made

  5. Effect of different drying techniques on the volatile compounds ...

    African Journals Online (AJOL)

    Dried stevia leaf powder was characterized morphologically by scanning electron microscopy while thermal properties were determined by differential scanning calorimetry (DSC). Results: The plant material contained large amounts of spathulenol and caryophyllene oxide. The main compounds were 1-docosanol and ...

  6. Fluid flow in drying drops

    NARCIS (Netherlands)

    Gelderblom, Hanneke

    2013-01-01

    When a suspension drop evaporates, it leaves behind a drying stain. Examples of these drying stains encountered in daily life are coffee or tea stains on a table top, mineral rings on glassware that comes out of the dishwasher, or the salt deposits on the streets in winter. Drying stains are also

  7. Thermal comfort

    CSIR Research Space (South Africa)

    Osburn, L

    2010-01-01

    Full Text Available wider range of temperature limits, saving energy while still satisfying the majority of building occupants. It is also noted that thermal comfort varies significantly between individuals and it is generally not possible to provide a thermal environment...

  8. Biofuels Drying Process Efficiency Research

    Directory of Open Access Journals (Sweden)

    Osvaldas Šlepikas

    2014-02-01

    Full Text Available The paper deals with biofuel drying process efficiency opportunities.Research was carried out with a special stand and performingexperiments. Experimental rig consists of an ultrasonic generator,ultrasonic transducer, a drying chamber and the humidity,temperature gauge. Tests were used for wood pellets. During theexperiment, they were irrigated with water, dried with hot air andadditionally exposed to different frequency ultrasonic vibrations.The tests results have showed that the convective drying processis combined with the ultrasonic vibrations, the drying time isreduced, which means a positive impact on the ultrasonic process.Studies have confirmed that the effectiveness of convectivedrying method combined with operating ultrasonic vibrationsincreases.

  9. Drying and decontamination of pistachios with sequential infrared drying, tempering and hot air drying

    Science.gov (United States)

    The pistachio industry is in need of improved drying technology as the current hot air drying has low energy efficiency and drying rate and high labor cost and also does not produce safe products against microbial contamination. In the current study, dehulled and water- sorted pistachios with a mois...

  10. Effect of paddy drying depth using open-sun drying on drying time ...

    African Journals Online (AJOL)

    The smallholder rice farmers in the Uganda dry their paddy using open-sun drying method. In most cases the paddy is badly dried and has very high fissure levels. Such paddy on milling contributes to low levels of mill recovery and whole grain in the milled rice. This study was therefore done to find a recommendable ...

  11. Dry EEG Electrodes

    Directory of Open Access Journals (Sweden)

    M. A. Lopez-Gordo

    2014-07-01

    Full Text Available Electroencephalography (EEG emerged in the second decade of the 20th century as a technique for recording the neurophysiological response. Since then, there has been little variation in the physical principles that sustain the signal acquisition probes, otherwise called electrodes. Currently, new advances in technology have brought new unexpected fields of applications apart from the clinical, for which new aspects such as usability and gel-free operation are first order priorities. Thanks to new advances in materials and integrated electronic systems technologies, a new generation of dry electrodes has been developed to fulfill the need. In this manuscript, we review current approaches to develop dry EEG electrodes for clinical and other applications, including information about measurement methods and evaluation reports. We conclude that, although a broad and non-homogeneous diversity of approaches has been evaluated without a consensus in procedures and methodology, their performances are not far from those obtained with wet electrodes, which are considered the gold standard, thus enabling the former to be a useful tool in a variety of novel applications.

  12. Characterization of In-Drum Drying Products

    International Nuclear Information System (INIS)

    Kroselj, V.; Jankovic, M.; Skanata, D.; Medakovic, S.; Harapin, D.; Hertl, B.

    2006-01-01

    A few years ago Krsko NPP decided to introduce In-Drum Drying technology for treatment and conditioning of evaporator concentrates and spent ion resins. The main reason to employ this technology was the need for waste volume reduction and experience with vermiculite-cement solidification that proved inadequate for Krsko NPP. Use of In-Drum Drying technology was encouraged by good experience in the field at some German and Spanish NPP's. In the paper, solidification techniques in vermiculite-cement matrix and In-Drum Drying System are described briefly. The resulting waste forms (so called solidification and dryer products) and containers that are used for interim storage of these wastes are described as well. A comparison of the drying versus solidification technology is performed and advantages as well as disadvantages are underlined. Experience gained during seven years of system operation has shown that crying technology resulted in volume reduction by factor of 20 for evaporator concentrates, and by factor of 5 for spent ion resin. Special consideration is paid to the characterization of dryer products. For evaporator concentrates the resulting waste form is a solid salt block with up to 5% bound water. It is packaged in stainless steel drums (net volume of 200 l) with bolted lids and lifting rings. The fluidized spent ion resins (primary and blow-down) are sluiced into the spent resin drying tank. The resin is dewatered and dried by electrical jacket heaters. The resulting waste (i.e. fine granulates) is directly discharged into a shielded stainless steel drum with bolted lid and lifting rings. Characterization of both waste forms has been performed in accordance with recommendations given in Characterization of Radioactive Waste Forms and Packages issued by International Atomic Energy Agency, 1997. This means that radiological, chemical, physical, mechanical, biological and thermal properties of the waste form has been taken into consideration. In the paper

  13. Transfers in porous medium, drying; Transferts en milieu poreux, sechage

    Energy Technology Data Exchange (ETDEWEB)

    Ferrasse, J.H.; Arlabosse, P.; Puaux, J.P. [Ecole des Mines d' Albi-Carnaux, Centre Energetique Environnement, 81 - Albi (France)] (and others)

    2000-07-01

    This congress, on thermology, took place at Lyon in France, the 15-17 may 2000 with a presentation of 143 papers on the recent researches and specialized discussions. The talks published in this book are sorted out in ten thema. One of the thema concerns the transfers in porous medium and the drying, with seven talks presented. They can be applied to many natural domains as the residual waters filtering, the hydrocarbons extraction, the soil utilization for energy source or reserve, the thermal insulation improvement. In the drying domain, two papers are presented, one on the development of the drying of sewage sludges, the other on a drying process for superheated steam. (A.L.B.)

  14. Temozolomide-Based Dry Powder Formulations for Lung Tumor-Related Inhalation Treatment.

    OpenAIRE

    Wauthoz, Nathalie; Deleuze, Philippe; Saumet, Amandine; Duret, Christophe; Kiss, Robert; Amighi, Karim

    2010-01-01

    PURPOSE: Temozolomide dry powder formulations for inhalation, performed with no excipient or with a lipid or lactose coating, have been evaluated. METHODS: The particle size of raw temozolomide in suspension was reduced by a high-pressure homogenizing technique, and the solvent was evaporated by spray-drying to obtain a dry powder. The physicochemical properties of this powder were evaluated and included its crystalline state, thermal properties, morphology, particle size and moisture and dru...

  15. Degradation Characterization of Thermal Interface Greases: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    DeVoto, Douglas J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Major, Joshua [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Paret, Paul P [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Blackman, G. S. [DuPont Experimental Station; Wong, A. [DuPont Experimental Station; Meth, J. S. [DuPont Experimental Station

    2017-08-03

    Thermal interface materials (TIMs) are used in power electronics packaging to minimize thermal resistance between the heat generating component and the heat sink. Thermal greases are one such class. The conformability and thin bond line thickness (BLT) of these TIMs can potentially provide low thermal resistance throughout the operation lifetime of a component. However, their performance degrades over time due to pump-out and dry-out during thermal and power cycling. The reliability performance of greases through operational cycling needs to be quantified to develop new materials with superior properties. NREL, in collaboration with DuPont, has performed thermal and reliability characterization of several commercially available thermal greases. Initial bulk and contact thermal resistance of grease samples were measured, and then the thermal degradation that occurred due to pump-out and dry-out during temperature cycling was monitored. The thermal resistances of five different grease materials were evaluated using NREL's steady-state thermal resistance tester based on the ASTM test method D5470. Greases were then applied, utilizing a 2.5 cm x 2.5 cm stencil, between invar and aluminum plates to compare the thermomechanical performance of the materials in a representative test fixture. Scanning Acoustic microscopy, thermal, and compositional analyses were performed periodically during thermal cycling from -40 degrees Celcius to 125 degrees Celcius. Completion of this characterization has allowed for a comprehensive evaluation of thermal greases both for their initial bulk and contact thermal performance, as well as their degradation mechanisms under accelerated thermal cycling conditions.

  16. Degradation Characterization of Thermal Interface Greases

    Energy Technology Data Exchange (ETDEWEB)

    Major, Joshua [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Narumanchi, Sreekant V [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Paret, Paul P [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Blackman, Gregory [DuPont; Wong, Arnold [DuPont; Meth, Jeffery [DuPont

    2018-02-12

    Thermal interface materials (TIMs) are used in power electronics packaging to minimize thermal resistance between the heat generating component and the heat sink. Thermal greases are one such class. The conformability and thin bond line thickness (BLT) of these TIMs can potentially provide low thermal resistance throughout the operation lifetime of a component. However, their performance degrades over time due to pump-out and dry-out during thermal and power cycling. The reliability performance of greases through operational cycling needs to be quantified to develop new materials with superior properties. NREL, in collaboration with DuPont, has performed thermal and reliability characterization of several commercially available thermal greases. Initial bulk and contact thermal resistance of grease samples were measured, and then the thermal degradation that occurred due to pump-out and dry-out during temperature cycling was monitored. The thermal resistances of five different grease materials were evaluated using NREL's steady-state thermal resistance tester based on the ASTM test method D5470. Greases were then applied, utilizing a 2.5 cm x 2.5 cm stencil, between invar and aluminum plates to compare the thermomechanical performance of the materials in a representative test fixture. Scanning Acoustic microscopy, thermal, and compositional analyses were performed periodically during thermal cycling from -40 degrees C to 125 degrees C. Completion of this characterization has allowed for a comprehensive evaluation of thermal greases both for their initial bulk and contact thermal performance, as well as their degradation mechanisms under accelerated thermal cycling conditions.

