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Sample records for fresh-cut cantaloupe muskmelon

  1. Microbial safety and overall quality of cantaloupe fresh-cut pieces prepared from whole cantaloupe after wet steam treatment

    Science.gov (United States)

    Fresh-cut cantaloupes have been associated with outbreaks of Salmonelosis disease and the minimally processed fresh-cut fruits have a limited shelf life because of deterioration caused by spoilage microflora and physiological processes. In this study, we evaluated the effect of minimal wet steam t...

  2. 1-Methylcyclopropene effects on temporal changes of aroma volatiles and phytochemicals of fresh-cut cantaloupe

    Science.gov (United States)

    Orange fleshed cantaloupe melons have intense aroma and flavor, but are very perishable. Changes in quality traits were characterized during storage-life of fresh-cut cantaloupe (Cucumis melo var. cantalupensis "Fiesta") cubes treated with 1.0 µL L-1 4 of 1-methylcyclopene for 24 h at 5 ºC, packaged...

  3. Growth kinetics of Listeria monocytogenes and spoilage microorganisms in fresh-cut cantaloupe.

    Science.gov (United States)

    Fang, Ting; Liu, Yanhong; Huang, Lihan

    2013-05-01

    The main objective of this study was to investigate the growth kinetics of Listeria monocytogenes and background microorganisms in fresh-cut cantaloupe. Fresh-cut cantaloupe samples, inoculated with three main serotypes (1/2a, 1/2b, and 4b) of L. monocytogenes, were incubated at different temperatures, ranging from 4 to 43 °C, to develop kinetic growth models. During storage studies, the population of both background microorganisms and L. monocytogenes began to increase almost immediately, with little or no lag phase for most growth curves. All growth curves, except for two growth curves of L. monocytogenes 1/2a at 4 °C, developed to full curves (containing exponential and stationary phases), and can be described by a 3-parameter logistic model. There was no significant difference (P = 0.28) in the growth behaviors and the specific growth rates of three different serotypes of L. monocytogenes inoculated to fresh-cut cantaloupe. The effect of temperature on the growth of L. monocytogenes and spoilage microorganisms was evaluated using three secondary models. For L. monocytogenes, the minimum and maximum growth temperatures were estimated by both the Ratkowsky square-root and Cardinal parameter models, and the optimum temperature and the optimum specific growth rate by the Cardinal parameter model. An Arrhenius-type model provided more accurate estimation of the specific growth rate of L. monocytogenes at temperatures <4 °C. The kinetic models developed in this study can be used by regulatory agencies and food processors for conducting risk assessment of L. monocytogenes in fresh-cut cantaloupe, and for estimating the shelf-life of fresh-cut products.

  4. Microbial safety and overall quality of cantaloupe fresh-cut pieces prepared from whole fruit after wet steam treatment.

    Science.gov (United States)

    Ukuku, Dike O; Geveke, David J; Chau, Lee; Niemira, Brendan A

    2016-08-16

    Fresh-cut cantaloupes have been associated with outbreaks of Salmonellosis. Minimally processed fresh-cut fruits have a limited shelf life because of deterioration caused by spoilage microflora and physiological processes. The objectives of this study were to use a wet steam process to 1) reduce indigenous spoilage microflora and inoculated populations of Salmonella, Escherichia coli O157:H7 and Listeria monocytogenes on the surface of cantaloupes, and 2) reduce the populations counts in cantaloupe fresh-cut pieces after rind removal and cutting. The average inocula of Salmonella, E. coli O157:H7 and Listeria monocytogenes was 10(7)CFU/ml and the populations recovered on the cantaloupe rind surfaces after inoculation averaged 4.5, 4.8 and 4.1logCFU/cm(2), respectively. Whole cantaloupes were treated with a wet steam processing unit for 180s, and the treated melons were stored at 5°C for 29days. Bacterial populations in fresh-cut pieces prepared from treated and control samples stored at 5 and 10°C for up to 12days were determined and changes in color (CIE L*, a*, and b*) due to treatments were measured during storage. Presence and growth of aerobic mesophilic bacteria and Salmonella, E. coli O157:H7 and L. monocytogenes were determined in fresh-cut cantaloupe samples. There were no visual signs of physical damage on all treated cantaloupe surfaces immediately after treatments and during storage. All fresh-cut pieces from treated cantaloupes rind surfaces were negative for bacterial pathogens even after an enrichment process. Steam treatment significantly (psteam treatment of cantaloupes rind surfaces designated for fresh-cut preparation will enhance the microbial safety of fresh-cut pieces, by reducing total bacterial populations. This process holds the potential to significantly reduce the incidence of foodborne illness associated with fresh-cut fruits.

  5. Effect of hot water surface pasteurization of whole fruit on shelf life and quality of fresh-cut cantaloupe.

    Science.gov (United States)

    Fan, X; Annous, B A; Beaulieu, J C; Sites, J E

    2008-04-01

    Cantaloupes are associated with recent outbreaks of foodborne illnesses and recalls. Therefore, new approaches are needed for sanitization of whole and cut fruit. In the present study, whole cantaloupes were submerged into water in the following 3 conditions: 10 degrees C water for 20 min (control), 20 ppm chlorine at 10 degrees C for 20 min, and 76 degrees C water for 3 min. Populations of microflora were measured on the rinds of the whole cantaloupes. Quality and microbial populations of fresh-cut cantaloupes prepared from whole fruit were analyzed after 1, 6, 8, 10, 13, 16, and 20 d of storage at 4 degrees C. The hot water significantly reduced both total plate count (TPC) and yeast and mold count on rind of whole fruits while chlorine or cold water wash did not result in a significant reduction of microbial population. Fresh-cut pieces prepared from hot water-treated cantaloupes had lower TPC than the other 2 treatments in the later storage periods (days 13 to 20) in 2 of 3 trials. The hot water treatment of whole fruits was inconsistent in reducing yeast and mold count of fresh-cut pieces. Soluble solids content, ascorbic acid content, fluid loss, and aroma and appearance scores were not consistently affected by either hot water or chlorine treatment. Our results suggested that hot water pasteurization of whole cantaloupes frequently resulted in lower TPCs of fresh-cut fruit during storage and did not negatively affect quality of fresh-cut cantaloupes.

  6. Use of chemical sanitizers to reduce microbial populations and maintain quality of whole and fresh-cut cantaloupe.

    Science.gov (United States)

    Fan, Xuetong; Annous, Bassam A; Keskinen, Lindsey A; Mattheis, James P

    2009-12-01

    Whole cantaloupes either not inoculated or inoculated with Salmonella Poona were submerged in water, 180 ppm of chlorine, acidified calcium sulfate (ACS: 1.2% Safe(2)O-ACS50), 1,000 ppm of acidified sodium chlorite (ASC), 80 ppm of peroxyacetic acid (PAA), and a combination of ACS and PAA for 10 min. Although only ASC and the combination of ACS and PAA significantly reduced the aerobic plate count of samples taken from the surface of whole cantaloupe (compared with samples taken from cantaloupe submerged in water only), all treatments reduced yeast and mold counts on the whole cantaloupe. However, none of the treatments of whole cantaloupes consistently reduced yeast and mold counts for the samples of fresh-cut cantaloupes. The aerobic plate counts for fresh-cut cantaloupe were reduced by 1 to 2 log CFU/g by sanitization of whole fruit with ASC, ACS, and the combination of ACS and PAA. The low bacterial population on the fresh-cut fruit was maintained during 14 days of storage at 4 degrees C. All treatments had a limited effect on the population of Salmonella, achieving no more than a 1.5-log reduction of the pathogen inoculated on the surface of the whole cantaloupes. Salmonella was nondetectable via direct plating (with a detection limit of 0.4 log CFU/g) in fresh-cut cantaloupes prepared from whole cantaloupes treated with any of the sanitizers. However, after enrichment, Salmonella often was detectable. Color, texture, soluble solids, pH, ascorbic acid, and drip loss of cut cantaloupes were not consistently affected by any of the whole-fruit treatments. Overall, treatments of whole cantaloupe with ASC, ACS, and the combination of ACS and PAA at the concentrations tested permitted a significant reduction in Salmonella and native microflora of whole and cut fruit; however, Salmonella still could be found in cut cantaloupes from all treatments.

  7. Survival and growth of Listeria monocytogenes on fresh-cut ‘Athena’ and ‘Rocky Ford’ cantaloupes during storage at 4 and 10°C

    Science.gov (United States)

    Cantaloupes, marketed as ‘Rocky Ford’, were implicated in the fatal U.S. multi-state outbreak of listeriosis in 2011. Listeria monocytogenes can survive on whole cantaloupes and can be transferred to the flesh of melons. The growth of L. monocytogenes on fresh-cut ‘Athena’ and ‘Rocky Ford’ cantaloup...

  8. Survival and growth parameters of Escherichia Coli 0157:H7, Salmonella Spp. and Listeria Monocytogenes on fresh-cut pieces prepared from whole cantaloupe treated with Lovit sanitizer

    Science.gov (United States)

    Incidence of foodborne illness due to consumption of fresh-cut melons contaminated with human bacterial pathogens and recalls of such contaminated fresh-cut melons continues to be a food safety problem. Cantaloupe rind surfaces were inoculated with a three cocktail of E. coli O157:H7, Salmonella spp...

  9. Survival and Growth of Listeria monocytogenes on Fresh-Cut "Athena" and "Rocky Ford" Cantaloupes During Storage at 4°C and 10°C.

    Science.gov (United States)

    Nyarko, Esmond; Kniel, Kalmia E; Reynnells, Russell; East, Cheryl; Handy, Eric T; Luo, Yaguang; Millner, Patricia D; Sharma, Manan

    2016-11-01

    Cantaloupes, marketed as "Rocky Ford," were implicated in the U.S. multistate outbreak of listeriosis in 2011, which caused multiple fatalities. Listeria monocytogenes can survive on whole cantaloupes and can be transferred to the flesh of melons. The growth of L. monocytogenes on fresh-cut "Athena" and "Rocky Ford" cantaloupe cultivars during refrigerated storage was evaluated. Fresh-cut cubes (16.4 cm(3)) from field-grown cantaloupes were each inoculated with 5 log10 CFU/mL of a multi-strain mixture of L. monocytogenes and stored at 4°C or 10°C. Inoculated fresh-cut cubes were also: (1) continuously stored at 4°C for 3 days; (2) temperature-abused (TA: 25°C for 4 h) on day 0; or (3) stored at 4°C for 24 h, exposed to TA on day 1, and subsequently stored at 4°C until day 3. L. monocytogenes populations on fresh-cut melons continuously stored at 4°C or 10°C were enumerated on selected days for up to 15 days and after each TA event. Brix values for each cantaloupe variety were determined. L. monocytogenes populations on fresh-cut cantaloupe cubes stored at 4°C increased by 1.0 and 3.0 log10 CFU/cube by day 7 and 15, respectively, whereas those stored at 10°C increased by 3.0 log10 CFU/cube by day 7. Populations of L. monocytogenes on fresh-cut cantaloupes stored at 10°C were significantly (p fresh-cut "Athena" and "Rocky Ford" cubes, even though "Athena" cubes had significantly higher Brix values than the "Rocky Ford" fruit. L. monocytogenes populations on fresh-cut cantaloupes exposed to TA on day 1 and then refrigerated were significantly greater (0.74 log10 CFU) than those stored continuously at 4°C for 3 days. Storage at 10°C or exposure to TA events promoted growth of L. monocytogenes on fresh-cut cantaloupe during refrigerated storage.

  10. Effect of native microflora, waiting period, and storage temperature on Listeria monocytogenes serovars transferred from cantaloupe rind to fresh-cut pieces during preparation.

    Science.gov (United States)

    Ukuku, Dike O; Olanya, Modesto; Geveke, David J; Sommers, Christopher H

    2012-11-01

    The most recent outbreak of listeriosis linked to consumption of fresh-cut cantaloupes indicates the need to investigate the behavior of Listeria monocytogenes in the presence of native microflora of cantaloupe pieces during storage. Whole cantaloupes were inoculated with L. monocytogenes (10(8)-CFU/ml suspension) for 10 min and air dried in a biosafety cabinet for 1 h and then treated (unwashed, water washed, and 2.5% hydrogen peroxide washed). Fresh-cut pieces (∼3 cm) prepared from these melons were left at 5 and 10°C for 72 h and room temperature (20°C) for 48 h. Some fresh-cut pieces were left at 20°C for 2 and 4 h and then refrigerated at 5°C. Microbial populations of fresh-cut pieces were determined by the plate count method or enrichment method immediately after preparation. Aerobic mesophilic bacteria, yeast and mold of whole melon, and inoculated populations of L. monocytogenes on cantaloupe rind surfaces averaged 6.4, 3.3, and 4.6 log CFU/cm(2), respectively. Only H(2)O(2) (2.5%) treatment reduced the aerobic mesophilic bacteria, yeast and mold, and L. monocytogenes populations to 3.8, 0.9, and 1.8 log CFU/cm(2), respectively. The populations of L. monocytogenes transferred from melon rinds to fresh-cut pieces were below detection but were present by enrichment. Increased storage temperatures enhanced the lag phases and growth of L. monocytogenes. The results of this study confirmed the need to store fresh-cut cantaloupes at 5°C immediately after preparation to enhance the microbial safety of the fruit.

  11. Survival and growth parameters of Escherichia coli 0157:H7, Salmonella Spp. and Listeria monocytogenes on cantaloupe fresh-cut pieces during storage

    Science.gov (United States)

    For health reasons, people are consuming fresh-cut fruits with or without minimal processing, thereby, exposing themselves to the risk of foodborne illness if such fruits are contaminated with bacteria pathogens. Cantaloupe rind surfaces were inoculated with a three cocktails of Escherichia coli O15...

  12. Predictive modeling for growth of non- and cold-adapted Listeria monocytogenes on fresh-cut cantaloupe at different storage temperatures.

    Science.gov (United States)

    Hong, Yoon-Ki; Yoon, Won Byong; Huang, Lihan; Yuk, Hyun-Gyun

    2014-06-01

    The aim of this study was to determine the growth kinetics of Listeria monocytogenes, with and without cold-adaption, on fresh-cut cantaloupe under different storage temperatures. Fresh-cut samples, spot inoculated with a 4-strain cocktail of L. monocytogenes (∼3.2 log CFU/g), were exposed to constant storage temperatures held at 10, 15, 20, 25, or 30 °C. All growth curves of L. monocytogenes were fitted to the Baranyi, modified Gompertz, and Huang models. Regardless of conditions under which cells grew, the time needed to reach 5 log CFU/g decreased with the elevated storage temperature. Experimental results showed that there were no significant differences (P > 0.05) in the maximum growth rate k (log CFU/g h(-1) ) and lag phase duration λ (h) between the cultures of L. monocytogenes with or without previous cold-adaption treatments. No distinct difference was observed in the growth pattern among 3 primary models at various storage temperatures. The growth curves of secondary modeling were fitted on an Arrhenius-type model for describing the relationship between k and temperature of the L. monocytogenes on fresh-cut cantaloupe from 10 to 30 °C. The root mean square error values of secondary models for non- and cold-adapted cells were 0.018, 0.021, and 0.024, and 0.039, 0.026, and 0.017 at the modified Gompertz, Baranyi, and Huang model, respectively, indicating that these 3 models presented the good statistical fit. This study may provide valuable information to predict the growth of L. monocytogenes on fresh-cut cantaloupes at different storage conditions. Listeriosis has occurred and increased along with the increased demand of fresh and fresh-cut fruits and vegetables. This study was conducted to predict the growth of non- and cold-adapted L. monocytogenes on fresh-cut cantaloupe at different temperature using mathematical model. These results can be helpful for risk assessments of L. monocytogenes in fresh-cut cantaloupe. This study provides valuable

  13. Combination of hot-water surface pasteurization of whole fruit and low-dose gamma irradiation of fresh-cut cantaloupe.

    Science.gov (United States)

    Fan, Xuetong; Annous, Bassam A; Sokorai, Kimberly J B; Burke, Angela; Mattheis, James P

    2006-04-01

    Improvements in methods for disinfecting fresh-cut cantaloupe could reduce spoilage losses and reduce the risk of foodborne illness from human pathogen contamination. The objective of this study was to investigate the feasibility of using hot-water treatment in combination with low-dose irradiation to reduce native microbial populations while maintaining the quality of fresh-cut cantaloupe. Whole cantaloupes were washed in tap water at 20 or 76 degrees C for 3 min. Fresh-cut cantaloupe cubes, prepared from the washed fruit, were then packaged in clamshell containers, and half the samples were exposed to 0.5 kGy of gamma radiation. Native microflora populations and sensory qualities were evaluated during the subsequent 7 days of storage at 4 degrees C. The hot-water surface pasteurization reduced the microflora population by 3.3 log on the surface of whole fruits, resulting in a lower microbial load on the fresh-cut cubes compared with cubes cut from fruit treated with cold water. Irradiation of cubes prepared from untreated fruit to an absorbed dose of 0.5 kGy achieved a low microbial load similar to that of cubes prepared from hot-water-treated fruit. The combination of the two treatments was able to further reduce the microflora population. During storage, the headspace atmosphere of the packages was not significantly influenced by any of the treatments. Color, titratable acidity, pH, ascorbic acid, firmness, and drip loss were not consistently affected by treatment with irradiation, hot water, or the combination of the two. Cubes prepared from hot-water-treated whole fruit had slightly lower soluble solids content. The combination of hot-water pasteurization of whole cantaloupe and low-dose irradiation of packaged fresh-cut melon can reduce the population of native microflora while maintaining the quality of this product.

  14. Efficacy of Sanitizer Treatments on Survival and Growth Parameters of Escherichia coli O157:H7, Salmonella, and Listeria monocytogenes on Fresh-Cut Pieces of Cantaloupe during Storage.

    Science.gov (United States)

    Ukuku, Dike O; Huang, Lihan; Sommers, Christopher

    2015-07-01

    For health reasons, people are consuming fresh-cut fruits with or without minimal processing and, thereby, exposing themselves to the risk of foodborne illness if such fruits are contaminated with bacterial pathogens. This study investigated survival and growth parameters of Escherichia coli O157:H7, Salmonella, Listeria monocytogenes, and aerobic mesophilic bacteria transferred from cantaloupe rind surfaces to fresh-cut pieces during fresh-cut preparation. All human bacterial pathogens inoculated on cantaloupe rind surfaces averaged ∼4.8 log CFU/cm(2), and the populations transferred to fresh-cut pieces before washing treatments ranged from 3 to 3.5 log CFU/g for all pathogens. A nisin-based sanitizer developed in our laboratory and chlorinated water at 1,000 mg/liter were evaluated for effectiveness in minimizing transfer of bacterial populations from cantaloupe rind surface to fresh-cut pieces. Inoculated and uninoculated cantaloupes were washed for 5 min before fresh-cut preparation and storage of fresh-cut pieces at 5 and 10°C for 15 days and at 22°C for 24 h. In fresh-cut pieces from cantaloupe washed with chlorinated water, only Salmonella was found (0.9 log CFU/g), whereas E. coli O157:H7 and L. monocytogenes were positive only by enrichment. The nisin-based sanitizer prevented transfer of human bacteria from melon rind surfaces to fresh-cut pieces, and the populations in fresh-cut pieces were below detection even by enrichment. Storage temperature affected survival and the growth rate for each type of bacteria on fresh-cut cantaloupe. Specific growth rates of E. coli O157:H7, Salmonella, and L. monocytogenes in fresh-cut pieces were similar, whereas the aerobic mesophilic bacteria grew 60 to 80 % faster and had shorter lag phases.

  15. Effect of Hydrogen Peroxide in Combination with Minimal Thermal Treatment for Reducing Bacterial Populations on Cantaloupe Rind Surfaces and Transfer to Fresh-Cut Pieces.

    Science.gov (United States)

    Ukuku, Dike O; Mukhopadhyay, Sudarsan; Geveke, David; Olanya, Modesto; Niemira, Brendan

    2016-08-01

    Surface structure and biochemical characteristics of bacteria and produce play a major role in how and where bacteria attach, complicating decontamination treatments. Whole cantaloupe rind surfaces were inoculated with Salmonella, Escherichia coli O157:H7, and Listeria monocytogenes at 10(7) CFU/ml. Average population size of Salmonella, Escherichia coli O157:H7, and L. monocytogenes recovered after surface inoculation was 4.8 ± 0.12, 5.1 ± 0.14, and 3.6 ± 0.13 log CFU/cm(2), respectively. Inoculated melons were stored at 5 and 22°C for 7 days before washing treatment interventions. Intervention treatments used were (i) water (H2O) at 22°C, (ii) H2O at 80°C, (iii) 3% hydrogen peroxide (H2O2) at 22°C, and (iv) a combination of 3% H2O2 and H2O at 80°C for 300 s. The strength of pathogen attachment (SR value) at days 0, 3, and 7 of storage was determined, and then the efficacy of the intervention treatments to detach, kill, and reduce transfer of bacteria to fresh-cut pieces during fresh-cut preparation was investigated. Populations of E. coli O157:H7 attached to the rind surface at significantly higher levels (P < 0.05) than Salmonella and L. monocytogenes, but Salmonella exhibited the strongest attachment (SR value) at all days tested. Washing with 3% H2O2 alone led to significant reduction (P < 0.05) of bacteria and caused some changes in bacterial cell morphology. A combination treatment with H2O and 3% H2O2 at 8°C led to an average 4-log reduction of bacterial pathogens, and no bacterial pathogens were detected in fresh-cut pieces prepared from this combination treatment, including enriched fresh-cut samples. The results of this study indicate that the microbial safety of fresh-cut pieces from treated cantaloupes was improved at day 6 of storage at 5°C and day 3 of storage at 10°C.

  16. Use of chemical sanitizers to reduce microbial populations and maintain quality of whole and fresh-cut cantaloupe

    Science.gov (United States)

    Whole cantaloupes either not inoculated or inoculated with Salmonella Poona were submerged in water, 100 ppm chlorine, acidified calcium sulfate (ACS: 1.2% Safe2O ACS50), 1000 ppm acidified sodium chlorite (Sanova), 80 ppm peroxyacetic acid (Tsunami), and combination of ACS and Tsunami for 10 min. ...

  17. Effect of combined underwater processing and mild pre-cut heat treatment on the sensory quality and storage of fresh-cut cantaloupe melon.

    Science.gov (United States)

    Fresh cut fruit, mildly preheated and processed underwater, was shown to have superior sensory quality attributes compared to the control fresh cut fruit processed totally in open air. Less leakage of ions and enhanced plasma membrane integrity was displayed in both the fresh cut fruit processed un...

  18. Processamento mínimo do melão Cantaloupe com uso de doses de cloreto de cálcio e quelato aminocálcico Fresh-cut of Cantaloupe melon using doses of calcium chloride and calcium amino acid chelate

    Directory of Open Access Journals (Sweden)

    Francisca Ligia de C Machado

    2008-03-01

    Full Text Available A qualidade de melão Cantaloupe 'Hy-Mark' minimamente processado em cubos, tratado com cloreto de cálcio ou quelato aminocálcico e armazenado sob refrigeração foi avaliada. Os frutos foram colhidos em estádio de maturação comercial, caracterizado por camada de abscisão do pedúnculo com até 75% de desprendimento, teor de sólidos solúveis mínimo de 9.0ºBrix, coloração externa verde-escuro e firmeza da polpa máxima de 18 N, no Agropolo Mossoró-Assu (RN, e transportados para o laboratório da Embrapa Agroindústria Tropical, onde foram selecionados, sanitizados, processados e tratados a 10ºC. Posteriormente os cubos foram imersos em cálcio a 0,5% e 1,0%, na forma de cloreto de cálcio e cálcio 0,5% e 1% na forma de quelato aminocálcico por três minutos, drenados, acondicionados em embalagens PET e armazenados a 5±1ºC e 90±5% UR por 18 dias. As análises de aparência, coloração, firmeza da polpa, teores de cálcio total e livre, sólidos solúveis totais, acidez total titulável e pH foram realizadas logo após o processamento e em intervalos de três dias até o décimo oitavo dia. A aplicação de cálcio na forma de cloreto de cálcio e quelato aminocálcico reteve a firmeza da polpa e conservou a aparência das amostras por todo o período experimental, destacando-se principalmente a aplicação de 1,0% de cálcio na forma de cloreto de cálcio que não só resultou em maior retenção da firmeza, como também proporcionou os maiores teores de cálcio total.The quality of fresh-cut Cantaloupe 'Hy-Mark' melon treated with calcium chloride or calcium amino acid chelate and stored under refrigeration was studied. Fruits were harvested at commercial maturity, taking into consideration slip stage when only 25% of the stem remained intact upon removal from the vine, soluble solids no lower than 9.0ºBrix, firmness no higher than 18N, and dark green color of the rind. Fruits were transported to the postharvest laboratory

  19. Quality changes and nutrient retention in fresh-cut versus whole fruits during storage.

    Science.gov (United States)

    Gil, María I; Aguayo, Encarna; Kader, Adel A

    2006-06-14

    The influences of processing and storage on the quality indices and nutritional content of fresh-cut fruits were evaluated in comparison to whole fruits stored for the same duration but prepared on the day of sampling. Fresh-cut pineapples, mangoes, cantaloupes, watermelons, strawberries, and kiwifruits and whole fruits were stored for up to 9 days in air at 5 degrees C. The postcutting life based on visual appearance was shorter than 6 days for fresh-cut kiwifruit and shorter than 9 days for fresh-cut pineapple, cantaloupe, and strawberry. On the other hand, fresh-cut watermelon and mango pieces were still marketable after 9 days at 5 degrees C. Losses in vitamin C after 6 days at 5 degrees C were fresh-cut fruit products tested after 6 days at 5 degrees C. Light exposure promoted browning in pineapple pieces and decreased vitamin C content in kiwifruit slices. Total carotenoids contents decreased in cantaloupe cubes and kiwifruit slices, but increased in mango and watermelon cubes in response to light exposure during storage at 5 degrees C for up to 9 days. There was no effect of exposure to light on the content of phenolics. In general, fresh-cut fruits visually spoil before any significant nutrient loss occurs.

  20. Biochemical and color changes of fresh-cut melon (Cucumis melo L. cv. Galia treated with UV-C

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    Rezzan Kasim

    2014-09-01

    Full Text Available The importance of minimally processed commodities in the retail groceries of most developed countries has been rising continuously during the last decades. Cantaloupe melon is used more than any other fruit in fresh-cut processing. Ultraviolet (UV light has been extensively used to simulate biological stres in plants and for determining resistance mechanisms of plant tissues. In this study the effect of ultraviolet irradiation on some properties of fresh-cut cantalope melon was determined during storage. Freshly cut cantalope melons cubes treated with ultraviolet irradiation at the doses of 1, 2 or 3 min before storage, and then placed in a cold room at 5±1°C temperature and 85-90% RH. Hue angle values of control group is low compared to UV-C treated samples, whereas L values of is high. EL of UV treated samples higher than those of control group. Total soluble solids of fresh-cut melon samples in UC3 treatment increased during storage. The results indicate that UV-C treatments on fresh-cut cantaloupe melon cubes increased total soluble solids independently from water loss.

  1. Factors affecting quality and safety of fresh-cut produce.

    Science.gov (United States)

    Francis, G A; Gallone, A; Nychas, G J; Sofos, J N; Colelli, G; Amodio, M L; Spano, G

    2012-01-01

    The quality of fresh-cut fruit and vegetable products includes a combination of attributes, such as appearance, texture, and flavor, as well as nutritional and safety aspects that determine their value to the consumer. Nutritionally, fruit and vegetables represent a good source of vitamins, minerals, and dietary fiber, and fresh-cut produce satisfies consumer demand for freshly prepared, convenient, healthy food. However, fresh-cut produce deteriorates faster than corresponding intact produce, as a result of damage caused by minimal processing, which accelerates many physiological changes that lead to a reduction in produce quality and shelf-life. The symptoms of produce deterioration include discoloration, increased oxidative browning at cut surfaces, flaccidity as a result of loss of water, and decreased nutritional value. Damaged plant tissues also represent a better substrate for growth of microorganisms, including spoilage microorganisms and foodborne pathogens. The risk of pathogen contamination and growth is one of the main safety concerns associated with fresh-cut produce, as highlighted by the increasing number of produce-linked foodborne outbreaks in recent years. The pathogens of major concern in fresh-cut produce are Listeria monocytogenes, pathogenic Escherichia coli mainly O157:H7, and Salmonella spp. This article describes the quality of fresh-cut produce, factors affecting quality, and various techniques for evaluating quality. In addition, the microbiological safety of fresh-cut produce and factors affecting pathogen survival and growth on fresh-cut produce are discussed in detail.

  2. ANTIOXIDANT ENZYME ACTIVITY AND FRESH-CUT ARRACACHA QUALITY

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    Hêmina Carla Vilela

    2015-06-01

    Full Text Available The arracacha is an alternative of fresh-cut product; however it can be easily degraded after the processing techniques. The objective of this work was to evaluate the useful life of fresh-cut arracacha submitted to two types of cuts and storage, as well as to evaluate the activity of antioxidant enzymes. The roots were selected, sanitized and submitted to two cut types: cubed and grated. Then they were evaluated at 3 times: 0, 3 and 7 days. The cutting in cubes provided higher quality and lower SOD, CAT and APX activity. However, the grated product presented higher PG activity and lower PPO activity. The microbiological safety and the nutritional value were maintained in both cuts during the whole storage period. The useful life, regarding the physicochemical, nutritional and microbiological aspects, can be established at 7 days under refrigeration for fresh-cut arracacha.

  3. Incidence of chilling injury in fresh-cut 'Kent' mangoes

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    The preferred storage temperature for fresh-cut fruits in terms of visual quality retention is around 5 °C, which is considered to be a chilling temperature for chilling sensitive tropical fruits like mango (Mangifera indica L.). Changes in visual and compositional quality factors, aroma volatile pr...

  4. Factors affecting the postharvest performance of fresh-cut lettuce

    NARCIS (Netherlands)

    Witkowska, I.M.

    2013-01-01

    The quality of fresh-cut fruits and vegetables is often offset by a rapid deterioration, due to severe physical stress, such as peeling, cutting, slicing, shredding, and trimming. Due to this wounding, the already short shelf-life of these harvested products is even more reduced in the market place.

  5. Cultivar affects browning susceptibility of freshly cut star fruit slices

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    Teixeira Gustavo Henrique de Almeida

    2006-01-01

    Full Text Available Consumption of freshly-cut horticultural products has increased in the last few years. The principal restraint to using freshly-cut carambola is its susceptibility to tissue-browning, due to polyphenol oxidase-mediated oxidation of phenolic compounds present in the tissue. The current study investigated the susceptibility to browning of star fruit slices (Averrhoa carambola L. of seven genotypes (Hart, Golden Star, Taen-ma, Nota-10, Malásia, Arkin, and Fwang Tung. Cultivar susceptibility to browning as measured by luminosity (L* varied significantly among genotypes. Without catechol 0.05 M, little changes occurred on cut surface of any cultivars during 6 hour at 25degreesC, 67% RH. Addition of catechol led to rapid browning, which was more intense in cvs. Taen-ma, Fwang Tung, and Golden Star, with reduction in L* value of 28.60%, 27.68%, and 23.29%, respectively. Browning was more intense in the center of the slices, particularly when treated with catechol, indicating highest polyphenol oxidase (PPO concentration. Epidermal browning, even in absence of catechol, is a limitation to visual acceptability and indicates a necessity for its control during carambola processing. Care must be given to appropriate selection of cultivars for fresh-cut processing, since cultivar varied in browning susceptibility in the presence of catechol.

  6. Importance of Seed Quality for the Fresh-cut Chain

    DEFF Research Database (Denmark)

    Deleuran, Lise Christina; Olesen, Merete Halkjær; Shetty, Nisha

    2011-01-01

    Seed is the most fundamental input in vegetable production on, which the effectiveness of other inputs and outputs depends. If the seed is of poor quality, the use of other inputs is less successful and will occasionally be irrelevant. A definition of seed quality will depend upon the use for......, which the seed is intended. Viability, vigor, uniformity, purity and health of the seeds are quality parameters important for all production systems. The ideal situation for both fresh produce and fresh cut would be seeds, which germinate uniform at a high percentage and subsequently grow relatively...... fast to the desired size, thus, resulting in leaves of improved quality. It is likely that such leaves will be more able to withstand the rigorous processing that includes harvest, transportation, washing, sanitization, de-watering and packaging. This ideal situation would both be determined...

  7. Growth Potential of Listeria Monocytogenes and Staphylococcus Aureus on Fresh-Cut Tropical Fruits.

    Science.gov (United States)

    Feng, Ke; Hu, Wenzhong; Jiang, Aili; Xu, Yongping; Sarengaowa; Li, Xiaobo; Bai, Xue

    2015-11-01

    The objective of this study was to evaluate the fate of Staphylococcus aureus, Listeria monocytogenes, and natural microbiota on fresh-cut tropical fruits (pitaya, mango, papaya and pineapple) with commercial PVC film at different storage temperature (5, 13, and 25 °C). The results showed that S. aureus, L. monocytogenes, and natural microbiota increased significantly on fresh-cut tropical fruits at 25 °C. Both pathogen and natural microbiota were able to grow on fresh-cut tropical fruits at 13 °C. The maximum population of L. monocytogenes was higher than that of S. aureus on fresh-cut tropical fruits. L. monocytogenes and S. aureus could survive without growth on fresh-cut pitaya, mango, and papaya at 5 °C. The population of L. monocytogenes declined significantly on fresh-cut pineapple at all temperature, indicating composition of fresh-cut pineapple could inhibit growth of L. monocytogenes. However, S. aureus was still able to grow on fresh-cut pineapple at storage temperature. Thus, this study suggests that 4 kinds of fresh-cut tropical fruits (pitaya, mango, papaya, and pineapple) should be stored at low temperature to extend shelf life as well as to ensure the safety of fresh-cut fruits. The data collected in this study demonstrated that L. monocytogenes and S. aureus were able to grow on fresh-cut tropical fruits at different temperatures. These results could be of interest in knowing the capacity of tropical fruits to support the growth of L. monocytogenes and S. aureus. This information may also be useful to local and state regulatory officials responsible for food safety.

  8. Determination of Phytoestrogen Content in Fresh-Cut Legume Forage

    Directory of Open Access Journals (Sweden)

    Pavlína Hloucalová

    2016-07-01

    Full Text Available The aim of the study was to determine phytoestrogen content in fresh-cut legume forage. This issue has been much discussed in recent years in connection with the health and safety of feedstuffs and thus livestock health. The experiments were carried out on two experimental plots at Troubsko and Vatín, Czech Republic during June and July in 2015. Samples were collected of the four forage legume species perennial red clover (variety “Amos”, alfalfa (variety “Holyně”, and annuals Persian clover and Alexandrian clover. Forage was sampled twice at regular three to four day intervals leading up to harvest and a third time on the day of harvest. Fresh and wilted material was analyzed using liquid chromatography–mass spectrometry (LC-MS. Higher levels ( p < 0.05 of isoflavones biochanin A (3.697 mg·g −1 of dry weight and formononetin (4.315 mg·g −1 of dry weight were found in red clover than in other species. The highest isoflavone content was detected in red clover, reaching 1.001% of dry matter ( p < 0.05, representing a risk for occurrence of reproduction problems and inhibited secretion of animal estrogen. The phytoestrogen content was particularly increased in wilted forage. Significant isoflavone reduction was observed over three to four day intervals leading up to harvest.

  9. Dietitians' attitudes, perceptions, and usage patterns for fresh-cut fruit and vegetables.

    Science.gov (United States)

    Sanford, Katherine A; Johnston, Elizabeth M; Porter, Jennifer L; Lowe, Judith; Oxby, Debra M

    2008-01-01

    New fresh-cut fruit and vegetable products are being developed worldwide. Nutrition educators' perceptions of these products were studied. Professional dietitians in Nova Scotia were asked to complete a questionnaire on their use of fresh-cut produce. The questionnaire also elicited their attitudes and perceptions about the convenience, taste/quality, nutrition/health benefits, cost, and safety of fresh-cut fruit and vegetables. Sixty-three percent of respondents reported eating five to six servings of fruit and vegetables a day. This group most frequently consumed fresh-cut fruit as snacks or dessert, and vegetables in stir-fry dishes or salads or cooked with meals. In general, fresh-cut fruit and vegetables were perceived as convenient, safe, and nutritious. While approximately 50% of participants felt fresh-cut produce did not differ in taste from whole fresh produce, almost the same number considered whole fresh produce superior in taste. Dietitians have a generally positive perception of fresh-cut products; however, there is uncertainty about the nutritional value, cost/benefit, and use of the products. Dietitians require more information on the nutrient value of these products and on suggested alternative uses. Attention should be paid to developing fresh-cut products that have good sensory quality.

  10. Modelling RGB colour aspects and translucency of fresh-cut tomatoes

    NARCIS (Netherlands)

    Moreira Lana, M.; Tijskens, L.M.M.; Kooten, van O.

    2006-01-01

    Translucency is one of the major problems in fresh-cut fruit. This phenomenon seriously limits the use of fruit by the fresh-cut industries. Techniques for measuring translucency in this kind of product are not readily available. As a consequence, the processes that are important in the development

  11. Fungal infections of fresh-cut fruit can be detected by the gas chromatography-mass spectrometric identification of microbial volatile organic compounds.

    Science.gov (United States)

    Lloyd, Steven W; Grimm, Casey C; Klich, Maren A; Beltz, Shannon B

    2005-06-01

    There is a large and rapidly growing market for fresh-cut fruit. Microbial volatile organic compounds indicate the presence of fungal or bacterial contamination in fruit. In order to determine whether microbial volatile organic compounds can be used to detect contamination before fruit becomes unmarketable, pieces of cantaloupe, apple, pineapple, and orange were inoculated with a variety of fungal species, incubated at 25 degrees C, then sealed in glass vials. The volatiles were extracted by headspace solid-phase microextraction and analyzed by gas chromatography-mass spectrometry. Forty-five compounds were identified that might serve as unique identifiers of fungal contamination. Fungal contamination can be detected as early as 24 h after inoculation.

  12. Effect of ripeness stage during processing on Listeria monocytogenes growth on fresh-cut 'Conference' pears.

    Science.gov (United States)

    Colás-Medà, Pilar; Abadias, Maribel; Alegre, Isabel; Usall, Josep; Viñas, Inmaculada

    2015-08-01

    There are several factors that affect the shelf life of fresh-cut fruit, including the cultivar, the ripeness stage of the fruit during processing and the fruit's storage atmosphere and temperature. The effect of fruit ripeness during processing on the survival and growth of Listeria monocytogenes on fresh-cut 'Conference' pear slices at different temperatures (5, 10 and 20 °C) was studied. The four ripeness stages studied in this work (assessed by a fruit's firmness) were mature-green (54-60 N), partially ripe (43-53 N), ripe (31-42 N) and overripe (fresh-cut pear, the growth potential of L. monocytogenes increased with increasing temperature. A pear's ripeness stage during processing is an important consideration to ensure the quality of a fresh-cut pear, but it is not as important for preventing L. monocytogenes growth at common storage temperatures. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Systematic Study of the Content of Phytochemicals in Fresh and Fresh-Cut Vegetables

    Directory of Open Access Journals (Sweden)

    María Isabel Alarcón-Flores

    2015-05-01

    Full Text Available Vegetables and fruits have beneficial properties for human health, because of the presence of phytochemicals, but their concentration can fluctuate throughout the year. A systematic study of the phytochemical content in tomato, eggplant, carrot, broccoli and grape (fresh and fresh-cut has been performed at different seasons, using liquid chromatography coupled to triple quadrupole mass spectrometry. It was observed that phenolic acids (the predominant group in carrot, eggplant and tomato were found at higher concentrations in fresh carrot than in fresh-cut carrot. However, in the case of eggplant, they were detected at a higher content in fresh-cut than in fresh samples. Regarding tomato, the differences in the content of phenolic acids between fresh and fresh-cut were lower than in other matrices, except in winter sampling, where this family was detected at the highest concentration in fresh tomato. In grape, the flavonols content (predominant group was higher in fresh grape than in fresh-cut during all samplings. The content of glucosinolates was lower in fresh-cut broccoli than in fresh samples in winter and spring sampling, although this trend changes in summer and autumn. In summary, phytochemical concentration did show significant differences during one-year monitoring, and the families of phytochemicals presented different behaviors depending on the matrix studied.

  14. Foodborne outbreaks and potential routes of contamination in fresh and fresh-cut fruits and vegetables

    Science.gov (United States)

    Outbreaks of Salmonella spp., Listeria monocytogenes, and Escherichia coli O157:H7 have been associated with mangoes, cantaloupes, and leafy green commodities, respectively. The 2011 outbreak of L. monocytogenes associated with the consumption of contaminated Rocky Ford cantaloupes was one of the m...

  15. Use of Pressure for Improving Storage Quality of Fresh-Cut Produce.

    Science.gov (United States)

    Izumi, Hidemi

    2015-01-01

    The microflora of fresh-cut produce is comprised primarily of phytopathogenic and soilborne organisms, but the product could be contaminated with foodborne pathogens. Populations of bacteria, molds, and yeasts associated with fresh-cut produce decreased to non-detectable levels following a high pressure (HP) treatment of 400 MPa for 10 min at room temperature, except for spore-forming bacteria such as Bacillus spp. which were inactivated when subjected to 600 MPa at 60 °C for 10 min. The HP treatment of 400 MPa for 5-10 min at room temperature for fresh-cut lotus root and pineapple may be commercially feasible as an alternative to chemical sterilization and thermal blanching, respectively. The HP treatment reduced the epiphytic microorganisms of the products to non-detectable levels, and the microbial counts remained at the initial levels during storage at 1 °C with minimal changes in physicochemical and visual quality of the products. However, the HP treatment induced cellular disruption in plant tissue that contributed to the changes in appearance of several fresh-cut vegetables. To improve storage quality, combining lower pressures with complementary technologies should be useful for successful application of HP for other fresh-cut produce.

  16. Alginate- and gellan-based edible films for probiotic coatings on fresh-cut fruits.

    Science.gov (United States)

    Tapia, M S; Rojas-Graü, M A; Rodríguez, F J; Ramírez, J; Carmona, A; Martin-Belloso, O

    2007-05-01

    Alginate- (2% w/v) or gellan-based (0.5%) edible films, containing glycerol (0.6% to 2.0%), N-acetylcysteine (1%), and/or ascorbic acid (1%) and citric acid (1%), were formulated and used to coat fresh-cut apple and papaya cylinders. Water vapor permeability (WVP) was significantly higher (P fresh-cut fruits. Fresh-cut apple and papaya cylinders were successfully coated with 2% (w/v) alginate or gellan film-forming solutions containing viable bifidobacteria. WVP in alginate (6.31 and 5.52 x 10(-9) g m/Pa s m2) or gellan (3.65 and 4.89 x 10(-9) g m/Pa s m2) probiotic coatings of papaya and apple, respectively, were higher than in the corresponding cast films. The gellan coatings and films exhibited better water vapor properties in comparison with the alginate coatings. Values > 10(6) CFU/g B. lactis Bb-12 were maintained for 10 d during refrigerated storage of fresh-cut fruits, demonstrating the feasibility of alginate- and gellan-based edible coatings to carry and support viable probiotics on fresh-cut fruit.

  17. Analytical and Mathematical Determination of Shelf-life of Fresh-cut Red Cabbage

    Directory of Open Access Journals (Sweden)

    Fulya Şimşek

    2017-04-01

    Full Text Available Fresh-cut fruits and vegetables have longer shelf lives when appropriate packaging materials having proper permeability properties are used. For this reason eight different packaging materials having different permeability properties were used and it was aimed to determine the appropriate packaging material and analytical and mathematical shelf lives of fresh cut red cabbage. Head space analysis, microbiological and sensorial analysis together with pH, weight loss (% and colour analysis were performed. As a result of the study, it was determined that low density polyethylene (LDPE film having 20 µm of thickness and 12276 cc/m2-day of oxygen permeability was determined as the most suitable packaging material for packaging of fresh-cut red cabbage. Mathematical microbiological shelf life was determined as 12.33 days and both analytical microbiological and sensorial shelf lives were determined as 12 days. It was shown that Gompertz equation can be used in determination of microbiological shelf life of fresh-cut red cabbage since the analytical and mathematical shelf life results fit to each other. Also, the equation that can be used in calculation of shelf life of fresh-cut red cabbage when packaged with AYPE film having 12276 cc/m2-day oxygen permeability was determined as log(Nt/N0 = 6,83 × exp{-exp{[(0,80*e(6,83-t/6,83]+1}}.

  18. Effect of deastringency treatment of intact persimmon fruits on the quality of fresh-cut persimmons.

    Science.gov (United States)

    Chung, Hun-Sik; Kim, Han-Soo; Lee, Young-Guen; Seong, Jong-Hwan

    2015-01-01

    The changes in the quality characteristics of the fresh-cut products prepared from intact 'Cheongdobansi' persimmons treated with different deastringency methods (nontreated, carbon dioxide gas, warm water, ethanol vapour) have been investigated for 6 days at 10 °C. Flesh firmness of the persimmons decreased after ethanol vapour treatment. The decrease in L(∗) value and flesh firmness in the slices prepared from persimmons treated with warm water was retarded. Soluble solids content and titratable acidity of the persimmons decreased after all deastringency treatments. Soluble tannins and radical scavenging activity of the slices from untreated persimmons were maintained at higher concentrations, unlike slices from astringency-removed persimmons. These results suggest that pre-slicing deastringency treatments affect the characteristics of fresh-cut persimmons, and that warm-water treatment could be a useful method to control the browning and softening of fresh-cut persimmons. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Effect of Storage Temperature on the Quality of Fresh-cut Cattail

    Institute of Scientific and Technical Information of China (English)

    Hesheng HUANG; Haiping WANG; PianPian ZHANG

    2015-01-01

    Fresh-cut cattail was extremely not resistant to store at room temperature. In the first day, it began to etiolate and rot, the fiber content increased, but the vi-tamin C content and reducing sugar content decreased. The aerobic bacterial count increased, the weight loss rate sharply increased, and the sensory quality and food value were gradual y lost. Low temperature storage could decrease the loss of vita-min C and reducing sugar of fresh-cut cattail, reduce the weight loss rate and delay the increase of fiber content, maintain the water and nutrient of fresh-cut cattail, and the storage effect of 0 ℃ was better than 4 ℃.

  20. Cantaloupe Insects: Ecology and Control

    Science.gov (United States)

    Cantaloupe (Cucumis melo L.) is a member of the Cucurbitaceae family that includes squash, cucumber, watermelon, pumpkin and gourds along with many wild species. Numerous varieties of cantaloupe are grown in temperate and tropical zones across the globe and depend on honeybees for pollination and h...

  1. Impact of mixtures of different fresh-cut fruits on respiration and ethylene production rates.

    Science.gov (United States)

    Mahajan, Pramod V; Luca, Alexandru; Edelenbos, Merete

    2014-07-01

    Packaging and storage of fresh-cut fruits and vegetables are a challenging task, since fresh produce continue to respire and senesce after harvest and processing accelerates the physiological processes. The response on respiration and ethylene production rates of fresh produce to changes in O2 and CO2 concentrations and temperature has been extensively studied for whole fruits but literature is limited on processed and mixed fresh-cut fruits. This study aimed to investigate the effects of mixing various proportions of fresh-cut fruits (melon chunks, apple slices, and pineapples cubes) on respiration and ethylene production rates and to develop predictive models for modified atmosphere packaging. The experiment was designed according to a simplex lattice method and respiration and ethylene production rates were measured at 10 °C. Results showed that single component pineapple cubes, apple slices, and melon chunks, in this order, had significant constant coefficients (P = 0.05) and the greatest impact on respiration rate while the interactive binary and tertiary coefficients were insignificant. For ethylene production rates, single component apple slices, melon chunks, and pineapple cubes, and their 3-component mixtures, in this order, had significant constant coefficients (P = 0.05) while binary coefficients were insignificant. Mathematical models were developed and validated; the cubical model was the best to describe the influence of proportion of fruit on respiration and ethylene production rates, however, considering simplicity the linear part of the model is recommended to quantify respiration and ethylene production rates of mixed fresh-cut fruits. This research helps to quantify the ethylene production and respiration rates of multicomponent mixed fresh-cut fruit, which then can be used for packaging design of fresh-cut produce. © 2014 Institute of Food Technologists®

  2. Effects of cutting and maturity on antioxidant activity of fresh-cut tomatoes

    NARCIS (Netherlands)

    Moreira Lana, M.; Tijskens, L.M.M.; Kooten, van O.

    2005-01-01

    To investigate the changes in total antioxidant activity of fresh-cut tomato during storage, tomato fruits harvested at three different stages of maturity were cut into 7-mm thick slices and stored at 5°C. Intact (control) fruits were stored in the same conditions. The antioxidant activity was evalu

  3. Application of Kubelka - Munk analysis to the study of translucency in fresh-cut tomato

    NARCIS (Netherlands)

    Lana, M.M.; Hogenkamp, M.; Koehorst, R.B.M.

    2006-01-01

    In order to assess the development of translucency in fresh-cut tomato (Lycopersicum esculentum cv. Belissimo) during refrigerated storage, two experiments were conducted. In the first one, tomato slices obtained from fruits at breaker and at red stage were stored at 5 ± 0.5 °C and monitored at regu

  4. Acidified sodium chlorite optimisation assessment to improve quality of fresh-cut tatsoi baby leaves.

    Science.gov (United States)

    Tomás-Callejas, Alejandro; López-Velasco, Gabriela; Artés, Francisco; Artés-Hernández, Francisco

    2012-03-15

    The fresh-cut industry commonly uses sodium hypochlorite (NaClO) for disinfection. However, there are certain problems related to its use, and acidified sodium chlorite (ASC) could be an alternative sanitiser to replace it. There is limited research evaluating the effect of ASC on the overall quality of fresh-cut produce, especially sensory quality. In this study the decontamination efficacy and quality attribute effects of ASC on fresh-cut tatsoi after application and during storage were investigated. Tatsoi baby leaves were minimally processed at 8 °C and stored under passive modified atmosphere packaging for up to 11 days at 5 and 10 °C. Low to moderate doses of ASC (100-500 mg L⁻¹) showed an initial antimicrobial efficacy on natural microflora and Escherichia coli as effective as that of NaClO. Regarding contact time, ASC was effective in reducting the E. coli population during the first 30 s of washing, and an increase in contact time did not improve the antimicrobial effect. Sensory quality attributes were well kept for up to 11 days at 5 °C but for only 5 days at the abusive temperature of 10 °C. ASC provides an alternative sanitising technique to NaClO for maintaining the quality and safety of fresh-cut tatsoi baby leaves for up to 11 days at 5 °C. Copyright © 2011 Society of Chemical Industry.

  5. Assessment and speciation of chlorine demand in fresh-cut produce wash water

    Science.gov (United States)

    Production of high quality, fresh-cut produce is a key driver for the produce industry. A critical area of concern is the chlorinated wash water used during post-harvest processing in large industrial processing facilities. Predominantly using a batch process, wash water is recycled over 8hr shift...

  6. Effects of cutting and maturity on antioxidant activity of fresh-cut tomatoes

    NARCIS (Netherlands)

    Moreira Lana, M.; Tijskens, L.M.M.

    2006-01-01

    To investigate the changes in total antioxidant activity of fresh-cut tomato during storage, tomato fruits harvested at three different stages of maturity were cut into 7-mm thick slices and stored at 5 °C. Intact fruits were stored in the same conditions as a control. The antioxidant activity was e

  7. Native microflora in fresh-cut processing plants and their potentials of biofilm formation

    Science.gov (United States)

    Representative food contact and non-food contact surfaces in two mid-sized fresh cut processing facilities were sampled for microbiological analyses post routine daily sanitization. Mesophilic and psychrotrophic bacteria on the sampled surfaces were isolated by plating on non-selective bacterial med...

  8. Surface treatments and coatings to maintain fresh cut mango quality in storage

    Science.gov (United States)

    Edible coatings prevent moisture loss and may decrease gas exchange, thereby retaining moisture and flavor of fresh-cut fruit. Previous experiments showed that carboxymethylcellulose (CMC) with added maltodextrin maintained visual quality of stored mango slices also treated with calcium ascorbate an...

  9. Modelling quality of fresh-cut tomato based on stage of maturity and storage conditions

    NARCIS (Netherlands)

    Moreira Lana, M.

    2005-01-01

    Fresh-cut or minimally processed vegetables are those which have been trimmed and/or peeled and/or cut into 100% usable product and still maintain freshness. Contrary to other processing methods (freezing, canning and drying for example) the minimal processing operations reduce the shelf life in rel

  10. Effects of cutting and maturity on antioxidant activity of fresh-cut tomatoes

    NARCIS (Netherlands)

    Moreira Lana, M.; Tijskens, L.M.M.

    2006-01-01

    To investigate the changes in total antioxidant activity of fresh-cut tomato during storage, tomato fruits harvested at three different stages of maturity were cut into 7-mm thick slices and stored at 5 °C. Intact fruits were stored in the same conditions as a control. The antioxidant activity was e

  11. Pre-Harvest light intensity affects shelf-Life of fresh-cut lettuce

    NARCIS (Netherlands)

    Witkowska, I.M.; Woltering, E.J.

    2010-01-01

    The industry of fresh-cut produce is continuously growing due to increasing demand for fresh, healthy and convenient foods. However, processing of vegetables accelerates quality deterioration due to structural, physiological and biochemical changes. Therefore, the value of the produce to the consume

  12. Modelling quality of fresh-cut tomato based on stage of maturity and storage conditions

    NARCIS (Netherlands)

    Moreira Lana, M.

    2005-01-01

    Fresh-cut or minimally processed vegetables are those which have been trimmed and/or peeled and/or cut into 100% usable product and still maintain freshness. Contrary to other processing methods (freezing, canning and drying for example) the minimal processing operations reduce the shelf life in rel

  13. Detection of decay in fresh-cut lettuce using hyperspectral imaging and chlorophyll fluorescence imaging

    Science.gov (United States)

    Fresh-cut lettuce sold in modified atmosphere packaging (MAP) is a desirable, but highly perishable product. Decay of tissue can start a few days after processing and may be difficult to detect by quick visual observation. A system for early detection of decay and gradual evaluation of its progress ...

  14. Modelling quality of fresh-cut tomato based on stage of maturity and storage conditions

    NARCIS (Netherlands)

    Moreira Lana, M.

    2005-01-01

    Fresh-cut or minimally processed vegetables are those which have been trimmed and/or peeled and/or cut into 100% usable product and still maintain freshness. Contrary to other processing methods (freezing, canning and drying for example) the minimal processing operations reduce the shelf life in

  15. Application of Kubelka - Munk analysis to the study of translucency in fresh-cut tomato

    NARCIS (Netherlands)

    Lana, M.M.; Hogenkamp, M.; Koehorst, R.B.M.

    2006-01-01

    In order to assess the development of translucency in fresh-cut tomato (Lycopersicum esculentum cv. Belissimo) during refrigerated storage, two experiments were conducted. In the first one, tomato slices obtained from fruits at breaker and at red stage were stored at 5 ± 0.5 °C and monitored at regu

  16. Edible coating as carrier of antimicrobial agents to extend the shelf life of fresh-cut apples

    Science.gov (United States)

    Edible coatings with antimicrobial agents can extend shelf-life of fresh-cut fruits. The effect of lemongrass, oregano oil and vanillin incorporated in apple puree-alginate edible coatings, on shelf-life of fresh-cut 'Fuji' apples, was investigated. Coated apples were packed in air filled polypropyl...

  17. Dual effectiveness of sodium chlorite for enzymatic browning inhibition and Escherichia coli inactivation on fresh-cut apples

    Science.gov (United States)

    This study investigated the dual effectiveness of sodium chlorite (SC) for browning inhibition and microbial inactivation on fresh-cut apples. The SC treatment exhibited a strong inhibition on browning reaction of fresh-cut Red Delicious apples during cold storage. Test results from examination of t...

  18. Application of chlorophyll fluorescence imaging and hyperspectral imaging in evaluation of decay in fresh-cut lettuce

    Science.gov (United States)

    Lettuce (Lactuca sativa L.) is commercially the most popular leafy vegetable whose leaves are usually consumed raw. Cleaned, cored, and chopped (fresh-cut) lettuce is a desirable, but highly perishable product. Modified atmosphere packaging (MAP) has been introduced to maintain quality of fresh-cut ...

  19. Ethanol vapor and saprophytic yeast treatments reduce decay and maintain quality of intact and fresh-cut cherries

    Science.gov (United States)

    The objective of this study was to evaluate the use of an ethanol vapor release pad and a saprophytic yeast (Cryptococcus infirmo-miniatum) to reduce decay and maintain postharvest quality of intact or fresh-cut sweet cherries (Prunus avium L.) cv. Lapins and Bing. Intact or fresh-cut fruit were pac...

  20. Retention of Quality and Nutritional Value of Thirteen Fresh-cut Vegetables Treated with Low Dose Radiation

    Science.gov (United States)

    The recent outbreaks associated with consumption of spinach, lettuce and tomato have resulted in much concern over the safety of fresh-cut vegetables. The industry is in need of a “kill” step to ensure the safety of fresh-cut vegetables. Many studies have demonstrated that a dose of 1 kGy radiatio...

  1. Discrimination methods of biological contamination on fresh-cut lettuce based on VNIR and NIR hyperspectral imaging

    Science.gov (United States)

    Multispectral imaging algorithms were developed using visible-near-infrared (VNIR) and near-infrared (NIR) hyperspectral imaging (HSI) techniques to detect worms on fresh-cut lettuce. The optimal wavebands that detect worm on fresh-cut lettuce for each type of HSI were investigated using the one-way...

  2. Sensory characteristics and consumer acceptance and purchase intention toward fresh-cut potatoes.

    Science.gov (United States)

    Montouto-Graña, Mónica; Cabanas-Arias, Sonia; Porto-Fojo, Silvia; Vázquez-Odériz, Ma Lourdes; Romero-Rodríguez, Ma Angeles

    2012-01-01

    For a new product to succeed in the market, it must be accepted by consumers. This study investigates consumer opinions on fresh-cut potatoes packaged under vacuum and under a modified atmosphere using home use tests. The data obtained were related to demographic characteristics and patterns of consumption and to purchase intention toward potatoes and other vegetables. The sensory characteristics evaluated by a panel of assessors trained in the sensory evaluation of potato were also considered. The results indicate that although both products were accepted by the consumer, vacuum-packed potatoes received slightly higher ratings and more consumers intended to purchase this product. The fresh-cut potato packaged under vacuum is a product with all the sensory characteristics that will be accepted by the consumers. The adaptation to the productive process at the industrial level, it can be performed with enough guarantees that the product will definitely be purchased by the consumers. © 2011 Institute of Food Technologists®

  3. Connecting fresh cut chain actors, from seed to produce - a European perspective

    DEFF Research Database (Denmark)

    Deleuran, Lise Christina

    2011-01-01

    structured interviews in the supply chain and the emphasis and choice of seed source in these productions are highlighted. Changes in consumer behavior towards more and more convenience food might further increase consumption of these product formats, however, consumer demand for local and/or organic produce...... raises the need to enhance the supply availability. At present only a very limited assortment of organic fresh-cut products is available for Danish consumers. Without import through commercialized chains, the selection of organic fresh-cut produce would be close to zero....... countries this segment is advanced and the supply chain compartmentalized. Parallels in respect to chain structures are therefore at present mainly drawn from other leafy fresh produce productions. Present approaches for securing year round supply of quality leafy vegetables were identified through...

  4. The membrane may be an important factor in browning of fresh-cut pear.

    Science.gov (United States)

    Li, Zhenghong; Zhang, Yuxing; Ge, Huibo

    2017-09-01

    Surface browning is an important cause of deterioration of fresh-cut fruit during postharvest handling. In this paper, four pear cultivars with different extents of natural browning were selected to analyse the factors involved in browning. The main results are as follows: the lipoxygenase (LOX) activity of 'Mantianhong' and 'Yali' pears was higher accompanied by a stronger degree of browning, while the LOX activity in 'Xueqing' and 'Xinli 7' pears was lower, with less browning. A higher unsaturated fatty acid ratio of pear resulted in reduced browning. The cell membranes disappeared 30min after being cut in 'Mantianhong' pear, which browns easily; however, the cell membranes were still intact 30min after being cut in 'Xueqing' pear, which does not brown easily. Therefore, it can be assumed that the stability of the cell membrane plays an important role in inhibiting browning of fresh-cut pears. Copyright © 2017. Published by Elsevier Ltd.

  5. Biodegradable PLA (polylactic acid) hinged trays keep quality of fresh-cut and cooked spinach.

    Science.gov (United States)

    Botondi, Rinaldo; Bartoloni, Serena; Baccelloni, Simone; Mencarelli, Fabio

    2015-09-01

    This work examines the effects of packaging using two different polymeric trays with hinged lids, polyethylene terephthalate (PET) and polylactic acid (PLA), on fresh-cut and cooked spinach (Spinacia oleracea). Samples were stored in a cold room for 16 days at 4 °C. Chemical (total pigments, total polyphenols, ascorbic acid, antioxidant activity), physical (water activity), technological (colour evaluation), sensorial (aroma, visual appearance and water accumulation) and microbial (total aerobic mesophilic and psychrotrophic counts) parameters were tested. Both polymeric trays maintained the overall quality of fresh spinach for 6 days but spinach stored in PLA trays maintained its flavour longer. A significant increase in total polyphenols, antiradical activity, total carotenoids as well as a decrease in ascorbic acid in fresh spinach was observed in the first 3 days of storage in both samples. Unfortunately, the PLA package accumulated condensed water. The total microbial load of fresh-cut spinach reached about 6.3-7.3 log CFU g(-1) within 8 days. Cooked spinach packed in PLA and PET polymeric hinged trays showed the same behaviour as fresh spinach in terms of quality and shelf life. In conclusion, PLA plastic hinged trays can be used for packaging fresh-cut and cooked cut spinach, but the problem of condensed water must be solved.

  6. Guidelines To Validate Control of Cross-Contamination during Washing of Fresh-Cut Leafy Vegetables.

    Science.gov (United States)

    Gombas, D; Luo, Y; Brennan, J; Shergill, G; Petran, R; Walsh, R; Hau, H; Khurana, K; Zomorodi, B; Rosen, J; Varley, R; Deng, K

    2017-02-01

    The U.S. Food and Drug Administration requires food processors to implement and validate processes that will result in significantly minimizing or preventing the occurrence of hazards that are reasonably foreseeable in food production. During production of fresh-cut leafy vegetables, microbial contamination that may be present on the product can spread throughout the production batch when the product is washed, thus increasing the risk of illnesses. The use of antimicrobials in the wash water is a critical step in preventing such water-mediated cross-contamination; however, many factors can affect antimicrobial efficacy in the production of fresh-cut leafy vegetables, and the procedures for validating this key preventive control have not been articulated. Producers may consider three options for validating antimicrobial washing as a preventive control for cross-contamination. Option 1 involves the use of a surrogate for the microbial hazard and the demonstration that cross-contamination is prevented by the antimicrobial wash. Option 2 involves the use of antimicrobial sensors and the demonstration that a critical antimicrobial level is maintained during worst-case operating conditions. Option 3 validates the placement of the sensors in the processing equipment with the demonstration that a critical antimicrobial level is maintained at all locations, regardless of operating conditions. These validation options developed for fresh-cut leafy vegetables may serve as examples for validating processes that prevent cross-contamination during washing of other fresh produce commodities.

  7. Fresh-cut pineapple as a new carrier of probiotic lactic acid bacteria.

    Science.gov (United States)

    Russo, Pasquale; de Chiara, Maria Lucia Valeria; Vernile, Anna; Amodio, Maria Luisa; Arena, Mattia Pia; Capozzi, Vittorio; Massa, Salvatore; Spano, Giuseppe

    2014-01-01

    Due to the increasing interest for healthy foods, the feasibility of using fresh-cut fruits to vehicle probiotic microorganisms is arising scientific interest. With this aim, the survival of probiotic lactic acid bacteria, belonging to Lactobacillus plantarum and Lactobacillus fermentum species, was monitored on artificially inoculated pineapple pieces throughout storage. The main nutritional, physicochemical, and sensorial parameters of minimally processed pineapples were monitored. Finally, probiotic Lactobacillus were further investigated for their antagonistic effect against Listeria monocytogenes and Escherichia coli O157:H7 on pineapple plugs. Our results show that at eight days of storage, the concentration of L. plantarum and L. fermentum on pineapples pieces ranged between 7.3 and 6.3 log cfu g(-1), respectively, without affecting the final quality of the fresh-cut pineapple. The antagonistic assays indicated that L. plantarum was able to inhibit the growth of both pathogens, while L. fermentum was effective only against L. monocytogenes. This study suggests that both L. plantarum and L. fermentum could be successfully applied during processing of fresh-cut pineapples, contributing at the same time to inducing a protective effect against relevant foodborne pathogens.

  8. Effect of carrot puree edible films on quality preservation of fresh-cut carrots

    Directory of Open Access Journals (Sweden)

    Wang X.

    2015-06-01

    Full Text Available The effect of edible films based on carrot puree, chitosan, corn starch, gelatin, glycerol and cinnamaldehyde on fresh-cut carrots was studied during storage. Several parameters, such as firmness, colour, weight loss, total carotenoids, total phenols, polyphenol oxidase (PPO activity and peroxidase (POD activity in coated carrots were determined at regular intervals and then compared with the uncoated carrots throughout the storage period. Significant and expected changes were observed in all carrot samples that were compared. The coating treatment significantly (P < 0.05 delayed the senescence, reduced the deterioration of exterior quality and retained total carotenoids well compared with control (P < 0.05. In addition, significant inhibition of PPO activity (P < 0.05 and POD activity (P < 0.05 as well as reduced accumulation of polyphenols (P < 0.05 were observed for all coated samples. All of these favourable responses induced by coating treatment on minimally processed fresh-cut carrots showed beneficial physiological effects, which would give some useful references to the fresh-cut fruit and vegetable processing industry and satisfy people’s requirements allowing for extending product shelf life without negatively affecting the sensory quality or acceptability.

  9. Folate content in fresh-cut vegetable packed products by 96-well microtiter plate microbiological assay.

    Science.gov (United States)

    Fajardo, Violeta; Alonso-Aperte, Elena; Varela-Moreiras, Gregorio

    2015-02-15

    Ready-to-eat foods have nowadays become a significant portion of the diet. Accordingly, nutritional composition of these food categories should be well-known, in particular its folate content. However, there is a broad lack of folate data in food composition tables and databases. A total of 21 fresh-cut vegetable and fruit packed products were analysed for total folate (TF) content using a validated method that relies on the folate-dependent growth of chloramphenicol-resistant Lactobacillus casei subspecies rhamnosus (NCIMB 10463). Mean TF content ranged from 10.0 to 140.9μg/100g for the different matrices on a fresh weight basis. Higher TF quantity, 140.9-70.1μg/100g, was found in spinach, rocket, watercress, chard and broccoli. Significant differences were observed between available data for fresh vegetables and fruits from food composition tables or databases and the analysed results for fresh-cut packed products. Supplied data support the potential of folate-rich fresh-cut ready-to-eat vegetables to increase folate intake significantly. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Identification of innovative potential quality markers in rocket and melon fresh-cut produce.

    Science.gov (United States)

    Cavaiuolo, Marina; Cocetta, Giacomo; Bulgari, Roberta; Spinardi, Anna; Ferrante, Antonio

    2015-12-01

    Ready-to-eat fresh cut produce are exposed to pre- and postharvest abiotic stresses during the production chain. Our work aimed to identify stress responsive genes as new molecular markers of quality that can be widely applied to leaves and fruits and easily determined at any stage of the production chain. Stress responsive genes associated with quality losses were isolated in rocket and melon fresh-cut produce and their expression levels analyzed by quantitative real time PCR (qRT-PCR) at different time points after harvest at 20 °C and 4 °C. qRT-PCR results were supported by correlation analysis with physiological and biochemical determinations evaluated at the same conditions such as chlorophyll a fluorescence indices, total, reducing sugars, sucrose, ethylene, ascorbic acid, lipid peroxidation and reactive oxygen species. In both species the putative molecular markers increased their expression soon after harvest suggesting a possible use as novel and objective quality markers of fresh-cut produces.

  11. Efficacy of sodium hypochlorite and acidified sodium chlorite in preventing browning and microbial growth on fresh-cut produce.

    Science.gov (United States)

    Sun, Shih Hui; Kim, Su Jin; Kwak, Soo Jin; Yoon, Ki Sun

    2012-09-01

    The use of suitable sanitizers can increase the quality of fresh-cut produce and reduce the risk of foodborne illnesses. The objective of this study was to compare the washing effects of 100 mg/L sodium hypochlorite (SH) and 500 mg/L acidified sodium chlorite (ASC) on the prevention of enzymatic browning and the growth of microbial populations, including aerobic plate counts, E. coli, and coliforms, throughout storage at 4°C and 10°C. Fresh-cut zucchini, cucumbers, green bell peppers, and root vegetables such as potatoes, sweet potatoes, carrots, and radishes were used. Compared to SH washing, ASC washing significantly (p<0.05) reduced microbial contamination on the fresh-cut produce and prevented browning of fresh-cut potatoes and sweet potatoes during storage. More effective inhibition of aerobic plate counts and coliforms growth was observed on fresh-cut produce treated with ASC during storage at 10°C. Polyphenol oxidase (PPO) activity of fresh-cut potatoes and sweet potatoes was more effectively inhibited after washing with ASC. The use of 500 mg/L ASC can provide effective antimicrobial and anti-browning treatments of fresh-cut produce, including processed root vegetables.

  12. Impact of starch-based emulsions on the antibacterial efficacies of nisin and thymol in cantaloupe juice.

    Science.gov (United States)

    Sarkar, Preetam; Bhunia, Arun K; Yao, Yuan

    2017-02-15

    The use of antimicrobial compounds to prevent foodborne pathogens from contaminating fresh-cut produce has received broad attentions; however, the applications of these compounds are hindered by their rapid depletion in foods. To prolong their efficacies, the use of delivery systems is essential. In this study, oil-in-water emulsions formed using starch octenyl succinate (starch-OS) were used to stabilize nisin and thymol in cantaloupe juice-containing fluid. Listeria monocytogenes V7 and Salmonella enterica serovar Typhimurium were used as model pathogens to evaluate the antimicrobial activities of nisin and thymol formulations in cantaloupe juice. The results showed that the emulsions had much greater capability to retain nisin and thymol over the storage and displayed much greater effect to inhibit Listeria and Salmonella than non-emulsion, aqueous formulations. Starch-OS based emulsions not only retained nisin and thymol activities separately, but also exhibited their cooperative antibacterial effects. Copyright © 2016. Published by Elsevier Ltd.

  13. Changes in Ascorbic Acid Content, Antioxidant Capacity and Sensory Quality of Fresh-cut Mangosteens During Storage

    Directory of Open Access Journals (Sweden)

    Supranee MANURAKCHINAKORN

    2004-06-01

    Full Text Available Fresh-cut mangosteens, stored in modified atmosphere packaging (MAP; 5% O2 + 9% CO2, in vacuum packaging (VAC and in air (AIR were examined for ascorbic acid content, antioxidant capacity and sensory quality during 14 days of storage at 4oC. After 4 days-storage, fresh-cut fruits with MAP resulted in better retention of ascorbic acid and antioxidant capacity than those stored in AIR throughout the storage. Furthermore, there were no significant differences in ascorbic acid contents between fruits stored in MAP and VAC, as well as antioxidant capacities, during the remaining period of storage. Fresh-cut fruits with MAP treatment obtained the highest sensory scores, compared with other treatments, throughout the entire period of storage. Fresh-cut mangosteens stored in MAP resulted in the best overall retention of ascorbic acid, antioxidant capacity and sensory quality.

  14. Potential Application of Ascorbic Acid, Citric Acid and Oxalic Acid for Browning Inhibition in Fresh-Cut Fruits and Vegetables

    Directory of Open Access Journals (Sweden)

    Weerayuth SUTTIRAK

    2010-01-01

    Full Text Available The market for fresh-cut fruits and vegetables has grown rapidly in recent decades as a result of their freshness, convenience, and human health benefits. However, fresh fruits and vegetables deteriorate very rapidly after processing, especially cut-surface browning resulting from wound-induced physiological and biochemical changes. The application of antibrowning agents is one of the most effective methods for controlling the enzymatic browning reaction in fresh-cut fruits and vegetables. This article reviews the use of nature identical antibrowning agents, which are generally recognized as safe (GRAS including ascorbic acid, citric acid and oxalic acid for preventing browning in fresh-cut fruits and vegetables. Factors affecting inhibitory efficiency of the antibrowning agents and synergistic effects of the mixtures in various fresh-cut fruits and vegetables are presented.

  15. Antioxidant enrichment and antimicrobial protection of fresh-cut fruits using their own byproducts: looking for integral exploitation.

    Science.gov (United States)

    Ayala-Zavala, J F; Rosas-Domínguez, C; Vega-Vega, V; González-Aguilar, G A

    2010-10-01

    Fresh-cut fruit consumption is increasing due to the rising public demand for convenience and awareness of fresh-cut fruit's health benefits. The entire tissue of fruits and vegetables is rich in bioactive compounds, such as phenolic compounds, carotenoids, and vitamins. The fresh-cut fruit industry deals with the perishable character of its products and the large percentage of byproducts, such as peels, seeds, and unused flesh that are generated by different steps of the industrial process. In most cases, the wasted byproducts can present similar or even higher contents of antioxidant and antimicrobial compounds than the final produce can. In this context, this hypothesis article finds that the antioxidant enrichment and antimicrobial protection of fresh-cut fruits, provided by the fruit's own byproducts, could be possible.

  16. Examination of Bacteriophage as a Biocontrol Method for Salmonella on Fresh-Cut Fruit: A Model Study

    National Research Council Canada - National Science Library

    Leverentz B; Conway W.S; Alavidze Z; Janisiewicz W.J; Fuchs Y; Camp M.J; Chighladze E; Sulakvelidze A

    2001-01-01

    .... However, fresh-cut fruits and vegetables may represent an increased food safety concern because of the absence or damage of peel and rind, which normally help reduce colonization of uncut produce...

  17. Effects of postharvest curing treatment on flesh colour and phenolic metabolism in fresh-cut potato products.

    Science.gov (United States)

    Wang, Qingguo; Cao, Yu; Zhou, Lili; Jiang, Cai-Zhong; Feng, Yanyan; Wei, Shaochong

    2015-02-15

    The flesh colour and phenolic metabolism in potato tuber during curing and after cut were investigated. Result indicated that postharvest curing not only changed phenolic metabolism during curing, but also improved fresh-cut colour for 12 days after fresh cut. Significantly lower PAL and higher phenolic content and PPO activities during curing treatment and fresh-cut potatoes were detected compared to the control, which lead to the lower browning in the slices from curing treated potatoes. HPLC analysis revealed that amounts of total phenolics, chlorogenic acid, gallic acid and protocatechuic acid were induced by curing and highly accumulated in the curing treated potatoes. Our results demonstrated that phenolic metabolism played an important role in the control of browning of fresh cut potato after curing.

  18. Potential Application of Ascorbic Acid, Citric Acid and Oxalic Acid for Browning Inhibition in Fresh-Cut Fruits and Vegetables

    OpenAIRE

    Weerayuth SUTTIRAK; Supranee MANURAKCHINAKORN

    2010-01-01

    The market for fresh-cut fruits and vegetables has grown rapidly in recent decades as a result of their freshness, convenience, and human health benefits. However, fresh fruits and vegetables deteriorate very rapidly after processing, especially cut-surface browning resulting from wound-induced physiological and biochemical changes. The application of antibrowning agents is one of the most effective methods for controlling the enzymatic browning reaction in fresh-cut fruits and vegetables. Th...

  19. Application of heat treatment, edible coating and chemical dip as barriers to the conservation of fresh-cut vegetables

    OpenAIRE

    Escobar Hernández, Alejandro; Márquez Cardozo, Carlos Julio; Restrepo Flores, Claudia Estela; Cano Salazar, Jaime Andrés; Patiño Gómez, Jairo Humberto

    2014-01-01

    The fresh-cut vegetables consumption is increasing in the worldwide since its foray in the early 90s. The international association of fresh cut products, reported sales in 2000 of 12 billion dollars. The interest in feed quickly and healthy, has stimulated the development of vegetable fourth range, however their high metabolic activity reduces its stability and shelf life. It has promoted the adoption of technologies for minimally processed products that give them longer life and ensure the ...

  20. Effects of fresh Aloe vera gel coating on browning alleviation of fresh cut wax apple (Syzygium samarangenese) fruit cv. Taaptimjaan.

    Science.gov (United States)

    Supapvanich, S; Mitrsang, P; Srinorkham, P; Boonyaritthongchai, P; Wongs-Aree, C

    2016-06-01

    The effect of natural coating by using fresh Aloe vera (A. vera) gel alleviating browning of fresh-cut wax apple fruits cv. Taaptimjaan was investigated. The fresh-cut fruits were dipped in fresh A. vera gel at various concentrations of 0, 25, 75 or 100 % (v/v) for 2 min at 4 ± 1 °C for 6 days. Lightness (L*), whiteness index (WI), browning index (BI), total color difference (ΔE*), sensorial quality attributes, total phenolic (TP) content, antioxidant activity and polyphenol oxidase (PPO) and peroxidase (POD) activities were determined. During storage, L* and WI of the fresh-cut fruits surface decreased whilst their BI and ΔE* increased. A. vera coating maintained the L* and WI and delayed the increase in BI and ΔE*, especially at 75 % A. vera dip. The fresh-cut fruits dipped in 75 % A. vera had the lowest browning score, the highest acceptance score and delayed the increase in TP content and PPO activity. However POD activity was induced by A. vera coating. Antioxidant activity had no effect on browning incidence of the fresh-cut fruits. Consequently, A. vera gel coating could maintain quality and retarded browning of fresh-cut wax apple fruits during storage.

  1. Alternative sanitizers to chlorine for use on fresh-cut "Galia" (Cucumis melo var. catalupensis) melon.

    Science.gov (United States)

    Silveira, A C; Conesa, A; Aguayo, E; Artes, F

    2008-11-01

    Chlorine is commonly used to reduce microbial load in fresh-cut vegetables. However, the production of chlorinated organic compounds, such as trihalomethanes, which are potential carcinogens, has created the need to investigate the efficiency of nontraditional sanitizers and alternative techniques. The effects of 4 novel sanitizers were tested in fresh-cut "Galia" melon: chlorine dioxide (ClO(2)) at 3 mg/L, peracetic acid (PAA) at 80 mg/L, hydrogen peroxide (H(2)O(2)) at 50 mg/L, and nisin at 250 mg/L plus EDTA 100 mg/L (nisin + EDTA). A chlorine treatment (NaOCl at 150 mg/L) was used as a control. Pieces of melon were packed in polypropylene trays under passive modified atmosphere (3 to 4 kPa of O(2) and 10 to 11 kPa of CO(2)) and stored up to 10 d at 5 degrees C. Microbial growth, firmness, respiration rate, gas composition, sensory evaluation, color, total soluble solids (TSS), and tritable acidity (TA) were evaluated at days 0, 7, and 10. The novel sanitizers PAA, H(2)O(2), and nisin + EDTA, in the studied concentrations, reduced the microbial growth to a more efficient range than chlorine and ClO(2). In addition, those sanitizers delayed softness, did not affect the respiration rate, SST, or AT. The sensorial parameters were kept above the upper limit of marketability and they did not impart an "off flavor." These sanitizers maintained quality and shelf life of fresh-cut Galia melon for 10 d of storage at 5 degrees C. Nevertheless, other concentrations, in particular for ClO(2,) could be tested to study an extended shelf life in melon pieces.

  2. Effect of Different Sanitizers on Microbial, Sensory and Nutritional Quality of Fresh-Cut Jalapeno Peppers

    Directory of Open Access Journals (Sweden)

    Saul Ruiz-Cruz

    2010-01-01

    Full Text Available Problem statement: Sanitation is a critical step to insure safety of fresh-cut produce. The inadequacies of chlorine, currently used as a sanitizer, have stimulated interest in finding safer, more effective sanitizers, however little is known on the impact of these novel sanitizers on sensory and nutrimental quality of the treated products. Approach: The effect of four sanitizers: Sodium hypochlorite (OCl, Peroxiacetic Acid (PA, Acidified Sodium Chlorite (ASC and carvacrol on microbiological, sensorial and nutritional quality (total phenols, vitamin C and antioxidant capacity of fresh-cut jalapeno peppers stored at 5°C during 27 days was evaluated. Results: All sanitizers (except carvacrol maintained microbiological and overall quality of jalapeno peppers during 27 days. ASC (500 and 250 mg L-1 maintained the best microbiological and sensorial properties at the end of the storage period. Carvacrol, active ingredient of oregano essential oil, maintained shelf life for only 17 days. At the end of the storage period, all treatments showed a decrease of 12-43% respect to the initial vitamin C values. Total phenols and antioxidant capacity decreased in a lesser degree. None of the treatments except ACS 500 mg L-1, induced higher losses of vitamin C, total phenols or antioxidant capacity compared to control. Conclusion: Our results showed that all sanitizers were capable of controlling microbial growth without inducing major loss of antioxidant capacity and photochemical. Carvacrol was the only sanitizer that reduced sensory acceptability of fresh-cut jalapeno peppers, however carvacrol treated samples retained the highest levels of photochemical and antioxidant capacity. ASC was the most effective sanitizer even though it was used at concentrations lower that those currently approved by the FDA.

  3. Biodegradable packaging and edible coating for fresh-cut fruits and vegetables

    Directory of Open Access Journals (Sweden)

    Fernanda Galgano

    2015-03-01

    Full Text Available This work focuses on biodegradable packaging and edible coatings applied to fresh-cut fruits and vegetables and their effects on the product quality. Practical applications are mainly limited to the use of biodegradable materials that, however, do not allow full control of the product moisture loss. Better results can be achieved by the combined use of biodegradable packagings with edible coatings and recent research has shown that enrichment with silver montmorillonite nanoparticles may be a promising technique. However, the actual utilization of these materials is still limited, due to the high costs of the raw materials and the limited production.

  4. FRUIT JUICES AS AN ALTERNATIVE TECHNIQUE FOR CONSERVATION OF FRESH-CUT BANANA

    Directory of Open Access Journals (Sweden)

    ANDERSON ADRIANO MARTINS MELO

    2014-01-01

    Full Text Available Browning discoloration after cutting is detrimental for the quality of a number of fruits and vegetables, such as banana, apple, pear, potato, and some roots such as cassava, yam, and others. Browning and softening compromise banana after cut shelf-life in a few hours under cold storage. Therefore, anti-browning compounds have been applied to slices before packing. Some commonly used substances are calcium chloride, ascorbic acid, cysteine and citric acid, in immersed inchemical mixtures. Recent studies have demonstrated the possibility of preserving fresh-cut banana immersed in sweetened fruit juice for relatively longer periods, favoring commercialization. This type of conservation, although widely used in Brazil for fruit salads, consists of a more complex system in a physiological basis, requiring adjustment of the solution parameters, such as sugar concentration, pH and acidity, considering the viability and freshness of the plant tissue. In this short review, we discuss some experimental data and present a new method for preserving fresh-cut banana. Reduction of enzymatic activity, either in temporary dipping treatment or permanent immersion of banana slices is regarded as a key factor for maintaining its quality during cold storage.

