Flocculation of Pyrite Fines in Aqueous Suspensions with Corn Starch to Eliminate Mechanical Entrainment in Flotation

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Wei Ge

2015-10-01

Full Text Available The hydrophilic flocculation of pyrite fines in aqueous suspensions with corn starch was studied by measuring particle size distribution, microscopy observation and micro-flotation. Furthermore, the interaction of corn starch with pyrite was investigated by determining the adsorption density and based on zeta potential measurements and X-ray photoelectron spectrometer (XPS analysis in this work. The results of the particle size distribution measurement show that corn starch can effectively aggregate pyrite fines, and the pyrite floccules (flocs are sensitive to mechanical stirring. The micro-flotation results suggest that the mechanical entrainment of pyrite fines in flotation can be effectively eliminated through the formation of large-size flocs. The zeta potential of pyrite particles decreases with the addition of corn starch. The XPS results prove that carboxyl groups are generated on the digested corn starch, and both iron hydroxyl compounds and ferrous disulfide on the pyrite surface can chemically interact with the corn starch digested by sodium hydroxide.

Effect of electron beam irradiation on the biodegradability of aromatic aliphatic copolyester film and their blend with corn starch

Energy Technology Data Exchange (ETDEWEB)

Silva, Leonardo G. Andrade e; Poveda, Patricia N.S., E-mail: lgasilva@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Rezende, Maira L.; Rosa, Derval S. [Universidade Sao Francisco, Itatiba, SP (Brazil)

2009-07-01

Biodegradable and green plastics have been studied in the last years. The aim of this paper is to study the effect of electron beam irradiation on the biodegradability of aromatic aliphatic copolyester film and their blend with corn starch. The samples were irradiated at different doses 10 and 40 kGy in a linear accelerator. The biodegradability of the materials was evaluated by two methods: soil simulated and enzymatic. In the method enzymatic when it was used alpha-amylase, the irradiated samples presented faster biodegradation than the references non irradiated. The blend of aromatic aliphatic copolyester with corn starch (Ecobras{sup R}) irradiated presented a bigger biodegradability than the aromatic aliphatic copolyester (Ecoflex{sup R}) film in both methods studied. (author)

Enzymatic digestibility and ethanol fermentability of AFEX-treated starch-rich lignocellulosics such as corn silage and whole corn plant

Directory of Open Access Journals (Sweden)

Thelen Kurt D

2010-06-01

Full Text Available Abstract Background Corn grain is an important renewable source for bioethanol production in the USA. Corn ethanol is currently produced by steam liquefaction of starch-rich grains followed by enzymatic saccharification and fermentation. Corn stover (the non-grain parts of the plant is a potential feedstock to produce cellulosic ethanol in second-generation biorefineries. At present, corn grain is harvested by removing the grain from the living plant while leaving the stover behind on the field. Alternatively, whole corn plants can be harvested to cohydrolyze both starch and cellulose after a suitable thermochemical pretreatment to produce fermentable monomeric sugars. In this study, we used physiologically immature corn silage (CS and matured whole corn plants (WCP as feedstocks to produce ethanol using ammonia fiber expansion (AFEX pretreatment followed by enzymatic hydrolysis (at low enzyme loadings and cofermentation (for both glucose and xylose using a cellulase-amylase-based cocktail and a recombinant Saccharomyces cerevisiae 424A (LNH-ST strain, respectively. The effect on hydrolysis yields of AFEX pretreatment conditions and a starch/cellulose-degrading enzyme addition sequence for both substrates was also studied. Results AFEX-pretreated starch-rich substrates (for example, corn grain, soluble starch had a 1.5-3-fold higher enzymatic hydrolysis yield compared with the untreated substrates. Sequential addition of cellulases after hydrolysis of starch within WCP resulted in 15-20% higher hydrolysis yield compared with simultaneous addition of hydrolytic enzymes. AFEX-pretreated CS gave 70% glucan conversion after 72 h of hydrolysis for 6% glucan loading (at 8 mg total enzyme loading per gram glucan. Microbial inoculation of CS before ensilation yielded a 10-15% lower glucose hydrolysis yield for the pretreated substrate, due to loss in starch content. Ethanol fermentation of AFEX-treated (at 6% w/w glucan loading CS hydrolyzate (resulting

Enzymatic digestibility and ethanol fermentability of AFEX-treated starch-rich lignocellulosics such as corn silage and whole corn plant

Science.gov (United States)

2010-01-01

Background Corn grain is an important renewable source for bioethanol production in the USA. Corn ethanol is currently produced by steam liquefaction of starch-rich grains followed by enzymatic saccharification and fermentation. Corn stover (the non-grain parts of the plant) is a potential feedstock to produce cellulosic ethanol in second-generation biorefineries. At present, corn grain is harvested by removing the grain from the living plant while leaving the stover behind on the field. Alternatively, whole corn plants can be harvested to cohydrolyze both starch and cellulose after a suitable thermochemical pretreatment to produce fermentable monomeric sugars. In this study, we used physiologically immature corn silage (CS) and matured whole corn plants (WCP) as feedstocks to produce ethanol using ammonia fiber expansion (AFEX) pretreatment followed by enzymatic hydrolysis (at low enzyme loadings) and cofermentation (for both glucose and xylose) using a cellulase-amylase-based cocktail and a recombinant Saccharomyces cerevisiae 424A (LNH-ST) strain, respectively. The effect on hydrolysis yields of AFEX pretreatment conditions and a starch/cellulose-degrading enzyme addition sequence for both substrates was also studied. Results AFEX-pretreated starch-rich substrates (for example, corn grain, soluble starch) had a 1.5-3-fold higher enzymatic hydrolysis yield compared with the untreated substrates. Sequential addition of cellulases after hydrolysis of starch within WCP resulted in 15-20% higher hydrolysis yield compared with simultaneous addition of hydrolytic enzymes. AFEX-pretreated CS gave 70% glucan conversion after 72 h of hydrolysis for 6% glucan loading (at 8 mg total enzyme loading per gram glucan). Microbial inoculation of CS before ensilation yielded a 10-15% lower glucose hydrolysis yield for the pretreated substrate, due to loss in starch content. Ethanol fermentation of AFEX-treated (at 6% w/w glucan loading) CS hydrolyzate (resulting in 28 g/L ethanol

Starch films from a novel (Pachyrhizus ahipa) and conventional sources: Development and characterization

International Nuclear Information System (INIS)

López, Olivia V.; García, María A.

2012-01-01

Biodegradable films from ahipa, cassava and corn native starches were developed by casting method and their physicochemical, mechanical and barrier properties were analyzed taking into account the different starch botanical sources. Filmogenic suspensions were prepared; their rheological behaviors were studied and all of them exhibited film-forming ability. However, mechanical assays demonstrated that unplasticized films were too rigid, limiting their technological applications. Thus, 1.5% w/w of glycerol as plasticizer was added to filmogenic suspensions and film flexibility and extensibility were improved, this effect was more significant for ahipa and cassava starch films. Furthermore, thickness, moisture content and water solubility of the developed films were increased when plasticizer was incorporated. Glycerol addition reduced film water vapor permeability and the lowest reduction corresponded to cassava starch films due to the high viscosity of its filmogenic suspensions. Plasticized starch films resulted to be UV radiation barriers; ahipa starch films had the lowest light absorption capacity and higher transparency than cassava and corn starch films. Dynamic-mechanical analysis indicated that plasticized films were partially miscible systems exhibiting two relaxations, one attributed to the starch-rich phase and the other to the glycerol-rich one. Likewise, it could be demonstrated that glycerol exerted a major plasticizing effect on ahipa starch matrixes. Highlights: ► Ahipa, cassava and corn starch films were developed by casting method. ► Glycerol effect on film mechanical behavior was major for tuberous starch films. ► Ahipa starch films resulted to be more transparent with lower UV absorption capacity. ► Plasticized films were partially miscible systems: with a glycerol-rich and a starch-rich phase. ► Glycerol exerted a major plasticizing effect on ahipa starch films.

Powder and compaction characteristics of pregelatinized starches.

Science.gov (United States)

Rojas, J; Uribe, Y; Zuluaga, A

2012-06-01

Pregelatinized starch is widely used as a pharmaceutical aid, especially as a filler-binder. It is known that the tableting performance of excipients could be affected by their source. The aim of this study was to evaluate the powder and tableting properties of pregelatinized starches obtained from yucca, corn and rice and compare those properties with those of Starch 1500. This material had the lowest particle size, and porosity and largest density and best flow. However, yucca starch and corn starch showed an irregular granule morphology, better compactibility and compressibility than Starch 1500. Their onset of plastic deformation and their strain rate sensitivity was comparable to that of Starch 1500. These two materials showed compact disintegration slower that Starch 1500. Conversely, rice starch showed a high elasticity, and friability, low compactibility, which are undesirable for direct compression. This study demonstrated the potential use of pregelatinized starches, especially those obtained from yucca and corn as direct compression filler-binders.

Development of highly-transparent protein/starch-based bioplastics.

Science.gov (United States)

Gonzalez-Gutierrez, J; Partal, P; Garcia-Morales, M; Gallegos, C

2010-03-01

Striving to achieve cost-competitive biomass-derived materials for the plastics industry, the incorporation of starch (corn and potato) to a base formulation of albumen and glycerol was considered. To study the effects of formulation and processing, albumen/starch-based bioplastics containing 0-30 wt.% starch were prepared by thermo-plastic and thermo-mechanical processing. Transmittance measurements, DSC, DMTA and tensile tests were performed on the resulting bioplastics. Optical and tensile properties were strongly affected by starch concentration. However, DMTA at low deformation proved to be insensitive to starch addition. Thermo-mechanical processing led to transparent albumen/starch materials with values of strength at low deformation comparable to commodity plastics. Consequently, albumen biopolymers may become a biodegradable alternative to oil-derived plastics for manufacturing transparent packaging and other plastic stuffs. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

Degradation of corn starch under the influence of gamma irradiation

Energy Technology Data Exchange (ETDEWEB)

El Saadany, R M.A.; El Saadany, F M; Foda, Y H

1976-01-01

Irradiation of corn (maize) starch with different doses of gamma irradiation ranging from 1 x 10/sup 5/ rad to 1 x 10/sup 6/ rad resulted in the increase of starch acidity and reducing power. Molecular degradation was observed as a result of marked decrease in starch viscosity and intinsic viscosity as well as swelling capacity. The gelatinization time and temperature of the irradiated starch became shorter than in the control sample. Internal changes in the irradiated starch occured as a result of lowering the number of glucose unit per segment in the irradiated starch molecules. All changes were proportional to the doses of gamma irradiation used.

Degradation of corn starch under the influence of gamma irradiation

International Nuclear Information System (INIS)

El Saadany, R.M.A.; El Saadany, F.M.; Foda, Y.H.

1976-01-01

Irradiation of corn (maize) starch with different doses of gamma irradiation ranging from 1 x 10 5 rad to 1 x 10 6 rad resulted in the increase of starch acidity and reducing power. Molecular degradation was observed as a result of marked decrease in starch viscosity and intinsic viscosity as well as swelling capacity. The gelatinization time and temperature of the irradiated starch became shorter than in the control sample. Internal changes in the irradiated starch occured as a result of lowering the number of glucose unit per segment in the irradiated starch molecules. All changes were proportional to the doses of gamma irradiation used. (orig.) [de

Detoxification of corn stover and corn starch pyrolysis liquors by ligninolytic enzymes of Phanerochaete chrysosporium.

Science.gov (United States)

Khiyami, Mohammad A; Pometto, Anthony L; Brown, Robert C

2005-04-20

Phanerochaete chrysosporium (ATCC 24725) shake flask culture with 3 mM veratryl alcohol addition on day 3 was able to grow and detoxify different concentrations of diluted corn stover (Dcs) and diluted corn starch (Dst) pyrolysis liquors [10, 25, and 50% (v/v)] in defined media. GC-MS analysis of reaction products showed a decrease and change in some compounds. In addition, the total phenolic assay with Dcs samples demonstrated a decrease in the phenolic compounds. A bioassay employing Lactobacillus casei growth and lactic acid production was developed to confirm the removal of toxic compounds from 10 and 25% (v/v) Dcs and Dst by the lignolytic enzymes, but not from 50% (v/v) Dcs and Dst. The removal did not occur when sodium azide or cycloheximide was added to Ph. chrysosporium culture media, confirming the participation of lignolytic enzymes in the detoxification process. A concentrated enzyme preparation decreased the phenolic compounds in 10% (v/v) corn stover and corn starch pyrolysis liquors to the same extent as the fungal cultures.

Starch behaviors and mechanical properties of starch blend films with different plasticizers.

Science.gov (United States)

Nguyen Vu, Hoang Phuong; Lumdubwong, Namfone

2016-12-10

The main objective of the study was to gain insight into structural and mechanical starch behaviors of the plasticized starch blend films. Mechanical properties and starch behaviors of cassava (CS)/and mungbean (MB) (50/50, w/w) starch blend films containing glycerol (Gly) or sorbitol (Sor) at 33% weight content were investigated. It was found that tensile strength TS and %E of the Gly-CSMB films were similar to those of MB films; but%E of all Sor-films was identical. TS of plasticized films increased when AM content and crystallinity increased. When Sor was substituted for Gly, crystallinity of starch films and their TS increased. The CSMB and MB films had somewhat a similar molecular profile and comparable mechanical properties. Therefore, it was proposed the starch molecular profile containing amylopectin with high M¯w, low M¯w of amylose, and the small size of intermediates may impart the high TS and%E of starch films. Copyright © 2016 Elsevier Ltd. All rights reserved.

Crystallinity in starch plastics: consequences for material properties

NARCIS (Netherlands)

Soest, van J.J.G.; Vliegenthart, J.F.G.

1997-01-01

The processing of starches with biodegradable additives has made biodegradable plastics suitable for a number of applications. Starch plastics are partially crystalline as a result of residual crystallinity and the recrystallization of amylose and amylopectin. Such crystallinity is a key determinant

Technical note: a method to quantify prolamin proteins in corn that are negatively related to starch digestibility in ruminants.

Science.gov (United States)

Larson, J; Hoffman, P C

2008-12-01

Compared with floury or high-moisture corns, dry corn with a greater percentage of vitreous endosperm has been demonstrated to be negatively related to starch digestibility and milk yield of lactating dairy cows. Starch granules in corn are encapsulated by hydrophobic prolamin proteins that are innately insoluble in the rumen environment. Corn prolamin proteins are named zein, and laboratory methods to quantify zein exist but are seldom employed in ruminant nutrition because of their arduous nature. In this study, advances in cereal chemistry were combined with rapid turbidimetric methods yielding a modified turbidimetric zein method (mTZM) to quantify zein in whole corn. Ten dry corns containing unique endosperms were evaluated using the mTZM. Corns with flint, dent, floury, or opaque endosperms were found to contain 19.3, 11.3, 5.8, and 4.9 g of zein/100 g of starch, respectively. The ability of mTZM to differentiate corn endosperm types as defined by least significant difference was 2.6 g of zein/100 g of starch. Ten high-moisture corns of varying moisture content were also evaluated using the mTZM. Zein content of high-moisture corns as defined by mTZM ranged from 8.3 to 2.8 g of zein/100 g of starch with a least significant difference of 1.2 g of zein/100 g of starch. The mTZM determined that zein contents of high-moisture, floury, and opaque corns were markedly less than those of flint and dent dry corns, indicating that mTZM has the ability to quantify starch granule encapsulation by hydrophobic prolamin proteins in whole corn.

All-natural bio-plastics using starch-betaglucan composites.

Science.gov (United States)

Sagnelli, Domenico; Kirkensgaard, Jacob J K; Giosafatto, Concetta Valeria L; Ogrodowicz, Natalia; Kruczała, Krzysztof; Mikkelsen, Mette S; Maigret, Jean-Eudes; Lourdin, Denis; Mortensen, Kell; Blennow, Andreas

2017-09-15

Grain polysaccharides represent potential valuable raw materials for next-generation advanced and environmentally friendly plastics. Thermoplastic starch (TPS) is processed using conventional plastic technology, such as casting, extrusion, and molding. However, to adapt the starch to specific functionalities chemical modifications or blending with synthetic polymers, such as polycaprolactone are required (e.g. Mater-Bi). As an alternative, all-natural and compostable bio-plastics can be produced by blending starch with other polysaccharides. In this study, we used a maize starch (ST) and an oat β-glucan (BG) composite system to produce bio-plastic prototype films. To optimize performing conditions, we investigated the full range of ST:BG ratios for the casting (100:0, 75:25, 50:50, 25:75 and 0:100 BG). The plasticizer used was glycerol. Electron Paramagnetic Resonance (EPR), using TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl) as a spin probe, showed that the composite films with high BG content had a flexible chemical environment. They showed decreased brittleness and improved cohesiveness with high stress and strain values at the break. Wide-angle X-ray diffraction displayed a decrease in crystallinity at high BG content. Our data show that the blending of starch with other natural polysaccharides is a noteworthy path to improve the functionality of all-natural polysaccharide bio-plastics systems. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of pigeon pea and plantain starches on the compressional, mechanical, and disintegration properties of paracetamol tablets.

Science.gov (United States)

Dare, Kunle; Akin-Ajani, Dorothy O; Odeku, Oluwatoyin A; Itiola, Oludele A; Odusote, Omotunde M

2006-03-01

A study has been made of the effects of pigeon pea starch obtained from the plant Cajanus cajan (L) Millisp. (family Fabaceae) and plantain starch obtained from the unripe fruit of Musa paradisiaca L. (family Musaceae) on the compressional, mechanical, and disintegration properties of paracetamol tablets in comparison with official corn starch BP. Analysis of compressional properties was done by using density measurements, and the Heckel and Kawakita equations, whereas the mechanical properties of the tablets were evaluated by using tensile strength (T--a measure of bond strength) and brittle fracture index (BFI--a measure of lamination tendency). The ranking for the mean yield pressure, P(y), for the formulations containing the different starches was generally corn plasticity, was pigeon pea plastic deformation, whereas those formulations containing pigeon pea starch exhibited the highest amount of plastic deformation during tableting. The tensile strength of the tablets increased with increase in concentration of the starches while the Brittle Fracture Index decreased. The ranking for T was pigeon pea > plantain > corn starch while the ranking for BFI was corn > plantain > pigeon pea starch. The bonding capacity of the formulations was in general agreement with the tensile strength results. The disintegration time (DT) of the formulation increased with concentration of plantain and corn starches but decreased with concentration of pigeon pea starch. The general ranking of DT values was plantain disintegration of tablet is desired. The results show that the starches could be useful in various formulations depending on the intended use of the tablets with the implication that the experimental starches can be developed for commercial purposes.