  17. Hot Dry Rock; Geothermal Energy

    Energy Technology Data Exchange (ETDEWEB)

    None

    1990-01-01

    The commercial utilization of geothermal energy forms the basis of the largest renewable energy industry in the world. More than 5000 Mw of electrical power are currently in production from approximately 210 plants and 10 000 Mw thermal are used in direct use processes. The majority of these systems are located in the well defined geothermal generally associated with crustal plate boundaries or hot spots. The essential requirements of high subsurface temperature with huge volumes of exploitable fluids, coupled to environmental and market factors, limit the choice of suitable sites significantly. The Hot Dry Rock (HDR) concept at any depth originally offered a dream of unlimited expansion for the geothermal industry by relaxing the location constraints by drilling deep enough to reach adequate temperatures. Now, after 20 years intensive work by international teams and expenditures of more than $250 million, it is vital to review the position of HDR in relation to the established geothermal industry. The HDR resource is merely a body of rock at elevated temperatures with insufficient fluids in place to enable the heat to be extracted without the need for injection wells. All of the major field experiments in HDR have shown that the natural fracture systems form the heat transfer surfaces and that it is these fractures that must be for geothermal systems producing from naturally fractured formations provide a basis for directing the forthcoming but, equally, they require accepting significant location constraints on HDR for the time being. This paper presents a model HDR system designed for commercial operations in the UK and uses production data from hydrothermal systems in Japan and the USA to demonstrate the reservoir performance requirements for viable operations. It is shown that these characteristics are not likely to be achieved in host rocks without stimulation processes. However, the long term goal of artificial geothermal systems developed by systematic

  18. Dry aging of beef; Review

    Directory of Open Access Journals (Sweden)

    Dashmaa Dashdorj

    2016-05-01

    Full Text Available Abstract The present review has mainly focused on the specific parameters including aging (aging days, temperature, relative humidity, and air flow, eating quality (flavor, tenderness and juiciness, microbiological quality and economic (shrinkage, retail yields and cost involved beef dry aging process. Dry aging is the process where beef carcasses or primal cuts are hanged and aged for 28 to 55 d under controlling environment conditions in a refrigerated room with 0° to 4 °C and with relative humidity of 75 to 80 %. However there are various opinions on dry aging procedures and purveyors of such products are passionate about their programs. Recently, there has been an increased interest in dry aging process by a wider array of purveyors and retailers in the many countries. Dry aging process is very costly because of high aging shrinkage (6 to15 %, trims loss (3 to 24 %, risk of contamination and the requirement of highest grades meat with. The packaging in highly moisture-permeable bag may positively impact on safety, quality and shelf stability of dry aged beef. The key effect of dry aging is the concentration of the flavor that can only be described as “dry-aged beef”. But the contribution of flavor compounds of proteolysis and lipolysis to the cooked dry aged beef flavor is not fully known. Also there are limited scientific studies of aging parameters on the quality and palatability of dry aged beef.

  19. Dry aging of beef; Review.

    Science.gov (United States)

    Dashdorj, Dashmaa; Tripathi, Vinay Kumar; Cho, Soohyun; Kim, Younghoon; Hwang, Inho

    2016-01-01

    The present review has mainly focused on the specific parameters including aging (aging days, temperature, relative humidity, and air flow), eating quality (flavor, tenderness and juiciness), microbiological quality and economic (shrinkage, retail yields and cost) involved beef dry aging process. Dry aging is the process where beef carcasses or primal cuts are hanged and aged for 28 to 55 d under controlling environment conditions in a refrigerated room with 0° to 4 °C and with relative humidity of 75 to 80 %. However there are various opinions on dry aging procedures and purveyors of such products are passionate about their programs. Recently, there has been an increased interest in dry aging process by a wider array of purveyors and retailers in the many countries. Dry aging process is very costly because of high aging shrinkage (6 to15 %), trims loss (3 to 24 %), risk of contamination and the requirement of highest grades meat with. The packaging in highly moisture-permeable bag may positively impact on safety, quality and shelf stability of dry aged beef. The key effect of dry aging is the concentration of the flavor that can only be described as "dry-aged beef". But the contribution of flavor compounds of proteolysis and lipolysis to the cooked dry aged beef flavor is not fully known. Also there are limited scientific studies of aging parameters on the quality and palatability of dry aged beef.

  20. DRI Renewable Energy Center (REC) (NV)

    Energy Technology Data Exchange (ETDEWEB)

    Hoekman, S. Kent; Broch, Broch; Robbins, Curtis; Jacobson, Roger; Turner, Robert

    2012-12-31

    The primary objective of this project was to utilize a flexible, energy-efficient facility, called the DRI Renewable Energy Experimental Facility (REEF) to support various renewable energy research and development (R&D) efforts, along with education and outreach activities. The REEF itself consists of two separate buildings: (1) a 1200-ft2 off-grid capable house and (2) a 600-ft2 workshop/garage to support larger-scale experimental work. Numerous enhancements were made to DRI's existing renewable power generation systems, and several additional components were incorporated to support operation of the REEF House. The power demands of this house are satisfied by integrating and controlling PV arrays, solar thermal systems, wind turbines, an electrolyzer for renewable hydrogen production, a gaseous-fuel internal combustion engine/generator set, and other components. Cooling needs of the REEF House are satisfied by an absorption chiller, driven by solar thermal collectors. The REEF Workshop includes a unique, solar air collector system that is integrated into the roof structure. This system provides space heating inside the Workshop, as well as a hot water supply. The Workshop houses a custom-designed process development unit (PDU) that is used to convert woody biomass into a friable, hydrophobic char that has physical and chemical properties similar to low grade coal. Besides providing sufficient space for operation of this PDU, the REEF Workshop supplies hot water that is used in the biomass treatment process. The DRI-REEF serves as a working laboratory for evaluating and optimizing the performance of renewable energy components within an integrated, residential-like setting. The modular nature of the system allows for exploring alternative configurations and control strategies. This experimental test bed is also highly valuable as an education and outreach tool both in providing an infrastructure for student research projects, and in highlighting renewable

  1. Effect of various drying bed on thermodynamic characteristics

    Directory of Open Access Journals (Sweden)

    Ali Motevali

    2017-09-01

    Full Text Available In this study thermodynamic parameter and energy consumption in drying of two plant dill and mint in three bed drying including fix, semi fix and fluid with using a hot air drying was investigated. Experimental was conducted in three bed drying including fix, semi fix and fluid and four levels temperature (30, 40, 50 and 60 °C. Maximum energy consumption in dill drying at 40 °C and fluid bed to be 16.41 MJ and minimum energy consumption at 30 °C and fix bed to be 2.77 MJ. Also minimum energy consumption in mint drying at 60 °C and fix bed to be 3.64 MJ and maximum energy consumption at 40 °C and fluid bed to be 28.65 MJ. The highest energy, drying and thermal efficiency for both mint and dill was achieved at 60 °C on the fixed bed, whereas the lowest efficiency was at 40 °C and on the fluidized bed. Also the highest power and specific heat consumption for both mint and dill was achieved at 40 °C on the fluid bed, whereas the lowest efficiency was at 30 °C and on the fluidized bed.

  2. Dry Ice Etches Terrain

    Science.gov (United States)

    2007-01-01

    [figure removed for brevity, see original site] Figure 1 Every year seasonal carbon dioxide ice, known to us as 'dry ice,' covers the poles of Mars. In the south polar region this ice is translucent, allowing sunlight to pass through and warm the surface below. The ice then sublimes (evaporates) from the bottom of the ice layer, and carves channels in the surface. The channels take on many forms. In the subimage shown here (figure 1) the gas from the dry ice has etched wide shallow channels. This region is relatively flat, which may be the reason these channels have a different morphology than the 'spiders' seen in more hummocky terrain. Observation Geometry Image PSP_003364_0945 was taken by the High Resolution Imaging Science Experiment (HiRISE) camera onboard the Mars Reconnaissance Orbiter spacecraft on 15-Apr-2007. The complete image is centered at -85.4 degrees latitude, 104.0 degrees East longitude. The range to the target site was 251.5 km (157.2 miles). At this distance the image scale is 25.2 cm/pixel (with 1 x 1 binning) so objects 75 cm across are resolved. The image shown here has been map-projected to 25 cm/pixel . The image was taken at a local Mars time of 06:57 PM and the scene is illuminated from the west with a solar incidence angle of 75 degrees, thus the sun was about 15 degrees above the horizon. At a solar longitude of 219.6 degrees, the season on Mars is Northern Autumn.

  3. Moisture Distribution and Flow During Drying of Wood and Fiber

    Energy Technology Data Exchange (ETDEWEB)

    Zink-Sharp, Audrey; Hanna, Robert B.