  5. Antimicrobial and aromatic edible coating on fresh-cut pineapple preservation

    Directory of Open Access Journals (Sweden)

    Raphaela Gabri Bitencourt

    2014-06-01

    Full Text Available The present research aimed to develop an edible coating incorporated with mint essential oil, evaluate its effectiveness in inhibiting in vitro microbial development, and improve both quality and shelf-life of fresh-cut pineapple. Mint essential oil-containing edible coatings showed in vitro antimicrobial efficiency against Escherichia coli and Salmonella Enteritidis. Titratable acidity, pH, and texture were not affected (P>0.05 by coating or storage time. Mass loss was not higher than 1.0% after the 6th day of storage. No effect of storage time and coating on total soluble solids was observed. Mint essential oil-containing coatings inhibited the growth of yeasts and molds in fresh-cut pineapple. Compared to uncoated and control-coated samples, mint essential oil-containing coatings lessened psychrotrophic bacteria counts throughout storage. Counts of thermotolerant coliforms were not higher than 3.0MPN·g-1 in all treatments, whereas no Salmonella sp. was detected during the 6-day storage. Mint essential oil provided a strong flavor to the fruit, as shown by sensory evaluations.

  6. Volatile profile and physical, chemical, and biochemical changes in fresh cut watermelon during storage

    Directory of Open Access Journals (Sweden)

    Andréa Luiza Ramos Pereira Xisto

    2012-03-01

    Full Text Available Existing data about the aroma of fresh-cut watermelon and the metabolic changes that occur with minimal processing are scarce. Given the close relationship that exists between aroma, texture, and quality characteristics, it is necessary to investigate the changes in the volatile profile and texture of watermelon, a fruit extensively sold in supermarket chains throughout Brazil. The objective of this work was to analyze the volatile profile using solid phase microextraction (SPME as well as texture changes in fresh-cut watermelon stored at 5 °C for ten days. Chromatography associated with sensory analysis (sniffing led us to conclude that 9-carbon (C9 alcohols and aldehydes are the major responsible for the flavor and aroma of minimally processed watermelon stored at 5 ± 1 °C/90 ± 5% RH for ten days, and also that the aroma diminishes in intensity with storage, but it does not affect the final quality of the product. It was noted that the amount of drained liquid, soluble pectin, and weight loss increased during storage concurrently with a reduction in firmness and a structural breakdown of the cells. Pectin methyl esterase activity remained constant and polygalacturonase activity was not detected.

  7. Surface treatments and coatings to maintain fresh-cut mango quality in storage.

    Science.gov (United States)

    Plotto, Anne; Narciso, Jan A; Rattanapanone, Nithiya; Baldwin, Elizabeth A

    2010-10-01

    Edible coatings may extend fresh-cut fruit storage by preventing moisture loss and decreasing gas exchange. This study evaluated the effect of an antibrowning dip (calcium ascorbate, citric acid and N-acetyl-L-cysteine), followed or not with carboxymethylcellulose (CMC) or carrageenan coatings on quality of fresh-cut mangoes stored at 5 °C for up to 20 days. A fourth treatment, only used in one of four experiments, consisted of chitosan. Treatments were applied on 'Tommy Atkins', 'Kent' and 'Keitt' mangoes harvested from Homestead (FL), and on imported store-bought mangoes. The antibrowning dips maintained the best visual quality during storage for all cultivars, as indicated by higher b*, hue and L*. The CMC coating maintained similar visual quality, but carrageenan or chitosan decreased L* and b*. The antibrowning dip containing calcium ascorbate reduced firmness loss on cut pieces of 'Keitt', 'Kent' and store-bought mangoes. The antibrowning treatment maintained higher titratable acidity for 'Kent' and 'Keitt', resulting in lower sensory sweetness. This study with repeated experiments showed that calcium ascorbate with citric acid and N-acetyl-L-cysteine maintained cut mango slices attractiveness in storage by keeping light color in both varieties. The addition of a polysaccharide coating did not consistently improve quality.

  8. Quality Attributes of Fresh-Cut Coconut after Supercritical Carbon Dioxide Pasteurization

    Directory of Open Access Journals (Sweden)

    Giovanna Ferrentino

    2013-01-01

    Full Text Available The impact of supercritical CO2 (SC-CO2 process on the quality attributes of fresh-cut coconut has been investigated to establish the acceptability of SC-CO2 treated products by the consumers. Two process conditions, previously identified as optimal to reduce the microbial content of the product, were studied: 12 MPa, 40°C, 30 min and 12 MPa, 45°C, 15 min. The results highlighted that both conditions induced some effects on product attributes. After 30 min of treatment at 12 MPa and 40°C a decrease of lightness (8%, pH (13%, fat content (24%, total phenol content (29%, flavonoid compounds (49%, antioxidant capacity (30% and an increase of dry matter (11% and titratable acidity (51.1% were observed while polyphenol oxidase (PPO exhibited 35% and 98.5% inactivation. Peroxidase enzyme activity increased by 77.8% and 30.4% at 12 MPa, 40°C, 30 min and 12 MPa, 45°C, 15 min, respectively. Sensory evaluations revealed no significant differences in appearance, texture, taste, and aroma of treated fresh-cut coconut compared to the untreated. The study confirms the feasibility of SC-CO2 process for the pasteurization of fresh fruits with a firm structure and opens the door to the possibility of exploiting such a technology at industrial level.

  9. Using antibrowning agents to enhance quality and safety of fresh-cut avocado treated with intense light pulses.

    Science.gov (United States)

    Ramos-Villarroel, Ana Y; Martín-Belloso, Olga; Soliva-Fortuny, Robert

    2011-01-01

    The effect of antibrowning compounds on the color and firmness of fresh-cut avocado treated with intense light pulses (ILP), as well as their impact on the survival of Listeria innocua, was investigated in this study. Dipping solutions containing 2% (w/v) L-cysteine without ascorbic acid and combined with 1% (w/v) citric acid and 1% w/v calcium lactate most effectively preserved the initial color and texture of ILP-treated fresh-cut avocado. On the other hand, ILP treatments caused a reduction of more than 3 log cycles in the populations of L. innocua inoculated on fresh-cut avocado. Log reduction levels increased when antibrowning agents were combined with ILP treatments. In conclusion, the use of quality-stabilizing agents is a good option to guarantee both the microbiological safety of fresh-cut avocado treated with ILP as well as to improve its physical and chemical quality. Intense light pulses (ILP) have received considerable attention during the last years after its approval by the U.S. Food and Drug Administration (FDA) in 1996 as a decontamination method for food or food surfaces. This article presents relevant information regarding the effect of ILP treatments combined with quality-stabilizing compounds as a feasible alternative to improve the physical and chemical quality of fresh-cut avocado as well as to guarantee its microbiological safety. © 2011 Institute of Food Technologists®

  10. Edible coatings enriched with essential oils and their compounds for fresh and fresh-cut fruit.

    Science.gov (United States)

    Antunes, Maria D; Gago, Custodia M; Cavaco, Ana M; Miguel, Maria G

    2012-08-01

    Fresh fruit and vegetables consumption has increased in the past few years due to the enhanced awareness of consumers for healthy food. However, these products are highly perishable, and losses can be of great significance if postharvest correct management is not provided. Fresh-cut products are of increasing importance, since they are presented to the consumer in a state that allows for direct and immediate consumption. However, those products are even more perishable since cutting can induce a series of senescence associated responses to wounding, and are more susceptible to microbial spoilage. Edible coatings, which intend to reduce ripening processes and protect the fruit from water loss and spoilage may be a good way to enhance the shelf life of these products. More recently, the inclusion of additives into these edible coatings to increase their effectiveness, such as essential oils and their constituents with antimicrobial and antioxidant activities, has been reported and patented.

  11. Control of foodborne pathogens on fresh-cut fruit by a novel strain of Pseudomonas graminis.

    Science.gov (United States)

    Alegre, Isabel; Viñas, Inmaculada; Usall, Josep; Teixidó, Neus; Figge, Marian J; Abadias, Maribel

    2013-06-01

    The consumption of fresh-cut fruit has substantially risen over the last few years, leading to an increase in the number of outbreaks associated with fruit. Moreover, consumers are currently demanding wholesome, fresh-like, safe foods without added chemicals. As a response, the aim of this study was to determine if the naturally occurring microorganisms on fruit are "competitive with" or "antagonistic to" potentially encountered pathogens. Of the 97 and 107 isolates tested by co-inoculation with Escherichia coli O157:H7, Salmonella and Listeria innocua on fresh-cut apple and peach, respectively, and stored at 20 °C, seven showed a strong antagonistic capacity (more than 1-log unit reduction). One of the isolates, CPA-7, achieved the best reduction values (from 2.8 to 5.9-log units) and was the only isolate able to inhibit E. coli O157:H7 at refrigeration temperatures on both fruits. Therefore, CPA-7 was selected for further assays. Dose-response assays showed that CPA-7 should be present in at least the same amount as the pathogen to adequately reduce the numbers of the pathogen. From the results obtained in in vitro assays, competition seemed to be CPA-7's mode of action against E. coli O157:H7. The CPA-7 strain was identified as Pseudomonas graminis. Thus, the results support the potential use of CPA-7 as a bioprotective agent against foodborne pathogens in minimally processed fruit. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Examination of bacteriophage as a biocontrol method for salmonella on fresh-cut fruit: a model study.

    Science.gov (United States)

    Leverentz, B; Conway, W S; Alavidze, Z; Janisiewicz, W J; Fuchs, Y; Camp, M J; Chighladze, E; Sulakvelidze, A

    2001-08-01

    The preparation and distribution of fresh-cut produce is a rapidly developing industry that provides the consumer with convenient and nutritious food. However, fresh-cut fruits and vegetables may represent an increased food safety concern because of the absence or damage of peel and rind, which normally help reduce colonization of uncut produce with pathogenic bacteria. In this study, we found that Salmonella Enteritidis populations can (i) survive on fresh-cut melons and apples stored at 5 degrees C, (ii) increase up to 2 log units on fresh-cut fruits stored at 10 degrees C, and (iii) increase up to 5 log units at 20 degrees C during a storage period of 168 h. In addition, we examined the effect of lytic, Salmonella-specific phages on reducing Salmonella numbers in experimentally contaminated fresh-cut melons and apples stored at various temperatures. We found that the phage mixture reduced Salmonella populations by approximately 3.5 logs on honeydew melon slices stored at 5 and 10 degrees C and by approximately 2.5 logs on slices stored at 20 degrees C, which is greater than the maximal amount achieved using chemical sanitizers. However, the phages did not significantly reduce Salmonella populations on the apple slices at any of the three temperatures. The titer of the phage preparation remained relatively stable on melon slices, whereas on apple slices the titer decreased to nondetectable levels in 48 h at all temperatures tested. Inactivation of phages, possibly by the acidic pH of apple slices (pH 4.2 versus pH 5.8 for melon slices), may have contributed to their inability to reduce Salmonella contamination in the apple slices. Higher phage concentrations and/or the use of low-pH-tolerant phage mutants may be required to increase the efficacy of the phage treatment in reducing Salmonella contamination of fresh-cut produce with a low pH.

  13. Physicochemical changes in fresh-cut wax apple (Syzygium samarangenese [Blume] Merrill & L.M. Perry) during storage.

    Science.gov (United States)

    Supapvanich, Suriyan; Pimsaga, Jirapon; Srisujan, Panneewan

    2011-08-01

    Physicochemical changes, such as peel and flesh colours, total anthocyanin content, browning index, firmness, total soluble solid (TSS), titratable acidity (TA), sugar acid ratio (TSS/TA), antioxidant capacity, total phenolic content and ascorbic acid content, in fresh-cut Taaptimjan wax apple fruit stored at 4±2°C and 12±2°C for 7days were investigated. The skin of fresh-cut fruit stored at 4±2°C showed higher a(∗) value, chroma and total anthocyanin content and lower hue angle than those stored at 12±2°C. Lightness (L(∗) value) and whiteness index of the fresh-cut fruit flesh stored at 12±2°C showed significantly lower than those stored at 4±2°C which related to an significant increase in browning index. Firmness, total soluble solid, titratable acidity and sugar acid ratio did not significant changes during storage. Antioxidant capacity and total phenolic content increased throughout storage. Ascorbic acid content of the fresh-cut fruit stored at 4±2°C remained constant throughout storage whilst ascorbic content at 12±2°C decreased and was lower than that at 4±2°C. At 4±2°C antioxidant capacity and ascorbic acid content were higher than that stored at 12±2°C whilst there was no significant difference in total phenolic content. In conclusion, the reduction of whiteness index and the increase in browning index of fresh-cut wax apple flesh were the key factors affecting its quality and storage at 4±2°C could reduce the change in the flesh colour and maintained the peel colour and nutritional values of fresh-cut wax apple fruit during storage. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Shelf life of fresh-cut spinach as affected by chemical treatment and type of packaging film

    Directory of Open Access Journals (Sweden)

    A.M. Piagentini

    2002-12-01

    Full Text Available Fresh-cut vegetables are an important and rapidly developing class of convenience foods. Their storage life may be greatly reduced due to their high rates of respiration and transpiration and the possibility of enzymatic and microbiological deterioration. Consequently, the objective of this work was to determine the shelf life and the failure attribute that conditioned the shelf life of fresh-cut spinach treated with chemical solutions and packaged in bags with different permeabilities. The shelf life of fresh-cut vegetables was defined as the time of refrigerated storage at which any one of the sensory attributes scored below 7 or when the microbiological counts exceeded 5.10(7 CFU/g. Fresh-cut spinach was treated with citric acid and ascorbic acid solutions and packaged in mono-oriented polypropylene (OPP bags or low-density polyethylene (LDPE bags. Sensory attributes and total microbial counts were evaluated throughout refrigerated storage. Response surface methodology (RSM was used to study the simultaneous effect of chemical treatment and refrigerated storage time on sensory and microbiological quality of fresh-cut spinach. A quadratic polynomial regression model was assumed for predicting off-odor, general appearance, wilting, browning, color, and mesophilic aerobic population. Type of packaging film only influenced development of off-odor (p£0.001 and had no effect on visual sensory attributes or microbiological counts (p>0.05. Development of off-odor was the attribute that limited shelf life of fresh-cut spinach packaged in OPP bags. On the other hand, shelf life of samples packaged in LDPE bags was dependent on a decrease in general appearance or an increase in microbiological counts, depending on the chemical treatment used.

  15. Discrimination methods for biological contaminants in fresh-cut lettuce based on VNIR and NIR hyperspectral imaging

    Science.gov (United States)

    Mo, Changyeun; Kim, Giyoung; Kim, Moon S.; Lim, Jongguk; Lee, Seung Hyun; Lee, Hong-Seok; Cho, Byoung-Kwan

    2017-09-01

    The rapid detection of biological contaminants such as worms in fresh-cut vegetables is necessary to improve the efficiency of visual inspections carried out by workers. Multispectral imaging algorithms were developed using visible-near-infrared (VNIR) and near-infrared (NIR) hyperspectral imaging (HSI) techniques to detect worms in fresh-cut lettuce. The optimal wavebands that can detect worms in fresh-cut lettuce were investigated for each type of HSI using one-way ANOVA. Worm-detection imaging algorithms for VNIR and NIR imaging exhibited prediction accuracies of 97.00% (RI547/945) and 100.0% (RI1064/1176, SI1064-1176, RSI-I(1064-1173)/1064, and RSI-II(1064-1176)/(1064+1176)), respectively. The two HSI techniques revealed that spectral images with a pixel size of 1 × 1 mm or 2 × 2 mm had the best classification accuracy for worms. The results demonstrate that hyperspectral reflectance imaging techniques have the potential to detect worms in fresh-cut lettuce. Future research relating to this work will focus on a real-time sorting system for lettuce that can simultaneously detect various defects such as browning, worms, and slugs.

  16. Pathway Analysis and Metabolites Identification by Metabolomics of Etiolation Substrate from Fresh-Cut Chinese Water Chestnut (Eleocharis tuberosa

    Directory of Open Access Journals (Sweden)

    Yi-Xiao Li

    2016-12-01

    Full Text Available Fresh-cut Chinese water chestnuts (CWC turn yellow after being peeled, reducing their shelf life and commercial value. Metabolomics, the systematic study of the full complement of small molecular metabolites, was useful for clarifying the mechanism of fresh-cut CWC etiolation and developing methods to inhibit yellowing. In this study, metabolic alterations associated with etiolation at different growth stages (0 day, 2 days, 3 days, 4 days, 5 days from fresh-cut CWC were investigated using LC–MS and analyzed by pattern recognition methods (principal component analysis (PCA, partial least squares-discriminant analysis (PLS-DA, and orthogonal projection to latent structures-discriminant analysis (OPLS-DA. The metabolic pathways of the etiolation molecules were elucidated. The main metabolic pathway appears to be the conversion of phenylalanine to p-coumaroyl-CoA, followed by conversion to naringenin chalcone, to naringenin, and naringenin then following different pathways. Firstly, it can transform into apigenin and its derivatives; secondly, it can produce eriodictyol and its derivatives; and thirdly it can produce dihydrokaempferol, quercetin, and myricetin. The eriodictyol can be further transformed to luteolin, cyanidin, dihydroquercetin, dihydrotricetin, and others. This is the first reported use of metabolomics to study the metabolic pathways of the etiolation of fresh-cut CWC.

  17. Pathway Analysis and Metabolites Identification by Metabolomics of Etiolation Substrate from Fresh-Cut Chinese Water Chestnut (Eleocharis tuberosa).

    Science.gov (United States)

    Li, Yi-Xiao; Pan, Yong-Gui; He, Feng-Ping; Yuan, Meng-Qi; Li, Shang-Bin

    2016-12-01

    Fresh-cut Chinese water chestnuts (CWC) turn yellow after being peeled, reducing their shelf life and commercial value. Metabolomics, the systematic study of the full complement of small molecular metabolites, was useful for clarifying the mechanism of fresh-cut CWC etiolation and developing methods to inhibit yellowing. In this study, metabolic alterations associated with etiolation at different growth stages (0 day, 2 days, 3 days, 4 days, 5 days) from fresh-cut CWC were investigated using LC-MS and analyzed by pattern recognition methods (principal component analysis (PCA), partial least squares-discriminant analysis (PLS-DA), and orthogonal projection to latent structures-discriminant analysis (OPLS-DA)). The metabolic pathways of the etiolation molecules were elucidated. The main metabolic pathway appears to be the conversion of phenylalanine to p-coumaroyl-CoA, followed by conversion to naringenin chalcone, to naringenin, and naringenin then following different pathways. Firstly, it can transform into apigenin and its derivatives; secondly, it can produce eriodictyol and its derivatives; and thirdly it can produce dihydrokaempferol, quercetin, and myricetin. The eriodictyol can be further transformed to luteolin, cyanidin, dihydroquercetin, dihydrotricetin, and others. This is the first reported use of metabolomics to study the metabolic pathways of the etiolation of fresh-cut CWC.

  18. Formation of trichloromethane in chlorinated water and fresh-cut produce and as a result of reacting with citric acid

    Science.gov (United States)

    Chlorine (sodium hypochlorite) is commonly used by the fresh produce industry to sanitize wash water, fresh and fresh-cut fruits and vegetables. However, possible formation of harmful chlorine by-products is a concern. The objectives of this study were to compare chlorine and chlorine dioxide in t...

  19. Fresh-cut fruits and vegetables: Critical factors influencing microbiology and novel approaches to prevent microbial risks—A review

    Directory of Open Access Journals (Sweden)

    Ovais Shafiq Qadri

    2015-12-01

    Full Text Available Fruits and vegetables comprise an essential part of human diet as they are the major source of dietary nutrients of great importance. Consumption of fruits has been found to counteract many of the chronic diseases, including cancers and cardiovascular diseases. Therefore, recommendations for a balanced diet must include the consumption of fresh fruits and vegetables. Consumers in developing countries have become more concerned about the nutritional and sensory aspects as well as the safety of the food they eat due to growing health awareness. At the same time, consumer demand for convenience products is increasing and so is the demand for fresh-cut fruits and vegetables. Fresh-cut market has expanded considerably in recent years. However, quality and safety of such products are an issue of concern as these products can act as vehicles for transmitting infectious diseases. Furthermore, fresh-cut produce is more susceptible to spoilage and can facilitate rapid growth of spoilage micro-organisms as well as the micro-organisms of public health significance. Nonetheless, keeping in consideration the vast scope of fresh-cut products, this article intends to thoroughly review information about microbiology and public health risks associated with them. Discussions regarding different approaches to extend the shelf life and to minimize the risk of infection associated with their consumption are also included.

  20. Effect of mild heat-shock treatments on pink discoloration and physiological parameters in fresh-cut iceberg lettuce

    NARCIS (Netherlands)

    Paillart, M.J.M.; Otma, Els; Woltering, E.J.

    2016-01-01

    Pink discoloration is one of the major quality issues occurring in fresh-cut lettuce. Low oxygen atmosphere in modified atmosphere packaging prevents pinking but may lead to other major quality losses such as fermentation, growth of lactic acid bacteria and associated production of off-odours. The a

  1. Cold plasma as an antimicrobial intervention for fresh and fresh-cut fruits and vegetables: an ERRC research update

    Science.gov (United States)

    Contamination of fresh and fresh-cut fruits and vegetables by foodborne pathogens has prompted research at the Eastern Regional Research Center into novel interventions. Cold plasma is a nonthermal food processing technology which uses energetic, reactive gases to inactivate contaminating microbes. ...

  2. Effects of cutting and maturity on lycopene concentration of fresh-cut tomatoes during storage at different temperatures

    NARCIS (Netherlands)

    Moreira Lana, M.; Dekker, M.; Linssen, R.F.A.; Kooten, van O.

    2005-01-01

    To investigate the changes in lycopene concentration of fresh-cut tomato during storage, tomato fruits at different stages of maturity were cut into 7 mm slices and stored at temperatures varying from 2°C to 16°C. To assess the effect of cutting, intact fruit were stored in an additional experiment

  3. Comparison of Sodium Acid Sulfate and UV-C Treatment on Browning and Storage Quality of Fresh-Cut Potatoes

    Directory of Open Access Journals (Sweden)

    Yajing Xie

    2017-01-01

    Full Text Available Fresh-cut vegetables, such as potato chips, get brown quickly and can easily be infected by bacterium during storage. Sodium acid sulfate (SAS and UV-C treatments are regarded as effective methods for food preservation. In this study, the effects of SAS, UV-C treatment, and their combination on fresh-cut potatoes during storage were evaluated. Compared with the control, all of the treatments were effective in inhibiting the bacterial growth during the whole storage period. Also, both SAS and SAS + UV-C treatments significantly decreased browning and polyphenol oxidase (PPO activity and increased the firmness and malondialdehyde (MDA contents, while the UV-C treatment has no good effects on protecting such storage qualities in fresh-cut potatoes. However, when compared with SAS treatment, the combination of SAS and UV-C treatment did not promote the effect in protecting the storage abilities. Thus, it was concluded that SAS is a better treatment in extending shelf life and controlling the quality of fresh-cut potatoes during storage compared to UV-C treatment.

  4. Bacteriological survey of ready-to-eat lettuce, fresh-cut fruit, and sprouts collected from the Swiss market.

    Science.gov (United States)

    Althaus, D; Hofer, E; Corti, S; Julmi, A; Stephan, R

    2012-07-01

    The consumption of ready-to-eat fresh vegetables has increased significantly in the recent decades. So far, no data are available on the bacteriological burden and the prevalence of foodborne pathogens in ready-to-eat lettuce, fresh-cut fruit, and sprouts on the Swiss market. This study was based on investigations carried out during 2 months of the summer season in 2011. Samples of 142 salads, 64 fresh-cut fruit, and 27 sprouts were included in this study. Escherichia coli, an indicator microorganism for fecal contamination, was only found in 5 lettuce samples, with amounts ranging between 2 and 3 log CFU/g. No Salmonella spp. were detected from any of the 233 samples analyzed in this study, and a low occurrence was found for contamination with L. monocytogenes, Shiga toxin-producing E. coli, enteropathogenic E. coli, and Cronobacter. From the results of the present study, we conclude that even in a country where the use of chlorine solutions to sanitize fruits and vegetables in the fresh-cut industry is not allowed, it is possible to produce ready-to-eat lettuce, fresh-cut fruit, and sprouts with high microbiological standards. Strict maintenance of good practices of hygiene at preharvest, harvest, and postharvest levels is of central importance to ensure both public health protection and product quality.

  5. Effects of cutting and maturity on lycopene concentration of fresh-cut tomatoes during storage at different temperatures

    NARCIS (Netherlands)

    Moreira Lana, M.; Dekker, M.; Linssen, R.F.A.; Kooten, van O.

    2005-01-01

    To investigate the changes in lycopene concentration of fresh-cut tomato during storage, tomato fruits at different stages of maturity were cut into 7 mm slices and stored at temperatures varying from 2°C to 16°C. To assess the effect of cutting, intact fruit were stored in an additional experiment

  6. Effectiveness of 1-Methylcyclopropene (1-MCP Combination with Nisin-EDTA Treatment of Fresh-cut Kiwifruit for Prevention

    Directory of Open Access Journals (Sweden)

    Xiang Li

    2014-02-01

    Full Text Available A comprehensive study was made to determine the effects of 1-MCP (1 &muL L-1 pretreated combined with Nisin-EDTA (0.02 M on fresh-cut kiwifruit slices. Physico-chemical attributes of kiwifruit slices were evaluated every 3 days during storage. The fresh-cut kiwifruits pre-treated with 1-MCP, Nisin-EDTA coating and their combination showed better preservation quality and compared with the control slices during the entire storage period. 1-MCP showed an ability to relieve the pulp softening extent and inhibit total chlorophyll content decrease. Lower Polyphenol Oxidase (PPO and higher ascorbic acid were observed in Nisin-EDTA treated samples which also showed a less total bacteria count compared with the control in the end storage. Moreover, the combination of 1-MCP and Nisin-EDTA was more effective than individual treatment on maintaining the quality of fresh-cut kiwifruit, which suggested that this may be a healthy alternative method for fresh-cut kiwifruit.

  7. Influence of modified atmosphere packaging on volatile compounds and physicochemical and antioxidant attributes of fresh-cut pineapple (Ananas comosus).

    Science.gov (United States)

    Montero-Calderón, Marta; Rojas-Graü, María Alejandra; Aguiló-Aguayo, Ingrid; Soliva-Fortuny, Robert; Martín-Belloso, Olga

    2010-04-28

    The effects of modified atmosphere packaging on volatile compound content and physicochemical and antioxidant attributes of Gold cultivar fresh-cut pineapples were assessed throughout storage at 5 degrees C. Fresh-cut pineapple pieces were packed under LO (low oxygen, 12% O(2), 1% CO(2)), AIR (20.9% O(2)) and HO (high oxygen, 38% O(2)) headspace atmospheres. Methyl butanoate, methyl 2-methylbutanoate, and methyl hexanoate were the most abundant volatiles regardless of the packaging atmosphere and days of storage; whereas most odor active volatiles were methyl and ethyl 2-methylbutanoate, 2,5-dimethyl-4-methoxy-3(2H)-furanone and ethyl hexanoate. Physicochemical attributes of pineapple did not significantly vary, whereas vitamin C content and total antioxidant capacity were lower for fresh-cut pineapple in HO (488 +/- 38 mg/100 mg(fw) and 54.4 +/- 5.7%, respectively) than for LO and AIR packages. Storage life of fresh-cut pineapple was limited to 14 days by volatile compounds losses and fermentation processes.

  8. The influence of pulsed light exposure mode on quality and bioactive compounds of fresh-cut mangoes.

    Science.gov (United States)

    de Almeida Lopes, Mônica Maria; Silva, Ebenezer Oliveira; Laurent, Sandrine; Charles, Florence; Urban, Laurent; de Miranda, Maria Raquel Alcântara

    2017-07-01

    This study investigated the effect of pulsed light (PL) on the respiratory rate, quality (firmness, color and soluble solid content), bioactive compounds (ascorbate and carotenoid) and total antioxidant activity of fresh-cut "Tommy Atkins" mangoes. Fresh-cut mangoes were subjected to PL treatments: control (0P), 1 pulse (1P; 0.7 J cm(-2)), 4 successive pulses (4P; 2.80 J cm(-2)) and 1 pulse per day for 4 days (1P4D; 2.80 J cm(-2)) before storage for 7 days at 6 °C. The 1P and the 4P treatments reduced fresh mass loss during storage, while 4P-treated samples also showed a slower decline of yellow color, as shown by parameter b and overall better visual appearance. After 7 days of storage, total ascorbate content was 40% higher in the 1P4D treatment than in control, whereas total carotenoid content (0.894 mg g(-1) FM) and total antioxidant activity (144 μmol trolox 100 g(-1) FM) were the highest in the 4P-treated samples. Results suggest that PL mode of application is more important than the fluence or final dose received by fresh-cut mangoes; moreover, 4P is an effective method to preserve, or even improve quality of fresh-cut mangoes.

  9. Physicochemical, microbial and sensory quality of fresh-cut red beetroots in relation to sanization method and storage duration

    Directory of Open Access Journals (Sweden)

    Dulal Chandra

    2015-06-01

    Full Text Available Effects of sanitization and storage on fresh-cut beetroots (Beta vulgaris L. were evaluated following sanitation – peeling - cutting (SPC, peeling – sanitation – cutting (PSC and peeling – cutting – sanitation (PCS methods with (Cl, or without (TW, 100 ppm chlorine solution, then packaged in polyethylene bag and stored at 5°C for up to 14 days. Chroma values of fresh-cut beetroots significantly declined whereas whiteness index and titratable acidity values increased, however, texture and total soluble solid contents showed no significant variation. Betalain contents decreased gradually and total phenol content showed inconsistence trend. PCS-Cl treated samples accounted for higher betalains decline and received lower visual quality scores despite its lower total aerobic bacterial count. Minimum microbial population was observed in PSC-Cl methodsalong with higher levels of betalain contents. Considering pigment retention, microbial and visual qualities, beetroots sanitized with chlorine water following PSC method was the best processingway for fresh-cut beetroots and therefore, PSC-Cl treatment could commercially be used for processing of fresh-cut beetroots.

  10. Survival of Salmonella Newport on Whole and Fresh-Cut Cucumbers Treated with Lytic Bacteriophages.

    Science.gov (United States)

    Sharma, Manan; Dashiell, Gwendolyn; Handy, Eric T; East, Cheryl; Reynnells, Russell; White, Chanelle; Nyarko, Esmond; Micallef, Shirley; Hashem, Fawzy; Millner, Patricia D

    2017-04-01

    Salmonella enterica associated with consumption of cucumbers ( Cucumis sativus ) has led to foodborne outbreaks in the United States. Whole and fresh-cut cucumbers are susceptible to S. enterica contamination during growing, harvesting, and postharvest handling. The application of lytic bacteriophages specific for S. enterica was evaluated to reduce Salmonella populations on cucumbers. Unwaxed cucumbers ('Lisboa' variety, or mini-cucumbers purchased at retail) were inoculated with Salmonella Newport (5 log CFU per cucumber) and were sprayed with 3.2 mL of phosphate-buffered saline (control) or 10 log PFU/ml of SalmoFresh, a Salmonella-specific bacteriophage preparation (phage), to deliver 4.76 × 10(7) PFU/cm(2). Cucumbers were stored at 10 or 22°C for 7 days. Inoculated mini-cucumbers were sliced with a sterile knife to investigate Salmonella transfer to mesocarp, and cut pieces were stored at 4°C for 2 days. Populations (log CFU per cucumber) of Salmonella Newport on phage-treated whole cucumbers were significantly (P cucumbers (4.27 ± 0.37) on day 0. Populations on phage-treated cucumbers stored at 10°C were 1.72 ± 0.77 and 1.56 ± 0.46, which were significantly lower than those on control-treated cucumbers (3.20 ± 0.48 and 2.33 ± 0.25) on days 1 and 4, respectively. Between days 0 and 1, populations on control-treated cucumbers stored at 10 and 22°C declined by 1.07 and 2.47 log CFU per cucumber, respectively. At 22°C, Salmonella Newport populations declined by 2.37 log CFU per cucumber between days 0 and 1. Phage application to whole cucumbers before slicing did not reduce the transfer of Salmonella Newport to fresh-cut slices. Lytic phage application may be a potential intervention to reduce Salmonella populations on whole cucumbers.

  11. Estimate of respiration rate and physicochemical changes of fresh-cut apples stored under different temperatures

    Directory of Open Access Journals (Sweden)

    Cristiane Fagundes

    2013-03-01

    Full Text Available In this study, the influence of storage temperature and passive modified packaging (PMP on the respiration rate and physicochemical properties of fresh-cut Gala apples (Malus domestica B. was investigated. The samples were packed in flexible multilayer bags and stored at 2 °C, 5 °C, and 7 °C for eleven days. Respiration rate as a function of CO2 and O2 concentrations was determined using gas chromatography. The inhibition parameters were estimated using a mathematical model based on Michaelis-Menten equation. The following physicochemical properties were evaluated: total soluble solids, pH, titratable acidity, and reducing sugars. At 2 °C, the maximum respiration rate was observed after 150 hours. At 5 °C and 7 °C the maximum respiration rates were observed after 100 and 50 hours of storage, respectively. The inhibition model results obtained showed a clear effect of CO2 on O2 consumption. The soluble solids decreased, although not significantly, during storage at the three temperatures studied. Reducing sugars and titratable acidity decreased during storage and the pH increased. These results indicate that the respiration rate influenced the physicochemical properties.

  12. Effects of hydrogen peroxide treatment on thiol contents in fresh-cut asparagus (Asparagus officinalis) spears.

    Science.gov (United States)

    Demrkol, Omca

    2009-01-01

    In this work, the impact of hydrogen peroxide (H2O2) was investigated on the thiol content of asparagus. Fresh-cut asparagus was treated with H2O2 at varied oxidant concentrations and contact times. A significant decrease (alpha=0.05) was observed in N-acetylcysteine levels treated with 2.5% H2O2 for 10 min and with 5% H2O2 for 3, 5 and 10 min. Captopril and cysteine levels significantly decreased (alpha=0.05) in all and most treatment conditions, respectively. Glutathione levels only significantly decreased with 2.5% and 5% H2O2 for 10 min treatment. In order to determine whether asparagus undergoes oxidative stress, a well-known oxidative stress indicator-the glutathione/oxidized glutathione ratio-was calculated. This study showed that the common use of H2O2 as a disinfectant/sterilizer by the food industry could markedly diminish the important biothiols and develop oxidative stress in asparagus, and potentially in other vegetables as well.

  13. Colour Changes Evaluation of Freshly Cut Alder Veneers Under the Influence of Indoor Sunlight

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    Emilia Adela SALCA

    2011-03-01

    Full Text Available The paper presents an experimental study concerning the colour changes occurred on the surfaces ofblack alder veneers (Alnus glutinosa, obtained from a freshly cut (not treated log, after their exposure tosunlight and darkness, for 1 and 3 months, under indoor conditions.A Chroma Meter Konika Minolta CR-410 device was used for colour measurement.The colorimetric coordinates were recorded before and after the exposure, according to ISO 7724-2.The results highlight a significant decrease of colour lightness, right after the first month of sunlight exposure.The a* and b* colour coordinates showed an increasing tendency with increasing exposure time, whichsignifies a colour darkening under sunlight radiation that penetrates the window glass. Colour differenceswere noticed right after the first month of sunlight exposure, while under darkness conditions, a relativecolour constancy was noticed, the colour changes being less pronounced, but yet perceptible by the humaneye.The study results complete the colorimetric database of veneers used in furniture industry, but theyalso contribute to the rehabilitation of black alder as a wood species with a real potential of use in furnitureindustry.

  14. High hydrostatic pressure as a method to preserve fresh-cut Hachiya persimmons: A structural approach.

    Science.gov (United States)

    Vázquez-Gutiérrez, José Luis; Quiles, Amparo; Vonasek, Erica; Jernstedt, Judith A; Hernando, Isabel; Nitin, Nitin; Barrett, Diane M

    2016-12-01

    The "Hachiya" persimmon is the most common astringent cultivar grown in California and it is rich in tannins and carotenoids. Changes in the microstructure and some physicochemical properties during high hydrostatic pressure processing (200-400 MPa, 3 min, 25 ℃) and subsequent refrigerated storage were analyzed in this study in order to evaluate the suitability of this non-thermal technology for preservation of fresh-cut Hachiya persimmons. The effects of high-hydrostatic pressure treatment on the integrity and location of carotenoids and tannins during storage were also analyzed. Significant changes, in particular diffusion of soluble compounds which were released as a result of cell wall and membrane damage, were followed using confocal microscopy. The high-hydrostatic pressure process also induced changes in physicochemical properties, e.g. electrolyte leakage, texture, total soluble solids, pH and color, which were a function of the amount of applied hydrostatic pressure and may affect the consumer acceptance of the product. Nevertheless, the results indicate that the application of 200 MPa could be a suitable preservation treatment for Hachiya persimmon. This treatment seems to improve carotenoid extractability and tannin polymerization, which could improve functionality and remove astringency of the fruit, respectively. © The Author(s) 2016.

  15. Effectiveness of a bacteriophage in reducing Listeria monocytogenes on fresh-cut fruits and fruit juices.

    Science.gov (United States)

    Oliveira, M; Viñas, I; Colàs, P; Anguera, M; Usall, J; Abadias, M

    2014-04-01

    Listeria monocytogenes is a serious foodborne pathogen and new strategies to control it in food are needed. Among them, bacteriophages hold attributes that appear to be attractive. The objective of this study was to investigate the efficacy of the bacteriophage Listex P100 to control L. monocytogenes growth on melon, pear and apple products (juices and slices) stored at 10 °C. L. monocytogenes grew well in untreated fruit slices. In juices, the pathogen grew in untreated melon, survived in untreated pear and decreased in untreated apple. Phage treatment was more effective on melon followed by pear, but no effect on apple products was observed. Reductions of about 1.50 and 1.00 log cfu plug(-1) for melon and pear slices were found, respectively. In juices, higher reductions were obtained in melon (8.00 log cfu mL(-1)) followed by pear (2.10 log cfu mL(-1)) after 8 days of storage. L. monocytogenes in apple juice was unaffected by phage treatment in which the phage decreased to almost undetectable numbers. These results highlight that Listex P100 could avoid pathogen growth on fresh-cut and in fruit juices with high pH during storage at 10 °C. The combination with other technologies may be required to improve the phage application on high acidity fruits. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Apple Puree-Alginate Edible Coating as Carrier of Antimicrobial Agents to Prolong Shelf-Life of Fresh-Cut Apples

    Science.gov (United States)

    Edible coatings with antimicrobial agents can extend the shelf-life of fresh-cut fruit. The effect of lemongrass, oregano oil and vanillin incorporated in apple puree-alginate edible coatings, on the shelf-life of fresh-cut Fuji apples, was investigated. Coated apples were packed in air-filled pol...

  17. Behavior of Salmonella spp. and natural microbiota on fresh-cut dragon fruits at different storage temperatures.

    Science.gov (United States)

    Sim, Hui Li; Hong, Yoon-Ki; Yoon, Won Byong; Yuk, Hyun-Gyun

    2013-01-01

    The aim of this study was to determine survival or growth of unadapted, acid-adapted and cold-stressed Salmonella spp., and natural microbiota on fresh-cut dragon fruits at different storage temperatures. Dragon fruits were sliced and spot inoculated with five-strain cocktail of Salmonella spp. at two inoculum levels (2.5 or 5.5 log CFU/g). Inoculated fruits were stored at 28°C for 48h and at 4°C and 12°C for 96 h. Salmonella population significantly increased by 2.4 to 3.0 log CFU/g at low inoculum level, whereas the numbers increased by 0.4 to 0.7 log CFU/g at the high inoculum level on fruits held at 28°C for 48h. Only unadapted and acid-adapted cells grew with 0.7 to 0.9log increase at the low inoculum level at 12°C for 96h. No significant growth was observed at both inoculum levels during storage at 4°C. Overall, acid, starved and cold adaptation of Salmonella spp. did not show significant difference in survival or growth on fresh-cut dragon fruits during storage compared to unadapted control cells. For natural microbiota on the fruit, mesophilic bacterial counts reached to 5-log CFU/g at 28 and 12°C by 9.9 and 52.9h. Similar with Salmonella spp. there was no growth of natural microbiota at 4°C. These results showed that Salmonella spp. could grow on fresh-cut dragon fruits under inappropriate storage conditions, indicating that fresh-cut dragon fruits could be a potential vehicle for salmonellosis. Thus, this study suggests that fresh-cut dragon fruits should be stored at 4°C to ensure the safety as well as to extend the shelf life of fresh-cut dragon fruits. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Processamento mínimo de mamão 'formosa' Fresh cut of 'formosa' papaya

    Directory of Open Access Journals (Sweden)

    Gustavo Henrique de Almeida TEIXEIRA

    2001-01-01

    Full Text Available Este trabalho foi conduzido para verificar o efeito do tamanho do corte, 2,5 x 2,5cm (corte 1 e 2,5 x 5,0cm (corte 2, e da temperatura de armazenamento (3, 6 e 9ºC, na velocidade da modificação da atmosfera ambiente e nas características químicas de mamões do grupo `Formosa' minimamente processados e embalados em copos plásticos (500ml. A concentração de CO2 no interior destes copos aumentou 2 a 3 vezes, durante as primeiras 6 horas após o corte, para depois diminuir e se estabilizar. Esta concentração aumentou com o aumento da temperatura de armazenamento. A umidade dos pedaços diminuiu consideravelmente nos dois primeiros dias, e a temperatura que melhor conservou a umidade foi a de 6ºC. A acidez total titulável foi menor no corte 2, com as maiores reduções a 6 e 9oC. Os teores de sólidos solúveis totais não variaram entre os tratamentos, e os cuidados higiênicos adotados durante o processamento permitiram a obtenção de produtos com baixa contagem microbiana, 10³UFC.g-1 nos pedaços armazenados a 9ºC após sete dias, e com boa manutenção da qualidade sensorial das mesmas. Estes resultados permitem indicar o mamão `Formosa' para a produção de produtos minimamente processados, na forma de pedaços, com conservação refrigerada (3 e 6ºC por um período de 7 dias.This work was undertaken to verify the effect of cutting size, 2.5 x 2.5cm (chunk 1, 2.5 x 5.0cm (chunk 2, and storage temperatures (3, 6 and 9ºC, on atmosphere modification rate and chemical characteristics of `Formosa' fresh-cut papaya packed in plastic cups (500 ml. The CO2 concentration into theses cups increased fron two to three fold during first 6 hours after cutting, then it decreased and stabilized. This concentration increased with the storage temperature increasing. The chunks's moisture remarkably decreased in the first 2 days, and the temperature which best sustained the moisture was 6ºC. The titratable total acidity was lower in chunk 2

  19. In vitro rumen simulated (RUSITEC) metabolism of freshly cut or wilted grasses with contrasting polyphenol oxidase activities

    OpenAIRE

    2011-01-01

    The study investigated in vitro simulated rumen metabolism of freshly cut and wilted cocksfoot [Dactylis glomerata; high polyphenol oxidase (PPO)] and tall fescue (Festuca arundinacea; low PPO). A 16-vessel RUSITEC was used with the four treatment combinations: cocksfoot wilted (C(w)); cocksfoot fresh (C(f)); tall fescue wilted (TF(w)) and tall fescue fresh (TF(f)). Rumen liquor was collected from four fistulated dairy cows maintained on permanent pasture. The experiment ran for 12 d with sam...

  20. The effectiveness of ozone and acidulant treatments in extending the refrigerated shelf life of fresh-cut potatoes.

    Science.gov (United States)

    Calder, Beth L; Skonberg, Denise I; Davis-Dentici, Katherine; Hughes, Brianna H; Bolton, Jason C

    2011-10-01

    The objective of the study was to determine the effectiveness of acidulant dip treatments (with or without aqueous ozone) to reduce enzymatic browning and to extend the shelf life of fresh-cut potato slices during refrigerated storage (4 °C) for 28 d. Potato slices subjected to aqueous ozone (2 ppm) had significantly (P≤ 0.05) higher L-values and lower a-values, but ozone did not appear to have any effect on aerobic plate counts (APCs) or polyphenol oxidase (PPO) activity. NatureSeal (NS) and sodium acid sulfate (SAS) were the most effective acidulant treatments in reducing browning (significantly [P≤ 0.05] higher L-values, lower a-values, and browning index values) regardless of ozone treatment. NS and SAS also had lower PPO activity compared to other treatments on days 0 and 28, and significantly (P≤ 0.05) lower APCs (≤2.00 log CFU/g) over refrigerated storage. Therefore, the SAS treatment was comparable to NS, a commercially available product, and showed promise as an effective antibrowning dip to reduce browning and spoilage in fresh-cut potato products. Practical Application:  A 1% SAS dip treatment which included 1% citric and 1% ascorbic acid was found to be an effective antibrowning dip for fresh-cut potatoes along with NatureSeal®'s PS-10, compared to other treatments. They were both effective in maintaining low microbial counts over refrigerated storage. Additionally, aqueous ozone washes (2 ppm) showed significant benefits to reduce browning; however, ozone did not affect microbial counts or PPO enzyme activity. Therefore, the SAS treatment could have potential use in the fruit and vegetable industry to reduce browning and spoilage in fresh-cut potato products.

  1. Modelling sensorial and nutritional changes to better define quality and shelf life of fresh-cut melons

    Directory of Open Access Journals (Sweden)

    Maria Luisa Amodio

    2013-06-01

    Full Text Available The shelf life of fresh-cut produce is mostly determined by evaluating the external appearance since this is the major factor affecting consumer choice at the moment of purchase. The aim of this study was to investigate the degradation kinetics of the major quality attributes in order to better define the shelf life of fresh-cut melons. Melon pieces were stored for eight days in air at 5°C. Sensorial and physical attributes including colour, external appearance, aroma, translucency, firmness, and chemical constituents, such as soluble solids, fructose, vitamin C, and phenolic content, along with antioxidant activity were monitored. Attributes showing significant changes over time were used to test conventional kinetic models of zero and first order, and Weibullian models. The Weibullian model was the most accurate to describe changes in appearance score, translucency, aroma, firmness and vitamin C (with a regression coefficient always higher than 0.956, while the other parameters could not be predicted with such accuracy by any of the tested models. Vitamin C showed the lowest kinetic rate among the model parameters, even though at the limit of marketability (appearance score 3, estimated at five days, a loss of 37% of its initial content was observed compared to the fresh-cut product, indicating a much lower nutritional value. After five days, the aroma score was already 2.2, suggesting that this quality attribute, together with the vitamin C content, should be taken into account when assessing shelf life of fresh-cut melons. In addition, logistical models were used to fit the percentage of rejected samples on the basis of non-marketability and non-edibility (appearance score <3 and <2, respectively. For both parameters, correlations higher than 0.999 were found at P<0.0001; for each mean score this model helps to understand the distribution of the samples among marketable, nonmarketable, and non-edible products.

  2. Evaluation of Combined Disinfection Methods for Reducing Escherichia coli O157:H7 Population on Fresh-Cut Vegetables

    Directory of Open Access Journals (Sweden)

    Eva Petri

    2015-07-01

    Full Text Available Most current disinfection strategies for fresh-cut industry are focused on the use of different chemical agents; however, very little has been reported on the effectiveness of the hurdle technology. The effect of combined decontamination methods based on the use of different sanitizers (peroxyacetic acid and chlorine dioxide and the application of pressure (vacuum/positive pressure on the inactivation of the foodborne pathogen E. coli O157:H7 on fresh-cut lettuce (Lactuca sativa and carrots (Daucus carota was studied. Fresh produce, inoculated with E. coli O157:H7, was immersed (4 °C, 2 min in tap water (W, chlorine water (CW, chlorine dioxide (ClO2: 2 mg/L and peroxyacetic acid (PAA: 100 mg/L in combination with: (a vacuum (V: 10 mbar or (b positive pressure application (P: 3 bar. The product quality and antimicrobial effects of the treatment on bacterial counts were determined both in process washing water and on fresh-cut produce. Evidence obtained in this study, suggests that the use of combined methods (P/V + sanitizers results in a reduction on the microorganism population on produce similar to that found at atmospheric pressure. Moreover, the application of physical methods led to a significant detrimental effect on the visual quality of lettuce regardless of the solution used. Concerning the process water, PAA proved to be an effective alternative to chlorine for the avoidance of cross-contamination.

  3. Effect of supercritical carbon dioxide pasteurization on natural microbiota, texture, and microstructure of fresh-cut coconut.

    Science.gov (United States)

    Ferrentino, Giovanna; Balzan, Sara; Dorigato, Andrea; Pegoretti, Alessandro; Spilimbergo, Sara

    2012-05-01

    The objective of the present study was the evaluation of the effectiveness of supercritical carbon dioxide (SC-CO(2)) as a nonthermal technology for the pasteurization of fresh-cut coconut, as an example of ready-to-eat and minimally processed food. First, the inactivation kinetics of microbiota on coconut were determined using SC-CO(2) treatments (pressures at 8 and 12 MPa, temperatures from 24 to 45 °C, treatment times from 5 to 60 min). Second, the effects of SC-CO(2) on the hardness and microstructure of fresh-cut coconut processed at the optimal conditions for microbial reduction were investigated. SC-CO(2) treatment of 15 min at 45 °C and 12 MPa induced 4 log CFU/g reductions of mesophilic microorganisms, lactic acid bacteria, total coliforms, and yeasts and molds. The hardness of coconut was not affected by the treatment but the samples developed an irregular and disorderly microstructure. Results suggested the potential of SC-CO(2) in preserving fresh-cut fruits and ready-to-eat products. © 2012 Institute of Food Technologists®

  4. Cassava starch coating and citric acid to preserve quality parameters of fresh-cut "Tommy Atkins" mango.

    Science.gov (United States)

    Chiumarelli, Marcela; Pereira, Leila M; Ferrari, Cristhiane C; Sarantópoulos, Claire I G L; Hubinger, Miriam D

    2010-06-01

    Combination of citric acid dipping (5 g/L) and cassava starch coating (10 g/L), with and without glycerol (10 g/L), was studied to verify the effectiveness of these treatments to inhibit enzymatic browning, to reduce respiration rate, and to preserve quality parameters of "Tommy Atkins" fresh-cut mangoes during storage at 5 degrees C. Color characteristics (L and C), mechanical properties (stress at failure), weight loss, beta-carotene content, sensory acceptance, and microbial growth of fruits were evaluated during 15 d. The respiration rate of fruit subjected to the treatments was also analyzed. Nontreated fresh-cut mango was used as a control sample. Cassava starch edible coatings and citric acid dipping promoted a decrease in respiration rate of mango slices, with values up to 41% lower than the control fruit. This treatment also promoted better preservation of texture and color characteristics of mangoes and delayed carotenoid formation and browning reactions during storage. Moreover, the treated fruit showed great sensory acceptance by consumers throughout the whole storage period. However, the use of glycerol in the coating formulation was not efficient in the maintenance of quality parameters of fresh-cut mangoes, promoting a higher weight loss of samples, impairing fruit texture characteristics, increasing carotenogenesis, and favoring microbial growth during storage.

  5. Color, flavor, texture, and nutritional quality of fresh-cut fruits and vegetables: desirable levels, instrumental and sensory measurement, and the effects of processing.

    Science.gov (United States)

    Barrett, Diane M; Beaulieu, John C; Shewfelt, Rob

    2010-05-01

    The color, flavor, texture, and the nutritional value of fresh-cut fruit and vegetable products are factors critical to consumer acceptance and the success of these products. In this chapter, desirable and undesirable quality attributes of fresh-cut fruit and vegetable products are reviewed. Both instrumental and sensory measurements for determining these critical quality attributes are discussed. The advantages and disadvantages of sensory and instrumental quality measurements are described. A review of typical unit operations involved in the production of fresh-cut products is presented. The effects of fresh-cut processing techniques and treatments on sensory quality, including the appearance, texture, flavor (taste and aroma) of vegetables, and fruits are detailed.

  6. Utilization of physicochemical variables developed from changes in sensory attributes and consumer acceptability to predict the shelf life of fresh-cut mango fruit

    National Research Council Canada - National Science Library

    Salinas-Hernández, Rosa María; González-Aguilar, Gustavo A; Tiznado-Hernández, Martín Ernesto

    2015-01-01

    ...*, chroma and hue angle), total soluble solids (TSS), firmness (F), pH, acidity, and the sensory attributes of appearance, brightness, browning, odor, flavor, texture, color, acidity and sweetness were evaluated in fresh cut mangoes (FCM...

  7. Effects of Organic Acids Treatments with or without Ultra-Sonic Treatment on Increasing the Shelf Life of Fresh Cut Kiwifruit

    Directory of Open Access Journals (Sweden)

    A. Mansoory

    2016-02-01

    Full Text Available The market sales of ready to use fresh cut fruits have grown rapidly in recent decades. Kiwi fruit is an important fruit that its marketing as fresh cut has increased in recent years. The main limiting factors in shelf life of fresh cut fruits are microbial spoilage, drastic softening and browning. In this study, the effects of oxalic and citric acids, both at 0, 2, 4 and 6 mM concentrations, with or without ultra-sonic treatment were investigated on the increasing the shelf life of fresh cut kiwi fruit. After treatments, the fresh slices were stored at 2°C for 7 or 14 days and assessed for several traits and analyzed. Results showed that, oxalic and citric acid treated slices, in comparison to the control, had greater marketability, as well as higher flesh firmness, titrable acidity, ascorbic acid content, total phenol content and antioxidant capacity and smaller bacterial forming colony unit (CFU. Among the treatments, 2, 4 and 6 mM oxalic acid and 6 mM citric acid treatments were found more appropriate than the reaming treatments. Application of ultra-sonic treatment, despite the reduction of microbial load and maintaining antioxidant capacity, had no effects on marketability of fresh cut kiwi fruit. Hence, application of organic acid treatments as dipping can be used to increase the shelf life of fresh cut kiwi fruit.

  8. Determinação da microflora em rabanetes minimamente processados Determination of microorganisms in fresh-cut radishes

    Directory of Open Access Journals (Sweden)

    Juan S del Aguila

    2006-03-01

    Full Text Available O presente trabalho visou comparar dois tratamentos de sanitização e identificar alguns microorganismos associados ao processamento mínimo da raiz de rabanete. Foram avaliados dois métodos de sanitização: 1 sanitização convencional: raízes de rabanete minimamente processadas em retalhos receberam uma única sanitização, por 3 minutos em uma solução de 200 mg L-1 de cloro ativo; 2 sanitização adicional: raízes de rabanete minimamente processadas foram inicialmente sanitizadas na "área suja", numa solução de 200 mg L-1 de cloro ativo por 10 minutos, para posteriormente ingressar na "área limpa", e receber uma segunda sanitização nas mesmas condições do tratamento 1. As análises microbiológicas foram realizadas em duas fases: a após o corte; e b no 10º dia de armazenamento a 5ºC (±1ºC e 90% (±5% UR. Para cada dia de análise foram utilizadas 4 repetições de 130 g de raiz de rabanete minimamente processada. As contagens de bactérias psicrotróficas no tratamento 2 mantiveram-se dentro dos limites aceitáveis. No tratamento 1 obteve-se, no 10º dia de armazenamento, 5,8 x 10(6 UFC g-1, equivalente ao limite máximo recomendado. Não foi detectada presença de coliformes e Salmonella em ambos os tratamentos. Conclui-se que uma primeira sanitização, com 200 mg L-1 de cloro ativo por 10 minutos, é recomendável para a obtenção de raízes de rabanete minimamente processadas de qualidade até o 10º dia de armazenamento a 5ºC, permitindo a comercialização do produto dentro do estabelecido pela legislação vigente de alimentos frescos.The present work was carried out to compare two sanitation treatments and to identify some microorganisms associated with fresh cut radishes. Two sanitation methods were evaluated: 1 conventional sanitation: fresh cut radishes received a single sanitation, for 3 minutes in a solution of 200 mg L-1 of active chlorine; 2 additional sanitation: fresh cut radishes were sanitated

  9. Effects of cutting and maturity on lycopene concentration of fresh-cut tomatoes during storage at different temperatures

    OpenAIRE

    Moreira Lana, M.; Dekker, M.; Linssen, R.F.A.; Kooten, van, G.C.

    2005-01-01

    To investigate the changes in lycopene concentration of fresh-cut tomato during storage, tomato fruits at different stages of maturity were cut into 7 mm slices and stored at temperatures varying from 2°C to 16°C. To assess the effect of cutting, intact fruit were stored in an additional experiment at 5°C. Cutting did not change the accumulation of lycopene in fruit stored at 5°C, compared to intact fruit. The lycopene concentration of the tomato slices stored at different temperatures showed...

  10. Effect of Calcium Lactate and Heat-Shock on Texture in Fresh-Cut Lettuce During Storage

    OpenAIRE

    Martin-Diana, Ana Belen; Rico, Daniel; Frias, Jesus Maria; Henehan, Gary; Mulcahy, Jemina; Barat, J.; Barry-Ryan, Catherine

    2006-01-01

    Textural and microstructural changes in fresh-cut lettuce were analysed over 12 days storage. The vegetable was treated with 120 ppm chlorine and with 15 g/L calcium lactate at room temperature (18–20 °C) and at 50 °C (heat-shock). Texturometer analysis showed that samples washed with calcium lactate had significantly (p > 0.05) higher crispness values than samples washed with chlorine. However the use of 50 °C treatment (heat-shock) gave better textural properties at the end of storage and s...

  11. Effect of Ozone and Calcium Lactate Treaments on Browning and Textured Properties of Fresh-Cut Lettuce

    OpenAIRE

    Rico, Daniel; Martin-Diana, Ana Belen; Henehan, Gary; Frias, Jesus Maria; Barry-Ryan, Catherine

    2006-01-01

    The effects of three treatments, 1 mg L−1 ozone at 18–20 °C, 15 g L−1 calcium lactate (CLac) at 50 °C and a combination thereof, were compared on fresh-cut lettuce over 10 days of refrigerated storage. Respiration rate, browning and texture were examined as main quality indicators. The use of ozone produced a significantly (P < 0.05) higher oxygen decline than the use of CLac (from day 3 to day 10). At the end of storage, CLac (alone or combined with ozone) samples had higher oxygen content (...

  12. Nutritional and sensory quality during refrigerated storage of fresh-cut mints (Mentha×piperita and M. spicata).

    Science.gov (United States)

    Curutchet, Ana; Dellacassa, Eduardo; Ringuelet, Jorge A; Chaves, Alicia R; Viña, Sonia Z

    2014-01-15

    The effect of storage time on quality attributes of refrigerated fresh-cut mints (Mentha×piperita and M. spicata) was studied. Atmosphere composition, respiratory activity, weight loss, surface colour, total chlorophyll, carotenoids, browning potential, total phenols, flavonoids, radical-scavenging activity, ascorbic acid and essential oil yield and composition were analysed. Respiratory activity of peppermint and spearmint samples diminished moderately (42% and 28%, respectively) after 21days at 0°C. A slight modification of the internal atmosphere was achieved. Surface colour, chlorophyll, carotenoid and antioxidant compounds remained almost constant. The yield of essential oil did not change or it showed an apparent increase after 21days at 0°C, depending on plant growth stage. The characteristic flavour components of peppermint (menthone and menthol) increased, while the contents of the main constituents of spearmint essential oil showed minor variations after storage. The conditions assayed for packaging and storing fresh-cut mints were adequate to achieve a relatively long shelf life and they retained their antioxidant properties. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. A New On-Line Detecting Apparatus of the Residual Chlorine in Disinfectant for Fresh-Cut Vegetables

    Science.gov (United States)

    Hu, Chao; Su, Shu-Qiang; Li, Bao-Guo; Liu, Meng-Fang

    With the fast development of modern food and beverage industry, fresh-cut vegetables have wider application than before. During the process of sterilization in fresh-cut vegetables, the concentration of chloric disinfectant is usually so high that the common sensor can't be used directly on the product line. In order to solve this problem, we have invented a new detecting apparatus which could detect high concentration of chloric disinfectant directly. In this paper, the working principle, main monitor indicators, application and technical creations of the on-line apparatus have been discussed, and we also carried on the experimental analysis for its performance. The actual demands in factory could be met when the detecting flux is 2L/min, the dilution ratio is 15 and input amount of the disinfectant is 200ml per time, the max of the detecting deviation achieves ±4.8ppm(mg/L). The main detecting range of residual chlorine is 0~300ppm.

  14. Disinfection potential of ozone, ultraviolet-C and their combination in wash water for the fresh-cut vegetable industry.

    Science.gov (United States)

    Selma, María V; Allende, Ana; López-Gálvez, Francisco; Conesa, María A; Gil, María I

    2008-09-01

    The purpose of this research was to investigate the disinfection efficacy of ozone (O(3)) and UV-C illumination (UV), and their combination (O(3)-UV) for reducing microbial flora of fresh-cut onion, escarole, carrot, and spinach wash waters collected from the industry. Furthermore, the influence of water physicochemical parameters on the decontamination efficacy and the effect of these technologies on physicochemical quality of wash water were analyzed. O(3), UV, and O(3)-UV were effective disinfection treatments on vegetable wash water, with a maximum microbial reduction of 6.6 log CFU mL(-1) after 60 min treatment with O(3)-UV. However, maximum total microbial reductions achieved by UV and O(3) treatments after 60 min were 4.0 and 5.9 log CFU mL(-1), lower than by O(3)-UV treatment. Furthermore, turbidity of wash water was reduced significantly by O(3) and O(3)-UV treatments, while UV treatment did not affect the physicochemical quality of the water. Conclusions derived from this study illustrate that O(3) and O(3)-UV are alternatives to other sanitizers used in the fresh-cut washing processes. The use of these technologies would allow less frequent changing of spent water and the use of much lower sanitizer doses. Nevertheless, in specific applications such as carrot wash water, where levels of undesirable microbial and chemical constituents are lower than other vegetable wash water, UV treatment could be an appropriate treatment considering cost-effectiveness criteria.

  15. Recent advances in modified atmosphere packaging and edible coatings to maintain quality of fresh-cut fruits and vegetables.

    Science.gov (United States)

    Ghidelli, Christian; Pérez-Gago, María B

    2016-07-28

    Processing of fruits and vegetables generates physiological stresses in the still living cut tissue, leading to quality deterioration and shorter shelf-life as compared with fresh intact produces. Several strategies can be implemented with the aim to reduce the rate of deterioration of fresh-cut commodities. Such strategies include low temperature maintenance from harvest to retail and the application of physical and chemical treatments such as modified atmosphere packaging (MAP) with low O2 and high CO2 levels and antioxidant dips. Other technologies such as edible coatings with natural additives, new generation of coatings using nanotechnological solutions such as nanoparticles, nanoencapsulation, and multilayered systems, and non-conventional atmospheres such as the use of pressurized inert/noble gases and high levels of O2 have gained a lot of interest as a possibility to extend the shelf life of minimally processed fruits and vegetables. However, the high perishability of these products challenges in many cases their marketability by not achieving sufficient shelf life to survive the distribution system, requiring the combination of treatments to assure safety and quality. This review reports the recent advances in the use of MAP, edible coatings, and the combined effect of both technologies to extend the shelf life of fresh-cut fruits and vegetables.

  16. Physicochemical, sensory, and nutritional quality of fresh-cut "Rojo Brillante" persimmon affected by maturity stage and antibrowning agents.

    Science.gov (United States)

    Sanchís, Elena; Mateos, Milagros; Pérez-Gago, María B

    2016-10-01

    To prevent enzymatic browning of fresh-cut 'Rojo Brillante' persimmon, different combinations of ascorbic acid (AA) and citric acid (CA) with calcium chloride (CaCl2) were tested in fruit harvested at two maturity stages (MS1 and MS2). Color, firmness, sensory quality, total vitamin C, radical scavenging activity, total phenolic content, and carotenoids were evaluated over nine days of storage at 5 ℃. Antibrowning dips reduced enzymatic browning if compared with the control samples. Selecting fruits with good firmness and the addition of 10 g/l CaCl2 help prevent loss of firmness of fresh-cut "Rojo Brillante" persimmons treated with acidic solutions as antibrowning agents to control enzymatic browning. The limit of marketability of the persimmon fruit processed at MS1 was significantly reduced by the burst of the disorder known as "flesh browning," and only the samples treated with 10 g/l CA + 10 g/l CaCl2 maintained a limit of marketability close to seven days. At MS2, all the antibrowning solutions allowed a limit of marketability of seven storage days at 5 ℃. Nutritional quality was not affected by either antibrowning dips or cutting processes, but MS at harvest was. © The Author(s) 2016.

  17. Effects of clove essential oil and eugenol on quality and browning control of fresh-cut lettuce.

    Science.gov (United States)

    Chen, Xiangning; Ren, Lupei; Li, Menglin; Qian, Jia; Fan, Junfeng; Du, Bin

    2017-01-01

    This study confirmed the inhibitory effects of clove essential oil (CEO) and eugenol (EUG) on the browning and relevant enzymes of fresh-cut lettuce, and examined associated mechanisms by inhibition kinetics and computational docking analysis. Fresh-cut lettuce was treated with 0.05% CEO and 0.05% EUG solutions, resulting in inhibition of the deterioration of texture quality and browning of the lettuce surface and interior. Compared with the controls, CEO and EUG significantly inhibited the activities of phenylalanine ammonia lyase (PAL), polyphenol oxidase (PPO), and peroxidase (POD, all p<0.05). EUG suppressed PAL, PPO, and POD in vitro in a dose-dependent manner, with IC50 values of 5.4±0.9, 29.5±3.5, and 61.9±6.7mM, respectively. The binding and inhibition effects of EUG on PAL, PPO, and POD, determined by inhibition kinetics and computational docking analysis, established EUG as a competitive inhibitor of these browning-relevant enzymes.

  18. Enhancing safety and aroma appealing of fresh-cut fruits and vegetables using the antimicrobial and aromatic power of essential oils.

    Science.gov (United States)

    Ayala-Zavala, J Fernando; González-Aguilar, Gustavo A; del-Toro-Sánchez, L

    2009-09-01

    Microbial and aroma attributes are within the most decisive factors limiting safety and sensory appealing of fresh-cut fruits and vegetables. Alternatively, several plant essential oils (EOs) are constituted of several volatile active compounds and most of them present antimicrobial potential and had different aroma profile. Considering these premises, this hypothesis article states that safety and aroma appealing of fresh-cut produce could be improved with EO treatment. EOs could prevent fresh-cut fruit decay; however, their volatile constituents could be sorbed by the produce, and according to the aroma notes of the antimicrobial oil, sensorial appealing of odor, and flavor of the treated produce might be affected positively or negatively. Specifically, garlic oil is a natural antimicrobial constituted by sulfur compounds, which are responsible for its odor and antimicrobial properties. Besides, fresh-cut tomato is a highly perishable product that needs antimicrobial agents to preserve its quality and safety for a longer period of time. From the sensorial point of view, aroma combination of garlic and tomato is a common seasoning practice in Europe and America and well accepted by consumers. Once the right combination of flavors between the EOs and the fresh-cut produce has been selected, safety and quality of the treated fruit could be improved by adding antimicrobial protection and extra aroma. Therefore, other combinations between EOs and fresh-cut produce are discussed. This approximation could reinforce the trends of natural food preservation, accomplishing the demands of the increasing sector of consumers demanding tasty and convenient fresh-cut produce, containing only natural ingredients.

  19. Muskmelon seed priming in relation to seed vigor

    OpenAIRE

    Nascimento Warley Marcos; Aragão Fernando Antônio Souza de

    2004-01-01

    A number of important factors may affect seed priming response, including seed quality. Effects of seed vigor on seed priming response were investigated using seed lots of two muskmelon (Cucumis melo L.) cultivars. Seeds of muskmelon, cvs. Mission and Top Net SR were artificially aged at 43°C for 0, 20 and 40 hours. Seeds were primed for six days in darkness at 25°C in KNO3 (0.35 mol L-1) aerated solution. Aged seeds germinated poorly at 17°C. Priming increased germination rate at 17 and 25°C...

  20. Quality index, consumer acceptability, bioactive compounds, and antioxidant activity of fresh-cut "ataulfo" mangoes (mangifera indica L.) as affected by low-temperature storage.

    Science.gov (United States)

    Robles-Sánchez, R M; Islas-Osuna, M A; Astiazarán-García, H; Vázquez-Ortiz, F A; Martín-Belloso, O; Gorinstein, S; González-Aguilar, G A

    2009-04-01

    To measure bioactive compound losses due to minimal processing, mature green fresh-cut mangoes (Mangifera indica L.) cv. "Ataulfo" were subjected to an antioxidant treatment and stored at 5 degrees C during 15 d. Quality index, total phenols, flavonoids, beta-carotene, ascorbic acid, vitamin E, and antioxidant activity were measured during the storage period of fruits. Antioxidant capacity was estimated using ORAC(FL), TEAC, and DPPH assays. The dipping treatments with ascorbic acid (AA) + citric acid (CA) + CaCl2 affected positively quality delaying deterioration of fresh-cut mango as compared with whole fruit. However, dipping treatment affected the consumer preferences of fresh-cut mangoes. The highest vitamin C, beta-carotene, and vitamin E losses were observed after 10 d, being similar in whole and fresh-cut mangoes. The antioxidant activity was not significantly affected by storage time. We conclude that fresh-cut mangoes retained their bioactive compound content during storage and their antioxidant and nutritional properties make them a good source of these compounds.

  1. A single method for recovery and concentration of enteric viruses and bacteria from fresh-cut vegetables.

    Science.gov (United States)

    Sánchez, G; Elizaquível, P; Aznar, R

    2012-01-03

    Fresh-cut vegetables are prone to be contaminated with foodborne pathogens during growth, harvest, transport and further processing and handling. As most of these products are generally eaten raw or mildly treated, there is an increase in the number of outbreaks caused by viruses and bacteria associated with fresh vegetables. Foodborne pathogens are usually present at very low levels and have to be concentrated (i.e. viruses) or enriched (i.e. bacteria) to enhance their detection. With this aim, a rapid concentration method has been developed for the simultaneous recovery of hepatitis A virus (HAV), norovirus (NV), murine norovirus (MNV) as a surrogate for NV, Escherichia coli O157:H7, Listeria monocytogenes and Salmonella enterica. Initial experiments focused on evaluating the elution conditions suitable for virus release from vegetables. Finally, elution with buffered peptone water (BPW), using a Pulsifier, and concentration by polyethylene glycol (PEG) precipitation were the methods selected for the elution and concentration of both, enteric viruses and bacteria, from three different types of fresh-cut vegetables by quantitative PCR (qPCR) using specific primers. The average recoveries from inoculated parsley, spinach and salad, were ca. 9.2%, 43.5%, and 20.7% for NV, MNV, and HAV, respectively. Detection limits were 132 RT-PCR units (PCRU), 1.5 50% tissue culture infectious dose (TCID₅₀), and 6.6 TCID₅₀ for NV, MNV, and HAV, respectively. This protocol resulted in average recoveries of 57.4%, 64.5% and 64.6% in three vegetables for E. coli O157:H7, L. monocytogenes and Salmonella with corresponding detection limits of 10³, 10² and 10³ CFU/g, respectively. Based on these results, it can be concluded that the procedure herein is suitable to recover, detect and quantify enteric viruses and foodborne pathogenic bacteria within 5 h and can be applied for the simultaneous detection of both types of foodborne pathogens in fresh-cut vegetables.

  2. Salicylic acid inhibits enzymatic browning of fresh-cut Chinese chestnut (Castanea mollissima) by competitively inhibiting polyphenol oxidase.

    Science.gov (United States)

    Zhou, Dan; Li, Lin; Wu, Yanwen; Fan, Junfeng; Ouyang, Jie

    2015-03-15

    The inhibitory effect and associated mechanisms of salicylic acid (SA) on the browning of fresh-cut Chinese chestnut were investigated. Shelled and sliced chestnuts were immersed in different concentrations of an SA solution, and the browning of the chestnut surface and interior were inhibited. The activities of polyphenol oxidase (PPO) and peroxidase (POD) extracted from chestnuts were measured in the presence and absence of SA. SA at concentrations higher than 0.3g/L delayed chestnut browning by significantly inhibiting the PPO activity (P0.05). The binding and inhibition modes of SA with PPO and POD, determined by AUTODOCK 4.2 and Lineweaver-Burk plots, respectively, established SA as a competitive inhibitor of PPO.

  3. Nutrient solution aeration and growing cycles affect quality and yield of fresh-cut baby leaf red lettuce

    Directory of Open Access Journals (Sweden)

    Encarnación Conesa

    2015-12-01

    Full Text Available The objective of this research was to study the effects of nutrient solution aeration [no aeration (NA, low aeration (LA or high aeration (HA] and growing cycle (autumn, winter and summer on the yield, quality, and shelf life of red lettuce as a fresh-cut product grown in a floating system. The specific leaf area, yield and root diameter were affected by the growing cycle. The percentage of dry matter and the nitrate content were affected by growing cycle and aeration, total phenolics and mesophilic microorganism by aeration and storage time, hue angle and chromacity by growing cycle and storage time, and antioxidant capacity, vitamin C, lightness and psychrophilic microorganisms were affected by all three factors. NA conditions increased the antioxidant capacity in summer and vitamin C content in winter. The lowest mesophilic and psychrophilic count was observed in autumn. The effect of aeration on most of the quality parameters measured was influenced by the growing cycle.

  4. [Effect of blanching and hygroscopic coating on quality of fresh cut carrots (Daucus carota var. chantenay) during storage].

    Science.gov (United States)

    Uquiche Carrasco, Edgar; Cisneros-Zevallos, Luis

    2002-06-01

    The effect of blanching at low temperatures (solution 1% acid citric, 50 degrees C for 30 seconds) and the application of glycerol as humectant (3% p/p, 20 seconds) to preserve the quality of fresh-cut carrots (Daucus carota) were studied as individual or combined treatments. Four treatments were evaluated: a control by dipping samples for 30 seconds in distilled water (T1); blanching (T2); glycerol application (T3); and blanching plus glycerol application (T4). Total carotenoids content, color, soluble solids and weight loss were monitored during storage. Results showed no differences between treatments in carotenoids content (p > 0.10) and soluble solids (p > 0.05). However, differences were observed between treatments in weight loss (p Blanched samples (T2 and T4) showed small changes in orange color intensity compared to treatments T1 and T3 (p < 0.05).

  5. Pre-harvest muskmelon fruit cracking: causes and potential remedies

    Science.gov (United States)

    Fruit cracking is a serious disorder that causes a major loss of marketable yield and revenue in the muskmelon (Cucumis melo L.) fruit industry. The physiological and environmental factors causing cracking are poorly understood. Although generally considered a physiological disorder caused by fluctu...

  6. Gas permeability and thermal behavior of polypropylene films used for packaging minimally processed fresh-cut potatoes: a case study.

    Science.gov (United States)

    Siracusa, Valentina; Blanco, Ignazio; Romani, Santina; Tylewicz, Urszula; Dalla Rosa, Marco

    2012-10-01

    This work reports an experimental study on the permeability and thermal behavior of commercial polypropylene (PP) film used for fresh-cut potatoes packaging. The permeability was tested using oxygen, carbon dioxide, nitrogen, mix of these 3 gases, normally used for modified atmosphere packaging (MAP) and Air, to understand if it would be possible to extend the shelf life of this food product designed for the catering field in respect to the packaging behavior. The temperature influence on permeability data, from 5 to 40 °C, was analyzed, before and after 4, 8, 12, 15, and 20 d of food contact, pointing out the dependence between temperature and gas transmission rate (GTR), solubility (S), diffusion coefficient (D), and time lag (t(L)) parameters. The activation energies (E) of the permeation process were determined with the different gases used in the experiments. The thermal behavior of PP film was studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TG) to well understand its thermal stability. Fourier transformed-infrared with attenuated total reflectance (FT-IR/ATR) spectroscopy was also performed in order to study the influence of the food contact on the chemical characteristics of the polymer film. The results obtained were discussed and compared each other. Studied samples showed, for all investigated gases, an increase of gas permeability and S values at higher temperature. Heat resistance classification among the sample as it is and stored in modified atmospheres was made. Finally all performed experiments have showed good polymer stability for the shelf-life storage potatoes under study. Study of packaging material was performed in a range of temperature, which can simulate the service condition to assess the suitability of a commercial polymer film for modified atmosphere packaging of fresh-cut potatoes minimally processed designed for catering purpose. © 2012 Institute of Food Technologists®

  7. Impacts of sodium chlorite combined with calcium chloride, and calcium ascorbate on microbial population, browning, and quality of fresh-cut rose apple

    Directory of Open Access Journals (Sweden)

    Sunthon Mola

    2016-09-01

    Full Text Available Microbial activity and browning were minimized and fresh-cut rose apple quality was maintained using sodium chlorite (SC combined with calcium chloride (CC and calcium ascorbate (CaAs and by investigating the optimal concentration and dipping time of SC for inhibiting microbial activity and browning. Fresh-cut rose apple samples were dipped in SC solution at 100 mg/L and 200 mg/L for 1 min and 3 min, with filtered water and non-dipped samples as controls. All samples were kept at 4 ± 2 °C for 9 d. The results showed that 200 mg/L SC for 3 min was the best treatment to inhibit microbial growth (total bacteria, yeast and molds, Escherichia coli and coliforms, delay browning and polyphenol oxidase (PPO activity of fresh-cut rose apples, but could not maintain the fresh firmness. A firmness experiment was conducted by dipping fresh-cut rose apples in 200 mg/L SC and in 200 mg/L SC combined with 20 g/L CC and 20 g/L CaAs (SC + CC + CaAs for 3 min before storage at 4 ± 2 °C for 9 d. Samples immersed in filtered water were used as the control. The combined treatment delayed microbial contamination and browning by reducing the PPO activity and the accumulation of phenolic content, and maintained the fresh firmness of fresh-cut rose apples. Thus, the combination treatment of SC + CC + CaAs solution can protect fresh-cut rose apples against microbial contamination and delay browning and maintain firmness.

  8. Effect of high oxygen and high carbon dioxide atmosphere packaging on the microbial spoilage and shelf-life of fresh-cut honeydew melon.

    Science.gov (United States)

    Zhang, Bao-Yu; Samapundo, Simbarashe; Pothakos, Vasileios; Sürengil, Göknur; Devlieghere, Frank

    2013-09-16

    This study evaluated the potential of modified atmospheres (MAs) combining high oxygen (O₂) and high carbon dioxide (CO₂) levels to extend the shelf-life of fresh-cut honeydew melon. Firstly, the effect of MA on the growth and volatile organic metabolite production of Candida sake, Leuconostoc mesenteroides and Leuconostoc gelidum, which had all been previously isolated from spoiled commercial fresh-cut honeydew melon, was evaluated separately on honeydew melon agar at 7 °C. Additionally, the effect of selected MAs on the microbial, physico-chemical and sensory quality of commercial fresh-cut honeydew melon cubes was evaluated at 7 °C. The results showed that MAs with high O₂ and high CO₂ levels greatly retarded the growth, CO₂ and volatile metabolite production (i.e. ethanol, 2-methyl-1-butanol, ethyl acetate, phenylacetic acid, nonanal) of C. sake on honeydew melon agar; especially MAs consisting of 50% O₂+50% CO₂ and 70% O₂+30% CO₂. In contrast, the MAs evaluated only had a minor effect on the growth and volatile metabolite production of L. mesenteroides and L. gelidum. Overall, the effect of MAs on colour, juice leakage, juiciness, and firmness of fresh-cut honeydew melon was small during storage. Sensory preference was generally for fresh-cut honeydew melon cubes packaged in MA of 50% O₂+50% CO₂. These were still acceptable on day five of storage and had appreciably lower populations of yeasts and lactic acid bacteria, lower quantities of volatile organic compounds, but slightly stronger colour oxidation compared to honeydew melon that was packaged in air. Additionally, most of the samples packed in air had blown by day five due to the large quantity of CO₂ production during storage. Therefore, 50% O₂+50% CO₂ is a potential MA solution for extending the shelf-life of fresh-cut honeydew melon.

  9. Total phenolics, carotenoids, ascorbic acid, and antioxidant properties of fresh-cut mango (Mangifera indica L., cv. Tommy Atkin) as affected by infrared heat treatment.

    Science.gov (United States)

    Sogi, D S; Siddiq, M; Roidoung, S; Dolan, K D

    2012-11-01

    Mango (Mangifera indica L.) is a major tropical fruit that has not been exploited for fresh-cut or minimally processed products on a scale similar to apples, pineapples, or melons. The objective of this study was to investigate the effect of infrared (IR) treatment on total phenolics, carotenoids, ascorbic acid, and antioxidant properties of fresh-cut cubes from 'Tommy Atkin' mangoes. Mango cubes were IR treated (5, 10, 15 min) and evaluated at 4-d intervals during 16-d storage at 4 ± 1 °C. Total phenolics, carotenoids, and ascorbic acid content in fresh-cut control mango cubes were 43.33, 1.37, and 15.97 mg/100 g FW, respectively. IR treatments increased total phenolics (59.23 to 71.16 mg/100 g FW) and decreased ascorbic acid (12.14 to 15.38 mg/100 g, FW). Total carotenoids showed a mixed trend (1.13 to 1.66 mg/100 g, FW). The IR treatment showed a significant positive impact on antioxidant properties (μM TE/100 g, FW) of mango cubes, as assayed by ABTS (261.5 compared with 338.0 to 416.4), DPPH (270.5 compared with 289.4 to 360.5), and ORAC (6686 compared with 8450 to 12230). Total phenolics, carotenoids, ascorbic acid, and antioxidant capacity decreased over 16-d storage. However, IR treated samples had consistently higher ABTS, DPPH, and total phenolics during storage. It was demonstrated that IR treatment can be effectively used in improving antioxidant properties of fresh-cut mangoes with minimal effect on the visual appearance. Various methods/treatments are in use for extending the quality of fresh-cut fruits, including mild heat treatment. This study explored the application of infrared (IR) heat for processing fresh-cut mango cubes and evaluated its effect on vitamin C and antioxidant capacity during 16-d storage. This is the first study reporting on the use of IR heat in fresh-cut fruits. IR treatment was shown to be effective in retaining antioxidant properties of fresh-cut mango cubes with minimal effect on the visual appearance. © 2012 Institute

  10. Ozone damage detection in cantaloupe plants

    Science.gov (United States)

    Gausman, H. W.; Escobar, D. E.; Rodriguez, R. R.; Thomas, C. E.; Bowen, R. L.

    1978-01-01

    Ozone causes up to 90 percent of air pollution injury to vegetation in the United States; excess ozone affects plant growth and development and can cause undetected decrease in yields. Laboratory and field reflectance measurements showed that ozone-damaged cantaloupe (Cucumis melo L.) leaves had lower water contents and higher reflectance than did nondamaged leaves. Cantaloupe plants which were lightly, severely, and very severely ozone-damaged were distinguishable from nondamaged plants by reflectance measurements in the 1.35- to 2.5 micron near-infrared water absorption waveband. Ozone-damaged leaf areas were detected photographically 16 h before the damage was visible. Sensors are available for use with aircraft and spacecraft that possibly could be used routinely to detect ozone-damaged crops.