Nutritional perfomance of Tupinambis merianae lizards fed with corn starch as source of energy

Directory of Open Access Journals (Sweden)

Harold Vega Parry

2009-07-01

Full Text Available Efficiency in processing complex carbohydrates as a source of energy was studied in Tupinambis merianae lizards. Four isoproteic and isoenergetic diets in which different percentages of corn starch substituted fat (0, 10, 20 and 30 dry matter in the diet were provided. Even though consumption was similar in all diets, growth and feeding conversion rates decreased significantly with corn starch supplies of 10% and more. At the end of the trial, pancreatic alpha-amylase activity showed correlated increases, yet these were insufficient to compensate corn starch supplies. Results suggest that Tupinambis merianae lizards have a restricted omnivorous capacity. Therefore, diet formulation for these lizards should exclude high molecular weight carbohydrates.

Kinetic modeling of simultaneous saccharification and fermentation of corn starch for ethanol production.

Science.gov (United States)

Białas, Wojciech; Czerniak, Adrian; Szymanowska-Powałowska, Daria

2014-01-01

Fuel ethanol production, using a simultaneous saccharification and fermentation process (SSF) of native starch from corn flour, has been performed using Saccharomyces cerevisiae and a granular starch hydrolyzing enzyme. The quantitative effects of mash concentration, enzyme dose and pH were investigated with the use of a Box-Wilson central composite design protocol. Proceeding from results obtained in optimal fermentation conditions, a kinetics model relating the utilization rates of starch and glucose as well as the production rates of ethanol and biomass was tested. Moreover, scanning electron microscopy (SEM) was applied to investigate corn starch granule surface after the SFF process. A maximum ethanol concentration of 110.36 g/l was obtained for native corn starch using a mash concentration of 25%, which resulted in ethanol yield of 85.71%. The optimal conditions for the above yield were found with an enzyme dose of 2.05 ml/kg and pH of 5.0. These results indicate that by using a central composite design, it is possible to determine optimal values of the fermentation parameters for maximum ethanol production. The investigated kinetics model can be used to describe SSF process conducted with granular starch hydrolyzing enzymes. The SEM micrographs reveal randomly distributed holes on the surface of granules.

Synchrotron X-ray Scattering Analysis of the Interaction Between Corn Starch and an Exogenous Lipid During Hydrothermal Treatment

Energy Technology Data Exchange (ETDEWEB)

E Hernandez-Hernandez; C Avila-Orta; B Hsiao; j Castro-Rosas; J Gallegos-Infante; J Morales-Castro; L Ochoa-Martinez; C Gomez-Aldapa

2011-12-31

Lipids have an important effect on starch physicochemical properties. There exist few reports about the effect of exogenous lipids on native corn starch structural properties. In this work, a study of the morphological, structural and thermal properties of native corn starch with L-alpha-lysophosphatidylcholine (LPC, the main phospholipid in corn) was performed under an excess of water. Synchrotron radiation, in the form of real-time small and wide-angle X-ray scattering (SAXS/WAXS), was used in order to track structural changes in corn starch, in the presence of LPC during a heating process from 30 to 85 C. When adding LCP, water absorption decreased within starch granule amorphous regions during gelatinization. This is explained by crystallization of the amylose-LPC inclusion complex during gelatinization, which promotes starch granule thermal stability at up to 95 C. Finally, a conceptual model is proposed for explaining the formation mechanism of the starch-LPC complex.

On spray drying of oxidized corn starch cross-linked gelatin microcapsules for drug release

International Nuclear Information System (INIS)

Dang, Xugang; Yang, Mao; Shan, Zhihua; Mansouri, Shahnaz; May, Bee K; Chen, Xiaodong; Chen, Hui; Woo, Meng Wai

2017-01-01

Spray-dried gelatin/oxidized corn starch (G/OCS) microcapsules were produced for drug release application. The prepared microcapsules were characterized through a scanning electron microscope (SEM) picture and thermogravimetric analysis (TGA). The swelling characteristics of the G/OCS microcapsules and release properties of vitamin C were then investigated. The results from structural analysis indicated that the presence of miscibility and compatibility between oxidized corn starch and gelatin, and exhibits high thermal stability up to 326 °C. The swelling of G/OCS microcapsules increased with increasing pH and reduced with decreasing ionic strength, attributed to the cross-linking between gelatin and oxidized corn starch, ionization of functional groups. Vitamin C release characteristic revealed controlled release behavior in the first 3 h of contact with an aqueous medium. This release behavior was independent of the swelling behavior indicating the potential of the encapsulating matrix to produce controlled release across a spectrum of pH environment. - Highlights: • It's first time to prepare microencapsulation with gelatin and oxidized corn starch. • The microencapsulation material can be biodegradable completely. • The production technology of microcapsule is convenient. • This work explores the potential to use oxidized starch cross-linked gelatin. • The microencapsulation material can be used for drug release.

On spray drying of oxidized corn starch cross-linked gelatin microcapsules for drug release

Energy Technology Data Exchange (ETDEWEB)

Dang, Xugang; Yang, Mao; Shan, Zhihua [National Engineering Laboratory for Clean Technology Leather Manufacture, Sichuan University, Chengdu, Sichuan 610065 (China); Mansouri, Shahnaz [Department of Chemical Engineering, Monash University, VIC 3800 (Australia); May, Bee K [School of Applied Science, RMIT University, 124 La Trobe St, Melbourne, VIC 3001 (Australia); Chen, Xiaodong [Department of Chemical Engineering, Monash University, VIC 3800 (Australia); School of Chemical and Environmental Engineering, College of Chemistry, Chemical Engineering and Material Science, Soochow University (China); Chen, Hui, E-mail: leather2088@sina.com [National Engineering Laboratory for Clean Technology Leather Manufacture, Sichuan University, Chengdu, Sichuan 610065 (China); Department of Chemical Engineering, Monash University, VIC 3800 (Australia); Woo, Meng Wai, E-mail: meng.woo@monash.edu [Department of Chemical Engineering, Monash University, VIC 3800 (Australia)

2017-05-01

Spray-dried gelatin/oxidized corn starch (G/OCS) microcapsules were produced for drug release application. The prepared microcapsules were characterized through a scanning electron microscope (SEM) picture and thermogravimetric analysis (TGA). The swelling characteristics of the G/OCS microcapsules and release properties of vitamin C were then investigated. The results from structural analysis indicated that the presence of miscibility and compatibility between oxidized corn starch and gelatin, and exhibits high thermal stability up to 326 °C. The swelling of G/OCS microcapsules increased with increasing pH and reduced with decreasing ionic strength, attributed to the cross-linking between gelatin and oxidized corn starch, ionization of functional groups. Vitamin C release characteristic revealed controlled release behavior in the first 3 h of contact with an aqueous medium. This release behavior was independent of the swelling behavior indicating the potential of the encapsulating matrix to produce controlled release across a spectrum of pH environment. - Highlights: • It's first time to prepare microencapsulation with gelatin and oxidized corn starch. • The microencapsulation material can be biodegradable completely. • The production technology of microcapsule is convenient. • This work explores the potential to use oxidized starch cross-linked gelatin. • The microencapsulation material can be used for drug release.

The pasting and gel textural properties of corn starch in glucose, fructose and maltose syrup.

Science.gov (United States)

Sun, Qingjie; Xing, Yan; Qiu, Chao; Xiong, Liu

2014-01-01

The pasting and gel textural properties of corn starch in syrup at different concentrations were investigated by Rapid Visco Analyzer (RVA) and Texture profile analysis (TPA) tests. The results showed that the pasting temperatures of corn starch greatly increased, especially at higher sugar concentration. Increasing concentration of syrup caused an increase in peak, trough and final viscosity of corn starch. Peak viscosity and the disintegration rate of starch increased in the following order: fructose syrup> maltose syrup> glucose syrup. Increasing syrup concentration to 13%, 25% and 50% resulted in a lower retrogradation rate than the control. When the maltose syrup concentration increased to 50%, the retrogradation rate decreased to 14.30% from 33.38%. The highest hardness was observed when the syrup concentration was 25%. There was a particular low hardness when the concentration of syrup was 50%. The springiness of starch gels in syrup was similar at different concentrations.

Characterization of corn starch-based edible film incorporated with nutmeg oil nanoemulsion

Science.gov (United States)

Aisyah, Y.; Irwanda, L. P.; Haryani, S.; Safriani, N.

2018-05-01

This study aimed to formulate corn starch-based edible films by varying concentrations of nutmeg oil nanoemulsion and glycerol. Furthermore, the resulted edible film was characterized by its mechanical properties and antibacterial activity. The edible films were made using corn starch, nutmeg oil nanoemulsion, and glycerol. Concentrations of nutmeg oil nanoemulsion were 1%, 2%, and 3%, and glycerol were 10%, 20%, and 30%. Results indicated that the increase of nutmeg oil nanoemulsion concentration could increase the film thickness. However, the nutmeg oil had no effect on the film tensile strength and elongation. Glycerol had no effect on the film tensile strength. The best treatment of the corn starch-based film was obtained by adding 1% of nutmeg oil and 30% of glycerol, yielding a tensile strength of 18.73 Kgf/mm2, elongation of 69.44% and thickness of 0.0840. The addition of 1% nutmeg oil nanoemulsion has been able to inhibit the growth of two types of the bacteria tested (Staphylococcus aureus and Escherichia coli).

All-natural bio-plastics using starch-betaglucan composites

DEFF Research Database (Denmark)

Sagnelli, Domenico; Kirkensgaard, Jacob Judas Kain; Giosafatto, Concetta Valeria L.

2017-01-01

functionalities chemical modifications or blending with synthetic polymers, such as polycaprolactone are required (e.g. Mater-Bi). As an alternative, all-natural and compostable bio-plastics can be produced by blending starch with other polysaccharides. In this study, we used a maize starch (ST) and an oat β...... BG content. Our data show that the blending of starch with other natural polysaccharides is a noteworthy path to improve the functionality of all-natural polysaccharide bio-plastics systems....

The pasting and gel textural properties of corn starch in glucose, fructose and maltose syrup.

Directory of Open Access Journals (Sweden)

Qingjie Sun

Full Text Available The pasting and gel textural properties of corn starch in syrup at different concentrations were investigated by Rapid Visco Analyzer (RVA and Texture profile analysis (TPA tests. The results showed that the pasting temperatures of corn starch greatly increased, especially at higher sugar concentration. Increasing concentration of syrup caused an increase in peak, trough and final viscosity of corn starch. Peak viscosity and the disintegration rate of starch increased in the following order: fructose syrup> maltose syrup> glucose syrup. Increasing syrup concentration to 13%, 25% and 50% resulted in a lower retrogradation rate than the control. When the maltose syrup concentration increased to 50%, the retrogradation rate decreased to 14.30% from 33.38%. The highest hardness was observed when the syrup concentration was 25%. There was a particular low hardness when the concentration of syrup was 50%. The springiness of starch gels in syrup was similar at different concentrations.

Effects of ruminally degradable starch levels on performance, nitrogen balance, and nutrient digestibility in dairy cows fed low corn-based starch diets

Directory of Open Access Journals (Sweden)

Guobin Luo

2017-05-01

Full Text Available Objective This trial was performed to examine the effects of ruminally degradable starch (RDS levels in total mixed ration (TMR with low corn-based starch on the milk production, whole-tract nutrient digestibility and nitrogen balance in dairy cows. Methods Eight multiparous Holstein cows (body weight [BW]: 717±63 kg; days in milk [DIM]: 169±29 were assigned to a crossover design with two dietary treatments: a diet containing 62.3% ruminally degradable starch (% of total starch, low RDS or 72.1% ruminally degradable starch (% of total starch, high RDS. Changes to the ruminally degradable levels were conducted by using either finely ground corn or steam-flaked corn as the starch component. Results The results showed that dry matter intake, milk yield and composition in dairy cows were not affected by dietary treatments. The concentration of milk urea nitrogen was lower for cows fed high RDS TMR than low RDS TMR. The whole-tract apparent digestibility of neutral detergent fiber, acid detergent fiber and crude protein decreased, and that of starch increased for cows fed high RDS TMR over those fed low RDS TMR, with no dietary effect on the whole-tract apparent digestibility of dry matter and organic matter. The proportion of urinary N excretion in N intake was lower and that of fecal N excretion in N intake was higher for cows fed high RDS TMR than those fed low RDS TMR. The N secretion in milk and the retention of N were not influenced by the dietary treatments. Total purine derivative was similar in cows fed high RDS TMR and low RDS TMR. Consequently, estimated microbial N flow to the duodenum was similar in cows fed high RDS TMR and low RDS TMR. Conclusion Results of this study show that ruminally degradable starch levels can influence whole-tract nutrient digestibility and nitrogen balance in dairy cows fed low corn-based starch diets, with no influence on performance.

Physic-chemical Study of Starch Extracted from Irradiated Corn Flour

International Nuclear Information System (INIS)

Pozo Sanchez, R. del; Alvarez Gil, M.

1986-01-01

The effects of gamma irradiation on starch extracted from irradiated samples of corn flour were studied in the range 0,6 kGy-1,0 kGy. Amylographic properties, solubility and swelling powder of starch samples were determined immediately after irradiation and at 75 days storage at environment conditions (16 0 C-31 0 C, 55%-97% H.R.). Diffraction patterns of crystalline starch were also obtained by X-rays. Gelatinization temperature, swelling powder and diffraction patterns did not change upon irradiation, but a decrease in viscosity and an increase in starch solubility were observed within the dose-range and storage time studied. (author)

In vitro digestion and physicochemical characteristics of corn starch mixed with amino acid modified by low pressure treatment.

Science.gov (United States)

Ji, Ying

2018-03-01

The digestibility and molecular structure of corn starch mixed with amino acid modified by low-pressure treatment (LPT) was investigated. Amino acid induced a significant increase in the slowly digestible starch (SDS) and decrease in the rapidly digestible starch (RDS) after LPT. The reason is the formation of ester bond between the molecular chains of amino acid and starch. Low pressure treatment altered greatly the morphology of corn starch mixed with or without amino acid. After LPT, less ordered Maltese and more granule fragments were observed for starch-amino acid complex. An increase in size distribution was obvious after LPT and the size distribution curves provided from a new variety. We found that higher enthalpy and relative crystallinity of the starch-amino acid complex were associated with a higher SDS content. It can be inferred that LPT had a greater impact on the digestion and structural characterization of corn starch mixed with amino acids. Copyright © 2017 Elsevier Ltd. All rights reserved.

Technical note: In situ ruminal starch disappearance kinetics of hull-less barley, hulled barley, and corn grains.

Science.gov (United States)

Ferreira, G; Yang, Y; Teets, C L; Brooks, W S; Griffey, C A

2018-07-01

The objective of this study was to compare ruminal starch disappearance rates of hull-less barley, hulled barley, and corn grains. Five different genotypes were used for each of the 2 barley types. In addition, each of these genotypes was grown in 2 different locations and years, resulting 10 independent barley samples for each of the 2 barley grain types. Five different genotypes of corn grain were obtained from a commercial seed company. After being ground to pass through a 4-mm screen of a cutter mill, 3.6 g of each grain was placed into a porous bag, which was then incubated in the rumen of 2 ruminally cannulated cows for 0, 4, 8, 12, 24, and 48 h. Corn grains had greater instant ruminal starch disappearances than barley grains (22.4 and 8.2%, respectively). Instant ruminal starch disappearances did not differ between hulled and hull-less barley grains. Ruminal starch fractional disappearance rates were greatest for hulled barley grains, moderate for hull-less barley grains, and lowest for corn grains (15.3, 13.9, and 7.1%/h, respectively). Ruminal starch half-life was shortest for hulled and hull-less barley grains (4.4 h) and longest for corn grains (6.6 h). Ruminal starch half-life did not differ between hulled barley and hull-less barley grains. In conclusion, using a holistic experimental design and statistical analysis, this study showed that starch from hull-less barley grains has a ruminal half-life similar to that of hulled barley grains and shorter than that of corn grains. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Application of autoclaving-cooling cycling treatment to improve resistant starch content of corn-based rice analogues

Science.gov (United States)

Hidayat, B.; Muslihudin, M.; Akmal, S.

2018-01-01

Resistant starch is one important component determining the characteristics of a functional food. The aim of the research was to determine the cooling time optimum in the autoclaving-cooling treatment to increase the resistance starch content corn-based rice analogues, with 6 level of cooling time (0 hours/control, 12 hours, 24 hours, 36 hours, 48 hours and 60 hours). The results showed that cooling at 4°C for 60 hours would increase the resistant starch content (6.27% to 15.38%), dietary fiber content (14.53% to 20.17%); and decrease the digestible starch content (61.81% to 52.70%). Cooling time level at 4°C for 24 hours, would increase the sensory score of corn-based rice analogues then back down until cooling time level of 60 hours. Microscopic analysis of granular structure using SEM indicated that cooling time had a linear correlation with cracks intensity on the granule surface of the corn-based rice analogues. The high content of resistant starch showed that the application of cooling time level at 4°C for 24 hours would improve the functional properties of corn-based rice analogues with sensory characteristics remain favorable to panelists.

Corn starch: properties and processing. January 1972-December 1987 (citations from the Food Science and Technology Abstracts data base). Report for January 1972-December 1987

International Nuclear Information System (INIS)

1987-12-01

This bibliography contains citations concerning corn starch processing. The physical and chemical properties, and nutritive value of corn starch and corn starch products are considered. Studies of gamma-irradiated corn starch are included. (This updated bibliography contains 397 citations, 123 of which are new entries to the previous edition.)

Comparison between apparent viscosity related to irradiation dose for corn starch and black pepper

International Nuclear Information System (INIS)

Casandroiu, T.; Oprita, N.; Ferdes, O.S.

1999-01-01

Dose-effect relationship was studied in the rheoviscometric behaviour of geliffied suspensions of irradiated corn starch and black pepper, as the variation of the apparent viscosity and the shear stress related to the dose. Irradiation has been performed up to 16 kGy. Black pepper was ground and sieved to three particle sizes to analyse also the influence of particle size on the apparent viscosity variation by dose. The rheoviscometric measurements have been carried out by a rotationary viscometer on geliffied suspensions of starch and black pepper, into equivalent starch concentration and alkalinised suspensions for pepper. For starch, shear stress variation by dose is exponential, where the coefficients depend on the shear rate. For black pepper, the curves of apparent viscosity relation to dose also fit an exponential equation and the influence of particle size is discussed, too. Viscometric behaviour similar to irradiation of both corn starch and black pepper could be attributed to starch degradation at relatively high doses and should be used to develop an identification and control method for the ionizing treatment of starch-based food materials. (author)

Comparative study of the physico-chemical properties of rice and corn starches grown in Indian temperate climate

Directory of Open Access Journals (Sweden)

Abida Ali

2016-01-01

Full Text Available Starches isolated from the rice (Jhelum and Kohsar and corn (PS-43 and Shalimar-maize cultivars were studied for their physico-chemical and morphological properties. Physico-chemical properties such as composition, water and oil absorption capacity, swelling power, syneresis, freeze–thaw stability and light transmittance showed significant differences among the starches. Amylose contents of starches separated from the Jhelum and Kohsar rice cultivars and PS-43 and Shalimar-maize corn cultivars were 6.33%, 4.90%, 7.52% and 8.09%, respectively. The granular size varied from 5.2 to 5.9 μm for rice starches and 11.4–12.0 μm for corn starches. Transmittance value of gelatinized pastes from all starches progressively decreased up to the 2nd day during refrigerated storage, except Kohsar rice starch which lost its clarity significantly up to 3rd day of storage. The pasting property revealed peak, breakdown and setback viscosity which were in the range of 2479–3021 cP, 962–1713 cP and 1293–2003 cP respectively.