    2001-12-28

    New understanding, theories, and techniques for moisture flow and distribution were developed in this research on wood and wood fiber. Improved understanding of the mechanisms of flake drying has been provided. Observations of flake drying and drying rate curves revealed that rate of moisture loss consisted of two falling rate periods and no constant rate drying period was observed. Convective heat transfer controls the first period, and bound water diffusion controls the second period. Influence of lower drying temperatures on bending properties of wood flakes was investigated. Drying temperature was found to have a significant influence on bending stiffness and strength. A worksheet for calculation of the energy required to dry a single strandboard flake was developed but has not been tested in an industrial setting yet. A more complete understanding of anisotropic transverse shrinkage of wood is proposed based on test results and statistical analysis. A simplified mod el of a wood cell's cross-section was drawn for calculating differential transverse shrinkage. The model utilizes cell wall thickness and microfibrillar packing density and orientation. In spite of some phenomena of cell wall structure not yet understood completely, the results might explain anisotropic transverse shrinkage to a major extent. Boundary layer theory was found useful for evaluating external moisture resistance during drying. Simulated moisture gradients were quire comparable to the actual gradients in dried wood. A mathematical procedure for determining diffusion and surface emission coefficients was also developed. Thermal conductivity models of wood derived from its anatomical structure were created and tested against experimental values. Model estimations provide insights into changes in heat transfer parameters during drying. Two new techniques for measuring moisture gradients created in wood during drying were developed. A new technique that utilizes optical properties of

  4. Evolution of heat in dry rotary swaging

    Science.gov (United States)

    Herrmann, Marius; Liu, Yang; Schenck, Christian; Kuhfuss, Bernd; Ohlsen, Inken

    2017-10-01

    In dry metal forming processes, the heat dissipation is a critical issue. The cooling by the lubricant is missing. The different heat evolution affects the machine and the process and thus the final product. For the machine the thermal expansion is affected and needs to be considered. Also the tools can bear only a maximum heat load before they get damaged. Furthermore, the heat can influence the material properties like the flow stress if it exceeds a critical value. Furthermore, the process forces and the material flow are directly affected. In addition, heat modifies in combination with plastic strain the generated microstructure of the workpiece. If the heat is high enough even positive effects of cold forming like work hardening are drastically decreased. In summary, the heat evolution during lubricated and dry forming processes need to be investigated. The evolution of heat in rotary swaging was investigated with conventional tools and machine settings. This was realized by varying the feeding velocity for the lubricated forming of aluminum tubes (3.3206) and steel tubes (1.0308). Moreover, the steel tubes are also formed with conventional tools by dry rotary swaging. A temperature measurement was integrated inside the tubes during the rotary process. Thus, the heat evolution inside the tube during the process at two different positions was examined. Also the variation between inside the tubes and the surface of the tubes was investigated by measuring the temperature at the surface directly after the forming process. Comparisons between different measured heat evolutions represent the impact of lubrication, feed rate and material. Thus, the practicability and the challenge for dry forming processes are presented.

  5. Thermal Stress

    Science.gov (United States)

    2011-01-01

    and Science in Sports and Exercise 37: 1328--1334. Coris EE, Ramirez AM, and Van Durme DJ (2004) Heat illness in athletes : The dangerous combination...of heat, humidity and exercise. Sports Medicine 34: 9--16. Gordon CJ and Leon LR (2005) Thermal stress and the physiological response to environmental...code) 2011 Book Chapter-Enc. of Environmental Health Thermal Stress L.R. Leon, C.J. Gordon Thermal and Mountain Medicine Division U.S. Research

  6. Drying Spirulina with Foam Mat Drying at Medium Temperature

    Directory of Open Access Journals (Sweden)

    Aji Prasetyaningrum

    2012-10-01

    Full Text Available Spirulina is a single cell blue green microalgae (Cyanobacteria containing many Phytonutrients (Beta-carotene, Chlorophyl, Xanthophyl, Phyocianin using as anti-carcinogen in food. Producing dry spirulina by quick drying process at medium temperature is very important to retain the Phytonutrient quality. Currently, the work is still challenging due to the gel formation that block the water diffusion from inside to the surface.  This research studies the performance of foam-mat drying on production of dry spirulina. In this method the spirulina was mixed with foaming agent (glair/egg albumen, popular as white egg at 2.5% by weight at air velocity 2.2 m/sec. Here, the effect of spirulina thickness and operational temperature on drying time and quality (Beta-carotene and color were observed. The drying time was estimated based on the measurement of water content in spirulina versus time. Result showed that the thicker spirulina, the longer drying time. Conversely, the higher operational temperature, faster drying time. At thickness ranging 1-3 mm and operational temperature below 70oC, the quality of spirulina can fit the market requirement

  7. The antisickling effects of dried fish (tilapia) And dried prawn ...

    African Journals Online (AJOL)

    The antisickling effect of dried fish (Tilapia) and dried prawn (Astacus red) were investigated to ascertain the ability of the extracts of these samples to inhibit polymerisation of sickle cell haemoglobin (HbS), improve the Fe 2+/Fe 3+ ratio and lower the activity of lactate dehydrogenase (LDH) in blood plasma. The samples ...

  8. Cassava Sun Drying Performance on Various Surfaces and Drying ...

    African Journals Online (AJOL)

    The experiments were done using kiroba cassava variety obtained from the University farm, which was peeled and sliced into thin chips (2-3 mm) then sun dried on wire mesh, black polythene, white polythene and woven mat for three days. The material was dried for 8 hours daily after which it was kept indoors overnight.

  9. Market opportunities for solar drying

    International Nuclear Information System (INIS)

    Voskens, R.G.J.H.; Out, P.G.; Schulte, B.

    2000-01-01

    One of the most promising applications for solar heating is the drying of agricultural products. The drying of agricultural products requires large quantities of low temperature air, in many cases, on a year-round basis. Low cost air-based collectors can provide heated air at solar collection efficiencies of 30 to 70%. In 1998/1999 a study was commissioned to better understand the technical and economic potential for solar drying of agricultural products in the world. The practical potential for solar drying was then determined for 59 crops and 22 regions. The world market for solar drying can be divided into three market segments: 1) mechanical drying T 50 deg. C; 3) sun drying. The most promising market for solar drying is generally market segment 1. For this segment the potential amount of energy displaced by solar is in between 216 770 PJ (World-wide). For Western Europe this potential is estimated between 23 88 PJ and for Eastern Europe between 7 and 13 PJ. A different market introduction strategy is required for each market segment. A total of 13 combinations of crops and regions are selected that appear to have the highest practical potential for solar drying. In the Netherlands a programme of activities was carried out by Ecofys and other organisations, to identify and develop the market potential for solar (assisted) drying of agricultural products. A promotional campaign for the use of renewable energy in the (promising) flower bulb sector is planned on a short-term basis to speed up market developments. It can be concluded that there is a large market for solar drying in the World as well as in Europe. (au)

  10. Forward Osmosis Brine Drying

    Science.gov (United States)

    Flynn, Michael; Shaw, Hali; Hyde, Deirdre; Beeler, David; Parodi, Jurek

    2015-01-01

    The Forward Osmosis Brine Drying (FOBD) system is based on a technique called forward osmosis (FO). FO is a membrane-based process where the osmotic potential between brine and a salt solution is equalized by the movement of water from the brine to the salt solution. The FOBD system is composed of two main elements, the FO bag and the salt regeneration system. This paper discusses the results of testing of the FO bag to determine the maximum water recovery ratio that can be attained using this technology. Testing demonstrated that the FO bag is capable of achieving a maximum brine water recovery ratio of the brine of 95%. The equivalent system mass was calculated to be 95 kg for a feed similar to the concentrated brine generated on the International Space Station and 86 kg for an Exploration brine. The results have indicated that the FOBD can process all the brine for a one year mission for between 11% to 10% mass required to bring the water needed to make up for water lost in the brine if not recycled. The FOBD saves 685 kg and when treating the International Space Station brine and it saves 829 kg when treating the Exploration brine. It was also demonstrated that saturated salt solutions achieve a higher water recovery ratios than solids salts do and that lithium chloride achieved a higher water recovery ratio than sodium chloride.

  11. Comparison of different drying methods on the physical properties, bioactive compounds and antioxidant activity of raspberry powders.

    Science.gov (United States)

    Si, Xu; Chen, Qinqin; Bi, Jinfeng; Wu, Xinye; Yi, Jianyong; Zhou, Linyan; Li, Zhaolu

    2016-04-01

    Dehydration has been considered as one of the traditional but most effective techniques for perishable fruits. Raspberry powders obtained after dehydration can be added as ingredients into food formulations such as bakery and dairy products. In this study, raspberry powders obtained by hot air drying (HAD), infrared radiation drying (IRD), hot air and explosion puffing drying (HA-EPD), infrared radiation and microwave vacuum drying (IR-MVD) and freeze drying (FD) were compared on physical properties, bioactive compounds and antioxidant activity. Drying techniques affected the physical properties, bioactive compounds and antioxidant activity of raspberry powders greatly. FD led to significantly higher (P raspberry powder compared with other drying methods. However, thermal drying techniques, especially combined drying methods, were superior to FD in final total polyphenol content, total flavonoid content and antioxidant activity. The combined drying methods, especially IR-MVD, showed the highest total polyphenol content (123.22 g GAE kg(-1) dw) and total flavonoid content (0.30 g CAE kg(-1) dw). Additionally, IR-MVD performed better in antioxidant activity retention. Overall, combined drying methods, especially IR-MVD, were found to result in better quality of raspberry powders among the thermal drying techniques. IR-MVD could be recommended for use in the drying industry because of its advantages in time saving and nutrient retention. © 2015 Society of Chemical Industry.