  11. Ozone damage detection in cantaloupe plants

    Energy Technology Data Exchange (ETDEWEB)

    Gausman, H.W.; Escobar, D.E.; Rodriguez, R.R.; Thomas, C.E.; Bowen, R.L.

    1978-04-01

    Ozone causes up to 90 percent of air pollution injury to vegetation in the United States; excess ozone affects plant growth and development and can cause undetected decrease in yields. Laboratory and field reflectance measurements showed that ozone-damaged cantaloupe (Cucumis melo L.) leaves had lower water contents and higher reflectance than did nondamaged leaves. Cantaloupe plants which were lightly, severely, and very severely ozone-damaged were distinguishable from nondamaged plants by reflectance measurements in the 1.35 to 2.5-..mu..m near-infrared water absorption waveband. Ozone-damaged leaf areas were detected photographically 16 h before the damage was visible. Sensors are available for use with aircraft and spacecraft that possibly could be used routinely to detect ozone-damaged crops. 21 references, 3 figures.

  12. Effect of Chlorine Dioxide and Ascorbic Acid on Enzymatic Browning and Shelf Life of Fresh-Cut Red Delicious and Granny Smith Apples

    NARCIS (Netherlands)

    Remorini, Damiano; Landi, Marco; Tardelli, Francesca; Lugani, Arianna; Massai, Rossano; Graziani, Giulia; Fogliano, Vincenzo; Guidi, Lucia

    2015-01-01

    In this work, we tested the hypothesis that ascorbic acid (AA) reduces browning of fresh-cut apples (Red Delicious, RD, and Granny Smith, GS), and we investigated the impact of AA on phenylpropanoid metabolism of RD and GS. Apple slices were dipped in a solution of 100mg/L of chlorine dioxide (Cl

  13. Low intensity monochromatic red, blue or green light increases the carbohydrate levels and substantially extends the shelf life of fresh-cut lettuce

    NARCIS (Netherlands)

    Woltering, E.J.; Seifu, Y.W.

    2015-01-01

    During dark storage of fresh-cut product prepared from butterhead and iceberg lettuce the levels of carbohydrates (glucose, fructose, sucrose, starch) decrease. Carbohydrate levels were low in butterhead lettuce at the start [~20 mg/g dry matter (DW)] and levels decreased by over 50% during storage

  14. Combination of sodium chlorite and calcium propionate reduces enzymatic browning and microbial population of fresh-cut ‘Granny Smith’ apples

    Science.gov (United States)

    Tissue browning and microbial growth are the main concerns associated with fresh-cut apples. In this study, effects of sodium chlorite (SC) and calcium propionate (CP), individually and combined, on quality and microbial population of apple slices were investigated. ‘Granny Smith’ apple slices, dipp...

  15. Combined effects of sodium chlorite dip treatment and chitosan coatings on the quality of fresh-cut d’Anjou pears

    Science.gov (United States)

    This study evaluated the effects of sodium chlorite (SC) alone and its sequential treatment with edible coatings on browning inhibition and quality maintenance of fresh-cut d’Anjou pears. Edible coatings were prepared from chitosan (CH) and its water soluble derivative: carboxymethyl chitosan (CMCH...

  16. Nitric oxide prevents wound-induced browning and delays senescence through inhibition of hydrogen peroxide accumulation in fresh-cut lettuce

    NARCIS (Netherlands)

    Iakimova, E.T.; Woltering, E.J.

    2015-01-01

    As a source of bioactive ingredients, lettuce is a preferable component of a healthy diet. In recent years the production of fresh-cut produce has become a fast growing business. However, the shreds are highly sensitive to wound-induced browning and premature senescence that substantially reduces th

  17. 鲜切果蔬包装的研究现状与进展%Advance in packaging of fresh-cut fruit and vegetables

    Institute of Scientific and Technical Information of China (English)

    孙炳新; 杨金玲; 赵宏侠; 王晶晶; 吕长鑫; 冯叙桥

    2013-01-01

    Packaging plays an important role in maintaining the quality of,and extending the shelf life of fresh-cut fruit and vegetables.Advance in the studies and applications of packaging materials in relation with the packaging of fresh-cut fruit and vegetables in the last few years was reviewed and their development envisioned. Packaging technologies of fresh-cut fruit and vegetables were introduced, including the gas adjustment packaging,coating packing and intelligent packaging, and the advantages and disadvantages and application status were summarized.At last, the fresh - cut fruit and vegetables packaging development trends in the future were discussed.%包装在维持鲜切果蔬品质、延长货架寿命等方面发挥着重要的作用.本文综述了近年来国内外包装材料在鲜切果蔬保鲜方面的研究进展与应用.介绍了鲜切果蔬的包装技术,包括气调包装、涂膜包装和智能包装等,总结了其优缺点及应用现状,并且讨论了鲜切果蔬包装未来的发展趋势.

  18. Organic acids produced by lactic acid bacteria (Leuconostoc sp.) contribute to sensorial quality loss in modified-atmosphere-packed fresh-cut iceberg lettuce

    NARCIS (Netherlands)

    Paillart, M.J.M.; Vossen, van der J.M.B.M.; Lommen, E.; Levin, E.; Otma, E.C.; Snels, J.C.M.A.; Woltering, E.J.

    2016-01-01

    The shelf-life of fresh-cut lettuce packed in a modified atmosphere (MA) is determined by its "overall visual quality" (OVQ), being a measure of its general appearance based on colour and shape criteria. In addition to the OVQ, the development of off-flavour and acid off-smell reduces consumer ac

  19. Photons and electrons: advances in using cold plasma, irradiation, UV and other energy-based treatments for fresh and fresh-cut produce

    Science.gov (United States)

    Conventional antimicrobial treatments for fresh produce rely on chemical compounds and physical contact to inactivate and remove bacterial contamination. Recent research has identified a number of energy-based alternative technologies to improve the safety of fresh and fresh-cut fruits and vegetable...

  20. Effect of Chlorine Dioxide and Ascorbic Acid on Enzymatic Browning and Shelf Life of Fresh-Cut Red Delicious and Granny Smith Apples

    NARCIS (Netherlands)

    Remorini, Damiano; Landi, Marco; Tardelli, Francesca; Lugani, Arianna; Massai, Rossano; Graziani, Giulia; Fogliano, Vincenzo; Guidi, Lucia

    2015-01-01

    In this work, we tested the hypothesis that ascorbic acid (AA) reduces browning of fresh-cut apples (Red Delicious, RD, and Granny Smith, GS), and we investigated the impact of AA on phenylpropanoid metabolism of RD and GS. Apple slices were dipped in a solution of 100mg/L of chlorine dioxide

  1. Efficacy of gaseous chlorine dioxide on inactivation of Escherichia coli O157:H7 on surfaces of artificially inoculated fresh-cut Romaine lettuce leaves

    Science.gov (United States)

    Efficacy of antimicrobial agents in inactivating pathogenic microorganisms on fresh and fresh-cut produce surfaces in limited by the accessibility of such agents to the produce surfaces where the microorganisms are residing. Other factors contribute to this problem include biofilm formation by the m...

  2. Genome sequences of Ralstonia insidiosa type strain ATCC 49129 and strain FC1138, a strong biofilm producer isolated from a fresh-cut produce-processing plant

    Science.gov (United States)

    Ralstonia insidiosa FC1138 is a strong biofilm producer, isolated from a local fresh-cut produce processing plant. Here, we present the complete genome sequence of Ralstonia insidiosa FC1138 which includes two circular chromosomes and a plasmid. To our knowledge, this is the first reported complete ...

  3. Gram-negative bacterial isolates from fresh-cut processing plants enhance the presence of Escherichia Coli O157:H7 in dual-species biofilms

    Science.gov (United States)

    Biofilms formed by resident microflora may provide a microenvironment for foodborne bacterial pathogens to survive and cause cross-contamination in fresh-cut processing and handling facilities. The objective of this study is to determine the impact of individual bacteria strains isolated from two l...

  4. Effects of pulsed light treatments and pectin edible coatings on the quality of fresh-cut apples: a hurdle technology approach.

    Science.gov (United States)

    Moreira, María R; Álvarez, María V; Martín-Belloso, Olga; Soliva-Fortuny, Robert

    2017-01-01

    Pulsed light (PL) treatments stand as an alternative for the shelf-life extension of fresh-cut products. The antimicrobial effects of PL are well known; however, its influence on quality attributes needs to be assessed. This study was aimed at evaluating the application of PL treatments in combination with pectin-based edible coatings enriched with dietary fiber for the preservation of fresh-cut apples. Dipping of fresh-cut apples in ascorbic acid/calcium chloride solution prior to pectin coating and PL treatments was effective to minimize browning and softening of apple surfaces. Incorporation of fiber in the pectin coating did not cause any change in microbial loads and sensory acceptability of apple cubes. Pectin-coated PL-treated apple pieces exhibited significantly higher antioxidant activity values than fresh and PL control samples. At the end of storage, the combination of both treatments resulted in an almost 2 log CFU g(-1) reduction of microbial counts. Sensory attribute scores did not fall below the rejection limit throughout 14 days, although the presence of off-odors limited the acceptability of the pectin-coated samples. The results demonstrate that PL treatments applied to pectin-coated fresh-cut apples may be used to maintain quality attributes, thus conferring prebiotic potential and extending the shelf-life of the product. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  5. Shelf-life prediction models for ready-to-eat fresh cut salads: Testing in real cold chain.

    Science.gov (United States)

    Tsironi, Theofania; Dermesonlouoglou, Efimia; Giannoglou, Marianna; Gogou, Eleni; Katsaros, George; Taoukis, Petros

    2017-01-02

    The aim of the study was to develop and test the applicability of predictive models for shelf-life estimation of ready-to-eat (RTE) fresh cut salads in realistic distribution temperature conditions in the food supply chain. A systematic kinetic study of quality loss of RTE mixed salad (lollo rosso lettuce-40%, lollo verde lettuce-45%, rocket-15%) packed under modified atmospheres (3% O2, 10% CO2, 87% N2) was conducted. Microbial population (total viable count, Pseudomonas spp., lactic acid bacteria), vitamin C, colour and texture were the measured quality parameters. Kinetic models for these indices were developed to determine the quality loss and calculate product remaining shelf-life (SLR). Storage experiments were conducted at isothermal (2.5-15°C) and non-isothermal temperature conditions (Teff=7.8°C defined as the constant temperature that results in the same quality value as the variable temperature distribution) for validation purposes. Pseudomonas dominated spoilage, followed by browning and chemical changes. The end of shelf-life correlated with a Pseudomonas spp. level of 8 log(cfu/g), and 20% loss of the initial vitamin C content. The effect of temperature on these quality parameters was expressed by the Arrhenius equation; activation energy (Ea) value was 69.1 and 122.6kJ/mol for Pseudomonas spp. growth and vitamin C loss rates, respectively. Shelf-life prediction models were also validated in real cold chain conditions (including the stages of transport to and storage at retail distribution center, transport to and display at 7 retail stores, transport to and storage in domestic refrigerators). The quality level and SLR estimated after 2-3days of domestic storage (time of consumption) ranged between 1 and 8days at 4°C and was predicted within satisfactory statistical error by the kinetic models. Teff in the cold chain ranged between 3.7 and 8.3°C. Using the validated models, SLR of RTE fresh cut salad can be estimated at any point of the cold chain

  6. Processamento mínimo de tangerinas sob duas temperaturas Fresh-cut tangerine stored under two temperatures

    Directory of Open Access Journals (Sweden)

    Clarissa Damiani

    2008-02-01

    Full Text Available Conduziu-se este trabalho para avaliar o efeito de duas temperaturas na qualidade de Tangerina 'Poncã', minimamente processada, durante 12 dias. O processamento mínimo consistiu de lavagem, sanificação, retirada das cascas das frutas e embalagem. Os frutos foram refrigerados a 0ºC e 10ºC. Foram avaliados, a cada três dias, as seguintes variáveis: concentração de O2 e CO2, perda de massa, valor L*, a* e b*, pH, acidez titulável, sólidos solúveis, rendimento do suco, vitamina C e beta-caroteno. Concluiu-se que, as temperaturas de 0ºC e 10ºC, não tiveram influência distinta sobre a cor, teores de vitamina C e beta-caroteno e sólidos solúveis, contudo influenciaram o rendimento do suco, que foi melhor nas frutas armazenadas a 10ºC. A interação temperatura e tempo afetaram a perda de massa e o pH, observando-se que, quanto maior a temperatura e o tempo de armazenamento, maiores são as perdas sofridas pelos frutos minimamente processados.The objective of this work was to evaluate the effect of two temperatures on the quality of fresh-cut Tangerine 'Poncã' during 12 days. The minimal processing consisted of washing, sanitization, the peelling of the fruit and packing. The fruit were cooled at 0ºC and 10ºC. The following variable were evaluated every 3 days: concentration of O2 and CO2, mass loss, L *, a* and b * values, pH, titratable acidity, soluble solids, juiciness, vitamin C and beta-carotene. It was concluded that of temperature at 0ºC and 10ºC did not have different influence on color, vitamin C, beta-carotene and soluble solids, however held the juiciness what was the best in the fruit stored 10ºC. The interaction temperature and time affected the mass loss and pH, observing that the bigger temperature and the time of storage, the bigger are the losses suffered for the fresh-cut fruits.

  7. Erwinia tracheiphila colonization of cantaloupe fruits through flower inoculation

    Science.gov (United States)

    Cantaloupe (Cucumis melo var. cantalupensis) is a nutritious fresh fruit. Bacterial wilt, caused by Erwinia tracheiphila, is the most devastating cantaloupe disease globally. The pathogen is transmitted in nature by xylem-feeding spotted and striped cucumber beetles; other modes of infection have ...

  8. Effect of postharvest ultraviolet-C treatment on the proteome changes in fresh cut mango (Mangifera indica L. cv. Chokanan).

    Science.gov (United States)

    George, Dominic Soloman; Razali, Zuliana; Santhirasegaram, Vicknesha; Somasundram, Chandran

    2016-06-01

    Postharvest treatments of fruits using techniques such as ultraviolet-C have been linked with maintenance of the fruit quality as well as shelf-life extension. However, the effects of this treatment on the quality of fruits on a proteomic level remain unclear. This study was conducted in order to understand the response of mango fruit to postharvest UV-C irradiation. Approximately 380 reproducible spots were detected following two-dimensional gel electrophoresis. Through gel analysis, 24 spots were observed to be differentially expressed in UV-C treated fruits and 20 were successfully identified via LCMS/MS. Postharvest UV-C treatment resulted in degradative effects on these identified proteins of which 40% were related to stress response, 45% to energy and metabolism and 15% to ripening and senescence. In addition, quality and shelf-life analysis of control and irradiated mangoes was evaluated. UV-C was found to be successful in retention of quality and extension of shelf-life up to 15 days. Furthermore, UV-C was also successful in increasing antioxidants (total flavonoid, reducing power and ABTS scavenging activity) in mangoes. This study provides an overview of the effects of UV-C treatment on the quality of mango on a proteomic level as well as the potential of this treatment in shelf-life extension of fresh-cut fruits. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  9. Short UV-C Treatment Prevents Browning and Extends the Shelf-Life of Fresh-Cut Carambola

    Directory of Open Access Journals (Sweden)

    Carlota Moreno

    2017-01-01

    Full Text Available In this work, we selected a short UV-C treatment for fresh-cut carambola and assessed its efficacy in supplementing the benefits of low temperature storage. UV-C treated (6.0, 10.0, and 12.5 kJ m−2 carambola slices showed reduced deterioration compared to control fruit. Treatment with a dose of 12.5 kJ m−2 UV-C was more effective in maintaining quality and was selected for subsequent experiments evaluating the combination of UV-C and refrigeration on fruit storability and physical, chemical, and microbiological properties. Short UV-C exposure reduced weight loss and electrolyte leakage. UV-C treated carambola slices presented higher phenolic antioxidants than control after 21 d at 4°C and showed no alterations in soluble solids or titratable acidity. UV-C exposure also reduced the counts of molds, yeast, and aerobic mesophilic bacteria. UV-C treated fruit showed a fresh-like appearance even after 21 d as opposed to control carambola which presented spoilage and extensive browning symptoms. The reduction of fruit browning in UV-C treated fruit was not due to reduction in phenylalanine-ammonia lyase (PAL and/or peroxidase (POD, but rather through polyphenol oxidase (PPO inhibition and improved maintenance of tissue integrity.

  10. Quality changes of fresh-cut pomegranate arils during shelf life as affected by deficit irrigation and postharvest vapour treatments.

    Science.gov (United States)

    Peña-Estévez, María E; Gómez, Perla A; Artés, Francisco; Aguayo, Encarna; Martínez-Hernández, Ginés Benito; Otón, Mariano; Galindo, Alejandro; Artés-Hernández, Francisco

    2015-08-30

    The effect of two sustained deficit irrigation (SDI) strategies, compared to a control, on postharvest physicochemical, microbial, sensory quality attributes and anthocyanin content of fresh-cut pomegranates arils throughout 18 days at 5 °C was studied. Furthermore, the effect of vapour treatments (4, 7 and 10 s) compared to a conventional sanitizing treatment with NaClO on such quality parameters in combination with the preharvest treatments was also studied. According to sensory analyses, the shelf life of arils from control and SDI-irrigated fruit was established in 14 and 18 days at 5 °C, respectively, showing 4 and 7 s vapour treatment time the best sensory quality. No significant change was observed in physicochemical quality attributes, across all treatments during storage, while low microbial loads were registered (<3 log CFU g(-1)) after shelf life. Postharvest treatments that had least effect on anthocyanin content on processing day were 7 and 10 s. Vapour treatments of 7-10 s applied to pomegranate arils led to an extended shelf life up to 18 days at 5 °C with better results in SDI-irrigated samples with a water saving of 6-11%. © 2014 Society of Chemical Industry.

  11. Improved quality of a vitamin B12-fortified 'ready to blend' fresh-cut mix salad with chitosan.

    Science.gov (United States)

    Artés-Hernández, Francisco; Formica-Oliveira, Anna Carolina; Artés, Francisco; Martínez-Hernández, Ginés Benito

    2017-01-01

    A vitamin B12-fortified (0.25 mg L(-1)) chitosan (10 g L(-1)) coating was applied to a ready-to-blend fresh-cut salad including melon, pineapple and carrot, which was stored at 5 ℃ up to nine days. Uncoated samples were used as control while the vitamin B12 effect was compared to non-fortified chitosan-coated samples. Beverages were prepared on blending days 0, 4, 7 and 9 with subsequent storage at 5 ℃ for 0, 24 and 48 h. Physicochemical quality of fresh blended beverages was well preserved throughout storage. The chitosan coating highly reduced epiphytic microflora growth and polyphenoloxidase/peroxidase activities. No relevant variations of total phenolic contents were observed between different fresh blended beverages. However, its total antioxidant capacity reported after blending was lower as storage time of ready-to-blend samples increased. Fortified samples showed a vitamin B12 content of 8.6 µg kg(-1) on processing day, ensuring 200 mL of such beverage the recommended daily intake of this vitamin. In conclusion, a ready-to-blend fruit/vegetable mix, fortified with vitamin B12, was developed with a shelf life of nine days at 5 ℃ showing the prepared beverages good quality during subsequent storage for 48 h at 5 ℃.

  12. Preliminary Investigations of the Anti-asthmatic Properties of the Aqueous Extract of Justicia pectoralis (Fresh Cut).

    Science.gov (United States)

    Cameron, C; Jacob, A S; Thomas, E A; Levy, A S

    2015-09-01

    Justicia pectoralis (fresh cut plant), family Acantheceae, is a herb that is native to central America and the Caribbean. A crude extract prepared from the leaves of Justicia pectoralis is commonly used in Jamaican ethnotraditional medicine to reduce difficulty in breathing and suppress wheezing in asthmatic individuals. To investigate the anti-inflammatory and antihistamine activity of an aqueous extract of Justicia pectoralis. In in vivo experiments, guinea pigs were sensitized by the method of Weinrich and Undem (1987). The effect of water on the wheals was assessed in the control group, n = 4. The effect of 3.3 mg of the crude extract was noted in histamine-induced wheals over a period of three hours. The extract was injected via intraperitoneal injections. In in vitro experiments, 3.3 mg of crude sample was tested for its effectiveness against histamine-induced tracheal contraction caused by cumulative dosing of histamine. The crude extract was efficacious in reducing the formation of histamine-induced wheals (p Justicia pectoralis reduced the formation of histamine-induced wheals in sensitized guinea pigs (p < 0.05) and also reduced histamine-induced tracheal smooth muscle contractions (p < 0.05). It blocked the effect of contraction produced by histamine in the airways; this property supports folklore claims for its use as an antihistamine.

  13. Muskmelon seed priming in relation to seed vigor

    Directory of Open Access Journals (Sweden)

    Nascimento Warley Marcos

    2004-01-01

    Full Text Available A number of important factors may affect seed priming response, including seed quality. Effects of seed vigor on seed priming response were investigated using seed lots of two muskmelon (Cucumis melo L. cultivars. Seeds of muskmelon, cvs. Mission and Top Net SR were artificially aged at 43°C for 0, 20 and 40 hours. Seeds were primed for six days in darkness at 25°C in KNO3 (0.35 mol L-1 aerated solution. Aged seeds germinated poorly at 17°C. Priming increased germination rate at 17 and 25°C and germination percentage at 17°C. An interaction effect on germination performance between vigor and priming was observed, especially at low temperature. Priming increased germination performance in seeds of low vigor, and the response was cultivar dependent.

  14. Effect of a bacteriophage cocktail in combination with modified atmosphere packaging in controlling Listeria monocytogenes on fresh-cut spinach

    Directory of Open Access Journals (Sweden)

    Boyacioglu O.

    2016-06-01

    Full Text Available A Listeria monocytogenes-specific bacteriophage cocktail was evaluated for its activity against a nalidixic acid-resistant L. monocytogenes (Lm-NalR isolate on fresh-cut spinach stored under modified atmosphere packaging at various temperatures. Pieces (~2 × 2 cm2 of fresh spinach inoculated with 4.5 log CFU/cm2 Lm-NalR were sprayed with the phage cocktail (6.5 log plaque-forming units [PFU]/cm2 or a control. The samples were stored at 4°C or 10°C for up to 14 d in sealed packages filled with either atmospheric air (AA or modified atmosphere (MA. At 4°C under AA, the phages significantly (P ≤ 0.05 lowered the Lm-NalR populations on spinach, compared to control-treated inoculated samples, by 1.12 and 1.51 log CFU/cm2 after 1 and 14 d, respectively. At 4°C under MA, Lm-NalR was significantly reduced by 1.95 log CFU/cm2 compared to control leaves after both 1 and 14 d. At 10°C under AA, the phages significantly reduced Lm-NalR by 1.50 and 2.51 log CFU/cm2 after 1 and 14 d compared to the control. Again at 10°C under MA, the phages significantly reduced Lm-NalR by 1.71 and 3.24 log CFU/cm2 compared to control after 1 and 14 d, respectively. The results support the potential of lytic bacteriophages in effectively reducing populations of L. monocytogenes on freshcut leafy produce, under both AA and MA conditions.

  15. Relative effectiveness of the Bacteriological Analytical Manual method for the recovery of Salmonella from whole cantaloupes and cantaloupe rinses with selected preenrichment media and rapid methods.

    Science.gov (United States)

    Hammack, Thomas S; Valentin-Bon, Iris E; Jacobson, Andrew P; Andrews, Wallace H

    2004-05-01

    Soak and rinse methods were compared for the recovery of Salmonella from whole cantaloupes. Cantaloupes were surface inoculated with Salmonella cell suspensions and stored for 4 days at 2 to 6 degrees C. Cantaloupes were placed in sterile plastic bags with a nonselective preenrichment broth at a 1:1.5 cantaloupe weight-to-broth volume ratio. The cantaloupe broths were shaken for 5 min at 100 rpm after which 25-ml aliquots (rinse) were removed from the bags. The 25-ml rinses were preenriched in 225-ml portions of the same uninoculated broth type at 35 degrees C for 24 h (rinse method). The remaining cantaloupe broths were incubated at 35 degrees C for 24 h (soak method). The preenrichment broths used were buffered peptone water (BPW), modified BPW, lactose (LAC) broth, and Universal Preenrichment (UP) broth. The Bacteriological Analytical Manual Salmonella culture method was compared with the following rapid methods: the TECRA Unique Salmonella method, the VIDAS ICS/SLM method, and the VIDAS SLM method. The soak method detected significantly more Salmonella-positive cantaloupes (P < 0.05) than did the rinse method: 367 Salmonella-positive cantaloupes of 540 test cantaloupes by the soak method and 24 Salmonella-positive cantaloupes of 540 test cantaloupes by the rinse method. Overall, BPW, LAC, and UP broths were equivalent for the recovery of Salmonella from cantaloupes. Both the VIDAS ICS/SLM and TECRA Unique Salmonella methods detected significantly fewer Salmonella-positive cantaloupes than did the culture method: the VIDAS ICS/SLM method detected 23 of 50 Salmonella-positive cantaloupes (60 tested) and the TECRA Unique Salmonella method detected 16 of 29 Salmonella-positive cantaloupes (60 tested). The VIDAS SLM and culture methods were equivalent: both methods detected 37 of 37 Salmonella-positive cantaloupes (60 tested).

  16. Effects of different storage temperature on fresh-cut lettuce during storage period%贮藏温度对鲜切莴笋品质的影响

    Institute of Scientific and Technical Information of China (English)

    杨霞; 舒晓斌; 吴广辉; 毕韬韬; 高愿军

    2011-01-01

    以莴笋为原料,研究贮藏温度(2,8,25℃)对鲜切莴笋贮藏期间失重率、呼吸强度、PPO活性、ΔE值、Vc含量、菌落总数和感官指标等理化指标的影响.结果表明,鲜切莴笋在2℃和8℃的低温下贮藏能有效降低失重率,抑制呼吸作用和Vc损失,降低PPO活性,减轻酶促褐变,控制微生物的生长和繁殖,贮藏12d后仍具有良好的感官指标,其中2℃下贮藏保鲜效果最好.%Fresh cut lettuces were used to study the effects of three different storage temperature (2,8 and 25 ℃) on physiology indexes such as weight lose? Respiration intensity* FPO activity, △E value, content of Vc, the total of bacteria and sensory indexes of fresh cut lettuce during storage period. The results showed that: it could inhibit the weight lose, respiration intensity, PPO activity, enzymatic browning, oxidization of Vc, growth and reproduction of microbial, when the fresh-cut lettuces were stored under a lower temperature (2 and 8℃). And they still had good sensory indexes after storing for 12 day. It had the best effect of fresh keeping, when the fresh-cut lettuces were stored under 2 ℃

  17. Effects of rind removal on physicochemical quality characteristics of fresh-cut watermelon [Citrus lanatus (Thunb) Matsum & Nakai] during cold storage

    NARCIS (Netherlands)

    Petrou, P.; Soteriou, G.; Schouten, R.E.; Kyriacou, C.

    2013-01-01

    The impact of removing the rind from fresh-cut watermelon slices was assessed on the quality of the product during storage at 4 °C for 9 days. Flesh lycopene declined from 55.4 to 47.9 mg kg-1 f.w. and colour lightness (L*) increased from 43.2 to 45.8 after 2 days of storage. Initial heart and place

  18. Heat shock and UV-C abiotic stress treatments as alternative tools to promote fresh-cut carrot quality and shelf-life

    OpenAIRE

    Alegria, Carla Sofia Marques

    2015-01-01

    Doutoramento em Engenharia Alimentar - Instituto Superior de Agronomia Abiotic stress treatments, heat shock (HS_100 ºC/45 s) and UV-C (0.1-5 kJ.m-2), and two passive modified atmosphere packaging conditions were evaluated under the hurdle concept as alternative approaches to the standard processing of fresh-cut carrot (FCC). The significant phenolic accumulation, via phenylalanine-ammonia lyase activation, showed to be independent on key factors contributing to raw material bioactivity, c...

  19. Effectiveness of hydrothermal-calcium chloride treatment and chitosan on quality retention and microbial growth during storage of fresh-cut papaya.

    Science.gov (United States)

    Ayón-Reyna, Lidia E; Tamayo-Limón, Ransés; Cárdenas-Torres, Feliznando; López-López, Martha E; López-Angulo, Gabriela; López-Moreno, Héctor S; López-Cervántes, Jaime; López-Valenzuela, José A; Vega-García, Misael O

    2015-03-01

    Rapid degradation of fresh-cut papaya limits its marketability. Hydrothermal treatments in combination with a calcium dip, applied to whole fruit before slicing, and also the application of chitosan as a coating film, have been found to have very good results in maintaining the quality of fresh-cut fruits. Based on these considerations, the aim of this study was to evaluate the effect of hydrothermal treatment (HT; 49 °C, 25 min) containing calcium chloride (Ca; 1%, w/v) followed by dipping in chitosan (Chit; 1%, w/v, 3 min) on the physical, chemical, and microbial qualities of papaya slices stored at 5 °C for 10 d. Pulp color, firmness, ascorbic acid, total phenolics, β-carotene, and lycopene were evaluated every 2 d while the microbial quality (mesophilics, psychrophilics, molds, and yeasts) was evaluated every 5 d. Fruit treated with HT-Ca and HT-Ca + Chit showed better color and firmness retention than Control and Chit. Papaya slices treated with HT-Ca + Chit had higher nutritional content and lower microbial growth at the end of storage. The application of the HT-Ca + Chit could be used to reduce deterioration processes, maintaining physical, chemical, and microbial qualities and increasing the shelf life of fresh-cut papaya stored at 5 °C.

  20. Detection of postharvest changes of ascorbic acid in fresh-cut melon, kiwi, and pineapple, by using a low cost telemetric system.

    Science.gov (United States)

    Barberis, Antonio; Fadda, Angela; Schirra, Mario; Bazzu, Gianfranco; Serra, Pier Andrea

    2012-12-01

    The present paper deals with a novel telemetric device combined with a carbon amperometric sensor system to determine postharvest changes of ascorbic acid (AA) in fresh-cut fruits, without displacing products out of the storage rooms. The investigation was performed on kiwi, pineapple and melon, subjected to minimal processing, packaging, cold storage, and simulated shelf life. Results demonstrated that AA content of fresh-cut fruits of all species declines differently during storage. Cold storage notably reduced the degradation rate of AA in comparison with samples stored at 20°C. The cold-chain interruption resulted in a sharp AA content reduction when the optimal storage condition was not rapidly replaced. Unpredicted results showed a high activity of oxidative enzymes, which prevented AA detection in melon samples. Our sensor system allowed us to demonstrate that both ascorbate peroxidase and ascorbate oxidase affected the oxidative stability and the nutritional quality of fresh cut melon fruits. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Effect of short-term air storage after removal from controlled-atmosphere storage on apple and fresh-cut apple quality.

    Science.gov (United States)

    Toivonen, Peter M A; Wiersma, Paul A; Hampson, Cheryl; Lannard, Brenda

    2010-03-15

    One of the realities of apple distribution for long-term stored fruit is that a controlled-atmosphere (CA) storage room will be unsealed and fruit held in air storage and marketed over several weeks. This work was conducted to determine the effect of post-CA air storage of whole fruit on potential shelf life for fresh-cut apple slices. Fresh-cut slices of 'Spartan' and 'Delicious' apples held in post-CA air storage for 2 or 4 weeks showed the least changes in cut surface color as compared with those made from apples immediately on removal from CA. Shelf life was most improved by post-CA air storage in the 'Spartan' apples, which were more advanced in maturity as compared with the 'Delicious' apples. Internal ethylene concentration, firmness, and respiration changed significantly with post-CA air storage, suggesting a relationship between physiological status of the whole fruit and shelf life of slices made from that fruit. The results support the hypothesis that apples had suppressed physiological activity in CA storage and are susceptible to accelerated deterioration upon cutting. Holding fruit for 2 weeks in air storage allowed recovery of physiological activity, which resulted in greater resistance to deterioration in response to fresh-cut processing.

  2. Effect of Gelatin-Based Edible Coatings Incorporated with Aloe vera and Black and Green Tea Extracts on the Shelf Life of Fresh-Cut Oranges

    Directory of Open Access Journals (Sweden)

    Mohsen Radi

    2017-01-01

    Full Text Available The aim of this study was to evaluate the effect of gelatin coating incorporated with Aloe vera gel (50,100% and green and black tea extracts (5,10% on physicochemical, microbial, and sensorial properties of fresh-cut oranges at 4°C for 17 days. Significant differences in terms of quality parameters were observed between the control and coated fresh-cut oranges. The highest variation of quality parameters was observed in control, while the least variations were observed in coated slices with 100% Aloe vera and 10% green tea extract. The weight loss was increased with time, but the coating treatment especially with 100% Aloe vera had significant effect on the prevention of weight loss. Also, Aloe vera coated samples obtained the highest score in sensory evaluation. Coating with gelatin incorporated with Aloe vera and green tea extracts successfully retarded the microbial growth and therefore extended the shelf life of fresh-cut oranges during cold storage.

  3. Etiology, development and reaction of muskmelon to vine decline under arid conditions of Oman

    Directory of Open Access Journals (Sweden)

    Qais Saif Al-MAWAALI

    2014-01-01

    Full Text Available Muskmelon vine decline is considered the most important factor limiting muskmelon production in Oman. This study was conducted to characterize incidence, development, causal agents and response of muskmelon cultivars to this disease. A survey showed that incidence of the disease ranged from 0 to 15% (mean 5% in spring 2011, 1 to 80% (mean 18% in autumn 2011 and 0 to15% (mean 10% in spring 2012. Isolations from 168 affected plants yielded Pythium aphanidermatum (56% of diseased plants sampled, Fusarium spp. (46%, Monosporascus cannonballus (27%, Rhizoctonia solani (22% and Macrophomina phaseolina (1%. In pathogenicity tests, R. solani, M. cannonballus and P. aphanidermatum were found to be pathogenic to muskmelon. In another experiment over three seasons, M. cannonballus, P. aphanidermatum and R. solani were consistently isolated from muskmelon plants on a weekly basis from 14 days after sowing until the end of the season. However, symptom development only began with the onset of fruiting, which suggests that fruiting stress may be a factor in vine decline disease development. Field assessment of 11 muskmelon cultivars showed that ‘Shahd F1’ was one of the cultivars least susceptible to vine decline and was relatively high yielding. This is the first record of M. cannonballus as a causal agent of muskmelon vine decline in Oman.

  4. Effect of cassava starch coating on quality and shelf life of fresh-cut pineapple (Ananas comosus L. Merril cv "Pérola").

    Science.gov (United States)

    Bierhals, Vânia S; Chiumarelli, Marcela; Hubinger, Miriam D

    2011-01-01

    This research studied the influence of treatment with ascorbic acid, citric acid, and calcium lactate dipping and cassava starch edible coatings on quality parameters and shelf life of fresh-cut pineapple in slices during 12 d at 5 °C. After previous tests, the treatments selected for this study were samples dipped into antibrowning solution with 0.5% of ascorbic acid and 1% of citric acid, with and without 2% of calcium lactate and coated with 2% of cassava starch suspensions. Changes in weight loss, juice leakage, mechanical properties (stress at failure), color parameters (L* and H*), ascorbic acid content, sensory acceptance, and microbial growth of fruits were evaluated. Samples only treated with antibrowning agents were used as control. Edible coatings with and without calcium lactate were efficient in reducing weight loss, juice leakage, and maintaining firmness during storage. However, these samples showed more browning and the ascorbic acid content was reduced. All treatments presented good sensory acceptance (scores above 6). The determining factor of shelf life of pineapple slices was the microbial spoilage. A shelf life of 8 d was obtained for pineapple slices only treated with antibrowning agents. On the other hand, coated samples showed a reduced shelf life of 7 d and higher yeast and mold growth. Thus, although cassava starch coatings were efficient in reducing respiration rate, weight loss, and juice leakage and maintained mechanical properties, these treatments were not able to increase the shelf life of minimally processed pineapple. Practical Application: Pineapple fruit is highly appreciated for its aroma, flavor, and juiciness, but its immediate consumption is difficult. Therefore, pineapple is a potential fruit for minimal processing. However, shelf life of fresh-cut pineapple is very limited by changes in color, texture, appearance, off-flavors, and microbial growth. The use of edible coatings as gas and water vapor barrier and antibrowning

  5. Combination of sodium chlorite and calcium propionate reduces enzymatic browning and microbial population of fresh-cut "Granny Smith" apples.

    Science.gov (United States)

    Guan, Wenqiang; Fan, Xuetong

    2010-03-01

    Tissue browning and microbial growth are the main concerns associated with fresh-cut apples. In this study, effects of sodium chlorite (SC) and calcium propionate (CP), individually and combined, on quality and microbial population of apple slices were investigated. "Granny Smith" apple slices, dipped for 5 min in CP solutions at 0%, 0.5%, 1%, and 2% (w/v) either alone or in combination with 0.05% (w/v) SC, were stored at 3 and 10 degrees C for up to 14 d. Color, firmness, and microflora population were measured at 1, 7, and 14 d of storage. Results showed that CP alone had no significant effect on the browning of cut apples. Even though SC significantly inhibited tissue browning initially, the apple slices turned brown during storage at 10 degrees C. The combination of CP and SC was able to inhibit apple browning during storage. Samples treated with the combination of SC with CP did not show any detectable yeast and mold growth during the entire storage period at 3 degrees C. At 10 degrees C, yeast and mold count increased on apple slices during storage while CP reduced the increase. However, high concentrations of CP reduced the efficacy of SC in inactivating E. coli inoculated on apples. Overall, our results suggested that combination of SC with 0.5% and 1% CP could be used to inhibit tissue browning and maintain firmness while reducing microbial population. Practical Application: Apple slices, which contain antioxidants and other nutrient components, have emerged as popular snacks in food service establishments, school lunch programs, and for family consumption. However, the further growth of the industry is limited by product quality deterioration caused by tissue browning, short shelf-life due to microbial growth, and possible contamination with human pathogens during processing. Therefore, this study was conducted to develop treatments to reduce microbial population and tissue browning of "Granny Smith" apple slices. Results showed that an antimicrobial

  6. Salmonella contamination during production of cantaloupe: a binational study.

    Science.gov (United States)

    Castillo, A; Mercado, I; Lucia, L M; Martínez-Ruiz, Y; Ponce de León, J; Murano, E A; Acuff, G R

    2004-04-01

    Six cantaloupe farms and packing plants in South Texas (950 cantaloupe, 140 water, and 45 environmental samples), including the Rio Grande Valley area, and three farms in Colima State, Mexico (300 cantaloupe, 45 water, and 15 environmental samples), were sampled to evaluate cantaloupe contamination with Salmonella and Escherichia coli during production and processing. Samples collected from external surfaces of cantaloupes, water, and the environments of packing sheds on cantaloupe farms were examined for the presence of Salmonella and E. coli. Of a total of 1,735 samples collected, 31 (1.8%) tested positive for Salmonella. Fifteen Salmonella serotypes were isolated from samples collected in Texas, and nine from samples collected in Colima. Two serotypes (Poona and Oranienburg) that have been associated with three large Salmonella outbreaks in the United States and Canada linked to the consumption of contaminated cantaloupe were found in water samples collected at four farms (three from the United States). Susceptibility of Salmonella isolates to 10 antimicrobials was evaluated by disk diffusion. Eighty-eight percent of the isolates from the United States and Mexico were pansusceptible to the antimicrobials tested; eight isolates from the United States demonstrated an intermediate susceptibility to streptomycin and only two isolates were resistant to the same antimicrobial. From Mexico, four isolates showed an intermediate susceptibility to streptomycin and one isolate was resistant to nalidixic acid and streptomycin. Repetitive sequence-based PCR analysis of Salmonella isolates helped to trace potential sources of Salmonella contamination in source water and in subsequent water samples obtained after the filtration systems of U.S. and Mexican cantaloupe farms. No differences could be seen between the levels of Salmonella contamination in melons from both countries.

  7. Fresh cut cassava subjected to gamma radiationMandioca minimamente processada submetida a radiação gama

    Directory of Open Access Journals (Sweden)

    Mariana Gonçalves Lozano

    2012-04-01

    Full Text Available Fresh cut cassava is an alternative to prolong roots commercialization period, adding value to the raw material and assisting the consumer’s needs that seeks for products of easy preparation. The aim of this work was to evaluate the quality of fresh cut cassava subjected to gamma radiation. For processing cassava roots (IAC – 567-70 were used, after preparation were packed in expanded polystyrene (EPS trays, covered by low density polyethylene (LDPE plastic film, being subjected to gamma radiation in the doses 0 (control, 0.5; 1.0; 1.5; 2.0 KGy. Another treatment was also carried out in which roots were vacuum packed in nylon + polyethylene. Packed roots of all treatments were stored under refrigeration (5 ± 1 ºC and evaluations were made after 0, 3, 6, 9 and 12 days. Evaluated analyses were: titrable acidity, pH, firmness, coloration, polyphenoloxidase activity, cooking time and roots hydration percentage. Evaluations just proceeded until the nine storage day, because after this period the roots already presented visually detectable physiologic and microbiological alterations. For titrable acidity, the vacuum packed roots had the lowest values, followed by the control packed in trays. For the other treatments, values of acidity increased and influenced the pH values. For the other appraised parameters there was no significant difference among treatments, but alterations were observed with the storage. The firmness decreased with the storage. Brightness values and yellow color component decreased with the storage and the b * (green color values increased. Polyphenoloxidase activity was maximum in the day of elaboration of the product and it decreased with the storage. Cooking time and roots hydration percentage decreased with the roots storage.A mandioca minimamente processada é uma alternativa para prolongar o período de comercialização das raízes, agregando de valor a matéria prima e atendendo as necessidades do consumidor que

  8. Internalization of Listeria monocytogenes in cantaloupes during dump tank washing and hydrocooling

    Science.gov (United States)

    Recent listeriosis outbreaks and recalls associated with cantaloupes urge for studies to understand the mechanisms of cantaloupe contamination by Listeria monocytogenes. Postharvest practices such as washing and hydrocooling were suggested to facilitate the contamination of fresh fruits by human pat...

  9. Research advances in biological preservatives of fresh-cut fruits and vegetables%鲜切果蔬中生物保鲜剂的研究进展

    Institute of Scientific and Technical Information of China (English)

    董妍; 胡文忠; 姜爱丽

    2015-01-01

    随着人们对食品质量与安全的要求日益提高,鲜切果蔬保鲜技术迅速发展,生物保鲜剂因具有安全、高效等特点成为鲜切果蔬保鲜的研究热点。鲜切果蔬经分级、清洗、修整、去皮、切分、保鲜、包装等过程处理后,机械损伤、生理代谢、病原微生物污染等问题会引起鲜切果蔬腐烂、品质下降,给鲜活农产品的经济贸易带来了巨大损失,并对人类生命安全造成了重大威胁,因此本文综述了温度、气体环境、生理生化反应、微生物等几项能够导致鲜切果蔬褐变腐烂、品质下降的重要影响因素;总结了3种生物保鲜剂在鲜切果蔬保鲜中的应用,包括植物类天然保鲜剂、动物类天然保鲜剂和微生物保鲜剂;讨论了生物保鲜剂的不足,并对今后生物保鲜剂的发展进行了展望。%As the requirements of food quality and safety increasing, the preservation technology of fresh-cut fruits and vegetables are developed rapidly. Biological preservatives with safe, efficient and other characteristics becomes the hotspot of fresh-cut fruits and vegetables. Fresh-cut fruits and vegetables are processed with cleaning, trimming, peeling, cutting, and so on. In this process, mechanical damage, physiological metabolism, pathogen infection and other problems can cause decay and quality decline of fresh-cut fruits and vegetables. This has brought a huge loss to the economy and trade of fresh agricultural products, and this is also harmful for human health. This paper reviewed several important factors such as temperature, gas environment, physiological and biochemical reactions, microbial, which could cause browning, decay and poor quality of fresh-cut fruits and vegetables, and the application of biological preservatives on fresh-cut fruits and vegetables, including botanical natural preservatives, animal natural preservatives and microbial natural preservatives. Finally this paper

  10. Study on the Controlling Process of Freezing Point in Fresh-cut Litchi Pulp%鲜切荔枝果肉冰点调节工艺

    Institute of Scientific and Technical Information of China (English)

    吴汶飞; 余小林; 胡卓炎; 周宇

    2011-01-01

    Effects of different freezing point regulators including sucrose, sorbitol and glucose on the freezing point of fresh - cut litchi pulp were evaluated and optimized by response surface methodology. Results showed that the optimal conditions were: sorbitol content 6.24% , glucose content 7.31% and sucrose content 40.93%. Under the optimal conditions, the freezing point of the fresh -cut litchi pulp decreased to -4.15℃ , close to the predicted val ue of -4.13℃. The optimal freezing point of the fresh - cut litchi pulp was reduced by 1.3℃ comparing to the control group.%研究了蔗糖、山梨醇、葡萄糖3种冰点调节剂对降低鲜切荔枝果肉冰点的效果及复配浓度的影响。在单因素实验的基础上,以鲜切荔枝果肉的冰点为响应值,通过响应曲面法建立回归模型,得到山梨醇、葡萄糖、蔗糖3种冰点调节剂的优化复配浓度为:山梨醇6.24%,葡萄糖7.31%,蔗糖40.93%。鲜切荔枝果肉经此优化复配浓度在3cc、浸渍3h处理后,其冰点可降至-4.15℃,与模型预测值(-4.13℃)接近,比未处理果肉的冰点降低了1.3℃。

  11. Do sun- versus shade-grown kiwifruits perform differently upon storage? An overview of fruit maturity and nutraceutical properties of whole and fresh-cut produce.

    Science.gov (United States)

    Landi, Marco; Tardelli, Francesca; Remorini, Damiano; Massai, Rossano; Guidi, Lucia

    2014-05-14

    Fresh-cut produce represents a good method to save about 25% of the kiwifruit not useful to meet the fresh fruit-marketing standard due to improper size and shape. For that reason, fresh-cut kiwifruit has been extensively studied. However, the comprehension of the influence of some aspects of cultivation might further increase the shelf life as well as the nutritional values of that fruit. This study explored the hypothesis that kiwifruits grown fully exposed to sunlight or partially shaded differently perform upon storage as whole fruit and as minimally processed produce. Flesh firmness (FF), total solids soluble (SSC), ascorbate (AAT), flavonoids (TFO), and phenols (TF) contents were evaluated in sliced and whole fruit upon 3 days of storage at 4 °C after 75 days of cold chamber storage at 0 °C. The activities of two enzymes related to the softening process, polygalacturonase (PG) and pectinmethylesterase (PME), were evaluated as well. FF and SSC were constitutively higher in sun-exposed fruit, and those characteristics remained higher during the storage as whole fruit. Greater constitutive content of AAT, TFO, and TP was found in sun-exposed whole fruit, although after cutting the reduction in their content was significantly lower in shaded fruits. PME and PG activities were higher only in whole shaded fruits, whereas no relevant differences occurred after cutting. In summary, sun-exposed fruits were more suitable for the fresh-fruit market, whereas the shaded counterpart displayed a good predisposition for use as fresh-cut produce, maintaining similar fruit maturity properties but higher nutraceutical values when sliced than fruit grown under full sun.

  12. Survival and growth of Cronobacter sakazakii on fresh-cut fruit and the effect of UV-C illumination and electrolyzed water in the reduction of its population.

    Science.gov (United States)

    Santo, David; Graça, Ana; Nunes, Carla; Quintas, Célia

    2016-08-16

    Cronobacter sakazakii, found in foods such as powdered infant formula and plant origin ready-to-eat food, is an opportunistic pathogen to infants, neonates and vulnerable adults. The objective of this study was to monitor the growth of C. sakazakii in fresh-cut 'Royal gala' apple, 'Rocha' pear, and 'Piel de sapo' melon, and the effect of UV-C illumination, acidic electrolyzed water (AEW) and neutral electrolyzed water (NEW) in the reduction of its population. Fresh-cut fruits were inoculated and incubated at different temperatures during 10days while monitoring C. sakazakii. The inhibitory activity of different doses of UV-C (0-10kJ.m(2)), electrolyzed water and sodium hypochlorite (SH) (100ppm chlorine) was evaluated on the fruits inoculated with C. sakazakii. The bacterium showed a significant growth in the fruits at 12 and 20°C, but did not grow at 4°C, despite having survived for 10days. At 8°C, adaptation phases of 0.6-3.9days were estimated in the fruits before exponential growth. The UV-C 7.5 and 10kJ/m(2) produced greater C. sakazakii population decreases (2-2.4logcfu/g) than AEW (1.3-1.8logcfu/g), NEW (1-1.2logcfu/g) and SH (0.8-1.4logcfu/g). The UV-C decontamination system and refrigeration at 4°C, may contribute to the product's safety and quality. The results help better understand the behavior of C. sakazakii on fresh-cut fruit alerting producers of the necessity to respect the high hygienic practices, adequate refrigerating temperature maintenance and caution with the tendency to prolong the validity of this kind of ready-to-eat food. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. 乐平雪梨瓜鲜切保鲜技术研究%Research on Preservation of Fresh-cut Le-ping Melon

    Institute of Scientific and Technical Information of China (English)

    曾荣; 潘炎霞; 林丽超

    2015-01-01

    With fresh-cut Le-ping melon as test materials ,using different blanching temperature and time processing of fresh-cut Le-ping melon,as determined by sensory evaluation,vitamin C content and other indicators,thus obtained the optimum blanching temperature and time combination.On this basis,the combination of the food grade chitosan(1.0%,1.5%)for coating film,got the best fresh method.The results showed that the optimum combination was blanching 60℃2 min,the best combination of blanching+1.5%chitosan worked best.The process could significantly reduce the decline rate of the quality of fresh-cut melon and effectively extend the shelf life.%以鲜切乐平雪梨瓜为试验材料,采用不同的热烫温度和时间处理鲜切雪梨瓜,通过感官评定、VC含量等指标测定,从而得出最佳热烫温度与时间的组合。在此基础上,结合使用食品级的壳聚糖(1.0%、1.5%)进行涂膜处理,得到最佳保鲜方法。结果表明:最佳的处理为60℃热烫2min,同时结合1.5%壳聚糖涂膜保鲜效果最好。通过处理,明显降低了鲜切雪梨瓜品质的下降速度,有效延长了货架期。

  14. Effects of ultraviolet light (UV-C) and heat treatment on the quality of fresh-cut Chokanan mango and Josephine pineapple.

    Science.gov (United States)

    George, Dominic Soloman; Razali, Zuliana; Santhirasegaram, Vicknesha; Somasundram, Chandran

    2015-02-01

    The effects of ultraviolet (UV-C) and medium heat (70 °C) treatments on the quality of fresh-cut Chokanan mango and Josephine pineapple were investigated. Quality attributes included physicochemical properties (pH, titratable acidity, and total soluble solids), ascorbic acid content (vitamin C), antioxidant activity, as well as microbial inactivation. Consumers' acceptance was also investigated through sensory evaluation of the attributes (appearance, texture, aroma and taste). Furthermore, shelf-life study of samples stored at 4 ± 1 °C was conducted for 15 d. The fresh-cut fruits were exposed to UV-C for 0, 15, 30, and 60 min while heat treatments were carried out at 70 °C for 0, 5, 10 and 20 min. Both UV-C and medium heat treatments resulted in no significant changes to the physicochemical attributes of both fruits. The ascorbic acid content of UV-C treated fruits was unaffected; however, medium heat treatment resulted in deterioration of ascorbic acids in both fruits. The antioxidants were enhanced with UV-C treatment which could prove invaluable to consumers. Heat treatments on the other hand resulted in decreased antioxidant activities. Microbial count in both fruits was significantly reduced by both treatments. The shelf life of the fresh-cut fruits were also successfully extended to a maximum of 15 d following treatments. As for consumers' acceptance, UV-C treated fruits were the most accepted as compared to their heat-treated counterparts. The results obtained through this study support the use of UV-C treatment for better retention of quality, effective microbial inactivation and enhancement of health promoting compounds for the benefit of consumers.

  15. Distribution and chemical fate of chlorine dioxide gas during sanitation of tomatoes and cantaloupe

    Science.gov (United States)

    A series of studies was conducted to establish the 1) distribution and chemical fate of 36-ClO2 on tomatoes and cantaloupe; and 2) the magnitude of residues in kilogram quantities of tomatoes and cantaloupe sanitized with a slow-release chlorine dioxide formulation. Tomatoes and cantaloupe were resp...

  16. Effects of postharvest application of 1-MCP and postcutting dip treatment on the quality and nutritional properties of fresh-cut kiwifruit.

    Science.gov (United States)

    Antunes, Maria D C; Dandlen, Susana; Cavaco, Ana M; Miguel, Graça

    2010-05-26

    Consumption of minimally processed fruit and vegetables has increased significantly in the past few years due to the consumers' life style. The aim of this study was to evaluate the effect of treatment with ascorbic acid or calcium chloride on the quality parameters of fresh-cut kiwifruit prepared from fruit previously stored for 3 months, either treated or not treated with 1-methylcyclopropene (1-MCP) before storage. Harvested fruit were treated with 1 microL L(-1) 1-MCP for 20 h at room temperature ( approximately 20 degrees C) (MCP) or had no treatment (C) and were then stored at 0 degrees C. After 3 months, fruit were removed from storage, peeled, and cut longitudinally in quarters, dipped in 2% ascorbic acid (Asc), 2% calcium chloride (Ca), or just water (cont), and kept at 2 degrees C for 8 days. Measurements of firmness, soluble solids content (SSC) ( degrees Brix), color (CIE L*, a*, b*), electrolyte leakage, sugars, organic acids, total phenolics, and antioxidant activity (DPPH and ABTS) were performed at 0, 4, and 8 days. A taste panel was performed on the seventh shelf life day. It was shown that whole MCP-treated kiwifruit kept better than the control through the 3 months storage, this effect being lost through the fresh-cut shelf life period. Furthermore, the postcut dip on 2% CaCl(2) was effective on delaying softening and browning of fresh-cut kiwifruit, which were also the fruit preferred by panelists. Both ascorbic acid and CaCl(2) were effective on preserving or improving nutritional properties (phenolics, ascorbic acid, DPPH, and ABTS) mainly in the first 4 days of shelf life. The CaCl(2) had a further beneficial effect until 8 shelf life days. It is suggested that CaCl(2) is better in keeping overall quality through 8 days of shelf life at 2 degrees C in fresh-cut kiwifruit followed by Asc, and 1-MCP has negligible effect in the conditions of this experiment.

  17. Effect of chitosan molecular weight on the functional properties of chitosan-maltose Maillard reaction products and their application to fresh-cut Typha latifolia L.

    Science.gov (United States)

    Li, Song-Lin; Lin, Jing; Chen, Xiao-Ming

    2014-02-15

    The objective was to evaluate antimicrobial, antioxidant and copper-chelating activities of Maillard reaction products (MRP) prepared from maltose and different molecular weight chitosan, and their effects on preservation of fresh-cut Typha latifolia L. (TLL). LMRP (maltose and low molecular weight chitosan MRP) showed the highest browning and UV absorbance as well as fluorescence intensity. The DPPH radical scavenging activity, reducing power and copper-chelating activity of chitosan-maltose MRP varied depending on the chitosan molecular weight. HMRP (maltose-high molecular weight chitosan MRP) exhibited better effects on inhibiting PPO activity and discoloration, alleviating declines of total soluble solids and ascorbic acid content of fresh-cut TLL. LMRP and MMRP (maltose-medium molecular weight chitosan MRP) effectively decreased weight loss and maintained firmness of TLL, respectively. These results indicated that molecular weight of chitosan had a great impact on the functional properties of chitosan-maltose MRP and their application to be used as a preservative. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. A comparative study on the effectiveness of ozonated water and peracetic acid in the storability of packaged fresh-cut melon.

    Science.gov (United States)

    Botondi, Rinaldo; Moscetti, Roberto; Massantini, Riccardo

    2016-05-01

    Ozonated water and peracetic acid were tested as sanitizers to enhance the storability of fresh-cut melon cubes. Sanitizers were also combined with suitable packaging materials (polypropylene and polylactic acid based plastic films). Fresh-cut melon cubes were stored at 4 °C for up to 7 days. Ozonated water and peracetic acid treatments were given by dipping cubes into 0.8 ppm O3 and 100 ppm Tsunami 100™ solutions, respectively, for 3 min. Both sanitizers exhibited efficiency in reducing the total microbial counts on melon cubes (peracetic acid treatment in combination with polypropylene film packaging, consequently developing off-odors starting from day 3. Strong color changes were noted in cubes stored in polylactic acid packaging after 7 days of storage, affecting the sensory quality of the melon cubes. Sensory evaluation (overall visual quality) indicated loss in flavor in the polypropylene packaging. The overall visual quality started to decline on 3rd day because of the development of translucency.Overall, the use of ozone in combination with polypropylene packaging provided the best solution to maintain the quality of melon cubes for up to 5 days of storage at 4 °C.

  19. Measurement of Multiple Vitamin K Forms in Processed and Fresh-Cut Pork Products in the U.S. Food Supply.

    Science.gov (United States)

    Fu, Xueyan; Shen, Xiaohua; Finnan, Emily G; Haytowitz, David B; Booth, Sarah L

    2016-06-01

    Vitamin K food composition data have historically been limited to plant-based phylloquinone (vitamin K1). The purpose of this study was to expand analysis of vitamin K to animal products and to measure phylloquinone and 10 forms of menaquinones (vitamin K2) in processed and fresh-cut pork products. Nationally representative samples of processed pork products (n = 28) were obtained through USDA's National Food and Nutrition Analysis Program, and fresh pork (six cuts; n = 5 per cut) and bacon (n = 4) were purchased from local retail outlets. All samples were analyzed by high-performance liquid chromatography (phylloquinone and menaquinone-4) and atmospheric-pressure chemical ionization-liquid chromatography-mass spectrometry (menaquinone-5 to menaquinone-13). Although low in phylloquinone (processed pork products and fresh pork cuts contained menaquinone-4, menaquinone-10, and menaquinone-11 (range: [35.1 ± 11.0]-[534 ± 89.0] μg of menaquinones per 100 g). The total menaquinone contents of processed pork products were correlated with fat contents (r = 0.935). In summary, processed and fresh-cut pork products are a rich dietary source of menaquinones that are currently unaccounted for in assessment of vitamin K in the food supply.

  20. Interactions between sanitizers and packaging gas compositions and their effects on the safety and quality of fresh-cut onions (Allium cepa L.).

    Science.gov (United States)

    Page, Natalie; González-Buesa, Jaime; Ryser, Elliot T; Harte, Janice; Almenar, Eva

    2016-02-01

    Onions are one of the most widely utilized vegetables worldwide, with demand for fresh-cut onions steadily increasing. Due to heightened safety concerns and consumer demand, the implications of sanitizing and packaging on fresh-cut onion safety and quality need to be better understood. The objective of this study was to investigate the effect of produce sanitizers, in-package atmospheres, and their interactions on the growth of Salmonella Typhimurium, mesophilic aerobic bacteria, yeast and mold, and the physico-chemical quality of diced onions to determine the best sanitizer and in-package atmosphere combination for both safety and quality. Diced onions were inoculated or not with S. Typhimurium, sanitized in sodium hypochlorite, peroxyacetic acid, or liquid chlorine dioxide, and then packaged in either polylactic acid bags containing superatmospheric O2, elevated CO2/reduced O2, or air, or in polyethylene terephthalate snap-fit containers. Throughout 14 days of storage at 7 °C, packaged diced onions were assessed for their safety (S. Typhimurium), and quality (mesophilic aerobic bacteria, yeasts and molds, physico-chemical analyses, and descriptive and consumer acceptance sensory panels). While sanitizer affected (Ppackage atmosphere had a significant (Ppackage atmosphere combination for enhancing the safety and quality of packaged diced onions. In addition, this combination led to diced onions acceptable for purchase after 2 weeks of storage by trained and consumer panels.

  1. Enzymatic Browning Controling of Fresh Cut-lotus Roots%鲜切莲藕酶促褐变控制的研究

    Institute of Scientific and Technical Information of China (English)

    郝亚勤

    2014-01-01

    选择柠檬酸(CA)、D-异抗坏血酸钠(D-EA)、乙二胺四乙酸二钠(EDTA-2Na)3种对莲藕(Neulmbo nucifera Gaerth)多酚氧化酶(Polyphenol oxidase,PPO)活性抑制率较高的抑制剂,作为鲜切莲藕酶促褐变抑制剂,研究3种抑制剂及其组合对抑制鲜切莲藕酶促褐变的效应。结果表明,3种褐变抑制剂最佳组合用量为2.5 g / L CA+1.5 g / L D-EA+1.5 g / L EDTA-2Na。%The high inhibitors including Citric acid (CA), Sodium D-isoascorbate (D-EA) and Edathamil disodium (EDTA-2Na) of activity of polyphenol oxidase of lotus root Neulmbo nucifera Gaerth were used as the enzymatic browning inhibitors of fresh-cut lotus roots. The effects of the inhibitors and its combination on the inhibition of enzymatic browning of fresh cut lotus root were studied. The results showed that the optimal dosage of combination of this three enzymatic browning inhibitors was 2. 5g/LCA+1. 5g/LD-EA+1. 5g/LEDTA-2Na.

  2. 405 ± 5 nm light emitting diode illumination causes photodynamic inactivation of Salmonella spp. on fresh-cut papaya without deterioration.

    Science.gov (United States)

    Kim, Min-Jeong; Bang, Woo Suk; Yuk, Hyun-Gyun

    2017-04-01

    This study evaluated the antibacterial effect of 405 ± 5 nm light emitting diode (LED) illumination against four Salmonella serovars on fresh-cut papaya and on fruit quality at various storage temperatures. To determine the antibacterial mechanism of LED illumination at 0.9 kJ/cm(2), oxidative damage to DNA and membrane lipids of Salmonella in phosphate-buffered saline solution was measured. The populations of Salmonella on cut fruits were significantly (P fruits. Levels of bacterial DNA oxidation significantly increased, whereas lipid peroxidation in bacterial membrane was not observed, suggesting that DNA oxidation contributes to photodynamic inactivation by LED illumination. LED illumination did not adversely affect the physicochemical and nutritional qualities of cut papaya, regardless of storage temperature. These results indicate that a food chiller equipped with 405 ± 5 nm LEDs can preserve fresh-cut papayas in retail stores without deterioration, minimizing the risk of salmonellosis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Hydrogen sulfide prolongs postharvest storage of fresh-cut pears (Pyrus pyrifolia by alleviation of oxidative damage and inhibition of fungal growth.

    Directory of Open Access Journals (Sweden)

    Kang-Di Hu

    Full Text Available Hydrogen sulfide (H2S has proved to be a multifunctional signaling molecule in plants and animals. Here, we investigated the role of H2S in the decay of fresh-cut pears (Pyrus pyrifolia. H2S gas released by sodium hydrosulfide (NaHS prolonged the shelf life of fresh-cut pear slices in a dose-dependent manner. Moreover, H2S maintained higher levels of reducing sugar and soluble protein in pear slices. H2S significantly reduced the accumulation of hydrogen peroxide (H2O2, superoxide radicals (•O2(- and malondialdehyde (MDA. Further investigation showed that H2S fumigation up-regulated the activities of antioxidant enzymes ascorbate peroxidase (APX, catalase (CAT, and guaiacol peroxidase (POD, while it down-regulated those of lipoxygenase (LOX, phenylalanine ammonia lyase (PAL and polyphenol oxidase (PPO. Furthermore, H2S fumigation effectively inhibited the growth of two fungal pathogens of pear, Aspergillus niger and Penicillium expansum, suggesting that H2S can be developed as an effective fungicide for postharvest storage. The present study implies that H2S is involved in prolonging postharvest storage of pears by acting as an antioxidant and fungicide.

  4. Arsenic Uptake by Muskmelon (Cucumis melo) Plants from Contaminated Water.

    Science.gov (United States)

    Hettick, Bryan E; Cañas-Carrell, Jaclyn E; Martin, Kirt; French, Amanda D; Klein, David M

    2016-09-01

    Arsenic is a carcinogenic element that occurs naturally in the environment. High levels of arsenic are found in water in some parts of the world, including Texas. The aims of this study were to determine the distribution of arsenic in muskmelon (Cucumis melo) plants accumulated from arsenic spiked water and to observe effects on plant biomass. Plants were grown and irrigated using water spiked with variable concentrations of arsenic. Inductively coupled plasma mass spectrometry was used to quantify arsenic in different parts of the plant and fruit. Under all conditions tested in this study, the highest concentrations of arsenic were found in the leaves, soil, and roots. Arsenic in the water had no significant effect on plant biomass. Fruits analyzed in this study had arsenic concentrations of 101 μg/kg or less. Consuming these fruits would result in less arsenic exposure than drinking water at recommended levels.

  5. The Effect of Isabgol (Plantago psyllium Mucilage and Shiraz Thyme Essential Oils on Microbial Load and Improving Shelf Life of Fresh-Cut Carrot

    Directory of Open Access Journals (Sweden)

    M. Azizi

    2016-02-01

    Full Text Available Introduction: Fresh-cut produce graduated to retail during the1990s, especially for lettuce, cabbage, carrots and other similar vegetables. The high microbial loads of these products after harvest can be substantially reduced through a cleaning in flowing chlorinated water and adistribution under ensured controlledrefrigeration. Therefore, a good number of convenient ready-to-use greens were launched to the market in the past decade. Nowadays, theuse of this technology to achieve similar results in fruit products is one of the most challengingtargets for processors. However, there is anumber of issues that still need to beovercomebeforefresh-cut fruit commodities can be sparked off to anoutstanding position in the segment of lightly-treatedrefrigerated foods. The importance of freshly cut products increases day by day. Tissue and cell rupture leads to a decrease in the shelf life of these products. On the other hand, these products due to increased enzyme activity, respiration rate and microbiological considerations that affect the health of these productsrequires highly attention.To increase the shelf life of the products and prevent undesirable changes in cut slices of fruit or vegetables a coating on the surface of these products has been suggested. Mucilages and essential oils of herbs are natural compounds that can be used to create such covers. The advantages of these coatings are their bactericidal effect, maintenanceof pleasant taste and other physical and chemical characteristics of the product and even decrease of environmental pollution. In this research, the effect of natural compounds such as Zataria multiflora essential oil (EO and Plantagopsyllium mucilage on storage life and microbial load of fresh cut carrot was studied. Materials and Methods: The research was conducted in two separate experiments on fresh-cut carrot: In the first experiment, the effect of different concentrations of Plantago psyllium mucilage (0,100, 200, and

  6. Use of UV-C treatments to maintain quality and extend the shelf life of green fresh-cut bell pepper (Capsicum annuum L.).

    Science.gov (United States)

    Rodoni, Luis M; Concellón, Analía; Chaves, Alicia R; Vicente, Ariel R

    2012-06-01

    The objective of this work was to select a Ultraviolet-C (UV-C) treatment for fresh-cut mature green bell pepper, and to evaluate the effect of its combination with refrigeration on quality maintenance. Bell pepper sticks were treated with 0, 3, 10, or 20 kJ/m² UV-C in the outer (O), inner (I), or both sides of the pericarp (I/O) and stored for 8 d at 10 °C. During the first 5 d of storage, all UV-C treatments reduced deterioration as compared to the control. The treatment with 20 kJ/m² I/O was the most effective to reduce deterioration, and was used for further evaluations. In a second group of experiments, mature green bell pepper sticks were treated with 20 kJ/m² I/O, stored at 5 °C for 7 or 12 d and assessed for physical and chemical analysis, and microbiological quality. UV-C-treated fruit showed lower exudates and shriveling than the control. UV exposure also reduced decay, tissue damage, and electrolyte leakage. After 12 d at 5 °C, UV-C irradiated peppers remained firmer and had higher resistance to deformation than the control. The UV-C treatments also reduced weight loss and pectin solubilization. UV-C exposure decreased the counts of mesophile bacteria and molds, and did not affect acidity or sugars. UV-C-treated fruit stored for 0 or 7 d at 5 °C did not show major differences in antioxidants from the control as measured against DPPH(•) or ABTS(•)⁺ radicals. Results suggest that UV-C exposure is useful to maintain quality of refrigerated fresh-cut green pepper. Exposure to UV-C radiation before packing and refrigeration could be a useful nonchemical alternative to maintain quality and reduce postharvest losses in the fresh-cut industry. © 2012 Institute of Food Technologists®

  7. Avaliação da qualidade de mangas 'Tommy Atkins' minimamente processadas Quality evaluation of fresh-cut 'Tommy Atkins' mangoes

    Directory of Open Access Journals (Sweden)

    Brígida Monteiro Vilas Boas

    2004-12-01

    Full Text Available Visto que a popularidade de frutas e hortaliças minimamente processadas tem aumentado nos últimos anos devido aos aspectos de conveniência e qualidade, este trabalho teve por objetivo avaliar o efeito do ácido cítrico 1%, ácido ascórbico 1% e cloreto de cálcio 1% na conservação de mangas 'Tommy Atkins' minimamente processadas, armazenadas sob atmosfera modificada ativa (5% O2 + 5% CO2 e refrigeração por 12 dias. Foram realizadas as seguintes análises: acidez titulável, pH, sólidos solúveis totais, açúcares solúveis totais, vitamina C total, análise sensorial (sabor e análises microbiológicas (contagem de fungos filamentosos e leveduras e coliformes a 35 e 45ºC. Pode-se concluir que os tratamentos com ácido cítrico 1%, ácido ascórbico 1% e CaCl2 1% não influenciam na vida de prateleira das mangas 'Tommy Atkins' minimamente processadas. De acordo com a análise sensorial e microbiológica, a vida útil é de 12 dias a 5ºC.Since the popularity of fresh-cut fruits and vegetables has increased lately, due to the convenience and quality aspects, chemical modifications were investigated, in addition to sensory and microbiological aspects of fresh-cut the 'Tommy Atkins' mangoes were treated with 1% citric acid, 1% ascorbic acid and 1% calcium chloride stored under active modified atmospheres (5% O2 + 5% CO2 and refrigerated for 12 days. The following analyses were done: titratable acidity, pH, total soluble solids, total soluble sugars, C vitamin, sensory analysis (taste and microbiological analyses (filamentous fungus and yeast counting and coliforms at 35 e 45ºC. It was concluded that the treatments with 1% citric acid, 1% ascorbic acid and 1% CaCl2 didn't influence the shelf-life of the fresh-cut 'Tommy Atkins' mangoes. According to the sensory and microbiological analyses the useful life is 12 days at 5ºC.

  8. Efeito de diferentes temperaturas na qualidade de mandioquinha-salsa minimamente processada Effect of different temperatures on the quality of fresh-cut Peruvian carrot

    Directory of Open Access Journals (Sweden)

    Elisângela Elena Nunes

    2010-09-01

    Full Text Available O objetivo do presente trabalho foi avaliar a vida útil de mandioquinha-salsa 'Amarela de Senador Amaral' minimamente processada e armazenada em três temperaturas de armazenamento. As raízes foram descascadas manualmente, fatiadas (±1 cm de espessura, imersas em solução de dicloro isocianurato de sódio 100 mg L-1 por 15 minutos e acondicionadas em embalagem rígida de polipropileno (15 x 11,5 x 4,5 cm. As embalagens, contendo cerca de 150 g de raízes minimamente processadas, foram armazenadas a 0±1ºC, 5±1ºC ou 10±1ºC durante 15 dias, sendo realizadas análises a cada 3 dias. O delineamento experimental foi inteiramente casualizado em fatorial 3 x 6, sendo 3 temperaturas de armazenamento e 6 períodos de armazenamento, com 3 repetições. O armazenamento a 0ºC determinou, ao longo do armazenamento, aumento nos valores de L* e b*, menores valores de a*, menor atividade da peroxidase, polifenoloxidase, poligalacturonase, solubilização péctica e taxa respiratória, sendo a temperatura mais indicada para o armazenamento da mandioquinha-salsa 'Amarela de Senador Amaral' minimamente processada.The shelf life of fresh-cut Peruvian carrots 'Amarela de Senador Amaral', stored under three temperatures, was evaluated. The roots were peeled manually, sliced (±1 cm thick, immersed in a solution of sodium dichloroisocyanurate 100 mg L-1 during 15 minutes and packed in rigid polypropylene package (15 x 11.5 x 4.5 cm. The packages containing around 150 g of fresh cut roots were stored under 0±1ºC, 5±1ºC or 10±1ºC during 15 days. The analyses were performed every 3 days. The experimental design was completely randomized in a 3 x 6 factorial (3 storage temperature and 6 periods of storage, with three replicates. The storage at 0ºC provided higher L* and b* values, lower a* values, lower peroxidase, polyphenoloxidase and polygalacturonase activity, pectic solubilization and respiration rate. This temperature is the most proper for the

  9. Grafting Helps Improve Photosynthesis and Carbohydrate Metabolism in Leaves of Muskmelon

    Directory of Open Access Journals (Sweden)

    Yi-Fei Liu, Hong-Yan Qi, Chun-Ming Bai, Ming-Fang Qi, Chuan-Qiang Xu, Jing-Hong Hao, Yan Li, Tian-Lai Li

    2011-01-01

    Full Text Available The most important quality for muskmelon (Cucumis melo L. is their sweetness which is closely related to the soluble sugars content. Leaves are the main photosynthetic organs in plants and thus the source of sugar accumulation in fruits since sugars are translocated from leaves to fruits. The effects of grafting muskmelon on two different inter-specific (Cucurbita maxima×C. moschata rootstocks was investigated with respect to photosynthesis and carbohydrate metabolism. Grafting Zhongmi1 muskmelon on RibenStrong (GR or Shengzhen1 (GS rootstocks increased chlorophyll a, chlorophyll b and chlorophyll a+b content and the leaf area in middle and late developmental stages of the plant compared to the ungrafted Zhongmi1 check (CK. Grafting enhanced the net photosynthesis rate, the stomatal conductance, concentration of intercellular CO2 and transpiration rate. Grafting influenced carbohydrates contents by changing carbohydrate metabolic enzymes activities which was observed as an increase in acid invertase and neutral invertase activity in the functional leaves during the early and middle developmental stages compared to CK. Grafting improved sucrose phosphate synthase and stachyose synthase activities in middle and late developmental stages, thus translocation of sugars (such as sucrose, raffinose and stachyose in GR and GS leaves were significantly enhanced. However, compared with CK, translocation of more sugars in grafted plants did not exert feedback inhibition on photosynthesis. Our results indicate that grafting muskmelon on inter-specific rootstocks enhances photosynthesis and translocation of sugars in muskmelon leaves.

  10. [Effects of elevated rhizosphere CO2 concentration on the photosynthetic characteristics, yield, and quality of muskmelon].

    Science.gov (United States)

    Liu, Yi-Ling; Sun, Zhou-Ping; Li, Tian-Lai; Gu, Feng-Ying; He, Yu

    2013-10-01

    By using aeroponics culture system, this paper studied the effects of elevated rhizosphere CO2 concentration on the leaf photosynthesis and the fruit yield and quality of muskmelon during its anthesis-fruiting period. In the fruit development period of muskmelon, as compared with those in the control (350 microL CO2 x L (-1)), the leaf chlorophyll content, net photosynthetic rate (Pn), stomatal conductance (Gs), intercellular CO2 concentration (Ci), and the maximal photochemical efficiency of PS II (Fv/Fm) in treatments 2500 and 5000 microL CO2 x L(-1) decreased to some extents, but the stomatal limitation value (Ls) increased significantly, and the variation amplitudes were larger in treatment 5000 microL CO2 x L(-1) than in treatment 2500 microL CO2 x L(-1). Under the effects of elevated rhizosphere CO2 concentration, the fruit yield per plant and the Vc and soluble sugar contents in fruits decreased markedly, while the fruit organic acid content was in adverse. It was suggested that when the rhizosphere CO2 concentration of muskmelon during its anthesis-fruiting period reached to 2500 microL x L(-1), the leaf photosynthesis and fruit development of muskmelon would be depressed obviously, which would result in the decrease of fruit yield and quality of muskmelon.

  11. Fungicides for organic cantaloupe production in Oklahoma: An initial assessment

    Science.gov (United States)

    Fungicides that are potentially useful in organic production were evaluated for foliar disease control in cantaloupe (Cucumis melo L. var. reticulates ’Israeli’) during 2009 at Lane, Oklahoma. Milstop (85% potassium bicarbonate), Neem oil, Bonide liquid copper (10% copper octanoate), Serenade (QST ...

  12. Pollen collection and honey bee forager distribution in cantaloupe

    Science.gov (United States)

    Honey bee (Apis mellifera, L.) pollen collection and forager distribution were examined during the summer of 2002 in a cantaloupe (Cucumis melo, L., Cruiser cv.) field provided with plastic mulch and drip irrigation. The experimental site was located near the INIFAP Campo Experimental La Laguna, Ma...

  13. Vision Loss following Intraocular Listeriosis Associated with Contaminated Cantaloupe

    Directory of Open Access Journals (Sweden)

    Mam Ibraheem

    2013-06-01

    Full Text Available Intraocular listeriosis, a rare manifestation of invasive listeriosis, has a poor visual prognosis. We report an intraocular listeriosis case related to a multistate outbreak associated with contaminated cantaloupe. Increasing awareness of rare listeriosis presentations might facilitate timely diagnosis and treatment, and case reporting can clarify medical and epidemiologic aspects of listeriosis.

  14. Vision Loss following Intraocular Listeriosis Associated with Contaminated Cantaloupe

    OpenAIRE

    Mam Ibraheem; Sushma Vance; Jackson, Kelly A.; Paul Ettestad; Chad Smelser; Benjamin Silk

    2013-01-01

    Intraocular listeriosis, a rare manifestation of invasive listeriosis, has a poor visual prognosis. We report an intraocular listeriosis case related to a multistate outbreak associated with contaminated cantaloupe. Increasing awareness of rare listeriosis presentations might facilitate timely diagnosis and treatment, and case reporting can clarify medical and epidemiologic aspects of listeriosis.

  15. Modificações sensoriais em cenoura minimamente processada e armazenada sob refrigeração Sensory modifications of fresh cut carrots stored under refrigeration

    Directory of Open Access Journals (Sweden)

    Josane Maria Resende

    2004-03-01

    Full Text Available Foram avaliadas as modificações sensoriais em cenoura minimamente processada em dois tipos de cortes durante o armazenamento sob refrigeração. Semanalmente avaliou-se a aparência, a cor, o aroma, o sabor e a textura de cenouras cv. Nantes, minimamente processadas, acondicionadas em potes de polietileno tereftalato (PET e armazenadas a 7ºC, por 14 dias. Para definir a freqüência de consumo e preferência pelo tipo de corte, amostras do produto foram apresentadas ao público e os resultados foram anotados em porcentagem em relação ao número total de pessoas consultadas. Com o decorrer do armazenamento houve redução nos escores para a aparência e a cor, enquanto que o sabor e a textura melhoraram em ambos os cortes. Cenouras raladas apresentaram melhor cor e aparência em relação à cenoura cortada em rodelas, entretanto o sabor e a textura foram melhores para cenouras em rodelas. As cenouras raladas são as mais indicadas para o consumo uma vez que a aparência é o atributo que mais causa impacto na escolha pelo consumidor e dentro desta a cor é a característica mais relevante. A freqüência de consumo deste tipo de produto esta aumentando gradativamente e em relação à preferência pelo tipo de corte, o consumidor optou pela cenoura ralada pela sua maior praticidade e versatilidade de uso.Sensory modifications were evaluated in carrots cv Nantes lightly processed in two kinds of cut (grated and sliced during the storage under refrigeration. Fresh cut carrots were packed in polyethylene tereftalato (PET boxes and stored at 7ºC for 14 days. The carrot's appearance, color, aroma, flavor and texture were evaluated weekly. To obtain the frequency of consumption and preference of kind of cut, samples were offered to people to try. During the storage of both kinds of cut, a reduction in scores for appearance and color occurred, while flavor and texture scores were improved. Fresh cut carrots in the grated form presented better

  16. 鲜切果蔬微生物污染及控制研究进展%Research progress in control and microbial infection of fresh-cut fruits and vegetables

    Institute of Scientific and Technical Information of China (English)

    吴晓彬; 胡文忠; 刘程惠; 韩巍巍

    2011-01-01

    Microbial infection is one of the most important factors influencing quality of fresh-cut fruits and vegetables. In this paper,the sources and species of microbial,which effect on physiology of fresh-cut fruits and vegetables,were reviewed. The control methods on microbial of fresh-cut fruits and vegetables were introduced at home and abroad.%微生物侵染是影响鲜切果蔬品质的重要因素之一.本文概述了鲜切果蔬中微生物的污染来源、种类及其对鲜切果蔬组织生理的影响,并对国内外微生物的控制方法进行了介绍.

  17. Methodology for modeling the disinfection efficiency of fresh-cut leafy vegetables wash water applied on peracetic acid combined with lactic acid.

    Science.gov (United States)

    Van Haute, S; López-Gálvez, F; Gómez-López, V M; Eriksson, Markus; Devlieghere, F; Allende, Ana; Sampers, I

    2015-09-02

    A methodology to i) assess the feasibility of water disinfection in fresh-cut leafy greens wash water and ii) to compare the disinfectant efficiency of water disinfectants was defined and applied for a combination of peracetic acid (PAA) and lactic acid (LA) and comparison with free chlorine was made. Standardized process water, a watery suspension of iceberg lettuce, was used for the experiments. First, the combination of PAA+LA was evaluated for water recycling. In this case disinfectant was added to standardized process water inoculated with Escherichia coli (E. coli) O157 (6logCFU/mL). Regression models were constructed based on the batch inactivation data and validated in industrial process water obtained from fresh-cut leafy green processing plants. The UV254(F) was the best indicator for PAA decay and as such for the E. coli O157 inactivation with PAA+LA. The disinfection efficiency of PAA+LA increased with decreasing pH. Furthermore, PAA+LA efficacy was assessed as a process water disinfectant to be used within the washing tank, using a dynamic washing process with continuous influx of E. coli O157 and organic matter in the washing tank. The process water contamination in the dynamic process was adequately estimated by the developed model that assumed that knowledge of the disinfectant residual was sufficient to estimate the microbial contamination, regardless the physicochemical load. Based on the obtained results, PAA+LA seems to be better suited than chlorine for disinfecting process wash water with a high organic load but a higher disinfectant residual is necessary due to the slower E. coli O157 inactivation kinetics when compared to chlorine.

  18. Study on Color Protective Treatment of Fresh-cut Yacon%鲜切雪莲果护色效果的研究

    Institute of Scientific and Technical Information of China (English)

    蔡文韬; 夏延斌

    2012-01-01

    研究不同褐变抑制剂对鲜切雪莲果护色效果,通过正交试验并运用多指标试验设计综合加权评分法对多种抑制剂护色效果的进行综合选优.试验结果表明:采用0.5%柠檬酸+0.5%抗坏血酸+0.05‰焦亚硫酸钠浸泡10min的复合处理,试验综合加权评分值为97.6414.雪莲果的PPO活性为0.007、褐变度为3.62、感官品质为7,在10d内抑制褐变效果最好.%The effects of different inhibitors on fresh-cut yacon were studied. It was optimized comprehensively for a variety of protect color inhibitors through orthogonal experiment and using multi-index experimental design and weighted score. The results showed that the optimum combination treatment was 0.5% citric acid +0.5%ascorbic acid +0.05%o sodium pyrosulfite, and the optimum time for the fresh-cut yacon dipping in the solution was 10 min. After the treatment, the value of fi was of 97.6414; the PPO activity was of 0.007; BD value was of 3.62; the quality of appearance was of 7; and the best color protective effect was found within l0d.