Detoxification of corn stover and corn starch pyrolysis liquors by Pseudomonas putida and Streptomyces setonii suspended cells and plastic compost support biofilms.

Science.gov (United States)

Khiyami, Mohammad A; Pometto Iii, Anthony L; Brown, Robert C

2005-04-20

Plant biomass can be liquefied into fermentable sugars (levoglucosan then to glucose) for the production of ethanol, lactic acid, enzymes, and more by a process called pyrolysis. During the process microbial inhibitors are also generated. Pseudomonas putida (ATCC 17484) and Streptomyces setonii75Vi2 (ATCC 39116) were employed to degrade microbial inhibitors in diluted corn stover (Dcs) and diluted corn starch (Dst) pyrolysis liquors. The detoxification process evaluation included measuring total phenols and changes in UV spectra, a GC-MS analysis, and a bioassay, which employed Lactobacillus casei subsp. rhamosus (ATCC 11443) growth as an indicator of detoxification. Suspended-cell cultures illustrated limited detoxification ability of Dcs and Dst. P. putida and S. setoniiplastic compost support (PCS) biofilm continuous-stirred-tank-reactor pure cultures detoxified 10 and 25% (v/v) Dcs and Dst, whereas PCS biofilm mixed culture also partially detoxified 50% (v/v) Dcs and Dst in repeated batch culture. Therefore, PCS biofilm mixed culture is the process of choice to detoxify diluted pyrolysis liquors.

Physicochemical and Microstructural Characterization of Corn Starch Edible Films Obtained by a Combination of Extrusion Technology and Casting Technique.

Science.gov (United States)

Fitch-Vargas, Perla Rosa; Aguilar-Palazuelos, Ernesto; de Jesús Zazueta-Morales, José; Vega-García, Misael Odín; Valdez-Morales, Jesús Enrique; Martínez-Bustos, Fernando; Jacobo-Valenzuela, Noelia

2016-09-01

Starch edible films (EFs) have been widely studied due to their potential in food preservation; however, their application is limited because of their poor mechanical and barrier properties. Because of that, the aim of this work was to use the extrusion technology (Ex T) as a pretreatment of casting technique to change the starch structure in order to obtain EFs with improved physicochemical properties. To this, corn starch and a mixture of plasticizers (sorbitol and glycerol, in different ratios) were processed in a twin screw extruder to generate the starch modification and subsequently casting technique was used for EFs formation. The best conditions of the Ex T and plasticizers concentration were obtained using response surface methodology. All the response variables evaluated, were affected significatively by the Plasticizers Ratio (Sorbitol:Glycerol) (PR (S:G)) and Extrusion Temperature (ET), while the Screw Speed (SS) did not show significant effect on any of these variables. The optimization study showed that the appropriate conditions to obtain EFs with the best mechanical and barrier properties were ET = 89 °C, SS = 66 rpm and PR (S:G) = 79.7:20.3. Once the best conditions were obtained, the optimal treatment was characterized according to its microstructural properties (X-ray diffraction, Scanning Electron Microscopy and Atomic Force Microscopy) to determine the damage caused in the starch during Ex T and casting technique. In conclusion, with the combination of Ex T and casting technique were obtained EFs with greater breaking strength and deformation, as well as lower water vapor permeability than those reported in the literature. © 2016 Institute of Food Technologists®

Preliminary Investigation to Determine the Suitable Mixture Composition for Corn Starch Matrix

Science.gov (United States)

Huzaimi Zakaria, Nazri; Ngali, Zamani; Zulkefli Selamat, Mohd

2017-01-01

The use of natural fiber as reinforcement in polymeric composites has been seen a dramatically increase over the last decades. The surge in the interest of natural fiber composite or biodegradable composite is mainly due to the attractive cost of production, improved of hardness, better fatigue endurance and good thermal and mechanical resistivity. In this work, corn starch in the form of powder is utilized as the matrix of the composite. However, starch is brittle and has low strength make it inappropriate candidate for matrix binder. The main objective of this study is to modify the mechanical properties of pure corn starch by mixing it with water, glycerol and vinegar. The composition ratio of water is 60~80%, corn starch 10~35%, glycerol is 5~15% and vinegar is 0~5%, ten samples (A-J) have been manufactured and the best mixture composition is selected based on few selection criteria. The selection criteria are visual impaction, hardness and density. From the results, the samples without vinegar are not suitable to be used because of the fungus availability on the surface. Meanwhile the results from the samples with 5 ml vinegar have no fungus on their surface even has been exposed to the ambient air. While the sample C has shown the best sample based on the visual, hardness and density test.

Glycemic Response to Corn Starch Modified with Cyclodextrin Glycosyltransferase and its Relationship to Physical Properties.

Science.gov (United States)

Dura, A; Yokoyama, W; Rosell, C M

2016-09-01

Corn starch was modified with cyclodextrin glycosyltransferase (CGTase) below the gelatinization temperature. The porous granules with or without CGTase hydrolysis products may be used as an alternative to modified corn starches in foods applications. The amount and type of hydrolysis products were determined, containing mainly β-cyclodextrin (CD), which will influence pasting behavior and glycemic response in mice. Irregular surface and small holes were observed by microscopic analysis and differences in pasting properties were observed in the presence of hydrolysis products. Postprandial blood glucose in mice fed gelatinized enzymatically modified starch peaked earlier than their ungelatinized counterparts. However, in ungelatinized enzymatically modified starches, the presence of β- CD may inhibit the orientation of amylases slowing hydrolysis, which may help to maintain lower blood glucose levels. Significant correlations were found between glycemic curves and viscosity pattern of starches.

On spray drying of oxidized corn starch cross-linked gelatin microcapsules for drug release.

Science.gov (United States)

Dang, Xugang; Yang, Mao; Shan, Zhihua; Mansouri, Shahnaz; May, Bee K; Chen, Xiaodong; Chen, Hui; Woo, Meng Wai

2017-05-01

Spray-dried gelatin/oxidized corn starch (G/OCS) microcapsules were produced for drug release application. The prepared microcapsules were characterized through a scanning electron microscope (SEM) picture and thermogravimetric analysis (TGA). The swelling characteristics of the G/OCS microcapsules and release properties of vitamin C were then investigated. The results from structural analysis indicated that the presence of miscibility and compatibility between oxidized corn starch and gelatin, and exhibits high thermal stability up to 326°C. The swelling of G/OCS microcapsules increased with increasing pH and reduced with decreasing ionic strength, attributed to the cross-linking between gelatin and oxidized corn starch, ionization of functional groups. Vitamin C release characteristic revealed controlled release behavior in the first 3h of contact with an aqueous medium. This release behavior was independent of the swelling behavior indicating the potential of the encapsulating matrix to produce controlled release across a spectrum of pH environment. Copyright © 2016 Elsevier B.V. All rights reserved.

Enzymatic Modification of Corn Starch Influences Human Fecal Fermentation Profiles.

Science.gov (United States)

Dura, Angela; Rose, Devin J; Rosell, Cristina M

2017-06-14

Enzymatically modified starches have been widely used in food applications to develop new products, but information regarding digestion and fecal fermentation of these products is sparse. The objective of this study was to determine the fermentation properties of corn starch modified with α-amylase, amyloglucosidase, or cyclodextrin glycosyltransferase and the possible role of hydrolysis products. Samples differed in their digestibility and availability to be fermented by the microbiota, resulting in differences in microbial metabolites produced during in vitro fermentation. The presence or absence of hydrolysis products and gelatinization affected starch composition and subsequent metabolite production by the microbiota. Amyloglucosidase-treated starch led to the greatest production of short- and branched-chain fatty acid production by the microbiota. Results from this study could be taken into consideration to confirm the possible nutritional claims and potential health benefits of these starches as raw ingredients for food development.

Effects of plantain and corn starches on the mechanical and disintegration properties of paracetamol tablets.

Science.gov (United States)

Akin-Ajani, Olufunke D; Itiola, Oludele A; Odeku, Oluwatoyin A

2005-10-22

The effects of plantain starch obtained from the unripe fruit of the plant Musa paradisiaca L. (Musaceae) on the mechanical and disintegration properties of paracetamol tablets have been investigated in comparison with the effects of corn starch BP using a 2(3) factorial experimental design. The individual and combined effects of nature of starch binder (N), concentration of starch binder (C), and the relative density of tablet (RD) on the tensile strength (TS), brittle fracture index (BFI), and disintegration time (DT) of the tablets were investigated. The ranking of the individual effects on TS was RD > C > N, on BFI was C > RD > N and on DT was N > C > RD. The ranking for the interaction effects on TS and DT was N-C > N-RD > C-RD, while that on BFI was N-C > C-RD > N-RD. Changing nature of starch from a "low" (plantain starch) to a "high" (corn starch) level, increasing the concentration of starch binding agent from 2.5% to 10.0% wt/wt, and increasing relative density of the tablet from 0.80 to 0.90, led to increase in the values of TS and DT, but a decrease in BFI. Thus, tablets containing plantain starch had lower tensile strength and disintegration time values than those containing corn starch, but showed better ability to reduce the lamination and capping tendency in paracetamol tablet formulation. The interaction between N and C was significantly (P < .001) higher than those between N and RD and between C and RD. There is therefore the need to carefully choose the nature (N) and concentration (C) of starch used as binding agent in tablet formulations to obtain tablets of desired bond strength and disintegration properties. Furthermore, plantain starch could be useful as an alternative binding agent to cornstarch, especially where faster disintegration is required and the problems of lamination and capping are of particular concern.

The nature of hematite depression with corn starch in the reverse flotation of iron ore.

Science.gov (United States)

Shrimali, Kaustubh; Atluri, Venkata; Wang, Yan; Bacchuwar, Sanket; Wang, Xuming; Miller, Jan D

2018-08-15

The function of corn starch and the significance of the order of addition of corn starch and mono ether amine in the reverse flotation of iron ore has been investigated. Understanding hematite depression with starch and the corresponding hydrophilic state involves consideration of adsorption with amine as well as flocculation of fine hematite. Captive bubble contact angle and micro-flotation experiments indicated that amine has an affinity towards both hematite and quartz, and that the role of starch is to hinder the adsorption of amine at the hematite surface so that flotation is inhibited. Micro-flotation results confirmed that quartz does not have affinity towards starch at pH 10.5. In addition to competitive adsorption, flocculation of fine hematite occurs and images from high resolution X-ray computed tomography (HRXCT) and cryo-SEM reveal further detail regarding floc structure. These results provide substantial evidence that the fine hematite particles are flocculated in the presence of corn starch, and flocculation is dependent on the particle size of hematite, with greater flocculation for finer particles. Thus, starch is playing a dual role in the reverse flotation of iron ore, acting as a depressant by hindering amine adsorption at the hematite surface in order to maintain the hydrophilic surface state of hematite, and acting as a flocculant to aggregate fine hematite particles, which if not flocculated, could diminish the flotation separation efficiency by being transported to the froth phase during reverse flotation. Copyright © 2018 Elsevier Inc. All rights reserved.

Physical and structural changes induced by high pressure on corn starch, rice flour and waxy rice flour.

Science.gov (United States)

Cappa, Carola; Lucisano, Mara; Barbosa-Cánovas, Gustavo V; Mariotti, Manuela

2016-07-01

The impact of high pressure (HP) processing on corn starch, rice flour and waxy rice flour was investigated as a function of pressure level (400MPa; 600MPa), pressure holding time (5min; 10min), and temperature (20°C; 40°C). Samples were pre-conditioned (final moisture level: 40g/100g) before HP treatments. Both the HP treated and the untreated raw materials were evaluated for pasting properties and solvent retention capacity, and investigated by differential scanning calorimetry, X-ray diffractometry and environmental scanning electron microscopy. Different pasting behaviors and solvent retention capacities were evidenced according to the applied pressure. Corn starch presented a slower gelatinization trend when treated at 600MPa. Corn starch and rice flour treated at 600MPa showed a higher retention capacity of carbonate and lactic acid solvents, respectively. Differential scanning calorimetry and environmental scanning electron microscopy investigations highlighted that HP affected the starch structure of rice flour and corn starch. Few variations were evidenced in waxy rice flour. These results can assist in advancing the HP processing knowledge, as the possibility to successfully process raw samples in a very high sample-to-water concentration level was evidenced. This work investigates the effect of high pressure as a potential technique to modify the processing characteristics of starchy materials without using high temperature. In this case the starches were processed in the powder form - and not as a slurry as in previously reported studies - showing the flexibility of the HP treatment. The relevance for industrial application is the possibility to change the structure of flour starches, and thus modifying the processability of the mentioned products. Copyright © 2016 Elsevier Ltd. All rights reserved.

Experimental and Modeling Studies on the Synthesis and Properties of Higher Fatty Esters of Corn Starch

NARCIS (Netherlands)

Junistia, Laura; Sugih, Asaf K.; Manurung, Robert; Picchioni, Francesco; Janssen, Leon P. B. M.; Heeres, Hero J.

This paper describes a systematic study on the synthesis of higher fatty esters of corn starch (starch laurate and starch stearate) by using the corresponding vinyl esters. The reactions were carried out in DMSO using basic catalysts (Na(2)HPO(4), K(2)CO(3), and Na-acetate). The effect of the

Effect of incorporation of nutraceutical capsule waste of safflower oil in the mechanical characteristics of corn starch films

Directory of Open Access Journals (Sweden)

Camila de CAMPO

2016-01-01

Full Text Available Abstract Biodegradable films blends made of safflower oil nutraceutical capsules waste corn starch (20:4, 30:4, 40:4 and 50:4 were prepared. The objective of this study was to evaluate the influence of addition of different concentrations of safflower oil nutraceutical capsule waste in the mechanical properties (tensile strength, elongation at break, Young’s modulus and thickness of corn starch films. A decrease in tensile strength and Young’s modulus and an increase in elongation at break were observed with the increase in the content of the nutraceutical capsule waste. The results showed that the blends of safflower oil capsules waste-corn starch films demonstrated promising characteristics to form biodegradable films with different mechanical characteristics.

The influence of maltodextrins on the structure and properties of compression-molded starch plastic sheets

NARCIS (Netherlands)

Soest, van J.J.G.; Kortleve, P.M.

1999-01-01

Starch plastic sheets were prepared by compression molding of starch-based plastic granulates. The granulates were prepared by extrusion processing of mixtures of granular potato starch and several maltodextrins (5% w/w) in the presence of glycerol and water as plasticizers and lecithin as melt flow

Gelatinized and nongelatinized corn starch/ poly(epsilon-caprolactone) blends: characterization by rheological, mechanical and morphological properties

OpenAIRE

Rosa,Derval S.; Guedes,Cristina G. F.; Pedroso,Andréa G.

2004-01-01

Poly(epsilon-caprolactone)/corn starch blends containing 25, 50 and 75 wt.% starch were prepared by mechanical processing and characterized by the melt flow index (MFI), tensile test and scanning electron microscopy (SEM). For comparison, starch was used in gelatinized and nongelatinized forms and was also characterized by viscography. The addition of starch to poly(epsilon-caprolactone) reduced the MFI values, the tensile strength and the elongation at break, whereas the modulus increased. T...

Isosorbide, a green plasticizer for thermoplastic starch that does not retrogradate.

Science.gov (United States)

Battegazzore, Daniele; Bocchini, Sergio; Nicola, Gabriele; Martini, Eligio; Frache, Alberto

2015-03-30

Isosorbide is a non-toxic biodegradable diol derived from bio-based feedstock. It can be used for preparing thermoplastic starch through a semi-industrial process of extrusion. Isosorbide allows some technological advantages with respect to classical plasticizers: namely, direct mixing with starch, energy savings for the low processing temperature required and lower water uptake. Indeed, maize starch was directly mixed with the solid plasticizer and direct fed in the main hopper of a co-rotating twin screw extruder. Starch plasticization was assessed by X-ray diffraction (XRD) and dynamic-mechanical analysis (DMTA). Oxygen permeability, water uptake and mechanical properties were measured at different relative humidity (R.H.) values. These three properties turned out to be highly depending on the R.H. No retrogradation and changing of the material properties were occurred from XRD and DMTA after 9 months. Copyright © 2014 Elsevier Ltd. All rights reserved.

Influence of chitosan concentration on mechanical and barrier properties of corn starch/chitosan films.

Science.gov (United States)

Ren, Lili; Yan, Xiaoxia; Zhou, Jiang; Tong, Jin; Su, Xingguang

2017-12-01

The active packaging films based on corn starch and chitosan were prepared through mixing the starch solution and the chitosan solution (1:1) by casting. The aim of this work was to characterize and analyze the effects of the chitosan concentrations (0, 21, 41, 61 and 81wt% of starch) on physicochemical, mechanical and water vapor barrier properties as well as morphological characteristics of the corn starch/chitosan (CS/CH) films. Starch molecules and chitosan could interact through hydrogen bonding as confirmed from the shift of the main peaks to higher wavenumbers in FTIR and the reduction of crystallinity in XRD. Results showed that the incorporation of chitosan resulted in an increase in film solubility, total color differences, tensile strength and elongation at break and a decrease in Young's modulus and water vapor permeability (WVP). Elongation at break of the CS/CH films increased with increasing of chitosan concentration, and reached a maximum at 41 wt%, then declined at higher chitosan concentration. The WVP of CS/CH films increased with an increase of chitosan concentration and the same tendency observed for the moisture content. The results suggest that this biodegradable CS/CH films could potentially be used as active packaging films for food and pharmaceutical applications. Copyright © 2017 Elsevier B.V. All rights reserved.

Effects of corn-based diet starch content and corn particle size on lactation performance, digestibility, and bacterial protein flow in dairy cows.