  12. Studies and research concerning BNFP: spent fuel dry storage studies at the Barnwell Nuclear Fuel Plant

    International Nuclear Information System (INIS)

    Anderson, K.J.

    1980-09-01

    Conceptual designs are presented utilizing the Barnwell Nuclear Fuel Plant for the dry interim storage of spent light water reactor fuel. Studies were conducted to determine feasible approaches to storing spent fuel by methods other than wet pool storage. Fuel that has had an opportunity to cool for several years, or more, after discharge from a reactor is especially adaptable to dry storage since its thermal load is greatly reduced compared to the thermal load immediately following discharge. A thermal analysis was performed to help in determining the feasibility of various spent fuel dry storage concepts. Methods to reject the heat from dry storage are briefly discussed, which include both active and passive cooling systems. The storage modes reviewed include above and below ground caisson-type storage facilities and numerous variations of vault, or hot cell-type, storage facilities

  13. Thermophysiological Properties of Dry and Wet Functional Sportswear Made of Synthetic Fibres

    Directory of Open Access Journals (Sweden)

    Monika Bogusławska – Bączek

    2017-12-01

    Full Text Available In recent times, knitted fabrics made from synthetic fibres are being used increasingly for sportswear. This type of clothing should ensure thermal comfort in all weather conditions, regardless of the activity of the wearer. The most important thermal properties include thermal conductivity and resistance, as well as water vapour permeability. Sportswear often becomes wet (from sweat or due to a humid environment, which can have a signifi cant effect on thermal properties, while most testing methods only perform measurements in a dry state. This paper therefore presents our study of the thermal properties of different types of knitted fabrics in both dry and wet states. The presented research proved that wet knitwear results in a signifi cant loss of thermal comfort. This phenomenon is exacerbated when the moisture content of a material increases, and depends on the structure and filling of tested materials.

  14. Drying a liquid paint layer

    NARCIS (Netherlands)

    Susanto, H.; van de Fliert, B.W.

    2001-01-01

    Subject of this study is the free boundary problem of a liquid layer that is dried by evaporation. Using a Stefan type problem, we model the diffusion driven drying of a layer of liquid paint consisting of resin and solvent. The effect of a small perturbation of the flat boundary is considered. We

  15. Dry release of suspended nanostructures

    DEFF Research Database (Denmark)

    Forsén, Esko Sebastian; Davis, Zachary James; Dong, M.

    2004-01-01

    A dry release method for fabrication of suspended nanostructures is presented. The technique has been combined with an anti-stiction treatment for fabrication of nanocantilever based nanoelectromechanical systems (NEMS). The process combines a dry release method, using a supporting layer of photo...

  16. Thermal conductivity and thermal diffusivity

    International Nuclear Information System (INIS)

    Hust, J.G.

    1983-01-01

    This chapter examines the heat transfer properties of solids, with emphasis on the behavior of pure metals and alloys. Topics considered include electronic conduction, magnetic field effects, lattice conduction, measuring methods, specimen size, uncertainty, thermal anchoring, radial heat loss, thermal conductivity apparatus, thermal diffusivity apparatus, empirical correlations, the Wiedemann-Franz-Lorenz law, Matthiessen's rule, low-temperature correlation, predictive techniques, crystalline dielectrics, and disordered dielectrics. The materials examined include copper, aluminium, binary alloys, structural alloys, and structural composites

  17. Argon used as dry suit insulation gas for cold-water diving

    OpenAIRE

    Vrijdag, Xavier CE; van Ooij, Pieter-Jan AM; van Hulst, Robert A

    2013-01-01

    Background Cold-water diving requires good thermal insulation because hypothermia is a serious risk. Water conducts heat more efficiently compared to air. To stay warm during a dive, the choice of thermal protection should be based on physical activity, the temperature of the water, and the duration of exposure. A dry suit, a diving suit filled with gas, is the most common diving suit in cold water. Air is the traditional dry suit inflation gas, whereas the thermal conductivity of argon is ap...

  18. Argon used as dry suit insulation gas for cold-water diving.

    Science.gov (United States)

    Vrijdag, Xavier Ce; van Ooij, Pieter-Jan Am; van Hulst, Robert A

    2013-06-03

    Cold-water diving requires good thermal insulation because hypothermia is a serious risk. Water conducts heat more efficiently compared to air. To stay warm during a dive, the choice of thermal protection should be based on physical activity, the temperature of the water, and the duration of exposure. A dry suit, a diving suit filled with gas, is the most common diving suit in cold water. Air is the traditional dry suit inflation gas, whereas the thermal conductivity of argon is approximately 32% lower compared to that of air. This study evaluates the benefits of argon, compared to air, as a thermal insulation gas for a dry suit during a 1-h cold-water dive by divers of the Royal Netherlands Navy. Seven male Special Forces divers made (in total) 19 dives in a diving basin with water at 13 degrees C at a depth of 3 m for 1 h in upright position. A rubber dry suit and woollen undergarment were used with either argon (n = 13) or air (n = 6) (blinded to the divers) as suit inflation gas. Core temperature was measured with a radio pill during the dive. Before, halfway, and after the dive, subjective thermal comfort was recorded using a thermal comfort score. No diver had to abort the test due to cold. No differences in core temperature and thermal comfort score were found between the two groups. Core temperature remained unchanged during the dives. Thermal comfort score showed a significant decrease in both groups after a 60-min dive compared to baseline. In these tests the combination of the dry suit and undergarment was sufficient to maintain core temperature and thermal comfort for a dive of 1h in water at 13 degrees C. The use of argon as a suit inflation gas had no added value for thermal insulation compared to air for these dives.

  19. Argon used as dry suit insulation gas for cold-water diving

    Science.gov (United States)

    2013-01-01

    Background Cold-water diving requires good thermal insulation because hypothermia is a serious risk. Water conducts heat more efficiently compared to air. To stay warm during a dive, the choice of thermal protection should be based on physical activity, the temperature of the water, and the duration of exposure. A dry suit, a diving suit filled with gas, is the most common diving suit in cold water. Air is the traditional dry suit inflation gas, whereas the thermal conductivity of argon is approximately 32% lower compared to that of air. This study evaluates the benefits of argon, compared to air, as a thermal insulation gas for a dry suit during a 1-h cold-water dive by divers of the Royal Netherlands Navy. Methods Seven male Special Forces divers made (in total) 19 dives in a diving basin with water at 13°C at a depth of 3 m for 1 h in upright position. A rubber dry suit and woollen undergarment were used with either argon (n = 13) or air (n = 6) (blinded to the divers) as suit inflation gas. Core temperature was measured with a radio pill during the dive. Before, halfway, and after the dive, subjective thermal comfort was recorded using a thermal comfort score. Results No diver had to abort the test due to cold. No differences in core temperature and thermal comfort score were found between the two groups. Core temperature remained unchanged during the dives. Thermal comfort score showed a significant decrease in both groups after a 60-min dive compared to baseline. Conclusions In these tests the combination of the dry suit and undergarment was sufficient to maintain core temperature and thermal comfort for a dive of 1 h in water at 13°C. The use of argon as a suit inflation gas had no added value for thermal insulation compared to air for these dives. PMID:24438580

  20. REDUCING ENVIRONMENTAL IMPACT AND COST OF PRODUCTION FOR DRYING FRUITS

    Directory of Open Access Journals (Sweden)

    Murad Erol

    2013-12-01

    Full Text Available To reduce the production costs for heat used in drying fruit plants was studied using of local biomass from tree branch pruning. The average annual get 3 t / ha biomass whit energy potential of 37 GJ/ha at a cost of up to 60 €/t. biomass at 10 - 50 mm chopped and dried below 20% can be gasefied with TLUD process characterized by high energy conversion efficiency, stability and safety in operation, emissions of CO and PM very low. TLUD process produces on average and 15% biochar that can be used as fuel or as agricultural amendment to increase fertility and for atmospheric carbon sequestration. There have been experiments simulated by model of USCMER 30/60MGB dryer equipped with two thermal modules TLUD FORTE-40 for apple slices drying heat of the apple prinings. Biomass used and biochar resulting chemical and energy were defined as micro-gasification process TLUD. That can dry 205 kg of apple slices in 6 hours with 74 kg of dry biomass to 10% of that remains and 12.2 kg biochar, biochar with or without 52 kg biomass, which costs € 8.55 or € 5.97, ie 4.3 or 6.1 times cheaper than diesel. On dry ton of sliced apple it can produce 59.6 kg biochar with soil seize -174.8 kg. CO2.

  1. Space and Industrial Brine Drying Technologies

    Science.gov (United States)

    Jones, Harry W.; Wisniewski, Richard S.; Flynn, Michael; Shaw, Hali

    2014-01-01

    This survey describes brine drying technologies that have been developed for use in space and industry. NASA has long considered developing a brine drying system for the International Space Station (ISS). Possible processes include conduction drying in many forms, spray drying, distillation, freezing and freeze drying, membrane filtration, and electrical processes. Commercial processes use similar technologies. Some proposed space systems combine several approaches. The current most promising candidates for use on the ISS use either conduction drying with membrane filtration or spray drying.

  2. CMOS Thermal Ox and Diffusion Furnace: Tystar Tytan 2000

    Data.gov (United States)

    Federal Laboratory Consortium — Description:CORAL Names: CMOS Wet Ox, CMOS Dry Ox, Boron Doping (P-type), Phos. Doping (N-Type)This four-stack furnace bank is used for the thermal growth of silicon...