  19. Modelling growth of Escherichia coli O157:H7 in fresh-cut lettuce submitted to commercial process conditions: chlorine washing and modified atmosphere packaging.

    Science.gov (United States)

    Posada-Izquierdo, Guiomar D; Pérez-Rodríguez, Fernando; López-Gálvez, Francisco; Allende, Ana; Selma, María V; Gil, María I; Zurera, Gonzalo

    2013-04-01

    Fresh-cut iceberg lettuce inoculated with Escherichia coli O157:H7 was submitted to chlorine washing (150 mg/mL) and modified atmosphere packaging on laboratory scale. Populations of E. coli O157:H7 were assessed in fresh-cut lettuce stored at 4, 8, 13 and 16 °C using 6-8 replicates in each analysis point in order to capture experimental variability. The pathogen was able to grow at temperatures ≥8 °C, although at low temperatures, growth data presented a high variability between replicates. Indeed, at 8 °C after 15 days, some replicates did not show growth while other replicates did present an increase. A growth primary model was fitted to the raw growth data to estimate lag time and maximum growth rate. The prediction and confidence bands for the fitted growth models were estimated based on Monte-Carlo method. The estimated maximum growth rates (log cfu/day) corresponded to 0.14 (95% CI: 0.06-0.31), 0.55 (95% CI: 0.17-1.20) and 1.43 (95% CI: 0.82-2.15) for 8, 13 and 16 °C, respectively. A square-root secondary model was satisfactorily derived from the estimated growth rates (R(2) > 0.80; Bf = 0.97; Af = 1.46). Predictive models and data obtained in this study are intended to improve quantitative risk assessment studies for E. coli O157:H7 in leafy green products. Copyright © 2012. Published by Elsevier Ltd.

  20. Combined Effect of Thermosonication and Slightly Acidic Electrolyzed Water to Reduce Foodborne Pathogens and Spoilage Microorganisms on Fresh-cut Kale.

    Science.gov (United States)

    Mansur, Ahmad Rois; Oh, Deog-Hwan

    2015-06-01

    This study evaluated the efficacy of individual treatments (thermosonication [TS+DW] and slightly acidic electrolyzed water [SAcEW]) and their combination on reducing Escherichia coli O157:H7, Listeria monocytogenes, and spoilage microorganisms (total bacterial counts [TBC], Enterobacteriaceae, Pseudomonas spp., and yeast and mold counts [YMC]) on fresh-cut kale. For comparison, the antimicrobial efficacies of sodium chlorite (SC; 100 mg/L) and sodium hypochlorite (SH; 100 mg/L) were also evaluated. Each 10 g sample of kale leaves was inoculated to contain approximately 6 log CFU/g of E. coli O157:H7 or L. monocytogenes. Each inoculated or uninoculated samples was then dip treated with deionized water (DW; control), TS+DW, and SAcEW at various treatment conditions (temperature, physicochemical properties, and time) to assess the efficacy of each individual treatment. The efficacy of TS+DW or SAcEW was enhanced at 40 °C for 3 min, with an acoustic energy density of 400 W/L for TS+DW and available chlorine concentration of 5 mg/L for SAcEW. At 40 °C for 3 min, combined treatment of thermosonication 400 W/L and SAcEW 5 mg/L (TS+SAcEW) was more effective in reducing microorganisms compared to the individual treatments (SAcEW, SC, SH, and TS+DW) and combined treatments (TS+SC and TS+SH), which significantly (P 3.24 log CFU/g, respectively. The results suggest that the combined treatment of TS+SAcEW has the potential as a decontamination process in fresh-cut industry.

  1. Chloroxyanion Residue Quantification in Cantaloupes Treated with Chlorine Dioxide Gas.

    Science.gov (United States)

    Kaur, Simran; Smith, David J; Morgan, Mark T

    2015-09-01

    Previous studies show that treatment of cantaloupes with chlorine dioxide (ClO2) gas at 5 mg/liter for 10 min results in a significant reduction (P < 0.05) in initial microflora, an increase in shelf life without any alteration in color, and a 4.6- and 4.3-log reduction of Escherichia coli O157:H7 and Listeria monocytogenes, respectively. However, this treatment could result in the presence of chloroxyanion residues, such as chloride (Cl(-)), chlorite (ClO2(-)), chlorate (ClO3(-)), and perchlorate (ClO4(-)), which, apart from chloride, are a toxicity concern. Radiolabeled chlorine dioxide ((36)ClO2) gas was used to describe the identity and distribution of chloroxyanion residues in or on cantaloupe subsequent to fumigation with ClO2 gas at a mean concentration of 5.1 ± 0.7 mg/liter for 10 min. Each treated cantaloupe was separated into rind, flesh, and mixed (rind and flesh) sections, which were blended and centrifuged to give the corresponding sera fractions. Radioactivity detected, ratio of radioactivity to mass of chlorite in initial ClO2 gas generation reaction, and distribution of chloroxyanions in serum samples were used to calculate residue concentrations in flesh, rind, and mixed samples. Anions detected on the cantaloupe were Cl(-) (∼ 90%) and ClO3(-) (∼ 10%), located primarily in the rind (19.3 ± 8.0 μg of Cl(-)/g of rind and 4.8 ± 2.3 μg of ClO3(-)/g of rind, n = 6). Cantaloupe flesh (∼ 200 g) directly exposed to(36)ClO2 gas treatment showed the presence of only Cl(-) residues (8.1 ± 1.0 μg of Cl(-)/g of flesh, n = 3). Results indicate chloroxyanion residues Cl(-) and ClO3(-) are only present on the rind of whole cantaloupes treated with ClO2 gas. However during cutting, residues may be transferred to the fruit flesh. Because Cl(-) is not toxic, only ClO3(-) would be a toxicity concern, but the levels transferred from rind to flesh are very low. In the case of fruit flesh directly exposed to ClO2 gas, only nontoxic Cl(-) was detected. This

  2. Quality of fresh-cut avocado (Persea americana Mill. stored under different temperatures Qualidade de abacates (Persea americana Mill. minimally processados armazenados sob diferentes temperaturas

    Directory of Open Access Journals (Sweden)

    Ana Carla Marques Pinheiro

    2009-08-01

    Full Text Available The goal of this work was to evaluate the effect of different storage temperatures on the quality maintenance of fresh-cut 'Fortuna' avocado (Persea americana Mill.. The fruit was selected, washed and sanitized with sodium hypochlorite solution (190 ppm total residual chlorinee for 15 minutes. After that, the tip was cut and the fruit was also cut in halves, peeled and the pit removed, manually. Then the halves were immersed in 0.5% calcium chlorite + 0.5% cysteine solution for 2 minutes, to avoid darkening and packed in rigid plastic covered with 20 micrometer thick plastic wrap (PVC film with a permeability to O2, CO2 and water vapor of 15,000, 80,000 and 390 cm³/m²/day, respectively. The product was stored under 3 different temperatures 0, 5, 10ºC and evaluated at 5 different storege periods of 0, 2, 3, 5 and 6 days, in a randomized design in a 3x5 factorial. The storage of fresh-cut avocado at 5ºC is the best alternative because it determines better maintenance of quality of the avocado. These presented lower darkening of pulp, better scores for appearance and acceptability, lower softening and polyphenoloxidase activity, in comparison to those stored at 0 and 10ºC. The fresh-cut avocados stored at 5ºC presented a shelf life of 5 days, based, mainly on, appearance, score 7.3, sited between the concepts "like moderately" and "like very much" on a hedonic scale of 9 points and 86% of acceptability, at the end of 5 days of storage.Objetivou-se avaliar o efeito de diferentes temperaturas de armazenamento na manutenção da qualidade de abacates 'Fortuna' (Persea americana Mill. minimally processados. Os frutos foram lavados e sanificados em solução de hipoclorito de sódio (190 ppm de cloro residual total por 15 minutos. Posteriormente, efetuou-se a retirada da extremidade onde se insere o pedúnculo, o corte em metades, retirada do caroço e casca, manualmente. Em seguida, as metades foram imersas em solução com cloreto de cálcio 0

  3. Efeito do tipo de corte e de sanificantes no escurecimento de pequi minimamente processado Effect of cutting type and sanitizers on the browning of fresh cut peki fruit

    Directory of Open Access Journals (Sweden)

    Luiz José Rodrigues

    2011-06-01

    Full Text Available Conduziu-se este trabalho, com o objetivo de avaliar a influência dos sanificantes hipoclorito de sódio (NaClO e de peróxido de hidrogênio (H2O2 em diferentes concentrações sobre a vida de prateleira de pequi (Caryocar brasilense Cambess. submetido a dois tipos de processamento mínimo: "caroço fatiado" e "caroço inteiro", e armazenados a 6 ± 1° C e 90 a 95% UR, durante 15 dias. O experimento foi conduzido em delineamento inteiramente casualizado, disposto em um fatorial 2 x 6 x 5, ou seja, 2 tipos de processamento (caroços "fatiados" e "inteiros", 6 tempos (0h, 3, 6, 9, 12, 15 dias e 5 tratamentos (controle, NaClO 50 ppm, NaClO 100 ppm, H2O2 4% e H2O2 6%, com 3 repetições. A cada três dias foram realizadas as análises: vitamina C, polifenoloxidase, peroxidase e cor (CIE L*a*b*. O pequi minimamente processado apresentou decréscimo nos teores de vitamina C ao longo do armazenamento. O caroço fatiado mostrou-se com maior atividade da enzima polifenoloxidase em relação ao inteiro. A interação significativa entre o corte, o sanificante e o tempo ocorreu para a variável peroxidase, tendo sido observado para o caroço fatiado tratado com os sanificantes H2O2 4 e 6% maior atividade dessa enzima. Observou-se a redução do valor de L*, durante o armazenamento do pequi minimamente processado, independente do sanificante utilizado, ocasionado pelo escurecimento do produto.The objective of the present work was to evaluate the influence of the sanitizers sodium hypochlorite (NaClO 50 and 100 ppm and 4% and 6%, hydrogen peroxide (H2O2 on the shelf life of fresh cut peki fruit (Caryocar brasilense Cambess. submitted to two sorts of processing: "sliced stone" and whole stone", stored at 6 ± 1° C and 90 to 95% of RH for 15 days. The analyses were performed every three days. The experiment was conducted in a completely randomized design arranged by a 2 x 6 x 5 factorial, i.e. 2 sorts of processing ("sliced and whole stones", 6 times (0h

  4. Qualidade e vida útil de pequi minimamente processado armazenado sob atmosfera modificada Quality and shelf life of fresh-cut peki stored under modified atmosphere

    Directory of Open Access Journals (Sweden)

    Éllen Cristina de Souza

    2007-12-01

    Full Text Available Objetivou-se neste trabalho avaliar a eficiência do uso de atmosfera modificada passiva e ativa na manutenção da qualidade e prolongamento da vida útil de pequi minimamente processado armazenado a 5ºC, por 12 dias, através de avaliações fisiológicas, físicas, físico-químicas e químicas. Os pequis foram lavados em água corrente e sanificados antes e após a retirada da casca em solução de hipoclorito de sódio 200 mg.L-1 e 100 mg.L-1, por 15 e 5 minutos, respectivamente. Os pequis foram acondicionados em embalagem rígida de polipropileno (PP, da seguinte forma: coberta com tampa do mesmo polímero; envolta com filme de policloreto de vinila (PVC 0,014 mm; selada passiva e ativamente (3,2% O2 + 9,2% CO2 e (7,7% O2 + 3,9% CO2 com filme de polietileno (PE + PP 0,060 mm. Conclui-se que as embalagens rígidas seladas passiva e ativamente com filme de PE + PP 0,060 mm não são recomendadas para acondicionar pequi minimamente processado, em razão do nível de O2 estar próximo a 0%, no terceiro dia de armazenamento, o que compromete a sua qualidade. As embalagens rígidas de polipropileno com tampa do mesmo polímero e as envoltas com filme de PVC são as mais indicadas para pequi minimamente processado, visto que não propiciam condições de anaerobiose e nem alteraram expressivamente suas características físicas, físico-químicas e químicas, resultando em uma vida útil de 12 dias de armazenamento a 5 ± 1ºC e UR 90 ± 5%.The aim of this work was to evaluate the efficiency of the use of passive and active modified atmosphere on the maintenance of quality and prolongation of the shelf life of fresh-cut peki fruit stored at 5ºC, for 12 days, through physiological, physical, physico-chemistry and chemistry evaluations. Peki fruit were washed with stream water and sanitized with sodium hypochlorite 200 and 100 mg.L-1, for 15 and 5 minutes, before and after peeling, respectively. Peki fruit were packed into rigid propylene package

  5. Determination of six parabens residues in fresh-cut vegetables using QuEChERS with multi-walled carbon nanotubes and high performance liquid chromatography-tandem mass spectrometry

    Science.gov (United States)

    In this study, an optimized QuEChERS sample preparation method was developed to analyze residues of six parabens: methyl-, ethyl-, n-propyl-, isopropyl-, n-butyl-, and isobutyl-paraben in five fresh-cut vegetables (potato, broccoli, carrot, celery and cabbage) with high performance liquid chromatogr...

  6. Study on the control of enzymatic browning in fresh-cut sweet potatoes%鲜切甘薯酶促褐变调控的研究

    Institute of Scientific and Technical Information of China (English)

    程双; 胡文忠; 马跃; 刘程惠

    2011-01-01

    Fresh-cut sweet potatoes were treated with different concentrations of D-sodium erythorbate and citric acid,study on the reaction of enzymatic browning at 10℃, it revealed the regulation mechanism of different browning inhibitor on fresh-cut sweet potatoes.The results indicated that 0.5%-1.5% of D-sodium erythorbate and 0.01%~0.03% citric acid delayed the occurrence of enzymatic browning, the activities of PPO and POD were inhibited effectively,the content of total phenolic was reduced.But the enzymatic browning was accelerated with the treatment of high-concentration citric acid( ≥0.05% ).Compared with the two browning inhibitor,the inhibition of D-sodium erythorbate was more effectively,the optimum concentration was 1.0%.%采用不同浓度的D-异抗坏血酸钠和柠檬酸分别处理鲜切甘薯,研究其在10℃贮藏过程中的酶促褐变反应,揭示不同褐变抑制剂对鲜切甘薯酶促褐变的调控机制.结果表明,0.5%~1.5%D-异抗坏血酸钠和低浓度(0.01%~0.03%)柠檬酸均延缓了鲜切甘薯酶促褐变的发生,有效抑制了PPO和POD的活性,降低了总酚含量;但高浓度(≥0.05%)柠檬酸处理反而加速了酶促褐变反应的进行.比较两种褐变抑制剂,D-异抗坏血酸钠抑制效果更好,其最佳浓度为1.0%.

  7. 包装材料对鲜切菠萝保鲜效果的影响%Fresh-keeping effects of packaging materials on fresh-cut pineapple

    Institute of Scientific and Technical Information of China (English)

    覃海元; 潘嫣丽; 黄雪明; 黎朝惠

    2011-01-01

    The fresh-keeping effect of different kinds of packaging materials on fresh-cut pineapple was studied. Pineapple were chosen,peeled and cut to wedges(1. 5~2. 0cm chick). Dipped in 0. 5% citric acid solution for 3min,the pineapple wedges were packaged in plastic trays and covered with polyethylene(PE)film,high-density polyethylene(HDPE)bags and polyethylene-polypropylene(PE/PP)composite bags respectively,or packaged in polyester(PET)cup and covered with a PET top having a 3mm diameter hole,and then stored at 5℃ for 10 days. The fresh-cut pineapples were measured at 0,2,4,6,8,10 day respectively. The results showed that PE/PP and PET packaging materials with low gas-permeability could reduce weight loss,browning,juice leakage,electrolyte leakage and dehydroascorbic acid loss more than PE and HDPE films did,but all the packaging materials did almost the same effects on the acid and TSS contents.%研究不同包装材料对鲜切菠萝的保鲜效果。菠萝经挑选、去皮后切成1.5~2.0cm厚的切片,用0.5%柠檬酸溶液浸泡护色3min后,放入塑料托盘中,分别用PE保鲜膜、HDPE保鲜袋和PE/PP复合袋包裹,或放入PET保鲜盒中并用带有1个直径3mm的盖封口,放入5℃的冰柜里冷藏10d;当天和每2d检测1次样品。结果表明,透气性差的PE/PP袋和PET盒较PE膜和HDPE袋更有利于减少鲜切菠萝的失重、褐变、渗汁、相对电导率增加和还原型抗坏血酸损失,但不同包装材料对总酸和可溶性固形物含量的影响不大。

  8. Mulches reduce aphid-borne viruses and whiteflies in cantaloupe

    OpenAIRE

    Summers, Charles G.; Mitchell, Jeffrey P.; Stapleton, James J.

    2005-01-01

    We compared reflective plastic and wheat straw mulches with conventional bare soil for managing aphid-borne virus diseases and silverleaf whitefly in cantaloupe. The occurrence of aphid-borne virus diseases was significantly reduced with both mulches as opposed to bare soil, and reflective plastic performed better than wheat straw. Silverleaf whitefly numbers, both adults and nymphs, were reduced equally by plastic mulch and wheat straw, and were significantly lower than with bare soil. Refle...

  9. Antisense repression of sucrose phosphate synthase in transgenic muskmelon alters plant growth and fruit development

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Hongmei; Ma, Leyuan; Zhao, Cong; Hao, Hui; Gong, Biao [College of Horticulture Science and Engineering, State Key Laboratory of Crop Biology, Shandong Agricultural University, Tai' an, Shandong 271018 (China); Yu, Xiyan, E-mail: yuxiyan@sdau.edu.cn [College of Horticulture Science and Engineering, State Key Laboratory of Crop Biology, Shandong Agricultural University, Tai' an, Shandong 271018 (China); Wang, Xiufeng, E-mail: xfwang@sdau.edu.cn [College of Horticulture Science and Engineering, State Key Laboratory of Crop Biology, Shandong Agricultural University, Tai' an, Shandong 271018 (China)

    2010-03-12

    To unravel the roles of sucrose phosphate synthase (SPS) in muskmelon (Cucumis melo L.), we reduced its activity in transgenic muskmelon plants by an antisense approach. For this purpose, an 830 bp cDNA fragment of muskmelon sucrose phosphate synthase was expressed in antisense orientation behind the 35S promoter of the cauliflower mosaic virus. The phenotype of the antisense plants clearly differed from that of control plants. The transgenic plant leaves were markedly smaller, and the plant height and stem diameter were obviously shorter and thinner. Transmission electron microscope observation revealed that the membrane degradation of chloroplast happened in transgenic leaves and the numbers of grana and grana lamella in the chloroplast were significantly less, suggesting that the slow growth and weaker phenotype of transgenic plants may be due to the damage of the chloroplast ultrastructure, which in turn results in the decrease of the net photosynthetic rate. The sucrose concentration and levels of sucrose phosphate synthase decreased in transgenic mature fruit, and the fruit size was smaller than the control fruit. Together, our results suggest that sucrose phosphate synthase may play an important role in regulating the muskmelon plant growth and fruit development.

  10. Tolerance to a whitefly-transmitted virus causing muskmelon yellows disease in Spain.

    Science.gov (United States)

    Esteva, J; Nuez, F

    1992-08-01

    Muskmelon yellowing disease was one of the most serious problems affecting muskmelon crops along the south-east coast of Spain throughout the 1980s. The causal agent of this disease is a virus that we call muskmelon yellows virus (MYV); MYV is transmitted by the greenhouse whitefly Trialeurodes vaporariorum Westwood. It has proven impossible to find sources of resistance to MYV within a wide collection of Spanish muskmelon landraces and exotic varieties. However, 'Nagata Kin Makuwa' and PI 161375, lines of Asiatic origin, show tolerance to this disease. These two lines were studied together with two others ('Galia' and 'Piel de Sapo' type) that are very susceptible to MYV. The crosses between them (susceptible x tolerant) and the segregant generations derived from these crosses were also investigated. The studies were carried out in two different places and years. The expression of tolerance is influenced by the environment. A parabolic type relationship exists between the average value of percentage of tolerant plants and their variation. This allowed us to quantify the expected response in the segregant generations. The results observed in these generations agreed with a simple genetic control of tolerance. This tolerance, combined with protective measures which delay the infection, can contribute notably to mitigating the effects of MYV.

  11. 低温贮藏对鲜切富士苹果褐变的影响%Effects of Storage Temperature on Browning of Fresh-cut 'Fuji' Apples

    Institute of Scientific and Technical Information of China (English)

    魏敏; 周会玲; 陈小利; 辛付存

    2011-01-01

    The effects on browning and the enzymatic activity of fresh-cut 'Fuji' apples during the storage at 2℃, 6℃and 10℃, respectively were investigated. The results showed that low temperature could delay the browning and senescence of fresh-cut apple by inhibiting the activities of PPO and POD. At the same time, it kept high quality of fresh-cut apple by restraining the increase of MDA and total phenolic contents, reducing the activity of PAL. Under 6'C, the occurrence of browning could be effectively suppressed and the damage of fresh-cut 'Fuji' apple could also be lowered, which maintained the quality of fresh-cut fruit appearance.%研究了鲜切富士苹果在2、6℃和10℃贮藏下的褐变情况及相关酶活性.结果表明:低温冷藏可抑制多酚氧化酶(PPO)、过氧化氢酶(POD)活性,延缓鲜切富士苹果的褐变和衰老;同时冷藏抑制了丙二醛(MDA)含量和总酚含量的上升,降低苯丙氨酸解氨酶(PAL)的活性,保持鲜切富士苹果较高品质.与其他2个温度处理相比,在6℃条件下贮藏鲜切富士苹果,不仅可以有效地抑制褐变的发生,还可以降低温度过低导致对鲜切果体的伤害,从而较好地保持鲜切富士的外观品质.

  12. Métodos de conservação aplicados a melão minimamente processado Conservation methods applied to fresh-cut melon

    Directory of Open Access Journals (Sweden)

    Anaí Peter Batista

    2013-05-01

    Full Text Available O objetivo desta revisão é apresentar alguns métodos de conservação que podem ser utilizados para prolongar a vida útil do melão minimamente processado. Dentre os métodos, serão abordados revestimento comestível, irradiação, antimicrobianos naturais, antioxidantes, agentes de firmeza, atmosfera modificada, branqueamento, luz ultravioleta e alta pressão. Dependendo do método pode haver redução das alterações associadas ao processo mínimo do melão, como a perda de água, alteração da cor e firmeza, alteração do metabolismo e crescimento de micro-organismos, sendo o resultado muitas vezes dependente da cultivar do melão utilizado.The objective of this review is to present some conservation methods that can be used to prolong the life of fresh-cut melon. Among the methods, edible coating, irradiation, natural antimicrobials, antioxidants, firmness agent, modified atmosphere, whitening, ultraviolet light and high pressure will be discussed. Depending on the method, the changes associated to minimum process of melon, such as water loss, change in color and firmness, change in the metabolism and growth of micro-organisms can be reduced and the result is often dependent on the melon cultivar used.

  13. 鲜切雪莲果防褐绿变工艺研究%The Anti-green and Browning Technology for Fresh-cut Yacon

    Institute of Scientific and Technical Information of China (English)

    蔡文韬; 夏延斌; 张音

    2011-01-01

    以雪莲果为试材,研究鲜切雪莲果防褐绿变的工艺.实验中比较了不同护色处理方法的护色效果,采用正交实验筛选出鲜切雪莲果的最佳组合护色条件,雪莲果最优组合防褐绿变的工艺为0.1%CaCl2,0.15%柠檬酸,浸泡30min,在.21℃下冻藏7d,未见褐变和绿变.%Yacon was as experimental material to study the anti-enzymatic browning and greening process. By comparing the different treatment effect of the color-protecting methods, the best color-protecting combination technology of fresh-cut Yacon was determined by orthogonal experiments as: 0.1% calcium chloride, 0.15% citric acid, and soaked time 30 min. The color is little changed at -21℃ in 7 days.

  14. Investigation of Volatiles Emitted from Freshly Cut Onions (Allium cepa L. by Real Time Proton-Transfer Reaction-Mass Spectrometry (PTR-MS

    Directory of Open Access Journals (Sweden)

    Mette Marie Løkke

    2012-11-01

    Full Text Available Volatile organic compounds (VOCs in cut onions (Allium cepa L. were continuously measured by PTR-MS during the first 120 min after cutting. The headspace composition changed rapidly due to the very reactive volatile sulfurous compounds emitted from onion tissue after cell disruption. Mass spectral signals corresponding to propanethial S-oxide (the lachrymatory factor and breakdown products of this compound dominated 0–10 min after cutting. Subsequently, propanethiol and dipropyl disulfide predominantly appeared, together with traces of thiosulfinates. The concentrations of these compounds reached a maximum at 60 min after cutting. Propanethiol was present in highest concentrations and had an odor activity value 20 times higher than dipropyl disulfide. Thus, propanethiol is suggested to be the main source of the characteristic onion odor. Monitoring the rapid changes of VOCs in the headspace of cut onion necessitates a high time resolution, and PTR-MS is demonstrated to be a very suitable method for monitoring the headspace of freshly cut onions directly after cutting without extraction or pre-concentration.

  15. Cellulose-silver nanoparticle hybrid materials to control spoilage-related microflora in absorbent pads located in trays of fresh-cut melon.

    Science.gov (United States)

    Fernández, Avelina; Picouet, Pierre; Lloret, Elsa

    2010-08-15

    The antimicrobial activity of newly developed cellulose-silver nanoparticle hybrid materials was investigated during storage of minimally processed "Piel de Sapo" melon. Silver nanoparticles were produced after in-situ reduction by physical methods of 1% silver nitrate adsorbed on cellulose fibres; they accounted between 5 and 35 nm diameter, and were not aggregated. Fresh-cut melon pieces were stored for 10 days at 4 degrees C under natural modified atmosphere packaging, in presence or absence of silver loaded absorbent pads. The evolution of headspace gas composition, quality parameters, and the antimicrobial activity against spoilage-related microorganisms were investigated. The cellulose-silver nanoparticle hybrid materials released silver ions after melon juice impregnated the pad. The released silver ions were particularly useful to control the population of spoilage-related microorganisms in cellulose based absorbent pads in contact with vegetable matrices, showing a low chelating effect against silver ions; the lag phases of the microorganisms were considerably incremented and microbial loads in the pads remained in average approx. 3 log(10) CFU/g below the control during the investigated storage period. Furthermore, the presence of silver loaded absorbent pads retarded the senescence of the melon cuts, presenting remarkably lower yeast counts, lower degrees Brix values, and a juicier appearance after 10 days of storage.

  16. Evaluation of HACCP system implementation on the quality of mixed fresh-cut salad prepared in a university canteen: a case study.

    Science.gov (United States)

    Osimani, Andrea; Aquilanti, Lucia; Clementi, Francesca

    2015-01-01

    The increasing awareness that foods can represent vehicles for health risk factors has caused scientists and public authorities to multiply their efforts to reduce these risks to within acceptable limits. Nevertheless, some challenging issues still remain unsolved and new ones have recently emerged, such as the increase in outbreaks of foodborne diseases originating from the consumption of meals at catering facilities. The study described in this article was aimed at evaluating the microbiological quality of mixed fresh-cut salads at an Italian university canteen operating in conformity with the hazard analysis and critical control point (HACCP) system. The effectiveness of the preventive and corrective measures taken was also assessed with respect to the frequency of unsatisfactory salad samples. During the investigation, E. coli, Salmonella spp., and Listeria monocytogenes were never detected. By contrast, a high number of samples exceeded the mandatory or suggested limits for food processing hygiene (in terms of mesophilic aerobes, coliforms, Staphylococcus aureus, Bacillus cereus, and sulfite-reducing clostridia counts). Despite the introduction of a series of preventive and corrective actions, the results were only partially satisfactory; this was most likely due to the impossibility of having available an adequate level of human resources that are indispensable to correctly putting the HACCP procedures into daily practice.

  17. Changes in bioactive compounds and oxidative enzymes of fresh-cut pomegranate arils during storage as affected by deficit irrigation and postharvest vapor heat treatments.

    Science.gov (United States)

    Peña-Estévez, María E; Gómez, Perla A; Artés, Francisco; Aguayo, Encarna; Martínez-Hernández, Ginés Benito; Galindo, Alejandro; Torecillas, Arturo; Artés-Hernández, Francisco

    2016-12-01

    The effect of postharvest vapor heat treatments at 95℃ (4, 7, and 10 s) regarding a conventional sanitizing treatment with 100 mg NaClO l(-1) on enzyme activities (phenylalanine ammonia lyase, polyphenol oxidase, and peroxidase), phenolic content, and total antioxidant capacity of fresh-cut pomegranates arils throughout 18 days at 5℃ was studied. Furthermore, the effect of two sustained deficit irrigation (SDI) strategies, compared to a standardly irrigated control (CTRL), was also studied on such quality parameters throughout storage. Arils from CTRL-irrigated fruit registered phenylalanine ammonia lyase, peroxidase, and polyphenol oxidase initial activities of 60.6, 382, and 14.4 U g(-1) fw, respectively. Arils from sustained deficit irrigation fruit registered 46-58% lower phenylalanine ammonia lyase values while polyphenol oxidase and peroxidase activities did not register great variants (fruit although no great peroxidase and polyphenol oxidase (fruit registered higher phenolic content than those values reported for CTRL samples. However, phenolic compounds decreased during storage, in a greater extent for sustained deficit irrigation samples, although 7 s arils achieved better phenolic compounds retention in sustained deficit irrigation samples. Vapor heat treatments reduced up to twofold the total antioxidant capacity losses observed in samples sanitized by conventional NaOCl treatment during shelf life. Conclusively, postharvest vapor heat treatment for 7 and 10 s used to extend the shelf life of pomegranate arils up to 18 days at 5℃ reduced the losses of health-promoting compounds during storage compared to conventional NaOCl sanitizing treatment. © The Author(s) 2016.

  18. Utilization of physicochemical variables developed from changes in sensory attributes and consumer acceptability to predict the shelf life of fresh-cut mango fruit.

    Science.gov (United States)

    Salinas-Hernández, Rosa María; González-Aguilar, Gustavo A; Tiznado-Hernández, Martín Ernesto

    2015-01-01

    Sensory evaluation is the ideal tool for shelf-life determination. With the objective to develop an easy shelf-life indicator, color (L*, a*, b*, chroma and hue angle), total soluble solids (TSS), firmness (F), pH, acidity, and the sensory attributes of appearance, brightness, browning, odor, flavor, texture, color, acidity and sweetness were evaluated in fresh cut mangoes (FCM) stored at 5, 10, 15 and 20 °C. Overall acceptability was evaluated by consumers. Correlation analysis between sensory attributes and physicochemical variables was carried out. Physicochemical cut-off points based on sensory attributes and consumer acceptability was obtained by regression analysis and utilized to estimate FCM shelf-life by kinetic models fitted to each variable. The validation of the model was done by comparing the shelf life estimated by kinetic models and consumers. It was recorded large correlations between appearance, brightness, and color with L*; appearance and color with chroma and hue angle; sweetness and flavor with TSS, and between F and texture. The shelf life estimated based on consumer using a 9 point hedonic scale was in the range of 10-12, 2.3-2.6, 1.3-1.5 and 1.0-1.1 days for 5, 10, 15 and 20 °C. It was recorded large correlation coefficients between the shelf life estimated by consumer acceptability scores and physicochemical variables. Kinetic models based on physicochemical variables showed a tendency to overestimate the shelf life as compared with the models bases on the sensory attributes. It was concluded that physicochemical variables can be used as a tool to estimate the FCM shelf life.

  19. Combined effects of thermosonication and slightly acidic electrolyzed water on the microbial quality and shelf life extension of fresh-cut kale during refrigeration storage.

    Science.gov (United States)

    Mansur, Ahmad Rois; Oh, Deog-Hwan

    2015-10-01

    This study evaluated the efficacy of thermosonication combined with slightly acidic electrolyzed water (SAcEW) on the shelf life extension of fresh-cut kale during storage at 4 and 7 °C. Each kale (10 ± 0.2 g) was inoculated to contain approximately 6 log CFU/g of Listeria monocytogenes. Each inoculated or uninoculated samples was dip treated at 40 °C for 3 min with deionized water, thermosonication (400 W/L), SAcEW (5 mg/L), sodium chlorite (SC; 100 mg/L), sodium hypochlorite (SH; 100 mg/L), and thermosonication combined with SAcEW, SC, and SH (TS + SAcEW, TS + SC, and TS + SH, respectively). Growths of L. monocytogenes and spoilage microorganisms and changes in sensory (overall visual quality, browning, and off-odour) were evaluated. The results show that lag time and specific growth rate of each microorganism were not significantly (P > 0.05) affected by treatment and storage temperature. Exceeding the unacceptable counts of spoilage microorganisms did not always result in adverse effects on sensory attributes. This study suggests that TS + SAcEW was the most effective method to prolong the shelf life of kale with an extension of around 4 and 6 days at 4 and 7 °C, respectively, and seems to be a promising method for the shelf life extension of fresh produce.

  20. Inibição do escurecimento enzimático de banana maçã minimamente processada Enzimatic browning inhibition of fresh-cut apple banana

    Directory of Open Access Journals (Sweden)

    Ânderson Adriano Martins Melo

    2006-03-01

    Full Text Available Objetivou-se, neste trabalho, avaliar o efeito do ácido ascórbico (AA, do cloreto de cálcio (CC, do cloridrato de L-cisteína (Cis e EDTA, na prevenção do escurecimento enzimático de banana maçã minimamente processada. Foram utilizadas as combinações: (i AA 1%+CC 1%+Cis 0,5%, (ii AA 1%+CC 1%+Cis 1%, (iii AA 1%+CC 1%+Cis 1,5% e (iv EDTA 1%, constituindo quatro tratamentos de um delineamento inteiramente casualizado. Produtos minimamente processados não tratados quimicamente não foram analisados, considerando-se seu acentuado escurecimento e sua vida de prateleira inferior a 6 h. As bananas foram tratadas com hipoclorito de sódio, fatiadas, imersas nos tratamentos químicos, acondicionadas em embalagens rígidas envoltas com filme PVC 30 µm e armazenadas durante cinco dias a 5+1°C e 85+3% UR. Amostras foram analisadas diariamente, durante os cinco dias de armazenamento. Os tratamentos contendo AA 1%+CC 1%+Cis 1% e AA 1%+CC 1%+Cis 1,5% determinaram os maiores valores de acidez titulável e menores de pH. Observaram-se aumentos no valor a* e redução nos valores b* e L* na banana maçã minimamente processada, independente do tratamento químico, durante o armazenamento. O tratamento AA 1%+CC 1%+Cis 1,5% foi o mais efetivo na prevenção das modificações dos valores a*, b* e L*, associados à coloração das rodelas. Observou-se aumento na atividade da polifenoloxidase (PPO e peroxidase (POD durante o armazenamento das rodelas de banana, independente do tratamento, à exceção da redução observada na atividade da PPO, nos produtos tratados com EDTA. Os tratamentos contendo EDTA e AA 1%+CC 1%+Cis 1,5% foram os mais efetivos na contenção do aumento das atividades da PPO e POD, respectivamente.The goal of this work was to evaluate the effect of ascorbic acid (AA, calcium chloride (CC, L-cysteine hydrochloride (Cys and EDTA on prevention of enzymatic browning of fresh-cut apple banana. The following combinations were used: (i AA 1

  1. Qualidade de mandioquinha-salsa minimamente processada e armazenada sob atmosfera modificada Quality of fresh-cut peruvian carrot: use of modified atmosphere

    Directory of Open Access Journals (Sweden)

    Elisângela Elena Nunes

    2009-10-01

    para prolongar a vida útil de mandioquinhas-salsa minimamente processadas, preservando seus atributos de qualidade. Diante da avaliação sensorial realizada, a aparência e a cor das fatias de mandioquinha-salsa mantiveram-se aceitáveis para o consumo até o final do período de armazenamento.The aim of this research was to verify the effect of the passive and active modified atmosphere on the conservation of fresh-cut peruvian carrot, cv. Amarela de Senador Amaral, purchased from a commercial crop of Lavras, MG, Brazil. The roots were screened, washed with neutral detergent and rinsed in running water. Afterwards, they were immersed into a solution of 300mg L-1 sodium hypochlorite for 15 minutes and dried at room temperature. The roots were peeled and cut in slices of about 1cm of thickness and immersed into a solution of 50mg L-1 sodium hypochlorite for 10 minutes, drained in plastic sieves and packed. The trays containing the slices of Peruvian carrot were stored in a cold room (5±1°C and 98% RH for 15 days. The following analyses were performed every 3 days: : pH, titrable acidity, total soluble solids, firmness, L* and b* values, starch and sensorial evaluation (appearance and color. The experimental design was completely randomized (CRD in a 3 x 6 factorial scheme, with 3 sorts of atmospheres (passive; active with initial injection of the mixtures: 2% O2 + 10% CO2 e 5% O2 + 5% CO2 and 6 times of storage (0, 3, 6, 9, 12 and 15 days with 3 replicates. The average values of pH, titrable acidity, soluble solids and firmness found in this work were 6.79, 0.13% of malic acid, 4.04°Brix and 5.17 N, respectively. The active modified atmosphere (5% de O2 + 5% CO2 determined higher L* value to the fresh cut Peruvian carrots at the sixth and twelfth day of storage as compared with the active (2% of O2 + 10% CO2. The active modified atmosphere with 5% O2 + 5% CO2 determined higher b* values and starch contents to the slices of Peruvian carrots as compared with the

  2. The Research Progress on Inhibition of Fresh-cut Fruits and Vegetable Enzymatic Bromning%鲜切果蔬酶促褐变控制研究进展

    Institute of Scientific and Technical Information of China (English)

    胡晓露; 缪丽华

    2012-01-01

    褐变是影响鲜切果蔬外观品质的一个重要因素。本文介绍了抑制鲜切果蔬酶促褐变的物理、化学等方法。旨在为以后的研究提供一定的依据。%Enzymatic browning is one of important factors impacting quality of fresh-cut fruits and vegetables. Physical inhibition ways and chemical inhibition methods of fresh-cut fruits and vegetable enzym atic browning is reviewed in this text. This study is designed to providing reference to the de'velopment of longan drying.

  3. 没食子酸丙酯、壳聚糖对鲜切生姜保鲜特性的影响%Effects of Propyl Gallate and Chitosan on Preservation of Fresh-cut Ginger During Storage

    Institute of Scientific and Technical Information of China (English)

    丁君; 吴昊; 王成荣

    2016-01-01

    In this experiment,the effects of propyl gallate (PG)and chitosan on preservation of fresh-cut ginger during storage are investigated. Select gingers without scab and mechanical deterioration as test materials.The gingers are cut into 5 mm-thickness sheets after rinsing and peeling.The fresh-cut gingers are socked with three different treatments,including 0.20% PG, 1.50% chitosan and 0.20% PG+1.50% chitosan,and fresh-cut gingers without any reagent are used as control.The fresh-cut gingers are stored at 14 ℃ (± 1.0 ℃),then the changes of weight loss, browning degree,POD activity,MDA content,Vc content,hardness,elasticity and chewiness of fresh-cut gingers are determined.The results show that the three different treatments could delay the rise of weight loss and MDA content with a certain degree,reduce the browning speed,and inhibit the POD activity.At the same time,three different treatments could maintain the hardness and Vc content of fresh-cut gingers at a higher level and the chewiness and elasticity of fresh-cut gingers at a lower level.Compare with 0.20% PG and 1.50% chitosan,the effect of 0.20% PG + 1.50%chitosan treatment on preservation of fresh-cut ginger is the best.%试验研究了没食子酸丙酯(PG)、壳聚糖对鲜切生姜保鲜效果的影响。挑选无病虫害、无机械损伤的生姜,清洗去皮,用不锈钢刀切分成5 mm 薄片,用0.20% PG,1.50%壳聚糖和0.20% PG+1.50%壳聚糖3个不同溶液浸泡处理,以未加处理的鲜切生姜为对照组,在14℃(±1.0℃)恒温库中贮藏,每隔3天测定其失重率、褐变度、过氧化物酶(POD)活力、丙二醛含量、Vc 含量、硬度、弹性以及咀嚼性的变化。结果表明:3种不同处理均能够在一定程度上延缓鲜切生姜失重率和丙二醛含量的升高,降低鲜切生姜的褐变速率,抑制 POD 活性;同时,3种不同处理均使得鲜切生姜的 Vc 含量和硬度维持在较高水平,而其咀嚼性和弹性保持在较低水平。3

  4. 涂膜处理对鲜切山药褐变及抗氧化性的影响%Effect of Coating on Browning and Antioxidant Activity of Fresh-Cut Yam

    Institute of Scientific and Technical Information of China (English)

    马利华; 秦卫东; 陈学红; 王磊

    2012-01-01

    为保持鲜切山药的色泽及抗氧化性,延长其货架期,研究壳聚糖、卡拉胶、海藻酸钠及复合涂膜剂对鲜切山药涂膜处理后,在5℃贮藏期间褐变及抗氧化性的影响。结果表明:壳聚糖1.57%+卡拉胶0.9%+海藻酸钠1.55%涂膜后,鲜切山药储存期间,可明显降低山药的褐变程度及抑制PPO的比活力,防止贮藏后期酚类物质的氧化,提高鲜切山药的整体抗氧化能力。%In order to preserve the color and antioxidant activity of fresh-cut yam and extend its shelf life, the effects of different types of coating treatment (chitosan alone, carrageenan alone, sodium alginate alone, and all of them) on browning degree and antioxidant activity of fresh-cut yam during storage at 5 ℃ were investigated. The results showed that a mixture of 1.57% chitosan, 0.9% carrageenan and 1.55% sodium alginate could inhibit PPO activity and reduce the browning degree of fresh-cut yam during storage, and prevent polyphenol oxidation and increase the total antioxidant activity of fresh-cut yam during the late period of storage.

  5. 不同质量浓度臭氧化水对鲜切西兰花贮藏品质的影响%Effect of Ozonated Water with Various Concentrations on Storage Quality of Fresh-cut Broccoli

    Institute of Scientific and Technical Information of China (English)

    王宏延; 曾凯芳; 贾凝; 陈存坤; 王文生

    2012-01-01

    采用不同质量浓度臭氧化水处理鲜切西兰花。结果表明:质量浓度2.0mg/L的臭氧化水处理组保鲜效果最优,在贮藏12d时与对照组相比,质量损失率降低24.37%,VC含量提高40.7%,多酚氧化酶酶活降低23.5%,过氧化物酶酶活降低25.6%;在4℃的条件下,质量浓度2.0mg/L的臭氧化水处理组鲜切西兰花贮藏期可达到15d。%Ozonated water can be used for disinfection,sterilization,deodorization and preservation with multiple advantages such as rapid sterilization rate,simple operation and without residues.It can be used directly for the sterilization of fresh-cut vegetables so that it is a potential technology of cold sterilization and green sterilization.The results showed that the best preservation effect on fresh-cut broccoli was observed at the condition of 2 mg/L ozonated water.Compared with the control,ozonated water-treated fresh-cut broccoli after storage for 12 days revealed a reduction by 24.37% for weight loss rate,an improvement by 40.7% for vitamin C,a decline by 23.5% for polyphenol oxidase activity and a decrease by 25.6% for peroxidase activity.The storage life of fresh-cut broccoli subjected to treatment with 2 mg/L ozonated water can be extended to 15 days at the storage temperature of 4 ℃.

  6. Effects of Different Storage Temperatures on Quality of Fresh-cut Yam%不同贮藏温度对鲜切山药品质的影响

    Institute of Scientific and Technical Information of China (English)

    赵梅

    2012-01-01

    In order to study the effects of different storage temperature on quality of fresh-cut yam, Chinese yam was used as raw material. The fresh-cut yam was put at 0℃, 4℃, 6℃, l0℃ and room temperature. The factors that were weight loss rate, cell membrane permeability, browning index, and PPO activity were measured. The results showed that: low temperature (0-4℃) could inhibit water evaporation and reduce weight loss rate, delay cell membrane permeability increase and reduce the rate of cell membrane permeability, inhibit enzymatic browning and reduce browning degree, maintain low PPO activity. The quality of fresh-cut yam was maintained. 0 to 4℃ was safe and suitable for preserving fresh-cut yam.%以山药为原料,研究了不同贮藏温度对鲜切山药品质的影响.将鲜切山药分别置于0、4、6、10℃和室温,测定鲜切山药失重率、细胞膜渗透率、褐变度和多酚氧化酶活性(PPO)各项指标的变化.结果表明:与室温相比,0~4℃的低温贮藏能抑制水分蒸发从而有效降低鲜切山药失重率,延缓鲜切山药细胞膜透性上升,降低细胞膜渗透率,显著抑制了酶促褐变,大大降低了褐变度,维持较低的多酚氧化酶活性,较好地保持鲜切山药的品质.0~4℃是鲜切山药适宜的贮藏温度.

  7. Chlorine Dioxide Gas Treatment of Cantaloupe and Residue Analysis

    OpenAIRE

    Kaur, Simran

    2013-01-01

    Chlorine dioxide is a selective oxidant and powerful antimicrobial agent. Previous work has shown that treatment of cantaloupe with chlorine dioxide gas at 5 mg/L for 10 minutes results in a 4.6 and 4.3 log reduction of E. coli O157:H7 and L. monocytogenes respectively. A significant reduction (p Current analytical methods for chlorine dioxide and chloroxyanions are only applicable to aqueous samples. Some of these methods have been used to determine surface residues in treated products by...

  8. Research on application of two kinds of natural food preservatives on fresh cut vegetables preservations%2种天然食品防腐剂在鲜切蔬菜保鲜中的应用研究

    Institute of Scientific and Technical Information of China (English)

    李晶莹; 王筠婷; 葛婷; 孙雨宏; 丁敬争; 任建军

    2015-01-01

    This paper introduces chitosan and tea polyphenols as raw material to study the effect of these two kinds of natural food preservatives on fresh cut green peppers and cucumbers storage quality. In addition, the different effects with various concentrations of chitosan and tea polyphenol as coating preservation of fresh cut green peppers and cucumbers were compared. The conclusion is as follows: 1% of Chitosan and 2% of tea polyphenol play significant role in food preservation to fresh cut green peppers and cucumber.%壳聚糖和茶多酚作为一种安全、无毒、有效的涂膜保鲜剂,近年来被广泛地研究和应用.分别以壳聚糖和茶多酚为材料,研究它们对鲜切青椒和黄瓜贮藏品质的影响,并比较了不同浓度的壳聚糖及茶多酚涂膜保鲜鲜切青椒和黄瓜的效果.试验结果表明,1%的壳聚糖、2%的茶多酚在一定的环境条件下对鲜切青椒和黄瓜贮藏具有良好的保鲜效果.

  9. Effect of Meloidogyne javanica and M. incognita on Resistance of Muskmelon Cultivars to Fusarium Wilt

    Directory of Open Access Journals (Sweden)

    I. Naji

    2004-12-01

    Full Text Available A growth chamber experiment was conducted to study the interaction between Meloidogyne javanica and/or M. incognita and the Fusarium wilt fungus Fusarium oxysporum f. sp. melonis, using three muskmelon cultivars differing in their resistance to the fungus. Inoculations were carried out l. with the wilt fungus alone, 14 and 28 days after transplanting; and 2. with the wilt fungus plus one or both root-knot nematodes, either directly upon transplanting, or 14 or 28 days after transplanting. In the course of the test all muskmelon cultivars, irrespective of their initial resistance to the wilt, almost completely lost their resistance when infected with M. javanica; resistance was also impaired but to a lesser extent with M. incognita. Wilting of 100% in the resistant and moderately resistant muskmelon cultivars inoculated with M. javanica + F. oxysporum f. sp melonis occurred 14 days earlier than in muskmelon inoculated with the fungus alone. Also, M. javanica was more severe on the plants than M. incognita. In all three cultivars, both root-knot nematode species hastened expression of plant wilting, which took 12.1 days with M. javanica, 14.8 days with M. incognita, and 12.3 days with both species combined, compared with 22.7 days for plants inoculated with Fusarium oxysporum f. sp. melonis alone. Moreover, the onset of wilting required 9–13.3 days when the nematode infection preceded F. oxysporum f. sp. melonis inoculation by two weeks, compared with 16.7– 19.7 days when the nematode and fungus were inoculated simultaneously 14 days after transplanting, indicating plant preconditioning by the nematode.

  10. Effects of Rhodotorula sp on the Physiological Metabolism of Fresh-cut Apples%红酵母菌对鲜切苹果生理代谢的影响

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

      将从富士苹果皮中分离出的红酵母菌配制成不同浓度(105、106、107 CFU/mL)的菌悬液处理鲜切苹果,研究红酵母菌对鲜切苹果在10℃条件下贮藏10 d期间可溶性蛋白含量及相关酶活性的影响。结果表明,红酵母菌能够延迟鲜切苹果可溶性蛋白含量出现最大值的时间,有助于维持细胞的正常代谢。另外,红酵母菌能够抑制过氧化物酶(POD)、多酚氧化酶(PPO)活性和丙二醛(MDA)含量的上升,可有效控制鲜切苹果细胞膜的过氧化作用,延缓苹果的氧化和组织的衰老。但在贮藏前期,红酵母菌也激活了鲜切苹果的多聚半乳糖醛酸酶(PG)活性,加速了苹果的软化。%Fresh-cut apples were treated with different concentrations of Rhodotorula sp (105, 106, 107 CFU/mL) which separated from fresh-cut Fuji apple peel. This article studied the effects of Rhodotorula sp on the soluble protein content and activities of related enzymes of fresh-cut apples during 10 days storage at 10 ℃. The results showed that, Rhodotorula sp could delay the time of the maximum of soluble protein content, and could help to maintain the normal metabolism of cell. In addition, Rhodotorula sp could inhibit the increase of POD and PPO activities and MDA content, effectively control the peroxidation of cell film of fresh-cut apple, and delay oxidation of apple and senescence of tissue. But in the early storage, Rhodotorula sp also activated polygalacturonase (PG) activity, and accelerated the softening of fresh-cut apple.

  11. 不同甜瓜品种鲜切加工特性评价%Suitability of Different Melon Cultivars for Fresh-Cut Processing

    Institute of Scientific and Technical Information of China (English)

    王丽; 张学杰; 李慧; 王怀松

    2012-01-01

    Hardness, soluble solid content (SSC), sensory quality, VC content, and marketable fruit percentage were measured on melon fruits from four different cultivars, reticulate melon (Zhongmi No. 55 and Huami No. 2) and smooth rind melon (Zhongmi No. 116 and Yujinxiang) at days 0, 14 and 28 of post-harvest storage at 10 ℃. Meanwhile, grey correlation analysis was used to evaluate the experimental data. The suitability of the melon cultivars for fresh-cut processing followed the decreasing order of Huami No. 2 〉 Zhongmi No. 55 〉 Zhongmi No. 116 〉 Yujinxiang. Huami No. 2 was characterized by higher marketable fruit percentage at the early harvest stage, better sensory quality and higher VC content, and Zhongmi No. 55 showed the characteristics of higher marketable fruit percentage and better sensory quality and storage tolerance.%以网纹(中蜜55号、华蜜2号)、光皮(中蜜116、玉金香)两个类型甜瓜共4个品种为实验材料,分别测定其产量及采收后贮藏(10℃)0、14、28d时的硬度、可溶性固形物含量、感官品质、VC含量及出品率,实验结果采用灰色关联度分析方法进行综合评价。结果表明:供试甜瓜品种用于鲜切加工的优先排序依次为华蜜2号、中蜜55号、中蜜116和玉金香,其中华蜜2号在采摘初期表现出产量高、感官品质好、VC含量高的特点,中蜜55号呈现出产量高、品质较好、耐贮性好的特征。

  12. Effect of cut type on fresh-cut 'menina brasileira' zucchini quality Efeito do tipo de corte na qualidade de abobrinha 'Menina Brasileira' minimamente processada

    Directory of Open Access Journals (Sweden)

    Brígida Monteiro Vilas Boas

    2011-12-01

    Full Text Available Market sales of ready-to-use fresh fruit and vegetables have grown quickly in the recent years as a result of changes in consumer attitudes. The goal of this work was to evaluate the effect of two kinds of cuts on the physiological, physical, physical-chemical, chemical and biochemical traits of fresh-cut 'Menina Brasileira' zucchini stored in rigid polypropylene packages, with lids of the same material containing sliced and grated zucchini and stored at 5º C, for 15 days. The variables respiratory rate, pH, L* value, soluble pectin, PME and PG activity, was interactively affected by the cut type and storage time factors. The variables mass loss, phenylalanine ammonia-lyase activity and total pectin variable were only significantly affected by storage time factor. It can be concluded that sliced 'Menina Brasileira' zucchini shows a higher titratable acidity and soluble solids and a lower respiratory rate, pectin soluble and phenylalanine ammonia-lyase activity when compared with grated zucchini, contributing to the preservation of quality attributes.As vendas no mercado de frutas e hortaliças frescas prontas para o consumo têm crescido rapidamente nos últimos anos como resultado de mudanças nas atitudes dos consumidores. Neste trabalho objetivou-se avaliar o efeito de dois tipos de cortes nas características fisiológicas, físicas, químicas, físico-químicas e bioquímicas de abobrinha 'Menina Brasileira' minimamente processada, armazenada a 5º C em embalagens de polipropileno rígido, com tampas do mesmo material, contendo abobrinha fatiada e ralada, por 15 dias. As variáveis taxas respiratórias, pH, valor L*, pectina solúvel, atividade de PME e PG, foram interativamente afetadas pelos fatores tipo de corte e tempo de armazenamento. As variáveis perda de massa, atividade da fenilalanina amônia-liase e a pectina total foram afetadas significativamente apenas pelo fator tempo de armazenamento. Pode-se concluir que a abobrinha

  13. Effects of crude protein level in concentrate supplements on animal performance and nitrogen utilization of lactating dairy cows fed fresh-cut perennial grass.

    Science.gov (United States)

    Hynes, D N; Stergiadis, S; Gordon, A; Yan, T

    2016-10-01

    Nitrogen pollution of air and ground water from grazing cattle is of increasing concern. Although several studies have investigated mitigation strategies for nitrogen output from dairy cows fed conserved forages and concentrates, similar research on fresh-cut grass in addition to production parameters is limited. The current study, using 3dietary treatments and incorporating 2 genotypes, was designed to evaluate the effects of concentrate crude protein (CP) levels on animal production and nitrogen utilization efficiency (NUE) in lactating dairy cows. Twelve multiparous cows (6 Holstein and 6 Holstein × Swedish Red) were used in a changeover study with three 25-d periods and 3 diet treatments. Low, medium and high CP concentrate [14.1, 16.1, and 18.1%, respectively, dry matter (DM) basis] diets were fed at 32.8% DM intake combined with good-quality zero-grazed perennial ryegrass (18.2% CP, DM basis). Each period consisted of an adaptation phase (18d) housed as a single group, a 1-d adaptation phase in individual stalls, and a 6-d measurement phase with feed intake and feces, urine, and milk output recorded. We observed no significant interaction between cow genotype and concentrate CP level on any animal performance or NUE parameter. Total DM intake, milk yield and composition, and NUE were not affected by dietary treatment. However, increasing concentrate CP level increased (1) N intake by 42g/d and excretion in urine and manure by 38 and 40g/d, respectively, and (2) the ratio of urine N over manure N. Feeding high CP rather than low CP concentrate increased milk urea N (MUN) content by 3.6mg/dL and total MUN output by 1.08g/d. Crossbred cows had lower grass DM intake, total DM intake, total N intake, and energy-corrected milk yield. However, cow genotype had no significant effect on NUE or MUN parameters. Equations have been developed to predict urine N excretion using MUN output as a sole predictor or in combination with dietary CP level. The present study

  14. Antisense suppression of an acid invertase gene (MAI1) in muskmelon alters plant growth and fruit development.

    Science.gov (United States)

    Yu, Xiyan; Wang, Xiufeng; Zhang, Wenqian; Qian, Tingting; Tang, Guimin; Guo, Yankui; Zheng, Chengchao

    2008-01-01

    To unravel the roles of soluble acid invertase in muskmelon (Cucumis melo L.), its activity in transgenic muskmelon plants was reduced by an antisense approach. For this purpose, a 1038 bp cDNA fragment of muskmelon soluble acid invertase was expressed in antisense orientation behind the 35S promoter of the cauliflower mosaic virus. The phenotype of the antisense plants clearly differed from that of control plants. The transgenic plant leaves were markedly smaller, and the stems were obviously thinner. Transmission electron microscopy revealed that degradation of the chloroplast membrane occurred in transgenic leaves and the number of grana in the chloroplast was significantly reduced, suggesting that the slow growth and weaker phenotype of the transgenic plants may be due to damage to the chloroplast ultrastructure, which in turn resulted in a decrease in net photosynthetic rate. The sucrose concentration increased and levels of acid invertase decreased in transgenic fruit, and the fruit size was 60% smaller than that of the control. In addition, transgenic fruit reached full-slip at 25 d after pollination (DAP), approximately 5 d before the control fruit (full-slip at 30 DAP), and this accelerated maturity correlated with a dramatic elevation of ethylene production at the later stages of fruit development. Together, these results suggest that soluble acid invertase not only plays an important role during muskmelon plant and fruit development but also controls the sucrose content in muskmelon fruit.

  15. Mangas minimamente processadas amadurecidas naturalmente ou com etileno e armazenadas em diferentes embalagens Fresh cut mangos ripped naturaly or induced by ethylene and stored in different packges

    Directory of Open Access Journals (Sweden)

    Bianca Sarzi de Souza

    2006-08-01

    Full Text Available Avaliaram-se produtos minimamente processados de mangas 'Tommy Atkins' amadurecidas naturalmente ou com etileno. Os frutos amadurecidos com aplicação de etileno foram colhidos no estádio "meio-maturo" (de vez e tratados com etileno (1g.L-1 e mantidos em câmaras, por 12 horas, a 23-25ºC e 85-90% UR. Os frutos foram selecionados, lavados com detergente, sanitizados (200mg.L-1 de cloro e armazenados por 12 horas, a 10ºC. Após este período, foram processados sob condições assépticas, a 12ºC, acondicionados em embalagem PET ou bandeja de poliestireno expandido recoberta por filme de PVC e armazenados a 3ºC. Foram avaliados, a cada 3 dias, a resistência e a coloração da polpa, os teores de ácido ascórbico, sólidos solúveis (SS, acidez titulável (AT, carboidratos solúveis, redutores e amido, relação SS/AT, pH e atividade da peroxidase. Durante o período de armazenamento, os pedaços de manga tornaram-se mais firmes e mantiveram-se amarelos, porém mais escurecidos, o que foi indicado por redução na luminosidade. Os teores de ácido ascórbico nos pedaços das mangas amadurecidas com etileno apresentaram-se menores que os das amadurecidas naturalmente. A acidez apresentou tendência de redução durante o armazenamento, com as amadurecidas com etileno apresentando os maiores valores e os menores pH. Os produtos de mangas amadurecidas com etileno apresentaram os maiores valores de SS, mas menor relação SS/AT, indicando gosto mais azedo. Os teores de carboidratos solúveis e de amido não apresentaram variação com tendência definida, mas os de carboidratos redutores apresentaram tendência de acréscimo, e a atividade da peroxidase, de decréscimo durante o armazenamento. Os produtos de mangas amadurecidas naturalmente foram superiores aos amadurecidos com etileno, mantendo boa qualidade e aparência adequada para a comercialização até o 13º dia, enquanto os das amadurecidas com etileno, por 11 dias.Fresh cut 'Tommy

  16. Vida útil de produto minimamente processado composto por abóbora, cenoura, chuchu e mandioquinha-salsa Shelf life of fresh-cut composed of vegetables

    Directory of Open Access Journals (Sweden)

    Juliana Alvarenga Alves

    2010-02-01

    Full Text Available Objetivou-se avaliar o efeito do tempo de armazenamento sobre a qualidade de produto minimamente processado à base de hortaliças: abóbora (Cucurbita moschata Duch, cenoura (Daucus carota L., chuchu (Sechium edule Swartz e mandioquinha-salsa (Arracacia xanthorrhiza Bancroft. As hortaliças foram sanificadas em hipoclorito de sódio 200 mg.L-1, por 5 minutos, descascadas, manualmente, e cortadas utilizando-se processador. O produto processado foi sanificado em hipoclorito de sódio 50 mg.L-1, por 3 minutos, e apenas as mandioquinhas-salsa foram imersas em solução de ácido ascórbico 1%, por 2 minutos. As embalagens flexíveis de polietileno de baixa densidade linear (25 x 20 cm, contendo 400 g do "mix", foram armazenadas a 5ºC e 99% UR, por 8 dias. A firmeza e o valor L* das hortaliças estudadas não alteraram com o tempo de armazenamento. Os valores a* e b* da abóbora não oscilaram durante o armazenamento. O valor a* da mandioquinha-salsa e do chuchu aumentou e o da cenoura diminuiu com o armazenamento, enquanto o valor b* da cenoura, do chuchu e da mandioquinha-salsa reduziu. O "mix" apresentou taxa de perda de massa muito baixa e ascensão respiratória até o oitavo dia. A atmosfera de equilíbrio, em torno de 2,93% de O2 e 7,06% de CO2, foi alcançada no interior da embalagem, contendo o "mix", a partir do segundo dia. Não foi detectada a presença de coliformes a 45ºC e Salmonella sp. em nenhuma amostra. Os coliformes a 35ºC aumentaram durante o armazenamento. Conclui-se que, o produto minimamente processado, à base de hortaliças mantém a sua qualidade por 8 dias a 5ºC.The objective of this work was to evaluate the effect of storage time on the quality of fresh-cut product made up of four vegetables: pumpkin (Cucurbita moschata Duch, carrot (Daucus carota L., chayote (Sechium edule Swartz, and peruvian carrot (Arracaia xanthorrhiza Bancroft. The vegetables were sanitized in sodium hypochlorite solution (200 mg.L-1 for 5

  17. The Effect of Short-term Storage and the Hot Water Treatment of Fresh-Cut Pepper Fruit cv. ‛Blondy F1’ and ‛Yecla F1’ on the Content of Bioactive Compounds and Antioxidant Properties

    National Research Council Canada - National Science Library

    Justyna I. Szwejda-Grzybowska; Ryszard Kosson; Maria Grzegorzewska

    2016-01-01

    The aim of the experiment was to determine the changes in the contents of bioactive compounds and antioxidant/antiradical activity in fresh-cut fruits of sweet pepper cv. ‘Blondy F ’ and ‘Yecla F...

  18. Using reflectance and photography to detect ozone damage to cantaloupe plants

    Science.gov (United States)

    Gausman, H. W.; Escobar, D. E.; Rodriguez, R. R.; Thomas, C. E.; Bowen, R. L.

    1978-01-01

    Laboratory and field reflectance measurements showed that ozone-damaged cantaloupe (Cucumis melo L.) leaves had lower water contents and higher reflectance than nondamaged leaves. Cantaloupe plants with lightly, severely, and very severely ozone-damaged leaves were distinguishable from nondamaged plants by reflectance measurements in the 1.35-2.5-micron near-IR water absorption band. Ozone-damaged leaf areas were detected photographically 16 hours before the damage was visible.

  19. Chloroxyanion Residues in Cantaloupe and Tomatoes after Chlorine Dioxide Gas Sanitation.

    Science.gov (United States)

    Smith, D J; Ernst, W; Herges, G R

    2015-11-04

    Chlorine dioxide gas is effective at cleansing fruits and vegetables of bacterial pathogens and(or) rot organisms, but little data are available on chemical residues remaining subsequent to chlorine gas treatment. Therefore, studies were conducted to quantify chlorate and perchlorate residues after tomato and cantaloupe treatment with chlorine dioxide gas. Treatments delivered 50 mg of chlorine dioxide gas per kg of tomato (2-h treatment) and 100 mg of gas per kg of cantaloupe (6-h treatment) in sealed, darkened containers. Chlorate residues in tomato and cantaloupe edible flesh homogenates were less than the LC-MS/MS limit of quantitation (60 and 30 ng/g respectively), but were 1319 ± 247 ng/g in rind + edible flesh of cantaloupe. Perchlorate residues in all fractions of chlorine dioxide-treated tomatoes and cantaloupe were not different (P > 0.05) than perchlorate residues in similar fractions of untreated tomatoes and cantaloupe. Data from this study suggest that chlorine dioxide sanitation of edible vegetables and melons can be conducted without the formation of unwanted residues in edible fractions.

  20. Volatile compounds profile of fresh-cut peki fruit stored under different temperatures Perfil dos compostos voláteis do pequi minimamente processado armazenado sob diferentes temperaturas

    Directory of Open Access Journals (Sweden)

    Clarissa Damiani

    2009-06-01

    Full Text Available The objective of this work was to identify and verify the influence of time and temperature on the volatile compounds profile of fresh cut peki. Peki fruits were washed, sanitized, their kernels were extracted, and they were packaged and stored for 15 days at 0, 5, and 10 °C and 6 days at 22 °C. The volatiles compounds were analyzed by GC - MS. Ethyl hexanoate and ethyl octanoate were found in higher percentages, 63 and 16.3%, respectively. The determined volatiles were not influenced by the storage period. Hexanoic acid, ethyl 2-octenoate and ethyl decanoate were not influenced by the different temperatures. The temperatures 0, 5, and 10 °C did not influence ethyl hexanoate, ethyl 2-hexenoate and ethyl octanoate either. In addition, the temperatures 5, 10, and 22 °C did not influence ethyl hexanoate, cis-β-ocimene and ethyl octanoate. The temperature of 22 °C determined higher percentages of ethyl hexanoate and lower percentages of ethyl octanoate, in comparison to the temperature of 0 °C, and higher percentages of ethyl 2-hexenoate in comparison to the temperatures of 0, 5, and 10 °C. The temperature of 5 °C determined higher percentage of cis-β-ocimene when compared with the temperature of 0 °C. The storage temperatures of 0 and 5 °C were the most appropriate for the conservation.O objetivo do trabalho foi identificar e verificar a influência do tempo e da temperatura sobre o perfil dos compostos voláteis de pequi minimamente processado. O pequi foi lavado, sanificado, seus pirênios extraídos, embalados e armazenados por 15 dias a 0, 5 e 10 °C e 6 dias a 22 °C. Os compostos voláteis foram analisados por CG-EM. Hexanoato de etila e octanoato de etila foram encontrados em porcentagens mais altas, 63 e 16.3% respectivamente. Os voláteis determinados não foram influenciados pelo tempo de armazenamento. Ácido hexanóico, 2-octenoato de etila e decanoato de etila não foram influenciados pelas diferentes temperaturas. As

  1. 壳聚糖涂膜对鲜切菠萝蜜的保鲜作用%Study on Preservation of Fresh-cut Jackfruit by Chitosan Film

    Institute of Scientific and Technical Information of China (English)

    姜秋焕; 叶盛权; 叶春海; 吕庆芳; 韩锐

    2012-01-01

    本文通过壳聚糖对鲜切菠萝蜜进行涂膜处理,研究保质期内还原糖含量、总酸含量、水分含量的变化,分析壳聚糖涂膜对干苞和湿苞菠萝蜜的保鲜效果.结果表明:在3±1℃的条件下贮藏15 d,涂膜鲜切菠萝蜜的还原糖的变化速率较小,均小于未处理组.涂膜湿苞和干苞的还原糖含量分别降低了3.58%和3.81%,而未处理组还原糖含量降低了4.77%.贮藏到第6d时,涂膜处理的湿苞和干苞含水量都达到最低值,对照组的含水量为65.96%,湿苞和干苞的含水量分别为72.60%和73.81%,总酸量分别降低了0.13%和0.15%,未处理组总酸含量降低了0.23%.壳聚糖涂膜处理能够延缓菠萝蜜的后熟,对湿苞的保鲜效果优于对干苞的保鲜效果.%The effect of chitosan film on the preservation of fresh-cut jackfruit was studied. The change of reducing sugar content, total sugar content and water content was studied, and the effect of chitosan film on the preservation of dry and wet jackfruit was analyzed. It illustrated that the variation of reducing sugar treated jackfruit was less than that of untreated ones under the condition of storage at 3±1 °C for 15 days. Reducing sugar contents of wet and dry decreased by 3.58% and 3.81%, respectively, while that of uncoated group reduced by 4.77%. Water content of wet and dry jackfruit coated was lowest in the sixth day. Water content of uncoated group was 65.96%, and that of wet and dry jackfruit was respectively 72.06% and 73.81 %. And total acid content of these respectively decreased by 0.13% and 0.15%. Total acid content of uncoated group was reduced by 0.23%. Chitosan coating could delay the ripening of jackfruit, and the preservation of wet jackfruit coated with chitosan was better than that of dry jackfruit.

  2. Active packaging for fresh-cut iceberg lettuce (Lactuca sativa L. / Embalagem ativa para alface americana (Lactuca sativa L. minimamente processada

    Directory of Open Access Journals (Sweden)

    Fábio Yamashita

    2010-09-01

    Full Text Available The minimal processing of horticultural products endears the raw material and is convenient to the consumer due to the facility for preparing and consuming. The objective of this work was to develop an active packaging for fresh-cut iceberg lettuce (Lactuca sativa L. to increase its shelf life. Minimally processing methodology was defined and the product quality was determined by sensorial, physico-chemical and microbiological analysis. The lettuce tree was selected, trimmed, pre-washed, soaked in sanitized water (100ppm of active chlorine for 15 minutes and centrifuged. The lettuce leafs were packed in polypropylene pots with a sachet containing 1-methylcyclopropene (1-MCP and sealed with biodegradable starch film. Soon after the processing, the product was stored at 4oC for 12 days. Periodically samples were evaluated in terms of appearance and purchase intention, soluble solids and vitamin C contents, pH, texture, color, weight loss and total count of mesophilic and psicotrofic microorganisms, lactic bacteria, mould and yeast. Using 1-MCP in sachet format did not increase the lettuce shelf life but the minimal processing combined with packaging sealed with biodegradable film is practicable as the product showed good sensorial acceptance, low microbiological counts and shelf life of 5 days at 4oC.O processamento mínimo de produtos hortícolas agrega valor à matéria-prima e são convenientes ao consumidor, devido à facilidade de preparo e consumo. O objetivo do trabalho foi desenvolver uma embalagem ativa para alface americana (Lactuca sativa L. minimamente processada visando o aumento da vida útil. Foi definida uma metodologia de processamento mínimo e a qualidade do produto foi acompanhada através de avaliação sensorial, físico-química e microbiológica. As cabeças de alface foram desfolhadas, selecionadas, pré-lavadas, sanificadas (100 ppm de cloro ativo por 15 minutos e centrifugadas. As folhas foram acondicionadas em potes de

  3. Effects of Different Pretreatments on Micorganism of Fresh-cut Ananas comosus%预处理方法对鲜切菠萝微生物的影响

    Institute of Scientific and Technical Information of China (English)

    邵远志; 李雪萍; 贾文君; 李雯

    2011-01-01

    为保持和改善鲜切菠萝的贮藏品质,以‘巴厘’菠萝为试材,研究不同预处理方法(对照,有机酸,漂烫和有机酸+漂烫)对鲜切菠萝微生物的影响.结果表明:各处理的大肠菌群发生较少且总数极低;在对霉菌的影响上,漂烫处理的抑制效果最明显,至贮藏末期,其霉菌总数仅为CK的1/10,其次是综合处理;鲜切菠萝的酵母菌含量随着贮藏时间的延长不断增多,对照处理上升最快,其次是有机酸处理,而漂烫处理和综合处理的增加缓慢,至贮藏末期(11天),分别比对照低1.7× 106 cfu/g和1.5×106 cfu/g,处理间差异极显著(P<0.01);鲜切菠萝的菌落总数不断增加,对照处理上升最快,其次是有机酸处理,漂烫处理的增加最慢.说明霉菌、酵母菌是鲜切菠萝的主要微生物,漂烫处理能够较显著地抑制鲜切菠萝霉菌、酵母菌和菌落总数的上升,防止果实腐烂变质,而对照和单独酸处理在鲜切菠萝品质保持方面的效果较差.%In order to maintain and improve the storage quality of fresh-cut Ananas comosus, Ananas comosus 'Bali' was used to investigate the effects of different pretreatments (control, organic acid, blanching and organic acid combined with blanching) on micorganism during storage. The results showed that there were fewer and lower number of coliform bacteria in storage of fresh-cut pineapple; for the impact of mold, the effect of blanching was the most obvious, the number of fungus was only 1/.10 of control when the day 5, followed by the integrated treatment. With the extension of storage time, the yeast content of fresh-cut pineapple increased, the yeast increasing of control treatment was the fastest, followed by organic acid treatment, while, the yeast increasing of blanching and integrated treatments were most slowly, at the end of storage (11 d), the yeast contents of blanching and integrated treatments were lower 1.7xl06cfu/g and 1.5xl06cfu/g than the

  4. Studied on the Best Conditions of Fresh-cut Sweet Peppers Storage with Modified Atmosphere Packaging%气调包装保鲜鲜切甜椒最优条件的研究

    Institute of Scientific and Technical Information of China (English)

    高元元

    2012-01-01

    鲜切果蔬具有品质新鲜、食用方便、营养丰富等特点.其生产过程不进行剧烈的加热灭菌和杀酶防褐等处理,且产品包装时不是绝氧的,故产品是“新鲜”的.与原始性状的果蔬相比,它既新鲜洁净又方便省时,具有广阔的发展前途.为了提高鲜切甜椒的贮藏保鲜品质.根据包装袋厚度、温度和装载量三个因素设计正交试验表,通过感官评定、褐变指数、货架期实验得出气调包装保鲜鲜切甜椒的最佳组合.实验表明,最好的组合为0.02mmPE袋(30×40cm),5℃,200g装载量,使鲜切甜椒的货架期达到258h,为实验中的最高值.为鲜切甜椒气调包装保鲜提供了一种简便易行的方法,而且为气调包装在其它鲜切果蔬保鲜方面实现产业化开发应用提供理论和实践的依据.%Fresh-cut fruits and vegetables are charactered by good fresh quality and eating convenience with rich nutrition. Its production process doesn't carry on fierce heated up antiseptic and killed the enzyme to inhibit browning and so on, also when product packaging is not certainly the oxygen isolation, therefore the product is "fresh". Through the comparison with the original characters of fruits and vegetables, they were both fresh and facilitation time-saving, and had a broad development future. It was shown in this study that the quality of fresh-cut sweet peppers was enhanced by storing at PE films. The organoleptic evaluation, browning index and shelf life were evaluated. Through the experiment the best condition of modified atmosphere packaging was obtained which maintained freshness of fresh-cut sweet peppers. The experiment indicated that, the best condition was the 0.02mm PE film (30x40cm), 5℃, 200g packaging capacity. Fresh-cut sweet peppers' shelf-life to achieve 258h was maximum in experiment. The research provided one method which was simple and easy for fresh-cut sweet peppers' modified atmosphere packaging, and supplied the

  5. Quality attributes and microbial survival on whole cantaloupes with antimicrobial coatings containing chitosan, lauric arginate, cinnamon oil and ethylenediaminetetraacetic acid.

    Science.gov (United States)

    Ma, Qiumin; Zhang, Yue; Critzer, Faith; Davidson, P Michael; Zhong, Qixin

    2016-10-17

    Cantaloupes are susceptible to microbiological contamination in pre- or postharvest environments. Novel intervention strategies, such as antimicrobial coatings, are needed to improve the microbiological safety of cantaloupes. The objective of this study was to prepare whole cantaloupes coated with mixtures containing chitosan, lauric arginate (LAE), cinnamon oil (CO), and ethylenediaminetetraacetic acid (EDTA) and determine survival characteristics of inoculated foodborne pathogens during storage as well as cantaloupe quality attributes. Chitosan coating with 0.1% LAE, 0.1% EDTA, and 1% CO was the most effective for inactivating foodborne pathogens inoculated on cantaloupes. This coating caused a >3logCFU/cm(2) reduction of Escherichia coli O157:H7 and Listeria monocytogenes immediately after coating and reduced Salmonella enterica to below the detection limit during a 14-day storage. Total molds and yeasts also were reduced to the detection limit by the coating. The redness and yellowness of uncoated cantaloupes were significantly higher than coated ones from day 6. The firmness of uncoated cantaloupes and those coated with chitosan only was significantly lower than other treatments from day 10. No significant differences were found in total soluble solids content or weight loss between coated and uncoated cantaloupes. Results showed the potential benefits of applying the coating mixtures to improve the quality and microbiological safety of cantaloupes.

  6. Effect of Chitosan Coating on the Quality of Fresh-cut Pumpkin(Cucurbita Moschata) during Storage%壳聚糖涂膜对鲜切南瓜贮藏品质的影响

    Institute of Scientific and Technical Information of China (English)

    张丹丹; 杨绍兰; 吴昊; 张宏斌; 王成荣

    2012-01-01

    Fresh "MiBen" pumpkins were subjected to coating with chitosan at different concentrations (0.5%, 1.0%, 1.5%)and subsequent storage at 4 ℃ in order to examine the fresh-keeping effect of chitosan coating on fresh-cut pumpkin. During the storage, changes in polysaccharose, carotenoid and total phenol contents, ethylene production, weight loss rate, firmness and the activity of PAL and POD of fresh-cut pumpkin were measured. Results showed that chitosan coating could delay the reductions of firmness, polysaccharose, carotenoid and total phenol contents, and also could delay the increase of ethylene production, obviously enhance PAL and POD activities, reduce weight loss rate, and substantially extend the shelf life of fresh-cut pumpkin, especially at a concentration of 1.0%.%以新鲜的“蜜本”南瓜(Cucurbita moschata)为试验材料,探讨不同质量分数(0.5%、1.0%、1.5%)壳聚糖涂膜液处理对鲜切南瓜贮藏品质的影响.结果表明:采用壳聚糖涂膜液处理,不同程度地延缓了鲜切南瓜乙烯释放量的增加和硬度的下降,阻止了多糖和类胡萝卜素的减少,抑制了POD、PAL酶活性的下降和总酚含量的降低.其中以质量分数为1.0%壳聚糖涂膜液处理的效果最好,有效地保持了鲜切南瓜贮藏期间的品质.

  7. Integration of antimicrobial pectin-based edible coating and active modified atmosphere packaging to preserve the quality and microbial safety of fresh-cut persimmon (Diospyros kaki Thunb. cv. Rojo Brillante).

    Science.gov (United States)

    Sanchís, Elena; Ghidelli, Christian; Sheth, Chirag C; Mateos, Milagros; Palou, Lluís; Pérez-Gago, María B

    2017-01-01

    The greatest hurdle to the commercial marketing of fresh-cut fruits is related to their higher susceptibility to enzymatic browning, tissue softening, and microbial growth. The aim of this study was to test the efficacy of a pectin-based edible coating and low oxygen modified atmosphere packaging (MAP) to control enzymatic browning and reduce microbial growth of fresh-cut 'Rojo Brillante' persimmon. The survival of Escherichia coli, Salmonella enteritidis and Listeria monocytogenes artificially inoculated on fresh-cut fruit was also assessed. The pectin coating was amended with 500 IU mL(-1) nisin (NI) as antimicrobial agent and 10 g kg(-1) citric acid and 10 g kg(-1) calcium chloride as anti-browning and firming agents, respectively. Persimmon slices were dipped in the coating or in water (control) and packed under 5 kPa O2 (MAP) or in ambient atmosphere for up to 9 days at 5 °C. Microbial growth, package gas composition, colour, firmness, polyphenol oxidase activity, visual quality and overall sensory flavour of persimmon slices were measured during storage. Coating application combined with active MAP significantly reduced the CO2 emission and O2 consumption in the package. The coating was effective in reducing browning and also inhibited the growth of mesophilic aerobic bacteria. Coating also reduced the populations of E. coli, S. enteritidis and L. monocytogenes. The combination of the pectin-based edible coating and active MAP proved to be the most effective treatment to maintain the sensory and microbiological quality of persimmon slices for more than 9 days of storage. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  8. Effects of different washing agents on the preservation of fresh-cut lettuce%清洗方式对鲜切生菜保鲜效果的影响

    Institute of Scientific and Technical Information of China (English)

    林永艳; 谢晶; 朱军伟; 罗爱琼

    2012-01-01

    Static electricity, ozone, sodium hypochlorite, brine electrolysis and tap-water were used to clean the fresh-cut lettuce, and the quality changes during storage were studied. It was shown that five kinds of washing agents had little effect on the weight loss rate of fresh-cut lettuce. Ozone, sodium hypochlorite, brine electrolysis treatment can delay the decrease of Vc , chlorophyll content in fresh-cut lettuce significantly, and maintaining good sensory quality in the preservation. In the above five kinds of washing agents, ozone treatment was the best method, and it keeps commodity value of lettuce at the 12lh days.%以静电水、臭氧水、次氯酸钠水、电解水、自来水对生菜切割后进行处理,研究不同处理方式对贮藏过程中其品质变化的影响.结果表明,这5种处理方式对鲜切生菜失重率的影响不大;臭氧水、次氯酸钠水、电解水处理能够显著延缓鲜切生菜VC、叶绿素含量的下降,在贮藏过程中保持了较好的感官品质.在上述5种处理方式中臭氧水对后期的保鲜效果最佳,是切割蔬菜贮藏前推荐的处理方式,鲜切菜产品贮藏到第12天仍有商品价值.

  9. Experimetal study on monitoring ozonated water disinfection of fresh-cut fruit and vegetables by ORP%用ORP监控鲜切果蔬臭氧水消毒的实验研究

    Institute of Scientific and Technical Information of China (English)

    李尤; 刘钟阳; 都健

    2011-01-01

    研究了用氧化还原电位(ORP)监控臭氧水对鲜切果蔬的消毒灭菌过程,通过不同ORP的臭氧水消毒实验发现,将鲜切果蔬浸入ORP超过800mV的臭氧水中超过30s可以使细菌总数下降约2个数量级.通过改变臭氧浓度和水温的方法研究了臭氧水ORP的影响因素,得出了提高臭氧气体浓度和低温制冷有利于制取高ORP臭氧水的结论.结果表明,利用ORP监测臭氧水的消毒能力是可行的.%Monitoring the process of disinfection and sterilization of fresh-cut fruit and vegetables treated with ozonated water by ORP was studied.It was found that the number of total bacterial counts was reduced by the order of about 102 by immerging fresh-cut fruit and vegetables into ozonated water with ORP above 800mV over 30s through ozonated water disinfection and sterilization experiment with different values of ORP.The influence factors of ORP of ozonated water were studied by changing concentration of ozonated and water temperature.It was concluded that increasing the concentration of ozone and lowering the water temperature tend to produce ozonated water with high ORP.The study showed that it was feasible to monitor the ability of disinfection and sterilization of fresh-cut fruit and vegetables with ozonated water by ORP.