Science.gov (United States)

Fredin, S M; Ferraretto, L F; Akins, M S; Bertics, S J; Shaver, R D

2015-01-01

An experiment was conducted to determine the effects of dietary starch content in corn-based diets and corn particle size on lactation performance, nutrient digestibility, and bacterial protein flow in dairy cows using the omasal and reticular sampling technique. Eight ruminally cannulated lactating multiparous Holstein cows were used in a replicated 4×4 Latin square design with a 2×2 factorial arrangement of treatments. Treatments were fine (FG; mean particle size=552µm) and coarse (CG; 1,270µm) ground dry shelled corn in normal- (NS) and reduced- (RS) starch diets fed as total mixed rations. The NS and RS rations contained 27 and 18% starch (dry matter basis), respectively, and were formulated by partially replacing corn with soy hull pellets. Mean dry matter intake was unaffected by treatment (23.2kg/d). Cows fed NS diets produced 1.9kg/d more milk and 0.06kg/d more milk protein compared with cows fed RS diets. Cows fed NSFG and RSCG diets produced more fat-corrected milk than did cows fed NSCG and RSFG diets. Milk urea concentration was decreased for cows fed NS diets (12.4mg/dL) compared with RS diets (13.5mg/dL). Ruminal digestibility of neutral detergent fiber (NDF; % of NDF intake) determined by the omasal sampling technique was increased in cows fed RS diets compared with NS diets (43.4 vs. 34.9%), and total-tract digestibility of NDF (% of NDF intake) was increased in cows fed RS diets compared with those fed NS diets (50.1 vs. 43.1%). Ruminal digestibility of starch (% of starch intake) determined by the omasal sampling technique was greater in cows fed NS diets compared with those fed RS diets (85.6 vs. 81.6%). Total-tract starch digestion was increased in cows fed RS diets compared with those fed NS diets (96.9 vs. 94.6%) and in cows fed FG diets compared with those fed CG diets (98.0 vs. 93.5%). Bacterial protein flow was unaffected by treatment. The omasal and reticular sampling techniques resulted in similar treatment effects for nutrient flow

Effect of starch type on the physico-chemical properties of edible films.

Science.gov (United States)

Basiak, Ewelina; Lenart, Andrzej; Debeaufort, Frédéric

2017-05-01

Food preservation is mostly related to packaging in oil-based plastics, inducing environmental problems, but this drawback could be limited by using edible/biodegradable films and coatings. Physical and chemical properties were assessed and reflect the role of the starch type (wheat, corn or potato) and thus that of the amylose/amylopectin ratio, which influences thickness, colour, moisture, wettability, thermal, surface and mechanical properties. Higher amylose content in films induces higher moisture sensitivity, and thus affects the mechanical and barrier properties. Films made from potato starch constitute a greater barrier for oxygen and water vapour though they have weaker mechanical properties than wheat and corn starch films. Starch species with higher amylose content have lower wettability properties, and better mechanical resistance, which strongly depends on the water content due to the hydrophilic nature of starch films, so they could be used for products with higher water activity, such as cheese, fruits and vegetables. It especially concerns wheat starch systems, and the contact angle indicates less hydrophilic surfaces (above 90°) than those of corn and potato starch films (below 90°). The starch origin influences optical properties and thickness: with more amylose, films are opalescent and thicker; with less, they are transparent and thinner. Copyright © 2017 Elsevier B.V. All rights reserved.

Gelatinized and nongelatinized corn starch/ poly(epsilon-caprolactone blends: characterization by rheological, mechanical and morphological properties

Directory of Open Access Journals (Sweden)

Derval S. Rosa

2004-09-01

Full Text Available Poly(epsilon-caprolactone/corn starch blends containing 25, 50 and 75 wt.% starch were prepared by mechanical processing and characterized by the melt flow index (MFI, tensile test and scanning electron microscopy (SEM. For comparison, starch was used in gelatinized and nongelatinized forms and was also characterized by viscography. The addition of starch to poly(epsilon-caprolactone reduced the MFI values, the tensile strength and the elongation at break, whereas the modulus increased. The reductions in the MFI and tensile properties were most evident when gelatinized starch was used. Viscography and SEM showed that starch was well gelatinized by the gelatinization process. Blends containing nongelatinized starch showed a good dispersion of starch but poor interfacial interactions.

Structural and mechanical characteristics of film using modified corn starch by the same two chemical processes used in different sequences.

Science.gov (United States)

Qiu, Liping; Hu, Fei; Peng, Yali

2013-01-16

Structure of dual modified starches, cross-linked esterified corn starch (CES) and esterified cross-linked corn starch (ECS), and product films (CEF and ECF) were characterized by Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction and scanning electron microscopy (SEM). The peak 1730cm(-1) of IR spectra confirmed the formation of ester carbonyl groups in starch matrix. The sequence of modification procedure had an impact on the final modification degree, resulting in structural differences of modified starches and starch films. Compared to native starch film (NF), CEF and ECF showed improved transparence (77.59% and 74.39% respectively) with compact structure, lower crystallinity (6.5% and 7.4% respectively). Results of mechanical test indicated that structure of ECF was more flexible than CEF, whereas tensile strength was higher in CEF. Accordingly, complex modification could be an effective method to adequate properties of starch films for specific processing requirements. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

In vitro digestibility of banana starch cookies.

Science.gov (United States)

Bello-Pérez, Luis A; Sáyago-Ayerdi, Sonia G; Méndez-Montealvo, Guadalupe; Tovar, Juscelino

2004-01-01

Banana starch was isolated and used for preparation of two types of cookies. Chemical composition and digestibility tests were carried out on banana starch and the food products, and these results were compared with corn starch. Ash, protein, and fat levels in banana starch were higher than in corn starch. The high ash amount in banana starch could be due to the potassium content present in this fruit. Proximal analysis was similar between products prepared with banana starch and those based on corn starch. The available starch content of the banana starch preparation was 60% (dmb). The cookies had lower available starch than the starches while banana starch had lower susceptibility to the in vitro alpha-amylolysis reaction. Banana starch and its products had higher resistant starch levels than those made with corn starch.

Using an optimal CC-PLSR-RBFNN model and NIR spectroscopy for the starch content determination in corn

Science.gov (United States)

Jiang, Hao; Lu, Jiangang

2018-05-01

Corn starch is an important material which has been traditionally used in the fields of food and chemical industry. In order to enhance the rapidness and reliability of the determination for starch content in corn, a methodology is proposed in this work, using an optimal CC-PLSR-RBFNN calibration model and near-infrared (NIR) spectroscopy. The proposed model was developed based on the optimal selection of crucial parameters and the combination of correlation coefficient method (CC), partial least squares regression (PLSR) and radial basis function neural network (RBFNN). To test the performance of the model, a standard NIR spectroscopy data set was introduced, containing spectral information and chemical reference measurements of 80 corn samples. For comparison, several other models based on the identical data set were also briefly discussed. In this process, the root mean square error of prediction (RMSEP) and coefficient of determination (Rp2) in the prediction set were used to make evaluations. As a result, the proposed model presented the best predictive performance with the smallest RMSEP (0.0497%) and the highest Rp2 (0.9968). Therefore, the proposed method combining NIR spectroscopy with the optimal CC-PLSR-RBFNN model can be helpful to determine starch content in corn.

Effects of corn-based diet starch content and neutral detergent fiber source on lactation performance, digestibility, and bacterial protein flow in dairy cows.

Science.gov (United States)

Fredin, S M; Akins, M S; Ferraretto, L F; Shaver, R D

2015-01-01

An experiment was conducted to evaluate the effects of corn-based dietary starch content and source of neutral detergent fiber (NDF) on lactation performance, nutrient digestion, bacterial protein flow, and ruminal parameters in lactating dairy cows. Eight ruminally cannulated multiparous Holstein cows averaging 193±11d in milk were randomly assigned to treatments in a replicated 4×4 Latin square design with 21-d periods. Treatment diets were high corn grain (HCG; 38% corn silage, 19% dry ground corn, and 4% soy hulls), high soy hulls (HSH; 38% corn silage, 11% dry ground corn, and 13% soy hulls), high corn silage (HCS; 50% corn silage, 6% dry ground corn, and 4% soy hulls), and low corn silage (LCS; 29% corn silage, 15% corn, and 19% soy hulls). The HCG, HSH, HCS, and LCS diets contained 29, 23, 24, and 22% starch; 27, 32, 30, and 32% total NDF; and 21, 21, 25, and 17% forage NDF (dry matter basis), respectively. Mean dry matter intake and milk yield were unaffected by treatment. Cows fed LCS had reduced milk fat content compared with HSH and HCS. The concentration of milk urea nitrogen was greater for cows fed HCS compared with the other treatments. Total-tract digestion of NDF was reduced for cows fed the HCG diet. Total-tract starch digestion was increased for cows fed the HSH and HCS compared with HCG and LCS diets. Bacterial protein flow was unaffected by treatment. Ruminal ammonia concentration was reduced in cows fed the HCG and LCS diets compared with the HCS diet. Ruminal propionate increased and the acetate:propionate ratio decreased in cows fed the LCS diet compared with the HCS diet. Ruminal pH was greater for cows fed the HCS diet compared with cows fed the LCS diet. Diet digestibility and performance of mid- to late-lactation cows fed reduced-starch diets by partially replacing corn grain with soy hulls or corn silage was similar to or improved compared with cows fed a normal-starch diet. Copyright © 2015 American Dairy Science Association

Development of starch biofilms using different carboxylic acids as plasticizers

International Nuclear Information System (INIS)

Cruz, L.C.; Miranda, C.S.; Santos, W.J. dos; Goncalves, A.P.B.; Oliveira, J.C.; Jose, N.M.

2014-01-01

Biodegradable films have become a widely exploited issue among scientists because of their positive environmental impact, besides their potential to promote better food conservation and an increase in shelf life. Starch has been studied in this field due to its availability, low cost and biodegradability. However, starch films tend to be brittle and they need addition of a plasticizer to enable their usage. In this work, starch films were synthesized with different carboxylic acids as plasticizers, aiming to observe the effect of the acids chain size in the final films properties. The acids used were: oxalic, succinic and adipic. The materials were produced by casting and characterized by DSC, TG, DRX e FTIR. It was observed that the acids chain size influenced on the thermal and structural properties of the films. (author)

Convenient synthetic method of starch/lactic acid graft copolymer ...

Indian Academy of Sciences (India)

is a potentially useful and completely biodegradable material for biodegradable plastics because of its nontoxic, low cost and its natural abundance which can be obtained from many crops including corn, wheat, rice, potato and so on (Tester and Karkallas 2002). Therefore, modification of starch, physi- cally and chemically ...

Preparation of hydroxypropyl corn and amaranth starch hydrolyzate and its evaluation as wall material in microencapsulation.

Science.gov (United States)

Kshirsagar, Amol C; Singhal, Rekha S

2008-06-01

Hydroxypropylation of starches lends it useful physicochemical and functional properties that are industrially important. The literature on hydroxypropylation using organic solvents for obtaining higher molar substitution (MS) is scantily available. The present work reports on hydroxypropylation of corn and a waxy amaranth starch to different MS with propylene oxide in an alkaline-organic medium (isopropanol). The synthesis was followed in terms of MS. The parameters optimized were starch:isopropanol ratio (w/w), reaction temperature, reaction time and the quantity of alkali required in the process. A maximal MS of 0.180 and 0.162 were obtained for hydroxypropyl corn starch (HPSC) and hydroxypropyl amaranth starch (HPSA), respectively. Enzymatic hydrolysis of the HPSC and HPSA of the above MS was carried out on a 30% (w/v) solution at a pH of 6.5 and 95°C for varying time periods using 0.1% (w/w based on starch) bacterial α-amylase, termamyl. The hydrolysis was terminated by adjusting the pH to 3.5 using 0.1N HCl. The hydrolyzates were characterized in terms of dextrose equivalent and viscosity. The hydrolyzate obtained after 3h of hydrolysis was spray dried and compared to gum arabic with respect to encapsulation of model flavourings, orange oil and lemon oil. Copyright © 2007 Elsevier Ltd. All rights reserved.

SYNTHESIS AND CHARACTERIZATION OF BIODEGRDABLE PLASTIC FROM CASAVA STARCH AND ALOE VERA EXTRACT WITH GLYCEROL PLASTICIZER

Directory of Open Access Journals (Sweden)

Mery Apriyani

2016-05-01

Full Text Available Synthesis and characterizations of Biodegradable Plastic made of Cassava Waste Starch, glycerol, acetic acid and Aloe vera extract has done. The aims of this research are to study the influence of addition of aloe vera extract in plastics mechanics properties, water vapor transmission rate and biodegradation. There are five main steps in this research, extraction of aloe vera, cassava starch preparation from cassava waste, preparations, characterization and biodegradability study of biodegradable plastic. The addition variations of aloe vera extract that used in this research are 0.01; 0.03; 0.05; 0.07 and 0.14 grams. Results showed that the addition of aloe Vera tends to increased biodegrable plastic thickness to 0.01 mm and elongation to 32.07%. However, biodegradable plastic tensile strength tends to decreased to 23.95 Mpa. Optimum tensile strength is 3.90 Mpa and elongation is 34.43%. Optimum water vapor transmission rate is 2.40 g/m2hours. Biodegradation study of biodegradable plastic showed that addition of aloe vera extract doesn’t significantly influence in plastic degradations.

Utilization of corn starch as sustrate for ß-Amylase by Bacillus SPP

African Journals Online (AJOL)

Corn starch was used as substrate for ß -amylase production from ten(10) amylolytic species of the genus Bacillus isolated locally from soil, waste water and food sources. Ten bacillus strains was made up of two strains each of Bacillus macerans, Bacillus licheniformis and Bacillus circulans. Also included are B. coagulans, ...

Effect of Nylon Bag and Protozoa on In Vitro Corn Starch Disappearance

NARCIS (Netherlands)

Zwieten, van J.T.; Vuuren, van A.M.; Dijkstra, J.

2008-01-01

An in vitro experiment was carried out to study whether the presence of protozoa in nylon bags can explain the underestimation of the in situ degradation of slowly degradable starch. Corn of a high (flint) and a low (dent) vitreousness variety was ground over a 3-mm screen, weighed in nylon bags

A physicochemical study of sugar palm (Arenga Pinnata) starch films plasticized by glycerol and sorbitol

Science.gov (United States)

Poeloengasih, Crescentiana D.; Pranoto, Yudi; Hayati, Septi Nur; Hernawan, Rosyida, Vita T.; Prasetyo, Dwi J.; Jatmiko, Tri H.; Apriyana, Wuri; Suwanto, Andri

2016-02-01

The present work explores the physicochemical characteristics of sugar palm starch film for a potential hard capsule purpose. Sugar palm (Arenga pinnata) starch films were plasticized with glycerol or sorbitol in various concentrations (30% up to 50% w/w starch). Their effects on physicochemical properties of the films were investigated. The results showed that sugar palm starch was successfully developed as the main material of film using casting method. Incorporation of both glycerol or sorbitol affected the properties of films in different ways. It was found that thickness and solubility increased as plasticizer concentration increased, whereas retraction ratio, swelling degree and swelling thickness decreased with the increased plasticizer concentration.

Utilization of sorghum, rice, corn flours with potato starch for the preparation of gluten-free pasta.

Science.gov (United States)

Ferreira, Sila Mary Rodrigues; de Mello, Ana Paula; de Caldas Rosa dos Anjos, Mônica; Krüger, Cláudia Carneiro Hecke; Azoubel, Patrícia Moreira; de Oliveira Alves, Márcia Aurelina

2016-01-15

The aim of this study was to evaluate the use of mixture of sorghum-rice-corn flour and potato starch in the development of gluten-free pasta for celiac disease patients. The experiment was designed according to simplex-lattice method and different types of gluten-free flours were used, such as sorghum, rice, corn, and potato starch. The fifteen formulations were subjected to sensory analysis (Mixed Structured Scale - MSS) and seven formulations were selected in respect to taste and grittiness. These formulations were subjected to Quantitative Descriptive Analysis (QDA), which evaluated the attributes: appearance, color, odor, hardness, elasticity, stickiness, grittiness, taste, residual bitterness and overall quality. Results showed significant difference in appearance, color and hardness. The formulations that showed the best sensory results were submitted to chemical analysis and cooking quality of pasta. It was observed that the best results for mixing is sorghum flour, rice flour and potato starch. Copyright © 2015 Elsevier Ltd. All rights reserved.

[Effect of extrusion on protein and starch bioavailability in corn and lima bean flour blends].

Science.gov (United States)

Pérez-Navarrete, Cecilia; Betancur-Ancona, David; Casotto, Meris; Carmona, Andrés; Tovar, Juscelino

2007-09-01

Extrusion is used to produce crunchy expanded foods, such as snacks. The nutritional impact of this process has not been studied sufficiently. In this study, in vitro and in vivo protein and starch bioavailability was evaluated in both raw and extruded corn (Zea mays)(C) and lima bean (Phaseolus lunatus)(B) flour blends, prepared in 75C/25B and 50C/ 50B (p/p) proportions. These were processed with a Brabender extruder at 160 degrees C, 100 rpm and 15.5% moisture content. Proximate composition showed that in the extruded products protein and ash contents increased whereas the fat level decreased. In vitro protein digestibility was higher in the extrudates (82%) than in the raw flours (77%). Potentially available starch and resistant starch contents decreased with extrusion. The in vitro assays indicated that extrusion improved protein and starch availability in the studied blends. In vivo bioavailability was evaluated using the rice weevil (Sithophilus oryzae) as a biological model. The most descriptive biomarkers of the changes suggested by the in vivo tests were body protein content (increased by extrusion) and intestinal a-amylase activity (decreased by processing). Overall, results suggest that extrusion notably increases the nutritional quality of corn and lima bean flour blends.

Physical and biological treatments of polyethylene-rice starch plastic films

Energy Technology Data Exchange (ETDEWEB)

El-Naggar, Manal M.A., E-mail: mmelnaggar@yahoo.com [Microbiology Lab., National Institute of Oceanography and Fisheries, Alexandria (Egypt); Farag, Magdy Gh. [Development Plastic Center, Victoria, Alexandria (Egypt)

2010-04-15

This study aimed to produce an industrial applicable thermo-stable {alpha}-amylase from marine Bacillus amyloliquefaciens which isolated and selected according to its significant enzyme production. The effect of different pH values and temperatures on the bacterial growth and the enzyme production was estimated using an experimental statistical design; maximum amylase production and bacterial growth was obtained at pH 7.0 and 50 deg. C. Some biodegradable polyethylene rice starch plastic films (PERS-P) were manufactured using 0, 2.5, 5, 7.5 and 10% starch concentrations. The biodegradability (reduction in the plastic elongation%) was tested using the exposure to UV radiation at {lambda}{sub 300-400nm} (intensity of about 1000 W/m{sup 2}) and the produced B. amyloliquefaciens thermo-stable {alpha}-amylase. A significant reduction in the elongation% of these biodegradable plastics was observed in both cases especially on testing the 10% PERS-P; they showed a reduction of 26% and 20%, respectively, compared to the untreated plastic films (180 {+-} 5).

Physical and biological treatments of polyethylene-rice starch plastic films

International Nuclear Information System (INIS)

El-Naggar, Manal M.A.; Farag, Magdy Gh.