  3. Drying of α-amylase by spray drying and freeze-drying - a comparative study

    Directory of Open Access Journals (Sweden)

    S. S. de Jesus

    2014-09-01

    Full Text Available This study is aimed at comparing two traditional methods of drying of enzymes and at verifying the efficiency of each one and their advantages and disadvantages. The experiments were performed with a laboratory spray dryer and freeze-dryer using α-amylase as the model enzyme. An experimental design in star revealed that spray drying is mainly influenced by the inlet air temperature and feed flow rate, which were considered to be the main factors influencing the enzymatic activity and water activity; the long period of material exposure to high temperatures causes a partial activity loss. In the experiments of freeze drying, three methods of freezing were used (freezer, acetone and dry ice, and liquid nitrogen and samples subsequently freeze-dried for times ranging between 0-24 hours. The product obtained from the two techniques showed high enzymatic activity and low water activity. For the drying of heat-resistant enzymes, in which the product to be obtained does not have high added value, spray drying may be more economically viable because, in the freeze drying process, the process time can be considered as a limiting factor when choosing a technique.

  4. No Heat Spray Drying Technology

    Energy Technology Data Exchange (ETDEWEB)

    Beetz, Charles [ZoomEssence, Inc., Hebron, KY (United States)

    2016-06-15

    No Heat Spray Drying Technology. ZoomEssence has developed our Zooming™ spray drying technology that atomizes liquids to powders at ambient temperature. The process of drying a liquid into a powder form has been traditionally achieved by mixing a heated gas with an atomized (sprayed) fluid within a vessel (drying chamber) causing the solvent to evaporate. The predominant spray drying process in use today employs air heated up to 400° Fahrenheit to dry an atomized liquid into a powder. Exposing sensitive, volatile liquid ingredients to high temperature causes molecular degradation that negatively impacts solubility, stability and profile of the powder. In short, heat is detrimental to many liquid ingredients. The completed award focused on several areas in order to advance the prototype dryer to a commercial scale integrated pilot system. Prior to the award, ZoomEssence had developed a prototype ‘no-heat’ dryer that firmly established the feasibility of the Zooming™ process. The award focused on three primary areas to improve the technology: (1) improved ability to formulate emulsions for specific flavor groups and improved understanding of the relationship of emulsion properties to final dry particle properties, (2) a new production atomizer, and (3) a dryer controls system.

  5. Dry Mouth Treatment: Tips for Controlling Dry Mouth

    Science.gov (United States)

    ... Dry Mouth Mouthwash, which also offer protection against tooth decay. Avoid using over-the-counter antihistamines and decongestants ... and drinks because they increase your risk of tooth decay. Brush with a fluoride toothpaste — ask your dentist ...

  6. Experimental investigation of an indirect-mode forced convection solar dryer for drying thymus and mint

    International Nuclear Information System (INIS)

    El-Sebaii, A.A.; Shalaby, S.M.

    2013-01-01

    Graphical abstract: Photograph of the experimental set-up. - Highlights: • Thermal performance of an indirect-mode solar dryer is investigated. • Mathematical models are obtained for thin layer drying of thymus and mint. • Both thymus and mint show the constant and falling rate drying periods. - Abstract: An indirect-mode forced convection solar dryer was designed and fabricated. The thermal performance of the solar dryer under Tanta (latitude, 30° 47′ N and longitude, 31° E) prevailing weather conditions was experimentally investigated. The system consists of a double pass v-corrugated plate solar air heater connected to a drying chamber. A blower was used to force the heated air to the drying chamber. Drying experiments were performed for thymus (initial moisture content 95% on wet basis) and mint (initial moisture content 85% on wet basis) at an initial temperature of 29 °C. The final moisture contents for thymus and mint were reached after 34 and 5 h, respectively. Fourteen mathematical models of thin layer drying were tested to specify the suitable model for describing the drying behavior of the studied products. It was found that, Midilli and Kucuk model is convenient to describe the thin layer solar drying of mint. However, the Page and modified Page models were found to be the best among others for describing the drying curves of thymus

  7. Spent fuel drying system test results (second dry-run)

    International Nuclear Information System (INIS)

    Klinger, G.S.; Oliver, B.M.; Abrefah, J.; Marschman, S.C.; MacFarlan, P.J.; Ritter, G.A.

    1998-07-01

    The water-filled K-Basins in the Hanford 100 Area have been used to store N-Reactor spent nuclear fuel (SNF) since the 1970s. Because some leaks have been detected in the basins and some of the fuel is breached due to handling damage and corrosion, efforts are underway to remove the fuel elements from wet storage. An Integrated Process Strategy (IPS) has been developed to package, dry, transport, and store these metallic uranium fuel elements in an interim storage facility on the Hanford Site (WHC 1995). Information required to support the development of the drying processes, and the required safety analyses, is being obtained from characterization tests conducted on fuel elements removed from the K-Basins. A series of whole element drying tests (reported in separate documents, see Section 7.0) have been conducted by Pacific Northwest National Laboratory (PNNL) on several intact and damaged fuel elements recovered from both the K-East and K-West Basins. This report documents the results of the second dry-run test, which was conducted without a fuel element. With the concurrence of project management, the test protocol for this run, and subsequent drying test runs, was modified. These modifications were made to allow for improved data correlation with drying procedures proposed under the IPS. Details of these modifications are discussed in Section 3.0

  8. Potential of bio-drying applied to exhausted grape marc

    Directory of Open Access Journals (Sweden)

    Elena Cristina Rada

    2012-07-01

    Full Text Available In the present work, experimentation was carried out to study the behavior of exhausted grape marc during the bio-drying process. This process was chosen as an alternative to the typical grape marc thermal drying approach. The aim was to reduce the moisture level thanks to the biological exothermal reactions, and to increase the energy content in the biodried grape marc. The target was the generation of a product interesting for energy options. For the development of the research, a biological pilot reactor and a respirometric apparatus were used. Results demonstrated that bio-drying can decrease the water content saving the original energy content. The final material could be assumed like a solid recovered fuel, class 5:1:1 with a very low potential rate of microbial self-heating.

  9. Microencapsulation of Lactobacillus casei by spray drying.

    Science.gov (United States)

    Dos Santos, Rebeka Cristiane Silva; Finkler, Leandro; Finkler, Christine Lamenha Luna

    2014-01-01

    This study evaluates the use of spray drying to produce microparticles of Lactobacillus casei. Microorganism was cultivated in shaken flasks and the microencapsulation process was performed using a laboratory-scale spray dryer. A rotational central composite design was employed to optimise the drying conditions. High cell viability (1.1 × 10(10) CFU/g) was achieved using an inlet air temperature of 70 °C and 25% (w/v) of maltodextrin. Microparticles presented values of solubility, wettability, water activity, hygroscopicity and humidity corresponding to 97.03 ± 0.04%, 100% (in 1.16 min), 0.14 ± 0.0, 35.20 g H2O/100 g and 4.80 ± 0.43%, respectively. The microparticles were spherical with a smooth surface and thermally stable. Encapsulation improved the survival of L. casei during storage. After 60 days, the samples stored at -8 °C showed viable cell concentrations of 1.0 × 10(9) CFU/g.

  10. Modelling of thermal degradation kinetics of ascorbic acid in ...

    African Journals Online (AJOL)

    Ascorbic acid (vitamin C) loss in thermally treated pawpaw and potato was modelled mathematically. Isothermal experiments in the temperature range of 50 -80 oC for the drying of pawpaw and 60 -100 oC for the blanch-drying of potato were utilized to determine the kinetics of ascorbic acid loss in both fruit and vegetable.

  11. Modelling of Thermal Degradation Kinetics of Ascorbic Acid in ...

    African Journals Online (AJOL)

    Ascorbic acid (vitamin C) loss in thermally treated pawpaw and potato was modelled mathematically. Isothermal experiments in the temperature range of 50 -80 oC for the drying of pawpaw and 60 -100 oC for the blanch-drying of potato were utilized to determine the kinetics of ascorbic acid loss in both fruit and vegetable.

  12. Gene Expression, Bacteria Viability and Survivability Following Spray Drying of Mycobacterium smegmatis

    Directory of Open Access Journals (Sweden)

    Elizabeth Hunter Lauten

    2010-04-01

    Full Text Available We find that Mycobacterium smegmatis survives spray drying and retains cell viability in accelerated temperature stress (40 °C conditions with a success rate that increases with increasing thermal, osmotic, and nutrient-restriction stresses applied to the mycobacterium prior to spray drying. M.smegmatis that are spray dried during log growth phase, where they suffer little or no nutrient-reduction stress, survive for less than 7 days in the dry powder state at accelerated temperature stress conditions, whereas M. smegmatis that are spray dried during stationary phase, where cells do suffer nutrient reduction, survive for up to 14 days. M. smegmatis that are spray dried from stationary phase, subjected to accelerated temperature stress conditions, regrown to stationary phase, spray dried again, and resubmitted to this same process four consecutive times, display, on the fourth spray drying iteration, an approximate ten-fold increase in stability during accelerated temperature stress testing, surviving up to 105 days. Microarray tests revealed significant differences in genetic expression of M. smegmatis between log phase and stationary phase conditions, between naïve (non spray-dried and multiply cycled dried M. smegmatis (in log and stationary phase, and between M. smegmatis in the dry powder state following a single spray drying operation and after four consecutive spray drying operations. These differences, and other phenotypical differences, point to the carotenoid biosynthetic pathway as a probable pathway contributing to bacteria survival in the spray-dried state and suggests strategies for spray drying that may lead to significantly greater room-temperature stability of mycobacteria, including mycobacterium bovis bacille Calmette-Guerin (BCG, the current TB vaccine.