  10. 可食性莲子淀粉涂膜对鲜切菠萝品质的影响%Effects of edible lotus seed starch coating on quality of fresh-cut pineapple

    Institute of Scientific and Technical Information of China (English)

    林鸳缘; 郑宝东; 曾绍校; 张帆; 吴树铮

    2011-01-01

    Influence of edible lotus seed starch coating on quality of fresh-cut pineapple was studied. Fresh-cut pineapple was coated with 1%, 2% or 3% lotus seed starch pasting incorporating nisin an a natural antimicrobial agent; placed into plastic trays, and o ver-wrapped with PE film and then stored at (5 ± 1) ℃. Changes in ripening index, juioe leakage, colour, firmness and microbial growth were evaluated over time. The results showed that lotus seed starch coating retarded senescence, browning and softening. It also inhibited the growth of microorganisms effectively. The total microbial count coated with 2%, 3% lotus seed starch could be controlled under 105 (less than 105 was in line with fresh-cut food hygiene requirements) during tea days due to the synergistic effect of lotus seed starch coating and nisin. The results revealed that lotus seed starch coating maintained the quality attributes of fresh-cut pineapple effectively.%分别采用1%、2%、3%不同浓度莲子淀粉膜液(含天然防腐剂nisin)对鲜切菠萝片进行涂膜处理,再装入塑料盒中,用PE薄膜密封,于(5±1)℃贮藏.在贮藏过程中,对鲜切菠萝的成熟度、流汁率、色泽、硬度和细菌菌落总数等相关指标进行评价,研究可食性莲子淀粉涂膜对鲜切菠萝品质的影响.结果表明,涂膜处理能延缓鲜切菠萝的衰老、褐变、软化,有效抑制微生物的生长.2%、3%涂膜处理组贮藏10 d内,莲子淀粉膜与nisin的协同作用可使菌落总数控制在105以下,符合鲜切果蔬的食品卫生要求.因此,采用莲子淀粉涂膜处理能有效保持鲜切菠萝的品质.

  11. Effects of sodium alginate treatment in physiology and biochemistry changes of fresh-cut Xuehua pears%海藻酸钠处理对鲜切雪花梨生理生化的影响

    Institute of Scientific and Technical Information of China (English)

    田密霞; 胡文忠; 刘程惠; 王艳颖; 姜爱丽

    2015-01-01

    目的:研究海藻酸钠涂膜对鲜切雪花梨外观,质地及营养成分的影响。方法以鲜切雪花梨为材料,采用海藻酸钠(1%海藻酸钠+0.15%半胱氨酸+0.3%VC+0.6%醋酸)进行涂膜处理鲜切梨,测定经涂膜处理后的鲜切雪花梨的生理生化指标。结果雪花梨经过鲜切后在4℃和10℃贮藏期间,海藻酸钠涂膜处理明显减轻了鲜切雪花梨的褐变程度,抑制了多酚氧化酶和过氧化物酶的活性,保持较高的硬度、可滴定酸和VC含量,延缓了水分散失。结论海藻酸钠处理较好地保持了贮藏期间鲜切雪花梨的外观和质地。%Objective To research the effects of sodium alginate treatment on appearance, texture and nutritional ingredient of fresh-cut Xuehua pears.Methods Fresh-cut Xuehua pears were used as materials. Physiological and biochemical indicators were measured by sodium alginate (1 % sodium alginate, 0.15 %L-cysteine, 0.3 % VC and 0.6 % acetic acid) treatment on fresh-cut Xuehua pears.Results During storage at 4 and 10℃, the sodium alginate treatment could alleviated browning, inhibited polyphenol oxidase (PPO) and peroxidase (POD) activity, maintained a high firmness, Vc content and titratable acid content.Conclusion The data suggested that sodium alginate composite film could remain quality and appearance of the fresh-cut Xuehua pear during storage period.

  12. Effect of Dimethyl Dicarbonate(DMDC) as disinfectant on the quality of Fresh-cut flowering cabbages%DMDC杀菌对鲜切菜心品质的影响

    Institute of Scientific and Technical Information of China (English)

    王惠惠; 王维民; 陈于陇; 徐玉娟; 范梅红

    2013-01-01

    In the paper,the effect of total aerobic plate count and count of total yeasts and molds in the fresh-cut flowering cabbage treated by DMDC was investigated.And the sensory,nutritional quality and browning-related enzymes in fresh-cut flowering cabbage treated by DMDC were also determined at storage.This study aims to evaluate the effect of DMDC on fresh-cut flowering cabbage.It turned out that the total aerobic plate count and count of total yeasts and molds in the fresh-cut flowering cabbage treated by DMDC were significantly reduced (p <0.05).DMDC treatment made negative impact on firmness,color and chlorophyll at early storage of 8d,and had no significant influence on Vc and soluble sugar.However the treatment could reduce the loss of soluble protein and inhibit PPO and POD activities.As shown above,DMDC treatment can effectively reduce the occurrence of microorganisms on the surface of flowering cabbage,delay the browning-related enzymes'activity,and slow down the senescence and maintain the quality of flowering cabbage.%本文以鲜切菜心为原料,研究了二甲基二碳酸盐(DMDC)作为杀菌剂对其细菌、霉菌和酵母菌总数的影响,并通过测定鲜切菜心在贮藏期间外观品质、营养成分及其褐变相关主要酶的变化,对DMDC用于鲜切菜心的杀菌效果进行评价.结果表明:DMDC可以有效减少鲜切菜心中细菌(革兰氏阳性菌)、霉菌和酵母菌总数,对其贮藏前期的硬度、色泽、叶绿素含量的变化有一定影响,但是对Vc和可溶性糖无明显影响;并且可有效减少可溶性蛋白的损失,抑制多酚氧化酶(PPO)、过氧化物酶(POD)的活性.说明DMDC杀菌可以有效杀灭菜心表面微生物,延缓菜心贮藏期褐变相关酶活性的增加和衰老,有利于维持菜心的营养品质.

  13. HPLC法测定鲜切富士苹果中多酚类物质的研究%Quantitative determination of phenolics composition in fresh-cut ‘Fuji’ apples by high performance liquid chromatography

    Institute of Scientific and Technical Information of China (English)

    陈晨; 胡文忠; 姜波; 姜爱丽; 邹宇

    2015-01-01

    目的:分析鲜切富士苹果中多酚成分及含量。方法鲜切苹果多酚采用80%乙醇超声提取,利用高效液相色谱法法分析鲜切苹果中多酚成分,外标法定量分析各多酚组分的含量。结果10种多酚标准品的溶液浓度和检测响应值呈现出良好的线性关系,其相关系数r2均大于0.99,且回收率较超过95%,重复性好。鲜切富士苹果中主要含有绿原酸、表儿茶素、儿茶素、丁香酸和咖啡酸5种多酚物质,其中绿原酸和表儿茶素含量较高,分别为101.02±0.31μg/g和100.80±2.65μg/g。结论鲜切富士苹果富含具有抗氧化活性的多酚成分。%Objective To analyze the phenolics composition of fresh-cut ‘Fuji’ apples.Methods Phenolics were extracted from fresh-cut apples with 80% ethanol. Phenolics composition was analyzed by high performance liquid chromatography (HPLC). An external standard method was used for quantitative analysis.Results The results showed that 10 polyphenols could be separated and the calibrations curves were linear withr2>0.999 and the recovery rate was above 95%. HPLC analysis revealed that the main phenolic compounds in fresh-cut ‘Fuji’ apples were chlorogenic acid followed by chlorogenic acid, epicatechin, catechin, syringic acid and caffeic acid. The concentrations of chlorogenic acid and epicatechin were higher than others, with the values 101.02±0.31μg/g and 100.80±2.65μg/g, respectively.Conclusion Fresh-cut apple is rich in polyphenols with antioxidant activity.

  14. 食前热水处理提高鲜切黄瓜微生物安全性的研究%Improving microbial safety and quality of fresh-cut cucumbers by hot water treatments just before eating

    Institute of Scientific and Technical Information of China (English)

    张甜甜; 李天琪; 王庆国; 王敏

    2013-01-01

    This paper aimed to study the effect of hot water treatment for killing foodborne pathogens on freshcut cucumber while maintaining its freshness.Based on the sensory quality of fresh-cut cucumber after hot water treatment,selected hot water treatment conditions,and further studies of hot water treatment in reducing foodborne pathogens in water and on surface of fresh-cut cucumber were carried out.The results showed that:the high initial concentration numbers of 5.42 and 5.16log CFU/g for Salmonella Typhimurium and Listeria monocytogenes respectively on fresh-cut cucumbers treated by 60℃ 5min heat treatment,were reduced to under detection line,although fresh-cut cucumber antioxidant value reduced and cell membrane permeability increased,but the measured hardness did not change,maintaining fresh sensory and good eating value.%探讨食前热水处理能否有效杀灭鲜切黄瓜表面的单增李斯特菌和鼠伤寒沙门氏菌这两种食源性致病菌,同时又保持其新鲜度.实验首先根据热水处理后鲜切黄瓜的感官品质,筛选了其耐热条件,进一步研究了热处理对水中和鲜切黄瓜表面食源性致病菌降低的效果.结果表明,经60℃5min热水处理,鲜切黄瓜上的鼠伤寒沙门氏菌、单增李斯特菌数量从高起始染菌浓度5.42、5.161og CFU/g,降低到检测线(0.6log CFU/g)以下,鲜切黄瓜的抗氧化值降低、细胞膜透性有所提高,但其测定硬度变化不大,感官上仍鲜脆,仍具有较好食用价值.

  15. Enhanced Virulence Gene Activity of Agrobacterium in Muskmelon (Cucumis melo L. cv. ‘Birdie’

    Directory of Open Access Journals (Sweden)

    Abul K.M. MOHIUDDIN

    2011-05-01

    Full Text Available Muskmelon (Cucumis melo L. cultivar ‘Birdie’, was evaluated for its response to the tumorigenic Agrobacterium tumefaciens and the oncogenic A. rhizogenes strains. Stem and petiole of three week-old in vitro-grown muskmelon plants were inoculated with five strains of A. tumefaciens and A. rhizogenes each and observed phenotypic expressions i.e. induction of crown galls and hairy roots. This phenotypic expression was efficaciously increased when virulence gene activity of different strains of two Agrobacterium species was enhanced. Intensive studies on enhancement of virulence gene activity of Agrobacterium found to be correlated to the appropriate light intensity (39.3 μmol m-2 s-1 with a specific concentration of monocyclic phenolic compound, acetosyringone (20 μM. The gene activity was also influenced by several other physical factors e.g. plant tissue type, Agrobacterium species and their strains, and plant tissue-Agrobacterium interaction. Among the different A. tumefaciens strains, LBA4404 showed the best virulence gene activity in both stem and petiole through the formation of higher rate of crown galls. On the other hand, strain 15834 of A. rhizogenes showed better gene activity in stem and 8196 in petiole through the formation of higher rate of hairy roots as well as higher average number of hairy roots. Among the two different types of explants, petiole was more susceptible to both Agrobacterium species. Thus it was concluded that future muskmelon transformation study can efficiently be carried out with LBA4404, 15834 and 8196 strains using petiole explants by adding 20 μM of acetosyringone in the medium.

  16. 清洗方法对鲜切山药贮藏效果的影响%Study on storage effect of fresh-cut yam by different cleaning methods

    Institute of Scientific and Technical Information of China (English)

    董雷; 姚连芳; 高愿军

    2012-01-01

    The cleaning effects were determined by measuring the total numbers of colonies, MDA, weight lost and sensory quality of fresh cut yam, which was processed by using different concentrations of sodium hypochlorite, hydrogen peroxide and citric acid treatment. The results showed: sodium hypochlorite treatment can significantly reduce the total numbers of colonies of fresh-cut yam, but higher concentrations may damage the internal organization, and 0. 6% sodium hypochlorite solution was better, and then was hydrogen peroxide, citric acid was the worst.%采用不同浓度的次氯酸钠、双氧水和柠檬酸对鲜切山药进行处理,通过测定鲜切山药储藏期间的菌落总数、丙二醛含量、失重率以及感官品质来衡量清洗效果.结果表明:次氯酸钠处理可以明显降低鲜切山药的菌落总数,但浓度过高会破坏山药的内部组织,不利于其储藏;0.6%的次氯酸钠溶液处理效果较佳,双氧水次之,柠檬酸最差.

  17. Foliar Fertilization of Muskmelon: Effects of Potassium Source on Market Quality and Phytochemical Content of Field-Grown Fruit

    Science.gov (United States)

    Muskmelon [Cucumis melo L. (Reticulatus Group)] fruit quality attributes such as sweetness, aroma, and texture are directly related to potassium (K)-mediated processes. However, during fruit growth and maturation, soil K supply alone is often inadequate to satisfy K requirements. Previous studies ...

  18. [Impacts of root-zone hypoxia stress on muskmelon growth, its root respiratory metabolism, and antioxidative enzyme activities].

    Science.gov (United States)

    Liu, Yi-Ling; Li, Tian-Lai; Sun, Zhou-Ping; Chen, Ya-Dong

    2010-06-01

    By using aeroponics culture system, this paper studied the impacts of root-zone hypoxia (10% O2 and 5% O2) stress on the plant growth, root respiratory metabolism, and antioxidative enzyme activities of muskmelon at its fruit development stage. Root-zone hypoxia stress inhibited the plant growth of muskmelon, resulting in the decrease of plant height, root length, and fresh and dry biomass. Comparing with the control (21% O2), hypoxia stress reduced the root respiration rate and malate dehydrogenase (MDH) activity significantly, and the impact of 5% O2 stress was more serious than that of 10% O2 stress. Under hypoxic conditions, the lactate dehydrogenase (LDH), alcohol dehydrogenase (ADH), pyruvate decarboxylase (PDC), superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities and the malondialdehyde (MDA) content were significantly higher than the control. The increment of antioxidative enzyme activities under 10% O2 stress was significantly higher than that under 5% O2 stress, while the MDA content was higher under 5% O2 stress than under 10% O2 stress, suggesting that when the root-zone oxygen concentration was below 10%, the aerobic respiration of muskmelon at its fruit development stage was obviously inhibited while the anaerobic respiration was accelerated, and the root antioxidative enzymes induced defense reaction. With the increasing duration of hypoxic stress, the lipid peroxidation would be aggravated, resulting in the damages on muskmelon roots, inhibition of plant growth, and decrease of fruit yield and quality.

  19. Application of edible active films coatings on preservation of fresh-cut fruits and vegetables%可食性活性涂膜在鲜切果蔬保鲜中的应用

    Institute of Scientific and Technical Information of China (English)

    萨仁高娃; 胡文忠; 修志龙; 姜爱丽; 冯可

    2015-01-01

    可食性涂膜是一种由天然可食性材料制成的选择透过性薄膜,具有调节果蔬内部气体交换、减少水分损失、降低腐烂率及延长货架期的特性,在果蔬包装及保鲜领域中已引起广泛关注。鲜切果蔬具有新鲜、方便、快捷等特点,已在全球范围内广泛供应餐饮业及零售业。可食性涂膜作为多种食品添加剂的载体常应用于生鲜产品中,且将活性添加剂与可食性涂膜结合可以延长鲜切果蔬的货架期,提高果蔬品质,减少果蔬表面致腐及致病菌增长的风险。可食性活性涂膜将作为一种绿色、安全、营养的保鲜技术,并将应用于鲜切果蔬保鲜领域的研究。本文综述了可食性涂膜的分类及其添加的抗菌剂、抗氧化剂、塑形剂、营养素等活性成分在鲜切果蔬保鲜中的应用,旨在开发用于鲜切果蔬保鲜的功能性可食性涂膜。%Edible film is a kind of selectively permeable membrane which is made of natural edible material. It can coordinate the gas exchange, reduce the water loss and the rot rate, and prolong the shelf-life of fruits and vegetables. Edible coating film has gained a wide concern in the fields of food package and food storage. Fresh-cut fruits and vegetables had the characters of fresh, convenient, and rapid, which were widely applied in catering industry and retail industry. Edible coating as carrier of food adding agent were applied in fresh products. It incorporated with active adding agent that would prolong the shelf life, improve quality of fresh-cut fruits and vegetables, and reduce the increasing of pathogenic bacteria. Edible coating had been applied to preservation for fresh-cut fruits and vegetables as a kind of preservation technology of food safety. The application of edible coating classification and adding active ingredient of antimicrobial, antioxidant, nutrient on fresh-cut fruits and vegetables was reviewed in this paper. The

  20. 贮藏温度对鲜切香菜营养成分和抗氧化活性的影响%Effects of storage temperature on nutritional compositions and antioxidant activity of fresh-cut coriander

    Institute of Scientific and Technical Information of China (English)

    韩聪; 李晓安; 高梵; 金鹏; 郑永华

    2015-01-01

    Objective To analyze the effect of different storage temperature on the nutritional compositions and antioxidant activity of fresh-cut coriander.Methods Fresh-cut coriander was cut and placed into preservation boxes, and stored at 4℃ , 10℃ and 20℃ . The changes of ascorbic acid, chlorophyll, soluble sugar, total phenolics, total flavonoids and DPPH radical scavenging activity were investigated.ResultsThe results indicated that cutting induced a fast loss of ascorbic acid, chlorophyll and soluble sugar. Compared with 10℃ and 20℃ , storage temperature of 4℃ significantly decreased the disruption of these nutrients. In addition, cutting also induced the synthesis and accumulation of phenolic and flavone compounds, enhanced its DPPH radical scavenging activity, and improved the antioxidant activity of coriander. Compared with 4℃ and 10℃ , the content of phenolic and flavone compounds and antioxidant activity in fresh-cut coriander were higher at 20℃ .Conclusion Low storage temperature can preserve the nutritional quality of fresh-cut coriander, while higher temperature can induce the improvement of antioxidant activity of fresh-cut coriander.%目的:分析不同温度贮藏对鲜切香菜营养成分和抗氧化活性的影响。方法将香菜进行切割处理后装入保鲜盒,在4℃、10℃和20℃下贮藏,测定鲜切香菜抗坏血酸、叶绿素、可溶性糖、总酚、总黄酮含量和DPPH自由基清除率的变化。结果切割伤害会促进香菜抗坏血酸、叶绿素和可溶性糖含量迅速下降,与10℃和20℃相比,4℃低温贮藏的香菜抗坏血酸等营养成分的消耗速率最低。此外,切割还会诱导香菜多酚和类黄酮类物质的合成、积累及DPPH自由基清除率的上升,从而增强其抗氧化活性。与4℃和10℃相比,20℃条件下香菜的多酚类和类黄酮类物质积累最多,抗氧化活性最强。结论低温贮藏有利于维持鲜切香菜的营养成分,而高温贮藏会

  1. Effect of Nano-chitosan Coating on Quality of Fresh-cut Zizania latifolia%纳米壳聚糖涂膜对鲜切茭白品质的影响

    Institute of Scientific and Technical Information of China (English)

    周静峰; 罗海波; 王隽; 江凯; 郁志芳

    2013-01-01

    研究了纳米壳聚糖涂膜对鲜切茭白品质的影响.鲜切茭白分别在去离子水(对照)、10g/L壳聚糖或10g/L壳聚糖+1.5 g/L纳米壳聚糖溶液中浸泡3min,自然晾干包装后于1±0.5℃下贮藏12d.贮藏过程中每3d测定鲜切茭白的白色指数(WI)、硬度、失重率及木质素、还原糖、抗坏血酸含量,PAL、SOD、CAT和POD活力.结果显示,纳米壳聚糖涂膜显著抑制了鲜切茭白WI值的下降和木质素含量的增加,维持了相对高的硬度及还原糖和抗坏血酸含量;贮藏12d后失重率为1.12%; PAL和POD活性显著低于对照(P<0.05),SOD和CAT活性显著高于对照(P<0.05).以上结果表明,纳米壳聚糖涂膜能有效延缓鲜切茭白褐变和木质化,提高抗氧化酶类活性,提示纳米壳聚糖涂膜具有商业上控制鲜切茭白品质劣变的潜在价值.%The effect of nano-chitosan coating on the quality of fresh-cut Z.latifolia was investigated.Fresh-cut Z.latifolia slices were dipped into deionised water (the control),10 g/L chitosan or the mixture of 10 g/L chitosan and 1.5 g/L nano-chitosan for 3 min,and then dried,packaged and finally stored for 12 days at 1±0.5 ℃.Changes in whiteness index (WI),firmness,weight loss,lignin,reducing sugar and ascorbic acid contents,phenylalanine ammonia-lyase (PAL),superoxide dismutase (SOD),eatalase (CAT) and peroxidase (POD) activities were evaluated at intervals of two days.The results showed that the nano-chitosan coating significantly inhibited the decline of WI value and the increase of lignin content,maintained relatively high firmness,reducing sugars and ascorbic acid contents of fresh-cut Z.latifolia.After a 12-day storage at 1±0.5 ℃,the weight loss of the fresh-cut Z.latifolia slices was 1.12%.The treatment also inhibited the activities of PAL and POD but promoted SOD and CAT activities compared with the control.The present findings indicated that the nano-chitosan coating could inhibit browning and

  2. Efeito do tipo de corte e sanificantes no amaciamento de pequi (Caryocar brasiliense Camb. minimamente processado Effect of the cut type and sanitizers on the softening of fresh cut pequi fruit (Caryocar brasiliense Camb.

    Directory of Open Access Journals (Sweden)

    Luiz José Rodrigues

    2007-12-01

    Full Text Available Frutos e hortaliças minimamente processados devem apresentar atributos de conveniência e qualidade do produto fresco. Com o presente trabalho, objetivou-se avaliar a influência dos sanificantes hipoclorito de sódio (NaClO 50 ppm e 100 ppm e peróxido de hidrogênio (H2O2 4% e 6%, sobre os processos envolvidos no amaciamento de pequi (Caryocar brasiliense Camb. minimamente processado submetido a dois tipos de processamento: "caroço fatiado" e "caroço inteiro" e armazenado a 6 ± 1ºC e 90% a 95% UR, durante 15 dias. A cada três dias foram avaliados: perda de massa, firmeza, pectina total, pectina solúvel, atividade de pectinametilesterase (PME e atividade de poligalacturonase (PG. O pequi minimamente processado apresentou perda de massa e decréscimo de firmeza ao longo do período de armazenamento, concomitante ao aumento da atividade da enzima poligalacturonase, bem como solubilização de substâncias pécticas. Não foi verificada atividade de PME no pequi minimamente processado avaliado. Os caroços fatiados apresentaram maior teor de pectina solúvel, do 3° ao 6° dia e atividade da enzima poligalacturonase, do 3° ao 12° dia de armazenamento, em relação aos caroços inteiros. A sanificação com NaClO 50 ppm e 100 ppm, H2O2 4% e 6% determinou maior solubilização péctica em pequis minimamente processados, ao longo do armazenamento, não sendo observada influência dos sanificantes sobre as variáveis firmeza, perda de massa e atividade de poligalacturonase.Fresh cut fruits and vegetables should present convenience and quality features of the fresh produce. The present work aimed to evaluate the influence of the sanitizers 50ppm and 100ppm sodium hypochloride (NaClO and 4% and 6% hydrogen peroxide (H2O2 on the involved processes in the softening of fresh cut pequi fruit (Caryocar brasiliense Camb. submitted to two types of processing: "sliced stone" and "whole stone" stored at 6 ± 1°C and 90% to 95% of RH during 15 days

  3. Research progress of storage of fresh-cut fruits and juices by natural antimicrobials%天然防腐剂在鲜切水果和果汁保鲜中的研究进展

    Institute of Scientific and Technical Information of China (English)

    王怡; 陆利霞; 熊晓辉

    2012-01-01

    With improved living standard , the demand for low - calorie foods are increasing. The consumption of ready - to - eat fresh - cut fruits and fruit juices is gradually increased because of the attention to the food safety. Due to damaged tissue and form, fresh -cut fruits and fruit juices are easy polluted caused by pathogenic and spoilage microorganisms. If treated under inappropriate manipulation arid storage conditions, the product may be subject to microhm! diseases and spoilage. Quality loss in fresh -cut fruits and unpasteurized juices may be caused by microbiological, en-isymatic, chemical, or physical changes. Among these, microbiological cause is particularly important; first, micro-bial toxins or pathogenic microorganisms in the product are harmfal to the health of consumers; second , mierobial spoilage may incur economic losses to consumers. The use of antiseptic can effectively reduce mierobial pollution and enhance safety. Natural food additives can assure safety and maintain quality characteristics. Studies on the use of natural substances to prevent fresh - cut fruits and unpasteurized juices from microbiological spoilage have been significantly increased in recent years. This review summaries the different studies on the antimicrobial effectiveness to pathogenic and spoilage microorganisms in fresh - cut fruits and fruit juices by natural antimicrobials of animal, plant and mierobial origin%随着国民生活水平的提高,人们对低热量食品的需求不断增大,即食鲜切水果和果汁的消费也逐渐增加,它们的安全性越来越受到人们的重视.鲜切水果和果汁由于组织和形态被破坏极易受到病原微生物和腐败微生物的污染,如果加工或储存条件不当,极易造成微生物致病和腐败.微生物学、酶学、化学或物理学变化均能引起鲜切水果与未高温消毒果汁的质量损失.其中,微生物造成的损失非常重要,有两方面原因:一是微生物毒素或病原微

  4. Application of preservation technologies in fresh-cut fruits and vegetables%应用于鲜切果蔬中的保鲜技术研究进展

    Institute of Scientific and Technical Information of China (English)

    纪懿芳; 胡文忠; 姜爱丽

    2015-01-01

    Fresh-cut fruits and vegetables are increasingly favored by consumers, their sales increased by their convenience, rich nutrition and great freshness characteristics. Fresh-cut fruits and vegetables are also known as cut fruits and vegetables, semi processed fruits and vegetables, fruits and vegetables such as conditioning, usually refer to change vegetables, fruit, and physical shape, but still continue in its state of fresh fruit products or produce mixed products. The production process generally goes through cleaning, grading, trimming, segmentation, washing, drying, packaging, storage and distribution, available to consumers directly edible or by restaurants cooking. Preservation technologies in fresh-cut fruits and vegetables significantly affect sensory aspects such as color, smell, texture, flavor, and tissue. This paper summarized the preservation technologies of fresh-cut fruits and vegetables, such as physical, chemical, biological and combinatorial preservation technologies for fresh-cut fruits and vegetables, which would provide the further understanding of current problems and guidance of future research directions, and prospect for future developments presented.%鲜切果蔬因其方便、健康、新鲜等特点日益受到人们的青睐,销售量逐年增加。鲜切果蔬又称为切割果蔬、半加工果蔬、调理果蔬等,通常是指改变了蔬菜、水果物理形状、但仍然保持其新鲜状态的果蔬制品或果蔬混合产品。其生产过程一般要经过清洗、分级、修整、切分、洗涤、干燥、包装、贮存、配送等工序,可供消费者直接食用或餐饮业使用。鲜切果蔬保鲜技术对果蔬的色泽、气味、质地、营养成分、组织状态等感官方面得以最大的保留,减少果蔬因经过清洗、去皮、等机械处理过程导致的品质改变。本论文主要对现阶段鲜切果蔬的保鲜技术研究进展进行综述,其主要技术包括物理、化学和综

  5. 臭氧水浓度对鲜切菠萝品质的影响%Effects of Ozone Water on Microorganism and Quality of Fresh-cut Pineapple

    Institute of Scientific and Technical Information of China (English)

    覃海元; 胡冰冰; 梁金姐; 韦春平

    2011-01-01

    The fresh-keeping effect of ozone water on fresh-cut pineapple was studied in this paper.Fresh-cut pineapple slices were soaked in 0、0.87、1.1、1.4、1.8 mg/L of ozone water for 2 min respectively,then packed in plastic trays,covered with PE film and stored at 5 ℃ for 0~9 days.The bacterial count,ascorbic acid,weight loss rate,soluble solids and color were measured respectively at 3-day interval during cooling storage.The results showed that the bacterial count of fresh-cut pineapple treated with 0、0.87、1.1、1.4、1.8 mg/L of ozone water were 5.3×105、9.3×104 、2.6×104 、3.6×103 、2.5×103 CFU/g respectively on the first day,and 4.7×108、2.4×107 、4.5×106 、4.1×105 、2.3×105 CFU/g On the 9th day.Ozone water teatment could inhibite browning,reduce weight loss and total soluble solid consumption,and had some effects on ascorbic acid content of fresh-cut pineapple.Ozone water treatment could extend the shelf life of fresh-cut pineapple.%为研究臭氧水浓度对鲜切菠萝的保鲜效果,分别采用0 mg/L、0.87 mg/L、1.1 mg/L、1.4 mg/L、1.8 mg/L的臭氧水浸泡处理鲜切菠萝2 min,装在塑料托盘中并用聚乙烯保鲜膜包裹,在冷藏(5℃)过程中每3 d测定鲜切的菌落总数、抗坏血酸、失重率、可溶性固形物和色泽。结果表明:经0 mg/L、0.87 mg/L、1.1 mg/L、1.4 mg/L、1.8 mg/L臭氧水处理的鲜切菠萝的菌落总数,在处理当天分别为5.3×105 CFU/g、9.3×104 CFU/g、2.6×104 CFU/g、3.6×103 CFU/g、2.5×103 CFU/g;第9 d分别为4.7×108 CFU/g、2.4×107 CFU/g、4.5×106 CFU/g、4.1×105 CFU/g、2.3×105 CFU/g;臭氧水处理可以抑制鲜切菠萝的褐变,减少失重和可溶性固形物消耗,对还原型抗坏血酸含量有一定影响。臭氧水处理可以延长鲜切菠萝的保质期。

  6. Effect of mild heat pre-treatment on storage quality of fresh-cut Arctium lappa%热处理对鲜切牛蒡贮藏品质的影响

    Institute of Scientific and Technical Information of China (English)

    郑义; 李勇; 高兆建; 孙烨桐; 赵海睿

    2015-01-01

    Objective Toevaluate the effect of heat pre-treatment on storage quality of fresh-cutArctium lappaby central composite design (CCD)/response surface methodology (RSM).Methods Fresh-cutArctium lappa were treated under different time and temperature combinations and placed on simulated shelf at 23℃ ±2℃ for 5 d, then L* value, rate of weight loss and content of vitamin C of fresh-cutArctium lappa were measured. The adequacy of model equations for predicting the optimum response values were verified by the validated data.Results When the heat pre-treatment parameters were controlled at temperature of 46.5℃ and the processing time of 28.8 min, the L* value, rate of weight loss and content of vitamin C of fresh-cut Arctium lappa were 66.07, 0.78% and 6.16 mg/100 g, respectively. The experimental values agreed closely with the theoretical values predicted by RSM models, indicating that the models were adequate for the produce process.Conclusion Heat pre-treatment could effectively delay quality storage degradation of fresh-cut Arctium lappa.%目的:采用星点设计-响应面法研究了热处理对鲜切牛蒡贮藏品质的影响。方法对鲜切牛蒡进行不同时间和不同温度的热处理,处理后的牛蒡切片置于23℃±2℃条件下5 d(模拟货架期),对货架结束后的牛蒡色泽L*值、失重率和维生素C(VC)含量进行测定。采用响应面法建立了牛蒡色泽L*值、失重率和VC含量的二次多项数学模型,并验证了模型的有效性。结果热处理鲜切牛蒡的最佳处理温度为46.5℃,处理时间28.8 min,在此条件下,牛蒡色泽L*值、失重率和VC含量理论值分别为66.07、0.78%和6.16 mg/100 g。实际测得L*值66.13±1.7,失重率(0.79±0.03)%, VC含量(6.12±0.12) mg/100 g,与预测值基本一致,表明所建模型具有较好的预测性能,可用于指导生产实践。结论热处理可有效降低鲜切牛蒡贮藏品质的下降。

  7. Survival and growth of Listeria monocytogenes on whole cantaloupes is dependent on site of contamination and storage temperature

    Science.gov (United States)

    Whole cantaloupes (Cucumis melo L), marketed as ‘Rocky Ford’, were implicated in a large multi-state outbreak of listeriosis in the United States in 2011; however, survival and growth of Listeria monocytogenes on whole cantaloupes remains relatively unexplored. The research presented here evaluated ...

  8. Inactivation of Listeria monocytogenes, Salmonella spp. and Escherichia coli O157:H7 on cantaloupes by octenidine hydrochloride

    Science.gov (United States)

    This study investigated the efficacy of a new generation disinfectant, namely octenidine dihydrochloride (OH) as wash and coating treatments for reducing Listeria monocytogenes, Salmonella spp., and Escherichia coli O157:H7 on cantaloupe surface. Cantaloupe rind plugs inoculated separately with L. m...

  9. Inactivation of Salmonella enterica and Listeria monocytogenes in cantaloupe puree by high hydrostatic pressure with/without added ascorbic acid

    Science.gov (United States)

    The objective of this research was to evaluate and develop a method for inactivation of Salmonella enterica and Listeria monocytogenes in cantaloupe puree (CP) by high hydrostatic pressure (HHP). Cantaloupe being the most netted varieties of melons presents a greater risk of pathogen transmission. ...

  10. Transfer of Pathogens from Cantaloupe Rind to Preparation Surfaces and Edible Tissue as a Function of Cutting Method.

    Science.gov (United States)

    Shearer, Adrienne E H; LeStrange, Kyle; Castañeda Saldaña, Rafael; Kniel, Kalmia E

    2016-05-01

    Whole and cut cantaloupes have been implicated as vehicles in foodborne illness outbreaks of norovirus, salmonellosis, and listeriosis. Preparation methods that minimize pathogen transfer from external surfaces to the edible tissue are needed. Two preparation methods were compared for the transfer of Listeria monocytogenes, Salmonella enterica serovar Typhimurium LT2, murine norovirus, and Tulane virus from inoculated cantaloupe rinds to edible tissue and preparation surfaces. For the first method, cantaloupes were cut into eighths, and edible tissue was separated from the rind and cubed with the same knife used to open the cantaloupes. For the second method, cantaloupes were scored with a knife around the circumference sufficient to allow manual separation of the cantaloupes into halves. Edible tissue was scooped with a spoon and did not contact the preparation surface touched by the rind. Bacteria and virus were recovered from the rinds, preparation surfaces, and edible tissue and enumerated by culture methods and reverse transcription, quantitative PCR, respectively. Standard plate counts were determined throughout refrigerated storage of cantaloupe tissue. Cut method 2 yielded approximately 1 log lower recovery of L. monocytogenes and Salmonella Typhimurium from edible tissue, depending on the medium in which the bacteria were inoculated. A slight reduction was observed in murine norovirus recovered from edible tissue by cut method 2. The Tulane virus was detected in approximately half of the sampled cantaloupe tissue and only at very low levels. Aerobic mesophilic colony counts were lower through day 6 of storage for buffered peptone water-inoculated cantaloupes prepared by cut method 2. No differences were observed in environmental contamination as a function of cutting method. Although small reductions in contamination of edible tissue were observed for cut method 2, the extent of microbial transfer underscores the importance of preventing contamination of

  11. Effects of Hypobaric Cold Storage Technology on Preservation of Fresh-cut Fruits and Vegetables%减压冷藏技术对鲜切果蔬保鲜效果的研究

    Institute of Scientific and Technical Information of China (English)

    胡欣; 张长峰; 郑先章

    2012-01-01

    以花王菜等6种蔬菜和苹果为试材,研究减压冷藏技术对鲜切果蔬的保鲜效果.结果表明,减压冷藏处理技术是可应用于鲜切果蔬保鲜的新技术.将果蔬原材料经减压冷藏处理(压力范围为600~3 200 Pa),再清洗切割加工成鲜切产品,可比普通冷藏有效减缓山药、土豆和苹果等鲜切产品的褐变;明显减少鲜切花王菜、鸡毛菜和空心菜的萎蔫、黄叶与腐烂,保持鲜切绿叶菜的新鲜品质;切割前的减压冷藏结合真空预冷,可大大减轻鲜切西兰花的黄化、萎蔫、花粒变大、脱落及切面的褐变与腐烂,显著延长鲜切果蔬的冷藏货架期及冷链断链保鲜期.%The experiments used 6 kinds of vegetables and apple as material to research the preservation effects by using hypobaric cold storage technology. The results indicated that, the hypobaric cold storage treatment technology was an advanced new technology of preservation and process for fresh-cut vegetables and fruits. The raw materials of fruits and vegetables were treated by hypobaric cold storage, pressure 600-3 200 Pa, followed washing and cutting to fresh-cut products. Compared with normal cold storage, the hypobaric cold storage treatment technology could retard the brown degree of cut face of yam, potato and apple, decrease the wilting, yellow leaf and rotting of Huawang vegetable, Jimao vegetable and swamp cabbage, also kept their good fresh quality. Hypobaric cold storage before cutting combined with vaccum pre -cooling treatment could greatly readuce the yellow changed, wilting, flower grain growing and dropping, brown degree of cut face and rotting of broccoli, and prolong the shelf life of fresh-cut fruits and vegetables and preservation period of cold chain scission.

  12. Establishment of growth model of Listeria monocytogenes in Fresh-cut iceberg lettuce%鲜切结球莴苣中单增李斯特菌生长预测模型的建立

    Institute of Scientific and Technical Information of China (English)

    张引成; 尹晓婷; 雷云; 韦莹莹; 潘磊庆; 屠康

    2013-01-01

    为建立不同温度下鲜切结球莴苣中单增李斯特菌生长模型,将单增李斯特菌接种到鲜切结球莴苣表面,并于不同温度下贮藏,获得其在4、8、16、24和32℃下的生长数据,选用Gompertz模型进行拟合,建立初级生长模型.在此基础上建立二级模型研究温度对初级模型中单增李斯特菌生长动力学参数的影响,并进行数学检验.结果表明,对最大比生长速率和延滞时间建立平方根模型,结果呈良好的线性关系,相关系数R2分别为0.977 2和0.984 7,所建立的预测模型能很好地描述不同温度下单增李斯特菌的生长动态.%This paper was designed to establish the growth model of Listeria monocytogenes in fresh-cut iceberg lettuce in different temperatures.The L.Monocytogenes was inoculated to the surface of fresh-cut iceberg lettuce and then preserved in temperature of 4 ℃,8 ℃,16 ℃,24℃,32 ℃.Gompertz model was selected as the primary model.A secondary model was created to study the effects of temperature on growth kinetics parameters of Listeria monocytogenes in the primary model.Mathematical evaluation was also conducted.The results showed that the regression of Belehradek model well described the effect of temperatures on the maximumgrowth rate and the lag phase,and correlation coefficients of determination were 0.9772,0.9847,respectively.Therefore,the model can predict the growth of L.monocytogenes in fresh-cut iceberg lettuce perfectly.

  13. Effects of Different Packaging Materials on Fresh-keeping of Fresh-cut Potatoes%不同包装材料对鲜切马铃薯的保鲜效果

    Institute of Scientific and Technical Information of China (English)

    覃海元; 杨昌鹏; 潘嫣丽; 黄卫萍; 陈智理

    2009-01-01

    [目的] 研究不同包装材料对鲜切马铃薯的保鲜效果.[方法] 马铃薯经挑选、去皮后切成1.5~2.0 cm厚的切片,用浓度1%的柠檬酸溶液浸泡护色3 min后,放入塑料托盘中,分别用PE、PVDC和PP/PE保鲜膜或复合袋包装,放入5 ℃的冰柜里冷藏8 d,当天及其后每2 d检测1次样品.[结果] 透气性差的PP/PE包装较其他材料更有利于延缓鲜切马铃薯中还原型抗坏血酸的减少,抑制褐变,同时延缓组织内丙二醛(MDA)的积累和电解质渗出率的增加,从而延缓其衰老.[结论] 不同包装材料对鲜切马铃薯的保鲜效果有影响.%[Objective]The research aimed to study the fresh-keeping effects of different kinds of packaging materials on fresh-cut potatoes. [Method]Potato were chosen, peeled and cut into pieces (1.5-2.0 cm). After being dipped in 1.0 % citric acid solution for 3 min, the potato pieces were placed in plastic trays, covered with PE, PVDC and PE/PP film respectively, and then stored at 5 ℃ for 8 days. The fresh-cut potatoes were measured at 0, 2, 4, 6 and 8 day respectively. [Result]The results showed that PE/PP packaging with low gas-permeability could retain ascorbic acid, inhibit browning, slow down the accumulation of malondialdehyde (MDA) and electrolyte leakage, so as to slow down senescing. [Conclusion]Different kinds of packaging materials had different fresh-keeping effects on fresh-cut potatoes.

  14. 真空处理对鲜切莲藕褐变控制的效果%Effect of vacuum processing on browning control of fresh-cut lotus tubes

    Institute of Scientific and Technical Information of China (English)

    张心怡; 曹娜; 杜传来; 姜丽; 郁志芳

    2015-01-01

    Objective To investigate the effect of vacuum processing on browning control of fresh-cut lotus root. Methods The physiological and biochemical indexes includingL*value, respiration intensity, the content of Vc and malondialdehyde, and browning degree of fresh cut lotus roots under normal pressure and vacuum condition both at 4℃ were detected.Results Compared with the atmospheric pressure, vacuum processing could significantly slow down the decreasing rate ofL * value and Vc, and the increasing rate of browning degree, inhibit the respiratory intensity, and reduce the methane dicarboxylic aldehyde (MDA) content as well as the activities of polyphenol oxidase (PPO) and peroxidase (POD) at early stage of storage. Conclusion Vacuum processing can significantly inhibit the browning of fresh cut lotus root during storage.%目的:探讨真空条件对控制鲜切莲藕褐变的影响。方法通过测定4℃常压和真空两种条件下鲜切莲藕 L*值、呼吸强度、Vc 和丙二醛含量及褐变度等生理生化指标,研究真空条件对鲜切莲藕品质的影响。结果与相同温度下的常压贮藏相比,真空显著有利于鲜切莲藕感官品质保持,减慢 L*值的下降和 Vc 的损失,抑制呼吸强度、丙二醛和褐变度的上升,并能有效抑制多酚氧化酶(PPO)和过氧化物酶(POD)的活性。结论真空处理能够显著抑制鲜切莲藕贮藏期间的褐变进程。

  15. 中低温蒸汽处理对鲜切胡萝卜片减菌效果及其品质的影响%Effect of steam sterilization treatments on the quality of fresh-cut carrot slices

    Institute of Scientific and Technical Information of China (English)

    周明晖; 刘书来; 丁玉庭

    2012-01-01

    To explore the effects of steam sterilization treatments on the quality of vegetables,fresh-cut carrot slices were treated by steam with different temperature(50~100℃).The results showed that,with the increase of temperature and time of steam,the amount of microorganisms,moisture,carotenoids,firmness and color of the fresh-cut carrot slices decreased significantly(P0.05).When the low temperature steam(50~70℃) was used for 600s,the amount of microorganisms decreased more than 3lg(cfu/g),with moisture loss below 5% and carotenoids retention above 85%.In addition,it had little effects on the firmness and color of samples.While the moderate temperature steam(80~100℃) and the traditional boiling water blanching had more harmful effects on the carrot slices'quality.It can be concluded that low temperature steam treatments can reduce the amount of microorganisms of fresh-cut carrot slices and keep their quality as much as possible.%以鲜切胡萝卜片为研究对象,采用中低温蒸汽(50~100℃)进行减菌处理,分析了蒸汽处理过程中鲜切胡萝卜片品质指标的变化。结果表明,鲜切胡萝卜片的菌落总数、水分、类胡萝卜素、硬度、色泽等指标均随处理温度及时间的增加而显著减少(P〈0.05)。采用低温蒸汽(50~70℃)处理600s,对胡萝卜片的减菌效果明显,且失水率小于5%,类胡萝卜素保留高于85%,对蔬菜的硬度和色泽影响较小。而经中温蒸汽(80~100℃)及传统的沸水热烫处理后的胡萝卜片,其品质质地明显降低。因此,低温蒸汽减菌处理能有效降低胡萝卜片中的菌落总数,并可最大程度保护其品质质地。

  16. Effects of Chitosan Coating on Factors Relating to Enzymatic Browning of Fresh-Cut Lotus Root Slices%壳聚糖对鲜切莲藕酶促褐变相关因子的影响

    Institute of Scientific and Technical Information of China (English)

    汪伟; 张伟; 孙莹; 高成; 朱丽琴

    2014-01-01

    The effects of chitosan coating of fresh-cut lotus root slices on the quality and relating factors in enzymatic browning were studied to explore the mechanism of chitosan in inhibition of enzymatic browning of fresh-cut lotus roots.Fresh-cut lotus root slices were coated with chitosan in different concentrations ( 1%, 2%) and then stored at 4℃.The results showed that chitosan treatment significantly inhibited the increase of browning degree and weight loss rate, and maintained higher vitamin C and total phenolic content.Chitosan coating significantly inhibited the production of superoxide free radicals ( O2 · -) and H2 O2 content,maintained high catalase activity,and significantly inhibited the activity of polyphenol oxidase and peroixdase during stor-age.Treatment with 2%chitosan showed better effect.%为探讨壳聚糖对鲜切莲藕的酶促褐变抑制机理,在4℃下对鲜切莲藕进行壳聚糖涂膜保鲜试验,研究了不同质量分数(1%、2%)壳聚糖对鲜切莲藕品质的影响和酶促褐变相关因子的影响。结果表明:壳聚糖处理显著抑制了鲜切莲藕贮藏过程中的褐变和水分损失,保持较高的维生素C和总酚含量,显著抑制了超氧阴离子(O2·-)和过氧化氢(H2O2)的积累,保持较高的过氧化氢酶(CAT)活性,并显著抑制了多酚氧化酶(PPO)和过氧化物酶(POD)活性。且2%的壳聚糖处理效果更好。

  17. PENGARUH CaCl2 DAN EDIBLE FILM TERHADAP PENGHAMBATAN CHILLING INJURY BUAH NANGKA KUPAS [Effect of CaCl2 and Edible Film on Chilling Injury Inhibition of fresh-cut Jackfruits

    Directory of Open Access Journals (Sweden)

    Ida Bagus Banyuro Partha1

    2009-06-01

    Full Text Available Effect of CaCl2 soaking and edible film coating to delay or inhibit chilling injury of freshly-cut jackfruit has been studied. The onset of chilling injury was monitored based on sadden increase of ethylene emission as measured on-line using CO2-laser driven photoacoustic spectrometer. Freshly cut edible part of ripe jackfruit was used as the research material. The fruit was soaked in 0%, 1%, 1,5%, 2% of CaCl2 for 15 minutes. After rinsing, sample were divided into two parts each for edible coating and control. The edible film was prepared by soaking of the samples for 30 seconds in solution of white bean (Phaseolus lunatus, L. edible coating, which was derived from our previous research. The samples were devided into two parts for destructive and non destructive analysis. Both were then stored at 4oC for 3 days, at which time the normal fruit suffer from chilling injury. For the non-destructive analysis, the samples were individually put in special cuvet and a flow-trough air system was connected to each cuvet for on-line ethylene monitoring. Data of real-time ethylene emission were collected automatically every 120 minutes during the three day cold storage. The other set of samples were put in a plascic bag and stored at 4oC for 3 days period. At the end of cold stored, the samples were let to adjust to room temperature for 1 hr before subjected to respiration rate, reducing sugars, total acidity, and texture analysis. Result indicated that soaking with CaCl2 and edible film coating of freshly-cut jackfruit delayed the on-set of chilling injury as indicated by late increase of ethylene emission. Based on pattern of ethylene emission during the three day storage and their respiration rate, the best treatment to delay chilling injury of fresly-cut jackfruit was soaking in CaCl2 2% in combination with edible film coating.

  18. Efeito do cloreto de cálcio na qualidade de abacaxi 'Pérola' minimamente processado Effect of calcium chloride on quality of fresh-cut 'Pérola' pineapple

    Directory of Open Access Journals (Sweden)

    Lucimara Rogéria Antoniolli

    2003-09-01

    Full Text Available O objetivo deste trabalho foi avaliar os efeitos do cloreto de cálcio na qualidade do abacaxi 'Pérola' minimamente processado. Os tratamentos, arranjados em delineamento inteiramente casualizado e dispostos em esquema fatorial 3x5, consistiram das concentrações de CaCl2 e dos períodos de armazenamento, com três repetições. Frutos previamente sanitizados foram descascados mecanicamente, fatiados manualmente e imersos em solução de CaCl2 a 1% e a 2% e em água (controle, durante 30 segundos. As fatias foram acondicionadas em embalagens de polietileno tereftalato e mantidas à temperatura de 4±1°C durante períodos de 0, 3, 6, 9 e 12 dias. A textura não foi influenciada por nenhum dos fatores estudados. Constatou-se menor atividade peroxidásica nos frutos tratados com CaCl2 2%. Quanto à coloração, a imersão em solução de CaCl2 1% resultou em fatias mais escurecidas, com menor valor L* e maior valor a* ao final do período de armazenamento. A utilização de CaCl2 em abacaxi 'Pérola' minimamente processado não proporciona efeitos benéficos na textura, e interfere negativamente na coloração da polpa do fruto.The objective of this research was to evaluate the effects of calcium chloride on quality of fresh-cut 'Pérola' pineapple. The experimental design was a completely randomized in a 3x5 factorial scheme, and the treatments were represented by the CaCl2 concentration and storage time, each one with three replicates. Fruits were sanitized, peeled mechanically, sliced manually and dipped into water (control and in CaCl2 solutions (1% and 2% for 30 seconds. Slices were placed in polyethylene terephtalate packages and stored at 4±1°C during periods of 0, 3, 6, 9 and 12 days. Texture was not influenced by any of the studied factors. Smaller peroxidase activity in the samples submitted to CaCl2 2% was verified. Fresh-cut pineapple slices dipped in CaCl2 1% showed more browning, presenting smaller L* value and larger a* value at

  19. Research on preservation effects of ozone treatment combined with modified atmosphere packaging of fresh-cut vegetable%臭氧协同气调包装对鲜切叶菜的保鲜作用研究

    Institute of Scientific and Technical Information of China (English)

    华璐云; 雷桥; 谢晶

    2012-01-01

    采用臭氧水处理鲜切大白菜,并进行气调包装贮藏,通过正交实验法分析相关生理指标与保鲜效果,主要研究了4℃贮藏期间菌落总数、失重率、细胞膜透性、多酚氧化酶活性、VC含量和感官品质的变化。实验结果显示:臭氧水处理结合气调包装能有效控制微生物数量,保护了细胞膜透性及降低了VC含量的损失,并对多酚氧化酶有抑制作用,感官品质优良,可使鲜切白菜在4℃条件下保藏至20d以上。极差分析表明:优化的工艺参数为1.44mg/L的臭氧水处理5min协同5%O2/20%CO2/75%N2的气调包装。%Physiological indexes and preservation effects of fresh cut cabbage treated with ozone water combined with modified atmosphere packaging were studied.Analysis included total bacteria counts,weight loss rate,membrane permeability,PPO activity,VC content and sensory qualities during storage at 4℃.Results indicated that ozone treatment combined with modified atmosphere packaging was effective in controlling the total bacteria counts and protecting membrane permeability,and decreasing the loss of VC content and PPO activity.The shelf-life of fresh-cut cabbage was more than 20 days at 4℃ with better sensory qualities.The optimized preservation conditions by range analysis were as follows:treating fresh-cut cabbage with 1.44mg/L ozone for 5min and packing with 5% O2/20% CO2/75% N2.

  20. Effect of chitosan edible coating incorporated with origanum essential oil on preservation of fresh-cut pineapple%壳聚糖涂膜与牛至精油复配对鲜切菠萝的保鲜作用

    Institute of Scientific and Technical Information of China (English)

    冯可; 胡文忠; 姜爱丽; 萨仁高娃; 徐永平

    2015-01-01

    Objective To study the influence of chitosan edible coating and incorporated with oregano essential oil on preservation of fresh-cut pineapple.Methods The values of the firmness, Vc content, peroxidase (POD), polyphenol oxidase (PPO), catalase (CAT) and lipoxygenase (LOX) activity of fresh-cut pineapple were analyzed by processed with chitosan edible coating incorporated with 0.1%, 0.3% and 0.5% of oregano essential, respectively, with water and chitosan edible coating processing as control.Results The processing of chitosan coating with 0.5% oregano essential oil could slow down softening of the tissue; the processing with 0.1% of oregano essential oil could maintain the decline of Vc content slowly; the POD and CAT activity of fresh cut pineapple were declined when it was processed with chitosan coating containing 0.3% and 0.5% oregano essential oil, and appeared increasing trend under other processing condition. The PPO and LOX activity with chitosan edible coating processing were lower than those of the control. Conclusions Chitosan edible coating incorporation with oregano essential oil would extend shelf-life of fresh-cut pineapple at the condition of keeping nutrition ingredient.%目的:研究壳聚糖涂膜及与牛至精油复配对鲜切菠萝的保鲜的影响。方法在低温环境中,按照0.1%、0.3%和0.5%不同浓度的牛至精油与壳聚糖复配,并分别以水、壳聚糖涂膜处理为对照,分析不同处理方式对鲜切菠萝硬度、Vc 含量、过氧化物酶(POD)、多酚氧化酶(PPO)、过氧化氢酶(CAT)和脂氧合酶(LOX)活性的影响。结果壳聚糖涂膜与0.5%的牛至精油复配后可减缓组织软化;与0.1%牛至精油复配可以维持Vc含量的缓慢降低。在不同处理组中,当含有0.3%和0.5%牛至精油时,鲜切菠萝的POD和CAT活性则呈下降趋势,而其他处理组则显著升高;当含有壳聚糖处理组时,其 PPO和LOX活性则低于对照组。结论壳聚糖与牛至

  1. Avaliação da qualidade do abacaxi "Pérola" minimamente processado armazenado sob atmosfera modificada Evaluation of quality in fresh-cut 'Pérola' pineapple stored under modified atmosphere

    Directory of Open Access Journals (Sweden)

    Juliana Costa Bueno Santos

    2005-04-01

    Full Text Available Objetivou-se com este trabalho verificar o efeito da atmosfera modificada ativa sobre a qualidade do abacaxi minimamente processado. Assim, foram avaliadas as modificações físico-químicas, sensorial e microbiológica do abacaxi 'Pérola' minimamente processado submetido a diferentes atmosferas modificadas passiva e ativamente (controle - atmosfera modificada passiva; 5%O2 + 5%CO2 , 2%O2 + 10%CO2. A atmosfera com 2% O2 + 10% CO2 determinou menor perda de líquido drenado, embora tal perda tenha sido desprezível. A atmosfera modificada ativa preveniu o amaciamento do abacaxi minimamente processado, reduzindo a atividade da poligalacturonase e solubilização péctica. As variáveis pH e vitamina C não foram significativamente afetadas pela atmosfera modificada ativa. Maiores valores de sólidos solúveis totais (SST foram encontrados nos frutos sob atmosfera 5% O2 + 5% CO2 e no caso dos açúcares solúveis o tratamento com 2% O2 + 10% CO2 resultou em maiores teores. De acordo com análise sensorial, os frutos sob atmosfera modificada passiva se sobressaíram com relação ao sabor, aparência e cor. A análise microbiológica detectou valores insignificantes para fungos filamentosos, leveduras e coliformes a 35° e 45°C em todos os tratamentos. Conclui-se que o abacaxi 'Pérola' minimamente processado pode ser armazenado por 8 dias, a 5°C, sob atmosfera modificada passiva.The goal of this work was to verify the effect of active modified atmosphere on the quality of fresh-cut pineapple. Physical-chemical, sensory and microbiological changes of fresh-cut 'Pérola' pineapple treated with passive (control and active (5%O2 + 5%CO2; 2%O2 + 10%CO2 modified atmosphere were studied. The 2%O2 + 10%CO2 combination promoted the lowest loss of drained liquid, although they were negligible. Active modified atmosphere prevented the softening of fresh cut pineapples, reducing the poligalacturonase activity and pectin solubilization. The pH and ascorbic

  2. Anti-browning effect of disodium stannous citrate on fresh-cut lotus%柠檬酸亚锡二钠对鲜切莲藕护色作用的研究

    Institute of Scientific and Technical Information of China (English)

    金定樑; 夏文水

    2011-01-01

    柠檬酸亚锡二钠(DSC)是一种新型护色剂.将DSC用于鲜切莲藕预处理阶段,抑制莲藕多酚氧化酶活力及褐变,探讨影响DSC对鲜切莲藕片护色作用的因素,并与其他常用护色剂的护色效果进行对比.结果表明:DSC对鲜切藕产品低温保藏期间的褐变和多酚氧化酶活力都有很好的抑制作用,在pH 3~6条件下用0.05%~0.2% DSC浸泡液处理15 min后,鲜切藕产品可保持较低的褐变度和多酚氧化酶活力,同时在4℃、20 d内DSC的护色效果稳定;与其他常用护色剂比较,在0.1%的等量护色剂浓度下,DSC护色效果优于柠檬酸、抗坏血酸、异抗坏血畦钠,与亚硫酸氢钠效果相当.%Disodium stannous citrate(DSC)is an effective sntibrowning agent. This investigation was conducted to determine the efficacy of DSC as a browning control agent for use on fresh-cut lotus. Fresh-cut lotus products are prone to browning during the low-temperature preservation, The relative effectiveness of these antibrowning agents for inhibition of enzymatic browning in fresh-cut lotus was determined in terms of colour and enzyme activity measurements with respect to time for approximately 20 days storage period at 4 ℃. The fresh-cut lotus were dipped in treatment solutions for some time, then drained grid placed ;n containers. The resuhs showed that, DSC has good controlling browning effects on the lotus products. Including the enzymatic browning and non-enzymatic browning) The best concentration of DSC is 0. 05 % ~ 0. 2%, the processing lime for 15 min. pH range of applications from 3 to 6. And the effect of DSC in different temperatures on the color-preservation effect includes but not limited, and has the function of stability for the products during the shelf life. Compared with other ancibrowning agents commonly.The effect of 0.1%DSC has the more obvious effects, quite close to the effect of sodium bisulfite. The research has a theoretic guidance for

  3. Active packaging for fresh-cut broccoli using 1-methylcyclopropene in biodegradable sachet/ Embalagem ativa para brócolis minimamente processado utilizando 1-metilciclopropeno em sachê biodegradável

    Directory of Open Access Journals (Sweden)

    Marta de Toledo Benassi

    2006-07-01

    Full Text Available Fresh-cut broccoli florets were packed in polypropylene pots containing a sachet with 1- methylcyclopropene (1-MCP and sealed with biodegradable starch-based film. Broccoli was stored for 8 days at 12oC and after this time the color and the texture of the product were similar of the fresh broccoli, with no off-flavor development or decay. Active packaging with 1-MCP in a sachet was efficient to extent shelf life of broccoli florets retarding yellowing and vitamin C losses. It is an alternative of 1-MCP treatment for fresh-cut products and besides, the sachet can absorbs condensed water reducing spoilage and off-odor development.Brócolis minimamente processados foram embalados em bandejas de polipropileno com sachê contendo 1-metilciclopropeno (1-MCP e selado com filme biodegradável de amido. Os brócolis foram armazenados por 8 dias a 12oC e após este tempo a cor e a textura mantiveram-se similares às do produto fresco, sem desenvolvimento de odor não característico ou podridão. A embalagem ativa contendo 1-MCP na forma de sachê foi eficiente no aumento da vida de prateleira de brócolis, retardando o amarelecimento e a perda de vitamina C. Esta é uma alternativa para o tratamento com 1-MCP para produtos minimamente processados e além disso, o sachê pode absorver a água condensada, reduzindo a deterioração e o desenvolvimento de odor não característico.

  4. Antibacterial effect of 405±5nm light emitting diode illumination against Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella on the surface of fresh-cut mango and its influence on fruit quality.

    Science.gov (United States)

    Kim, Min-Jeong; Tang, Chee Hwa; Bang, Woo Suk; Yuk, Hyun-Gyun

    2017-03-06

    To investigate a potential of 405±5nm light emitting diode (LED) as a novel technology for food preservation, the antibacterial effect of 405±5nm LED on Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella spp. on the surface of fresh-cut mango and its influence on fruit quality were evaluated at different storage temperatures. LED-illumination inactivated 1.0-1.6 logCFU/cm(2) of populations at 4 and 10°C for 36-48h (total dose, 2.6-3.5kJ/cm(2)) regardless of bacterial species, while those on non-illuminated mange remained unchanged or slightly increased during storage. At 20°C for 24h (total dose, 1.7kJ/cm(2)), non-illuminated E. coli O157:H7 and Salmonella gradually grew, whereas LED-illumination reduced 1.2 log of Salmonella and inhibited the growth of E. coli O157:H7. Unlike these, non-illuminated L. monocytogenes cells rapidly increased to 7.3 log, while illuminated cells reached 4.6 log, revealing that LED-illumination delayed their growth. There were no significant (P>0.05) differences in color, antioxidant capacity, ascorbic acid, β-carotene, and flavonoid between non-illuminated and illuminated cut mangoes, regardless of storage temperature. These results suggest that 405±5nm LEDs in combination with chilling temperatures could be applied to preserve fresh-cut fruits without deterioration of physicochemical quality of fruits at food establishments, minimizing the risk of foodborne disease. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. 不同清洗方式对鲜切鸡毛菜保鲜效果的影响%Effect of different washing agents on the preservation of fresh-cut Chinese little greens

    Institute of Scientific and Technical Information of China (English)

    林永艳; 谢晶; 朱军伟; 高志立; 王肽

    2012-01-01

    实验采用臭氧水、电解水、次氯酸钠、超声波对鲜切鸡毛菜进行清洗,自来水清洗作为对照。通过测定贮藏期间叶绿素、Vc亚硝酸盐、细菌总数、感官品质等来比较清洗效果。实验结果表明,臭氧水和超声波处理的样品在杀菌、保持营养物质及感官上的效果相对其他处理的样品要好,贮藏至14d仍有商品价值和食用价值,可作为鲜切鸡毛莱加工过程中的处理方式。%Ozone water,brine electrolysis,sodium hypochlorite and ultrasonic were used to clean the fresh-cut Chinese little greens with tap-water as the control. The chlorophyll,Vc content, nitrite,total bacteria,and sensory quality were determined to evaluate the washing effect. The result indicated that ozone water and ultrasonic had better effect on sterilization ,maintaining nutrient substance and sensory quality than others,and Chinese little greens kept them commodity and edible value until the 14th day, Ozone water and ultrasonic could be used as the cleaning method in the processing of fresh-cut Chinese little greens.

  6. Effects of different cleaning steri l ization methods on preservation of fresh-cut Hang cabbage%清洗杀菌方式对鲜切杭白菜保鲜效果的影响

    Institute of Scientific and Technical Information of China (English)

    雷昊; 谢晶; 乔永祥; 张栓栓; 陈莹莹

    2016-01-01

    以杭白菜为对象,对新鲜杭白菜进行鲜切处理后,研究不同清洗杀菌方式(次氯酸钠溶液:有效氯为0.1 g/L;电解水:pH 为2.3;臭氧水:活氧浓度为1.8 mg/L)对鲜切杭白菜保鲜效果的影响。结果表明:臭氧水清洗能更好地保持鲜切杭白菜感官品质,使菌落总数维持在较低的水平,显著地延缓抗坏血酸和叶绿素含量的降低(P<0.05),有效地延长杭白菜货架期长达6d。%Fresh Hang cabbage,through fresh cutting,was selected to study the effects of preservation with different cleaning sterilization methods (sodium hypochlorite solution with active chlo-rine with 0.1 g/L;electrolysis of water with:pH 2.3;ozone water:active oxygen concentration of 1 .8 mg/L).The results showed that:ozone water was preferable to maintain fresh-cut Hang cabbage sen-sory quality,bringing the total number of colonies maintained at a low level,significantly delayed ascorbic acid content (P<0.05 ), chlorophyll content reduction,and effectively extended the shelf life of Hang cabbage for 6 d.

  7. Filmes plásticos e ácido ascórbico na qualidade de araticum minimamente processado Plastic packaging film and ascorbic acid treatment on the quality of fresh cut araticum

    Directory of Open Access Journals (Sweden)

    Manoel Soares Soares Júnior

    2007-12-01

    Full Text Available O objetivo deste trabalho foi avaliar os efeitos do ácido ascórbico e do tipo de filme plástico como embalagem na qualidade do araticum minimamente processado e mantido sob refrigeração. O ácido ascórbico não evitou o escurecimento do araticum minimamente processado. Independentemente do tipo de embalagem, a acidez titulável aumentou com o tempo. A embalagem de policloreto de vinila ou polietileno de baixa densidade promoveu uma significativa perda de massa se comparada com a a laminada a vácuo. A embalagem laminada a vácuo propiciou vida-de-prateleira mais longa ao produto, o qual permaneceu com aparência adequada e qualidade comercial até o sétimo dia do armazenamento. A vida-de-prateleira dos demais tratamentos alcançou somente três dias.This study was aimed at evaluating the effect of ascorbic acid and type of plastic packaging film on the quality of refrigerated fresh cut araticum. Ascorbic acid did not prevent fresh cut araticum from darkening. Regardless of the type of plastic packaging, the fruit titrable acidity increased with time. Packing with polyvynil chloride or with low density polyethylene promoted a significant mass loss compared to laminate vacuum packaging. Laminate vacuum packaging increased the shelf life of the product up 7 days, maintaining its commercial quality and appearance. The shelf life of the other treatments reached 3 days only.

  8. An integrated approach for flavour quality evaluation in muskmelon (Cucumis melo L. reticulatus group) during ripening.

    Science.gov (United States)

    Vallone, Simona; Sivertsen, Hanne; Anthon, Gordon E; Barrett, Diane M; Mitcham, Elizabeth J; Ebeler, Susan E; Zakharov, Florence

    2013-08-15

    Numerous and diverse physiological changes occur during fruit ripening and maturity at harvest is one of the key factors influencing the flavour quality of fruits. The effect of ripening on chemical composition, physical parameters and sensory perception of three muskmelon (Cucumis melo L. reticulatus group) cultivars was evaluated. Significant correlations emerging from this extensive data set are discussed in the context of identifying potential targets for melon sensory quality improvement. A portable ultra-fast gas-chromatograph coupled with a surface acoustic wave sensor (UFGC-SAW) was also used to monitor aroma volatile concentrations during fruit ripening and evaluated for its ability to predict the sensory perception of melon flavour. UFGC-SAW analysis allowed the discrimination of melon maturity stage based on six measured peaks, whose abundance was positively correlated to maturity-specific sensory attributes. Our findings suggest that this technology shows promise for future applications in rapid flavour quality evaluation.

  9. Flavour profiles of three novel acidic varieties of muskmelon (Cucumis melo L.).

    Science.gov (United States)

    Lignou, Stella; Parker, Jane K; Oruna-Concha, Maria Jose; Mottram, Donald S

    2013-08-15

    Novel acidic varieties of muskmelon (Cucumis melo L.) are emerging onto the UK market. These melons contain almost twice the amount of citric acid compared to standard melons and are described as 'zesty and fresh'. This study compared the flavour components of three acidic varieties with a standard Galia-type melon. The volatile and semivolatile compounds were extracted, using dynamic headspace extraction (DHE) or solid-phase microextraction (SPME) and solid phase extraction (SPE), respectively, followed by gas chromatography-mass spectrometry (GC-MS) and gas chromatography-olfactometry (GC-O). More than 50 volatile and 50 semivolatile compounds were identified in the headspace and the SPE extracts, respectively. GC-O revealed 15 odour-active components in the headspace, with esters being consistently higher in the acidic variety. This study showed quantitative and qualitative differences among all four varieties and key differences between acidic varieties and standard melons.

  10. Water Balance Components in Covered and Uncovered Soil Growing Irrigated Muskmelon

    Directory of Open Access Journals (Sweden)

    Paulo Leonel Libardi

    2015-10-01

    Full Text Available ABSTRACT Knowledge of the terms (or processes of the soil water balance equation or simply the components of the soil water balance over the cycle of an agricultural crop is essential for soil and water management. Thus, the aim of this study was to analyze these components in a Cambissolo Háplico (Haplocambids growing muskmelon (Cucumis melo L. under drip irrigation, with covered and uncovered soil, in the municipality of Baraúna, State of Rio Grande do Norte, Brazil (05º 04’ 48” S, 37º 37’ 00” W. Muskmelon, variety AF-646, was cultivated in a flat experimental area (20 × 50 m. The crop was spaced at 2.00 m between rows and 0.35 m between plants, in a total of ten 50-m-long plant rows. At points corresponding to ⅓ and ⅔ of each plant row, four tensiometers (at a distance of 0.1 m from each other were set up at the depths of 0.1, 0.2, 0.3, and 0.4 m, adjacent to the irrigation line (0.1 m from the plant row, between two selected plants. Five random plant rows were mulched using dry leaves of banana (Musa sp. along the drip line, forming a 0.5-m-wide strip, which covered an area of 25 m2 per of plant row with covered soil. In the other five rows, there was no covering. Thus, the experiment consisted of two treatments, with 10 replicates, in four phenological stages: initial (7-22 DAS - days after sowing, growing (22-40 DAS, fruiting (40-58 DAS and maturation (58-70 DAS. Rainfall was measured with a rain gauge and water storage was estimated by the trapezoidal method, based on tensiometer readings and soil water retention curves. For soil water flux densities at 0.3 m, the tensiometers at the depths of 0.2, 0.3, and 0.4 m were considered; the tensiometer at 0.3 m was used to estimate soil water content from the soil water retention curve at this depth, and the other two to calculate the total potential gradient. Flux densities were calculated through use of the Darcy-Buckingham equation, with hydraulic conductivity determined by

  11. Waste cotton as a biodegradable mulching material for transplanted watermelon and cantaloupe production

    Science.gov (United States)

    Low-density polyethylene (LDPE) mulch is commonly used in transplanted vegetable crop production in the southeastern U. S. Cantaloupe and watermelon growers use a system of hybrid transplants, grown on narrow LDPE mulch-covered seedbeds with overhead irrigation, and use the mulch cover for only one...

  12. Modeling the growth of Listeria monocytogenes on cut cantaloupe, honeydew and watermelon.

    Science.gov (United States)

    Danyluk, Michelle D; Friedrich, Loretta M; Schaffner, Donald W

    2014-04-01

    A recent outbreak linked to whole cantaloupes underscores the importance of understanding growth kinetics of Listeria monocytogenes in cut melons at different temperatures. Whole cantaloupe, watermelon, and honeydew purchased from a local supermarket were cut into 10 ± 1 g cubes. A four-strain cocktail of L. monocytogenes from food related outbreaks was used to inoculate fruit, resulting in ~10(3) CFU/10 g. Samples were stored at 4, 10, 15, 20, or 25 °C and L. monocytogenes were enumerated at appropriate time intervals. The square root model was used to describe L. monocytogenes growth rate as a function of temperature. The model was compared to prior models for Salmonella and Escherichia coli O157:H7 growth on cut melon, as well as models for L. monocytogenes on cantaloupe and L. monocytogenes ComBase models. The current model predicts faster growth of L. monocytogenes vs. Salmonella and E. coli O157:H7 at temperatures below 20 °C, and agrees with estimates from ComBase Predictor, and a corrected published model for L. monocytogenes on cut cantaloupe. The model predicts ~4 log CFU increase following 15 days at 5 °C, and ∼1 log CFU increase following 6 days at 4 °C. The model can also be used in subsequent quantitative microbial risk assessments.

  13. Cadmium accumulation by muskmelon under salt stress in contaminated organic soil

    Energy Technology Data Exchange (ETDEWEB)

    Gabrijel, Ondrasek [University of Zagreb, Faculty of Agriculture, Svetosimunska 25, 10000 Zagreb (Croatia)], E-mail: gondrasek@agr.hr; Davor, Romic [University of Zagreb, Faculty of Agriculture, Svetosimunska 25, 10000 Zagreb (Croatia); Zed, Rengel [Soil Science and Plant Nutrition, Faculty of Natural and Agricultural Sciences, University of Western Australia, Crawley WA 6009 (Australia); Marija, Romic; Monika, Zovko [University of Zagreb, Faculty of Agriculture, Svetosimunska 25, 10000 Zagreb (Croatia)

    2009-03-15

    Human-induced salinization and trace element contamination are widespread and increasing rapidly, but their interactions and environmental consequences are poorly understood. Phytoaccumulation, as the crucial entry pathway for biotoxic Cd into the human foodstuffs, correlates positively with rhizosphere salinity. Hypothesising that organic matter decreases the bioavailable Cd{sup 2+} pool and therefore restricts its phytoextraction, we assessed the effects of four salinity levels (0, 20, 40 and 60 mM NaCl) and three Cd levels (0.3, 5.5 and 10.4 mg kg{sup -1}) in peat soil on mineral accumulation/distribution as well as vegetative growth and fruit yield parameters of muskmelon (Cucumis melo L.) in a greenhouse. Salt stress reduced shoot biomass and fruit production, accompanied by increased Na and Cl and decreased K concentration in above-ground tissues. A 25- and 50-day exposure to salinity increased Cd accumulation in leaves up to 87% and 46%, respectively. Accumulation of Cd in the fruits was up to 43 times lower than in leaves and remained unaltered by salinity. Soil contamination by Cd enhanced its accumulation in muskmelon tissues by an order of magnitude compared with non-contaminated control. In the drainage solution, concentrations of Na and Cl slightly exceeded those in the irrigation solution, whereas Cd concentration in drainage solution was lower by 2-3 orders of magnitude than the total amount added. Chemical speciation and distribution modelling (NICA-Donnan) using Visual MINTEQ showed predominance of dissolved organic ligands in Cd chemisorption and complexation in all treatments; however, an increase in salt addition caused a decrease in organic Cd complexes from 99 to 71%, with free Cd{sup 2+} increasing up to 6% and Cd-chlorocomplexes up to 23%. This work highlights the importance of soil organic reactive surfaces in reducing trace element bioavailability and phytoaccumulation. Chloride salinity increased Cd accumulation in leaves but not in fruit

  14. Cadmium accumulation by muskmelon under salt stress in contaminated organic soil.

    Science.gov (United States)

    Ondrasek, Gabrijel; Gabrijel, Ondrasek; Romic, Davor; Davor, Romic; Rengel, Zed; Zed, Rengel; Romic, Marija; Marija, Romic; Zovko, Monika; Monika, Zovko

    2009-03-15

    Human-induced salinization and trace element contamination are widespread and increasing rapidly, but their interactions and environmental consequences are poorly understood. Phytoaccumulation, as the crucial entry pathway for biotoxic Cd into the human foodstuffs, correlates positively with rhizosphere salinity. Hypothesising that organic matter decreases the bioavailable Cd(2+) pool and therefore restricts its phytoextraction, we assessed the effects of four salinity levels (0, 20, 40 and 60 mM NaCl) and three Cd levels (0.3, 5.5 and 10.4 mg kg(-1)) in peat soil on mineral accumulation/distribution as well as vegetative growth and fruit yield parameters of muskmelon (Cucumis melo L.) in a greenhouse. Salt stress reduced shoot biomass and fruit production, accompanied by increased Na and Cl and decreased K concentration in above-ground tissues. A 25- and 50-day exposure to salinity increased Cd accumulation in leaves up to 87% and 46%, respectively. Accumulation of Cd in the fruits was up to 43 times lower than in leaves and remained unaltered by salinity. Soil contamination by Cd enhanced its accumulation in muskmelon tissues by an order of magnitude compared with non-contaminated control. In the drainage solution, concentrations of Na and Cl slightly exceeded those in the irrigation solution, whereas Cd concentration in drainage solution was lower by 2-3 orders of magnitude than the total amount added. Chemical speciation and distribution modelling (NICA-Donnan) using Visual MINTEQ showed predominance of dissolved organic ligands in Cd chemisorption and complexation in all treatments; however, an increase in salt addition caused a decrease in organic Cd complexes from 99 to 71%, with free Cd(2+) increasing up to 6% and Cd-chlorocomplexes up to 23%. This work highlights the importance of soil organic reactive surfaces in reducing trace element bioavailability and phytoaccumulation. Chloride salinity increased Cd accumulation in leaves but not in fruit peel and

  15. Induces Resistance Against Fusarium and Pink Rots by Acibenzolar-S-Methyl in Harvested Muskmelon (cv. Yindi)

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Acibenzolar-S-methyl (ASM) is a chemical activator of systematic resistance in many plants. The effect of preharvest and postharvest application of ASM was evaluated for its ability to induce resistance in muskmelon fruit. The results indicated that 50 and 100 mg L-1 ASM or 1 Ml L-1 imazalil at 1 week or 1 day before harvest were effective in reducing the lesion area with 100 mg L-1 ASM the most effective. No treatment inhibited the infection rate. The postharvest results showed that 50 and 100 mg L-1 ASM, and 0.1 mL L-1 imazalil were effective in reducing the lesion area with 100 mg L-1 ASM the most effective. No treatment inhibited the infection rate. There was a clear time-dependent response of the fruit to postharvest ASM treatment, in which treatments applied 1, 3, and 5 day before inoculation provided the best results.ASM did not demonstrate any fungicide effect in vitro and suppressed lesion area in treated muskmelons, indicating that disease resistance was induced. The protection of ASM was associated with the activation of peroxidase (POD) in treated muskmelons.

  16. Separation and Identification of the Dominant Spoilage Microorganism in Film Packaged Fresh-cut Vegetables%膜包装鲜切蔬菜中主要腐败菌的分离与鉴定

    Institute of Scientific and Technical Information of China (English)

    陈湘宁; 钟思琼; 金文斌; 张继荣; 孟令川; 刘慧

    2012-01-01

    The film packaged fresh-cut vegetables including carrot and purple cabbage and broccoli are the research object in this paper. In order to identify the dominant spoilage microorganism and analyze the influence of different source and storage temperature on the number of dominant spoilage microorganism during storage. Taking the plate counting method to calculate the total number of colonies of bacteria, yeast and mould which lead to spoilage and identify the dominant species by tiny biochemical reaction. The results show that: bacteria is the main pollution microorganism; different samples of carrot make significant difference on the total number of colonies (P0.05). The storage temperature has big influence on the number of microorganism, low temperature can restrain the growth of microorganism. The dominant spoilage microorganism in carrot is Stenortrophomonas maltophilia, its number of colonies take 69%-75% in finished product and 59% in self-made fresh-cut vegetables; the dominant spoilage microorganism in purple cabbage is Pseudomonas corrugate, its' number of colonies take 66%-70% in finished product and 62% in self-made fresh-cut vegetables; the dominant spoilage microorganism in broccoli is Pseudomonas corrugate, its number of colonies take 72%-77% in finished product and 70% in self-made fresh-cut vegetables. The dominant spoilage microorganisms in those fresh-cut vegetables are p9ychrophilic bacteria.%以胡萝卜、紫甘蓝和西兰花膜包装鲜切菜为研究对象,分析3种鲜切莱贮藏期间的主要腐败菌类,探讨不同样品来源和贮藏温度对主要腐败菌数量的影响.采用标准平板活菌计数法,对引起鲜切菜腐败的主要细菌、酵母菌和霉菌的菌落总数进行测定,并利用微量生化反应鉴定技术确定主要腐败菌的种类.研究结果表明,细菌是污染鲜切莱的主要微生物.对于胡萝卜鲜切菜,不同样品来源之间对细菌菌落总数的影响差异显著(P<0.05),

  17. Comparação entre cultivares de carambola para produção de produtos minimamente processados Comparison among cultivars of star fruits for production of fresh-cut

    Directory of Open Access Journals (Sweden)

    Flávia Okushiro Ogassavara

    2009-06-01

    minimamente processados.This work characterized star fruits 'Hart', 'Malasia' and 'Nota 10', to produce fresh-cut. Fruits newly picked were hygienized, stored for l2 hours at 12± 1ºC and 90 ± 5%RH, processed and the product was packaged in PET packages, and stored at 10.3 ± 1ºC and 80 ± 5%RH during 8 days. The fruit yield for fresh-cut production was evaluated, as well as its quality evolution every 2 days, for weight loss, appearance, rotten occurrence, colour, pH, titratable acidity contents (TA, soluble solids (SS, ascorbic acid (AA and ratio SS/TA. Fresh-cut yield was lower for 'Hart' (44.70%, intermediate for 'Nota 10' (66.38% and higher for 'Malasia' (72.58%. The weight loss, during the storage, was significantly greater on 'Hart' products, when compared to other cultivars. The appearance of products produced from 'Malasia' fruit kept good up to 6 days (level 3, when they showed themselves with marks of darkness; while that one produced with 'Harts' and 'Nota 10' kept good appearance for 4 days (level 3. The colour of the products changed from greenish to green-yellowish, as can it be showed for medium hue value, from 115.40 to 110.48. Soluble solids content of fresh-cut from 'Malasia' (7.26ºBrix and 'Hart' (6.97ºBrix did not vary significantly, and it was lower for 'Nota 10', 8.8ºBrix to 7.1ºBrix. Titratable acidity and pH (3.80 - 3.90 did not vary for 'Malasia' and 'Hart' products, leading to an unchangeable ratio. Ascorbic acid content of three cultivars presented an increase followed by a reduction during the storage period. The results indicated that 'Malasia' fruits were the better than Hart and Nota 10 cultivars for fresh-cut production.

  18. 鲜切雷竹笋冷藏过程中木质化机理的研究%Lignification Mechanism of Fresh-Cut Bamboo Shoots during Cold Storage

    Institute of Scientific and Technical Information of China (English)

    周琦; 陈季旺; 高俊; 蔡广霞; 庞彦卿; 宋光森

    2012-01-01

    The activities of phenylalanine ammonialyase (PAL), peroxidase (POD) and polyphenol oxidase (PPO) and the contents of malondialdehyde (MDA), polyphenol and lignin in fresh-cut bamboo shoots stored at 4 ℃ were measured and the lignification mechanism was explored. The results indicated that the activities of PAL and POD and MDA content tended to increase and then decrease with increasing storage time. PPO activity slowly ascended during the first 6 days, and began to descend on the 15 day, whereas polyphenol content sharply declined during the ftrst 6 days, then slow rose, and began to decline again on the 12th day. Lignin content showed a continuous increase, which was 5%-26% in the bottom, 3%-24% in the middle and 2%-22% in the top. These data suggest that the activities of PAL and POD considerably increase during cold storage, which are the key enzymes in the lignification of fresh-cut bamboo shoots. Moreover, phenolic compounds are involved in the synthesis of lignin by providing precursors. Meanwhile, MDA may also be involved in the lignification of fresh-cut bamboo shoots, which needs further identification. Lignin content gradually decreases from the bottom to the top of bamboo shoots, implying the lignification process proceeds from the bottom to the top.%研究鲜切雷竹笋在4℃冷藏条件下苯丙氨酸解氨酶(PAL)、过氧化物酶(POD)和多酚氧化酶(PPO)活力及丙二醛(MDA)、多酚、木质素含量的变化规律,探讨其木质化机理。结果显示:在冷藏过程中,PAL、POD活力、MDA含量呈先上升,后下降的趋势;PPO活力在前6d缓慢上升,第15天开始下降;多酚含量在冷藏前6d急剧下降,后缓慢上升,第12天又开始下降;木质素含量不断增加,基部为5%~26%,中部为3%~24%,尖部为2%~22%。结果表明:在冷藏期内,PAL、POD活力:赶幅度增加,是导致鲜切雷竹笋木质化的关键酶;酚类物质

  19. 茉莉酸甲酯处理抑制鲜切梨褐变机理的研究%Study on the mechanism of browning inhibited by methyl jasmonate treatment on fresh-cut pear

    Institute of Scientific and Technical Information of China (English)

    王艳颖; 胡文忠; 姜波; 金黎明

    2012-01-01

    In order to develop new methods in keeping fruits and vegetables fresheness, effects of different concentrations of methyl jasmonate treatment on enzymatic browning of fresh-cut crystal pear during room temperature storage were investigated.The results showed that the relative conductivity increased rapidly, the content of polyphenol and the activity of polyphenol oxidase (PPO) increased then formed enzymatic browning showed the L* value decreasing gradually in pear after cutting, and the damage from cutting aggravated membrane lipid peroxidation, and induced the activity of peroxidase (POD), superoxide dismutase (SOD), catalase(CAT) to remove excess free radicals for increasing the stress resistance of the fruit. Methyl jasmonate treatment protected the cell membranes, inhibited the leakage of phenolic compounds and PPO activity, weaken the trend of enzymatic browning;and it delayed the rising of POD, SOD, CAT activity in order to maintain longer time the capacity of scavenging free radical thus postponed the membrane lipid peroxidation process.Especially, ltJmol/L methyl jasmonate treatment was more effective in maintaining the storage quality of fresh-cut pears and delaying the aging of fresh-cut pear%为探索鲜切果蔬保鲜的新途径,以鲜切水晶梨为试材,研究了不同浓度的茉莉酸甲酯对常温下贮藏的鲜切梨酶促褐变的影响。结果表明,梨经过鲜切后,相对电导率快速上升,多酚含量和PPO活性增加而发生酶促褐变,L^+值逐渐下降;而且切割伤害加剧了膜脂过氧化,进而诱导了POD、SOD、CAT活性的增加以清除过剩的自由基,提高果实的抗逆性。而茉莉酸甲酯处理保护了细胞膜结构,抑制了酚类物质外泄和PPO活性,减弱了酶促褐变的趋势;同时它也延缓了POD、SOD、CAT活性的上升以维持较长时间清除自由基的能力,从而推迟了膜脂过氧化的进程。尤其是1μmlol/L的茉莉酸甲酯处理更有

  20. Inactivation of Listeria monocytogenes, Salmonella spp. and Escherichia coli O157:H7 on cantaloupes by octenidine dihydrochloride.