2010-01-01

This study aimed to produce an industrial applicable thermo-stable α-amylase from marine Bacillus amyloliquefaciens which isolated and selected according to its significant enzyme production. The effect of different pH values and temperatures on the bacterial growth and the enzyme production was estimated using an experimental statistical design; maximum amylase production and bacterial growth was obtained at pH 7.0 and 50 deg. C. Some biodegradable polyethylene rice starch plastic films (PERS-P) were manufactured using 0, 2.5, 5, 7.5 and 10% starch concentrations. The biodegradability (reduction in the plastic elongation%) was tested using the exposure to UV radiation at λ 300-400nm (intensity of about 1000 W/m 2 ) and the produced B. amyloliquefaciens thermo-stable α-amylase. A significant reduction in the elongation% of these biodegradable plastics was observed in both cases especially on testing the 10% PERS-P; they showed a reduction of 26% and 20%, respectively, compared to the untreated plastic films (180 ± 5).

Hyperbranched polyester polyol plasticized tapioca starch/low density polyethylene blends

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Manuel Guzmán

Full Text Available Abstract In this work, low density polyethylene (LDPE/plasticized starch (TPS blends were prepared. The TPS employed in this study was obtained by plasticization of tapioca starch with a hyperbranched polyester polyol. Differential scanning calorimetry analysis showed that the melting temperature increased with the TPS content. The opposite effect was exhibited in the crystallization temperature and additional changes were not observed during the heating. X-ray diffraction analysis showed a reduction in intensity of the peak at Bragg’s angle 17.5°, proving a diminution on A type crystallinity with the increasing amount of LDPE. Micrographs obtained by scanning electron microscopy exhibited starch granules without destructure. TPS acted as a filler to LDPE, since the mechanical properties (Young’s modulus and tensile strength improved ostensibly. The Young’ modulus and tensile strength decreased with the amount of LDPE, however, the elongation at break exhibited an opposite behavior.

Physicochemical properties of sugar palm starch film: Effect of concentration and plasticizer type

Science.gov (United States)

Prasetyo, D. J.; Apriyana, W.; Jatmiko, T. H.; Hernawan; Hayati, S. N.; Rosyida, V. T.; Pranoto, Y.; Poeloengasih, C. D.

2017-07-01

In order to find the best formula for capsule shell production, this present work dealt with exploring physicochemical properties of sugar palm (Arenga pinnata) starch film as a function of different kinds and various concentrations of plasticizers. The films were prepared by casting method at different formula: starch 9-11%, glycerol or sorbitol 35-45% and polyethylene-glycol 400 (PEG 400) 5-9%. Appearance, thickness, retraction ratio, moisture content, swelling behavior and solubility of the film in water were analyzed. Both glycerol and sorbitol are compatible with starch matrix. On the contrary, PEG 400 did not form a film with suitable characteristics. The result reveals that glycerol- and sorbitol-plasticized films appeared translucent, homogenous, smooth and slightly brown in all formulas. Different type and concentration of plasticizers altered the physicochemical of film in different ways. The sorbitol-plasticized film had lower moisture content (≤ 10%) than that of glycerol-plasticized film (≥ 18%). In contrast, film plasticized with sorbitol showed higher solubility in water (28-35%) than glycerol-plasticized film (22-28%). As the concentration of both plasticizers increased, there was an increasing tendency on thickness and solubility in water. Conversely, retraction ratio and swelling degree decreased when both plasticizers concentration increased. In conclusion, the sorbitol-plasticized film showed a potency to be developed as hard capsule material.

Effect of thermostable α-amylase injection on mechanical and physiochemical properties for saccharification of extruded corn starch.

Science.gov (United States)

Myat, Lin; Ryu, Gi-Hyung

2014-01-30

In industry, a jet cooker is used to gelatinize starch by mixing the starch slurry with steam under pressure at 100-175 °C. A higher degree of starch hydrolysis in an extruder is possible with glucoamylase. Unfortunately, it is difficult to carry out liquefaction and saccharification in parallel, because the temperature of gelatinization will be too high and will inactivate glucoamylase. Since the temperature for liquefaction and saccharification is different, it is hard to change the temperature from high (required for liquefaction) to low (required for saccharification). The industrial gelatinization process is usually carried out with 30-35% (w/w) dry solids starch slurry. Conventional jet cookers cannot be used any more at high substrate concentrations owing to higher viscosity. In this study, therefore, corn starch was extruded at different melt temperatures to overcome these limitations and to produce the highest enzyme-accessible starch extrudates. Significant effects on physical properties (water solubility index, water absorption index and color) and chemical properties (reducing sugar and % increase in reducing sugar after saccharification) were achieved by addition of thermostable α-amylase at melt temperatures of 115 and 135 °C. However, there was no significant effect on % increase in reducing sugar of extruded corn starch at 95 °C. The results show the great potential of extrusion with thermostable α-amylase injection at 115 and 135 °C as an effective pretreatment for breaking down starch granules, because of the significant increase (P < 0.05) in % reducing sugar and enzyme-accessible extrudates for saccharification yield. © 2013 Society of Chemical Industry.

Incorporation of Sunflower Oil and d-alpha-tocopherol Effect on Mechanical Properties and Permeability of Corn Starch Composite Edible Film

Directory of Open Access Journals (Sweden)

Pramono Putro Utomo

2015-06-01

Full Text Available Corn starch-based films are inherently brittle and lack the necessary mechanical integrity for conventional packaging. However, the incorporation of additives can potentially improve the mechanical properties and processability of starch films. In this work sunflower oil (SO and vitamin E (d-alpha-tocopherol at three levels each (0.05%, 0.1% and 0.15% (w/vtotal and (0.18%, 0.36% and 0.54% (w/vtotal were incorporated into corn starch films using a solution casting method to improve the mechanical and water vapour transmission rate (WVTR properties. The addition of SO and vitamin E increased elongation at break of starch-based film while decreased tensile strength and WVTR of starch-based film. The best edible film obtained on addition of sunflower oil concentration of 0.15% and 0.54%, vitamin E with a value of 0.121 mm thickness, tensile strength of 65.38 kg/cm2, elongation at break 14.17% and WVTR 1144 g/m2 24 hours.

Effects of ionic conduction on hydrothermal hydrolysis of corn starch and crystalline cellulose induced by microwave irradiation.

Science.gov (United States)

Tsubaki, Shuntaro; Oono, Kiriyo; Onda, Ayumu; Yanagisawa, Kazumichi; Mitani, Tomohiko; Azuma, Jun-Ichi

2016-02-10

This study investigated the effects of ionic conduction of electrolytes under microwave field to facilitate hydrothermal hydrolysis of corn starch and crystalline cellulose (Avicel), typical model biomass substrates. Addition of 0.1M NaCl was effective to improve reducing sugar yield by 1.61-fold at unit energy (kJ) level. Although Avicel cellulose was highly recalcitrant to hydrothermal hydrolysis, addition of 0.1M MgCl2 improved reducing sugar yield by 6.94-fold at unit energy (kJ). Dielectric measurement of the mixture of corn starch/water/electrolyte revealed that ionic conduction of electrolytes were strongly involved in facilitating hydrothermal hydrolysis of polysaccharides. Copyright © 2015 Elsevier Ltd. All rights reserved.

Morphological analysis of thermoplastic starch films and montmorillonite (TPS/MMT) using vegetable oils of Brazilian Cerrado as plasticizers

International Nuclear Information System (INIS)

Schlemmer, Daniela; Sales, Maria Jose A.; Angelica, Romulo S.; Gomes, Ana Cristina M.M.

2009-01-01

Biopolymers can be used where petrochemical plastics have applications with short life. The excellent degradation of starch and its low cost make it an alternative for obtaining biodegradable plastics. To obtain thermoplastic starch (TPS) is necessary mechanical shake, high temperature and plasticizers. In this work, TPS were produced using three different vegetable oils from Brazilian's cerrado as plasticizers: buriti, macauba or pequi. Materials are also produced with montmorillonite (MMT). All the materials were analyzed by scanning electronic microscopy (SEM) and X-ray diffraction (XRD). The starch micrographs revealed irregular delaminate with a predominance of starch and 'holes' for the oils. In nanocomposites the clusters of clay are dispersed without a defined standard. It was understood that the plasticizers and processing completely changed the structure of starch causing a decrease in their crystallinity degree. Almost all nanocomposites presented exfoliate structure, only one presented intercalated structure. (author)

Mechanical and barrier properties of starch-based films plasticized with two- or three component deep eutectic solvents.

Science.gov (United States)

Zdanowicz, Magdalena; Johansson, Caisa

2016-10-20

The aim of this work was to prepare two- and three-components deep eutectic solvents (DES) and investigate their potential as starch plasticizers. Starch/DES films were prepared via casting method. Mechanical properties, water vapor- and oxygen transmission rates were measured; additionally contact angle and moisture sorption were determined and FTIR analysis was applied on the films. Native potato starch and hydroxypropylated and oxidized starch (HOPS) with common plasticizers (e.g. polyols, urea) and DES were studied. Moreover, influence of three methods of DES introduction and concentration of plasticizer on the films properties were compared. HOPS films were prepared by two methods: as non-cured and cured samples. Some of DESs containing citrate anion exhibited crosslinking ability of polysaccharide matrix. Non-cured HOPS/DES films exhibited more favourable mechanical and barrier properties than cured analogue films. Samples prepared with unmodified potato starch had higher mechanical and barrier properties than films made with HOPS. Starch-based films plasticized with novel DESs with parallel crosslinking activity exhibited satisfactory mechanical and barrier properties. Copyright © 2016 Elsevier Ltd. All rights reserved.

Acetylation of banana (Musa paradisiaca L.) and corn (Zea mays L.) starches using a microwave heating procedure and iodine as catalyst: II. Rheological and structural studies.

Science.gov (United States)

Sánchez-Rivera, Mirna M; Almanza-Benitez, Sirlen; Bello-Perez, Luis A; Mendez-Montealvo, Guadalupe; Núñez-Santiago, María C; Rodriguez-Ambriz, Sandra L; Gutierrez-Meráz, Felipe

2013-02-15

The effect of iodine concentration on the acetylation of starches with low and moderate degree of substitution (DS<0.5) and its impact on the physicochemical feature and structural features was evaluated. The acetylated starches were prepared with 0.03 mol anhydroglucose unit, 0.12 mol of anhydride acetic, and 0.6, 0.9 or 1.4 mM of molecular iodine as catalyst in a sealed Teflon vessel using microwave heating (600 W/2 min). Pasting profile and rheological properties were obtained under steady flow; dynamic oscillatory test was used. Structural features were obtained by HPSEC-RI. In acetylated starches, DS and acetyl groups increased when the iodine concentration increased, corn starch showed higher values than banana starch. The viscosity of acetylated starches decreased relative to unmodified starches while, acetylated corn starch had lower value than acetylated banana starch. In the flow curves, a non-Newtonian pattern (shear-thinning) was shown in the pastes of native and modified starches. Storage modulus (G') and loss modulus (G") showed low dependence on frequency (G'αω(0.1); G"αω(0.2)) on frequency sweep test, which is characteristic of a viscoelastic gel. Debranched native banana and corn starches presented trimodal chain-length distribution. The pattern was maintained in the acetylated starches, but with different level of short and long chains. The structural differences in native and acetylated samples explain the rheological characteristics in both starches. Copyright © 2012 Elsevier Ltd. All rights reserved.

Enzymatically hydrolysed, acetylated and dually modified corn starch: physico-chemical, rheological and nutritional properties and effects on cake quality.

Science.gov (United States)

Sahnoun, Mouna; Ismail, Nouha; Kammoun, Radhouane

2016-01-01

Corn starch was treated by enzymatic hydrolysis with Aspergillus oryzae S2 α-amylase, acetylation with vinyl acetate, and dual modification. The dual modified starch displayed a higher substitution degree than the acetylated starch and lower reducing sugar content than the hydrolysed starch. The results revealed that the cooling viscosity and amylose content of those products decrease (P cake formulations at 5 and 10 % concentrations on a wheat flour basis and compared to native starch. The results revealed that when applied at 5 % concentrations, the modified starches reduced the hardness, cohesion, adhesion and chewiness of baked cakes and enhanced their elasticity, volume, height, crust color, and appearance as compared to native starch. These effects were more pronounced for the cake incorporating the dually modified starch.

Physical and structural properties and thermal behaviour of starch-poly(ɛ-caprolactone) blend films for food packaging

OpenAIRE

Ortega Toro, Rodrigo; Contreras, Jessica; Talens Oliag, Pau; Chiralt A.

2015-01-01

Structural and physical properties (barrier, mechanical, and optical properties) and thermal behaviour of corn starch-PCL blend films, containing glycerol as plasticizer, obtained by compression moulding, at 160 °C and 130 bars, were studied. The stability on the films properties was also evaluated. Blend films showed phase separation of the polymers in a heterogeneous matrix with starch rich regions and PCL rich regions. Nevertheless, a small miscibility of PCL in the starch phase was detec...

Starch degradability of dry and ensiled high-moisture grains of corn hybrids with different textures at different grinding degrees

Directory of Open Access Journals (Sweden)

Wagner dos Reis

2011-02-01

Full Text Available This research evaluated corn grains with flint and dent texture (ensiled high-moisture or dried, submitted to grinding degrees, using the in situ ruminal degradation technique. Three rumen canulated adult sheeps were used in a complete randomized design, using a factorial outline 2 x 2 x 3, with two corn hybrids (flint and dent texture, two conservation methods (ensiled high-moisture and dry and three grinding degress (whole, coarsely and finely ground, corresponding to the sieve of 12; 10 and 8 mm. Starch soluble fraction (A of the dent hybrid ensiled corn grains was greater comparing to the dry materials and in both conservation forms this fraction was reduced in the flint texture hybrid, while the insoluble fraction potentially degradable (B the opposite occurred. The degradation potential was higher in grains ensiled in two textures. The ensiled allowed more starch effective degradation in relation to dry grain in two textures and the grains dent texture hybrid also increased such degradation in both conservation methods. The dent texture and the ensiled high-moisture grains proved the best option considering the starch degradability. Regardless of the conservation forms, the grains of corn hybrid flint texture should be finely ground, for providing higher ruminal degradation, while for the dent texture hybrid, the coarsely and whole grinding are the most suitable for ensiled and dry grain, respectively.

Physical, mechanical and barrier properties of corn starch films incorporated with plant essential oils.

Science.gov (United States)

Ghasemlou, Mehran; Aliheidari, Nahal; Fahmi, Ronak; Shojaee-Aliabadi, Saeedeh; Keshavarz, Behnam; Cran, Marlene J; Khaksar, Ramin

2013-10-15

Corn starch-based films are inherently brittle and lack the necessary mechanical integrity for conventional packaging. However, the incorporation of additives can potentially improve the mechanical properties and processability of starch films. In this work two essential oils, Zataria multiflora Boiss (ZEO) or Mentha pulegium (MEO) at three levels (1%, 2% and 3% (v/v)), were incorporated into starch films using a solution casting method to improve the mechanical and water vapor permeability (WVP) properties and to impart antimicrobial activity. Increasing the content of ZEO or MEO from 2% to 3% (v/v) increased values for elongation at break from 94.38% to 162.45% and from 53.34% to 107.71% respectively, but did not significantly change tensile strength values of the films. The WVP properties of the films decreased from 7.79 to 3.37 or 3.19 g mm m(-2) d(-1) kPa(-1) after 3% (v/v) ZEO or MEO incorporation respectively. The oxygen barrier properties were unaffected at the 1% and 2% (v/v) oil concentration used but oxygen transmission increased with 3% (v/v) for both formulations. The films' color became slightly yellow as the levels of ZEO or MEO were increased although transparency was maintained. Both films demonstrated antimicrobial activity with films containing ZEO more effective against Escherichia coli and Staphylococcus aureus than those containing MEO. These results suggest that ZEO and MEO have the potential to be directly incorporated into corn starch to prepare antimicrobial biodegradable films for various food packaging applications. Copyright © 2013 Elsevier Ltd. All rights reserved.

Preparation and characterization of biodegradable composites based on brazilian cassava starch, corn starch and green coconut fibers

Energy Technology Data Exchange (ETDEWEB)

Ramirez, Maria Guadalupe Lomeli; Muniz, Graciela I. Bolzon de.; Satyanarayana, Kestur G.; Tanobe, Valcineide; Iwakiri, Setsuo, E-mail: glomeli12@hotmail.com [Universidade Federal do Parana (UFPR), Curitiba, Parana (Brazil). Centro de Ciencias Florestais e da Madeira

2010-07-01

Increasing search for new materials with high premium on eco-friendliness, new trend is emerging in materials development such as composites, which are well established for a wide variety of applications. With growing interest and importance of renewable bioresources has led to more stress on the use of locally available materials. This paper presents preliminary results on the preparation and characterization of composites based on Brazilian coconut fibers and starches of cassava and corn. The raw materials were characterized for their morphology, chemical composition, and thermal properties and X-ray diffraction studies. Coir fibers were also tested for their tensile properties showing increasing strength and Young's modulus with decreasing diameter, while the % elongation remaining constant. Lignin content of coir was found to be 35%. Structure and properties of composites containing 0, 5 10, 15% fibers in both the matrices and prepared by compression molding would be compared. For the 2 types of starch, there was an increase in the tensile strength by the increasing proportion of fiber. The effect of moisture in the composite stress affects the strength and percentage elongation. The water absorption was higher in the composites made from cassava starch. (author)

Preparation and characterization of biodegradable composites based on brazilian cassava starch, corn starch and green coconut fibers

International Nuclear Information System (INIS)

Ramirez, Maria Guadalupe Lomeli; Muniz, Graciela I. Bolzon de.; Satyanarayana, Kestur G.; Tanobe, Valcineide; Iwakiri, Setsuo

2010-01-01

Increasing search for new materials with high premium on eco-friendliness, new trend is emerging in materials development such as composites, which are well established for a wide variety of applications. With growing interest and importance of renewable bioresources has led to more stress on the use of locally available materials. This paper presents preliminary results on the preparation and characterization of composites based on Brazilian coconut fibers and starches of cassava and corn. The raw materials were characterized for their morphology, chemical composition, and thermal properties and X-ray diffraction studies. Coir fibers were also tested for their tensile properties showing increasing strength and Young's modulus with decreasing diameter, while the % elongation remaining constant. Lignin content of coir was found to be 35%. Structure and properties of composites containing 0, 5 10, 15% fibers in both the matrices and prepared by compression molding would be compared. For the 2 types of starch, there was an increase in the tensile strength by the increasing proportion of fiber. The effect of moisture in the composite stress affects the strength and percentage elongation. The water absorption was higher in the composites made from cassava starch. (author)

Total antioxidant capacity and starch digestibility of muffins baked with rice, wheat, oat, corn and barley flour.