  13. Dry skin - self-care

    Science.gov (United States)

    ... pat skin dry then apply your moisturizer. Avoid skin care products and soaps that contain alcohol, fragrances, dyes, or other chemicals. Take short, warm baths or showers. Limit your ... gentle skin cleansers or soap with added moisturizers. Only use ...

  14. Sustaining dry surfaces under water

    DEFF Research Database (Denmark)

    Jones, Paul R.; Hao, Xiuqing; Cruz-Chu, Eduardo R.

    2015-01-01

    not been investigated, and are critically important to maintain surfaces dry under water.In this work, we identify the critical roughness scale, below which it is possible to sustain the vapor phase of water and/or trapped gases in roughness valleys – thus keeping the immersed surface dry. Theoretical......Rough surfaces immersed under water remain practically dry if the liquid-solid contact is on roughness peaks, while the roughness valleys are filled with gas. Mechanisms that prevent water from invading the valleys are well studied. However, to remain practically dry under water, additional...... mechanisms need consideration. This is because trapped gas (e.g. air) in the roughness valleys can dissolve into the water pool, leading to invasion. Additionally, water vapor can also occupy the roughness valleys of immersed surfaces. If water vapor condenses, that too leads to invasion. These effects have...

  15. Emulsion type dry cleaning system

    International Nuclear Information System (INIS)

    Kohanawa, Osamu; Matsumoto, Hiroyo.

    1988-01-01

    Protective clothing against radioactive contamination used in the radiation controlled areas of nuclear plants has been washed by the same wet washing as used for underwear washing, but recently dry cleaning is getting used in place of wet washing, which generates a large quantity of laundry drain. However, it was required to use wet washing once every five to ten dry cleanings for washing protective clothing, because conventional dry cleaning is less effective in removing water-soluble soils. Therefore, in order to eliminate wet washing, and to decrease the quantity of laundry drains, the emulsion type dry cleaning system capable of removing both oil-soluble and water-soluble soils at a time has been developed. The results of developmental experiments and actual application are presented in this paper. (author)

  16. Correlations of Mean Process Parameters for Agricultural Products Drying in Thin Bed in Solar Direct Dryers

    Directory of Open Access Journals (Sweden)

    MSc. Ciro César Bergues-Ricardo

    2015-11-01

    Full Text Available A group of correlations is given between mean parameters of drying process drying velocity, energy losses, useful energy, and thermal efficiency. Those are suitable for conditions of thin bed drying, in direct solar dryers, and may help for developing of an integral approach of solar drying in those conditions. Correlations are reliable for drying processes of diverse crop products specified, suchas roots, seeds, vegetables, fruits, wood, etc, with natural or forced convection. Correlations were validated in Cuba for usual ranges of efficiency and products in solar dryers of cover, cabinet and house types, in tropical conditions. These correlations are useful for design and exploitation ofdryers and for theoretical and practical comprehension of solar drying like a system.

  17. Photovoltaic assisted solar drying system

    International Nuclear Information System (INIS)

    Ruslan, M.H.; Othman, M.Y.; Baharuddin Yatim; Kamaruzzaman Sopian; Ali, M.I.; Ibarahim, Z.

    2006-01-01

    A photovoltaic assisted solar drying system has been constructed at the Solar Energy Research Park, Universiti Kebangsaan Malaysia. This drying system uses a custom designed parallel flow V-groove type collector. A fan powered by photovoltaic source assists the air flow through the drying system. A funnel with increasing diameter towards the top with ventilator turbine is incorporated into the system to facilitate the air flow during the absence of photovoltaic energy source. This drying system is designed with high efficiency and portability in mind so that it can readily be used at plantation sites where the crops are harvested or produced. A daily mean efficiency about 44% with mean air flow rate 0.16 kgs -1 has been achieved at mean daily radiation intensity of 800 Wm -2 . daily mean temperature of air drying chamber under the above conditions is 46 o C. Study has shown that the air flow and air temperature increase with the increase of solar radiation intensity. On a bright sunny day with instantaneous solar intensity about 600 Wm -2 , the temperature of air entering the drying chamber of 45 o C has been measured. In the absence of photovoltaic or in natural convection flow, the instantaneous efficiency decreased when solar radiation increased. The instantaneous efficiency recorded are 35% and 27% respectively at 570 Wm -2 and 745 Wm -2 of solar radiation. The temperature of drying chamber for the same amount of solar radiation are 42 o C and 48 o C respectively. Thus, the solar dryer shows a great potential for application in drying process of agricultural produce

  18. Dry and coating of powders

    International Nuclear Information System (INIS)

    Alonso, M.; Alguacil, F. J.

    1999-01-01

    This paper presents a review on the mixing and coating of powders by dry processes. The reviews surveys fundamental works on mixture characterization (mixing index definitions and sampling techniques), mixing mechanisms and models, segregation with especial emphasis on free-surface segregation, mixing of cohesive powders and interparticle forces, ordered mixing (dry coating) including mechanism, model and applications and mixing equipment selection. (Author) 180 refs

  19. Dry aging of beef; Review

    OpenAIRE

    Dashdorj, Dashmaa; Tripathi, Vinay Kumar; Cho, Soohyun; Kim, Younghoon; Hwang, Inho

    2016-01-01

    Abstract The present review has mainly focused on the specific parameters including aging (aging days, temperature, relative humidity, and air flow), eating quality (flavor, tenderness and juiciness), microbiological quality and economic (shrinkage, retail yields and cost) involved beef dry aging process. Dry aging is the process where beef carcasses or primal cuts are hanged and aged for 28 to 55 d under controlling environment conditions in a refrigerated room with 0° to 4 °C and with relat...

  20. Dry adhesives with sensing features

    International Nuclear Information System (INIS)

    Krahn, J; Menon, C

    2013-01-01

    Geckos are capable of detecting detachment of their feet. Inspired by this basic observation, a novel functional dry adhesive is proposed, which can be used to measure the instantaneous forces and torques acting on an adhesive pad. Such a novel sensing dry adhesive could potentially be used by climbing robots to quickly realize and respond appropriately to catastrophic detachment conditions. The proposed torque and force sensing dry adhesive was fabricated by mixing Carbon Black (CB) and Polydimethylsiloxane (PDMS) to form a functionalized adhesive with mushroom caps. The addition of CB to PDMS resulted in conductive PDMS which, when under compression, tension or torque, resulted in a change in the resistance across the adhesive patch terminals. The proposed design of the functionalized dry adhesive enables distinguishing an applied torque from a compressive force in a single adhesive pad. A model based on beam theory was used to predict the change in resistance across the terminals as either a torque or compressive force was applied to the adhesive patch. Under a compressive force, the sensing dry adhesive was capable of measuring compression stresses from 0.11 Pa to 20.9 kPa. The torque measured by the adhesive patch ranged from 2.6 to 10 mN m, at which point the dry adhesives became detached. The adhesive strength was 1.75 kPa under an applied preload of 1.65 kPa for an adhesive patch with an adhesive contact area of 7.07 cm 2 . (paper)

  1. Dry adhesives with sensing features

    Science.gov (United States)

    Krahn, J.; Menon, C.

    2013-08-01

    Geckos are capable of detecting detachment of their feet. Inspired by this basic observation, a novel functional dry adhesive is proposed, which can be used to measure the instantaneous forces and torques acting on an adhesive pad. Such a novel sensing dry adhesive could potentially be used by climbing robots to quickly realize and respond appropriately to catastrophic detachment conditions. The proposed torque and force sensing dry adhesive was fabricated by mixing Carbon Black (CB) and Polydimethylsiloxane (PDMS) to form a functionalized adhesive with mushroom caps. The addition of CB to PDMS resulted in conductive PDMS which, when under compression, tension or torque, resulted in a change in the resistance across the adhesive patch terminals. The proposed design of the functionalized dry adhesive enables distinguishing an applied torque from a compressive force in a single adhesive pad. A model based on beam theory was used to predict the change in resistance across the terminals as either a torque or compressive force was applied to the adhesive patch. Under a compressive force, the sensing dry adhesive was capable of measuring compression stresses from 0.11 Pa to 20.9 kPa. The torque measured by the adhesive patch ranged from 2.6 to 10 mN m, at which point the dry adhesives became detached. The adhesive strength was 1.75 kPa under an applied preload of 1.65 kPa for an adhesive patch with an adhesive contact area of 7.07 cm2.

  2. Morphology of drying blood pools

    Science.gov (United States)

    Laan, Nick; Smith, Fiona; Nicloux, Celine; Brutin, David; D-Blood project Collaboration

    2016-11-01

    Often blood pools are found on crime scenes providing information concerning the events and sequence of events that took place on the scene. However, there is a lack of knowledge concerning the drying dynamics of blood pools. This study focuses on the drying process of blood pools to determine what relevant information can be obtained for the forensic application. We recorded the drying process of blood pools with a camera and measured the weight. We found that the drying process can be separated into five different: coagulation, gelation, rim desiccation, centre desiccation, and final desiccation. Moreover, we found that the weight of the blood pool diminishes similarly and in a reproducible way for blood pools created in various conditions. In addition, we verify that the size of the blood pools is directly related to its volume and the wettability of the surface. Our study clearly shows that blood pools dry in a reproducible fashion. This preliminary work highlights the difficult task that represents blood pool analysis in forensic investigations, and how internal and external parameters influence its dynamics. We conclude that understanding the drying process dynamics would be advancement in timeline reconstitution of events. ANR funded project: D-Blood Project.