    Science.gov (United States)

    Upadhyay, Abhinav; Chen, Chi-Hung; Yin, Hsinbai; Upadhyaya, Indu; Fancher, Samantha; Liu, Yanyan; Nair, Meera Surendran; Jankelunas, Leanne; Patel, Jitendra R; Venkitanarayanan, Kumar

    2016-09-01

    The efficacy of a new generation disinfectant, octenidine dihydrochloride (OH), as wash and coating treatments for reducing Listeria monocytogenes (LM), Salmonella spp. (SAL), and Escherichia coli O157:H7 (EC) on cantaloupe was investigated. Cantaloupe rind plugs inoculated separately with the three bacterial species (∼8 log CFU/cm(2)) were washed for 1, 3, 5 min at 25 °C in water, or chlorine (200 ppm), ethanol (1%), OH (0.01, 0.05, 0.1%) and surviving populations were measured after treatment. Additionally, inoculated cantaloupe rind plugs were coated with 2% chitosan or chitosan containing OH (0.01, 0.05, 0.1%) and sampled for surviving pathogens. Subsequently, the antimicrobial efficacy of OH wash and coating (0.1, 0.2%) on whole cantaloupes was determined. All OH wash reduced LM, SAL, and EC on cantaloupe rinds by > 5 log CFU/cm(2) by 2 min, and reduced populations to undetectable levels (below 2 log CFU/cm(2)) by 5 min (P < 0.05). Similarly, OH coating on cantaloupe rinds reduced the pathogens by 3-5 log /cm(2) (P < 0.05). Washing and coating whole cantaloupes with OH reduced the three pathogens by at least 5 log and 2 log CFU/cm(2), respectively (P < 0.05). Results suggest that OH could be used as antimicrobial wash and coating to reduce LM, SAL, and EC on cantaloupes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Effect of alginate coatings with cinnamon bark oil and soybean oil on quality and microbiological safety of cantaloupe.

    Science.gov (United States)

    Zhang, Yue; Ma, Qiumin; Critzer, Faith; Davidson, P Michael; Zhong, Qixin

    2015-12-23

    The quality and microbiological safety of cantaloupes can potentially be improved using antimicrobial coatings that are able to maintain effectiveness throughout storage. The objective of this work was to study the effect of coating mixtures containing sodium alginate and cinnamon bark oil (CBO) on the quality of cantaloupes and the survival of inoculated bacterial pathogens and naturally occurring yeasts and molds during ambient storage at 21 °C. Cantaloupes were dipped in mixtures containing 1% sodium alginate with or without 2% CBO and 0 or 0.5% soybean oil (SBO). Weight loss and total soluble solids content of the flesh were not significantly different among coating treatments. However, changes in color and firmness of cantaloupes were delayed to different extents after coating, most significantly for the CBO+SBO treatment. Cocktails of Salmonella enterica, Escherichia coli O157:H7, or Listeria monocytogenes inoculated on cantaloupes were reduced to the detection limit (1.3 log CFU/cm(2)) and completely inhibited during the 15-day storage by the CBO+SBO treatment, while L. monocytogenes and S. enterica reached populations of 2.9 log CFU/cm(2) and 2.4 log CFU/cm(2), respectively, on cantaloupes coated with CBO alone. Antimicrobial coatings, especially with SBO, also reduced yeast and mold counts on cantaloupes by 2.6 log CFU/cm(2). SBO improved the retention of CBO during storage suggesting it is related to the enhancement of quality and microbiological safety. Findings demonstrated the potential of the antimicrobial coating system studied to improve microbiological safety and quality of cantaloupes.

  2. 丁香、大黄中草药保鲜剂对康乃馨鲜切花保鲜效果的应用研究%Preservative effect of cloves and rhubarb formula on fresh cut carnation

    Institute of Scientific and Technical Information of China (English)

    童红梅

    2013-01-01

    以康乃馨鲜切花‘黄莺’‘凯旋’为试验材料,选用95%乙醇超声波提取丁香、大黄等10种市售中草药中的抑菌成分,通过对致病菌黑曲霉、灰绿青霉的抑菌试验筛选适宜康乃馨鲜切花‘黄莺’与‘凯旋’保鲜用的中草药配方。结果表明:中草药丁香、大黄的抑菌效果与对照多菌灵相当。以中草药丁香和大黄浸提液、蔗糖、氯化钙、水扬酸4种成分经正交试验筛选出了两种中草药保鲜剂,其中保鲜剂1号对康乃馨‘黄莺’保鲜效果好,而保鲜剂2号更适宜于康乃馨‘凯旋’的保鲜。两种保鲜剂均可延长康乃馨鲜切花寿命6~8 d,保鲜效果显著。%Taking 1 0 kinds of chinese herbal medicine 9 5% ethanol ultrasonic extracts as antibacterial ingredient,the chinese herbal medicine formula to Aspergillusniger and Peniciliumglaucus were screened on fresh cut carnation ‘Hongying’and ‘Kaixuan’.The cloves and rhubarb formula showed the same anti-bacterial effect as carbendazim.The 2 kinds of chinese herbal medicine preservative formula were screened by orthogonal test.No.1 preservative had better effect to ‘Huangying’carnation,while No.2 preservative was suitable to ‘Kaixuan’carnation.Both No.1 preservative and No.2 preservative could prolong life of fresh cut carnation 6 to 8 days and showed a good preservative effect.

  3. 酸性电解水对鲜切马铃薯酶促褐变抑制效果研究%Inhibition effects of enzymatic browning in fresh-cut potatoes by using acidic electrolyzed oxidizing water

    Institute of Scientific and Technical Information of China (English)

    邓清云; 刘海杰; 张芊

    2012-01-01

    This investigation was conducted to determine the effect that acidic electrolyzed oxidizing water (AEOW) inhibit enzymatic browning in fresh-cut potato slices and which factors affected its efficiency. Through the comparison of several treatments on △L% values of fresh-cut potato slices after different storage time, the results showed that compared to no treatment, AEOW could significantly (P〈0.05) inhibit the enzymatic browning of potato slices and its effect was equal to oxalic acid (20 mg/L) and citric acid (20 mg/L). This study also found that processing time, the temperature of AEOW, processing methods (soaking, flushing, oscillating) would influenced the effect of AEOW on enzymatic browning, besides the volume of AEOW. When the processing time was 15 min, AEOW was 40 ℃, and the processing method was oscillating, AEOW had a better inhibition effect on browning. Also the speed of oscillating was higher, the effect was better.%研究了酸性电解水对鲜切马铃薯酶促褐变的抑制效果,并进一步探究了影响酸性电解水抑制酶促褐变效果的外因。通过比较几种方式处理的马铃薯切片在不同贮藏期的褐变度,结果表明,与无处理相比,340e指标的酸性电解水均能够显著(P〈0.05)抑制鲜切马铃薯的酶促褐变,其抑制效果与草酸(20mg/L)、柠檬酸(20mg/L)相当。同时研究发现,处理时间、酸性电解水的温度、处理方式(静止浸泡、流水冲洗、振荡)对酸性电解水的褐变抑制效果均产生影响,而料液比变化对酸性电解水的褐变抑制效果影响不大。处理时间为15min,酸性电解水温度为40℃,振荡处理酸性电解水的褐变抑制效果好,且振荡速度越大,效果越好。

  4. 草酸与柠檬酸抑制鲜切香蕉酶褐变的比较研究%Study on inhibition of enzymatic browning of fresh-cut banana by oxalic acid and citric acid

    Institute of Scientific and Technical Information of China (English)

    覃海元; 杨昌鹏; 陈智理; 黄卫萍; 潘嫣丽

    2011-01-01

    The effectiveness of oxalic acid and citric acid in enzymatic browning inhibition of fresh-cut banana slices were studied.At the first experiment, banana slices were dipped in 0,5,10,20,40,60,80,100mmol/L oxalic acid solution and citric acid solution for 5min, respectively, and then stored at room temperature for 8h.The L * values of banana slices were measured every two hours.At the second experiment, banana slices were dipped in 60mmol/L oxalic acid solution and citric acid solution with or without 0.5% sodium isoascorbate for 5min, respectively,packaged in plastic trays covered with PE film, and then stored at 10℃ for 5ad.The L * values of banana slices were measured every day.The results showed that both oxalic acid and citric acid could inhibit browning of fresh-cut banana effectively, but oxalic acid had better anti- browning effectiveness than citric acid, no matter at room temperature or at low temperature.%对草酸和柠檬酸抑制鲜切香蕉片酶褐变的效果进行了研究.鲜切香蕉片分别用0、5、10、20、40、60、80、100mmol/L的草酸和柠檬酸溶液浸泡5 min,然后置于白纸上常温存放8h,每2h抽样测定香蕉片的L*值;鲜切香蕉片分别用60mmol/L草酸,60mmol/L柠檬酸、60mmol/L草酸+0.5%异杭坏血酸钠和60mmol/L柠檬酸+0.5%异抗坏血酸钠溶液浸泡5min,然后装在塑料托盘里,用PE保鲜膜包扎,在10℃下贮藏5d,每天抽样测定香蕉片的L*值.结果表明,无论常温还是低温下,草酸和柠檬酸均可有效抑制鲜切香蕉褐变,而且草酸抑制鲜切香蕉褐变的效果均好于柠檬酸.

  5. 鲜切茄子酶促褐变的过氧化物酶的特性研究%Study on the Characteristics of Enzyme Browning of Peroxidase in Fresh-cut Eggplant

    Institute of Scientific and Technical Information of China (English)

    刘春丽; 陈欲云

    2012-01-01

    鲜切茄子在切片、贮藏和货架销售过程中易发生酶促褐变,从而降低其品质。文章对鲜切茄子褐变的过氧化物酶的酶学特性进行了深入研究。结果表明:茄子皮的过氧化物酶活性略高于茄子肉,过氧化物酶的最适pH为6左右,在pH6~8范围内较稳定;该酶的最适反应温度为40℃左右,对热稳定性较差,90℃加热4 min,过氧化物酶完全失去活性。考察了抗坏血酸、L-半胱氨酸、亚硫酸氢钠对茄子过氧化物酶的抑制作用,其抑制效果依次是抗坏血酸〉L-半胱氨酸〉亚硫酸氢钠。%Enzyme browning is likely to occur in the process of cut,storage and sell of fresh-cut eggplant,which lower the quality of eggplant.The enzymology properties of peroxidase in the browning of fresh-cut eggplant is lucubrated.The results showed the activity of peroxidase of the skin is slightly higher than the flesh and the optimum pH of peroxidase was 6.Peroxidase is stable when the pH ranges from 6 to 8.the The optimum temperature of peroxidase was 40℃ and it is not stable in the heat.Peroxidase lost its activity completely when it was heated at 90℃ for 4 minutes.This paper studied the inhibiting effect of Vc,citric acid and NaHSO3 on the activity of peroxidase of eggplant,and the result was Vccitric acid NaHSO3.

  6. Avaliação da vanilina como agente antimicrobiano em abacaxi 'Pérola' minimamente processado Evaluation of vanillin as an antimicrobial agent on fresh-cut 'Pérola' pineapple

    Directory of Open Access Journals (Sweden)

    Lucimara Rogéria Antoniolli

    2004-09-01

    Full Text Available Procurou-se avaliar os efeitos da vanilina como agente antimicrobiano, bem como o nível de injúria física como fator de contaminação inicial em abacaxi (Ananas comosus (L. Meer cv. Pérola minimamente processado. Fatias e cubos foram obtidos a partir de frutos sanitizados, descascados e fatiados mecanicamente. Os dois tipos de corte foram imersos, separadamente, em água (controle ou soluções de vanilina 3000 ou 5000mg.L-1, durante 30 segundos. Após período de repouso, para drenagem do excesso de líquido, foram acondicionados em embalagens de polietileno tereftalato e mantidos à temperatura de 4 ± 1°C durante 12 dias. As análises microbiológicas, realizadas em intervalos de 3 dias, envolveram a contagem de microrganismos aeróbios mesófilos e de bolores e leveduras e a determinação de coliformes totais e fecais. A utilização de vanilina mostrou-se ineficiente no controle do crescimento da população de microrganismos aeróbios mesófilos e de bolores e leveduras em abacaxi 'Pérola' minimamente processado. O maior nível de injúrias físicas efetuado nos cubos parece favorecer a contaminação inicial do produto.The purpose of this research was to evaluate the effects of vanillin as an antimicrobial agent, as well as the relationship between the injury degree and initial contamination in fresh-cut pineapple (Ananas comosus (L. Meer cv. Pérola. Slices and cubes were obtained from whole fruits that were mechanically peeled and sliced after sanitization. Both kinds of cutting were dipped in pure water (control or vanillin solutions 3000 or 5000mg.L-1, for 30 seconds. After that, the liquid was drained, slices and cubes were placed in polyethylene terephtalate packages and stored at 4 ± 1°C during 12 days. Microbiological analyses were carried out every 3 days and involved mesophile aerobic counts, molds and yeasts and total and fecal coliforms determination. The use of vanillin was inefficient for the control of mesophile

  7. Effects of Nano-SiOx/Chitosan Complex (NSCC) on the Shelf Life and Quality of Fresh-cut Chinese Water Chestnut%纳米SiOx/壳聚糖复合物对鲜切荸荠品质和生理的影响

    Institute of Scientific and Technical Information of China (English)

    徐庭巧; 罗自生; 解静

    2011-01-01

    为了探讨纳米SiOx/壳聚糖复合物(NSCC)涂膜处理对鲜切荸荠的保鲜效果,研究10℃条件下1%NSCC涂膜处理对鲜切荸荠品质和生理的影响.结果表明:NSCC可以有效延缓荸荠在贮藏过程中失水率的增加和L值的下降,对硬度和可溶性固形物含量则无显著影响,但可抑制PAL、PPO、POD的活性,延缓总酚含量和褐变指数的增加,延长鲜切荸荠的货架期.这表明1% NSCC能有效保持鲜切荸荠的品质,延缓鲜切荸荠的生理变化,显示其在鲜切荸荠保鲜上有潜在的应用价值.%In order to determine the effectiveness of nano-SiOx/chitosan complex (NSCC) coating on fresh cut Chinese water chestnut stored at 10 ℃ for 5 days, and the effect of 1% NSCC coating on quality and physiology of fresh cut Chinese water chestnut were investigated. The results indicated the weight loss and L value of fresh cut Chinese water chestnut treated by 1% NSCC coating was inhibited, while the effect on firmness and total soluble solid content were not significant. It also inhibited the phenylalanine ammonia lyase(PAL), polyphenol oxidase(PPO) and peroxidase (POD) activities, maintained lower level of BI and total phenolic content and prolonged shelf-life. The present findings suggested that NSCC treatment can maintain quality and inhibit physiology of fresh cut Chinese water chestnut, and could be used commercially to preservation in fresh cut Chinese water chestnut during storage.

  8. MODELING MOISTURE DIFFUSIVITY AND ENERGY CONSUMPTION OF CANTALOUPE SEEDS IN FIXED AND FLUIDIZED BED CONDITIONS

    Directory of Open Access Journals (Sweden)

    Reza Amiri Chayjan

    2012-12-01

    Full Text Available   Background.The main goal in cantaloupe seed drying is the reduction of its moisture content to a safe level, allowing storage in a long period of time. Fluidized bed dryer is a drying process with better heat and mass transfer and shorter drying time. This method is a gentle and uniform drying procedure. Fluidized bed is suitable for sensitive and high moisture materials. Drying parameters of moisture diffusivity and energy are vitally important in modelling and optimizing of the seed dryer system. Material and methods. This study investigated thin layer characteristics of cantaloupe seeds under fixed, semi fluidized and fluidized bed drying with initial moisture content about 61.99% (d.b.. A laboratory fluid- ized bed dryer was utilized in this research. Air temperature levels of 45, 55, 65 and 75°C were applied in drying experiments. Effective moisture diffusivity (Deff of cantaloupe seeds was computed by Fick’s second law in diffusion. Activation energy and specific energy consumption of cantaloupe seeds under different drying conditions were calculated. Results.Calculated values of Deff for drying experiments were in the range of 2.23·10-10and 8.61·10-10m2/s. Values of Deff increased as the input air temperature increased. Activation energy values were computed be- tween 39.21 and 37.55 kJ/mol for 45°C to 75°C, respectively. Specific energy consumption for cantaloupe seeds was calculated at the boundary of 1.58·105and 6.18·105kJ/kg. Conclusion.Results indicated that applying the fluidized bed condition is more effective for convective drying of cantaloupe seeds. Increasing air velocity tends to decrease in activation energy. Decreasing in drying air temperature in different bed conditions caused increase in the energy value. The aforesaid drying parameters are necessary to optimize the operational condition of fluidized bed dryer and to perfect design of the system.  

  9. Role of ascorbic acid in the inhibition of polyphenol oxidase and the prevention of browning in different browning-sensitive Lactuca sativa var. capitata (L.) and Eruca sativa (Mill.) stored as fresh-cut produce.

    Science.gov (United States)

    Landi, Marco; Degl'Innocenti, Elena; Guglielminetti, Lorenzo; Guidi, Lucia

    2013-06-01

    Polyphenol oxidase (PPO) and, to a minor extent, peroxidase (POD) represent the key enzymes involved in enzymatic browning, a negative process induced by cutting fresh-cut produce such as lettuce (Lactuca sativa) and rocket salad (Eruca sativa). Although ascorbic acid is frequently utilised as an anti-browning agent, its mechanism in the prevention of the browning phenomenon is not clearly understood. The activity of PPO and POD and their isoforms in lettuce (a high-browning and low-ascorbic acid species) and rocket salad (a low-browning and high-ascorbic species) was characterised. The kinetic parameters of PPO and in vitro ascorbic acid-PPO inhibition were also investigated. In rocket salad, PPO activity was much lower than that in lettuce and cutting induced an increase in PPO activity only in lettuce. Exogenous ascorbic acid (5 mmol L(-1)) reduced PPO activity by about 90% in lettuce. POD did not appear to be closely related to browning in lettuce. PPO is the main enzyme involved in the browning phenomenon; POD appears to play a minor role. The concentration of endogenous ascorbic acid in rocket salad was related to its low-browning sensitivity after cutting. In lettuce, the addition of ascorbic acid directly inhibited PPO activity. The results suggest that the high ascorbic acid content found in rocket salad plays an effective role in reducing PPO activity. © 2012 Society of Chemical Industry.

  10. 葡甘聚糖/蜂蜡复合液膜对鲜切琯溪蜜柚保鲜研究%Study on fresh-cut pomelo fresh-keeping by konjac glucomannan(KGM)-beeswax(BW)composite membrane

    Institute of Scientific and Technical Information of China (English)

    赖明耀; 兰润; 李雪晖; 庞杰

    2014-01-01

    该文研究室温(20℃)条件下葡甘聚糖/蜂蜡(KGM/BW)涂膜、葡甘聚糖(KGM)涂膜及对照组对鲜切琯溪蜜柚贮藏期间主要感观品质和理化性质影响。结果表明:KGM涂膜,尤其是KGM/BW涂膜能降低贮藏期间鲜切柚子的水分损失、抑制呼吸作用、减缓营养物质流失,具有良好的保鲜效果。%The effects of KGM/BW coating,KGM coating and the control group under the room temperature(20 ℃)on the sensory quality and physicochemical property of the fresh-cut honey pomelo(Guanxi)during postharvest storage were studied.The results showed that KGM/BW coating, compared to KGM coating group and the control,could protect the flesh-cut fruit best during storage from water loss and inhibit respiration as well as preserve the nutritious quality of the honey pomelo fruit.

  11. Atividade respiratória e evolução de etileno em alface crespa minimamente processada armazenada sob duas temperaturas Respiratory activity and ethylene evolution of fresh-cut crisphead lettuce stored under two temperatures

    Directory of Open Access Journals (Sweden)

    Leonora Mansur Mattos

    2008-12-01

    Full Text Available O processamento mínimo de hortaliças envolve operações que ocasionam diversas alterações metabólicas no tecido processado, como elevação da atividade respiratória e evolução de etileno. A respiração é um processo complexo pelo qual reações químicas oxidam compostos orgânicos a dióxido de carbono e água para produção de energia. O aumento na evolução de etileno é, também, de extrema importância e pode ser observado em hortaliças submetidas ao processamento mínimo. No presente trabalho, estudaram-se efeitos fisiológicos desencadeados pelo processamento mínimo de alface (Lactuca sativa L., visando conhecer a melhor temperatura de armazenamento bem como o estresse causado pelo processamento mínimo afeta o produto. Verificou-se que, logo após o processamento mínimo, as taxas respiratórias eram estatisticamente diferentes para os materiais processados a 5 e 10 mm e folha inteira, tanto na temperatura de 5 ºC quanto a 10 ºC. Verificou-se que o armazenamento a 5 ºC reduziu de forma mais rápida o metabolismo respiratório quando se comparou com o armazenamento a 10 ºC. O perfil das curvas de atividade respiratória e evolução de etileno da alface processada a 10 mm foi o mesmo para as duas temperaturas estudadas, diferindo apenas nos valores, que foram mais altos, conforme esperado, para a temperatura de 10 ºC. No armazenamento à temperatura de 5 ºC, pôde-se observar a redução da evolução de etileno para o material processado a 10 mm, mas não para o processado a 5 mm, nas duas primeiras horas após o processamento mínimo. A melhor temperatura para o armazenamento da alface minimamente processada foi de 5 ºC e o produto processado como folha inteira apresentou menor taxa respiratória e elevação de etileno.Fresh-cut technology involves many operations that might cause metabolic alterations in the processed tissue such as increase in respiration rate and ethylene evolution. Respiration is a complex

  12. Multistate outbreak of listeriosis associated with Jensen Farms cantaloupe--United States, August-September 2011.

    Science.gov (United States)

    2011-10-07

    Listeriosis is caused by Listeria monocytogenes, a gram-positive bacillus common in the environment and acquired by humans primarily through consumption of contaminated food. Infection causes a spectrum of illness, ranging from febrile gastroenteritis to invasive disease, including sepsis and meningoencephalitis. Invasive listeriosis occurs predominantly in older adults and persons with impaired immune systems. Listeriosis in pregnant women is typically a mild "flu-like" illness, but can result in fetal loss, premature labor, or neonatal infection. Listeriosis is treated with antibiotics. On September 2, 2011, the Colorado Department of Public Health and Environment (CDPHE) notified CDC of seven cases of listeriosis reported since August 28. On average, Colorado reports two cases of listeriosis annually in August. By September 6, all seven Colorado patients interviewed with the Listeria Initiative* questionnaire reported eating cantaloupe in the month before illness began, and three reported eating cantaloupe marketed as "Rocky Ford."

  13. PCR detection and microbiological isolation of Salmonella spp. from fresh beef and cantaloupes.

    Science.gov (United States)

    Gallegos-Robles, M A; Morales-Loredo, A; Alvarez-Ojeda, G; Osuna-García, J A; Martínez, I O; Morales-Ramos, L H; Fratamico, P

    2009-01-01

    Species belonging to the genus Salmonella are an important cause of enteric fevers, gastroenteritis, and septicemia, and the pathogens are commonly transmitted through contaminated food. In this study, polymerase chain reaction (PCR) amplification of a 287-bp region of the invA gene was compared to a microbiological technique to determine the presence of Salmonella in retail beef and in cantaloupe rinse samples. Both methods showed the same level of sensitivity, detecting 1 CFU/25 g of meat after enrichment for 24 h at 42 degrees C. The presence of Salmonella was determined in 50 commercial top sirloin beef samples that were not artificially inoculated. Three samples were positive by the microbiological method, and these samples and an additional sample were positive by the PCR. Both methods were also used to test surface rinses of cantaloupes collected from 4 farms in Nayarit, Mexico. Salmonella was detected by the microbiological method in 9 of 20 samples (45%), whereas the pathogen was detected by the PCR in 11 samples (55%). This study demonstrates the utility of the PCR targeting the invA gene to determine the presence of Salmonella spp. in beef and cantaloupe samples.

  14. Aroma compounds in fresh cut pomegranate arils.

    Science.gov (United States)

    Little published information exists regarding flavor and aroma compounds in pomegranate (Punica granatum). Although arils have fruity and sweet characteristics, we found no publications describing actual compounds responsible for their typical flavor. Since most commercial usage of pomegranates in...

  15. Postharvest ASM or Harpin Treatment Induce Resistance of Muskmelons Against Trichothecium roseum

    Institute of Scientific and Technical Information of China (English)

    WANG Yi; LI Xuan; BI Yang; GE Yong-hong; LI Yong-cai; XIE Fang

    2008-01-01

    Induced resistance was studied in muskmelons(cv.Yindi)inoculated Trichothecium roseum with postharvest 1,2,3-benzothiadiazole-7-carbothioic acid S-methyl ester(ASM)(100 mg L-1)or harpin(50 mg L-1)treatment.Both ASM and harpin significantly reduced lesion diameter in inoculated fruit.Lesion diameter was limited in the treated and untreated halves of the same fruit,indicating that the local and systemic resistance was induced.Inhibiting efficacy of elicitors lasted 7 and 5 days in the treated and untreated halves.The resistance increased by the chemicals was associated with the activation of peroxidase(POD)and chitinase(CHT).The elicitors induced a significantly and progressively increasing activity of POD and CHT in the treated and untreated halves,and the activation lasted at least 5 days.The activities of POD isoenzymes increased in the treated fruit.However,no new enzyme band was found in the treated and untreated halves.

  16. Incorporation of plant materials in the control of root pathogens in muskmelon

    Directory of Open Access Journals (Sweden)

    Andréa Mirne de Macêdo Dantas

    2013-12-01

    Full Text Available The effect of plant materials[Sunn Hemp (Crotalaria juncea, Castor Bean (Ricinus communis L., Cassava (Manihot esculenta Crantz and Neem (Azadirachta indica] and the times of incorporation of these materials in regards to the incidence of root rot in melon was evaluated in Ceará state, Brazil. The experiment was conducted in a commercial area with a history of root pathogens in cucurbitaceae. The randomized block design was used, in a 5 x 3 factorial arrangement with four repetitions. The treatments consisted of a combination of four plant materials (sunn hemp, castor beans, cassava and neem and a control with no soil incorporation of plant material and three times of incorporation (28, 21, and 14 days before the transplanting of the seedlings. Lower incidence of root rot was observed in practically all of the treatments where materials were incorporated at different times, with variation between the materials, corresponding with the time of incorporation, in relation to the soil without plant material. The pathogens isolated from the symptomatic muskmelon plants were Fusarium solani, Macrophomina phaseolina, Monosporascus cannonballus and Rhizoctonia solani, F. solani being encountered most frequently.

  17. 鲜切蔬菜加工过程追溯的原料批次混合优化模型构建%Establishment of materials batch mixing optimization model for traceability of fresh-cuts fruits and vegetables processing

    Institute of Scientific and Technical Information of China (English)

    邢斌; 刘学馨; 钱建平; 王健; 吴晓明

    2015-01-01

    为了保障鲜切蔬菜加工企业的产品质量安全,提高鲜切蔬菜生产加工效率,减少加工过程中因原料批次而导致的召回正本增加等问题,提出了一种鲜切蔬菜加工过程追溯的批次混合优化问题的解决方案。该研究通过分析鲜切蔬菜加工的基本工艺流程,根据中小规模鲜切蔬菜加工企业的实际生产需求,研究适用于单原料仓库、单成品仓库的生产加工过程,构建基于企业生产订单和多原料批次的生产加工模型。在模型构建上,综合考虑了加工过程中单个订单不可拆分,以及原料批次选取时应优先选取最近未用完批次原则等企业生产加工管理的实际因素。在此基础上应用遗传算法对订单的加工次序和原料批次的选取次序进行优化。采用北京某鲜切蔬菜加工企业的实际生产数据对模型进行验证,采用平均召回规模及平均出成率作为鲜切蔬菜加工的目标函数。结果表明,通过算法优化后的目标函数值与初始值相比提高了10.5%,能够有效减少平均召回规模并提高产品加工的综合出成率,该模型为中小规模鲜切蔬菜加工企业的原料批次分配及生产流程的优化提供参考。%In order to protect the quality and safety of products of the fresh cut vegetable processing and improve fresh cut vegetable production and processing efficiency, a fresh cut vegetable processing batch mixing optimization model was put forward, which can reduce the recall cost resulted from the mixed batches during the manufacture. The batch-mixing phenomenon of raw materials often occurs during the production process of fresh-cut vegetables. On the other hand, different batches of materials have different properties which will exert some effects on the rate of the production yield. Proper allocation of the materials’ batches will reduce the recall cost of defective products. In order to enhance the ability of

  18. Características sensoriais e microbiológicas de maçãs minimamente processadas recobertas com películas Sensorial and microbiological characteristics of freshly cut apples with edible coating

    Directory of Open Access Journals (Sweden)

    Luciana Cristina Brigatto Fontes

    2007-03-01

    Full Text Available O objetivo do trabalho foi avaliar as características sensoriais e a microbiologia durante armazenamento refrigerado de maçãs da cultivar Royal Gala minimamente processada (MP, tratadas com solução conservadora e películas comestíveis (dextrina, amido de mandioca e alginato de sódio. Maçãs MP tratadas apenas com a solução conservadora destacaram-se por apresentarem características mais próximas de uma maçã natural recém cortada nos parâmetros de aparência, odor e textura. Nos parâmetros de sabor, este tratamento mostrou-se diferenciado da maçã natural em virtude dos ácidos e sais presentes na solução. As maçãs MP com películas de dextrina e fécula de mandioca apresentaram notas semelhantes nos parâmetros avaliados, evidenciando maior umidade e menor escurecimento que o controle. A película de alginato apresentou-se visivelmente mais espessa e com brilho, o que os provadores associaram como sendo de aparência artificial. Quanto ao tempo de armazenamento, as alterações significativas da maioria dos parâmetros sensoriais avaliados manifestaram-se no 5º dia de armazenamento para as maçãs MP do tratamento controle e, principalmente no 9° dia de armazenamento, para os produtos com película. Foi detectada ausência de Salmonella nas maçãs utilizadas no processamento. Não foram detectados coliformes totais e fecais nas maçãs MP durante todo o período de armazenamento estudado.The aim of this work was to evaluate the sensorial and microbiological characteristics during the refrigerated storage of Royal Gala fresh cut (FC apples treated with conservative solution and edible coating (dextrin, cassava starch and sodium alginate. Freshly cut apples treated with a conservative solution are only really close to the natural ones for presenting characteristics similar in parameters of appearance, odor and texture. In the flavor parameters, this treatment revealed a different flavor to the natural one due to acids and

  19. Efeito do hipoclorito de sódio sobre a microbiota de abacaxi 'Pérola' minimamente processado Effect of sodium hypochlorite on the microflora of fresh-cut 'Pérola' pineapple

    Directory of Open Access Journals (Sweden)

    Lucimara Rogéria Antoniolli

    2005-04-01

    Full Text Available Procurou-se determinar a menor concentração eficiente de hipoclorito de sódio (NaOCl para desinfecção da casca, bem como avaliar a necessidade de utilização do mesmo agente sanitizante no banho de imersão da polpa do abacaxi 'Pérola' minimamente processado. Frutos previamente lavados foram desinfectados com NaOCl 100; 150 ou 200mg.L-1, durante 2 minutos. Após aproximadamente 24 horas de armazenamento refrigerado, os frutos foram descascados e fatiados mecanicamente. As fatias foram imersas em solução de NaOCl 20mg.L-1 ou em água (controle, durante 30 segundos. Após período de repouso, para drenagem do excesso de líquido, foram acondicionadas em embalagens de polietileno tereftalato e mantidas à temperatura de 4 ± 1°C, durante 16 dias. As análises microbiológicas, realizadas em intervalos de três dias, foram: coliformes a 35ºC, coliformes a 45ºC, bactérias aeróbias mesófilas e de bolores, e leveduras. Não foram detectados coliformes totais e fecais em nenhum dos tratamentos, durante 16 dias de armazenamento refrigerado. A desinfecção da casca com NaOCl 200mg.L-1, associada à sanitização da polpa do abacaxi com NaOCl 20mg.L-1, proporcionou menores populações de microrganismos aeróbios mesófilos e de bolores, e leveduras, tornando tais operações imprescindíveis na obtenção de produtos minimamente processados que ofereçam garantia de sanidade ao consumidor.The purpose of this research was to determine the smallest effective concentration of sodium hypochlorite (NaOCl for intact fruit disinfection as well as to evaluate the use of the same disinfectant product for sanitization of the fresh-cut 'Pérola' pineapple. Fruits were washed and disinfected with chlorine solutions (100, 150 or 200mg.L-1 for 2 minutes. After approximately 24 hours of cold storage, fruits were mechanically peeled and sliced. Slices were dipped in 20mg.L-1 of chlorine solution or pure water (control, for 30 seconds. After that, the

  20. Qualidade de tangerina 'poncã' minimamente processada, armazenada a 5°c Quality of fresh-cut 'Poncã' Tangerine, stored at 5°C

    Directory of Open Access Journals (Sweden)

    Daniella Moreira Pinto

    2007-08-01

    Full Text Available Com o presente trabalho, objetivou-se analisar o comportamento da Tangerina 'Poncã' minimamente processada armazenada a 5ºC. O experimento foi executado no Laboratório de Pós-Colheita de Frutas e Hortaliças do Departamento de Ciência dos Alimentos da Universidade Federal de Lavras MG. As frutas foram lavadas com detergente neutro e sanificadas com hipoclorito de sódio a 200 ppm por 15 minutos, descascadas, embaladas e resfriadas imediatamente a 5ºC. Foi utilizado um delineamento inteiramente casualizado simples, com 3 repetições e 3 frutas por parcela experimental. A influência de 5 níveis do fator tempo (0, 3, 6, 9 e 12 dias foi avaliada. A qualidade das frutas foi analisada a partir das seguintes variáveis: perda de massa, rendimento em suco, concentração de O2 e CO2 no interior das embalagens, valores L*, a* e b*, pH, acidez titulável, sólidos solúveis, beta-caroteno e vitamina C. A temperatura de 5°C foi adequada no armazenamento de Tangerina 'Poncã' minimamente processada, baseado nas pequenas modificações na cor, acidez titulável, sólidos solúveis, perda de massa e rendimento do suco, embora, perdas nos teores de vitamina C (34,07% e beta-caroteno (42,75% tenham sido observadas.The objective of the work was to analyze the behavior of the fresh-cut 'Poncã' Tangerine stored 5ºC. The experiment was carried out in the Postharvest Fruit and Vegetables Laboratory of the Food Science Department / Federal University of Lavras - Brazil. The fruit were washed with neutral detergent and sanitized with sodium hipochlorite 200ppm for 15 minutes, peeled, packed and immediately cooled at 5ºC. It was used a fully randomly design, with 3 replications and 3 fruits per plote. The influence of 5 levels of the factor time (0, 3, 6, 9 and 12 days was evaluated. The quality of the fruit was analyzed based in the following variable: mass loss, juiciness, concentration of O2 and CO2 into the packages, L *, a* and b * values, p

  1. Quality evaluation of fresh-cut ‘Pérola’ pineapple stored in controlled atmosphere Avaliação da qualidade do abacaxi ‘Pérola’ minimamente processado, armazenado sob atmosfera controlada

    Directory of Open Access Journals (Sweden)

    Lucimara Rogéria Antoniolli

    2007-09-01

    Full Text Available The purpose of this research was to determine the best gas mixture in controlled atmosphere conditions to store fresh-cut ‘Pérola’ pineapple, particularly in relation to the maintenance of visual quality and reduction of microbial growth. After sanitation, fruit was manually peeled, sliced and dipped in 20 mg.L-1 NaOCl solution for 30 seconds. Then, the excess liquid was drained and the slices were placed in sealed glass jars connected to a flowboard installed in a cold room (5 ± 1 °C. Desired gas mixtures were supplied continuously for 12 days from cylinders connected to the flowboard. Controlled atmospheres of 2:5, 2:10, 2:15, 5:5, 5:10, 5:15, 8:5, 8:10 and 8:15 (O2:CO2, % and air were used. The product was evaluated for pulp color, total and fecal coliforms, mesophilic and psychrotrophic aerobic, mold and yeast counts. Total and fecal coliforms were not detected. The fresh-cut ‘Pérola’ pineapple was not very sensitive to storage in controlled atmosphere, considering that the slices had little browning and were free of contamination, that would affect the food safety at the end of the storage periodProcurou-se determinar a composição gasosa ótima para o armazenamento do abacaxi ‘Pérola’ minimamente processado, particularmente com relação à melhoria da qualidade visual e à redução do crescimento microbiano. Frutos previamente sanitizados foram descascados e fatiados manualmente. As fatias foram imersas em solução de NaOCl 20 mg.L-1 durante 30 segundos. Após período de repouso, para drenagem do excesso de líquido, foram acondicionadas em frascos de vidro herméticos conectados a um fluxcentro instalado em câmara refrigerada a 5 ± 1 °C. As composições gasosas desejadas foram fornecidas continuamente, durante 12 dias, a partir de cilindros conectados ao fluxcentro. As combinações de O2:CO2 (%, balanceadas com N2, foram as seguintes: 2:5, 2:10, 2:15, 5:5, 5:10, 5:15, 8:5, 8:10 e 8:15. O tratamento controle foi

  2. Uso de misturas químicas para a manutenção da firmeza de banana 'Prata' minimamente processada Use of chemical mixtures for firmness maintenance of fresh-cut 'Silver' banana

    Directory of Open Access Journals (Sweden)

    Eduardo Valério de Barros Vilas Boas

    2009-02-01

    Full Text Available A banana constitui interessante alternativa para compor saladas de frutas. No entanto, possui curta vida de prateleira após o processamento mínimo em razão da rápida perda da firmeza. Neste trabalho, objetivou-se avaliar o efeito da mistura química contendo cloreto de cálcio, ácido ascórbico e L-cisteína e/com o uso de atmosfera modificada ativa (10 kPa CO2 e 2 kPa O2, enfatizando a perda de firmeza sobre a qualidade e vida de prateleira de banana 'Prata' minimamente processada. O conteúdo de pectina solúvel e a % de solubilização aumentaram significativamente ao longo do período de conservação. A perda de firmeza e o aumento das atividades das enzimas poligalacturonase e pectinametilesterase apresentaram uma interação significativa entre os fatores estudados (Tratamento/Tempo. As fatias tratadas com misturas químicas permaneceram com boas características para o consumo por até 3 dias de conservação. Os tratamentos com injeção inicial de gases de forma isolada, ou junto ao tratamento com mistura química, não propiciaram maior retenção da firmeza de banana 'Prata' minimamente processada em relação ao tratamento contendo L-cisteína (1% p/v + ácido ascórbico (1% p/v + cloreto de cálcio (1% p/v na mistura química.Banana constitutes an interesting alternative to make fruit salad. Nevertheless, they have short shelf life after cutting due to the fast loss of firmness. The objective of this work was to evaluate the effect of chemical mixtures containing calcium chloride, ascorbic acid and L-cysteine with the use of active modified atmosphere (10 kPa CO2 and 2 kPa O2, emphasizing the lost of firmness on the quality and shelf life of fresh-cut 'Silver' banana. Soluble pectin content and the percentage of solubilization increased significantly throughout the conservation period. The lost of firmness and the increase of pectinmethylesterase and polygalacturonase activities presented a significant interaction among the

  3. Influência de diferentes temperaturas na manutenção da qualidade de Pequi minimamente processado Influence of different temperatures in maintenance of quality of fresh-cut Pequi

    Directory of Open Access Journals (Sweden)

    Clarissa Damiani

    2008-02-01

    Full Text Available Neste trabalho, objetivou-se avaliar o efeito de quatro diferentes temperaturas, 0°C, 5°C, 10°C e 22°C, na qualidade de pequis minimamente processados, durante 15 dias de armazenamento. Os pequis foram lavados, sanificados, seus pirênios extraídos, embalados e armazenados por 15 dias a 0°C e 5°C, 9 dias a 10°C e 3 dias a 22°C. A cada três dias, foram realizadas as análises: taxa respiratória, perda de massa, firmeza, sólidos solúveis, acidez titulável (ácido cítrico, pH, coloração (L* e b* e concentração de O2 e CO2, no interior das embalagens. A taxa respiratória e a perda de massa foram menores quanto menor a temperatura; a firmeza não sofreu variações significativas; os sólidos solúveis sofreram influência somente do tempo, com aumento em seus teores; a acidez titulável aumentou no decorrer do armazenamento, com conseqüente declínio no pH; o valor L* aumentou nos frutos a 0°C e diminuiu naqueles a 22°C; o valor b* decresceu durante o armazenamento e a concentração de gases, no interior das embalagens, teve pouca variação. Pelos resultados, constatou-se que as temperaturas de 0°C e 5°C foram as mais eficazes na manutenção da qualidade de pequis minimamente processados.The objective of the work was to evaluate the effect of four different temperatures, 0°C, 5°C, 10°C and 22°C, on the quality of fresh-cut pequi, during 15 days of storage. The pequi fruit were washed, sanitized, their kernels extracted, packaged and stored for 15 days at 0°C and 5°C, 9 days at 10°C and 3 days at 22°C. The analyses were carried out every three days: respiration rate, mass loss, firmness, soluble solids, titratable acidity (acid citric, pH, coloration (L*and b*value and O2 and CO2 concentrations into the package. The lower temperature the lower respiration rate and mass loss; the firmness did not suffer significant variations; the soluble solids were influenced just by the time, increasing over the storage period

  4. Influência da sanificação sobre a qualidade de melão 'amarelo' minimamente processado: parte II Influence of the sanitation on the quality of the fresh cut yellow melon: part II

    Directory of Open Access Journals (Sweden)

    Helga Parra dos Santos

    2005-10-01

    Full Text Available Visando o melhor aproveitamento, a agregação de valor e a conveniência para o consumo, está sendo empregado o processamento mínimo do melão, colocando no mercado um produto in natura fresco pronto para o consumo. Objetivou-se com esta pesquisa avaliar a qualidade sensorial de melão 'Amarelo' minimamente processado sanificado com peróxido de hidrogênio (H2O2 e dicloro isocianurato de sódio (NaDCC, armazenado a 4 + 1ºC durante 16 dias. Foram realizadas análises de sabor, textura, aparência e cor. Ocorreu redução linear nos valores das notas de sabor e textura ao longo do período de armazenamento. As notas variaram entre 8 (muito boa e 7 (moderadamente boa nos períodos iniciais, reduzindo para 6 (ligeiramente boa e 5 (indiferente ao final do período de armazenamento, não caracterizando a rejeição destes parâmetros por parte dos provadores. O tratamento com H2O2 a 2% teve menor aceitação quanto ao sabor e textura. A aparência e a cor não foram influenciadas pelos tratamentos, mas receberam notas menores ao longo do período de armazenamento. Os valores das notas para aparência e cor se mantiveram em 8 (muito boa até o penúltimo dia, recebendo nota 6 (ligeiramente boa apenas no último dia de armazenamento. De acordo com os resultados obtidos, concluiu-se que o melão 'Amarelo' minimamente processado foi considerado de boa aceitação, não ocorrendo depreciação acentuada na qualidade sensorial. O tratamento com NaDCC 50 ppm obteve melhor aceitação quanto à sabor e textura do que o tratamento com H2O2 a 2%.The goal of this research was to evaluate the sensorial quality of fresh cut 'Yellow' melon, sanitized with hydrogen peroxide (H2O2 and sodium dichloroisocyanurate (NaDCC, stored at 4+ 1ºC for 16 days. Flavor, texture, appearance and color analyses were performed. A linear reduction in the values of the scores of flavor and texture was abserverd along the storage period. The scores ranged between 8 (very good and

  5. Controle do escurecimento enzimático e da firmeza de polpa em pêssegos minimamente processados Control of enzymatic browning and flesh firmness in fresh-cut peaches

    Directory of Open Access Journals (Sweden)

    Amauri Costa da Costa

    2011-06-01

    Full Text Available O escurecimento enzimático e o amolecimento são as principais alterações que podem afetar pêssegos minimamente processados (MP. Objetivou-se avaliar a aplicação de L-cisteína (Cis, ácido L-ascórbico (AA e cloreto de cálcio (CC no controle do escurecimento enzimático e da perda de firmeza de polpa de pêssegos MP, cv. 'Esmeralda'. Os frutos foram processados e, após o fatiamento, imersos nos tratamentos: (I água (controle; (II AA+CC; (III Cis+CC; e, (IV Cis+AA+CC. Em seguida, as fatias foram acondicionadas em embalagens rígidas envoltas com filme PVC de 30µm de espessura e armazenadas durante seis dias a 4±1°C e 85±3% UR. As amostras foram avaliadas quanto aos aspectos físico-químicos, enzimáticos e sensoriais a cada dois dias. O tratamento Cis+AA+CC resultou em maiores valores de L* e h°, o que indica ter sido o mais eficaz na prevenção do escurecimento. Os tratamentos com L-cisteína resultaram em menor atividade da polifenoloxidase (PPO e o tratamento Cis+AA+CC foi o mais efetivo na contenção da atividade da peroxidase (POD, indicando que o melhor desempenho desse tratamento está associado à menor atividade de PPO e POD. A avaliação sensorial indicou que o tratamento Cis+AA+CC foi o mais eficiente, proporcionando a manutenção de características sensoriais aceitáveis aos pêssegos MP, cv. 'Esmeralda'.The enzymatic browning and firmness loss are the major changes that could affect fresh-cut peaches. The objective was to evaluate the application of L-cysteine (Cis, L-ascorbic acid (AA and calcium chloride (CC in the control of browning enzymatic and loss of firmness of minimally processed dried peaches, cv. 'Esmeralda'. The fruits were processed industrially and, after slicing, immersed in treatments: (I water (control; (II AA+CC; (III Cis+CC and (IV Cis+AA+CC. After, the slices were packed in packages sealed with PVC film 30µm thick and stored for six days at 4±1°C and 85±3% UR. The samples were evaluated

  6. Influência da embalagem de polietileno de baixa densidade e da temperatura na conservação do repolho minimamente processado Effects of low density polyethylene packaging and temperature in the conservation of fresh-cut cabbage

    Directory of Open Access Journals (Sweden)

    Maria M. Rinaldi

    2004-08-01

    Full Text Available Neste trabalho, foi estudado o efeito da embalagem de polietileno de baixa densidade e da temperatura de armazenagem na conservação de repolho minimamente processado. Os repolhos, previamente resfriados à temperatura de 10 ºC, foram submetidos à seleção, lavagem, corte em quatro partes com a retirada do talo central, sanitização, corte em tiras, enxágüe, centrifugação, pesagem e acondicionamento em embalagens plásticas de polietileno de baixa densidade (70 µm e armazenados em câmaras frias nas temperaturas de 1 e 10 ºC por 20 dias. Avaliaram-se dióxido de carbono, oxigênio e etileno na atmosfera interna da embalagem, bem como pH, acidez titulável, sólidos solúveis totais, vitamina C, perda de massa fresca e relação sólidos solúveis totais/acidez no repolho minimamente processado. O delineamento estatístico utilizado foi o inteiramente casualizado, com três repetições. Os parâmetros de análise, com exceção da vitamina C, perda de massa fresca e etileno, apresentaram variação significativa entre as temperaturas e dias de armazenamento. O repolho armazenado na temperatura de 1 ºC apresentou vida de prateleira ao redor de 15 dias, significativamente maior que a 10 ºC. Nesta última, no 8º dia de armazenamento, o produto encontrava-se totalmente deteriorado, sem condições de comercialização e consumo.This research studied the effect of low density polyethylene packaging and storage temperature on the preservation of fresh-cut (minimally processed cabbage. The cabbages, previously cooled to a temperature of 10 ºC, were selected, washed, cut in four parts (with the central stalk removed, sanitized, cut in strips, rinsed, put in the centrifuge, weighed and stored in plastic packaging of low density polyethylene (70 µm, and then stored in cold chambers at temperatures of 1 and 10 ºC for 20 days. The following aspects were evaluated: carbon dioxide, oxygen and ethylene in the internal atmosphere of the package

  7. 不同涂膜处理对鲜切铁棍山药品质的影响%Effect of Different Film Treatments on the Quality of Fresh-cut Dioscorea opposita Thunb.cv.Tiegun

    Institute of Scientific and Technical Information of China (English)

    庞凌云; 祝美云; 李瑜; 宋思聪

    2011-01-01

    以壳聚糖和海藻酸钠为保鲜剂,对鲜切铁棍山药进行涂膜保鲜,每隔2d测定失重率、Vc含量、可滴定酸含量、褐变度、可溶性固形物含量、多酚氧化酶活性等指标研究保鲜效果。同时以空白组、壳聚糖涂膜组作为对照。结果表明:壳聚糖浓度为1.2%的单一膜和1.2%壳聚糖、0.2%海藻酸钠复合膜都能有效地抑制鲜切铁棍山药的褐变,降低失重率,减少营养物质的损失。复合膜的保鲜效果最好。%Fresh-cut Dioscorea opposita Thunb.cv.Tiegun were coated with edible film composed of chitosan and sodium alginate.Every two days the weight loss rate,Vc content,titratable acid content,browning,soluble solid content,PPO activity were measured to study the preservation effect.The untreated group and chitosan single coating film group were compared.The results showed that the 1.2% chitosan single coating film and 1.2%-chitosan-0.2%-sodium-alginate composite film could effectively reduce the browning,weight loss rate and nutrient loss.The best preservation effects were achieved by compound coating film.

  8. Assessment of the Prevalence of Extended-Spectrum β-Lactamase-Producing Enterobacteriaceae in Ready-to-Eat Salads, Fresh-Cut Fruit, and Sprouts from the Swiss Market.

    Science.gov (United States)

    Nüesch-Inderbinen, Magdalena; Zurfluh, Kathrin; Peterhans, Sophie; Hächler, Herbert; Stephan, Roger

    2015-06-01

    Ready-to-eat (RTE) prepacked salads and fruit have been successfully marketed for the last decade in Switzerland and are increasingly important as a component of everyday diets. To determine whether extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae are present in RTE salads, fresh-cut fruit, and sprouts on the Swiss market, samples of 238 mixed and unmixed RTE produce from a large production plant and 23 sprout samples from two sprout farms were analyzed. Further, four samples from the production plant's recycled wash water, which is used for crop irrigation, were analyzed. Twelve (5%) of the 238 RTE products and one of the recycled wash water samples yielded ESBL-producing Enterobacteriaceae. Strain identification and PCR analysis of the blaESBL genes revealed Kluyvera ascorbata isolated from a tomato sample harboring a blaCTX-M-2-like gene; multidrug-resistant (MDR) Enterobacter cloacae detected in a chives sample imported from Spain harboring the clinically important bla(CTX-M-15) gene; and 10 Serratia spp. isolated from mixed salads (bla(FONA-2) and bla(FONA-2)-like genes were found in 6 [60%] and bla(FONA-4)-like and bla(FONA-5)-like genes were each found in 2 [20%] of the isolates). The recycled wash water sample tested positive for one extraintestinal pathogenic MDR Escherichia coli B2:ST131 harboring bla(CTX-M-27) and for one MDR E. coli A:ST88 containing bla(CTX-M-3). None of the sprout samples tested positive for ESBL-producing Enterobacteriaceae. Overall, the majority of the Enterobacteriaceae detected in Swiss RTE produce were environmental strains producing minor ESBLs. The detection of an isolate producing a clinically important ESBL in a single sample and of an international circulating pathogenic strain (B2:ST131) in recycled wash water highlights the importance of surveillance of fresh produce and of recycled wash water that will be reused for irrigation purposes.

  9. Quality of the fresh cut ‘Orange Flesh’ melon stored under modified atmosphere/ Qualidade do melão ‘Orange Flesh’ minimamente processado armazenado sob atmosfera modificada

    Directory of Open Access Journals (Sweden)

    Leandro Camargo Neves

    2007-08-01

    Full Text Available This work aimed at evaluate the effect of the fresh cut ‘Orange Flesh’ melon stored under modified atmosphere. The cubes of melons were sanitizationed with 100 mg L-1 of hypoclorite of sodium for one minute, washed, drained and wrapped with different concentrations of O2 and CO2 in plastic bags of polyethylene (Nylon Polished. They were appraised every other day for ten days as regards the firmness, total pectin, soluble pectin and activity of the polifenoloxidase and peroxidase. At the end of the conservation period, it was verified that melons sustained the firmest texture of the vegetable products under modified atmosphere, and the concentration of 5%O2 + 3% CO2 showed smaller content of total pectin and together with the concentration of 100% N2 the smallest content of soluble pectin, the polifenoloxidase activity was not verified as well as of the peroxidase.Este trabalho teve como objetivo avaliar o efeito da atmosfera modificada na qualidade do melão‘Orange Flesh’minimamente processado. Os cubos de melões foram sanificados com 100 mg L-1 de hipoclorito de sódio por um minuto, lavados, drenados e embalados com diferentes concentrações de O2 e CO2 em sacos plásticos de polietileno (Nylon Poli. Foram avaliados a cada dois dias durante dez dias quanto a firmeza, pectina total, pectina solúvel e atividade da polifenoloxidase e peroxidase. Ao final do período de conservação, os produtos vegetais com modificação da atmosfera mantiveram a textura mais firme e a concentração de 5%O2 + 3% CO2 apresentaram menor teor de pectina total e juntamente com a concentração de 100% N2 o menor teor de pectina solúvel e não apresentaram atividades de polifenoloxidase e peroxidase.

  10. Cold Plasma-activated hydrogen peroxide aerosol inactivates Escherichia coli 0157:H7, Salmonella Typhimurium, and Listeria innocua and maintains quality of grape tomato, spinach and cantaloupe

    Science.gov (United States)

    The purpose of this study was to investigate the efficacy of aerosolized hydrogen peroxide in inactivating bacteria and maintaining quality of grape tomato, baby spinach leaves and cantaloupe. Stem scar and smooth surfaces of tomatoes, spinach leaves, and cantaloupe rinds, inoculated with Escherich...

  11. Distribution and chemical fate of ³⁶Cl-chlorine dioxide gas during the fumigation of tomatoes and cantaloupe.

    Science.gov (United States)

    Smith, D J; Ernst, W; Giddings, J M

    2014-12-03

    The distribution and chemical fate of (36)Cl-ClO2 gas subsequent to fumigation of tomatoes or cantaloupe was investigated as were major factors that affect the formation of chloroxyanion byproducts. Approximately 22% of the generated (36)Cl-ClO2 was present on fumigated tomatoes after a 2 h exposure to approximately 5 mg of (36)Cl-ClO2. A water rinse removed 14% of the radiochlorine while tomato homogenate contained ∼63% of the tomato radioactivity; 24% of the radiochlorine was present in the tomato stem scar area. Radioactivity in tomato homogenate consisted of (36)Cl-chloride (≥80%), (36)Cl-chlorate (5 to 19%), and perchlorate (0.5 to 1.4%). In cantaloupe, 55% of the generated (36)Cl-ClO2 was present on melons fumigated with 100 mg of (36)Cl-ClO2 for a 2 h period. Edible cantaloupe flesh contained no detectable radioactive residue (LOQ = 0.3 to 0.4 μg/g); >99.9% of radioactivity associated with cantaloupe was on the inedible rind, with <0.1% associated with the seed bed. Rind radioactivity was present as (36)Cl-chloride (∼86%), chlorate (∼13%), and perchlorate (∼0.6%). Absent from tomatoes and cantaloupe were (36)Cl-chlorite residues. Follow-up studies have shown that chlorate and perchlorate formation can be completely eliminated by protecting fumigation chambers from light sources.

  12. Effect of Low Temperature Blanching Processing on the Quality for Muskmelon%低温漂烫处理对甜瓜品质的影响

    Institute of Scientific and Technical Information of China (English)

    高芙蓉; 陈存坤; 吴朝霞; 王文生; 冯叙桥; 于晋泽; 纪海鹏

    2015-01-01

    That the blanched treatments on fresh muskmelon and the temperature were at room temperature (23.7℃), 50℃and 65℃for 1 min were researched. The blanched and drained muskmelons were storaged in room temperature condition, and determined of various physiological indexes of muskmelon for every 5 d. The results indicated that:the preservation effects of all treated groups with blanching were better than the control group, especially the 50℃blanched group achieved the best preservation effect on muskmelons.%主要对新鲜甜瓜进行漂烫处理,处理水的温度分别为常温(23.7℃)、50℃和65℃,浸泡时间1 min。甜瓜漂烫后沥干,放置在常温(23.7℃)条件下,每隔5天测定甜瓜的各项生理指标。结果表明,漂烫处理能很好的延缓甜瓜果实衰老,其中50℃漂烫的甜瓜品质最好。

  13. The Effect of Short-term Storage and the Hot Water Treatment of Fresh-Cut Pepper Fruit cv. ‛Blondy F1’ and ‛Yecla F1’ on the Content of Bioactive Compounds and Antioxidant Properties

    Directory of Open Access Journals (Sweden)

    Szwejda-Grzybowska Justyna I.

    2016-12-01

    Full Text Available The aim of the experiment was to determine the changes in the contents of bioactive compounds and antioxidant/antiradical activity in fresh-cut fruits of sweet pepper cv. ‘Blondy F1’ and ‘Yecla F1’, depending on the postharvest treatment. Treatment with hot water and short-term storage decreased the content of bioactive compounds and antioxidant/antiradical activity of fruit peppers. The treatment with water at 55 °C for 12 sec. of fresh-cut fruits caused lower losses in content of bioactive compounds and antioxidant/antiradical activities than the treatment with water at 45 °C for 10 min. There was a significant correlation between the content of total polyphenols and antioxidant and antiradical activity of pepper fruits depending on the cultivar and the experimental season.

  14. Suitability analysis of fresh-cut vegetable processing for twenty main green capsicum cultivars in China%中国主栽青辣椒品种鲜切加工适宜性评价

    Institute of Scientific and Technical Information of China (English)

    沈月; 高美须; 杨丽; 赵鑫; 陈雪; 王志东; 李淑荣; 王丽

    2016-01-01

    In order to evaluate the suitability for fresh-cut vegetable processing of green capsicum, 20 main cultivars of green capsicum in China were collected and planted in greenhouse, and fruits were picked at the similar maturity level. Seventeen indices of the fruits were measured, which included physical and chemical indices (L*,a* andb *value, sensory evaluation score, product yield ratio, fruit hardness, pulp thickness, moisture content, ratio of sugar to acid, soluble solids, titratable acid), and functional indices (vitamin C content, total phenolics content, DPPH free radical scavenging activity (DPPH value), ferric ion reducing antioxidant power (FRAP value), ABTS+·radical scavenging activity (ABTS value) and beta carotene content). Significance analysis of basic measured data was carried out by SAS 9.2. Main evaluation indices were filtered by correlation analysis, principal component analysis and variable cluster analysis. The weight of main evaluation indices were determined by analytic hierarchy process (AHP). The suitability for fresh-cut vegetable processing of the 20 tested green pepper cultivars was appraised by grey relational degree analysis method. The basic data of 17 indices on 20 green pepper cultivars were measured and analyzed. Results of significance analysis showed that all indices varied from one tested green capsicum cultivar to another one excepted for moisture content, and the 3 indices which had the top coefficient of variation wereb*value, beta carotene content and FRAP value. Among all the tested 20 cultivars, “Longjiao No. 5” had the highest content of vitamin C, “Jingla No. 2” had the highest content of beta carotene and “Jingyanzhoupila” had the strongest antioxidant capacity. Results of correlation analysis showed that fruit hardness had significantly negative correlation with sensory evaluation score and the correlation coefficient was -0.68, however it had positive correlation with soluble solid content and the

  15. Fresh-Keeping Effect of Different Films on Fresh-Cut Pumpkin during Storage at Low Temperature%不同保鲜膜处理对低温贮藏下鲜切南瓜保鲜效果的影响

    Institute of Scientific and Technical Information of China (English)

    张丹丹; 杨绍兰; 吴昊; 张宏斌; 王成荣

    2012-01-01

    The present study aimed to evaluate the fresh-keeping effect of two types of edible multi-purpose preservative films(prepared mainly with chotisan and sodium alginate in the presence and absence of clove oil) on fresh-cut ‘Miben’ pumpkin.Fresh-cut ‘Miben’ pumpkin was coated with different films,and then stored at low temperature.Textural properties,ethylene production,and MDA content in fresh-cut pumpkin were determined during storage period.The results indicate that the two types of edible preservative films could obviously maintain textural properties,reduce MDA accumulation,and delay ethylene production in fresh-cut pumpkin.The edible film consisting of chotisan,sodium alginate and clove oil was more effective in maintain storage quality of fresh-cut pumpkin and prolonging its shelf-life.%以新鲜的"蜜本"南瓜为试验材料,研究可食性多功能防腐保鲜膜对鲜切南瓜的保鲜效果。将经切割后的南瓜用不同保鲜膜包裹处理,测定其硬度、弹性、咀嚼性、黏性、乙烯释放速率、丙二醛(MDA)的变化,探讨不同保鲜膜处理对鲜切南瓜的质地和生理生化代谢的影响。结果表明:不同保鲜膜处理能不同程度地保持鲜切南瓜的质地,延缓乙烯释放量的增加,减小MDA积累;其中,2号保鲜膜(主成分为壳聚糖、海藻酸钠、丁香油等)处理效果最好,有效地提高了鲜切南瓜贮藏期间的品质,并延长了其货架期。

  16. 鲜切果蔬中病原微生物污染及快速检测技术的研究进展%Research progress in rapid detection technology and microbial pathogens infection on fresh-cut fruits and vegetables

    Institute of Scientific and Technical Information of China (English)

    吕晓萌; 胡文忠; 冯叙桥; 姜爱丽; 郝江燕

    2013-01-01

    鲜切果蔬因具有较高的含水量,再加上较大的切割表面,极易引起病原微生物污染.病原微生物是影响鲜切果蔬安全问题的主要因素之一,在鲜切果蔬上市前对病原微生物进行检测能够保障鲜切果蔬食用的安全性.本文概述了鲜切果蔬中常见的大肠杆菌O157∶H7、沙门氏菌、单增李斯特菌、志贺氏杆菌的生长特点及影响因素等,并介绍了快速检测技术的研究进展及其在鲜切果蔬产业中的应用,包括聚合酶链反应法、酶联免疫法、ATP生物发光法、荧光原位杂交技术、全自动微生物检测系统.%With high moisture content and large cutting surface,fresh-cut fruits and vegetables are easy to cause infection of microbial pathogens.Microbial pathogen is one of the most important factors which effects on the safety of fresh-cut fruits and vegetables.The detection of microbial pathogens can ensure the safety of fresh-cut fruits and vegetables before consuming.In this paper,growth characteristics and influence factors of microbial pathogens on fresh-cut fruits and vegetables were reviewed,including Escherichia coil O157 ∶ H7,salmonella,Listeria monocytogenes,shigella.In addition,research progress of rapid detection were introduced,such as Polynerase Chain Reaction,Enzyme-Linked Immunosorbnent Assay,ATP bioluminescence assay,fluorescence in situ hybridization,automatic microbial detection system as well as in the application on fresh-cut fruits and vegetables industry.

  17. Conservação pós-colheita de espigas de milho verde minimamente processado sob diferentes temperaturas Post-harvest conservation of fresh-cut corn on the cob (Zea maiz L. under different temperatures

    Directory of Open Access Journals (Sweden)

    Alexandra Mara Goulart Nunes Mamede

    2009-02-01

    Full Text Available Objetivou-se, neste trabalho, avaliar o efeito de três temperaturas (5ºC, 8ºC e 11ºC, na qualidade de híbridos de milho verde (Zea maiz L. com endosperma normal, minimamente processado, durante oito dias de armazenamento, com avaliações a cada dois dias. Foram utilizadas espigas de dois híbridos, sendo um comercial da Sementes Agroceres (Ag 1051 e outro do programa de melhoramento da Embrapa Milho e Sorgo (Embrapa HT1. A temperatura de 5ºC foi a que melhor preservou a qualidade das espigas dos híbridos de milho verde estudados, por proporcionar perda de massa reduzida e manutenção dos teores de sólidos solúveis, frutose e glicose. O híbrido Ag 1051 apresentou menor perda de massa, maiores valores de umidade e maior teor de frutose. O Embrapa HT1 apresentou maiores valores iniciais e finais para os teores de sólidos solúveis e maior valor para a coloração b*. O valor L*, que indica quãoclaro e escuro é produto, também diminuiu ao longo do armazenamento, indicando escurecimento das espigas ao longo do armazenamento.This work had the aim of evaluating the effect of three temperatures (5ºC, 8ºC and 11ºC on the quality of fresh-cut corn on the cob (Zea maiz L. with normal endosperm, for 8 days, with analyses taken every two days. Corn on the cob of two hybrids was used, a commercial common type from Sementes Agroceres (Ag 1051 and the other from the breeding program Embrapa Milho e Sorgo (Embrapa HT1. The temperature of 5ºC was more efficient to preserve the quality of normal corn by promoting reduced mass loss and higher contents of soluble solids, fructose and glucose. The hybrid Ag 1051 presented lower mass loss, higher contents of moisture and higher content of fructose. The hybrid Embrapa HT1 presented higher initial and final values for soluble solids and higher b* value. The L* value also decreased along storage, indicating browning of the corns along the storage.

  18. Distribution and chemical fate of 36Cl-chlorine dioxide gas during the fumigation of tomatoes and cantaloupe

    Science.gov (United States)

    The distribution and chemical fate of 36Cl-ClO2 gas subsequent to fumigation of tomatoes or cantaloupe was investigated as was major factors that affect the formation of chloroxyanion byproducts. Approximately 22% of the generated 36Cl-ClO2 was present on fumigated tomatoes after a 2-hour exposure t...

  19. Practices and conditions which promote persistence of Listeria monocytogenes on equipment surfaces and transfer to cantaloupes in the packing environment

    Science.gov (United States)

    Introduction: Investigation of the 2011 U.S. listeriosis outbreak associated withcontaminated cantaloupes revealed that transfer of L. monocytogenes(Lm) from equipment surfaces to melons in the packing facility was a potential route of contamination. Purpose:This study examined the persistence of Lm...

  20. Effects of Plastic Box Modified Atmosphere Storage on the Antioxidant System of Fresh-cut Fuji Apple%箱式气调贮藏对鲜切富士苹果抗氧化系统的影响

    Institute of Scientific and Technical Information of China (English)

    姜爱丽; 胡文忠; 代喆; 田密霞; 刘程惠

    2011-01-01

    以富士苹果为试材,研究了鲜切富士苹果在5℃的5%O2+5%CO:或5%02+10%CO2箱式气调贮藏条件下抗氧化系统的变化情况。每3d测定1次酶促防御系统的酶活性和非酶促防御系统的抗氧化物质的含量,并测定呼吸速率、腐烂率和褐交情况。结果表明:与对照相比,2种CO2浓度的箱武气调贮藏条件均可启动酶促防御系统,使过氧化物酶(POD)、过氧化氢酶(CAT)和超氧化物歧化酶(SOD)的活性得到提高,同时也加速了非酶促防御系统抗氧化物质的消耗,降低了总酚和Vc含量以及贮藏中后期的还原型谷胱甘肽(GSH)含量。2种浓度的CO2处理可有效减慢呼吸速率,抑制腐烂的发生并有效降低褐变程度,其中5%0:+5%CO2更有利于鲜切富士苹果褐交的控制,而5%0,+10%CO2更有利于抑制腐烂。%In order to determine the effects of plastic box modified atmosphere storage on the antioxidant system of fresh-cut Fuji apple, the condition of 5% 02 +5% C02 and 5% 02 + 10% CO= atmosphere at 5℃ were established in this experiment. Meanwhile, the activity of enzymatic defense system, the concentration of non - enzyme antioxidants as well as respiration rate, rot rate and browning degree were measured every 3 d. The results indicated that two kinds of plastic box modified atmosphere with high CO2 were all able to start the enzymatic defense system. There- fore, not only the peroxidase (POD), catalase (CAT) and superoxide dismutase (SOD) activities were increased, but the consumption of antioxidant in non-enzymatic defense system were also accelerate. The total phenolics, Vc and reduced glutathione (GSH) content were decreased. Moreover, 5 % 02 + 5 % CO2 and 5 % 02 +10 % C02 effectively slowed down the respiration rate, inhibited the occurrence of decay and reduced the degree of browning. Apples stored with 5 % 02 +5 % CO2 was better in

  1. Revestimento ativo de amido na conservação pós-colheita de pera Williams minimamente processada Starch-based edible coating on extending shelf life of fresh-cut pear

    Directory of Open Access Journals (Sweden)

    Diego Alvarenga Botrel

    2010-08-01

    significantly more firms (P<0,05 compared to treatments C and T1. Cysteine action over enzymatic browning inhibition was observed in treatments T2 and T3 which do not differed significantly each other (P≥0,05 to ∆E values however these were significantly lower than control (C. At time 6, decimal reduction on psychrotrophs counting reached 3,03 and 2,43 to T3 e T2 compared to control. Enterobacteriaceae counting showed similar behavior where the reduction values were 3,16 and 3,05 to T2 e T3 compared to control. It was verified that using the studied edible coating on fresh cut pear can extend its shelf life.

  2. Qualidade de produto minimamente processado à base de abóbora, cenoura, chuchu e mandioquinha-salsa Maintenance of the quality of fresh-cut products made up of pumpkin, carrot, chayote, and arracacha (peruvian carrot

    Directory of Open Access Journals (Sweden)

    Juliana Alvarenga Alves

    2010-09-01

    Full Text Available O objetivo deste trabalho foi avaliar a qualidade de produto minimamente processado, à base de quatro hortaliças - abóbora, cenoura, chuchu e mandioquinha-salsa, armazenado a 5 ºC por 8 dias. Observou-se que os teores de umidade, fibra, proteína, cinza e fração glicídica das quatro hortaliças não foram afetados pelo tempo de armazenamento, entretanto o teor de extrato etéreo aumentou. Durante o armazenamento, o teor de vitamina C e de acidez titulável diminuiu em todas as hortaliças. O teor de β-caroteno do chuchu não alterou, entretanto, aumentou na abóbora, na cenoura e na mandioquinha-salsa. O pH das quatro hortaliças aumentou com o armazenamento. Os teores de sólidos solúveis da cenoura e da mandioquinha-salsa aumentaram, não sendo afetados na abóbora e no chuchu. As notas de aparência do "mix" não foram inferiores a 7 (gostei moderadamente, durante o armazenamento. Os coliformes a 35 ºC presentes no "mix" aumentaram e não foi constatada a presença de coliformes a 45 ºC e Salmonella sp. em nenhum tempo avaliado. Conclui-se que a vida útil, entendida sob os aspectos nutricionais, sensoriais e microbiológicos, pode ser estabelecida em 8 dias sob refrigeração para abóbora, cenoura, chuchu e mandioquinha-salsa submetidos ao processamento mínimo.The goal of this study was to evaluate the quality of fresh-cut products made up of four vegetables: pumpkin, carrot, chayote, and arracacha (peruvian carrot stored at 5 ºC for 8 days. It was observed that the contents of humidity, fiber, protein, ash, and glucidic fraction of the four vegetables were not affected by the time of storage; however, the content of ethereal extract increased. During storage, the content of vitamin C and titratable acidity decreased in all the vegetables. The content of β-carotene of chayote did not change, whereas the content in the pumpkin, carrot, and the peruvian carrot increased. The pH of the four vegetables increased during storage

  3. Influência do tipo de corte na qualidade de abobrinha 'Menina Brasileira' minimamente processada Influence of cut type on quality of cv. 'Menina Brasileira' summer squash fresh-cut

    Directory of Open Access Journals (Sweden)

    Brígida M Vilas Boas

    2006-06-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito do tipo de corte na manutenção da qualidade de abobrinhas 'Menina Brasileira' minimamente processadas armazenadas sob refrigeração. As abobrinhas foram fatiadas ou raladas, sendo sanificadas com solução de hipoclorito de sódio 50 mg L-1 por 10 minutos. Estas foram acondicionadas em bandejas de polipropileno envoltas com filme de PVC (0,020 mm de espessura, e armazenadas em câmara fria (6ºC e 95% UR por 12 dias. As seguintes variáveis foram avaliadas: perda de massa, pH, sólidos solúveis (SS, valores L*, C* e hº, aparência e cor. O experimento foi conduzido em delineamento inteiramente casualizado em esquema fatorial (2x5, sendo dois tipos de corte (fatiada e ralada e cinco tempos de armazenamento (0, 3, 6, 9 e 12 dias. A perda de massa foi pequena, atingindo valores máximos de 1,5% para a abobrinha ralada. Os valores de pH foram menores a partir do 6º dia nas abobrinhas raladas quando comparadas às fatiadas. Após o 3º dia de armazenamento, as abobrinhas raladas apresentaram menores valores de SS em relação às abobrinhas fatiadas. Maiores valores L* foram encontrados nas abobrinhas fatiadas, observando-se um acréscimo ao longo do armazenamento. Abobrinha fatiada apresentou menores perdas de coloração, baseado nos valores h° e C* e melhor aceitabilidade quando avaliada sensorialmente em relação à ralada, com decréscimos nas notas com o armazenamento. O tipo de corte influencia a vida de prateleira de abobrinha minimamente processada sendo que as formas fatiada e ralada mantêm a aparência e as características físico-químicas até o 12º dia de armazenamento.The goal of this work was to evaluate the effect of the type of cut the on maintenance quality of fresh-cut 'Menina Brasileira' summer squash stored under refrigeration. Summer squashes were sliced or grated and sanitized with sodium hypochloride solution at 50 mg L-1 for 10 minutes. They were placed in

  4. Identification of Salmonella serotypes isolated from cantaloupe and chile pepper production systems in Mexico by PCR-restriction fragment length polymorphism

    National Research Council Canada - National Science Library

    Gallegos-Robles, Miguel A; Morales-Loredo, Alberto; Alvarez-Ojeda, Genoveva; Vega-P, Adrián; Chew-M, Yazmín; Velarde, Sixto; Fratamico, Pina

    2008-01-01

    .... A total of 55 samples were obtained from both production systems. Twelve and 10 samples from the cantaloupe and chile pepper production systems, respectively, tested positive for Salmonella according to a traditional culture method...

  5. 壳聚糖植酸天然复合涂膜对鲜切莲藕保鲜效果的研究%Study of Natural Film with Chitosan Combining Phytic Acids on Preservation of Fresh-cutting Lotus Root

    Institute of Scientific and Technical Information of China (English)

    于有伟; 李惠; 邸金花; 任引哲

    2012-01-01

    Using chitosan, phytic acid and their combination to film fresh-cutting lotus root, the effect of different film on preservation was studied. Hie result showed that compound film with 1% chitosan and 1% phytic acid could an reduce the weight loss rate and MDA content of fresh-cutting lotus root, postpone browning, restrain the activities of POD, PPO and PAL, and keep the content of vitamin C and polyphenol at relatively high level. At the 8 th day, the weight loss rate of fresh-cutting lotus root with compound film was one half of control, MDA content was lower 18.8% and L value was higher 51.2% than control. Compound film with chitosan and phytic acid is a simple but effective method to preserve fresh-cutting lotus root, which is superior to single chitosan or phytic acid%采用1%壳聚糖、1%植酸和壳聚糖植酸复合涂膜处理鲜切莲藕,研究不同处理对鲜切莲藕贮存效果的影响.研究结果表明,复合涂膜处理能够降低鲜切莲藕的失重率和MDA含量,延缓藕片的褐变,抑制POD、PPO、PAL的活性,同时使维生素C和多酚含量维持在较高水平.贮存至第8天,复合涂膜的鲜切莲藕失重率为对照的1/2,MDA含量比对照低18.8%,L值比对照高51.2%.壳聚糖植酸复合涂膜是一种简便有效的贮存鲜切莲藕的方法,效果优于壳聚糖或植酸单一处理.

  6. Effect of gamma radiation on the content {beta}-carotene and volatile compounds of cantaloupe melon

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Stefania P. de; Cardozo, Monique; Lima, Keila dos S.C.; Lima, Antonio L. dos S., E-mail: keila@ime.eb.br, E-mail: santoslima@ime.eb.br [Departamento de Quimica - IME - Instituto Militar de Engenharia, RJ (Brazil)

    2011-07-01

    The Japanese melon or cantaloupe (Cucumis melo L.) is characterized by fruits with almost 1.0 Kg, pulp usually salmon and musky scent. The fruits when ripe are sensitive to post harvest handling. This low transport resistance and reduced shelf-life makes it necessary to delay the ripening of fruit. In this way the use of irradiation technique is a good choice. Irradiation is the process of exposing food to high doses of gamma rays. The processing of fruits and vegetables with ionizing radiation has as main purpose to ensure its preservation. However, like other forms of food processing, irradiation may cause changes in chemical composition and nutritional value. This study aims to assess possible changes in carotene content and volatile compounds caused by exposure of cantaloupe melon fruit to gamma irradiation. Irradiation of the samples occurred in Centro Tecnologico do Exercito (Guaratiba-RJ), using Gamma irradiator (Cs{sub 137} source, dose rate 1.8 kGy/h), being applied 0.5 and 1.0 kGy doses and separated a control group not irradiated. Carotenoids were extracted with acetone and then suffered partition to petroleum ether, solvent was removed under nitrogen flow and the remainder dissolved in acetone again. The chromatographic analysis was performed using a Shimadzu gas chromatograph, with C30 column. For volatile compounds, we used gas chromatography (GC) associated with mass (MS). As a result, it was verified in analysis of carotenoids that cantaloupe melon is rich in {beta}-carotene. Both total content of carotenoids and specific {beta}-carotene amount wasn't suffer significant reduction in irradiated fruits at two doses, demonstrating that the irradiation process under these conditions implies a small loss of nutrients. The major volatile compounds were: 2-methyl-1-butyl acetate, ethyl hexanoate, n-hexyl acetate, benzyl acetate, 6-nonenyl acetate and {alpha} -terpinyl acetate. For all compounds we observed an increase in the volatile content in 0.5 k

  7. Efeito de revestimentos comestíveis na conservação de mamões minimamente processados Effect of edible coatings on the preservation of fresh cut papayas

    Directory of Open Access Journals (Sweden)

    Juliana Moreno Trigo

    2012-06-01

    Full Text Available Avaliou-se o efeito de revestimentos à base de carboidratos nas características microbiológicas, físicas, físico-químicas e sensoriais de mamão Formosa minimamente processado (MP, armazenado sob refrigeração. Após tratamento com cloreto de cálcio, os frutos descascados e cortados foram imersos em soluções de amido de arroz (AA 3%; alginato de sódio (AS 0,5%; carboximetilcelulose (CMC 0,25%, e armazenados a 5 ºC e 90% de UR. Os produtos foram avaliados nos dias 1, 3, 6, 9, 12 e 15. O uso de revestimentos à base de AA, AS e CMC em mamões MP resultou em menor contagem de coliformes totais que o controle. Mamões revestidos com AA e CMC apresentaram redução e aumento do processo respiratório, respectivamente. Os frutos revestidos apresentaram menores teores de sólidos solúveis e seus valores de pH se tornaram menores após o 9º dia de armazenamento. O uso da CMC como revestimento proporcionou, no 15º dia, maior firmeza da polpa. As variações nos parâmetros de cor (Luminosidade, Hue e Croma não comprometeram a qualidade sensorial do mamão MP. Os atributos sensoriais dos mamões com revestimentos não diferiram do controle durante os 15 dias de estudo. Como a maioria dos efeitos positivos das coberturas ocorreu aos 12º e 15º dias e, considerando-se o custo da tecnologia e o preço dos revestimentos, a melhor opção, até 9 dias de armazenamento, consiste em apenas sanitizar os frutos, como feito no controle. Se o interesse for preservar a vida útil por um período maior, até 15 dias, os revestimentos utilizados podem ter resultados satisfatórios, desde que respeitadas as condições de estocagem utilizadas no estudo.The experiment evaluated the effects of carbohydrate-based coatings on the microbiological, physical, physical-chemical and sensory properties of the fresh cut (FC Formosa papaya stored under refrigeration. After treatment with calcium chloride, peeled and sliced portions of the fruit were immersed in 3

  8. Avaliação de diferentes sanificantes na qualidade microbiológica de mandioquinha-salsa minimamente processada Evaluation of different sanitizers on the microbiological quality of fresh-cut peruvian carrot

    Directory of Open Access Journals (Sweden)

    Elisângela Elena Nunes

    2010-08-01

    were utilized. Detergent and water were used for the surface cleaning of the roots. Afterwards, the roots were divided into two groups: control (not sanitized and sanitized, for immersion into 100mg.L-1 sodium dichloro isocyanurate for 15 minutes. They were then peeled, sliced into rings and immersed into the following sanitizers: sodium hypochlorite (25, 50 and 100 mg.L-1 for 10 minutes, hydrogen peroxide (3 and 6%, for 5 minutes and sodium dichloro isocyanurate (50, 100 and 200 mg.L-1 for 10 minutes; packed and stored in cold chamber ( 5 ± 1ºC and 98% RH for 15 days. The following analyses were performed every 3 days: pH, titrable acidity, soluble solids, coliforms determination and search for Salmonella. The pH, AT and SS variables were not affected by the used treatments. The presence of coliforms at 45ºC and Salmonella was not detected during the storage of either control or sanitized fresh-cut Peruvian carrots and low counts for coliforms at 35ºC were found. The sanitization of the produce before processing with 100mg.L-1 sodium dichloro isocyanurate and hygienic-sanitary conditions during processing allow obtaining a produce with microbiological standard according to the food legislation until the 15th day of storage.