Science.gov (United States)

Soong, Yean Yean; Tan, Seow Peng; Leong, Lai Peng; Henry, Jeya Kumar

2014-12-01

Muffins are a popular snack consumed in western and emerging countries. Increased glycemic load has been implicated in the aetiology of diabetes. This study examined the starch digestibility of muffins baked with rice, wheat, corn, oat and barley flour. Rapidly digested starch (RDS) was greatest in rice (445 mg/g) and wheat (444 mg/g) muffins, followed by oat (416 mg/g), corn (402 mg/g) and barley (387 mg/g). Total phenolic content was found to be positively correlated with total antioxidative capacity and inversely related to the RDS of muffins. The phenolic content was highest in muffin baked with barley flour (1,687 μg/g), followed by corn (1,454 μg/g), oat (945 μg/g), wheat (705 μg/g), and rice (675 μg/g) flour. Browning was shown not to correlate with free radical scavenging capacity and digestibility of muffins. The presence of high phenolic content and low RDS makes barley muffin an ideal snack to modulate glycemic response. Copyright © 2014 Elsevier Ltd. All rights reserved.

Physical stability and moisture sorption of aqueous chitosan-amylose starch films plasticized with polyols

DEFF Research Database (Denmark)

Cervera, Mirna Fernández; Karjalainen, Milja; Airaksinen, Sari

2004-01-01

The short-term stability and the water sorption of films prepared from binary mixtures of chitosan and native amylose maize starch (Hylon VII) were evaluated using free films. The aqueous polymer solutions of the free films contained 2% (w/w) film formers, glycerol, or erythritol as a plasticizer...... in the crystallinity of the films are evident within a 3-month period of storage, and the changes in the solid state are dependent on the plasticizer and storage conditions. When stored at ambient conditions for 3 months, the aqueous chitosan-amylose starch films plasticized with erythritol exhibited a partly...

Possibilities of utilization of co-products from corn grain ethanol and starch production

Directory of Open Access Journals (Sweden)

Semenčenko Valentina V.

2013-01-01

Full Text Available In recent decades, the expansion of alternative fuels production from crops traditionally used for food and animal feed has led to significant changes in the field of energy production, agriculture and food industry. Starch and sugar feedstocks for ethanol production (corn, wheat, sugar beet, sugar cane, etc. require increasing arable land to meet market demands for the biofuel production. Although intensive studies are being carried out in order to identify improved and more cost-effective methods for the utilization of lignocellulosic and communal waste in the production of alcohol fuel, the possibility of using dry distillers’ grains with solubles (DDGS, by-product of bioethanol production from corn and wheat as well as alcoholic beverages industry, is now in focus. Application of DDGS in livestock and poultry diets in concentrations greater than traditional could positively affect the economic viability of this biofuel production, but also stabilize the current imbalance in the food and animal feed market. However, DDGS feedstuff should not be treated as a perfect substitute for corn because the complexity of ration formulation determined at the farm or feedlot level is driven by energy and protein and other nutrient requirements, as well as their relative costs in the ration. Nevertheless, processing of corn by wet milling provides a multitude of co-products suitable for feedstuffs, food industry, pharmaceuticals, chemistry etc. Some of the most important wet milling co-products that have their use in feedstuffs are corn gluten feed and corn gluten meal. The use of DDGS as a substitute for traditional feed could prevent indirect land-use changes associated with biofuel production, and therefore preserve the environmental destruction by saving the forests and permanent pastures. The use of distiller’s grains can be beneficial to biofuel growth as this is an additional, the second largest, source of income accounting of 10-20% total

Ileal Endogenous Amino Acid Flow Response to Nitrogen-free Diets with Differing Ratios of Corn Starch to Dextrose in Pigs

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C. Kong

2014-08-01

Full Text Available The objective of this study was to determine the responses in the digestibility of dry matter (DM and amino acid (AA composition of ileal endogenous flow (IEF of pigs (initial body weight, 69.1±6.46 kg fed N-free diets (NFD formulated with different ratios of corn starch to dextrose. Fifteen pigs fitted with a T-cannula at the distal ileum were fed 5 diets according to a triplicated 5×2 incomplete Latin-square design. Each period consisted of a 5-d adjustment period and 2 d of ileal digesta collection for 12 h on each of d 6 and 7 and between each period, there was a 5-d recovery period to avoid abnormal weight loss. The ratios of corn starch to dextrose investigated were 0:879, 293:586, 586:293, 779:100, and 879:0 for diet numbers 1, 2, 3, 4 and 5, respectively, and chromic oxide (5 g/kg was used as an indigestible index. Ileal DM digestibility was greater in Diet 1 than that in Diet 4 (89.5% vs 87.3%, p<0.01 but they were not different from Diet 2, 3, or 5. The IEF for most of indispensable AA were not different among diets with the exception of Met, in which a lack of corn starch or dextrose gave lower (p = 0.028 IEF of Met than diets containing corn starch and dextrose. Likewise, the dispensable AA and total AA in the IEF did not differ among diets. The respective IEF of AA (mg/kg of dry matter intake in pigs fed Diets 1, 2, 3, 4, or 5 were 301, 434, 377, 477,or 365 for Lys, 61, 89, 71, 87, or 61 for Met, and 477, 590, 472, 520, or 436 for Thr. Proline was the most abundant AA in the IEF followed by Gly, Glu, and Asp and together accounted for approximately 50% of the total ileal AA flows of pigs fed NFD. In conclusion, the variation in proportion of corn starch and dextrose in a NFD does not largely affect estimates of IEF of N and AA for growing-finishing pigs.

Metabolic Engineering of Lactobacillus plantarum for Direct l-Lactic Acid Production From Raw Corn Starch.

Science.gov (United States)

Okano, Kenji; Uematsu, Gentaro; Hama, Shinji; Tanaka, Tsutomu; Noda, Hideo; Kondo, Akihiko; Honda, Kohsuke

2018-05-01

Fermentative production of optically pure lactic acid (LA) has attracted great interest because of the increased demand for plant-based plastics. For cost-effective LA production, an engineered Lactobacillus plantarum NCIMB 8826 strain, which enables the production of optically pure l-LA from raw starch, is constructed. The wild-type strain produces a racemic mixture of d- and l-LA from pyruvate by the action of the respective lactate dehydrogenases (LDHs). Therefore, the gene encoding D-LDH (ldhD) is deleted. Although no decrease in d-LA formation is observed in the ΔldhD mutant, additional disruption of the operon encoding lactate racemase (larA-E), which catalyzes the interconversion between d- and l-LA, completely abolished d-LA production. From 100 g L -1 glucose, the ΔldhD ΔlarA-E mutant produces 87.0 g L -1 of l-LA with an optical purity of 99.4%. Subsequently, a plasmid is introduced into the ΔldhD ΔlarA-E mutant for the secretion of α-amylase from Streptococcus bovis 148. The resulting strain could produce 50.3 g L -1 of l-LA from raw corn starch with a yield of 0.91 (g per g of consumed sugar) and an optical purity of 98.6%. The engineered L. plantarum strain would be useful in the production of l-LA from starchy materials. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Acetylation and characterization of banana (Musa paradisiaca) starch.

Science.gov (United States)

Bello-Pérez, L A; Contreras-Ramos, S M; Jìmenez-Aparicio, A; Paredes-López, O

2000-01-01

Banana native starch was acetylated and some of its functional properties were evaluated and compared to corn starch. In general, acetylated banana starch presented higher values in ash, protein and fat than corn acetylated starch. The modified starches had minor tendency to retrogradation assessed as % transmittance of starch pastes. At high temperature acetylated starches presented a water retention capacity similar to their native counterpart. The acetylation considerably increased the solubility of starches, and a similar behavior was found for swelling power. When freeze-thaw stability was studied, acetyl banana starch drained approximately 60% of water in the first and second cycles, but in the third and fourth cycles the percentage of separated water was low. However, acetyl corn starch showed lower freeze-thaw stability than the untreated sample. The modification increased the viscosity of banana starch pastes.

Strength of cellulosic fiber/starch acetate composites with variable fiber and plasticizer content

DEFF Research Database (Denmark)

Joffe, Roberts; Madsen, Bo; Nättinen, Kalle

2015-01-01

In this experimental study, the performance of injection-molded short flax and hemp fibers in plasticized starch acetate were analyzed in terms of strength. Parameters involved in the analysis are a variable fiber and plasticizer content. The measured strength of the composites varies in the range...... of 12–51 MPa for flax fibers and 11–42 MPa for hemp fibers, which is significantly higher than the properties of the unreinforced starch acetate matrix. The micro-structural parameters used in modeling of composite strength were obtained from optical observations and indirect measurements. Some...

Influence of starch origin on rheological properties of concentrated aqueous solutions

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Stojanović Željko P.

2011-01-01

Full Text Available The rheological properties of corn and potato starch concentrated aqueous solutions were investigated at 25ºC. The starches were previously dispersed in water and the solutions were obtained by heating of dispersions at 115-120ºC for 20 minutes. The solutions of potato starch were transparent, while the corn starch solutions were opalescent. The results of dynamic mechanical measurements showed that the values of viscosity, h, storage modulus, G′, and loss modulus, G″, of the corn starch solutions increased with the storage time. This phenomenon was not observed for the potato starch solutions. It was assumed that the increase of h, G′ and G″ is the result of starch solutions retrogradation. The potato starch solutions retrogradation did not occur probably because of the phosphates presence. The viscosity of 2 mass % corn starch solution is less than the viscosity of 2 mass % potato starch solution. By increasing the concentration of corn starch solution the gel with elastic behavior was formed. The corn starch solutions formed gel as early as at 4 mass % concentration, while potato starch solutions achieved the gel state at the concentration of 5 mass %. The value of exponent m (G′ and G″ µ wm during the transition of potato starch solutions to gel is 0.414, which gives the fractal dimensions for corn starch of 2.10. The obtained value of fractal dimension corresponds to slow aggregation. The corn starch solutions with the starch concentrations higher than 4 mass % form weak gels. For these solutions the values of modulus in rubber plateau were determined. It was found that the modulus in rubber plateau increased with the concentration by the exponent of 4.36. Such high exponent value was obtained in the case when the tridimensional network is formed, i.e. when supermolecular structures like associates or crystal domains are formed.

Metabolic engineering of Aspergillus oryzae for efficient production of l-malate directly from corn starch.

Science.gov (United States)

Liu, Jingjing; Li, Jianghua; Shin, Hyun-Dong; Du, Guocheng; Chen, Jian; Liu, Long

2017-11-20

l-Malate, an important chemical building block, has been widely applied in the food, pharmaceutical, and bio-based materials industries. In previous work, we engineered Aspergillus oryzae by rewiring the reductive tricarboxylic acid pathway to produce l-malate from glucose. To decrease the production cost, here, we further engineered A. oryzae to efficiently produce l-malate directly from corn starch with simultaneous liquefaction-saccharification and fermentation. First, a promoter PN5 was constructed by quintuple tandem of the 97-bp fragment containing the cis-element of the glucoamylase gene promoter (PglaA), and with the promoter PN5, the transcriptional level of glaA gene increased by 25-45%. Then, by co-overexpression of glaA, a-amylase (amyB) and a-glucosidase (agdA) genes with the promoter PN5, the l-malate titer increased from 55.5g/L to 72.0g/L with 100g/L corn starch in shake flask. In addition, to reduce the concentration of byproducts succinate and fumarate, a fumarase from Saccharomyces cerevisiae, which facilitated the transformation of fumarate to l-malate, was overexpressed. As a result, the concentration of succinate and fumarate decreased from 12.6 and 1.29g/L to 7.8 and 0.59g/L, and the l-malate titer increased from 72.0g/L to 78.5g/L. Finally, we found that the addition of glucose at the initial fermentation stage facilitated the cell growth and l-malate synthesis, and the l-malate titer further increased to 82.3g/L by co-fermentation of 30g/L glucose and 70g/L corn starch, with a productivity of 1.18g/L/h and a yield of 0.82g/g total carbon sources. Copyright © 2017 Elsevier B.V. All rights reserved.

Determining Machining Parameters of Corn Byproduct Filled Plastics

Science.gov (United States)

In a collaborative project between the USDA and Northern Illinois University, the use of corn ethanol processing byproducts (i.e., DDGS) as bio-filler materials in the compression molding of phenolic plastics has been studied. This paper reports on the results of a machinability study in the milling...

Characterization of starch-based bioplastics from jackfruit seed plasticized with glycerol.

Science.gov (United States)

Santana, Renata Ferreira; Bonomo, Renata Cristina Ferreira; Gandolfi, Olga Reinert Ramos; Rodrigues, Luciano Brito; Santos, Leandro Soares; Dos Santos Pires, Ana Clarissa; de Oliveira, Cristiane Patrícia; da Costa Ilhéu Fontan, Rafael; Veloso, Cristiane Martins

2018-01-01

Biodegradable films based on starches from different botanical sources exhibited physicochemical and functional properties which were related with the starch characteristics. However, had inadequate mechanical properties and were hard and brittle. In this research, jackfruit seed starch plasticized with glycerol were developed and characterized. The starch and glycerol concentrations ranged from 2 to 6% w/w and 20 to 60 g/100 g starch, respectively. Bioplastics were obtained by the casting method and characterized in terms of color, mechanical properties, solubility, water vapor permeability ( WVP ), morphology and free energy of the hydrophobic interaction. Electronic micrographics showed the presence of some intact starch granules. The bioplastics were hydrophilic and those of 6% starch and 40% glycerol were the most hydrophilic ([Formula: see text] = 41.35 mJ m -1 ). The solubility of the films presented a direct relationship with the starch concentration ranging from 16.42 to 23.26%. Increased opacity and color difference were observed with increasing starch concentration. The WVP ranged from 1.374 × 10 -3 to 3.07 × 10 -4  g m/day m 2 which was positively related with the concentration of starch and glycerol. Tensile strength, percent elongation and Young's Modulus indicated that the jackfruit starch and glycerol provided a film with good mechanical properties. The results replaced that jackfruit starch can be used to develop films, with low opacity, moderate WVP and relatively high mechanical stability, by using glycerol in the gelatinized starch dispersions.

Plasticizer effect on the properties of biodegradable blend film from rice starch-chitosan

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Thawien Bourtoom

2008-04-01

Full Text Available The properties of biodegradable blend film from rice starch-chitosan with different plasticizers were determined. Three plasticizers comprising sorbitol (SOR, glycerol (GLY and polyethylene glycol (PEG were studied over a range of concentration from 20 to 60%. Increasing concentration of these plasticizers resulted in decreased tensile strength (TS concomitant with an increase in elongation at break (E, water vapor permeability (WVP and film solubility (FS. SOR plasticized films were the most brittle, with the highest tensile strength (TS, 26.06 MPa. However, its effect on WVP was low (5.45 g.mm/m2.day.kPa. In contrast, GLY and PEG plasticized films had a flexible structure contradictory to a low TS (14.31MPa and 16.14MPa, respectively providing a high WVP (14.52 g.mm/m2.day.kPa and 14.69 g.mm/m2.day.kPa, respectively. SOR plasticized films, demonstrated little higher FS compared to PEG and GLY plasticized films but not significant different (p<0.05. The color of biodegradable blend film from rice starch-chitosan was more affected by the concentration of the plasticizer used than by its type. Nine moisture sorption models were applied to experimental data. Moisture content of the film increased at elevated water activity. The time to reach equilibrium moisture content (EMC was about 20-24 days at lower humidity and 13-16 days at higher humidities. The EMC of glycerol and sorbitol rice starchchitosan biodegradable blend films showed a logarithmic increase at above 0.59 aw and reached the highest moisture content of 51.46% and 42.97 % at 0.95 aw, whereas PEG rice starch-chitosan biodegradable blend films did not show much increase in moisture content.

Development of corn starch based green composites reinforced with Saccharum spontaneum L fiber and graft copolymers--evaluation of thermal, physico-chemical and mechanical properties.

Science.gov (United States)

Kaith, B S; Jindal, R; Jana, A K; Maiti, M

2010-09-01

In this paper, corn starch based green composites reinforced with graft copolymers of Saccharum spontaneum L. (Ss) fiber and methyl methacrylates (MMA) and its mixture with acrylamide (AAm), acrylonitrile (AN), acrylic acid (AA) were prepared. Resorcinol-formaldehyde (Rf) was used as the cross-linking agent in corn starch matrix and different physico-chemical, thermal and mechanical properties were evaluated. The matrix and composites were found to be thermally more stable than the natural corn starch backbone. Further the matrix and composites were subjected for biodegradation studies through soil composting method. Different stages of biodegradation were evaluated through FT-IR and scanning electron microscopic (SEM) techniques. S. spontaneum L fiber-reinforced composites were found to exhibit better tensile strength. On the other hand Ss-g-poly (MMA) reinforced composites showed maximum compressive strength and wear resistance than other graft copolymers reinforced composite and the basic matrix. (c) 2010 Elsevier Ltd. All rights reserved.

Relationships between dry matter content, ensiling, ammonia-nitrogen, and ruminal in vitro starch digestibility in high-moisture corn samples.

Science.gov (United States)

Ferraretto, L F; Taysom, K; Taysom, D M; Shaver, R D; Hoffman, P C

2014-05-01

The objectives of the study were (1) to determine relationships between high-moisture corn (HMC) dry matter (DM), ammonia-N [% of crude protein (CP)], and soluble CP concentrations, and pH, with 7-h ruminal in vitro starch digestibility (ivStarchD), and (2) to evaluate the effect of ensiling on pH, ammonia-N, soluble CP, and ivStarchD measurements in HMC. A data set comprising 6,131 HMC samples (55 to 80% DM) obtained from a commercial feed analysis laboratory was used for this study. Month of sample submittal was assumed to be associated with length of the ensiling period. Data for month of sample submittal were analyzed using Proc Mixed in SAS (SAS Institute Inc., Cary, NC) with month as a fixed effect. Regressions to determine linear and quadratic relationships between ivStarchD and ammonia-N, soluble CP, pH, and DM content were performed using Proc Mixed. The ivStarchD increased by 9 percentage units from October to August of the following year. Similar results were observed for ammonia-N and soluble CP with increases from 1.8 to 4.6% of CP and 31.3 to 46.4% of CP, respectively, from October to August of the following year. Ammonia-N was positively related to ivStarchD (R(2)=0.61). The DM content of HMC at silo removal was negatively related (R(2)=0.47) to ivStarchD with a decrease of 1.6 percentage units in ivStarchD per 1-percentage-unit increase in DM content. The pH of HMC was negatively related to ammonia-N (R(2)=0.53), soluble CP (R(2)=0.57), and ivStarchD (R(2)=0.51). Combined, ammonia-N, DM, soluble CP, and pH provided a good prediction of ivStarchD (adjusted R(2)=0.70). Increasing pH, ammonia-N, soluble CP, and ivStarchD values indicate that HMC may need up to 10 mo of ensiling to reach maximum starch digestibility. Ammonia-N, DM content, soluble CP concentration, and pH are good indicators of ruminal in vitro starch digestibility for high-moisture corn. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights

Application of wheat B-starch in biodegradable plastic materials

Czech Academy of Sciences Publication Activity Database

Šárka, E.; Kruliš, Zdeněk; Kotek, Jiří; Růžek, L.; Korbářová, A.; Bubník, Z.; Růžková, M.