  3. Investigation of pre-drying lignite in an existing Greek power plant

    Directory of Open Access Journals (Sweden)

    Agraniotis Michalis

    2012-01-01

    Full Text Available The application of lignite pre-drying technologies in next generation of lignite power plants by utilizing low pressure steam as a drying medium instead of hot recirculated flue gas - combined with thermal utilization of the vaporized coal moisture - is expected to bring efficiency increase of 2-4 percentage points in future lignite power plants compared with today’s state of the art. The pre-drying concept is of particular importance in Greek boilers firing lignite with a high water and ash content. The combustion of Greek predried lignite has been investigated experimentally and via numerical simulations in our previous research. This study focuses on the potential integration of a lignite pre-drying system in an existing Greek power plant with dry lignite co-firing thermal share of up to 30%. The radiative and convective heat fluxes to the boiler and the overall boiler heat balance is calculated for reference and dry lignite co-firing conditions by an in-house calculation code. The overall plant’s thermal cycle is then simulated using commercial thermal cycle calculation software. The net plant efficiency is in this way determined for reference and dry coal co-firing conditions. According to the simulation results the integration of a pre-drying system and the implementation of dry lignite co-firing may bring an efficiency increase of about 1.5 percentage points in existing Greek boilers. It is therefore considered as an important measure towards improving plant efficiency and reducing specific CO2 emissions in existing plants.

  4. Freeze-drying process design by manometric temperature measurement: design of a smart freeze-dryer.

    Science.gov (United States)

    Tang, Xiaolin Charlie; Nail, Steven L; Pikal, Michael J

    2005-04-01

    To develop a procedure based on manometric temperature measurement (MTM) and an expert system for good practices in freeze drying that will allow development of an optimized freeze-drying process during a single laboratory freeze-drying experiment. Freeze drying was performed with a FTS Dura-Stop/Dura-Top freeze dryer with the manometric temperature measurement software installed. Five percent solutions of glycine, sucrose, or mannitol with 2 ml to 4 ml fill in 5 ml vials were used, with all vials loaded on one shelf. Details of freezing, optimization of chamber pressure, target product temperature, and some aspects of secondary drying are determined by the expert system algorithms. MTM measurements were used to select the optimum shelf temperature, to determine drying end points, and to evaluate residual moisture content in real-time. MTM measurements were made at 1 hour or half-hour intervals during primary drying and secondary drying, with a data collection frequency of 4 points per second. The improved MTM equations were fit to pressure-time data generated by the MTM procedure using Microcal Origin software to obtain product temperature and dry layer resistance. Using heat and mass transfer theory, the MTM results were used to evaluate mass and heat transfer rates and to estimate the shelf temperature required to maintain the target product temperature. MTM product dry layer resistance is accurate until about two-thirds of total primary drying time is over, and the MTM product temperature is normally accurate almost to the end of primary drying provided that effective thermal shielding is used in the freeze-drying process. The primary drying times can be accurately estimated from mass transfer rates calculated very early in the run, and we find the target product temperature can be achieved and maintained with only a few adjustments of shelf temperature. The freeze-dryer overload conditions can be estimated by calculation of heat/mass flow at the target product

  5. Microwave-Assisted Drying for the Conservation of Honeybee Pollen

    Directory of Open Access Journals (Sweden)

    Angelo Canale

    2016-05-01

    Full Text Available Bee pollen is becoming an important product thanks to its nutritional properties, including a high content of bioactive compounds such as essential amino acids, antioxidants, and vitamins. Fresh bee pollen has a high water content (15%–30% wt %, thus it is a good substrate for microorganisms. Traditional conservation methods include drying in a hot air chamber and/or freezing. These techniques may significantly affect the pollen organoleptic properties and its content of bioactive compounds. Here, a new conservation method, microwave drying, is introduced and investigated. The method implies irradiating the fresh pollen with microwaves under vacuum, in order to reduce the water content without reaching temperatures capable of thermally deteriorating important bioactive compounds. The method was evaluated by taking into account the nutritional properties after the treatment. The analyzed parameters were phenols, flavonoids, with special reference to rutin content, and amino acids. Results showed that microwave drying offers important advantages for the conservation of bee pollen. Irrespective of microwave power and treatment time, phenol and flavonoid content did not vary over untreated fresh pollen. Similarly, rutin content was unaffected by the microwave drying, suggesting that the microwave-assisted drying could be a powerful technology to preserve bioprotective compounds in fresh pollen.

  6. The Effect of Fermentation and Drying on Clicanthus Nutans Lindai Extract Chemical Constituents and Bioactivity

    Science.gov (United States)

    Lee, Y. Y.; Teh, P. S.; Kumaresan, S.; Tiong, C. H.

    2017-06-01

    In this study, two processes (fermentation and drying) were conducted on Clicanthus Nutans Lindau, which is well-known for its antioxidant activities. The aim of this research is to investigate the effects of these processes towards the Total Phenolic Content (TPC), antioxidant activity and the crude yield of the leaves. For the fermentation process, the fermentation time is varied for 6, 12, 24, 48 and 72 hours. For drying, oven drying (40, 45 and 50°C, freeze-drying and shade drying are investigated. Blanching was also conducted for oven dried samples (90°C for 1 minute). It was found that 12 hours fermentation produced the highest yield corresponding to Total Phenolic Content at 0.33 while 6 hours fermentation produced the highest Antioxidant Activity and yield at 2.218 x 10-10 mg/mL and 0.64 . On the other hand, 48 hours fermentation produced the highest overall extract yield at 0.64 . Analysis for antioxidant activity was carried out using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and Folin-Ciocalteau method for Total Phenolic Content. Thermal inactivation kinetics (blanching) has been investigated for oven drying samples. Results showed that 40°C oven drying and 50°C oven drying with blanching has better retention of bioactive constituents. Blanching has no significant effect on phenolic content but has increased the crude extract for higher temperature oven drying. It has no positive effect on antioxidant activity. Drying is also a better processing method compared to fermentation as drying has slightly favorable results in all three aspects. Through comparison with extraction time of 60 minutes for 40°C oven drying and 6 hour fermented samples, yield of total phenolic content and overall yield of oven dried sample is higher than fermented sample by 4.14 and 0.39 respectively as well as showing better antioxidant activity.

  7. Experimental determination of viability loss of Penicillium bilaiae conidia during convective air-drying.

    Science.gov (United States)

    Friesen, Timothy; Hill, Gordon; Pugsley, Todd; Holloway, Greg; Zimmerman, Deanna

    2005-08-01

    A study was conducted on the drying of Penicillium bilaiae, a fungal micro-organism used to promote soil-bound phosphorous uptake in several crop species, such as wheat, canola and pulse crops. A wet pellet formed from a mixture of the inoculant and a starch-based carrier was air-dried to the appropriate water activity to extend the shelf-life of the viable fungal conidia. Convective air-drying was examined as a low-energy alternative to the more expensive freeze-drying technology that is currently in use. Experiments were conducted to measure the loss of conidia viability during drying in a fixed-bed, thin-layer convective dryer. The dryer air inlet temperature and relative humidity were controlled in experiments to determine the effect of thermal and dessicative stresses on conidial viability. The measured survivor fraction was determined to be dependent on solids temperature, moisture content and drying rate. Thermal stresses became significant for process temperatures above 30 degrees C, while the survivor fraction fell sharply below a dry basis moisture ratio of 30%. Slower drying kinetics associated with high inlet air relative humidity were found to significantly improve the recovery of viable conidia. By minimising environmental stresses, survivor fractions of up to 75% could be achieved, but this result fell dramatically with the introduction of more severe conditions. A general linear statistical model is used to quantify experimental error and the significance level of each factor.

  8. Grapes (Vitis vinifera) drying by semitransparent photovoltaic module (SPVM) integrated solar dryer: an experimental study

    Science.gov (United States)

    Tiwari, Sumit; Tiwari, G. N.

    2017-12-01

    In present research paper, semi-transparent photovoltaic module (SPVM) integrated greenhouse solar drying system has been used for grapes (Vitis vinifera) drying. Based on hourly experimental information namely solar intensity, moisture evaporated, ambient air temperature, grape surface temperatures, relative humidity and greenhouse air temperature etc. heat and mass transfer coefficient for the SPVM drying system have been evaluated. It has been seen that the convective heat transfer coefficients for grapes found between 3.1-0.84 W/m2 K. Also, there is a fair agreement between theoretical and practical mass transfer (moisture evaporated) during drying of grapes with a correlation coefficient (r) and root mean square percentage deviation (e) of 0.88 and 11.56 respectively. Further, nonlinear regression procedure has been used to fit various drying models namely Henderson and Pabis model, Newton's model, and Page's model. From the analysis, it was found that Page's model is best fitted for grapes drying in SPV greenhouse as well as open sun drying. Further, net electrical energy, thermal energy and equivalent thermal energy were found to be 3.61, 17.66 and 27.15 kWh during six days of drying respectively.

  9. Effects of Different Drying Methods on the Antioxidant Activities of Leaves and Berries of Cayratia trifolia

    International Nuclear Information System (INIS)

    Rabeta, M.S.; Lin, S.P.