  9. Adição de agentes antiescurecimento, antimicrobiano e utilização de diferentes filmes plásticos, em mamão minimamente processado Adition of antibrowning and antimicrobes agents and utilization of different plastic films in fresh cut processing of papaya

    Directory of Open Access Journals (Sweden)

    Álvaro Silva Lima

    2005-04-01

    Full Text Available O mamão é uma fruta climatérica largamente produzida no Brasil que pode ser submetida à aplicação dos procedimentos de processamento mínimo. Neste trabalho, conduziram-se experimentos nos quais foram avaliadas a ação do tipo de embalagem e a aplicação de produtos químicos na manutenção da qualidade físico-química e sensorial da fruta com o tempo de armazenamento. Observou-se que a melhor condução do processamento foi obtida quando se fazia a embalagem com filme de PVC e aplicação de sorbato de potássio (0,75%, p/v, pois não produziu perda da qualidade sensorial ao mamão processado.Papaya is a climateric fruit widely produced in Brazil and can easily be submitted to fresh cut processing. In this work, experiments were conducted to evaluate the action of the type of packing and the application of chemical products in the increase of the sensorial quality of fresh-cut papaya. It was observed that the best conduction of the processing was obtained using PVC film packing and potassium sorbate (0.75%, w/v, because it didn't produce the lost of the sensorial quality.

  10. Effect of Harvest Time and L-Cysteine as an Antioxidant on Flesh Browning of Fresh-Cut Cherimoya (Annona cherimola Mill. Efecto del Momento de Cosecha y L-Cisteína como un Antioxidante en el Pardeamiento de Pulpa de Chirimoya (Annona cherimola Mill. Precortada

    Directory of Open Access Journals (Sweden)

    Reinaldo Campos-Vargas

    2008-09-01

    Full Text Available Browning development is the most important factor limiting the quality of fresh-cut cherimoya (Annona cherimola Mill.. However, there is little information available about its causes and methods of control. The effectiveness of L-cysteine (0.125, 0.25 and 0.5% in fresh-cut cherimoya harvested on two occasions (October and November and stored for 6 and 12 days at 0 °C was studied. In order to understand the biological basis of browning, polyphenol oxidase (PPO enzyme activity and total phenolic content in fresh-cut pieces were measured. Quality measurements and sensory analysis indicated that 0.5% L-cysteine was somewhat effective in reducing browning development, without affecting other quality attributes. In terms of physiological parameters, PPO activity did not show differences between mature (at harvest and ripe fruit (at processing in both harvest times, but cherimoya fruits picked in November presented lower PPO activity than fruit from October. In general, PPO activity and total phenolic content of L-cysteine treated fruits did not show consistent differences with untreated fruit at 6 or 12 days at 0 °C. PPO activity analyses demonstrated that PPO activity was higher in the outer part of cherimoya flesh compared to the middle or inner sector. These results would support the possibility of using L-cysteine as a postharvest treatment to reduce browning development in fresh-cut cherimoya.El desarrollo de pardeamiento es uno de los factores limitantes en la calidad de chirimoya (Annona cherimola Mill. precortada (fresh-cut. No obstante, existe poca información disponible en relación a sus causas y métodos de control en esta fruta. Se estudió la efectividad de L-cisteína (0,125; 0,25 y 0,5% en chirimoya precortada cosechada en dos oportunidades (octubre y noviembre y almacenada por 6 y 12 días a 0 ºC. Con el objetivo de conocer las bases biológicas del pardeamiento, se estudió la actividad de polifenol oxidasa (PPO y contenido de

  11. Identification of Salmonella serotypes isolated from cantaloupe and chile pepper production systems in Mexico by PCR-restriction fragment length polymorphism.

    Science.gov (United States)

    Gallegos-Robles, Miguel A; Morales-Loredo, Alberto; Alvarez-Ojeda, Genoveva; Vega-P, Adrián; Chew-M, Yazmín; Velarde, Sixto; Fratamico, Pina

    2008-11-01

    A study was conducted in 2006 to determine the prevalence of Salmonella on three cantaloupe farms in Matamoros, Coahuila, Mexico, and on one farm that cultivates chile peppers var. Bell in Culiacán, Sinaloa, Mexico. Samples from cantaloupe farms consisted of cantaloupe rinses, irrigation water, water from furrows in the field, and workers' hands. Samples from the chile pepper farm consisted of rinses of chile peppers obtained at the field, pepper rinses obtained at the packing house, and irrigation water from the field. A total of 55 samples were obtained from both production systems. Twelve and 10 samples from the cantaloupe and chile pepper production systems, respectively, tested positive for Salmonella according to a traditional culture method. The difference between the proportion of Salmonella-positive samples from the cantaloupe production system (12 of 28 = 0.43) and the chile pepper production system (10 of 27 = 0.37) was not statistically significant (P > 0.05). A PCR-restriction fragment length polymorphism (RFLP) method based on the fliC gene was used to determine the serotype of the isolates. Salmonella Typhimurium was the only serotype found associated with the cantaloupe production system, whereas both Salmonella Typhimurium and Enteritidis serotypes were found associated with the chile pepper production system. Results showed that 91% (20 of 22) and 9% (2 of 22) of the isolates from both agricultural systems matched with the Salmonella Typhimurium and Salmonella Enteritidis reference strain restriction profiles, respectively. This study demonstrates the utility of the PCR-RFLP technique for determining the serotypes of Salmonella isolates obtained from cantaloupe and chile pepper production systems.

  12. A Study of Oxalate-Induced Systemic Resistance of Muskmelon to Squash Mosaic Virus%草酸诱导甜瓜对南瓜花叶病毒的系统抗性的研究

    Institute of Scientific and Technical Information of China (English)

    赵荣乐

    2000-01-01

    By treatment with oxalate muskmelon cultivar "Wangwenxiang", which is sensitive to squash mosaic virus (SqMV), develops systemic resistance to SqMV significantly. The challenge inoculation experiments indicate that the symptom of oxalate-treated plants gets much slighter, the virus content is only 4 % reduced to. The peroxidase activity increases by five times, three new isoperoxidases are induced, and lignin content increases by 82.9 %. These results indicate that oxalate induces systemic resistance of muskmelon to SqMV while it induces increase of peroxidase activity, new isoperoxidases and content of lignin in the plants treated with oxalate.

  13. Effect of ozone water combined with modified atmosphere packaging on preservation of fresh-cut Hang cabbage%臭氧水清洗结合气调包装对鲜切杭白菜保鲜效果的研究

    Institute of Scientific and Technical Information of China (English)

    雷昊; 谢晶; 乔永祥; 张栓栓

    2017-01-01

    以1.8 mg/L臭氧水清洗的鲜切杭白菜为试验材料,研究不同气体组分的气调包装(CK为空气;A为5% O2+5% CO2+90% N2;B为5% O2+10% CO2+85% N2;C为10% O2+5% CO2+85% N2;D为10% O2+10% CO2+80% N2)对鲜切杭白菜保鲜效果的影响.结果表明:B组低氧高二氧化碳的包装能有效地抑制鲜切杭白菜上微生物的生长,保持其较好的感官品质,同时延缓VC、叶绿素及可溶性固形物含量的降低,防止杭白菜过快失水,有效地保证鲜切杭白菜的货架期在15 d以上.%Fresh-cut hang cabbage cleaned by 1.8 mg/L ozone water was selected as the experimental material, the effect of keeping fresh on fresh-cut Hang cabbage was studied by different gas composition modified atmosphere packages, such as CK for air, A for 5% O2+ 5% CO2 +90% N2, B for 5% O2+10% CO2+85% N2, C for 10% O2+5% CO2+85% N2, D for 10% O2+10% CO2+80% N2.It showed that the 5% O2+10% CO2+85% N2, low oxygen and high carbon dioxide packaging could effectively inhibit the growth of microorganisms, keep good sensory quality, and delayed the decreasing of vitamin C, chlorophyll and soluble solids content, prevented the cabbage excessive water loss, which effectively guaranteed the shelf life of fresh-cut Hang cabbage to more than 15 d.

  14. K+ and Na+ Contents in Plants of Muskmelon Varieties under NaCl Stress%NaCl对不同甜瓜品种植株中K+和Na+含量的影响

    Institute of Scientific and Technical Information of China (English)

    王澍; 朱春燕; 俞晨玺; 沈丹婷; 王黎敏; 牛庆良; 黄丹枫

    2011-01-01

    The absorbability and distributions of Na+ ,K+ in different organs of four muskmelon varieties, salty tolerance varieties (Haimisihao, Bingxuecui) and salty sensitive varieties ( Yulu、 Xiulv), were investigated under NaCl stress (75,150,225,300 mmol/L) in artificially controlled conditions. The results indicated that the Na+ content in the root,stalk,leave and fruit of the tolerant muskmelon was significantly lower than those of salt sensitive muskmelon with the increase of the NaCl concentraion. However, the K+ content in salt tolerant muskmelon root was significantly lower than that in the salt sensitive muskmelon root. Na+/K+ values in the stalk, leave and fruit of salty tolerant muskmelon was significantly lower than that in sensitive muskmelon though no significant difference of Na+/K+ was found in the root of salty tolerant and salt sensitive muskmelon. No significant difference was indicated in the amount of dry matter including root,shoot,leaves and fruits of all salty tolerant muskmelon. The minimum decreased weight of single fresh fruit and dry matter was detected in the salty tolerant muskmelon "Bingxuecui" while the maximum decreased weight of single fresh fruit and dry matter was found in the sensitive tolerant muskmelon "Xiulv".%用75、150、225和300 mmol/L的NaCl对耐盐性不同的4个甜瓜品种——耐盐品种:“海蜜四号(网纹)”、“冰雪脆(光皮)”,敏感品种:“玉露(网纹)”、“秀绿(光皮)”进行处理,研究不同甜瓜品种根、茎、叶和果实中的K+和Na+含量的变化.结果表明:随着NaCl浓度升高,甜瓜耐盐品种根、茎、叶和果实中Na+含量均低于盐敏感品种,而根中K+含量降低幅度显著小于盐敏感品种;耐盐品种茎、叶和果实中Na+/K+比值显著低于盐敏感品种,而根中无显著变化.从植株干重中可知,耐盐品种在任何浓度下都无显著变化,而盐敏感品种都下降.耐盐品种“冰雪脆”的单果鲜重和干重下降幅度最

  15. Chlorophenoxyacetic acid and chloropyridylphenylurea accelerate translocation of photoassimilates to parthenocarpic and seeded fruits of muskmelon (Cucumis melo).

    Science.gov (United States)

    Li, Xin-Xian; Kobayashi, Fumiyuki; Ikeura, Hiromi; Hayata, Yasuyoshi

    2011-06-15

    We compared the effect of p-chlorophenoxyacetic acid (p-CPA) and 1-(2-chloro-4-pyridyl)-3-phenylurea (CPPU) on parthenocarpic and seeded muskmelon (Cucumis melo) fruits in regards to fruit development and the transport of photoassimilates from leaves exposed to ¹⁴CO₂ to the developing fruits. Ten days after anthesis (DAA), the fresh weight, total ¹⁴C-radioactivity and contents of ¹⁴C-sucrose and ¹⁴C-fructose were higher in the CPPU-induced parthenocarpic fruits than in seeded fruits. However, at 35 DAA, fresh weight and sucrose content in mesocarp, placenta and empty seeds of the parthenocarpic fruits were lower than in seeded fruits. Also, total ¹⁴C-radioactivity and ¹⁴C-sugar content of the parthenocarpic fruits were lower as well as the translocation rate of ¹⁴C-photoassimilates into these fruits. Application of p-CPA to the parthenocarpic fruits at 10 and 25 DAA increased fresh weight and sugar content. Moreover, these treatments elevated the total ¹⁴C-radioactivity, ¹⁴C-sucrose content and the translocation rate of ¹⁴C-photoassimilates. The ¹⁴C-radioactivity along the translocation pathway from leaf to petiole, stem, lateral shoot and peduncle showed a declining pattern but dramatically increased again in the fruits. These results suggest that the fruit's sink strength was regulated by the seed and enhanced by the application of p-CPA.

  16. Physiological analysis and transcriptome comparison of two muskmelon (Cucumis melo L.) cultivars in response to salt stress.

    Science.gov (United States)

    Wang, L M; Zhang, L D; Chen, J B; Huang, D F; Zhang, Y D

    2016-09-19

    Melon (Cucumis melo L.) is an important vegetable crop that ranks second in salt tolerance among the Cucurbitaceae. Previous studies on the two muskmelon cultivars 'Bing XueCui' (BXC) and 'Yu Lu' (YL) revealed that they had different characteristics under salt stress, but the molecular basis underlying their different physiological responses is unclear. Here, we combined a physiological study with a genome-wide transcriptome analysis to understand the molecular basis of genetic variation that responds to salt stress in the melon. BXC performed better under salt stress than YL in terms of biomass and photosynthetic characteristics, because it exhibited less reduction in transpiration rate, net photosynthesis rate, and stomatal conductance under 150-mM NaCl stress than YL. A transcriptome comparison of the leaves of the cultivars revealed that 1171 genes responded to salt stress in BXC while 1487 genes were identified as salt-stress-responsive in YL. A real-time polymerase chain reaction analysis of 12 of the responsive genes revealed that there was a strong, positive correlation with RNA sequencing data. The genes were involved in several pathways, including photosynthesis, the biosynthesis of secondary metabolites, metabolism, and plant hormone signal transduction, and their expression levels differed between the two cultivars in response to salt stress. This study provides a molecular perspective of two melon cultivars in response to salt stress, and its results could be used to investigate the complex molecular mechanisms underlying salt tolerance in the melon.

  17. Yield and apparent dry matter and nitrogen balances for muskmelon in a long-term comparison between an organic and a conventional low input cropping system

    Directory of Open Access Journals (Sweden)

    Michela Farneselli

    2015-09-01

    Full Text Available Nine-year yields and apparent balances of dry matter and nitrogen (N are reported for muskmelon cultivated in a long-term comparison trial between an organic and a conventional low input system in Central Italy. In every year, yield, above ground biomass and N accumulation of each cash crop, green manure and weeds, and the partitioning between marketable yield and crop residues were determined. Apparent dry matter and nitrogen balances were calculated at the end of each crop cycle by taking into account the amounts of dry matter and ex novo N supplied to the system as green manure legume Ndfa (i.e., an estimate of N derived from the atmosphere via symbiotic fixation and fertilisers, and those removed with marketable yield. Differences between systems varied across years. On average, organic muskmelon yielded 16% less than the conventional one, while the fruit quality was similar in the two cropping systems. Fruit ripening began one week later and it was more scaled than in the crop grown conventionally. This was the consequence of a slow initial growth of the organic crop, due to inadequate green manure N total supply or timing of N release. Moreover such a wide spaced crop (0.5 plants m–2, in rows 2 m apart was not efficient in intercepting N released from green manure biomass incorporated broadcast. Compared to the conventional crop management, the organic crop management resulted in much higher organic matter supply to the soil and in higher residual N after harvest. Thus, the choice of cultivating wheat just after melon to prevent postharvest residual N loss appears a key strategy especially in organic systems. Fall-winter green manure crops contributed to the self-sufficiency of the organic system by supplying muskmelon with either N absorbed from the soil or ex novo legume Ndfa.

  18. Effect of methyl jasmonate pre-treatment on quality and antioxidant activity of fresh-cut pitaya fruit%茉莉酸甲酯预处理对鲜切火龙果品质和抗氧化活性的影响

    Institute of Scientific and Technical Information of China (English)

    李晓安; 韩聪; 高梵; 龙清红; 金鹏; 郑永华

    2015-01-01

    目的:研究茉莉酸甲酯(MeJA)预处理对鲜切火龙果在10℃,4 d贮藏期间品质和抗氧化活性的影响。方法完整火龙果先用浓度分别为0、1、10和100μmol/L 的MeJA熏蒸,再进行鲜切处理,测定其贮藏期间的品质和理化指标。结果100μmol/L的MeJA熏蒸处理能最显著地诱导鲜切火龙果贮藏期间总酚、总黄酮等次级代谢产物的积累,提高鲜切火龙果贮藏期间DPPH自由基清除能力。MeJA预处理能有效地促进鲜切火龙果贮藏期间超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和谷胱甘肽还原酶(GR)等抗氧化酶活性的提高。同时, MeJA预处理抑制了可滴定酸(TA)含量的下降,对可溶性固形物(TSS)、维生素C含量无不良影响。结论100μmol/L的MeJA预处理能较好地保持鲜切火龙果的品质,并有效地提高其抗氧化能力,最终提高鲜切火龙果的营养品质。%Objective To investigate the effects of methyl jasmonate (MeJA) pre-treatment on food quality and antioxidant activity in fresh-cut pitaya (Hylocereus undatus) during storage at 10℃ for up to 4 days. Methods Whole pitaya was pre-treated with 0, 1, 10, and 100μmol/L of MeJA, then was cut into pie-cuts, and its quality and physicochemical indexes during storage were measured.Results MeJA 100μmol/L pre-treatment had the most significant inducement effect on the accumulation of the secondary metabolites such as total phenolics and total flavonoids, and significantly enhanced 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity of fresh-cut pitaya during storage. MeJA pre-treatment could significantly promote the increase of antioxidant enzymes activities such as SOD, CAT and GR. Meanwhile, this pre-treatment inhibited the decrease of titratable acid, and had no bad effect on the total soluble solid and vitamin C. Conclusion The MeJA 100μmol/L pre-treatment has a promising application prospect in food quality maintenance of fresh-cut pitaya and markedly

  19. Research progress in mechanical wounding stimulation signal molecules transduction and defensive reaction for fresh-cut fruits and vegetables%鲜切果蔬机械伤害刺激信号分子转导及防御反应的研究进展

    Institute of Scientific and Technical Information of China (English)

    闫媛媛; 胡文忠; 姜爱丽; 陈晨

    2015-01-01

    鲜切果蔬在加工过程中会使果蔬受到机械损伤,组织结构遭到破坏,极易发生褐变与受到微生物侵染,从而加速果蔬组织的衰老和腐败。机械伤害刺激信号分子的产生、运转、感知、接受和转导,以激活受伤害诱导的防卫基因表达,进而诱发鲜切果蔬整体协调产生防御反应。茉莉酸类、水杨酸、乙烯、脱落酸和系统素信号分子诱导果蔬防御反应可减轻机械损伤对鲜切果蔬品质的影响,能够有效抑制微生物对受伤部位的侵染以及果蔬组织内部的酶促褐变,改善果蔬贮藏品质。本文从机械伤害刺激信号分子茉莉酸类、水杨酸、乙烯、脱落酸和系统素的产生及转导方面综述了鲜切果蔬对机械伤害防御反应机制,并从伤害防御方面介绍了外源施用茉莉酸类、水杨酸和乙烯的作用机制与保鲜效果。%Fresh-cut fruit and vegetables during processing will be subjected to mechanical damage, in which the organization structure is destroyed, and it is easy to become browning and be infected by microbial, as well as the aging and corruption of the organization of fruits and vegetables are accelerated. Mechanical noxious stimulate the production, operation, perception, acceptance and transduction of signaling molecules, to activate the injury-induced defense gene expression, and then induced fresh-cut fruits and vegetables to produce the overall coordination of defense response. Jasmine acid, salicylic acid, ethylene, abscisic acid and system elements signaling molecules to induce defense reactions of fruits and vegetables can reduce the effect of mechanical damage on the quality of fresh-cut fruits and vegetables, and can effectively inhibit microbial infection of injured area and the organization enzymatic browning of fruit and vegetable,whichimprove storage quality of fruits and vegetables. This paper summarized the defensive responds of mechanical wounding and

  20. Effect of water deficit stress on yield, physiological and biochemical parameters of two Iranian cantaloupe accessions

    Directory of Open Access Journals (Sweden)

    Hadi Lotfi

    2016-06-01

    Full Text Available Water deficit stress is one of the most important environmental factors limitting plant growth and crop production. In order to evaluate the tolerance of two Iranian melons to water deficit stress, an experiment in research filed of University of Zanjan was conducted. Treatments consisted of three Irrigation levels, starting irrigation at (100, 66 and 33 % Crop Evapotranspiration and two accessions of Iranian cantaloupes (Tile-Zard and Tile-Sabz. In this experiment, total chlorophyll content, carotenoids, proline content, leaf relative water content (RWC, ascorbic acid, peroxidase and catalase activity, yield and water use efficiency (WUE were evaluated. The results indicated that water deficit stress significantly increased proline content, peroxidase and catalase activity and WUE, but decreased RWC, yield and total chlorophyll content. The highest increase in proline content (34.8 %, catalase (18 % and proxidase (42.3 % activity and reduction in yield (61.6 % and RWC (8 % was obtained in 33 % ETc Irrigation. There has been significant difference between accesesions in relation to RWC, proline, total chlorophyll and peroxidase and catalase activity. The highest value of yield and WUE was observed in 'Tile-Zard'. According to the interaction results, both accessions, 'Tile-Sabz' and 'Tile-Zard' with 63.6 % and 59.7 % Reduction in fruit yield under deficit water stress, are.

  1. A SURVEY OF SIZES AND WEIGHTS OF BEMISIA TABACI(HOMOPTERA: ALEYRODIDAE)B BIOTYPE LIFE STAGES FROM FIELD GROWN COTTON AND CANTALOUPES

    Institute of Scientific and Technical Information of China (English)

    Chang-chiChu; JamesS.Buckner; KamilKarut; ThomasP.Freeman; DennisR.Nelson; ThomasJ.Henneberryl

    2003-01-01

    Size and weight measurements were made for all the life stages of Bemisia tabaci (Gennadius) B biotype from field grown cotton ( Gossypium hirsutum L. ) and cantaloupe ( Cucumis melo L., var. cantalupensis )in Phoenix, AZ and Fargo, ND, USA in 2000 and 2001. Nymphal volumes were derived from the measurements.The average nymphal volume increase for settled 1 st to the late 4th instar was exponential. The greatest increase in body volume occurred during development from the 3rd to early 4th instar. Nymphs on cotton leaves were wider,but not longer compared with those on cantaloupe. Ventral and dorsal depth ratios of nymphal bodies from 1st tolate 4th instars from cantaloupe leaves were significantly greater compared with those from cotton leaves. During nymphal development from 1st to 4th instar, the average (from the two host species) ventral body half volume in-creased by nearly 51 times compared with an increase of 28 times for the dorsal body half volume. Adult female and male average lengths, from heads to wing tips, were 1 126 μm and 953 μm, respectively. Average adult fe-male and male weights were 39 and 17 μg, respectively. Average widths, lengths, and weights of eggs from cottonand cantaloupe were, 99 μm, 197 μm, and 0.8 μg, respectively. Average widths, lengths, and weights for exu-viae of non-parasitized nymphs from both cotton and cantaloupe were 492 μm, 673 μm, and 1.20 μg, respective-ly; and widths, lengths, and weights of parasitized nymph exuviae were 452 μm, 665 μm, and 3.62 μg, respec-tively. Both exuviae from non-parasitized and parasitized nymphs from cotton leaves were wider, longer, and heavier than those from cantaloupe leaves.

  2. Qualidade do melão cantaloupe cv. Hy-Mark minimamente processado e armazenado sob refrigeração Quality of cantaloupe melon cv. Hy-Mark minimally processed and refrigerated

    Directory of Open Access Journals (Sweden)

    Raimundo Wilane de Figueiredo

    2007-03-01

    Full Text Available A maioria das pesquisas em melão minimamente processado é concentrada no tipo 'cantaloupe', devido à sua importância no mercado internacional. O objetivo deste trabalho foi avaliar a qualidade do melão cantaloupe cv. Hy-Mark minimamente processado. Os frutos foram lavados e sanitizados, sendo em seguida cortados na forma de cubos, imersos em solução de CaCl2, acondicionados em embalagens flexíveis PET (tereftalato de polietileno e armazenados a 4ºC por 9 dias. O delineamento foi conduzido inteiramente casualizado, com três repetições. A intervalos de três dias, amostras foram coletadas e analisadas quanto a coliformes totais e fecais, e contagem de bactérias aeróbias mesófilas e bolores e leveduras, pH, sólidos solúveis totais, acidez, vitamina C, açúcares redutores totais, atividade de água, firmeza e análise sensorial através do atributo de aceitação global. O melão minimamente processado apresentou boa estabilidade física, físico-química, microbiológica e sensorial, estimando-se em 9 dias a vida útil deste produto a 4ºC.Most of the research into minimally processed melon is focused on cantaloupe melon, due to its importance in the international market. The objective of this work was to evaluate the quality of cantaloupe melon cv. Hy-Mark, minimally processed and refrigerated. Fruits were washed, sanitized, cut and imbedded in a calcium chloride solution and packed in PET and stored at 4ºC during 9 days. At three-day intervals samples were collected and analyzed for total and fecal coliforms, counting of aerobic mesophilic bacterias, molds and yeast, SS (soluble solids, TTA (total titrable acidity, firmness, pH, TRS (total reducing sugar, Aw, vitamin C, color and acceptability. The minimally processed melon showed good overall physical, pyisico-chemical, microbiological and sensorial stability during the storage period.

  3. Exogenous γ-Aminobutyric Acid Improves the Structure and Function of Photosystem II in Muskmelon Seedlings Exposed to Salinity-Alkalinity Stress

    Science.gov (United States)

    Xu, Weinan; Zhen, Ai; Zhang, Liang; Hu, Xiaohui

    2016-01-01

    Gamma-aminobutyric acid (GABA) is important in plant responses to environmental stresses. We wished to clarify the role of GABA in maintenance of photosynthesis in muskmelon seedlings (Cucumis melo L., cv. Yipintianxia) during saline-alkaline stress. To this end, we assessed the effect of GABA on the structure and function of the photosynthetic apparatus in muskmelon seedlings grown under saline-alkaline stress. These stresses in combination reduced net photosynthetic rate, gas-exchange, and inhibited photosystem II (PSII) electron transport as measured by the JIP-test. They also reduced the activity of chloroplast ATPases and disrupted the internal lamellar system of the thylakoids. Exogenous GABA alleviated the stress-induced reduction of net photosynthesis, the activity of chloroplast ATPases, and overcame some of the damaging effects of stress on the chloroplast structure. Based on interpretation of the JIP-test, we conclude that exogenous GABA alleviated stress-related damage on the acceptor side of PSII. It also restored energy distribution, the reaction center status, and enhanced the ability of PSII to repair reaction centers in stressed seedlings. GABA may play a crucial role in protecting the chloroplast structure and function of PSII against the deleterious effects of salinity-alkalinity stress. PMID:27764179

  4. Development of an organic integrated pest management (ipm module against insect-pests of muskmelon in arid region of Rajasthan, India

    Directory of Open Access Journals (Sweden)

    Shravan M Haldhar

    2014-02-01

    Full Text Available Four different muskmelon production systems (two conventional, one conventional IPM, and one organic IPM were compared in field experiments at the Central Institute for Arid Horticulture, Bikaner for two years. The organic IPM system proved to be the most effective and economical approach (B: C ratio 8.80:1 against melon aphid (Aphis gossypii, leaf eating caterpillar (Diaphania indica, hadda beetle (Epilachna vigintiopunctata and cucurbit fruit fly (Bactrocera cucurbitae in which the lowest incidence was recorded as compared to other modules. The organic IPM module-III comprised of growing resistant genotype (RM-50, spray of neem oil at 20 DAS, installation of pheromone trap (10/ hectare at 42 DAS, spray of tumba fruit extract (TFE 5% at 50 DAS and spray of spinosad 46 SC at 60 DAS was the most effective. The conventional I (farmer’s practices was the second most effective system against major pests during both years. The benefit-cost ratio of the tested muskmelon production systems in the control of insect-pests decreased in the following order: module-III (B: C ratio 8.80:1> module-I (B: C ratio 7.74:1> module-IV (B: C ratio 6.60:1> module-II (B: C ratio 3.56:1.

  5. Evaluation of different oxygen, carbon dioxide and nitrogen combinations employed to extend the shelf life of fresh-cut collard greens Avaliação de diferentes combinações de oxigênio, gás carbônico e nitrogênio utilizadas no aumento de vida de prateleira de couve minimamente processada

    Directory of Open Access Journals (Sweden)

    Celso L. Moretti

    2003-12-01

    Full Text Available Collard greens (Brassica oleracea var. acephala "Manteiga" were harvested in commercial fields in Brasilia, Brazil, aiming to evaluate different oxygen, carbon dioxide and nitrogen combinations to extend the shelf life of the fresh-cut product. After harvest, leaves were taken to the postharvest laboratory, selected for external blemishes and minimally processed (3 mm thick inside a cold room (13±2°C. After processing, fresh-cut collard greens were stored under two controlled atmosphere (CA conditions (3% O2, 4% CO2; 5% O2, 5% CO2/balance N2, and normal air (control, at 5°C (95±2% RH, for six days. Daily, minimally processed collard greens were evaluated for total vitamin C, total chlorophyll, total soluble solids content, and titratable acidity. Total vitamin C content decreased for all treatments during the storage period. Storage under CA conditions delayed total vitamin C degradation for both atmospheres studied. At the end of the storage period, fresh-cut collard greens stored under 3% O2, 4% CO2 showed around 25% and 56% more vitamin C than the material stored under 5% O2, 5% CO2 and control, respectively. Total chlorophyll content decreased during the storage period. At the end of the experiment, fresh-cut collard greens stored under 3% O2, 4% CO2 showed 24% and 45% more total chlorophyll than the product stored under 5% O2, 5% CO2 and control, respectively. CA storage delayed organic acid degradation. On the sixth day, fresh-cut collard greens stored under 3% O2, 4% CO2 presented around 44% more organic acids than control. Total soluble solids content were not significantly affected.Folhas de couve (Brassica oleracea var. acephala "Manteiga" foram obtidas em campos de produção comercial em Brasília, DF, com o objetivo de avaliar diferentes combinações de oxigênio, dióxido de carbono e nitrogênio para estender a vida de prateleira do produto minimamente processado. Após colhidas, as folhas foram levadas ao laboratório de p

  6. CRESCIMENTO E MARCHA DE ABSORC?O DE NUTRIENTES DO MEL?O CANTALOUPE TIPO "HARPER" FERTIRRIGADO COM DOSES DE N E K

    National Research Council Canada - National Science Library

    Ana Paula Alves Barreto Damasceno; José Francismar de Medeiros; Damiana Cleuma de Medeiros; Isabel Giovanna Costa e Melo; Daniel da Costa Dantas

    2012-01-01

    ... de absorção e o acúmulo de nutrientes pelo melão cantaloupe tipo "Harper" visando à recomendação de adubação para aplicação via fertirrigação. O experimento foi instalado em blocos casualizados, com duas...

  7. Avaliação de índices de firmeza para abacaxi minimamente processado em fatias tratadas com soluções de sais de cálcio Firmness indexes evaluation for fresh-cut sliced pineapple treated with calcium salts solutions

    Directory of Open Access Journals (Sweden)

    Marisa de P. Eduardo

    2008-03-01

    Full Text Available Produtos minimamente processados estão prontos para o consumo imediato e devem apresentar qualidade sensorial semelhante à do produto fresco. Embora a maioria dos estudos seja com hortaliças, constata-se o grande potencial de comercialização de frutas minimamente processadas, principalmente aquelas que oferecem alguma dificuldade para a comercialização ou até mesmo para o preparo, sendo o abacaxi um ótimo exemplo disso. O objetivo deste trabalho foi avaliar o efeito de diferentes sais de cálcio (cloreto, sulfato e lactato, nas concentrações de 1% e 3%, utilizando-se de medidas de pH , sólidos solúveis totais e da firmeza, em fatias de abacaxi minimamente processadas. Dois tipos de ponteiras de penetração (cilíndrica e anel vazador e três índices de firmeza foram utilizados para mensurar a textura, visando a identificar o melhor índice. Os resultados mostraram que os tratamentos com sulfato de cálcio 3% mantiveram o índice de firmeza das fatias em até 44,45% superior ao da testemunha. Os índices da ponteira cilíndrica, apesar de apresentarem variabilidade semelhante aos da ponteira de anel vazador, apontaram número maior de diferenças entre a testemunha e os tratamentos.Fresh-cut sliced fruits and vegetables are ready to eat immediately and their sensorial characteristics should be similar to fresh product. Although most of the studies in this area are focused on vegetables, there is a great market potential for fresh-cut sliced fruits, mainly for those which exhibit some commercialization or preparation difficulties such as pineapple. The objective of this work was to evaluate the effect of 1% and 3% concentrations of calcium salts (chloride, sulphate and lactate on pH, total soluble solids and firmness values of minimally processed pineapple slices. Two types of indenters and three firmness indexes were investigated aiming to identify the best index. Results showed that calcium sulphate 3% kept average firmness index

  8. Avaliação da qualidade do caldo extraído de toletes de cana-de-açúcar minimamente processada, armazenados sob diferentes temperaturas Evaluation of the quality of the juice extracted of pieces of fresh cut sugar cane stored under different temperatures

    Directory of Open Access Journals (Sweden)

    Silvana Rodrigues Rabelo de Andrade

    2008-12-01

    Full Text Available O presente trabalho visou avaliar a qualidade físico-química e microbiológica do caldo extraído de toletes de cana-de-açúcar minimamente processada, armazenados sob três temperaturas. Colmos de cana-de-açúcar foram minimamente processados na forma de toletes com 60 cm de comprimento, higienizados e acondicionados em embalagens de polietileno de baixa densidade. Cada embalagem acondicionou 12 toletes de cana-de-açúcar devidamente higienizados. Em seguida, procedeu-se o armazenamento das embalagens sob três temperaturas: ambiente (22 a 25 °C, utilizada como controle, refrigeração (4 °C e congelamento (-20 °C. Foram avaliadas a qualidade físico-química do caldo e a sua composição microbiológica, em intervalos de 6 dias, durante 24 dias de armazenamento. O caldo extraído dos toletes armazenados sob congelamento apresentou boa qualidade físico-química e microbiológica durante todo o período avaliado. Por outro lado, o caldo extraído dos toletes armazenados sob refrigeração e o controle apresentaram elevadas alterações microbiológicas, limitando o período de conservação dos toletes até 12 e 6 dias, respectivamente, o que permitiu concluir que o tratamento mais eficiente para a preservação da qualidade do caldo foi o congelamento da cana-de-açúcar minimamente processada.The present work aimed at evaluating the microbiological and physicochemical quality of fresh cut sugar cane juice. Sugar cane stalks were cut in pieces of 60 cm of length, sanitized, and conditioned in polyethylene packaging of low density. Each package conditioned 12 pieces of sanitized sugar can. After that, they were stored at three different temperatures: room temperature (22-25 °C, used as control, refrigeration (4 °C, and freezing (-20 °C. The microbiological and physicochemical quality of the juice was evaluated every 6 days of storage for 24 days. The sugar cane juice stored under freezing temperatures presented good quality for all

  9. 响应曲面法优化酸性电解水对鲜切苹果杀菌效果的影响%Response Surface Methodology for Optimization of Sterilization Effect on Fresh-Cut Apple Treated with Acidic Electrolyzed Water

    Institute of Scientific and Technical Information of China (English)

    于晓霞; 李燕; 王婷婷; 宋星

    2015-01-01

    以微生物减菌率为评价指标,在单因素试验的基础上,采用中心组合设计法,研究NaCl质量浓度、处理温度、处理时间,以及料液比对接种金黄色葡萄球菌、大肠杆菌、沙门氏菌和单增细胞李斯特菌的鲜切苹果杀菌效果的影响。响应面分析结果表明,鲜切苹果减菌工艺最优条件为:NaCl质量浓度4.5 g/L,处理温度25℃,处理时间6.45 min,液料比6∶1(mL/g),在此条件下经处理后细菌总数由1.14×105 CFU/g降为9.3×103 CFU/g,减菌率可达91.84%。同时,该处理对鲜切苹果的pH值和可溶性固形物影响不大,且能较好地抑制维生素C的降解及其表面的褐变。%The sterilization effect of acidic electrolyzed water on fresh- cut apple against Staphylococcus aureus, Escherichia coli, salmonella and Listeria monocytogenes cells was studied by response surface methodology and a central composite design with one-factor-at-a-time. Studied variables of NaCl concentration, time, temperature and solid-liquid ratio were selected for the determination of optimal conditions with bactericidal ability evaluated. The optimal conditions were found to be as follows: 6:1 liquid-solid ratio (mL/g) and 4.5 g/L NaCl treated under 25℃for 6.45 min. Under these conditions, the total bacteria count was reduced from 1.14 × 105 CFU/g to 9.3 × 103 CFU/g and the reduction rate of bacteria was up to 91.84%. Moreover, this treatment slightly affected the pH value and the soluble solid contents of fresh-cut apples, while effectively inhibited the degradation of vitamin c and provided surface browning control.

  10. 不同肥料施用对嫁接薄皮甜瓜生长、产量及品质的影响%Effect of Different Fertilizer Application on Growth, Yield and Quality of Graft Pellicular Muskmelon

    Institute of Scientific and Technical Information of China (English)

    赵依杰; 吴宇芬; 陈贻钊; 林航; 陈晟; 张伟光

    2012-01-01

    采用控释肥、有机肥、有机无机复混肥和复合肥等4种肥料作为基肥,按株施肥料价格相等设计,以施用复合肥为对照,研究不同肥料施用对嫁接薄皮甜瓜生长、产量及品质的影响.结果表明:施用有机无机复混肥,在定植35 d后接穗主茎粗与第1子蔓长度均显著大于其他各处理,但薄皮甜瓜的产量显著下降,品质降低.施用控释肥薄皮甜瓜单果质量比对照提高3.1%,产量增加7.3%,可溶性固形物含量提高1.5%;施用有机肥,薄皮甜瓜的品质最优,但产量比对照下降了17.7%.综合评价认为,控释肥是嫁接薄皮甜瓜较理想的肥料.%In this paper, the effect of different fertilizer application on growth, yield and quality of graft pellicular muskmelon ( Cucumis melo L. var. makuwa Makino ) was studied by adopting 4 kinds of fertilizer including controlled—release fertilizers, organic fertilizer, organic—inorganic compound fertilizers and complex fertilizer as basic fertilizer. This research was designed by equal fertilizer price which was invested in every muskmelon plant, taking complex fertilizer application as contrast. The results showed that 35 days after planting, by applying organic-inorganic compound fertilizers the thickness of scion main stem and the length of the first tendril were all significantly larger than that by other treatments. But the yield and quality of pellicular muskmelon were remarkably dropped down. By applying controlled-release fertilizers, the weight of single fruit of pellicular muskmelon improved 3.1%, its yield increased 7.3%, and the content of soluble solid matter rose 1.5%. The quality of pellicular muskmelon was the best, because of applying organic fertilizer. But the yield decreased 17.7%. The integrated review believes that controlled-release fertilizers are ideal basic fertilizer for graft pellicular muskmelon.

  11. The use of gamma radiation aiming to post harvest conservation of Cantaloupe melon (Cucumis melo L. var. Cantaloupensis);Utilizacao de radiacao gama em meloes cantaloupe (Cucumis melo L. var. Cantaloupensis) como tecnica de conservacao pos-colheita

    Energy Technology Data Exchange (ETDEWEB)

    Siqueira, Alessandra Aparecida Zilio Cozzo de

    2007-07-01

    Although Brazilian fruit culture has been growing in the international market, the fruit quality and the post harvest technology have not been improved properly. In Brazil, fruit nutritional factors are very important because of their potential to provide suitable nutrients for a significant part of the Country population. Some post harvest technologies, such as ionizing radiation, can keep the physical, chemical, nutritional and sensorial characteristics of the natural fruit, improving the quality of the fruits in the market. This work evaluated the effects of Cobalt 60 irradiation in Cantaloupe melon, aiming the post harvest conservation during 7 days of storage, at a temperature ranging from 20 to 22 deg C. The doses of irradiation were set to 0, 150, 300, 450, 600, 750 and 900 Gy, based on the multiple of 150 Gy quarantine dose, aiming to establish the lowest, the highest and the ideal doses. Afterwards, physical, chemical and nutritional characteristics of irradiated fruit were checked and, finally, the sensorial characteristics through acceptability test. Results indicated that the doses higher than 450 Gy affected firmness, pulp yield and color (L and a{sup *}) parameters. Nevertheless, analyzing physical, chemical and nutritional parameters, doses of 450 and 900 Gy kept pH, tetrable acidity, soluble solids, color (a{sup *} and b{sup *}), chlorophyll and carotenoids, phenolic compounds, respiratory rate and ethylene level. The storage period was the most important factor that affected the quality of the fruit, despite of the radiation doses. Based on the acceptability test, the best evaluated fruits were from the treatments of 450 and 900 Gy. This work allowed to conclude that fruit radiation is an appropriate technology for Cantaloupe melon post harvest conservation, but it is necessary to be used in combination with other technologies, especially to fungi control. (author)

  12. 优质抗白粉病网纹甜瓜新品系的选育及利用%Breeding and Using of New Muskmelon Strains Which is Good in Quality and Powdery Mildew Resistant

    Institute of Scientific and Technical Information of China (English)

    李秀秀; 段爱民; 吕敬刚; 李长缨; 焦定量; 张艳宁; 加藤正弘

    2001-01-01

    Powdery mildew resistant Hami melon type variety was used tocross with muskmelon variety,then through inbreeding successively,seperating and selecting,according to the results of powdery mildew development naturally in field and artificial inoculation in seedling stage,three muskmelon strains which is powdery mildew resistant were obtained.The characteristics of their fruits were surveyed and the hybrid combinations by them were made.Three strains all show good netted veins,sick pulp and high sugar content.This will supply parent materials for breeding of new muskmelon hybrid.%利用抗病的哈密瓜类型材料与网纹类型材料杂交,结合田间自然发病和苗期人工接种抗性鉴定,通过连续自交分离选择,获得3个稳定的抗白粉病的网纹类型品系材料。经果实性状调查和杂交组合配制,3个品系均表现出网纹形成良好、果肉厚,折光糖含量高等特点,为网纹甜瓜新品种选育提供了亲本材料。

  13. Pathogen biofilm formation on cantaloupe surface and its impact on the antibacterial effect of lauroyl arginate ethyl.

    Science.gov (United States)

    Fu, Yezhi; Deering, Amanda J; Bhunia, Arun K; Yao, Yuan

    2017-06-01

    Pathogen biofilm at fruit surface may pose a particular risk to food safety. In this study, the biofilms of Listeria monocytogenes V7 and Salmonella enterica serovar Typhimurium ATCC 13311 on cantaloupe fruit surface were visualized, and the resistance of biofilms against lauroyl arginate ethyl (LAE, an antibacterial compound) was evaluated. Each bacterium was inoculated on isolated cantaloupe rind surfaces at 10(5)-10(6) CFU/cm(2) and after incubation for 2, 12, 24, and 48 h, the surfaces were imaged using cryo-scanning electron microscopy (Cryo-SEM). The images showed that both pathogens formed biofilms on rind surfaces, with S. Typhimurium forming biofilm in 12 h and L. monocytogenes cells starting to aggregate in 2 h. For the inoculated rind surfaces treated with LAE, the cell counts were affected by both the incubation time and LAE concentration. For rind surface with 2 h incubation of S. Typhimurium, 400 and 800 μg/mL LAE was able to achieve >2.00 log reduction; however, 12 h incubation required 1600 and 2000 μg/mL LAE for >2.00 log reduction. In contrast, even the highest LAE concentration (2000 μg/mL) was unable to cause 1.00 log reduction for L. monocytogenes regardless the incubation time applied. The results showed that the biofilms of both bacteria substantially reduced LAE efficacy, and that the biofilm of L. monocytogenes was more resistant than that of S. Typhimurium. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Bioremediation of soil contaminated with spent and fresh cutting ...

    African Journals Online (AJOL)

    OLAYONWAOLUWOLE JOHN

    2013-10-16

    Oct 16, 2013 ... hydrocarbons has detrimental effects on ecosystems. As such contaminants ... cuttings containing Polyaromatic Hydrocarbons (PAH's) ... water soluble cutting fluid of varying concentrations (0, 10, 20 and. 30%). A mud ...

  15. Bioremediation of soil contaminated with spent and fresh cutting ...

    African Journals Online (AJOL)

    As such contaminants constitute risk to human health; they can enter the food ... White rot fungus, Pleurotus pulmonarius was investigated in this pilot study for its ... Copper, manganese and nickel decreased significantly by 35.3, 25.0 and ...

  16. Importance of Seed Quality for the Fresh-cut Chain

    DEFF Research Database (Denmark)

    Deleuran, Lise Christina; Olesen, Merete Halkjær; Shetty, Nisha

    2011-01-01

    Seed is the most fundamental input in vegetable production on, which the effectiveness of other inputs and outputs depends. If the seed is of poor quality, the use of other inputs is less successful and will occasionally be irrelevant. A definition of seed quality will depend upon the use for, wh...

  17. Comparative Study of Cold Storage Effects and Organic Acid Component Contents in Fresh Cut Seeds of Different Pomegranate Varieties%鲜切石榴籽粒冷藏效果及有机酸组分含量比较研究

    Institute of Scientific and Technical Information of China (English)

    杨雪梅; 尹燕雷; 冯立娟; 武冲; 王菲

    2016-01-01

    The fresh cut seeds of pomegranate varieties Taishansanbaitian,Mudan and Sanbaisuan were used as materials.The seeds were sterilized under the UV -lamp for 15 minutes,and then stored at (4 ± 0.5)℃ for 18 days.The freshness -keeping effect,organic acid component contents and antioxidant activity were compared among the 3 varieties.The results showed that the fresh cut seeds of pomegranate varieties Mu-dan and Sanbaisuan owned lower weight loss,rotting rate and relative electrolytic leakage,significantly lower oxalic acid content,significantly higher DPPH free radical scavenging rate and citric acid content,and more stable titratable acid and total soluble solid contents compared with Taishansanbaitian during the cold storage. The main organic acids of the 3 pomegranate varieties all were citric acid,malic acid,oxalic acid and tartaric acid.The malic acid content in pomegranate variety Mudan was significantly lower than that in Sanbaisuan and Taishansanbaitian,while the tartaric acid contents of 3 pomegranate varieties were not significantly different during the storage process.The freshness -keeping effect of the 2 sour pomegranate varieties Mudan and San-baisuan were superior to sweet pomegranate variety Taishansanbaitian.The pomegranate variety Mudan had the most stable organic acid component contents and the best freshness -keeping effect.%以‘泰山三白甜’、‘三白酸’和‘牡丹’石榴成熟期的果实为试材,籽粒经紫外杀菌15 min 后装入保鲜袋于(4±0.5)℃冷藏保鲜18 d,期间比较3个品种籽粒的保鲜品质、有机酸组分含量变化及抗氧化活性。结果表明:2个酸石榴品种籽粒冷藏过程中的失重率、腐烂率、相对电导率均低于甜石榴品种‘泰山三白甜’;而 DPPH 自由基清除率均显著高于‘泰山三白甜’;2个酸石榴品种中可滴定酸和总可溶性固形物含量在整个冷藏期内较稳定,均比‘泰山三白甜’变化幅度小;3个

  18. Qualidade de produtos minimamente processados e comercializados em gôndolas de supermercados nas cidades de Lavras - MG, Brasília - DF e São Paulo - SP Quality of fresh-cut produce commercialized on supermarket shelves in the cities of Lavras-MG, Brasília-DF, and São Paulo-SP

    Directory of Open Access Journals (Sweden)

    Nélio Ranieli Ferreira de Paula

    2009-02-01

    Full Text Available A produção de frutos e hortaliças minimamente processados mostrou crescimento relevante nos últimos anos, em razão de acentuadas mudanças no estilo de vida do consumidor, como redução das famílias, busca de conveniência e conscientização da necessidade de uma dieta alimentar saudável e que atenda às exigências de segurança alimentar. Objetivou-se, neste trabalho, caracterizar a qualidade química, físico-química e microbiológica dos produtos minimamente processados, coletados em gôndolas de supermercados em Lavras - MG, Brasília - DF e São Paulo - SP para orientar seus fornecedores e consumidores quanto à necessidade de maior controle de qualidade, devido aos riscos de contaminação de matérias-primas por microrganismos patogênicos e deteriorantes. 144 amostras foram coletadas e submetidas às determinações de pH, acidez titulável e sólidos solúveis e avaliações microbiológicas (coliformes a 45ºC, Escherichia coli e Salmonella sp.. Os resultados mostraram variações significativas nos valores de pH e foi observada diminuição de acidez e sólidos solúveis, durante o armazenamento. Foi detectada contaminação por coliformes a 45ºC sendo que, em 50% dessa presença, houve isolamentos de Escherichia coli, evidenciando contaminação oriunda de matéria-prima inadequadamente higienizada ou por sua presença nos manipuladores. Contudo, não foi detectada contaminação por Salmonella sp.. Os resultados obtidos indicaram a necessidade de implementação de Boas Práticas de Fabricação (BPF, no controle de qualidade desses produtos.The production of fresh-cut fruits and vegetables has shown an outstanding growth in the latest years, due to the remarkable changes in the consumers' life style, such as family reduction, search for convenience and increased awareness of a wholesome food diet which meets the requirements of food safety. The aim of this work was to characterize the physicochemical and microbiological

  19. Caracterização química e física de batatas 'Ágata' minimamente processadas, embaladas sob diferentes atmosferas modificadas ativas Chemical and physical characterization of fresh-cut 'Ágata' potatoes packed under different active modified atmospheres

    Directory of Open Access Journals (Sweden)

    Lívia Lacerda Oliveira Pineli

    2005-10-01

    Full Text Available O objetivo deste trabalho foi avaliar as alterações químicas e físicas em batatas 'Ágata' minimamente processadas, embaladas sob diferentes atmosferas, durante o armazenamento refrigerado. Batatas 'Ágata' foram minimamente processadas como minibatatas e embaladas em filmes de náilon multicamadas. Os tratamentos aplicados no momento da embalagem foram o vácuo parcial e as misturas 10%CO2, 2%O2, 88%N2 ou 5%CO2, 5%O2, 90%N2. Em seguida, foram armazenadas a 5ºC. A cada três dias, amostras foram avaliadas quanto ao índice de escurecimento, atividade da polifenoloxidase e peroxidase, firmeza, sólidos solúveis totais e acidez titulável. O armazenamento sob vácuo parcial foi o mais eficaz no controle do escurecimento, da minimização da atividade da polifenoloxidase e da peroxidase, prevenindo alterações nos teores de sólidos solúveis totais, redução da firmeza, encharcamento da embalagem e maior acidez titulável. Os demais tratamentos apresentaram rápido desenvolvimento do escurecimento, aumento de firmeza em decorrência de ressecamento dos tubérculos, elevação nos sólidos solúveis totais e menor desenvolvimento da acidez em comparação ao tratamento sob vácuo parcial. A utilização de vácuo parcial foi a mais recomendada para a manutenção da qualidade das minibatatas. Todavia, outros tratamentos que busquem a manutenção da firmeza e frescor, sem o desenvolvimento de off-flavors e sem escurecimento, devem ser avaliados.The objective of this work was to evaluate chemical and physical characteristics of fresh-cut 'Ágata' potatoes packed under different active modified atmospheres, during refrigerated storage. 'Ágata' potatoes were minimally processed as baby potatoes and packed in nylon multilayer films. The treatments applied were partial vacuum, and atmospheres with 10%CO2, 2%O2, 88%N2 and 5%CO2, 5%O2, 90%N2. After that, they were stored at 5ºC. Every three days, tubers were evaluated for browning index

  20. Volatile profile and physical, chemical, and biochemical changes in fresh cut watermelon during storage Perfil volátil e alterações físicas, químicas e bioquímicas na melancia minimamente processada durante o armazenamento

    Directory of Open Access Journals (Sweden)

    Andréa Luiza Ramos Pereira Xisto

    2012-03-01

    Full Text Available Existing data about the aroma of fresh-cut watermelon and the metabolic changes that occur with minimal processing are scarce. Given the close relationship that exists between aroma, texture, and quality characteristics, it is necessary to investigate the changes in the volatile profile and texture of watermelon, a fruit extensively sold in supermarket chains throughout Brazil. The objective of this work was to analyze the volatile profile using solid phase microextraction (SPME as well as texture changes in fresh-cut watermelon stored at 5 °C for ten days. Chromatography associated with sensory analysis (sniffing led us to conclude that 9-carbon (C9 alcohols and aldehydes are the major responsible for the flavor and aroma of minimally processed watermelon stored at 5 ± 1 °C/90 ± 5% RH for ten days, and also that the aroma diminishes in intensity with storage, but it does not affect the final quality of the product. It was noted that the amount of drained liquid, soluble pectin, and weight loss increased during storage concurrently with a reduction in firmness and a structural breakdown of the cells. Pectin methyl esterase activity remained constant and polygalacturonase activity was not detected.Existe pouca informação a respeito do aroma de melancia minimamente processada e das alterações metabólicas que ocorrem com o processamento mínimo. Sabendo-se que há estreita relação entre aroma característico, textura e qualidade torna-se necessário o conhecimento a respeito das alterações do perfil volátil e textura deste produto, que é intensamente comercializado nas redes de supermercados do Brasil. Diante disso, o objetivo deste trabalho foi analisar o perfil volátil utilizando a técnica de microextração em fase sólida (SPME e as modificações relacionadas à textura de melancia minimamente processada armazenada a 5 °C, por dez dias. A cromatografia associada com análise sensorial ('sniffing' permitiu concluir que os

  1. Hydroponic growth of crops in presence of /sup 14/C-benzo(a)pyrene. [/sup 14/C tracer study in beans, cantaloupes, and cotton plants

    Energy Technology Data Exchange (ETDEWEB)

    Blum, S.C.; Swarbrick, R.E.

    1975-09-01

    An attempt was made to evaluate the fate of a polynuclear aromatic hydrocarbon in the food chain under severe and exaggerated experimental conditions. Green beans, cantaloupes, and cotton were grown hydroponically in nutrient-containing aqueous solutions saturated with carbon-14 labeled benzo(a)pyrene, a known carcinogen. The plants were selected because of different growing times involved: 6, 12, and 22 weeks for green beans, cantaloupes, and cotton, respectively, as well as the great differences in these plant types. Results indicate that the translocation or migration of polynuclear aromatic hydrocarbons during the growth cycle of crops is not a reasonable expectation. Any such contamination found in crops would, therefore, require some other explanation.

  2. Influência de sanificantes nas características microbiológicas, físicas e físico-químicas de cebola (Allium cepa L. minimamente processada Effect of sanitizers on the microbial, physical and physical-chemical characteristics of fresh-cut onions (Allium cepa L

    Directory of Open Access Journals (Sweden)

    Karla Michalsky Carvalho Beerli

    2004-02-01

    âmetros analisados, a qualidade da cebola se manteve adequada para o consumo em todos os tratamentos até o sétimo dia após o processamento, incluindo o tratamento-controle (sem sanificante.The goal of this work was to evaluate the effect of hydrogen peroxide (H2O2 and sodium dichloroisocianurate (NaDCC sanitizers on the shelf-life of fresh-cut onion, based on the microbial development and physical and physical-chemical characteristics. The onions were washed, peeled and sliced. The following treatments were tested using three randomized blocks: H2O2 (2%, H2O2 (4%, H2O2 (6%, NaDCC (50ppm and NaDCC (100ppm. The slices were packed and stored at 4ºC for 7 days, after sanitation. One package for treatment was used daily and the following variables were evaluated: standard counting of mesophile aerobic microorganisms, total counting of psychrotrophs aerobic microorganisms, moulds and yeasts, total coliforms at 35ºC and 45ºC, total soluble solids (TSS, pH, titratable acidity (TA, firmness and mass loss. Lower counting of mesophile aerobic were found in slices treated with H2O2; all treatments, but control, were effective in decreasing psychrotroph aerobic and total coliforms at 35ºC; coliforms 45ºC were not found in slices of any treatment; only H2O2 (4% and H2O2 (6% treatments decreased the values of moulds and yeasts; the treatments did not affect the TSS and mass loss; NaDCC treatments promoted higher pH; lower TA were found in slices treated with H2O2 (4%, H2O2 (6% and NaDCC (50ppm and higher firmness were obtained in slices treated with H2O2 (4% and H2O2 (6%. From the results it is concluded that H2O2 (4 and 6% was more effective sanitizer for fresh-cut onions than NaDCC; according the analyzed parameters, the fresh-cut onion was held in proper edible conditions for 7 days after processing, including the control (without sanitizer.

  3. Surface survival and internalization of salmonella through natural cracks on developing cantaloupe fruits, alone or in the presence of the melon wilt pathogen Erwinia tracheiphila.

    Directory of Open Access Journals (Sweden)

    Dhiraj Gautam

    Full Text Available Outbreaks of foodborne illness attributed to the consumption of Salmonella-tainted cantaloupe have occurred repeatedly, but understanding of the ecology of Salmonella on cantaloupe fruit surfaces is limited. We investigated the interactions between Salmonella enterica Poona, the plant pathogenic bacterium Erwinia tracheiphila, and cantaloupe fruit. Fruit surfaces were inoculated at the natural cracking stage by spreading S. enterica and E. tracheiphila, 20 µl at 107 cfu/ml, independently or together, over a 2×2 cm rind area containing a crack. Microbial and microscopic analyses were performed at 0, 9 and 24 days post inoculation (DPI. Even at 24 DPI (fruit maturity S. enterica was detected on 14% and 40% of the fruit inoculated with S. enterica alone and the two-pathogen mixture, respectively. However, the population of S. enterica declined gradually after initial inoculation. E. tracheiphila, inoculated alone or together with Salmonella, caused watersoaked lesions on cantaloupe fruit; but we could not conclude in this study that S. enterica survival on the fruit surface was enhanced by the presence of those lesions. Of fruit inoculated with E. tracheiphila alone and sampled at 24 DPI, 61% had watersoaked lesions on the surface. In nearly half of those symptomatic fruits the watersoaking extended into the sub-rind mesocarp, and E. tracheiphila was recovered from that tissue in 50% of the symptomatic fruit. In this work, E. tracheiphila internalized through natural cracks on developing fruits. S. enterica was never detected in the fruit interior (ca. 2-3 mm below rind surface under the limited conditions of our experiments, but the possibility that it, or other human pathogens that contaminate fresh produce, might also do so should be investigated under a wider range of conditions and produce types.

  4. Surface survival and internalization of salmonella through natural cracks on developing cantaloupe fruits, alone or in the presence of the melon wilt pathogen Erwinia tracheiphila.

    Science.gov (United States)

    Gautam, Dhiraj; Dobhal, Shefali; Payton, Mark E; Fletcher, Jacqueline; Ma, Li Maria

    2014-01-01

    Outbreaks of foodborne illness attributed to the consumption of Salmonella-tainted cantaloupe have occurred repeatedly, but understanding of the ecology of Salmonella on cantaloupe fruit surfaces is limited. We investigated the interactions between Salmonella enterica Poona, the plant pathogenic bacterium Erwinia tracheiphila, and cantaloupe fruit. Fruit surfaces were inoculated at the natural cracking stage by spreading S. enterica and E. tracheiphila, 20 µl at 107 cfu/ml, independently or together, over a 2×2 cm rind area containing a crack. Microbial and microscopic analyses were performed at 0, 9 and 24 days post inoculation (DPI). Even at 24 DPI (fruit maturity) S. enterica was detected on 14% and 40% of the fruit inoculated with S. enterica alone and the two-pathogen mixture, respectively. However, the population of S. enterica declined gradually after initial inoculation. E. tracheiphila, inoculated alone or together with Salmonella, caused watersoaked lesions on cantaloupe fruit; but we could not conclude in this study that S. enterica survival on the fruit surface was enhanced by the presence of those lesions. Of fruit inoculated with E. tracheiphila alone and sampled at 24 DPI, 61% had watersoaked lesions on the surface. In nearly half of those symptomatic fruits the watersoaking extended into the sub-rind mesocarp, and E. tracheiphila was recovered from that tissue in 50% of the symptomatic fruit. In this work, E. tracheiphila internalized through natural cracks on developing fruits. S. enterica was never detected in the fruit interior (ca. 2-3 mm below rind surface) under the limited conditions of our experiments, but the possibility that it, or other human pathogens that contaminate fresh produce, might also do so should be investigated under a wider range of conditions and produce types.

  5. Carotene and novel apocarotenoid concentrations in orange-fleshed Cucumis melo melons: determinations of beta-carotene bioaccessability and bioavailability

    Science.gov (United States)

    Muskmelons, both cantaloupe (Cucumis melo Reticulatus Group) and orange-fleshed honey dew (C. melo Inodorus Group), a cross between orange-fleshed cantaloupe and green-fleshed honey dew, are excellent sources of ß-carotene. Although ß-carotene from melon is an important dietary antioxidant and precu...

  6. Genomic characterization of Listeria monocytogenes strains involved in a multistate listeriosis outbreak associated with cantaloupe in US.

    Directory of Open Access Journals (Sweden)

    Pongpan Laksanalamai

    Full Text Available A multistate listeriosis outbreak associated with cantaloupe consumption was reported in the United States in September, 2011. The outbreak investigation recorded a total of 146 invasive illnesses, 30 deaths and one miscarriage. Subtyping of the outbreak associated clinical, food and environmental isolates revealed two serotypes (1/2a and 1/2b and four pulsed-field gel electrophoresis two-enzyme pattern combinations I, II, III, and IV, including one rarely seen before this outbreak. A DNA-microarray, Listeria GeneChip®, developed by FDA from 24 Listeria monocytogenes genome sequences, was used to further characterize a representative sample of the outbreak isolates. The microarray data (in the form of present or absent calls of specific DNA sequences separated the isolates into two distinct groups as per their serotypes. The gene content of the outbreak-associated isolates was distinct from that of the previously-reported outbreak strains belonging to the same serotypes. Although the 1/2b outbreak associated isolates are closely related to each other, the 1/2a isolates could be further divided into two distinct genomic groups, one represented by pattern combination I strains and the other represented by highly similar pattern combinations III and IV strains. Gene content analysis of these groups revealed unique genomic sequences associated with these two 1/2a genovars. This work underscores the utility of multiple approaches, such as serotyping, PFGE and DNA microarray analysis to characterize the composition of complex polyclonal listeriosis outbreaks.

  7. Fatty acid composition and antioxidant activity of oils from two cultivars of Cantaloupe extracted by supercritical fluid extraction

    Energy Technology Data Exchange (ETDEWEB)

    Ismail, M.; Mariod, A.; Bagalkotkar, G.; Ling, H. S

    2010-07-01

    The effect of supercritical fluid extraction (SFE) fractionation of three oil fractions (1st, 2nd, 3rd fraction) on the fatty acid composition and antioxidant activity of oils from two cultivars of cantaloupe were investigated. Rock melon oil (RMO) and Golden Langkawi oil (GLO) were extracted using SFE and the major fatty acids for both cultivars were linoleic, oleic, palmitic, and stearic acid. The SFA decreased from 15.78 to 14.14% in RMO 1st fraction, and MUFA decreased from 18.30 to 16.56% in RMO 2nd fraction, while PUFA increased from 65.9 to 69.30% in RMO 3rd fraction. On the other hand SFA decreased from 16.35 to 13.91% in GLO 1{sup s}t fraction, and MUFA decreased from 17.50 to 15.57% in GLO 2nd fraction, while PUFA increased from 66.15 to 70.52% in GLO 3rd fraction. The different fractions of the two oils showed high antioxidant activity in reducing the oxidation of {beta}-carotene in beta-carotene bleaching assay (BCB) and the quenching of 1,1-diphenyl-2-picrylhydrazyl (DPPH). (Author) 41 refs.

  8. Agronomical and biological results of solar energy heating by the combination of the sunstock system with an outside captor on a muskmelon crop grown in polyethylene greenhouses

    Directory of Open Access Journals (Sweden)

    Vandevelde, R.

    1983-01-01

    Full Text Available Six cultivars of muskmelon (Early Dew, "68-02", "Early Chaca", "Jivaro", "Super Sprint" and "Cantor" transplanted at two differents dates were cultivated under two PE greenhouses heated by solar energy recovery and compared to a control greenhouse. The greenhouses were covered with a double shield of normal PE of 100 microns. The first greenhouse was considered as the control. The second one was equipped with a sunstock solar energy collector distribution system, consisting in a covering of 37 % of the ground surface by flat black PVC tubes, used during the day as a solar energy captor for heating the water of a basin and during the night as a radiant mulch for heating the greenhouse by emission of radiation warmth. The third greenhouse was equipped also with the same sunstock System, but connected with a supplementary outdoor collector by means of flat PE tubes corresponding to about 28 % covering of the greenhouse, and resulting in a more important energy stock, available for heating during the night. Minimum air temperature was raised by about 1, 5 and 2, 5°C respectively in the second and the third greenhouse, while the minimum soil temperature was raised with about 1 and 2°C respectively. Evolution of the maximum temperatures was more irregular and was depending also from the incident energy. Plant growth under the solar heated greenhouse was more accelerated, and resulted in an earlier fruitset, an earlier production and a higher total yield.

  9. Effects of exogenous substances on cold resistance of muskmelon seedlings%外源物质处理对网纹甜瓜幼苗抗寒性的影响

    Institute of Scientific and Technical Information of China (English)

    卢明; 邓征宇; 陈豫梅; 陈丹; 孙奇

    2012-01-01

    The cold resistance of muskmelon seedlings were studied by a procedure of using different exogenous substances to treat seedlings,undertaking cold stress,measuring the enzyme activities of POD,CAT and EC value of root exudate.The results showed that,6-BA had the most best effect on improving cold resistance of muskmelon seedlings and the secondary one was salicylic acid;daminozide,chlormequat and penicillin could improve cold resistance in some degree;CaCl2 had little difference with the control in POD,CAT activities,but had better protection effect for cell membrane,and NAA could cause the decrease of cold resistance of muskmelon seedlings.%通过不同外源物质处理甜瓜幼苗,并进行低温胁迫处理,测定不同处理后甜瓜幼苗叶片的POD、CAT酶活性和根系外渗液的EC值,研究其对甜瓜幼苗抗寒性的影响,结果表明:6-BA和水杨酸有助于提高甜瓜幼苗的抗寒性,而以6-BA效果最好,水杨酸次之;比久、矮壮素、青霉素对甜瓜幼苗抗寒性有一定的提高作用;氯化钙处理POD、CAT酶活性与对照差异不大,但对细胞膜有较好的保护效果;萘乙酸会导致甜瓜幼苗抗寒性下降。

  10. Functional method implementation of post-crop conservation of melon cantaloupe, using ionizing radiation as quality control technique in productive chain; Implantacao de metodo funcional de conservacao pos-colheita de meloes cantaloupe, utilizando as radiacoes ionizantes como tecnica de controle de qualidade na cadeia produtiva

    Energy Technology Data Exchange (ETDEWEB)

    Siqueira, Alessandra A.Z. Cozzo de; Matraia, Clarice; Walder, Julio Marcos M. [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil). Dept. de Irradiacao de Alimentos e Radioentomologia]. E-mail: aazcozzo@cena.usp.br; Spoto, Marta H.F.; Silva, Paula P.M. da; Maretti, Marina S. [Escola Superior de Agricultura Luiz de Queiroz, Piracicaba, SP (Brazil). Dept. de Agroindustria, Alimentos e Nutricao

    2005-07-01

    The Brazilian fruit culture is an alternative to minimize the lack-of-food problem using management and post harvest appropriate techniques. Gamma radiation technology is a possible technique used for food, enlarging its shelf-life, eliminating pathogenic microorganisms and in the quarantine treatment. The irradiation with seven doses (150,300,450,600,750 and 900 Gy) was used in Cantaloupe melon (Cucumis melon var. Cantaloupensis) aiming to establish the minimum, maximum and ideal doses, according to Brazilian laws, analyzing weight, color, firmness, pulp and juice quantity and sensory aspects, using the Difference Control Test. The results indicate that storage influenced significantly the weight, color and pulp quantity parameters. Doses higher than 450 Gy however influenced the firmness, juice quantity and sensory aspects characteristics. These results are indicating that the minimum dose was 150 Gy, the maximum dose was 900 Gy and the ideal dose for the quarantine treatment and to increase shelf-life of the Cantaloupe melon was 450 Gy. The data obtained allowed us to conclude that the ionizing radiation can increase the shelf-life of the Cantaloupe melon using doses up to 450 Gy making it proper to exportation. (author)

  11. Influência da posição e formato de corte na preferência sensorial de abacaxi 'Pérola' minimamente processado Influence of the position and cut shape in the sensorial preference of fresh-cut 'Pérola' pineapple

    Directory of Open Access Journals (Sweden)

    Lucimara Rogéria Antoniolli

    2005-12-01

    Full Text Available Procurou-se determinar a melhor porção do fruto, quanto aos teores de sólidos solúveis (SS e acidez titulável (AT e sua preferência sensorial, a ser destinada ao processamento mínimo, bem como o formato de corte preferido para a comercialização na forma de minimamente processado. Os frutos foram descascados manualmente, delimitados em 12 seções de 1cm e fatiados, avaliando-se, cada fatia, quanto ao teor de SS e AT. O delineamento experimental foi em blocos casualizados, onde o fator estudado foi a seção do fruto, com quatro repetições. Os dados foram submetidos à análise de variância e as médias, comparadas pelo teste de Tukey. Sensorialmente, avaliou-se a porção do fruto de maior preferência, utilizando-se, para tanto, do teste de "Ordenação-Preferência". Os resultados foram analisados pelo teste não-paramétrico de Friedman. Os frutos foram ainda avaliados quanto ao formato de corte preferido, através do teste de "Preferência-Pareada". Considerando os teores de SS e AT, não haveria restrições quanto à total utilização do fruto; no entanto, sensorialmente, a porção delimitada pelos 3 centímetros apicais foi pouco aceita, sugerindo que a porção compreendida entre a 4ª e a 12ª seções seja preferencialmente utilizada no processamento mínimo. O corte do abacaxi no formato de fatias foi preferido ao formato em cubos.The purpose of this research was to determine the best portion of pineapple fruit to be used as fresh-cut considering soluble solids (SS, titratable acidity (TA content and preference, as well as the preferred cut shape for its commercialization. Fruits were manually peeled, delimited in 12 sections of 1cm and sliced. Each slice was evaluated for the SS and TA content. The experimental design was in randomized blocks. The studied factor was the fruit section, with four replicates. The data were submitted to the variance analysis and compared by Tukey's test. The preferred fruit portion was

  12. Estimate of respiration rate and physicochemical changes of fresh-cut apples stored under different temperatures Estimativa da taxa de respiração e das mudanças físico-químicas de maçãs minimamente processadas e estocadas sob diferentes temperaturas

    Directory of Open Access Journals (Sweden)

    Cristiane Fagundes

    2013-03-01

    Full Text Available In this study, the influence of storage temperature and passive modified packaging (PMP on the respiration rate and physicochemical properties of fresh-cut Gala apples (Malus domestica B. was investigated. The samples were packed in flexible multilayer bags and stored at 2 °C, 5 °C, and 7 °C for eleven days. Respiration rate as a function of CO2 and O2 concentrations was determined using gas chromatography. The inhibition parameters were estimated using a mathematical model based on Michaelis-Menten equation. The following physicochemical properties were evaluated: total soluble solids, pH, titratable acidity, and reducing sugars. At 2 °C, the maximum respiration rate was observed after 150 hours. At 5 °C and 7 °C the maximum respiration rates were observed after 100 and 50 hours of storage, respectively. The inhibition model results obtained showed a clear effect of CO2 on O2 consumption. The soluble solids decreased, although not significantly, during storage at the three temperatures studied. Reducing sugars and titratable acidity decreased during storage and the pH increased. These results indicate that the respiration rate influenced the physicochemical properties.Neste estudo, a influência da temperatura de armazenamento e da embalagem com atmosfera modificada passiva (AMP na taxa respiratória e nas propriedades físico-químicas de maçãs da variedade Gala (Malus domestica, B. minimamente processadas foi investigada. As amostras foram acondicionadas em embalagens flexíveis e armazenados a 2 °C, 5 °C e 7 °C, durante 11 dias. A taxa de respiração foi gerada para diferentes concentrações de O2 e CO2, obtidas por cromatografia gasosa. Os parâmetros de inibição foram estimados por um modelo matemático baseado na equação de Michaelis-Menten. Foram avaliadas as seguintes propriedades físico-químicas: sólidos solúveis totais, pH, acidez titulável e açúcares redutores. A 2 °C, a taxa de respiração máxima foi

  13. Fresh cut yellow melon (CAC submitted to different type cuts and concentrations of calcion chloride stored under modified passive atmosphereMelão amarelo (CAC minimamente processado submetido a diferentes cortes e concentrações de cloreto de cálcio armazenado em atmosfera modificada passiva

    Directory of Open Access Journals (Sweden)

    Rogério Lopes Vieites

    2012-04-01

    Full Text Available The aim of this work was to evaluate the quality of yellow melon inodorus Valenciano Amarelo (CAC fresh cut submitted to two cut types and with application postharvest of calcium chloride. After preparation cubes and slices melon were immersed in solution with different calcium chloride (CaCl2 concentrations for two minutes, afterwards they were conditioned in trays of expanded polystyrene (EPS, covered by plastic film of low density polyethylene (PEBD, stored in cold camera to 5°C ±1 and analyzed for 8 days. They were evaluated pH, firmness, tritable acidity (AT, soluble solids (SS sugar reducer and ratio. The pH values varied from 5.27 to 5.68. The sugars reducers content and the ratio were superior in the slices compared to the cubes. The melon slices maintained larger firmness values compared to the cubes and in general there was reduction in the values of this parameter along the storage period for all treatments. Concentrations of 1.0 and 1.5% of CaCl2, result in larger values of firmness. The storage temperature and modified passive atmosphere they contributed to quality maintenance of MP melon. Concentrations of up to 1.0% of CaCl2 they could be recommended to maintain the melon quality MP melon yellow inodorus (CAC.Objetivou-se neste trabalho avaliar a qualidade de melão amarelo inodorus (cultivar Valenciano Amarelo CAC minimamente processado (MP submetido a dois tipos de corte e com aplicação pós-colheita de cloreto de cálcio. Após preparo cubos e fatias de melão foram imersos em solução com diferentes concentrações de cloreto de cálcio (CaCl2 por dois minutos, sendo em seguida acondicionados em bandejas de poliestireno expandido (EPS, revestidas por filme plástico de polietileno de baixa densidade (PEBD, armazenados em câmara fria a 5°C ±1 e analisadas durante 8 dias. Foram avaliados pH, firmeza, acidez titulável (AT, sólidos solúveis (SS, açúcar redutor e ratio. Os valores de pH variaram de 5,27 a 5,68. O teor

  14. Advances in Study of the Effect of High Pressure on Quality and Microbes of Fresh-Cut Fruits and Vegetables%高压处理对鲜切果蔬品质与微生物影响的研究进展

    Institute of Scientific and Technical Information of China (English)

    张学杰; 叶志华

    2014-01-01

    提,也是保障鲜切果蔬高压产品品质与安全的有效措施。未来鲜切果蔬高压研究将面向数字化模拟高压对果蔬细胞结构的影响、高压下鲜切果蔬风味的控制、联合高压技术开发及适宜高压加工的鲜切果蔬原料品种的选择等。%This article reviewed the research proceeding on fresh cut fruits and vegetables processed by high pressure technology, which involved in the effect of high pressure on sensory quality, nutritional quality, antioxidant capability, enzymes, microorganisms and cell structure of fresh cut fruits and vegetables. The future research direction was also discussed. High pressure processing (HPP) is a non-thermal food processing method that subjects foods (liquid or solid) to pressures between 50 and 1 000 MPa. The suitable HPP can improve the taste of FCFV products, while higher pressure (>200 MPa) has an adverse effect on the sensory quality. The nutritional quality of FCFV products by HPP is affected by raw material and treatments, lower pressure can increase the antioxidant capability, compared to the adverse effect by the higher pressure. Most enzymes related to quality of FCFV products are steady at lower pressure and even some enzymes were activated at some pressures, enzyme activities are decreased significantly when pressure increased over 400 MPa and some enzymes are inactivated especially by>600 MPa. The degree of inactivation of micro-organisms depends on different factors: micro-organism type, amount of pressure, treatment temperature and time, etc., the inactivation of micro-organisms are observed at HPP, while there will exist a high risk if the micro-organisms are not inactivate completely by HPP, even FCFV products are stored at 4℃. The pressure<300 MPa can not inactivate micro-organisms in FCFV products completely, although it also depends on raw materials and the original populations of micro-organisms. HPP faced challenges against the control of safety of FCFV

  15. PRODUÇÃO E QUALIDADE DE MELÃO CANTALOUPE CULTIVADO COM Á-GUA DE DIFERENES NÍVEIS DE SALINIDADE

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    DAMIANA CLEUMA DE MEDEIROS

    2011-01-01

    Full Text Available In recent years an increase of 15 to 20% occurred in market share melons like Cantaloupes group, which present more attractive organoleptic characteristics and higher commercial value. However it needs more care in production due its higher sensitivity to soil salinity. Effects of soil and water salinity are among the main limiting factors to melon yield and quality at Rio Grande do Norte Sate, Brazil. This work was carried out with the objective of studying the effect of different irrigation water salinity levels on yield and quality of cantaloupe hybrid 'Sedna'. Experimental design was a randomized complete blocks with four replications. Treatments consisted of five salt concentrations in irrigation water (0.54; 1.48; 2.02; 3.03 and 3.9 dS m-1. Yield and quality characteristics evaluated were: number of marketable fruits per plant, yield of marketable fruits, mean weight of fruits, soluble solids content (SS and pulp firmness. An increase on irrigation water salinity level negatively influenced yield of melon hybrid 'Sedna'. Yield loss in response to salinity was due to decrease in number of fruits per plant. Mean values of soluble solids and pulp firmness were not influenced by irrigation water salinity.

  16. Efeito do tipo de corte nas características físico-químicas e microbiológicas do melão 'cantaloupe' (Cucumis melo L. Híbrido hy-Mark) minimamente processado

    National Research Council Canada - National Science Library

    Oliveira, Ariane Cordeiro de; Figueiredo, Raimundo Wilane de; Maia, Geraldo Arraes; Alves, Ricardo Elesbão; Souza Filho, Men de Sá Moreira de; Sousa, Paulo Henrique Machado de

    2007-01-01

    O objetivo deste trabalho foi avaliar o efeito de dois tipos de cortes (manual e mecânico) nas características físico-químicas e microbiológicas do melão 'Cantaloupe' minimamente processado e refrigerado...

  17. Cold plasma-activated hydrogen peroxide aerosol inactivates Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria innocua and maintains quality of grape tomato, spinach and cantaloupe.