2011-01-01

Roč. 29, č. 3 (2011), s. 232-242 ISSN 1212-1800 R&D Projects: GA ČR GA525/09/0607 Institutional research plan: CEZ:AV0Z40500505 Keywords : biodegradable plastic * polycaprolactone * B-starch Subject RIV: JI - Composite Materials Impact factor: 0.522, year: 2011 http://www.agriculturejournals.cz/publicFiles/39918.pdf

Sorption and vapor transmission properties of uncompressed and compressed microcellular starch foam.

Science.gov (United States)

Glenn, Gregory M; Klamczynski, Artur P; Takeoka, Gary; Orts, William J; Wood, Delilah; Widmaier, Robert

2002-11-20

Microcellular starch foams (MCFs) are made by a solvent-exchange process and consist of a porous matrix with pores generally ranging from approximately 2 microm to submicrometer size. MCF may potentially be useful as a slow-release agent for volatile compounds because of its ability to sorb chemicals from the atmosphere and to absorb liquids into its porous structure, and because it can be compressed to form a starch plastic. MCF made of high-amylose corn and wheat starches was prepared with or without 2% (w/w) silicone oil (SO) or palmitic acid (PA). The MCF was loaded with 1% of various volatile compounds with vapor pressures ranging from 0.02 to 28 mm. The MCF depressed the vapor pressure from 0.37 to 37% compared to a control containing no MCF. Incorporating SO or PA in the matrix of the MCF had little effect on sorption of volatiles. Compressing MCF at 1.4, 6.9, and 69 MPa made a starch plastic with varying porosity. The vapor transmission rate of various volatile compounds through MCF was positively correlated to the vapor pressure of the test compound but was inversely proportional to the compression force used to form the starch plastic. The results indicate that uncompressed and compressed MCFs could be effective slow-release agents for a variety of volatile compounds, especially if used together.

Edible Film from Polyblend of Ginger Starch, Chitosan, and Sorbitol as Plasticizer

Science.gov (United States)

Sariningsih, N.; Putra, Y. P.; Pamungkas, W. P.; Kusumaningsih, T.

2018-03-01

Polyblend ginger starch/chitosan based edible film has been succesfully prepared and characterized. The purpose of this research was to produce edible film from polyblend of ginger starch, chitosan, and sorbitol as plasticizer. The resulted edible film were characterized by using FTIR, TGA and UTM. Edible film of ginger starch had OH vibration (3430 cm-1). Besides, edible film had elongation up to 15.63%. The thermal degradation of this material reached 208°C indicating high termal stability. The water uptake of the edible film was 42.85%. It concluded that edible film produce in this research has potential as a packaging.

Physical and mechanical properties of LDPE incorporated with different starch sources

Science.gov (United States)

Kormin, Shaharuddin; Kormin, Faridah; Dalour Hossen Beg, Mohammad; Bijarimi Mat Piah, Mohd

2017-08-01

In this study it was investigated the incorporation of different starches, such as sago starch, corn starch, potato starch, tapioca starch and wheat starch, in low-density polyethylene matrix (LDPE) to enhanced mechanical properties and to obtain partially biodegradable product with the aim to reduce the plastics wastes in the environment. For comparison, virgin LDPE, LDPE with different sources of starch blends were prepared and characterized under the same conditions. The starches were mixed to the LDPE using a twin screw extruder to guarantee the homogeneity of the formulations. The compound were shaping processed by injection moulding. The characterization of those compounds was done by physical (density, MFI), mechanical (Universal tensile machine). The addition of starch to LDPE reduced the MFI values, the tensile strength, elongation at break and impact strength, whereas the elastic modulus, flexural modulus and flexural strength increased. LDPE/SS show the good mechanical behavior compared to other formulation. The physical and mechanical properties were evident when 5 and 30 wt% were added. Water uptake increased with increased starch content and immersion time. The time taken for the composites to equilibrate was about one month even when they were immersed completely in water.

Effects of acid hydrolysis intensity on the properties of starch/xanthan mixtures.

Science.gov (United States)

Jiang, Min; Hong, Yan; Gu, Zhengbiao; Cheng, Li; Li, Zhaofeng; Li, Caiming

2018-01-01

The effects of acid hydrolysis intensity on the physicochemical properties of starch/xanthan gum (XG) system were studied. Waxy corn starch (WCS) was subjected to different concentrations of hydrochloric acid, and crystallization and relative molecular weight analysis were performed. The results revealed that the starch granules became smaller during acid hydrolysis. X-ray diffraction pattern analysis showed that the crystal structure did not change with acid hydrolysis. Evaluation of the properties and digestibility of different acid-thinned starch/XG systems indicated that the viscosity of acid-thinned starch/XG decreased with increased acid hydrolysis intensity. Rheological property measurements indicated that the compound systems were a pseudo-plastic fluid, which is a typical weak gel structure. Finally, we show that the WCS1.0M/XG has the highest stability of the tested mixtures. We conclude that adjusting the conditions of acid hydrolysis improves the stability and food quality-enhancing properties of starch. Copyright © 2017 Elsevier B.V. All rights reserved.

Design and evaluation of corn starch-bonded Rhizophora spp. particleboard phantoms for SPECT/CT imaging

Science.gov (United States)

Hamid, Puteri Nor Khatijah Abd; Yusof, Mohd Fahmi Mohd; Aziz Tajuddin, Abd; Hashim, Rokiah; Zainon, Rafidah

2018-01-01

The aim of this study was to design and evaluate of corn starch-bonded Rhizophora spp. particleboards as phantom for SPECT/CT imaging. The phantom was designed according to the Jaszczak phantom commonly used in SPECT imaging with dimension of 22 cm diameter and 18 cm length. Six inserts with different diameter were made for insertion of vials filled with 1.6 µCi/ml of 99mTc unsealed source. The particleboard phantom was scanned using SPECT/CT imaging protocol. The contrast of each vial for particleboards phantom were calculated based on the ratio of counts in radionuclide volume and phantom background and compared to Perspex® and water phantom. The results showed that contrast values for each vial in particleboard phantomis near to 1.0 and in good agreement with Perspex® and water phantoms as common phantom materials for SPECT/CT. The paired sample t-test result showed no significant difference of contrast values between images in particleboard phantoms and that in water. The overall results showed the potential of corn starch-bonded Rhizophora spp. as phantom for quality control and dosimetry works in SPECT/CT imaging.

Effects of electron beam irradiation on properties of corn starch undergone periodate oxidation mechanism blended with polyvinyl alcohol

Science.gov (United States)

Bee, Soo-Tueen; Sin, Lee Tin; Ratnam, C. T.; Yap, Bee-Fen; Rahmat, A. R.

2018-02-01

This work was performed to examine the properties of pristine PVOH and PVOH-starch blends under exposure of different irradiation dosages. The periodate oxidation method was used to produce dialdehyde starch. The application of low dosages of electron beam irradiation (≤10 kGy) has improved the tensile strength by forming crosslinking networks. However, the tensile strength drastically declined when radiated at 30 kGy due to the reduction of available hydroxyl groups inside polymer matrix for intermolecular interaction. Also, the incorporation of corn starch and dialdehyde starch has significantly reduced the melting temperature and enthalpy of melting of PVOH blends due to cessation of the hydrogen bonding between PVOH and starch molecules. The crystallite size for deflection planes (1 0 1), (1 0 1) and (2 0 0) for all PVOH blends was significant reduced when irradiated. The electron beam irradiation has also weakened the hydrophilic characteristic of all PVOH blends as evidenced in infrared and microscopy analysis.

Starch hydrolysis modeling: application to fuel ethanol production.

Science.gov (United States)

Murthy, Ganti S; Johnston, David B; Rausch, Kent D; Tumbleson, M E; Singh, Vijay

2011-09-01

Efficiency of the starch hydrolysis in the dry grind corn process is a determining factor for overall conversion of starch to ethanol. A model, based on a molecular approach, was developed to simulate structure and hydrolysis of starch. Starch structure was modeled based on a cluster model of amylopectin. Enzymatic hydrolysis of amylose and amylopectin was modeled using a Monte Carlo simulation method. The model included the effects of process variables such as temperature, pH, enzyme activity and enzyme dose. Pure starches from wet milled waxy and high-amylose corn hybrids and ground yellow dent corn were hydrolyzed to validate the model. Standard deviations in the model predictions for glucose concentration and DE values after saccharification were less than ± 0.15% (w/v) and ± 0.35%, respectively. Correlation coefficients for model predictions and experimental values were 0.60 and 0.91 for liquefaction and 0.84 and 0.71 for saccharification of amylose and amylopectin, respectively. Model predictions for glucose (R2 = 0.69-0.79) and DP4+ (R2 = 0.8-0.68) were more accurate than the maltotriose and maltose for hydrolysis of high-amylose and waxy corn starch. For yellow dent corn, simulation predictions for glucose were accurate (R2 > 0.73) indicating that the model can be used to predict the glucose concentrations during starch hydrolysis.

Protein and starch digestibilities and mineral availability of products developed from potato, soy and corn flour.

Science.gov (United States)

Gahlawat, P; Sehgal, S

1998-01-01

A technique for development of potato flour was standardized. Five products viz. cake, biscuit, weaning food, panjiri and ladoo were prepared incorporating potato flour, defatted soy flour and corn flour. Baking and roasting were the major processing techniques employed for the development of these products. Protein, ash and fat contents of potato flour were almost similar to those of raw potatoes. Significant differences in protein, ash and fat contents of all the products were observed. Protein and starch digestibility of potato flour was significantly higher than that of raw potatoes. Protein digestibility increased by 12 to 17 percent on baking or roasting of products. Processed products had significantly higher starch digestibility and mineral availability compared to raw products. Thus, it can be concluded that roasting and baking are effective means of improving starch and protein digestibility and mineral availability of products.

Determination of Machining Parameters of Corn Byproduct Filled Plastics

Science.gov (United States)

In a collaborative project between the USDA and Northern Illinois University, the use of ethanol corn processing by-products as bio-filler materials in the compression molding of phenolic plastics has been studied. This paper reports on the results of a machinability study in the milling of various ...

Influence of thickness on properties of plasticized oat starch films

Directory of Open Access Journals (Sweden)

Melicia Cintia Galdeano

2013-08-01

Full Text Available The aim of this study was to investigate the effect of thickness (between 80 and 120 µm on apparent opacity, water vapor permeability and mechanical properties (tensile and puncture of oat starch films plasticized with glycerol, sorbitol, glycerol:sorbitol mixture, urea and sucrose. Films were stored under 11, 57, 76 and 90% relative humidity (RH to study the mechanical properties. It was observed that the higher the thickness, the higher was the opacity values. Films without the plasticizer were more opaque in comparison with the plasticized ones. Glycerol:sorbitol films presented increased elongation with increasing thickness at all RH. Puncture force showed a strong dependence on the film thickness, except for the films plasticized with sucrose. In general, thickness did not affect the water permeability.

Effect of corn silage hybrids differing in starch and neutral detergent fiber digestibility on lactation performance and total-tract nutrient digestibility by dairy cows.

Science.gov (United States)

Ferraretto, L F; Fonseca, A C; Sniffen, C J; Formigoni, A; Shaver, R D

2015-01-01

Selection for hybrids with greater starch and NDF digestibility may be beneficial for dairy producers. The objective of this study was to determine the effect of feeding a TMR containing a floury-leafy corn silage hybrid (LFY) compared with a brown midrib corn silage hybrid (BMR) for intake, lactation performance, and total-tract nutrient digestibility in dairy cows. Ninety-six multiparous Holstein cows, 105±31d in milk at trial initiation, were stratified by DIM and randomly assigned to 12 pens of 8 cows each. Pens were randomly assigned to 1 of 2 treatments, BMR or LFY, in a completely randomized design; a 2-wk covariate period with cows fed a common diet followed by a 14-wk treatment period with cows fed their assigned treatment diet. Starch digestibilities, in situ, in vitro, and in vivo, were greater for LFY compared with BMR; the opposite was observed for NDF digestibility. Cows fed BMR consumed 1.7kg/d more dry matter than LFY. Although, actual-, energy-, and solids-corrected milk yields were greater for BMR than LFY, feed conversions (kg of milk or component-corrected milk per kg of DMI) did not differ. Fat-corrected milk and milk fat yield were similar, as milk fat content was greater for cows fed LFY (4.05%) than BMR (3.83%). Cows fed BMR had lower milk urea nitrogen concentration, but greater milk protein and lactose yields compared with LFY. Body weight change and condition score were unaffected by treatment. Total-tract starch digestibility was greater for cows fed the LFY corn silage; however, dry matter intake and milk and protein yields were greater for cows fed the BMR corn silage. Although total-tract starch digestibility was greater for cows fed the LFY corn silage, feed efficiency was not affected by hybrid type due to greater dry matter intake and milk and protein yields by cows fed the BMR corn silage. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Hyperbranched polyester polyol plasticized tapioca starch/low density polyethylene blends

Energy Technology Data Exchange (ETDEWEB)

Guzman, Manuel; Giraldo, Diego; Murillo, Edwin, E-mail: edwinalbertomurillo@gmail.com [Universidad de Antioquia, Medellin (Colombia); Universidad Francisco de Paula Santander, San Jose de Cucuta (Colombia)

2017-01-15

n this work, low density polyethylene (LDPE)/plasticised starch (TPS) blends were prepared. The TPS employed in this study was obtained by plasticization of tapioca starch with a hyperbranched polyester polyol. Differential scanning calorimetry analysis showed that the melting temperature increased with the TPS content. The opposite effect was exhibited in the crystallization temperature and additional changes were not observed during the heating. X-ray diffraction analysis showed a reduction in intensity of the peak at Bragg’s angle 17.5°, proving a diminution on A type crystallinity with the increasing amount of LDPE. Micrographs obtained by scanning electron microscopy exhibited starch granules without destructure. TPS acted as a filler to LDPE, since the mechanical properties (Young's modulus and tensile strength) improved ostensibly. The Young' modulus and tensile strength decreased with the amount of LDPE, however, the elongation at break exhibited an opposite behavior. (author)

Hyperbranched polyester polyol plasticized tapioca starch/low density polyethylene blends

International Nuclear Information System (INIS)

Guzman, Manuel; Giraldo, Diego; Murillo, Edwin

2017-01-01

n this work, low density polyethylene (LDPE)/plasticised starch (TPS) blends were prepared. The TPS employed in this study was obtained by plasticization of tapioca starch with a hyperbranched polyester polyol. Differential scanning calorimetry analysis showed that the melting temperature increased with the TPS content. The opposite effect was exhibited in the crystallization temperature and additional changes were not observed during the heating. X-ray diffraction analysis showed a reduction in intensity of the peak at Bragg’s angle 17.5°, proving a diminution on A type crystallinity with the increasing amount of LDPE. Micrographs obtained by scanning electron microscopy exhibited starch granules without destructure. TPS acted as a filler to LDPE, since the mechanical properties (Young's modulus and tensile strength) improved ostensibly. The Young' modulus and tensile strength decreased with the amount of LDPE, however, the elongation at break exhibited an opposite behavior. (author)

Conductivity and electrical properties of corn starch-chitosan blend biopolymer electrolyte incorporated with ammonium iodide

Science.gov (United States)

Yusof, Y. M.; Shukur, M. F.; Illias, H. A.; Kadir, M. F. Z.

2014-03-01

This work focuses on the characteristics of polymer blend electrolytes based on corn starch and chitosan doped with ammonium iodide (NH4I). The electrolytes were prepared using the solution cast method. A polymer blend comprising 80 wt% starch and 20 wt% chitosan was found to be the most amorphous blend and suitable to serve as the polymer host. Fourier transform infrared spectroscopy analysis proved the interaction between starch, chitosan and NH4I. The highest room temperature conductivity of (3.04 ± 0.32) × 10-4 S cm-1 was obtained when the polymer host was doped with 40 wt% NH4I. This result was further proven by field emission scanning electron microscopy study. All electrolytes were found to obey the Arrhenius rule. Dielectric studies confirm that the electrolytes obeyed non-Debye behavior. The temperature dependence of the power law exponent s for the highest conducting sample follows the quantum mechanical tunneling model.

Effect of starch source (corn, oats or wheat) and concentration on fermentation by equine fecal microbiota in vitro

Science.gov (United States)

Aims: The goal was to determine the effect of starch source (corn, oats and wheat) and concentration on: 1) total amylolytic bacteria, Group D Gram-positive cocci (GPC), lactobacilli, and lactate-utilizing bacteria, and 2) fermentation by equine microflora. Methods and Results: When fecal washed cel...

Effect of Plasticizer Type and Concentration on Tensile, Thermal and Barrier Properties of Biodegradable Films Based on Sugar Palm (Arenga pinnata Starch

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Muhammed L. Sanyang

2015-06-01

Full Text Available The use of starch based films as a potential alternative choice to petroleum derived plastics is imperative for environmental waste management. This study presents a new biopolymer (sugar palm starch for the preparation of biodegradable packaging films using a solution casting technique. The effect of different plasticizer types (glycerol (G, sorbitol (S and glycerol-sorbitol (GS combination with varying concentrations (0, 15, 30 and 45, w/w% on the tensile, thermal and barrier properties of sugar palm starch (SPS films was evaluated. Regardless of plasticizer types, the tensile strength of plasticized SPS films decreased, whereas their elongation at break (E% increased as the plasticizer concentrations were raised. However, the E% for G and GS-plasticized films significantly decreased at a higher plasticizer concentration (45% w/w due to the anti-plasticization effect of plasticizers. Change in plasticizer concentration showed an insignificant effect on the thermal properties of S-plasticized films. The glass transition temperature of SPS films slightly decreased as the plasticizer concentration increased from 15% to 45%. The plasticized films exhibited increased water vapor permeability values from 4.855 × 10−10 to 8.70 × 10−10 g·m−1·s−1·Pa−1, irrespective of plasticizer types. Overall, the current study manifested that plasticized sugar palm starch can be regarded as a promising biopolymer for biodegradable films.

Hydrolysis of native and heat-treated starches at sub-gelatinization temperature using granular starch hydrolyzing enzyme.

Science.gov (United States)

Uthumporn, U; Shariffa, Y N; Karim, A A

2012-03-01

The effect of heat treatment below the gelatinization temperature on the susceptibility of corn, mung bean, sago, and potato starches towards granular starch hydrolysis (35°C) was investigated. Starches were hydrolyzed in granular state and after heat treatment (50°C for 30 min) by using granular starch hydrolyzing enzyme for 24 h. Hydrolyzed heat-treated starches showed a significant increase in the percentage of dextrose equivalent compared to native starches, respectively, with corn 53% to 56%, mung bean 36% to 47%, sago 15% to 26%, and potato 12% to 15%. Scanning electron microscopy micrographs showed the presence of more porous granules and surface erosion in heat-treated starch compared to native starch. X-ray analysis showed no changes but with sharper peaks for all the starches, suggested that hydrolysis occurred on the amorphous region. The amylose content and swelling power of heat-treated starches was markedly altered after hydrolysis. Evidently, this enzyme was able to hydrolyze granular starches and heat treatment before hydrolysis significantly increased the degree of hydrolysis.