    2015-01-01

    This study aimed to assess the effects of fresh, thermal drying method (vacuum oven drying), and nonthermal drying method (freeze drying) on the antioxidant activities of leaves and berries of Cayratia trifolia using ferric reducing antioxidant power (FRAP) and 1,1-diphenyl-1-picrylhydrazyl radical scavenging capacity (DPPH) assays. The total phenolic content (TPC) and flavonoid content (TFC) of the leaves and berries of C. trifolia were also measured. Based on the results obtained, the TPC, TFC, and antioxidant activities of the leaves and berries were arranged in the following order: freeze-dried sample with methanol extraction > vacuum-dried sample with methanol extraction > freeze-dried sample with water extraction > vacuum-dried sample with water extraction > fresh sample with methanol extraction > fresh sample with water extraction. The results showed a significant difference (p<0.05) between the fresh and dried samples. In conclusion, freeze drying was found to be a good method for maintaining TPC, TFC, and antioxidant activities by FRAP and DPPH methods in the leaves and berries of C. trifolia. (author)

  10. Drying kinetics of whole and sliced turmeric rhizomes (Curcuma longa L. in a solar conduction dryer

    Directory of Open Access Journals (Sweden)

    A. Borah

    2015-09-01

    Full Text Available Drying of turmeric was carried out in a solar conduction dryer (SCD. Drying air temperature was achieved around 39–51 °C for an ambient temperature in the range of 25–28 °C. Moisture content from 78.65% (wb, was reduced to 6.36% (wb and 5.50% (wb for solid and sliced samples respectively in 12 h effective drying time. Drying curve of sliced samples showed more uniform falling in comparison to that of whole samples. The average effective moisture diffusivity was found to be 1.852 × 10−10 m2 s−1 for slab samples and 1.456 × 10−10 m2 s−1 for solid samples. Out of four models tried for simulation, Page model was found as best fitted thin layer drying model when simulation was done for all the drying data. The overall thermal efficiency of the dryer was found to be 55%. Drying of sliced rhizomes showed better drying kinetics and effective drying time could be reduced by slicing instead of drying in whole form.

  11. Thermal comfort

    DEFF Research Database (Denmark)

    d’Ambrosio Alfano, Francesca Romana; Olesen, Bjarne W.; Palella, Boris Igor

    2014-01-01

    Thermal comfort is one of the most important aspects of the indoor environmental quality due to its effects on well-being, people's performance and building energy requirements. Its attainment is not an easy task requiring advanced design and operation of building and HVAC systems, taking...... and operators to navigate the complex and varied world of standards in the field of thermal environment for improving indoor environmental quality and energy saving. The examples discussed in the paper will also be useful for the standardization, leading to harmonized documents more readable for all users....... into account all parameters involved. Even though thermal comfort fundamentals are consolidated topics for more than forty years, often designers seem to ignore or apply them in a wrong way. Design input values from standards are often considered as universal values rather than recommended values to be used...

  12. Parametric optimization of daylight and thermal performance ...

    African Journals Online (AJOL)

    The results of the paper show that there are meaningful optimum parameters which may help for better thermal performance through louvers in hot and dry climate of Tehran. The results indicate impressive efficiency in building industry in contemporary architecture of developing countries especially in Iran and west of Asia.

  13. Thermal conductivity of some common forest fuels

    Science.gov (United States)

    G.M. Byram; W.L. Fons

    1952-01-01

    This study was designed to obtain thermal conductivity of som common forest fuels which hitherto had defied such efforts because of their shape, size, or structure. Dry leaves and decayed. wood (punk) were modified so that conductivity measurements could be made by a thin plate uni-directional heat flow calibration stand, Resultss of these measurements are compatible...

  14. Potential evapotranspiration and continental drying

    Science.gov (United States)

    Milly, Paul C.D.; Dunne, Krista A.

    2016-01-01

    By various measures (drought area and intensity, climatic aridity index, and climatic water deficits), some observational analyses have suggested that much of the Earth’s land has been drying during recent decades, but such drying seems inconsistent with observations of dryland greening and decreasing pan evaporation. ‘Offline’ analyses of climate-model outputs from anthropogenic climate change (ACC) experiments portend continuation of putative drying through the twenty-first century, despite an expected increase in global land precipitation. A ubiquitous increase in estimates of potential evapotranspiration (PET), driven by atmospheric warming, underlies the drying trends, but may be a methodological artefact. Here we show that the PET estimator commonly used (the Penman–Monteith PET for either an open-water surface or a reference crop) severely overpredicts the changes in non-water-stressed evapotranspiration computed in the climate models themselves in ACC experiments. This overprediction is partially due to neglect of stomatal conductance reductions commonly induced by increasing atmospheric CO2 concentrations in climate models. Our findings imply that historical and future tendencies towards continental drying, as characterized by offline-computed runoff, as well as other PET-dependent metrics, may be considerably weaker and less extensive than previously thought.

  15. Thermal transitions of the amorphous polymers in wheat straw

    Science.gov (United States)

    Wolfgang Stelte; Craig Clemons; Jens K. Holm; Jesper Ahrenfeldt; Ulrik B. Henriksen; Anand R. Sanadi

    2011-01-01

    The thermal transitions of the amorphous polymers in wheat straw were investigated using dynamic mechanical thermal analysis (DMTA). The study included both natural and solvent extracted wheat straw, in moist (8–9% water content) and dry conditions, and was compared to spruce samples. Under these conditions two transitions arising from the glass transition of lignin...

  16. Effects of source, water conditioning and thermal treatment on ...

    African Journals Online (AJOL)

    Effects of source, water conditioning and thermal treatment on germination of Ricinodendron heudelotii (baill.) seeds. ... Journal of Applied Science and Technology ... R. heudelotii seeds soaked in water for 15 days at moisture content of 24 % over dry weight followed by thermal treatment improved germination by 22 %.

  17. Matrix thermalization

    Energy Technology Data Exchange (ETDEWEB)

    Craps, Ben [Theoretische Natuurkunde, Vrije Universiteit Brussel (VUB), and International Solvay Institutes, Pleinlaan 2, B-1050 Brussels (Belgium); Evnin, Oleg [Department of Physics, Faculty of Science, Chulalongkorn University, Thanon Phayathai, Pathumwan, Bangkok 10330 (Thailand); Theoretische Natuurkunde, Vrije Universiteit Brussel (VUB), and International Solvay Institutes, Pleinlaan 2, B-1050 Brussels (Belgium); Nguyen, Kévin [Theoretische Natuurkunde, Vrije Universiteit Brussel (VUB), and International Solvay Institutes, Pleinlaan 2, B-1050 Brussels (Belgium)

    2017-02-08

    Matrix quantum mechanics offers an attractive environment for discussing gravitational holography, in which both sides of the holographic duality are well-defined. Similarly to higher-dimensional implementations of holography, collapsing shell solutions in the gravitational bulk correspond in this setting to thermalization processes in the dual quantum mechanical theory. We construct an explicit, fully nonlinear supergravity solution describing a generic collapsing dilaton shell, specify the holographic renormalization prescriptions necessary for computing the relevant boundary observables, and apply them to evaluating thermalizing two-point correlation functions in the dual matrix theory.

  18. Technical aspects of the production of dried extract of Maytenus ilicifolia leaves by jet spouted bed drying.

    Science.gov (United States)

    Cordeiro, Daniel S; Oliveira, Wanderley P

    2005-08-11

    This work presents an evaluation of the performance of jet spouted bed with inert particles for production of dried extracts of Maytenus ilicifolia leaves. The development of the extraction procedure was carried-out with the aid of three factors and three levels Box-Behnken design. The effects of the extraction variables, temperature (Text); stirring time (theta); and the ratio of the plant to solvent mass (m(p)/m(s)) on the extraction yield were investigated. The drying performance and product properties were evaluated through the measurement of the product size distribution, loss on drying (Up), flavonoid degradation (D) and, process thermal efficiency (eta). These parameters were measured as a function of the inlet temperature of the spouting gas (Tgi), the feed mass flow rate of the concentrated extract relative to mass flow rate of the spouting gas (Ws/Wg), the ratio between the feed flow rate of spouting gas relative to feed flow rate at a minimum spouting condition (Q/Qms) and the static bed height (H0). A powder product with a low degradation of active substances and good physical properties were obtained for selected operating conditions. These results indicate the feasibility of this drying equipment for the production of dried extracts of M. ilicifolia Martius ex Reiss leaves.

  19. Functional Properties of Glutinous Rice Flour by Dry-Heat Treatment

    OpenAIRE

    Qin, Yang; Liu, Chengzhen; Jiang, Suisui; Cao, Jinmiao; Xiong, Liu; Sun, Qingjie

    2016-01-01

    Glutinous rice flour (GRF) and glutinous rice starch (GRS) were modified by dry-heat treatment and their rheological, thermal properties and freeze-thaw stability were evaluated. Compared with the native GRF and GRS, the water-holding ability of modified GRF and GRS were enhanced. Both the onset and peak temperatures of the modified samples increased while the endothermic enthalpy change decreased significantly (p < 0.05). Meanwhile, dry heating remarkably increased the apparent viscosities o...

  20. Economics of dry storage systems

    International Nuclear Information System (INIS)

    Moore, G.R.; Winders, R.C.

    1980-01-01

    This paper postulates a dry storage application suitable as a regional away-from-reactor storage (AFR), develops an economical system design concept and estimates system costs. The system discussed uses the experience gained in the dry storage research activities and attempts to present a best foot forward system concept. The major element of the system is the Receiving and Packaging Building. In this building fuel assemblies are removed from transportation casks and encapsulated for storage. This facility could be equally applicable to silo, vault, or caisson storage. However the caisson storage concept has been chosen for discussion purposes