    Science.gov (United States)

    Jiang, Yunbin; Sokorai, Kimberly; Pyrgiotakis, Georgios; Demokritou, Philip; Li, Xihong; Mukhopadhyay, Sudarsan; Jin, Tony; Fan, Xuetong

    2017-05-16

    The purpose of this study was to investigate the efficacy of aerosolized hydrogen peroxide in inactivating bacteria and maintaining quality of grape tomatoes, baby spinach leaves and cantaloupes. Stem scars and smooth surfaces of tomatoes, spinach leaves, and cantaloupe rinds, inoculated with Escherichia coli O157:H7, Salmonella Typhimurium and Listeria innocua, were treated for 45s followed by additional 30min dwell time with hydrogen peroxide (7.8%) aerosols activated by atmospheric cold plasma. Non-inoculated samples were used to study the effects on quality and native microflora populations. Results showed that two ranges of hydrogen peroxide droplets with mean diameters of 40nm and 3.0μm were introduced into the treatment chamber. The aerosolized hydrogen peroxide treatment reduced S. Typhimurium populations by 5.0logCFU/piece, and E. coli O157:H7 and L. innocua populations from initial levels of 2.9 and 6.3logCFU/piece, respectively, to non-detectable levels (detection limit 0.6logCFU/piece) on the smooth surface of tomatoes. However, on the stem scar area of tomatoes, the reductions of E. coli O157:H7, S. Typhimurium, and L. innocua were only 1.0, 1.3, and 1.3 log, respectively. On the cantaloupe rind, the treatment reduced populations of E. coli O157:H7, S. Typhimurium and L. innocua by 4.9, 1.3, and 3.0logCFU/piece, respectively. Under the same conditions, reductions achieved on spinach leaves were 1.5, 4.2 and 4.0 log for E. coli O157:H7, S. Typhimurium and L. innocua, respectively. The treatments also significantly reduced native aerobic plate count, and yeasts and mold count of tomato fruits and spinach leaves. Furthermore, firmness and color of the samples were not significantly affected by the aerosolized hydrogen peroxide. Overall, our results showed that the efficacy of aerosolized hydrogen peroxide depended on type of inoculated bacteria, location of bacteria and type of produce items, and aerosolized hydrogen peroxide could potentially be used to

  18. Efeito do tipo de corte nas características físico-químicas e microbiológicas do melão 'cantaloupe' (Cucumis melo L. Híbrido hy-Mark minimamente processado Effect of type of cutting on the physical chemical and microbiological characteristics of 'Cantaloupe' melon (Cucumis melo L. Hybrid hy-Mark minimally processed

    Directory of Open Access Journals (Sweden)

    Ariane Cordeiro de Oliveira

    2007-08-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito de dois tipos de cortes (manual e mecânico nas características físico-químicas e microbiológicas do melão 'Cantaloupe' minimamente processado e refrigerado. Frutos com grau de maturação adequado foram selecionados, lavados, sanificados (200 ppm de cloro ativo/2 minutos e processados de acordo com o tipo de corte. Os frutos utilizados para o corte mecânico foram descascados em máquina descascadora e após a retirada das sementes, submetidos ao corte com auxílio de máquina de corte. Os destinados ao corte manual foram descascados e cortados com auxílio facas, colocados em imersão em solução de hipoclorito de sódio (20 ppm de cloro ativo por 30 segundos e acondicionados em embalagens flexíveis PET, armazenados a 4°C ± 1°C e avaliados a cada três dias por um período de 15 dias. Ao final dos experimentos, concluiu-se que para o processamento mínimo de melão 'Cantaloupe', o corte manual foi o mais indicado, por apresentar melhor estabilidade das características de cor, textura, pH, umidade e contagens microbiológicas durante o armazenamento.The purpose of this work was to evaluate the effect of two types of cutting (manual and mechanic on the physical-chemical and microbiological characteristics of processed and refrigerated 'Cantaloupe' melon. The fruits in the appropriate stage of ripening were selected, washed, sanitized (200ppm of active chlorine/2 minutes and processed in agreement with types of cutting. The fruits used for the mechanical cutting were cutting in peeling machine and after at retreat of the seeds, submitted to the cutting with aid of cutting machine. The fruits destined at manual cutting were peeled and cut with aid of knives, immerged in chlorinated water (20 mg.L-1 of active chlorine for 30 seconds and conditioned in PET flexible packing, stored at 4°C ± 1°C and were carried out each three days during 15 days. At the end of the experiments it was

  19. Divergência genética entre cinco genótipos de melão rendilhado Genetic divergence among five muskmelon cultivars

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    Adriana Antonieta do Nascimento Rizzo

    2002-06-01

    Full Text Available Estimou-se a divergência genética entre cinco genótipos de melão rendilhado (Cucumis melo var. reticulatus Naud. (JAB-20, JAB-21, JAB-22, JAB-23 e 'Bônus nº 2' e determinou-se qual a contribuição relativa das 16 características avaliadas [nº médio de flores masculinas, hermafroditas/planta; produção total de frutos/m², peso médio dos frutos comerciáveis; diâmetro médio transversal e longitudinal do fruto (DMTF e DMLF; diâmetro médio transversal da inserção do pedúculo (DMTP; espessura média do mesocarpo e epicarpo (EMM e EME; diâmetro médio longitudinal e transversal do lóculo (DMTL e DMLL; proporção da cavidade (PC; desprendimento de sementes (DS; teor de sólidos solúveis totais (SST, pH e acidez titulável (AT] na divergência gen��tica. Obtiveram-se dois grupos de similaridade: I- JAB-20, JAB-21 e 'Bônus nº2' e II- JAB-22 e JAB-23. As características DMLF, DMTP, DMLL, DS e SST foram as que mais contribuíram para a divergência genética entre os genótipos.The genetic divergence of five cultivars of muskmelon was estimated (Cucumis melo var. reticulatus Naud (JAB-20, JAB-21, JAB-22, JAB-23 and 'Bônus nº2' and the relative contribution of each 16 characteristics were determined (number of male flowers per plant; total production of fruit, weight of fruits; longitudinal and transversal diameters of fruits; thickness and color of flesh and skin; longitudinal and transversal loculos diameter of fruits; seed loosing; netting thickness; and % total solvers solids, pH and total acidity in genetic divergence. Two groups of similarity were formed between the genitors by the values of D², one of then was constituted of the JAB-20 and JAB-21 and 'Bônus nº 2' genotypes, and another of the JAB-22 and JAB-23. The characteristics of longitudinal loculos diameters, longitudinal diameter of fruits, transversal diameter of peduncle insertion, % total solvers solids and seed loosing contributed to for genetic

  20. Muskmelon seed germination and seedling development in response to seed priming Germinação de sementes e desenvolvimento de plântulas de melão em resposta ao condicionamento osmótico

    Directory of Open Access Journals (Sweden)

    Warley Marcos Nascimento

    2003-02-01

    Full Text Available Important factors affecting seed priming have not been extensively reported in muskmelon (Cucumis melo L. studies. The optimization of the seed priming technique becomes very important at the commercial scale. Little information has been reported on seedling development of muskmelon subsequent to seed priming. Seeds of muskmelon were primed in darkness at 25°C in different solutions and three osmotic potentials. Seeds were also primed with and without aeration during different periods. In relation to osmotic solutions, an osmotic potential around -1.30 MPa is most adequate for muskmelon priming. Salt solutions gave better germination rate but were deleterious for seed germination, especially at higher osmotic potentials. Aeration of the soaking salt solution gave faster germination at 17°C, and because of the early germination, these treatments probably presented a better seedling development. Deleterious effect on total seed germination was observed for long soaking periods with aeration. Fungal growth increased on seeds primed in aerated solutions. Seeds from priming treatments had a better germination rate and seedling development under 17 and 25°C.Importantes fatores afetando o condicionamento osmótico não têm sido extensivamente relatados em sementes de melão (Cucumis melo L.. A otimização do condicionamento osmótico é extremamente importante em uma escala comercial. Poucas informações têm sido relatadas quanto ao desenvolvimento de plântulas em resposta ao condicionamento osmótico de sementes de melão. Sementes de melão foram condicionadas a 25°C, na ausência de luz, em diferentes soluções osmóticas utilizando três potenciais osmóticos para cada solução. Em outro estudo, sementes foram condicionadas com ou sem aeração durante vários períodos. Indiferentemente das soluções osmóticas, o potencial osmótico em torno de - 1,30 MPa foi mais adequado para o condicionamento osmótico. Sementes condicionadas em

  1. 辽宁省甜瓜新病害——果腐病病原菌生物学特性研究%Studies on Biological Characteristics of Fruit Rot Pathogen — A New Muskmelon Disease in Liaoning Province

    Institute of Scientific and Technical Information of China (English)

    侯悦; 刘志恒; 曹友文; 赵廷昌

    2013-01-01

    The pathogen of muskmelon fruit rot was isolated from the samples of muskmelon from Liaoning Province. The casual agent was identified as AG-4 HGI of Rhizoctonia solani by the studies on morphology, pathogenicity, anastomosis groups and rDNA-ITS. The pathogenic biological characteristics of muskmelon fruit rot were studied in this paper. The result showed that the best medium for mycelial growth was Muskmelon juice culture medium. The temperature ranged for mycelial growth was 5-40 ℃, 28 ℃was the optimum; the best pH was 7. The effect of light on mycelial growth was not evident. Myeelial growth was in favor of soluble starch and Peptone. The ideal sclerotia formation was at 25 ℃, pH 6-8, Richard culture medium. The suitable carbon source for the formation of sclerotia was Sorbitol. The beneficial nitrogen source for the formation of sclerotia was KNO3. The sclerotia could germinate in 10 kinds of nutrition. The proper temperature was 15-40 ℃ , and 28 ℃ was the optimum. Dark condition was conductive to sclerotium germination. The best carbon source and nitrogen source for sclerotium germination are Malt Sugar and Peptone. Mycelial lethal temperature was 50℃, 10 min.The sclerotia lethal temperature was 531, 10 min.%针对辽宁省甜瓜新病害——茄丝核菌(Rhizoctonia solani)引起的果腐病,对其病原菌进行了生物学测定.结果表明:病原菌菌丝生长以甜瓜煎汁培养基为最适;菌丝在5~40℃范围内均能生长,最适温度为28 ℃;最适pH值为7;光照对菌丝生长影响较小;适宜菌丝生长的碳、氮源分别为可溶性淀粉和蛋白胨.菌核形成的适宜条件为25℃,pH值6~8,理查培养基,最适碳源为山梨醇,最适氮源为KNO3.菌核在10种供试营养物质中均能萌发;在15~ 40℃范围内菌核均可萌发,28℃为最适温度,黑暗条件有利于菌核萌发;以麦芽糖为碳源的PA培养基和以蛋白胨为氮源的查氏培养基有利于菌核

  2. Response of cotton, alfalfa, and cantaloupe to foliar-deposited salt in an arid environment. [Gossypium hirsumtum L. ; Medicago sativa L. ; Cucumis melo L

    Energy Technology Data Exchange (ETDEWEB)

    Hofmann, W.C.; Karpiscak, M.M.; Bartels, P.G.

    The cooling towers at the Palo Verde Nuclear Generating Station (PVNGS), located 80 km west of Phoenix, AZ, will release as estimated 2.1 Mg/d of particulates (primarily salts) into the atmosphere when the station is in full operation. The saline drift will disperse and settle onto agricultural fields surrounding the station. Field studies were conducted in 1983 to investigate the influence of foliar-applied saline aerosol on crop growth, foliar injury, and tissue elemental concentration on cotton (Gossypium hirsutum L.), alfalfa (medicago sativa L.), and cantaloupe (Cucumis melo L.) in an arid environment. The treatment aerosol solutions simulated treated wastewater effluent and included all essential plant nutrients and other elements, including trace concentrations of heavy metals. The treatments included unsprayed plots, and plots sprayed with salt solutions at 0 (distilled water), 8, 83, and 415 kg/(ha yr). The alfalfa received an additional 829 kg/(ha yr) treatment. The species were evaluated in separate experiments on Mohave clay loam and Sonoita sandy loam soils (Typic Haplargid) near Marana, AZ. Cotton treated with 415 kg/(ha yr) had significantly less chlorosis and tended to be slightly taller than the cotton in the unsprayed plots. The alfalfa treated at a rate of 829 kg/(ha yr) showed significantly more leaf margin necrosis than did the unsprayed alfalfa. In the cantaloupe, there were no visually apparent differences among salt treatments. Hand-harvested cotton plots had a significant reduction is seed cotton yield at the 415 kg/(ha yr) treatment. A similar though nonsignificant, trend towards reduced yield with increased salt treatment was observed in machine-harvested cotton plots.

  3. Muskmelon Disease Forecasting Based on Optimized BP Neural Network%基于优化神经网络的温室厚皮甜瓜病害预测

    Institute of Scientific and Technical Information of China (English)

    王福顺; 孙小华

    2012-01-01

    在温室环境中,厚皮甜瓜较易感染一些病害,而传统的病害预测模型收敛速度慢,易在局部局限在极小值,为准确预测温室厚皮甜瓜病害,在BP神经网络的基础上进行优化,引入了遗传算法,在全局最优解的附近进行局部搜索,以遗传算法的全局搜索能力克服了传统神经网络的局部极小值问题与收敛速度缺陷.经以Matlab对试验数据进行仿真分析,证实引入遗传优化算法进行温室厚皮甜瓜病害预测误差显著减小,取得了较理想的拟合结果.%In the environment of greenhouse,muskmelon is often infected by diseases. The traditional neural network algorithm converges slowly,easy to limited to the minimum in the local convergence. In this paper,genetic algorithm was led into BP network to overcome the defects by its global search ability. The Matlab simulation analysis of test data confirmed that the introduction of genetic optimization algorithm significantly reduced the prediction errors of greenhouse muskmelon disease,and obtained better fitting results.

  4. Comparison of Pollen Germination Rate of Fruit Set in Different Muskmelon Under Protected Cultivation%设施栽培下不同品种薄皮甜瓜花粉萌发及坐果率的比较

    Institute of Scientific and Technical Information of China (English)

    高青海; 贾双双; 苗永美

    2015-01-01

    对早春大棚栽培的薄皮甜瓜,采用花粉离体培养和氯化三苯基四氮唑( TTC )染色观察法,利用显微镜观察5个品种薄皮甜瓜花粉的生活力,并对其花粉萌发及坐果情况进行比较。结果表明,在设施栽培过程中,薄皮甜瓜品种‘青皮酥瓜’和‘长花皮酥瓜’花粉萌发率高,萌发率分别为85.4%和75.8%,而且花粉管伸长快,易于授粉,坐果率较高,其中‘长花皮酥瓜’的坐果率为37%,适合早春设施栽培。%Using pollen in vitro culture techniques and triphenyl tetrazolium chloride( TTC)staining method,5 varieties of muskmelon pollen viability are observed under microscope,and pollen germination and their fruit set were compared,in early spring protected cultivation. The results showed that the cultivation process,muskmelon varieties‘Qing pi su gua’and‘Chang hua pi su gua’pollen germination rate,male pollen germination rate were respectively 85. 4% and 75. 8%;and pollen tube of growth was quick,fruit set rate was higher,the fruit set of‘Chang hua pi su gua’was 37%,which is suitable for early spring cultivation.

  5. Fatty acid composition and antioxidant activity of oils from two cultivars of Cantaloupe extracted by supercritical fluid extraction

    Directory of Open Access Journals (Sweden)

    Sy Ling, Hoe

    2010-03-01

    Full Text Available The effect of supercritical fluid extraction (SFE fractionation of three oil fractions (1st, 2nd, 3rd fraction on the fatty acid composition and antioxidant activity of oils from two cultivars of cantaloupe were investigated. Rock melon oil (RMO and Golden Langkawi oil (GLO were extracted using SFE and the major fatty acids for both cultivars were linoleic, oleic, palmitic, and stearic acid. The SFA decreased from 15.78 to 14.14% in RMO 1st fraction, and MUFA decreased from 18.30 to 16.56% in RMO 2nd fraction, while PUFA increased from 65.9 to 69.30% in RMO 3rd fraction. On the other hand SFA decreased from 16.35 to 13.91% in GLO 1st fraction, and MUFA decreased from 17.50 to 15.57% in GLO 2nd fraction, while PUFA increased from 66.15 to 70.52% in GLO 3rd fraction. The different fractions of the two oils showed high antioxidant activity in reducing the oxidation of β-carotene in beta-carotene bleaching assay (BCB and the quenching of 1,1-diphenyl-2-picrylhydrazyl (DPPH.El efecto del fraccionamiento mediante extracción con fluido supercrítico de tres fracciones (fracción 1ª, 2ª y 3ª sobre la composición de ácidos grasos y actividad antioxidante de aceites de dos variedades de melón fué investigado. Aceites de melón de los cultivares Rock (RMO y Golden Langkawi GLO fueron extraídos usando SFE y los principales ácidos grasos en cada cultivar fueron ácido linoleico, oleico, palmítico y esteárico. Los ácidos grasos saturados (SFA disminuyeron desde 15.78 a 14.14% en la 1ª fracción de RMO y los ácidos grasos monoinsaturados (MUFA disminuyeron desde 18.30 a 16.56% en la 2ª fracción de RMO, mientras que los ácidos grasos poliinsaturados (PUFA aumentaron de 65.9 a 69.30% en la 3ª fracción de RMO. Por otra parte, SFA disminuyo de 16.35 a 13.91% en la primera fracción de GLO y MUFA disminuyo de 17.50 a 15.57% en la 2ª fracción de GLO, mientras que PUFA aumento de 66.15 a 70.52% en la 3ª fracción de GLO. Las diferentes

  6. Estimation model for daily transpiration of greenhouse muskmelon in its vegetative growth period%温室甜瓜营养生长期日蒸腾量估算模型

    Institute of Scientific and Technical Information of China (English)

    张大龙; 李建明; 吴普特; 李玮黎; 赵志华; 徐菲; 李俊

    2013-01-01

    建立了基于温室环境参数、甜瓜生长发育参数和土壤水分参数的温室甜瓜日蒸腾量估算模型,以研究温室条件下甜瓜蒸腾量的估算方法.根据温室内特定环境对PenmanMonteith方程中空气动力项进行修正,推导出了适于计算温室条件下参考作物蒸腾量的温室环境因子子模型;以甜瓜叶面积指数为自变量构建了作物因子子模型,模型形式为线性函数;以土壤相对有效含水量为自变量构建了土壤水分因子子模型,模型形式为对数函数.采用分期播种法,根据周年不同播期实测数据对模型参数进行估计和分析.采用土壤相对含水量分别为80%、70%、60%的实测蒸腾数据,对模型在充分灌溉和节水灌溉条件下的预测精度进行了检验,模拟值的平均相对误差分别为11.5%、16.2%、16.9%.所建蒸腾模型是对PenmanMonteith公式在温室环境和节水灌溉条件下的有益探索,具有重要推广应用价值.%For developing an estimation method of muskmelon transpiration in greenhouse,an estimation model for the daily transpiration of greenhouse muskmelon in its vegetative growth period was established,based on the greenhouse environmental parameters,muskmelon growth and development parameters,and soil moisture parameters.According to the specific environment in greenhouse,the item of aerodynamics in Penman-Monteith equation was modified,and the greenhouse environmental sub-model suitable for calculating the reference crop evapotranspiration in greenhouse was deduced.The crop factor sub-model was established with the leaf area index as independent variable,and the form of the model was linear function.The soil moisture sub-model was established with the soil relative effective moisture content as independent variable,and the form of the model was logarithmic function.With interval sowing,the model parameters were estimated and analyzed,according to the measurement data of different sowing

  7. 软肉型厚皮甜瓜新品种湖甜1号的选育%Breeding of Hutian No.1, a New Muskmelon Cultivar with Soft Flesh and Thick Peel

    Institute of Scientific and Technical Information of China (English)

    叶飞华; 金永祥; 张志友; 陈丽萍; 杨景华; 张明方

    2013-01-01

    Hutian No.1 was a new mid-maturing, high-quality and high-yield muskmelon cultivar by taking L6 as female parent and L26 as male parent. It was bred by Huzhou Agricultural Technology Extension Station, Agriculture and Biotechnology College of Zhejiang University and Huzhou Academy of Agricultural Sciences in 2011. It was a new muskmelon cultivar with soft flesh and thick peel. The results showed that, under the facility cultivation conditions in spring, its whole growth period was about 132 days, and the fruit growing period was about 45 days, with the average fruit weight of 1.6 kg and the yield of about 1 900-2 000 kg/667 m2. And its fruit was oval, and the fruit shape index of about 1.2. Its peel was green and white with irregular thin fine lines on the fruit surface accidently. The fruit flesh was pale green with the thickness of about 3.8-4.0 cm, and the central soluble solids content was about 15%. The flesh was soft with light fragrance and great taste. Its flowering period was concentrated, and it was easy to bear fruits and was moderately resistant to gummy stem blight and blight.%  湖甜1号是湖州市农作物技术推广站、浙江大学农业与生物技术学院、湖州市农业科学研究院以L6为母本、L26为父本进行杂交,于2011年育成的中熟、优质、丰产的软肉型厚皮甜瓜新品种.试验结果表明,湖甜1号春季设施栽培全生育期132 d左右,果实发育期45 d左右;平均单果质量1.6 kg,667 m2产量1900~2000 kg;果实椭圆形,果形指数1.2左右,果皮绿白色,果面偶有不规则形稀细纹;果肉淡绿色,肉厚3.8~4.0 cm,中心可溶性固形物含量15%左右,口感软,有淡香味,口感纯正;花期集中,易坐果、整齐;中抗蔓枯病和枯萎病.

  8. Sensory and instrumental analysis of medium and long shelf-life Charentais cantaloupe melons (Cucumis melo L.) harvested at different maturities.

    Science.gov (United States)

    Lignou, Stella; Parker, Jane K; Baxter, Charles; Mottram, Donald S

    2014-04-01

    The flavour profiles of two genotypes of Charentais cantaloupe melons (medium shelf-life and long shelf-life), harvested at two distinct maturities (immature and mature fruit), were investigated. Dynamic headspace extraction (DHE), solid-phase extraction (SPE), gas chromatography-mass spectrometry (GC-MS) and gas chromatography-olfactometry/mass spectrometry (GC-O/MS) were used to determine volatile and semi-volatile compounds. Qualitative descriptive analysis (QDA) was used to assess the organoleptic impact of the different melons and the sensory data were correlated with the chemical analysis. There were significant, consistent and substantial differences between the mature and immature fruit for the medium shelf-life genotype, the less mature giving a green, cucumber character and lacking the sweet, fruity character of the mature fruit. However, maturity at harvest had a much smaller impact on the long shelf-life melons and fewer differences were detected. These long shelf-life melons tasted sweet, but lacked fruity flavours, instead exhibiting a musty, earthy character.

  9. Sensory and instrumental analysis of medium and long shelf-life Charentais cantaloupe melons (Cucumis melo L.) harvested at different maturities

    Science.gov (United States)

    Lignou, Stella; Parker, Jane K.; Baxter, Charles; Mottram, Donald S.

    2014-01-01

    The flavour profiles of two genotypes of Charentais cantaloupe melons (medium shelf-life and long shelf-life), harvested at two distinct maturities (immature and mature fruit), were investigated. Dynamic headspace extraction (DHE), solid-phase extraction (SPE), gas chromatography–mass spectrometry (GC–MS) and gas chromatography–olfactometry/mass spectrometry (GC–O/MS) were used to determine volatile and semi-volatile compounds. Qualitative descriptive analysis (QDA) was used to assess the organoleptic impact of the different melons and the sensory data were correlated with the chemical analysis. There were significant, consistent and substantial differences between the mature and immature fruit for the medium shelf-life genotype, the less mature giving a green, cucumber character and lacking the sweet, fruity character of the mature fruit. However, maturity at harvest had a much smaller impact on the long shelf-life melons and fewer differences were detected. These long shelf-life melons tasted sweet, but lacked fruity flavours, instead exhibiting a musty, earthy character. PMID:24262549

  10. The Pigment Aztec Marigold and the Muskmelon Interplanting Cultivation Technique Studies%色素万寿菊与香瓜套作丰产栽培技术研究

    Institute of Scientific and Technical Information of China (English)

    黄前晶

    2011-01-01

    通过菊瓜“3+1+3”立体丰产栽培方式,获得色素万寿菊平均产量5842.5kg/667m2,比对照增产28%,香瓜产量2100kg/667m2,菊瓜套作纯效益5883.6元/667m2,达到了菊瓜双赢的效果。%Through the "3+1+3" three-dimensional high-yield cultivation mode of the chrysanthemum and melon, the average output of 3 842.5 kg/667m2 for pigment aztec marigold was obtained by 28% yield increase. Muskmelon output reached 2 1(30 kg/667m2. The pure benefit for Chrysanthemum and melon interplant is 3 883.6 Yuan /667m2. This cultivation technique is both good for the chrysanthemum and melon.

  11. 维生素C浸种对盐胁迫下甜瓜种子萌发的影响%Effects of Vitamine C on Seed Germination of Muskmelon Under Salt Stress

    Institute of Scientific and Technical Information of China (English)

    王薇; 王亚君; 陈志刚

    2013-01-01

      本文以甜瓜品种龙甜六号为试材,研究了不同浓度的维生素C对200mmol/L NaCl胁迫下甜瓜种子萌发的影响。研究结果表明一定浓度的维生素C溶液能提高盐胁迫条件下甜瓜种子的发芽率,促进幼苗生长,能够缓解盐胁迫对甜瓜种子萌发的危害。%Melon varieties Long Tian No.6 test materials,the effects of different concentrations of vitamin C on 200mmol/LNaCl stress of melon seed germination.Research results show that a certain concentration of vitamin C solution can improve the salt stress conditions,melon seed germination rate, promoted the growth of seedlings,easing salt stress on Germination of Muskmelon Seeds harm.

  12. Crescimento do melão Pele de Sapo, em níveis de salinidade e estágio de desenvolvimento da planta Growth of 'Pele de Sapo' muskmelon under salinity levels and development stage of plant

    Directory of Open Access Journals (Sweden)

    Damiana C. de Medeiros

    2012-06-01

    Full Text Available As áreas de cultivo com intensa evaporação, deficiência em drenagem e uso inadequado de fertilizantes, têm aumentado os problemas com a salinidade, prejudicando o rendimento das culturas. O experimento foi conduzido com o objetivo de se avaliar a alocação de massa seca do meloeiro, em função dos diferentes níveis de salinidade da água de irrigação e estágios de desenvolvimento da planta, em Mossoró, RN. O delineamento experimental utilizado foi o de blocos ao acaso, em parcelas subdivididas apresentando, nas parcelas, cinco níveis de salinidade da água de irrigação (0,54, 1,48, 2,02, 3,03 e 3,90 dS m-1 e, nas subparcelas, quatro épocas de coleta de plantas em função dos estágios de seu desenvolvimento (15, 30, 45 e 60 dias após o transplante - DAT correspondendo às fases de crescimento inicial, floração plena, frutificação plena e anterior ao início da colheita, respectivamente, com quatro repetições. Todos os parâmetros de crescimento avaliados foram afetados pela salinidade da água de irrigação. O efeito da salinidade da água sobre a área foliar específica e a massa seca das folhas, foi variável de acordo com a fase de desenvolvimento das plantas. As variáveis mais afetadas pela salinidade da água de irrigação foram a área foliar e a massa seca de frutos, com redução de 28,9 e 24,6%, respectivamente. O maior acúmulo de massa seca no meloeiro Pele de Sapo ocorreu no período entre 30 e 45 dias após o transplantio.The region of Mossoró, RN, Brazil, underwent increasing problems with soil salinity and melon crop yields, mainly in areas with intense evaporation, deficient drainage and inadequate fertilizer use. With this concern, dry mass accumulation in different muskmelon plant organs was evaluated in a trial combining different irrigation water salinity levels and crop growth stages. The experiment was conducted in completely randomized block design with split plot arrangement, having four

  13. 辽宁省甜瓜果腐病病原菌鉴定及生物学特性初探%Identification and Biological Characteristics of Muskmelon Fruit Rot Pathogen in Liaoning Province

    Institute of Scientific and Technical Information of China (English)

    刘志恒; 侯悦; 胡积祥; 滕晓菲; 黄欣阳; 王世维; 赵廷昌

    2013-01-01

    Muskmelon fruit rot caused by Rhizoctonia sp. is a new disease first found in Liaoning Province in recent years. The disease appears more serious on greenhouse muskmelon. The casual agent was identified as AG-4 HGI of Rhizoctonia solani by the studies of the morphology, pathogenicity, anastomosis groups and ribosomal DNA-ITS. The biological characteristics of the results showed that the best mycelium growth was obtained at 28 ℃ and pH 6.0 - 8.0; The melon juice culture medium was most conducive to mycelium growth in the 10 tested media, The optimum one was soluble starch in the 9 tested carbon sources, the optimum nitrogen source was peptone. The effect of light on the mycelial growth was not evident. The ideal sclerotium generation was at 25 ℃, pH 7.0, in darkness and with Czapek culture medium. The beneficial carbon source for the formation of sclerotia was Sorbitol; The beneficial nitrogen source for the formation of sclerotia was KNO3. Sclerotium germination was well with carrot juice culture medium; In the 9 tested carbon sources and 10 tested nitrogen sources, sclerotium germination was in favor of malt sugar and peptone; The optimum temperature for sclerotium germination was 25 ℃; The optimum pH is 5.0 - 8.0; Dark conditions was benefit for sclerotium germination. The mycelial lethal temperature was at 50 ℃ for 10 min. The lethal temperature for sclerotium was at 53 ℃ for 10 min.%由丝核菌引起的甜瓜果腐病是辽宁省近年发生的新病害,在棚室甜瓜生产中发生渐趋严重.根据病原菌形态、致病性、菌丝融合群和rDNA-ITS序列分析,确定其病原菌为茄丝核菌(Rhizoctonia solani),AG-4 HGI融合群.病原菌生物学特性测定结果表明,菌丝生长最适温度28℃;最适pH 6.0~8.0;供试10种培养基中,在甜瓜煎汁培养基中菌丝生长最快;供试9种碳源和10种氮源中,最适碳源为可溶性淀粉,最适氮源为蛋白胨;光照对菌丝生长影响较小.菌

  14. Complementos nutricionales para el rendimiento y nutrición del cultivo de melón con fertirriego y acolchado Nutritional supplements for fruit yield and nutrition of muskmelon under fertigation and plastic mulch

    Directory of Open Access Journals (Sweden)

    Luis Mario Tapia Vargas

    Full Text Available El melón fertirrigado es sometido a uso intensivo de insumos y aplicación de complementos nutricionales al follaje. El objetivo fue evaluar el efecto de la aplicación de foliares orgánicos e inorgánicos en la condición nutrimental, desarrollo, rendimiento y calidad del fruto del melón con acolchado y fertirriego. En 2006 se evaluaron los siguientes tratamientos: 1 testigo con fórmula de fertilización 180-100-200 (N-P2O5-K2O; 2 tratamiento 1 más activadores orgánicos y foliares inorgánicos (AO+F; 3 tratamiento 1 más biofertilizantes orgánicos foliares y al suelo (OR; 4 tratamiento 1 más hormonas e inorgánicos al follaje (H+F. En 2007 se estudiaron los tratamientos 1, 2, 3, y 4 de 2006 y se adicionaron dos tratamientos: 5 tratamiento 1 más bioactivadores orgánicos al suelo más foliares inorgánicos (B+F; y 6 reducción de 50% de la fertilización del tratamiento 1 más biofertilizantes orgánicos foliares y al suelo (RE. Se determinaron las características: rendimiento de fruto calidad bruce y nacional; °Bx en frutos, N-NO3 y K+ (mg L-1 en extracto celular de pecíolo (ECP; N, P y K foliar total (g L-1; longitud de guía (m; biomasa foliar y radical (g planta-1. En 2006, H+F superó significativamente al testigo con 16 t ha--1 más de fruto calidad bruce; mientras que en 2007 H+F y OR pudieron superarlo con 6.6 y 5.3 t ha-1, respectivamente. H+F fue superior al testigo en ambos años. Además, hubo un efecto significativo de tratamientos en la nutrición de N y P foliar total (g L-1; no hubo diferencias en K total (g L-1 y en N-NO3 (mg L-1 en ECP. La utilización de foliares en melón fertirrigado si tiene efecto en incremento de rendimiento de fruto calidad bruce y en la nutrición, pero no en la biomasa del cultivo.Fertigated muskmelon is cultivated under intensive use of fertilizer and foliar nutritional supplements. The aim of this research was to evaluate the effect of organic and inorganic foliar applications upon the

  15. EFICIÊNCIA DE MÉTODOS ALTERNATIVOS UTILIZANDO ATMOSFERA MODIFICADA PASSIVA, NO CONTROLE DA PODRIDÃO DE MELÃO CANTALOUPE

    Directory of Open Access Journals (Sweden)

    Cynthia Renata Lima Sá

    2008-01-01

    Full Text Available This research avollue the efficiency of Potassium permanganate (KMnO4 plus other alternatives to control rot of melons. The trials were carried out at Embrapa Agroindústria Tropical located in Fortaleza, Ceara state, Brazil. Cantaloupe melons, hybrid 'Vera Cruz', were harvested from Dinamarca Indústria Agricola farm, located in the 304 BR km 38 - Nova Betânia - Mossoró, Rio Grande do Norte State. Fruits were sorted for uniformity, rinsed with alcohol 70%, inoculated with Fusarium pallidoroseum, and assembled for treatments with 600ppb of 1-methyiciclopropene (1- MCP; 1, 2 or 3g of Potassium permanganate; Carnauba wax; and Funginat (a blend essential oil. Five fruits were placed per box, and each box taken as a repetition. Fruits were also divided into two lots: not packed and packed in Xtend. Vermiculite sachets impregnated with potassium permanganate (KMnO4 were distributed according to the weight of the fruits in each box. Upon treatments, fruits were stored under low temperature, 3 ± 2°C, and relative humidity of 85 ± 2% for 14 days. After that period, fruit packages and boxes were removed from storage, low temperature and room temperature (23 ± 2°C and 90 ± 2% RH, respectively. Evaluations were loss of mass and grading from 15th to 18th day of storage. The experimental design was completely randomized in a factorial system 5x2, being five treatments (1- MCP, KMnO4, Carnaúba wax, Funginat, and control fruits, and two modified atmospheres (with and without X-tend. Results on disease incidence were written in percentage per box, transformed into arc sine and degrees of quadrant. The analysis of variance was performed with the aid of the ESTAT - System for Statistics Analysis, version 1.0, UNESP. Results showed significant difference principally regarding the use of packaging, suggesting that the use of modified atmosphere affects the quality of melons by increasing fruit shelf life. It has been also concluded that association of

  16. Public Health Relevance of Cross-Contamination in the Fresh-Cut Vegetable Industry.

    Science.gov (United States)

    Chardon, Jurgen; Swart, Arno; Evers, Eric; Franz, Eelco

    2016-01-01

    Although quantitative studies have revealed that cross-contamination during the washing stage of fresh produce occurs, the importance of cross-contamination in terms of public health relevance has rarely been assessed. The direct distribution of initially contaminated leafy vegetables to a multitude of servings by cutting and mixing also has not been addressed. The goal of this study was to assess the attribution of both contamination pathways to disease risk. We constructed a transparent and exploratory mathematical model that simulates the dispersion of contamination from a load of leafy greens during industrial washing. The risk of disease was subsequently calculated using a Beta-Poisson dose-response relation. The results indicate that up to contamination loads of 10(6) CFU the direct contamination route is more important than the indirect route (i.e., cross-contamination) in terms of number of illnesses. We highlight that the relevance of cross-contamination decreases with more diffuse and uniform contamination, and we infer that prevention of contamination in the field is the most important risk management strategy and that disinfection of washing water can be an additional intervention to tackle potentially high (>10(6) CFU) point contamination levels.

  17. Detection of fresh-cut produce processing residues on food contact surface materials using hyperspectral imaging

    Science.gov (United States)

    To reduce the risk of foodborne-illness, produce processors currently clean and sanitize food contact surfaces daily before production starts. Current methods to verify the efficacy of cleaning procedures include visual inspection and direct surface sampling using ATP bioluminescence assays and cul...

  18. FRUIT JUICES AS AN ALTERNATIVE TECHNIQUE FOR CONSERVATION OF FRESH-CUT BANANA

    OpenAIRE

    ANDERSON ADRIANO MARTINS MELO; LEONARDO THOMAZ DINIZ; ADRIANO DO NASCIMENTO SIMÕES; ROLF PUSCHMANN

    2014-01-01

    Browning discoloration after cutting is detrimental for the quality of a number of fruits and vegetables, such as banana, apple, pear, potato, and some roots such as cassava, yam, and others. Browning and softening compromise banana after cut shelf-life in a few hours under cold storage. Therefore, anti-browning compounds have been applied to slices before packing. Some commonly used substances are calcium chloride, ascorbic acid, cysteine and citric acid, in immersed inchemical mixtures. Rec...

  19. EFFECT OF COLD PLASMA TREATMENT ON THE FUNCTIONAL PROPERTIES OF FRESH-CUT APPLES.

    Science.gov (United States)

    Ramazzina, Ileana; Tappi, Silvia; Rocculi, Pietro; Sacchetti, Giampiero; Berardinelli, Annachiara; Marseglia, Angela; Rizzi, Federica

    2016-10-06

    The atmospheric double barrier discharge (DBD) plasma technology is a promising tool in food industry as an alternative to traditional food preservation methods. However, the effect of the reactive chemical species generated during the treatment on the qualitative and quantitative content of bioactive compounds in food is still little studied, as well as there are no data concerning potential deleterious effects of DBD treated foods on human cells. We measured antioxidants content and antioxidant capacity of DBD-treated minimally processed Pink Lady® apples in comparison with untreated matched samples. Moreover, we compared the effects of polyphenols extracts obtained from DBD-treated apples on cell viability, reactive oxygen species production and phase II enzyme activation. The results show that the plasma treatment causes a slight reduction of antioxidant content and antioxidant capacity. Noteworthy, apple treated polyphenols extracts do not reduce cell viability and do not suppress the beneficial physiological cell response to oxidative stress.

  20. Evaluating nitrogen utilization efficiency of nonpregnant dry cows offered solely fresh cut grass at maintenance levels.

    Science.gov (United States)

    Stergiadis, S; Chen, X J; Allen, M; Wills, D; Yan, T

    2015-02-01

    The present study aimed to identify key parameters influencing N utilization and develop prediction equations for manure N output (MN), feces N output (FN), and urine N output (UN). Data were obtained under a series of digestibility trials with nonpregnant dry cows fed fresh grass at maintenance level. Grass was cut from 8 different ryegrass swards measured from early to late maturity in 2007 and 2008 (2 primary growth, 3 first regrowth, and 3 second regrowth) and from 2 primary growth early maturity swards in 2009. Each grass was offered to a group of 4 cows and 2 groups were used in each of the 8 swards in 2007 and 2008 for daily measurements over 6 wk; the first group (first 3 wk) and the second group (last 3 wk) assessed early and late maturity grass, respectively. Average values of continuous 3-d data of N intake (NI) and output for individual cows ( = 464) and grass nutrient contents ( = 116) were used in the statistical analysis. Grass N content was positively related to GE and ME contents but negatively related to grass water-soluble carbohydrates (WSC), NDF, and ADF contents ( grass WSC contents and ratios of N:WSC, N:digestible OM in total DM (DOMD), and N:ME ( grass N contents and lower grass WSC, NDF, ADF, DOMD, and ME concentrations were significantly associated with greater MN, FN, and UN ( grass lower in N and greater in fermentable energy in animals fed solely fresh grass at maintenance level can improve N utilization, reduce N outputs, and shift part of N excretion toward feces rather than urine. These outcomes are highly desirable in mitigation strategies to reduce nitrous oxide emissions from livestock. Equations predicting N output from BW and grass N content explained a similar amount of variability as using NI and grass chemical composition (excluding DOMD and ME), implying that parameters easily measurable in practice could be used for estimating N outputs. In a research environment, where grass DOMD and ME are likely to be available, their use to predict N outputs is highly recommended because they strongly improved of the equations in the current study.

  1. Effects of storage temperature and fruit ripening on firmness of fresh cut tomatoes

    NARCIS (Netherlands)

    Moreira Lana, M.; Tijskens, L.M.M.; Kooten, van O.

    2005-01-01

    Tomato fruit (cultivar Belissimo) were harvested at three different stages of ripening, sliced and stored at at 2, 5, 8, 12 and 16 °C. Firmness was measured as the force necessary to cause a deformation of 3 mm, in the outer and the radial pericarp, daily or every two days, depending on the combinat

  2. Mechanical Stress Results in Immediate Accumulation of Glucosinolates in Fresh-Cut Cabbage

    National Research Council Canada - National Science Library

    Požrl, Tomaž; Cigić, Blaž; Demšar, Lea; Hribar, Janez; Polak, Tomaž

    2015-01-01

    The intensity of mechanical stress and the temperature significantly affect the levels of individual and total glucosinolates in shredded white cabbage (cv. Galaxy). Mild processing (shredding to 2 mm thickness) at 8...

  3. Assessment of changes in optical properties of fresh-cut tomato using video image analysis

    NARCIS (Netherlands)

    Moreira Lana, M.; Tijskens, L.M.M.; Theije, A.; Hogenkamp, M.; Kooten, van O.

    2006-01-01

    Tomato fruit (Lycopersicon esculentum cv. Belissimo) at different stages of maturity were sliced in 7-mm thick transverse slices and stored at 5 °C. In a second experiment, slices obtained from fruit at the light-red stage were stored at temperatures from 5 to 13 °C. Intact control fruit were stored

  4. The pink eye syndrome does not impair tuber fresh cut wound-related responses

    Science.gov (United States)

    The potato tuber pink eye (PE) syndrome is a costly physiological disorder that results in corruption of the native periderm, susceptibility to infection, water vapor loss and associated shrinkage, roughened and cracked tuber surfaces, and various related blemishes and defects. PE results in aberra...

  5. Mechanical Stress Results in Immediate Accumulation of Glucosinolates in Fresh-Cut Cabbage

    Directory of Open Access Journals (Sweden)

    Tomaž Požrl

    2015-01-01

    Full Text Available The intensity of mechanical stress and the temperature significantly affect the levels of individual and total glucosinolates in shredded white cabbage (cv. Galaxy. Mild processing (shredding to 2 mm thickness at 8°C resulted in the accumulation of glucosinolates (40% increase in comparison with unshredded cabbage, which was already seen 5 min after the mechanical stress. Severe processing (shredding to 0.5 mm thickness at 20°C, however, resulted in an initial 50% decrease in glucosinolates. The glucosinolates accumulated in all of the cabbage samples 30 min from processing, resulting in higher levels than in unshredded cabbage, except for the severe processing at 20°C where the increase was not sufficient to compensate for the initial loss. Glucobrassicin and neoglucobrassicin were the major glucosinolates identified in the cabbage samples. Mechanical stress resulted in an increase in the relative proportion of glucobrassicin and in a decrease in neoglucobrassicin.

  6. The application of high-concentration short-time chlorine dioxide treatment for selected specialty crops including Roma tomatoes (Lycopersicon esculentum), cantaloupes (Cucumis melo ssp. melo var. cantaloupensis) and strawberries (Fragaria×ananassa).

    Science.gov (United States)

    Trinetta, V; Linton, R H; Morgan, M T

    2013-06-01

    The effects of high-concentration short-time chlorine dioxide (ClO2) gas treatment on food-borne pathogens inoculated onto the surface of tomatoes, cantaloupes, and strawberries were studied. Produce were spot-inoculated with a mixture of Salmonella enterica (serotypes Montevideo, Javiana and Baildon), Escherichia coli O157:H7 (serotypes 204 P, EDL 933 and C792) or Listeria monocytogenes (serotypes Scott A, F 5069 and LCDC 81-861), and treated with ClO2 gas at 10 mg/l for 180 s. After ClO2 gas treatment, surviving populations were determined and shelf-life studies were conducted (microbial spoilage population, change in color and overall appearance). Significant microbial reduction (p 0.05). Results obtained suggest the potential use of high-concentration short-time ClO2 gas treatment as an effective online pathogen inactivation technology for specialty crops in large-scale produce packing operations.

  7. Symptoms and Sensitivity to Chilling Injury of Cantaloupe Melons during Postharvest Síntomas y Sensibilidad a Daño por Enfriamiento de Melones Reticulados durante Poscosecha

    Directory of Open Access Journals (Sweden)

    Christian Krarup

    2009-06-01

    Full Text Available The nature and development of specific symptoms of chilling injury (CI and the variation in sensitivity to the disorder of different cultivars of cantaloupe melons (Cucumis melo L. subsp. melo var. cantalupensis Naudin was assessed during two seasons. Twenty-three cultivars of the Eastern Shipper (2, Western Shipper (13 and Galia (8 types were grown in a semiarid environment in Curacaví (33º27’ S, 70º38’ W, Chile, using common cultural practices. Fruits were harvested at the half-slip stage, except Galia (3/5 color, graded ,washed, and stored for 18 days at 0 ºC, with an additional 3 days at 20 ºC. Symptoms of CI appeared with varying intensity in almost all cultivars and were generally similar. Symptoms developed progressively: surface discoloration progressed from light pink to brownish to black, followed by large sunken areas, and eventually, discrete indentations and net whitening. Surface decay was not present in most fruits and should be considered a consequence rather than a symptom of CI. Cultivars had different sensitivities to the disorder; some cultivars were severely injured (Athena, Colima and Revigal whereas others developed almost no symptoms of CI (Hy-Mark, Gal 96, and Voyager I. The response variability to chilling showed the need for precise temperature recommendations for these cultivars, and signaled a potential for future long-term transport or storage of some cultivars.La naturaleza y el desarrollo de los síntomas de daño por enfriamiento (CI y la variación en sensibilidad de diversos cultivares de melones reticulados (Cucumis melo L. subsp. melo var. cantalupensis Naudin a este desorden fisiológico se evaluaron durante dos temporadas. Veintitrés cultivares de los tipos Eastern (1, Western (15 y Galia (8 se cultivaron en un ambiente semi-árido en Curacaví (33º27’ S, 70º38’ O, Chile, en cultivos realizados de manera convencional, y los frutos se cosecharon al estado de madurez de medio desprendimiento

  8. Características de frutos do meloeiro variando número e posição de frutos na planta Yield and quality of muskmelon varying fruit number and position in the plant, in protected cultivation

    Directory of Open Access Journals (Sweden)

    Roberto Cleiton F de Queiroga

    2009-03-01

    Full Text Available O trabalho foi conduzido em ambiente protegido, em área experimental da Universidade Federal de Viçosa, de 26/09/05 a 24/01/06, onde se objetivou avaliar a produtividade e a qualidade de frutos do meloeiro, variando número e posição de frutos na planta. Os tratamentos constaram de número de frutos por planta (1 e 2 e posição de fixação de frutos na planta (entre 5(0 e 8(0 nós e 15(0 e 18(0 nós. O delineamento experimental utilizado foi de blocos ao acaso no esquema fatorial 2 x 2, com 5 repetições. Utilizou-se a 'Coronado F1', variedade reticulatus do grupo Cantaloupe, cultivada em vasos plásticos de 11,5 dm³ preenchidos com fibra de coco comercial. Plantas com um fruto apresentaram maior duração do período de colheita, área foliar (AF (5(0 - 8(0 nó, massa média de frutos (MMF, reticulação da casca (RC, espessura da polpa (EP, comprimento (CF e diâmetro de frutos (DF, sólidos solúveis totais (SST, açúcares solúveis totais (AST, açúcares não redutores (ANR e menor produtividade comercial (PCF. A condução com frutos fixados entre os 15(0 e 18(0 nós, comparado a frutos fixados entre os 5(0 e 8(0 nós, proporcionou maior número de dias para iniciar e terminar a colheita, AF, MMF, PCF, EP, CF e DF (em plantas com 1 fruto, índice de maturação, AST, ANR e menor RC, acidez total titulável e concentração de açúcares redutores.The study was carried out in a greenhouse of the Universidade Federal de Viçosa, Minas Gerais State, Brazil, from 26/09/05 to 24/01/06, to evaluate the yield and quality of the melon fruit, varying the number and position of fruits on the plant. The treatments consisted of fruit number per plant (1 and 2 and fruit position in the plant (5th - 8th node and 15th - 18th node. A randomized block design was used, in a 2 x 2 factorial scheme, with 5 replications. The 'Coronado F1', variety reticulatus of the Cantaloupe group was cultivated in 11.5 dm³ plastic pots with commercial coconut

  9. 甜瓜蔗糖合成酶基因(CmSS1)反义表达载体的构建及遗传转化%Construction of CmSS1 Antisense Expression Vector and Its Transformation into Muskmelon

    Institute of Scientific and Technical Information of China (English)

    闻小霞; 赵荷仙; 刘刚; 周爱凤; 张桂梅

    2013-01-01

    以BamH Ⅰ和SalⅠ双酶切pMD18-T-CmSS1和表达载体pBI121,再用T4 DNA连接酶将回收的目的片段反向与pBI121连接.结果证明,CmSS1反向插入到pBI121中,得到了pBI121-CmSS1的重组质粒;利用农杆菌介导法将反义CmSS1基因转化甜瓜,经PCR检测,得到5株转基因植株.这为以后研究甜瓜蔗糖合成酶的活性调节机制及通过基因工程手段研究甜瓜SS的活性奠定了基础.%The pMD18 - T - CmSSl and the expression vector pBI121 were digested respectively with Bam H I and Sal I , and then the target fragments were connected by T4 DNA ligase. The results showed that the CmSSl gene was successfully inserted into the plant expression vector pBI121 and the antisense expression vector pBI121 - CmSSl was obtained. The anti - CmSSl was transformed to muskmelon by Agrobacterium -mediated, and five transgenic plants were obtained by PCR detection. This research laid foundations for further research of regulation mechanisms of muskmelon SS activity by genetic engineering.

  10. Avaliação de fontes de cálcio na cultura do melão tipo 'Gália' sob cultivo protegido Comparative analysis of calcium sources in greenhouse 'Galia' muskmelon

    Directory of Open Access Journals (Sweden)

    Eva Cintra D. de Faria

    2004-09-01

    álcio quelatizado.'Galia' muskmelons, Galileo hybrid, were grown at Embrapa Hortaliças in Brasilia, Brazil, in a greenhouse in pots, from September to December 2001. Five calcium treatments were evaluated (liming and liming plus fertigation with calcium nitrate, calcium buffered, calcium chelates and calcium chloride, besides the control without calcium (Ca. The experimental design was of randomized blocks with 6 treatments, 4 replications and 6 plants per plot. Overall calcium application increased marketable yield (kg m-2 by 26% and the number of fruits by 21%. These results indicated the need of Ca fertilization in soils with base saturation lower than 70%. Liming plus calcium fertigation increased yield and the number of marketable fruits by 30% and 27%, respectively. Thus, Ca fertigation was more effective than liming. Fertigation with calcium nitrate and calcium chloride presented the highest profitability. No effect was observed on the average fruit weight. No significant effects on treatments were obtained for pulp thickness, soluble solids content (Brix, total titratable acidity (TTA and Brix/TTA ratio. In conclusion, Ca must be applied to greenhouse muskmelon for soils with base saturation lower than 70%. Liming plus Ca fertigation was more profitable than only liming. Fertigation of Ca-nitrate or Ca-chloride was more profitable than liming plus Ca treatments (liming and liming plus fertigation with Ca-buffered or Ca-chelates.

  11. Formas de aplicação de cálcio na cultura do melão rendilhado sob cultivo protegido Calcium application methods on greenhouse muskmelon cultivation

    Directory of Open Access Journals (Sweden)

    Eva Cintra Duarte de Faria

    2004-06-01

    Full Text Available Um experimento foi conduzido na área experimental da Embrapa Hortaliças, em Brasília, de abril a agosto de 2001, para avaliar o efeito das formas de aplicação de cálcio na produção de melão (Cucumis melo L. var. reticulatus, tipo gália, híbrido Galileo, sob cultivo protegido. O delineamento experimental utilizado foi blocos ao acaso, com seis tratamentos e quatro repetições. Foram cinco tratamentos com cálcio: calagem e fertirrigação com nitrato de cálcio, nas doses de 30; 80; 130; 180 kg ha-1 de Ca e a testemunha sem cálcio. A aplicação de Ca aumentou em 35% a produção comercial e o número de frutos em 27% em relação a testemunha. Estes resultados sugerem que, mesmo em solos com relativamente alto teor de cálcio, há necessidade de aplicação desse nutriente em pré-plantio ou em fertirrigação. As médias dos tratamentos fertirrigados com cálcio (4,71 kg m-2 não diferiram (p>0,05 da calagem (4,19 kg m-2, demonstrando assim que o fornecimento de cálcio às plantas em fertirrigação foi tão eficiente quanto a calagem. A produção máxima de 5,1 kg m-2 foi obtida com a aplicação de 115 kg ha-1 de Ca. Os tratamentos fertirrigados com nitrato de cálcio nas doses de 130 e 80 kg ha-1 de Ca apresentaram maior rentabilidade. Não houve efeito dos tratamentos sobre o peso médio do fruto e concentração de nutrientes nas folhas do meloeiro.An experiment was carried out at Embrapa Hortaliças in Brasília, Brazil, from April to August 2001 to evaluate calcium application methods on muskmelon (Cucumis melo var. reticulatus, hybrid Galileo, Galia type, on greenhouse cultivation. The experimental design was of randomized blocks, with six treatments and four replications. There were five calcium applications: liming and 30; 80; 130; 180 kg ha-1 Ca rates in fertigation with calcium nitrate and a control treatment with no Ca. The calcium application increased the marketable yield by 35% and the number of fruits by 27

  12. Curva crítica de diluição do nitrogênio para a cultura do melão Nitrogen critical dilution curve for the muskmelon crop

    Directory of Open Access Journals (Sweden)

    Marco Aurélio de Freitas Fogaça

    2008-04-01

    Full Text Available O objetivo do trabalho foi ajustar a curva crítica de diluição do nitrogênio da cultura do melão. O experimento foi conduzido em ambiente protegido na Universidade Federal de Santa Maria (UFSM, entre agosto de 2004 e janeiro de 2005. As mudas do híbrido Magellan foram plantadas em sacolas de polietileno contendo 4,5dm-3 de substrato comercial (Plantmax PXT®, na densidade de 3,3 plantas m-2 e fertirrigadas com solução nutritiva completa. As plantas foram conduzidas verticalmente com uma haste, deixando-se no máximo dois frutos por planta e foram podadas ao atingir a altura de 2m. Os tratamentos foram constituídos por concentrações de nitrogênio na solução nutritiva de 8; 11, 14; 17 e 20mmol L-1. O delineamento experimental utilizado foi o inteiramente casualizado com quatro repetições. Quatro plantas de cada tratamento foram coletadas semanalmente entre os 33 e 99 dias após o plantio para determinar o acúmulo de matéria seca (MS e o teor de N nas folhas, haste e frutos. Foi constatada a diluição da concentração de N na matéria seca em todos os tratamentos e os dados ajustaram-se ao modelo potencial %N = aMS-b descrito na literatura. A curva crítica de diluição do N foi ajustada, com coeficientes a e b iguais a 5,16 e 0,63, respectivamente. Esse modelo poderá ser usado para estimar a quantidade de N extraída no decorrer do ciclo de crescimento e desenvolvimento dessa cultura, com base na análise do teor desse nutriente nas folhas.The research was carried out to adjust the nitrogen critical dilution curve for the muskmelon crop, to be used in fertilization practices for this crop. The experiment was conducted in a greenhouse at Universidade Federal de Santa Maria, from August to January, 2005. Plantlets of the hybrid Magellan was grown in polyethylene bags with 4.5dm3 of the commercial substrate Plantmax PXT®, in a plant density of 3.3plants m-2, and fertigated with a complete nutrient solution. Plants were

  13. Conservação pós-colheita de melões Galia 'Solar King' tratados com 1-metilciclopropreno Postharvest storage of Galia 'Solar King' muskmelon treated with 1-methylcyclopropene

    Directory of Open Access Journals (Sweden)

    Maria Auxiliadora C. de Lima

    2004-03-01

    Full Text Available Avaliou-se o efeito de concentrações de 1-metilciclopropeno (1-MCP sobre o amaciamento da polpa (através da firmeza e de tomografia de ressonância magnética, o desenvolvimento da região de abscisão do pedúnculo, o comportamento respiratório e a qualidade pós-colheita de melão Galia 'Solar King', em temperatura ambiente. Os frutos, provenientes do Polo Agrícola Mossoró-Assú (RN, foram colhidos com a região do pedúnculo ainda íntegra e tratados com solução contendo o fungicida Imazalil e a cera Megh Wash, ambos na concentração de 20 ml 10 L-1. Os frutos foram submetidos a tratamento com 1-MCP, nas concentrações 0; 100; 300 e 900 nl L-1, e ao armazenamento sob temperatura ambiente (24,5 ± 0,9ºC e 86,4 ± 7,9% UR, durante 0; 4; 8; 12; 16 e 20 dias. Utilizou-se o delineamento experimental inteiramente casualizado, em esquema fatorial 4x6, com quatro repetições. O 1-MCP reduziu a atividade respiratória, atrasou o pico de produção de etileno e retardou a evolução do amaciamento da polpa e o desenvolvimento da região de abscisão do pedúnculo. Não foram verificados efeitos das concentrações testadas sobre a perda de massa, a acidez total titulável, o pH, o teor de sólidos solúveis totais, o teor de açúcares solúveis totais e a aparência externa. Contudo, a aparência interna dos frutos tratados foi melhor, principalmente naqueles expostos a 300 nl L-1. Esta concentração possibilitou, ainda, atividade respiratória mais baixa, frutos mais firmes e com menor desenvolvimento da região de abscisão peduncular.The effect of 1-methylcyclopropene (doses of 1-MCP on pulp softening (through firmness and magnetic resonance imaging, development of the stalk abscission layer, respiratory behavior and postharvest quality of Galia 'Solar King' muskmelon was evaluated. Fruits from the Mossoró-Assú Agricultural Region in Rio Grande do Norte State, Brazil, were harvested when the stalk area was intact and treated with a

  14. Produtividade e qualidade do melão cantaloupe, cultivado em ambiente protegido, variando o número e a posição dos frutos na planta Fruit yield and quality of cantaloupe melon, under greenhouse conditions, as affected by number of fruits and position in the plant

    Directory of Open Access Journals (Sweden)

    Roberto Cleiton Fernandes de Queiroga

    2008-12-01

    Full Text Available Os frutos do meloeiro são considerados fortes drenos que alteram a distribuição de fotoassimilados entre os órgãos da planta. Objetivou-se nesse trabalho determinar a produção e a qualidade de frutos de meloeiro em ambiente protegido em função do número e da posição de fixação dos frutos na planta. O experimento foi desenvolvido em fatorial 2 x 2 em blocos ao acaso, com cinco repetições, provenientes da combinação de número de frutos por planta (1 e 2 e posição de fixação dos frutos na planta (entre 5.º e 8.° nós e entre 15.° e 18.° nós. O melão cultivar 'Torreon', do grupo Cantalupensis, foi plantado em vasos de 11,5 dm³ contendo como substrato apenas fibra de coco adubada com macro e micronutrientes. Comparado a plantas com dois frutos, nas plantas com apenas um fruto ocorreram os maiores valores de: massa dos frutos (MF, reticulação da casca (RC, comprimento, índice de formato, espessura da polpa, índice de maturação (IM, sólidos solúveis (SS, açúcares solúveis totais, açúcares não redutores. Em plantas com apenas um fruto, ocorreu redução na produtividade comercial (PC de 21,4% em frutos fixados especificamente entre o 5.° e 8.° nós e 24,9% em frutos do 15.° e 18.° nós comparada a plantas com dois frutos. Em frutos fixados na posição do 15.° e 18.° nós ocorreram maiores MF, IM, PC e ciclo da cultura, bem como, menores RC e acidez total titulável. Foram obtidas correlações significativas para área foliar por fruto (AF x MF de 0,81, AF x SS de 0,79, MF x SS de 0,68, MF x RC de 0,72 e RC x SS de 0,51.Muskmelon fruits are strong sink affecting assimilate distribution among the plant organs. This experiment aimed at to determine yield and quality of 'Torreon' cultivar in greenhouse conditions as affected by fruit number and position in the plant. A 2 x 2 factorial was set in randomized block design, with five replications. Treatments combined fruit number per plant (1 and 2 and

  15. Cloning of Phytoene Synthase Gene from Muskmelon and Construction of Its Sense Expression Vector%甜瓜果实八氢番茄红素合成酶基因的克隆及正义表达载体的构建

    Institute of Scientific and Technical Information of China (English)

    马乐园; 于喜艳

    2011-01-01

    根据GenBank中登记的甜瓜八氢番茄红素合成酶(CmPSY)基因序列设计引物,利用RT - PCR技术克隆了甜瓜PSY全长基因,该基因全长1 443 bp,编码421个氨基酸,在GenBank中登记号为GU361622.以BamH Ⅰ和SalⅠ双酶切pMD18 -T - CmPSY和表达载体pBI121,再将回收的目的片段与pBI121用T4 DNA 连接酶连接,结果证明,CmPSY正向插入到pBI121中,得到了pBI121- CmPSY的重组质粒.该研究为了解甜瓜八氢番茄红素合成酶的活性调节机制,并通过基因工程手段研究甜瓜PSY的活性奠定了基础.%According to the registered muskmelon phytoene synthase (CmPSY) gene sequences in GenBank with the accession number of GU361622, the primers were designed to clone the full length of CmPSY by RT - PCR. The results showed that its full - length cDNA sequence was 1 443 bp encoding 421 amino acids. The pMD18 - T - CmPSY and the expression vector pBI121 were digested respectively with BamH I and Sal I and then were connected by T4 DNA ligase. The results showed that the CmPSY gene was successfully inserted into the plant expression vector pBI121 and the sense expression vector pBI121 - CmPSY was obtained. This research laid the foundation for research on the regulation mechanisms of muskmelon PSY activity by genetic engineering.

  16. Relationship between Sugar Accumulation and Its Metabolizing Enzymes during Muskmelon Fruit Development%河套蜜瓜果实发育过程中糖积累与蔗糖代谢相关酶的关系

    Institute of Scientific and Technical Information of China (English)

    张中霞; 刘艳; 白立华; 蔡贵芳

    2011-01-01

    以河套蜜瓜为试材,采用外部形态观测与内部生理指标测定相结合的方法,对其果实发育过程中果实生长模式以及果实中蔗糖、果糖、葡萄糖和淀粉含量以及蔗糖代谢相关酶活性进行测定,以揭示河套蜜瓜果实生长发育过程中糖的代谢积累与相关酶的关系.结果显示:(1)河套蜜瓜果实生长速率呈单"S"曲线,果实发育早期以积累葡萄糖为主,进入成熟期后蔗糖积累量迅速增加,最终由蔗糖和己糖共同构成果实品质.(2)在河套蜜瓜果实成熟期前,蔗糖磷酸合成酶(SPS)活性维持较低水平,进入成熟期后,SPS活性迅速升高;蔗糖合成酶(SS)活性在成熟期前为分解活性大于合成活性,成熟期后表现为合成活性大于分解活性;在整个果实发育期,酸性转化酶(AI)活性较低,中性转化酶(NI)活性始终高于AI.(3)在果实整个发育期,蔗糖含量与蔗糖代谢酶的净活力呈极显著正相关,蔗糖代谢相关酶共同作用决定果实中蔗糖含量.研究表明,在河套蜜瓜果实发育前期,以蔗糖分解代谢为主,且蔗糖合成酶和中性转化酶是催化蔗糖分解的关键酶;果实成熟期间,蔗糖代谢转为合成方向为主,蔗糖合成酶和蔗糖磷酸合成酶在蔗糖积累中起主导作用.%The changes of growth phase, sucrose, glucose, fructose, starch and the activities of sugar metabolism-related enzymes in Muskmelon fruit development (Cucumis melo L. cv. Hetao) were determined to study the relationship between the sugar accumulation and its metabolizing enzymes in Hetao. The results indicated that:(1)the growth curves of Hetao showed single sigmoid pattern; The fruit of Hetao mainly accumulated glucose in the early stage;sucrose accumulated rapidly in mature period,finally accumulation of sucrose and sugar together constituted the fruit quality. (2)The activity of sucrose phosphate synthase (SPS) was low before mature period,the activity of SPS increased rapidly

  17. Characterisation of volatile profile and sensory analysis of fresh-cut "Radicchio di Chioggia" stored in air or modified atmosphere.

    Science.gov (United States)

    Cozzolino, Rosaria; Martignetti, Antonella; Pellicano, Mario Paolo; Stocchero, Matteo; Cefola, Maria; Pace, Bernardo; De Giulio, Beatrice

    2016-02-01

    The volatile profile of two hybrids of "Radicchio di Chioggia", Corelli and Botticelli, stored in air or passive modified atmosphere (MAP) during 12 days of cold storage, was monitored by solid phase micro-extraction (SPME) GC-MS. Botticelli samples were also subjected to sensory analysis. Totally, 61 volatile organic compounds (VOCs) were identified in the headspace of radicchio samples. Principal component analysis (PCA) showed that fresh product possessed a metabolic content similar to that of the MAP samples after 5 and 8 days of storage. Projection to latent structures by partial least squares (PLS) regression analysis showed the volatiles content of the samples varied depending only on the packaging conditions. Specifically, 12 metabolites describing the time evolution and explaining the effects of the different storage conditions were highlighted. Finally, a PCA analysis revealed that VOCs profile significantly correlated with sensory attributes.

  18. Storage of intact heads prior to processing limits the shelf-life of fresh-cut Lactuca sativa L.

    NARCIS (Netherlands)

    Witkowska, I.M.; Woltering, E.J.

    2014-01-01

    Harvested lettuce heads are usually transported and stored for some period of time under a variety of conditions prior to processing. During storage, especially under suboptimal conditions, nutritional composition of the harvested produce continues to change. The possible impact of prior storage of

  19. Effect of Ozone and Calcium Lactate Treaments on Browning and Textured Properties of Fresh-Cut Lettuce.

    OpenAIRE

    Rico, Daniel; Martin-Diana, Ana Belen; Henehan, Gary; Frias, Jesus Maria; Barat, J.; Barry-Ryan, Catherine

    2007-01-01

    The preservation of quality of fresh products is relevant for the industry due to its economic impact. This paper presents a comprehensive review of the use of different sources of calcium to preserve fresh fruits and vegetables in order to extend the shelf life and enhance the nutritional value. Emphasis is on discussing about the best sources of calcium, concentration, temperature and method of application, suitability of the commodities; and some hints for the cost/benefit analysis are pre...

  20. Quality of fresh-cut 'Kent' mango slices prepared from hot water or non hot water treated fruit

    Science.gov (United States)

    A quarantine heat treatment consisting of exposure to 46°C water for 65 to 110 minutes (depending on cultivar and fruit size) is mandated by USDA-APHIS for all mangoes (Mangifera indica L.) entering the United States. Heat treatments may affect ripening processes and induce resistance to chilling in...

  1. Enhancing safety and shelf life of fresh-cut mango by application of edible coatings and microencapsulation technique.

    Science.gov (United States)

    Alikhani, Majid

    2014-05-01

    Mango pulp is very perishable and so has a short shelf life, which both marketers and consumers would like to be longer. Manually sliced mango was treated by coating opuntia mucilage-rosemary oil (Mu + RO), 2 g rosemary oil microencapsul (ROM), and 2 g (ROM) plus (Mu + RO); the treated mango pieces were placed in plastic trays, and overwrapped with PVDC film and then stored at 6°C. Changes in the quality parameters and activity of peroxidase (POD) enzyme were evaluated for 9 days of storage period. These treatments retarded loss of ascorbic acid and the drop in sensory acceptability, fewer changes in color, decreasing activity POD enzyme. These also inhibited the decay incidence and slowed microbial growth. The (Mu + RO) treatment was more effective in controlling postharvest quality as compared to the (ROM) treatment, but the data reveal that applying the compound treatment effectively prolongs the quality attributes and extends the storage life of sliced mango fruit.

  2. Predictive modelling for packaging design: equilibrium modified atmosphere packages of fresh-cut vegetables subjected to a simulated distribution chain.

    Science.gov (United States)

    Jacxsens, L; Devlieghere, F; Debevere, J

    2002-03-01

    The impact of temperature fluctuations in a simulated cold distribution chain, typical of commercial practice, was investigated on both the microbial and sensorial quality of equilibrium modified atmosphere (EMA) packaged minimally processed vegetables. The internal O2 concentration of the designed packages could be predicted for the different steps of the simulated distribution chain by applying an integrated mathematical system. The internal atmosphere in the packages remained in its aerobic range during storage in the chain due to the application of high permeable packaging films for O2 and CO2. Spoilage microorganisms were proliferating fast on minimally processed bell peppers and lettuce. Yeasts showed to be the shelf-life limiting group. Visual properties limited the sensorial shelf-life. Listeria monocytogenes was able to multiply on cucumber slices, survived on minimally processed lettuce and decreased in number on bell peppers due to the combination of low pH and refrigeration. Aeromonas caviae was multiplying on both cucumber slices and mixed lettuce, but was as well inhibited by the low pH of bell peppers. Storage temperature control was found to be of paramount importance for the microbial (spoilage and safety) and sensorial quality evaluation of EMA-packaged minimally processed vegetables.

  3. 采前乙酰水杨酸与采后1-MCP处理对厚皮甜瓜冷藏品质及抗氧化能力的影响%Effect of Preharvest Acetylsalicylic Acid and Postharvest 1-MCP Treatments on Quality and Antioxidant Ability of Muskmelon Fruit during Cool Storage

    Institute of Scientific and Technical Information of China (English)

    尚琪; 王婷; 李欣; 刘耀娜; 白晓东; 张溪桐; 王毅; 毕阳

    2016-01-01

    以“玛瑙”厚皮甜瓜为试材,通过采前分别在幼果期(花后2周)、膨大期(花后3周)、网纹形成期(花后4周)和采前2 d 4个时期喷洒乙酰水杨酸和采后1-甲基环丙烯(1-methylcyclopropene,1-MCP)熏蒸,研究单独或复合处理对冷藏期间果实品质及抗氧化能力的影响。结果表明,采前乙酰水杨酸处理可有效抑制贮藏期间果实的质量损失率的增加,延缓果皮转黄,维持可溶性固形物和可滴定酸含量,提高总酚和类黄酮含量,提高抗氧化能力。1-MCP熏蒸能减少果实采后质量损失,维持硬度,增加抗坏血酸含量。复合处理在维持果实可溶性固形物和可滴定酸含量、提高总酚和类黄酮的含量方面表现出协同效应。由此表明,乙酰水杨酸和1-MCP处理对维持甜瓜果实采后品质的作用效果与抑制乙烯的产生有关,而果实抗氧化能力的提高则与促进苯丙烷代谢产物及抗坏血酸的积累相关。%This study examined effects of multiple preharvest acetylsalicylic acid (ASA) sprays combined with postharvest 1-methylcyclopropene (1-MCP) fumigation on the quality and antioxidant ability of muskmelon (Cucumis melo cv. Manao) fruit during cool storage. The plants were sprayed with ASA four times, namely at young fruit period (2 weeks after lfowering), fruit enlarging period (3 weeks after lfowering), netting period (4 weeks after lfowering) and 2 days before harvest, respectively. After harvest, the fruits were fumigated with 1-MCP. The results indicated that preharvest ASA treatment inhibited weight loss, retarded peel yellowing, maintained the levels of total soluble solids and titratable acid, increased the contents of total phenolics and lfavonoids, and enhanced the antioxidant ability of fruits. 1-MCP fumigation decreased weight loss, maintained fruit ifrmness and increased the contents of ascorbic acid. Preharvest ASA combined with postharvest 1-MCP

  4. γ-氨基丁酸(GABA)对低氧胁迫下甜瓜幼苗光合作用和叶绿素荧光参数的影响%Effects of γ-aminobutyric acid on the photosynthesis and chlorophyll fluorescence parameters of muskmelon seedlings under hypoxia stress

    Institute of Scientific and Technical Information of China (English)

    夏庆平; 高洪波; 李敬蕊

    2011-01-01

    By the method of hydroponic culture, this paper studied the effects of exogenous γ-aminobutyric acid ( GABA) on the photosynthetic pigment contents, photosynthesis. and chlorophyll fluorescence parameters of muskmelon seedlings under hypoxia stress. Hypoxia stress induced a significant decrease of photosynthetic pigment contents, resulting in the decrease of photosynthesis.Applying GABA could significantly increase the photosynthetic pigment contents, net photosynthetic rate (Pn) , stomatal conductance ( Gs ) , intercellular CO2 concentration ( Ci) , carboxylation efficiency ( CE ) . maximal photochemical efficiency of Ps Ⅱ ( Fv/Fm ) , photochemical quenching (qP) , apparent photosynthetic electron transfer rate ( ETR) , and quantum yield of PS Ⅱ electron transport ( ΦPSⅡ ) , and decrease the stomatal limitation value (Ls ) , minimal fluorescence ( F0) ,and non-photochemical quenching ( NPQ) under both hypoxic and normal conditions. The alleviation effect of GABA on photosynthetic characteristics was more obvious under hypoxia stress. However. simultaneously applying GABA and VGB could significantly decrease the alleviation effect of GABA under hypoxia stress.%采用营养液水培方法,研究了低氧胁迫下外源γ-氨基丁酸(GABA)对甜瓜幼苗光合色素含量、光合作用及叶绿素荧光参数的影响.结果表明:低氧胁迫导致甜瓜幼苗光合色素含量显著下降,光合作用降低;外源GABA能显著提高正常通气和低氧胁迫下甜瓜幼苗的光合色素含量、净光合速率、气孔导度、胞间CO2浓度、CO2羧化效率、最大光化学效率、光化学猝灭系数、表观光合电子传递速率和PSⅡ光合电子传递量子效率,而气孔限制值、初始荧光和非光化学猝灭系数显著降低,GABA在低氧胁迫下的提高效果更明显;同时添加GABA和GABA转氨酶抑制剂γ-乙烯基-γ-氨基丁酸(VGB)处理显著降低了低氧胁迫下GABA对甜瓜幼苗光合特性的缓解效果.

  5. Produtividade de frutos do meloeiro sob diferentes níveis de salinidade da água de irrigação, com e sem cobertura do solo Fruit yield of muskmelon plants grown at different levels of salinity of irrigation water, with and without soil covering

    Directory of Open Access Journals (Sweden)

    Marcelo Cleón de C. Silva

    2005-06-01

    Full Text Available No presente estudo avaliou-se o número e a produtividade de frutos de dois híbridos de meloeiro submetidos a diferentes níveis salinos da água de irrigação e cobertura do solo. Utilizou-se um esquema fatorial 3 x 2 x 2 em blocos completos casualizados com quatro repetições. Os fatores foram três níveis de salinidade da água de irrigação, com condutividade elétrica de 1,2 dSm-1; 2,5 dSm-1 e 4,4 dSm-1 respectivamente, dois híbridos, Gold Mine e Trusty, com e sem cobertura de solo por filme de polietileno dupla face preto-prateado. Apenas o híbrido Trusty apresentou redução do número de frutos total em resposta à salinidade da água de irrigação. A produtividade de frutos comerciáveis foi semelhante em ambos os híbridos, reduzindo-se com o aumento da condutividade elétrica. Para a cobertura do solo, os dois híbridos também reagiram de forma diferenciada, com número de frutos total e produtividade mais elevados no híbrido Trusty com solo coberto.The number and the yield of fruits from two hybrid of muskmelon, submitted to different saline levels of irrigation water and soil covering was evaluated. A factorial outline was used 3 x 2 x 2 in a complete randomized blocks design with four replications. The factors were three levels of salinity of irrigation water, with electric conductivity of 1.2 dSm-1; 2.5 dSm-1 and 4.4 dSm-1 respectively, two hybrids, Gold Mine and Trusty, with and without soil covering using black-silvery double face polyethylene film. The hybrids reacted in different ways to the salinity of irrigation water. Reduction on the total number of fruits was observed only in the hybrid Trusty. The marketable yield of fruits was similar in both hybrids, being reduced with the increase of the electric conductivity. For the usage of soil covering the hybrids also reacted in a different way. The hybrid Trusty produced greater number of fruits and higher yield in treatments using soil covering.

  6. The use of lytic bacteriophages to reduce E. coli O157:H7 on fresh cut lettuce introduced through cross-contamination

    Science.gov (United States)

    The role of lytic bacteriophages in preventing cross contamination of produce has not been evaluated. A cocktail of three lytic phages specific for E. coli O157:H7 (EcoShield) at 108 PFU/ml or a control (phosphate buffered saline, PBS) was applied to lettuce by either 1) spraying on to lettuce piec...

  7. Biocontrole de Listeria monocytogenes por Pediococcus acidilactici em couve minimamente processada Biocontrol of Listeria monocytogenes by Pediococcus acidilactici in fresh-cut kale

    Directory of Open Access Journals (Sweden)

    Wanessa Altimiras Costa

    2009-12-01

    Full Text Available Este estudo avaliou um sistema de biocontrole para inibição de Listeria monocytogenes em couve minimamente processada, objetivando sua segurança durante estocagem sob refrigeração e em condições de abuso de temperatura. O potencial inibitório de bactérias láticas tolerantes ao sal e psicrotróficas contaminantes naturais da couve e Lactobacillus plantarum, Lactobacillus delbrueckii ATCC 9649 e Lactobacillus casei CCT 1465 foram avaliadas contra L. monocytogenes. O isolado de couve identificado como P. acidilactici CCA3 inibiu L. monocytogenes a 10 e 15 °C em ágar MRS e foi selecionado como possível agente de biocontrole. O número de L. monocytogenes na couve minimamente processada aumentou 3,7 e 4,7 ciclos logarítmicos a 5 e 10 °C, respectivamente, após 20 dias de armazenamento e 4,6 ciclos logarítmicos após oito dias a 15 °C. Entretanto, quando 10(8 UFC.g-1 de P. acidilactici CCA3 foram inoculados no produto processado, o crescimento de L. monocytogenes reduziu 2,3 ciclos logarítmicos sob temperatura abusiva de 15 °C. A acidez titulável e as características sensoriais da couve não foram alteradas pela presença de CCA3 ao longo do período de vida útil. Estes resultados sugerem o potencial de aplicação dos bioconservantes na couve minimamente processada, que necessitam estar associados à refrigeração e sanitização para garantir segurança.This study evaluated a biological control system for the inhibition of Listeria monocytogenes in minimally processed kale focusing on its freshness under refrigeration and extreme temperatures. The inhibitory potential of salt and cold tolerant lactic bacteria from natural microflora of kale, Lactobacillus delbrueckii ATCC 9649, Lactobacillus plantarum, and Lactobacillus casei CCT 1465 strains were evaluated against L. monocytogenes. Pediococcus acidilactici CCA3 isolated from kale exhibited a large inhibition zone of L. monocytogenes at 10 and 15 °C in MRS agar and was selected as a possible biological control bacterium. The population of L. monocytogenes inoculated in minimally processed kale increased 3.7 and 4.7 logarithmic cycles at 5 and 10 °C, respectively, after 20 days of storage and 4.6 logarithmic cycles at 15 °C after eight days. However, when 10(8 CFU.g-1 of P. acidilactici CCA3 was inoculated into processed product a reduction of L. monocytogenes of 2.3 logarithmic cycles under extreme temperature conditions (15 °C occurred. P. acidilactici CCA3 did not alter the titratable acidity or the kale sensorial characteristics during the shelf life period. These results suggest the potential application of biopreservatives on minimally processed kale that need to be associated with refrigeration and sanitation to assure safety.

  8. Measurement of multiple vitamin K forms in processed and fresh-cut pork products in the U.S. food supply

    Science.gov (United States)

    Vitamin K food composition data have historically been limited to plant-based phylloquinone (vitamin K1). Recent reports from Europe attribute heart health benefits to menaquinones. The purpose of this study was to expand analysis of vitamin K to animal products, and measure phylloquinone and 10 f...

  9. Effects of concentrate crude protein content on nutrient digestibility, energy utilization, and methane emissions in lactating dairy cows fed fresh-cut perennial grass.

    Science.gov (United States)

    Hynes, D N; Stergiadis, S; Gordon, A; Yan, T

    2016-11-01

    Although many studies have investigated mitigation strategies for methane (CH4) output from dairy cows fed a wide variety of diets, research on the effects of concentrate crude protein (CP) content on CH4 emissions from dairy cows offered fresh grass is limited. The present study was designed to evaluate the effects of cow genotype and concentrate CP level on nutrient digestibility, energy utilization, and CH4 emissions in dairy cows offered fresh-grass diets. Twelve multiparous lactating dairy cows (6 Holstein and 6 Holstein × Swedish Red) were blocked into 3 groups for each breed and assigned to a low-, medium-, or high-CP concentrate diet [14.1, 16.1, and 18.1% CP on a dry matter (DM) basis, respectively], in a 3-period changeover study (25d per period). Total diets contained (DM basis) 32.8% concentrates and 67.2% perennial ryegrass, which was harvested daily. All measurements were undertaken during the final 6d of each period: digestibility measurements for 6d and calorimetric measurements in respiration chambers for 3d. Feed intake and milk production data were reported in a previous paper. We observed no significant interaction between concentrate CP level and cow genotype on any parameter. Concentrate CP level had no significant effect on any energy utilization parameter, except for urinary energy output, which was positively related to concentrate CP level. Similarly, concentrate CP content had no effect on CH4 emission (g/d), CH4 per kg feed intake, or nutrient digestibility. Cross breeding of Holstein cows significantly reduced gross energy, digestible energy, and metabolizable energy intake, heat production, and milk energy output. However, cow genotype had no significant effect on energy utilization efficiency or CH4 parameters. Furthermore, the present study yielded a value for gross energy lost as CH4 (5.6%) on fresh grass-based diets that was lower than the widely accepted value of 6.5%. The present findings indicate that reducing concentrate CP content from 18.1 to 14.1% may not be a successful way of alleviating CH4 emissions from lactating dairy cows offered good-quality fresh grass, but grazing cows could be offered a low-CP concentrate without compromising energy utilization efficiency. Further research is needed to investigate whether larger differences in dietary CP content may yield positive results.

  10. Effectiveness of lytic bacteriophages in reducing E. coli O157:H7 populations introduced through cross-contamination on fresh cut lettuce

    Science.gov (United States)

    Previous research has shown that lytic bacteriophages (phages) can kill E. coli O157:H7 on produce surfaces. The role of lytic bacteriophages in preventing cross contamination of produce has not been evaluated. A cocktail of three lytic phages specific for E. coli O157:H7 (EcoShield) at 10^8 PFU/m...

  11. 鲜切莲藕酶褐变的控制方法%Study on Inhibiting Enzymatic Browning in Fresh- Cut Lotus Roots

    Institute of Scientific and Technical Information of China (English)

    张京芳

    2005-01-01

    通过单元抑制剂和多元复合抑制剂对鲜切莲藕多酚氧化酶和褐变度的影响研究表明:单元抑制剂L-半胱氨酸、抗坏血酸和柠檬酸均能降低PPO活性和抑制酶褐变;多元复合抑制剂0.3%AA+0.1%CA+0.4%L-Cys也能有效控制鲜切莲藕的酶褐变,且多元复合抑制剂的作用比单元抑制剂效果更佳.

  12. Dual-species biofilms formation by Escherichia coli O157:H7 and environmental bacteria isolated from fresh-cut processing plants

    Science.gov (United States)

    Biofilm formation is a mechanism adapted by many microorganisms that enhances the survival in stressful environments. In food processing facilities, bacterial strains with strong biofilm forming capacities are more likely to survive the daily cleaning and disinfection. Foodborne bacterial pathogens,...

  13. Effects of storage temperature and stage of ripening on RGB colour aspects of fresh-cut tomato using video image analysis

    NARCIS (Netherlands)

    Moreira Lana, M.; Tijskens, L.M.M.; Kooten, van O.

    2006-01-01

    Tomato fruit (Lycopersicon esculentum cv. Belissimo) were harvested at three different stages of ripening, sliced and stored at five different temperatures. Red-green-blue (RGB) images of the slices were taken regularly during storage, using a image processing system. For constructing a model, each

  14. Fate of Escherichia coli O157:H7 on Fresh-Cut Apple Tissue and Its Potential for Transmission by Fruit Flies

    Science.gov (United States)

    Janisiewicz, W. J.; Conway, W. S.; Brown, M. W.; Sapers, G. M.; Fratamico, P.; Buchanan, R. L.

    1999-01-01

    Pathogenic Escherichia coli O157:H7, as well as nonpathogenic strains ATCC 11775 and ATCC 23716, grew exponentially in wounds on Golden Delicious apple fruit. The exponential growth occurred over a longer time period on fruit inoculated with a lower concentration of the bacterium than on fruit inoculated with a higher concentration. The bacterium reached the maximum population supported in the wounds regardless of the initial inoculum concentrations. Populations of E. coli O157:H7 in various concentrations of sterilized apple juice and unsterilized cider declined over time and declined more quickly in diluted juice and cider. The decline was greater in the unsterilized cider than in juice, which may have resulted from the interaction of E. coli O157:H7 with natural populations of yeasts that increased with time. Experiments on the transmission of E. coli by fruit flies, collected from a compost pile of decaying apples and peaches, were conducted with strain F-11775, a fluorescent transformant of nonpathogenic E. coli ATCC 11775. Fruit flies were easily contaminated externally and internally with E. coli F-11775 after contact with the bacterium source. The flies transmitted this bacterium to uncontaminated apple wounds, resulting in a high incidence of contaminated wounds. Populations of the bacterium in apple wounds increased significantly during the first 48 h after transmission. Further studies under commercial conditions are necessary to confirm these findings. PMID:9872751

  15. Measurement of firmness of fresh-cut sliced tomato using puncture tests : studies on sample size, probe size and direction of puncture

    NARCIS (Netherlands)

    Moreira Lana, M.; Tijskens, L.M.M.; Theije, De A.; Dekker, M.; Barrett, D.M.

    2007-01-01

    In order to investigate the firmness of tomato slices, two experiments were performed. In the first one, Monte Carlo simulation was used to study the variation in firmness within and between slices. Adding more slices and more measurements per slice reduced the SD, but in general, the efficiency of

  16. Effects of ozone on quality of fresh-cut broccoli%臭氧对鲜切青花菜品质的影响

    Institute of Scientific and Technical Information of China (English)

    陆胜民; 孔凡春; 王群

    2003-01-01

    研究了臭氧水浸泡对鲜切青花菜品质的影响.用10mg/L的臭氧水将鲜切青花菜浸泡5 min和15 min后置入0℃冷库贮藏.在贮藏期间发现臭氧抑制了青花菜的黄化,延缓了青花菜中叶绿素的降解,抑制了类胡萝卜素的合成;同时增加了失重率,降低了叶绿素荧光比值Fm/Fv,但对Vc、蛋白质和总酸并没有影响.

  17. Modeling transfer of Escherichia coli O157:H7 and Listeria monocytogenes during preparation of fresh-cut salads: impact of cutting and shredding practices.

    Science.gov (United States)

    Zilelidou, Evangelia A; Tsourou, Virginia; Poimenidou, Sofia; Loukou, Anneza; Skandamis, Panagiotis N

    2015-02-01

    Cutting and shredding of leafy vegetables increases the risk of cross contamination in household settings. The distribution of Escherichia coli O157:H7 and Listeria monocytogenes transfer rates (Tr) between cutting knives and lettuce leaves was investigated and a semi-mechanistic model describing the bacterial transfer during consecutive cuts of leafy vegetables was developed. For both pathogens the distribution of log10Trs from lettuce to knife was towards low values. Conversely log10Trs from knife to lettuce ranged from -2.1 to -0.1 for E. coli O157:H7 and -2.0 to 0 for L. monocytogenes, and indicated a more variable phenomenon. Regarding consecutive cuts, a rapid initial transfer was followed by an asymptotic tail at low populations moving to lettuce or residing on knife. E. coli O157:H7 was transferred at slower rates than L. monocytogenes. These trends were sufficiently describe