A study of a novel coprocessed dry binder composed of α-lactose monohydrate, microcrystalline cellulose and corn starch.

Science.gov (United States)

Mužíková, Jitka; Srbová, Alena; Svačinová, Petra

2017-12-01

This paper deals with a study of the novel coprocessed dry binder Combilac®, which contains 70% of α-lactose monohydrate, 20% of microcrystalline cellulose and 10% of native corn starch. These tests include flow properties, compressibility, lubricant sensitivity, tensile strength and disintegration time of tablets. Compressibility is evaluated by means of the energy profile of compression process, test of stress relaxation and tablet strength. The above-mentioned parameters are also evaluated in the physical mixture of α-lactose monohydrate, microcrystalline cellulose and native corn starch and compared with Combilac. Combilac shows much better flowability than the physical mixture of the used dry binders. Its compressibility is better, tablets possess a higher tensile strength. Neither Combilac, nor the physical mixture can be compressed without lubricants due to high friction and sticking to the matrix. Combilac has a higher lubricant sensitivity than the physical mixture of the dry binders. Disintegration time of Combilac tablets is comparable with the disintegration time of tablets made from the physical mixture.

Flour mixture of rice flour, corn and cassava starch in the production of gluten-free white bread

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Ana Cristina Ballesteros López

2004-03-01

Full Text Available The use of rice flour corn and cassava starch was evaluated in several formulations aiming to find a flour mixture to replace wheat flour in the production of free-gluten white bread. Production parameters were evaluated through sensory analysis. The resulting breads were evaluated taking into account physical parameters (crumb appearance, specific volume and moisture and sensorial parameters (flavor, appearance, crumb texture, crust color and satisfaction. Regarding flavor and moisture, breads prepared with the three different ingredients were not statistically different at 5% probability by the Tuckey test. However, they differed significantly regarding the specific volume, crumb texture, crust color, degree of satisfaction and external appearance. Rice flour bread presented the best parameters, being preferred by the sensory evaluation panel, followed by corn starch bread and cassava starch bread. Breads prepared with rice flour resulted in a softer product, presenting a better consistency with small alveoli homogeneously distributed. As far as crumb texture was concerned, corn starch bread presented larger alveoli, while cassava starch resulted in bread with expandable and gummy crumb, with granulation without alveoli, and undesirable sensorial characteristics. Production parameters were established based on these results and a mixture of flours, composed by 45% rice flour, 35% corn starch and 20% cassava starch presented good results originating bread with crumb formed by uniform and well distributed cells, and pleasant flavor and appearance.Para desenvolver um sucedâneo para o pão de forma, isento de glúten, foram testadas as influências dos amidos de milho, de mandioca e da farinha de arroz, bem como das etapas de mistura, fermentação e assamento na qualidade do mesmo. Os parâmetros de fabricação foram determinados por meio de análises sensoriais durante a produção. As características sensoriais dos pães foram comparadas por

Comparison of the Performance of Corn Starch Coagulant Aid Accompany with Alum, Polyaluminum Chloride and Ferric Chloride Coagulants in Turbidity Removal from Water

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Leila Mosleh

2014-09-01

Full Text Available Background: The most important process in water treatment plant is coagulation and flocculation. Regular chemical coagulant which used in Iran are aluminum sulfate (Alum and ferric chloride. Chemical coagulants have hazardous effect on human health and their cost is high for developing country. The purpose of this study was to evaluate the comparison of chemical coagulants accompany with corn starch as a coagulant aid, for the turbidity removal from water. Methods: This study was accomplished in pilot-scale with synthetic turbid water using clay. In this research, initial turbidity of 250 and 500 NTU was experimented. Chemical coagulant dose during the experiment was 1, 2 and 5 ppm and natural coagulant dose was 0, 0.1, 0.3, 0.5 and 0.7 ppm. Results: The results showed that maximum removal efficiency of turbidity in initial turbidity of 250 NTU belonged to poly aluminum chloride with 5 ppm dosage and corn starch with 0.7 ppm dosage which removed and reduced the initial turbidity to 98.48% and 3.73 NTU, respectively. Moreover, in initial turbidity of 500 NTU the maximum removal efficiency was 98.52% which belonged to ferric chloride and corn starch (5 and 0.7 ppm respectively and reduced the initial turbidity to 7.4 NTU. Conclusions: The results of this study showed that using natural coagulant aid reduce the chemical coagulant consumption, and also does not have significant effect on pH range and reduce the health risks. While huge amount of required polyelectrolytes for water treatment plant imported to the country and the production of corn starch in our country is high, it is hope that the results of this project can be used in industrial scale.

Characterization of Corn Starch Films Reinforced with CaCO3 Nanoparticles

Science.gov (United States)

Sun, Qingjie; Xi, Tingting; Li, Ying; Xiong, Liu

2014-01-01

The characterization of corn starch (CS) films impregnated with CaCO3 nanoparticles was investigated. Criteria such as morphology, crystallinity, water vapor permeability (WVP), opacity, and mechanical properties were the focus of the investigation. It was found that the CaCO3 contents had significant effects on the tensile properties of the nanocomposite films. The addition of CaCO3 nanoparticles to the CS films significantly increased tensile strength from 1.40 to 2.24 MPa, elongation from 79.21 to 118.98%, and Young’s modulus from 1.82 to 2.41 MPa. The incorporation of CaCO3 nanoparticles increased the opacity of films, lowered the degree of WVP and film solubility value compared to those of the CS films. The results of scanning electron microscopy (SEM) showed that with the increase of CaCO3 nanoparticles content in starch films, the roughness of the films increased, and pores or cavities were found on the surface of the films, while small cracks were observed in the structures of the fractured surfaces. X-ray diffraction showed that the addition of nanoparticles increased the peaks in the intensity of films. PMID:25188503

Characterization of chestnut (Castanea sativa, mill starch for industrial utilization

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Demiate Ivo Mottin

2001-01-01

Full Text Available Studies were conducted to characterize the chestnut and its starch. Chemical composition of the chestnuts showed high level of starch. Moisture level in the raw nuts was around 50g/100g in wet basis and starch content, around 80g/100g in dry basis; other nut flour components were protein (5.58 g/100g, lipid (5.39 g/100g, crude fiber (2.34 g/100g and ash (2.14 g/100g. Starch fraction was chemically characterized in order to identify the granule quality as compared with those of cassava and corn. This fraction showed more lipids and proteins than the other starches. Chestnut starch granules showed peculiar shape, smaller than the control starches and low amount of damaged units. Chemical composition concerning amylose : amylopectin ratio was intermediate to that presented by cassava and corn starch granules. Water absorption at different temperatures as well as solubility were also intermediate but closer to that presented by cassava granules. The same behavior was observed in the interaction with dimethyl-sulfoxide. Native starch granules and those submitted to enzymatic treatment with commercial alpha-amylase and also with enzymes from germinated wheat were observed by scanning electronic microscopy. Water suspensions of chestnut starch granules were heated to form pastes that were studied comparatively to those obtained with cassava and corn starches. Viscographic pattern of chestnut starch pastes showed a characteristic profile with high initial viscosity but peak absence, high resistance to mechanical stirring under hot conditions and high final viscosity. There was no way to compare it with the paste viscographic profiles obtained with the control starches. Chestnut starch pastes were stable down to pH 4 but unstable at pH 3. The water losses observed in the chestnut starch pastes after freeze-thaw cycles showed more similarity to the pattern observed in corn starch pastes as well as clarity and strength of the gel. In general the results

Application of radiation technology in starch modification

International Nuclear Information System (INIS)

Chen Huiyuan; Peng Zhigang; Ding Zhongmin; Lu Jiajiu

2007-01-01

In order to commercialize the radiation modification of starch, corn starch was irradiated with different dose of 60 Co gamma radiations. Some basic physical and chemical properties of the resulted modified starch paste were measured with emphasis on the viscosity stability and tensile strength. The results indicate that irradiation of corn starch with a dose of 4-10 kGy can decrease its viscosity to 5-14 mPa·s, and the tensile strength can meet the standard set up for textile paste. In comparison with chemical modification for starch, radiation modification is simpler in technology, more convenient in operation, more stable in modification quality, and easier to control. The mechanism of radiation modification of starch was also discussed. (authors)

Thermoplastic starch materials prepared from rice starch

International Nuclear Information System (INIS)

Pontes, Barbara R.B.; Curvelo, Antonio A.S.

2009-01-01

Rice starch is a source still little studied for the preparation of thermoplastic materials. However, its characteristics, such as the presence of proteins, fats and fibers may turn into thermoplastics with a better performance. The present study intends the evaluation of the viability of making starch thermoplastic from rice starch and glycerol as plasticizer. The results of X-ray diffraction and scanning electronic microscopy demonstrate the thermoplastic acquisition. The increase of plasticizer content brings on more hydrophilic thermoplastics with less resistance to tension and elongation at break. (author)

Production of Starch Based Bioplastic from Cassava Peel Reinforced with Microcrystalline Celllulose Avicel PH101 Using Sorbitol as Plasticizer

Science.gov (United States)

Maulida; Siagian, M.; Tarigan, P.

2016-04-01

The production of starch based bioplastics from cassava peel reeinforced with microcrystalline cellulose using sorbitol as plasticizer were investigated. Physical properties of bioplastics were determined by density, water uptake, tensile strength and Fourier Transform Infrared Spectroscopy. Bioplastics were prepared from cassava peel starch plasticized using sorbitol with variation of 20; 25; 30% (wt/v of sorbitol to starch) reinforced with microcrystalline celllulose (MCC) Avicel PH101 fillers with range of 0 to 6% (wt/wt of MCC to starch). The results showed improvement in tensile strength with higher MCC content up to 9, 12 mpa compared to non-reinforced bioplastics. This could be mainly attributed to the strong hydrogen bonds between MCC and starch. On the contrary, the addition of MCC decreased the elongation at break, density and water uptake. Fourier Transform Infrared Spectroscopy showed the functional groups of bioplastics, which the majority of O-H groups were found at the bioplastics with reinforcing filler MCC that represented substantial hydrogen bonds. The highest tensile strength value was obtained for bioplastic with MCC content 6% and sorbitol content 20%. With good adhesion between MCC and starch the production of bioplastics could be widely used as a substitute for conventional plastics with more benefits to the environment.

Production of Starch Based Bioplastic from Cassava Peel Reinforced with Microcrystalline Celllulose Avicel PH101 Using Sorbitol as Plasticizer

International Nuclear Information System (INIS)

Maulida; Siagian, M; Tarigan, P

2016-01-01

The production of starch based bioplastics from cassava peel reeinforced with microcrystalline cellulose using sorbitol as plasticizer were investigated. Physical properties of bioplastics were determined by density, water uptake, tensile strength and Fourier Transform Infrared Spectroscopy. Bioplastics were prepared from cassava peel starch plasticized using sorbitol with variation of 20; 25; 30% (wt/v of sorbitol to starch) reinforced with microcrystalline celllulose (MCC) Avicel PH101 fillers with range of 0 to 6% (wt/wt of MCC to starch). The results showed improvement in tensile strength with higher MCC content up to 9, 12 mpa compared to non-reinforced bioplastics. This could be mainly attributed to the strong hydrogen bonds between MCC and starch. On the contrary, the addition of MCC decreased the elongation at break, density and water uptake. Fourier Transform Infrared Spectroscopy showed the functional groups of bioplastics, which the majority of O-H groups were found at the bioplastics with reinforcing filler MCC that represented substantial hydrogen bonds. The highest tensile strength value was obtained for bioplastic with MCC content 6% and sorbitol content 20%. With good adhesion between MCC and starch the production of bioplastics could be widely used as a substitute for conventional plastics with more benefits to the environment. (paper)

Determining the Cost of Producing Ethanol from Corn Starch and Lignocellulosic Feedstocks

Energy Technology Data Exchange (ETDEWEB)

McAloon, A.; Taylor, F.; Yee, W.; Ibsen, K.; Wooley, R.

2000-10-25

The mature corn-to-ethanol industry has many similarities to the emerging lignocellulose-to-ethanol industry. It is certainly possible that some of the early practitioners of this new technology will be the current corn ethanol producers. In order to begin to explore synergies between the two industries, a joint project between two agencies responsible for aiding these technologies in the Federal government was established. This joint project of the USDA-ARS and DOE/NREL looked at the two processes on a similar process design and engineering basis, and will eventually explore ways to combine them. This report describes the comparison of the processes, each producing 25 million annual gallons of fuel ethanol. This paper attempts to compare the two processes as mature technologies, which requires assuming that the technology improvements needed to make the lignocellulosic process commercializable are achieved, and enough plants have been built to make the design well-understood. Ass umptions about yield and design improvements possible from continued research were made for the emerging lignocellulose process. In order to compare the lignocellulose-to-ethanol process costs with the commercial corn-to-ethanol costs, it was assumed that the lignocellulose plant was an Nth generation plant, built after the industry had been sufficiently established to eliminate first-of-a-kind costs. This places the lignocellulose plant costs on a similar level with the current, established corn ethanol industry, whose costs are well known. The resulting costs of producing 25 million annual gallons of fuel ethanol from each process were determined. The figure below shows the production cost breakdown for each process. The largest cost contributor in the corn starch process is the feedstock; for the lignocellulosic process it is the capital cost, which is represented by depreciation cost on an annual basis.

Effect of irradiation on sweet corn preservation

International Nuclear Information System (INIS)

Fu Junjie

2002-01-01

60 Co γ-ray was used to irradiate newly-harvested sweet corn and the results showed that the effects of irradiation on soluble solids, sucrose, starch and total sugar were not significant. The viscosity of starch decreased with the increasing of irradiation dose. The preservation duration of irradiated sweet corn was 7 days longer than that of CK, and the sweet, smell, taste of sweet corn had no abnormal change

Effects of partial replacement of dietary starch from barley or corn with lactose on ruminal function, short-chain fatty acid absorption, nitrogen utilization, and production performance of dairy cows.

Science.gov (United States)

Chibisa, G E; Gorka, P; Penner, G B; Berthiaume, R; Mutsvangwa, T

2015-04-01

In cows fed diets based on corn-alfalfa silage, replacing starch with sugar improves milk production. Although the rate of ruminal fermentation of sugar is more rapid than that of starch, evidence has been found that feeding sugar as a partial replacement for starch does not negatively affect ruminal pH despite increasing diet fermentability. The mechanism(s) for this desirable response are unknown. Our objective was to determine the effects of replacing barley or corn starch with lactose (as dried whey permeate; DWP) on ruminal function, short-chain fatty acid (SCFA) absorption, and nitrogen (N) utilization in dairy cows. Eight lactating cows were used in a replicated 4 × 4 Latin square design with 28-d periods and source of starch (barley vs. corn) and level of DWP (0 vs. 6%, DM basis) as treatment factors. Four cows in 1 Latin square were ruminally cannulated for the measurement of ruminal function, SCFA absorption, and N utilization. Dry matter intake and milk and milk component yields did not differ with diet. The dietary addition of DWP tended to increase ruminal butyrate concentration (13.6 vs. 12.2 mmol/L), and increased the Cl(-)-competitive absorption rates for acetate and propionate. There was no sugar effect on minimum ruminal pH, and the duration and area when ruminal pH was below 5.8. Minimum ruminal pH tended to be lower in cows fed barley compared with those fed corn (5.47 vs. 5.61). The duration when ruminal pH was below pH 5.8 tended to be shorter (186 vs. 235 min/d), whereas the area (pH × min/d) that pH was below 5.8 was smaller (47 vs. 111) on the corn than barley diets. Cows fed the high- compared with the low-sugar diet had lower ruminal NH3-N concentration. Feeding the high-sugar diet tended to increase apparent total-tract digestibility of dry matter and organic matters and increased apparent total-tract digestibility of fat. Apparent total-tract digestibility of N tended to be greater in cows fed barley compared with those fed corn

Development of thermoplastic starch blown film by incorporating plasticized chitosan.

Science.gov (United States)

Dang, Khanh Minh; Yoksan, Rangrong

2015-01-22

The objective of the present work was to improve blown film extrusion processability and properties of thermoplastic starch (TPS) film by incorporating plasticized chitosan, with a content of 0.37-1.45%. The effects of chitosan on extrusion processability and melt flow ability of TPS, as well as that on appearance, optical properties, thermal properties, viscoelastic properties and tensile properties of the films were investigated. The possible interactions between chitosan and starch molecules were evaluated by FTIR and XRD techniques. Chitosan and starch molecules could interact via hydrogen bonds, as confirmed from the blue shift of OH bands and the reduction of V-type crystal formation. Although the incorporation of chitosan caused decreased extensibility and melt flow ability, as well as increased yellowness and opacity, the films possessed better extrusion processability, increased tensile strength, rigidity, thermal stability and UV absorption, as well as reduced water absorption and surface stickiness. The obtained TPS/chitosan-based films offer real potential application in the food industry, e.g. as edible films. Copyright © 2014 Elsevier Ltd. All rights reserved.

Preparation and properties of thermoplastic poly(caprolactone) composites containing high amount of esterified starch without plasticizer.

Science.gov (United States)

Sun, Yujie; Hu, Qiongen; Qian, Jiangtao; Li, Ting; Ma, Piming; Shi, Dongjian; Dong, Weifu; Chen, Mingqing

2016-03-30

Based on stearyl chloride and native starch, esterified starch were prepared and the chemical structure was characterized by (1)H NMR and FTIR. It was found that stearyl chloride was an efficient agent to fabricate esterified starch with high degree of substitution (DS). During the melt blending of esterified starch (80 wt%) and poly(caprolactone) (PCL, 20 wt%), it was shown the torque of PCL/esterified starch was much lower than that of PCL/native starch without any plasticizer, and further decreased with increasing DS. Compared with PCL/native starch, the tensile properties of PCL/esterified starch composites were significantly enhanced. The tensile strength and elongation at break were increased from 2.7 MPa to 56% for PCL/native starch composites to 9.1 MPa and 626% for PCL/esterified starch ones with DS of 1.50, respectively. SEM observation revealed the esterified starch particles in matrix became smaller and more uniform. In addition, the water resistance and hydrophobic character of PCL/esterified starch composites were improved. PCL composites containing 80 wt% esterified starch with favorable mechanical properties would have great potential applications in broad areas. Copyright © 2015 Elsevier Ltd. All rights reserved.

Preparation and properties of blends composed of lignosulfonated layered double hydroxide/plasticized starch and thermoplastics.

Science.gov (United States)

Privas, Edwige; Leroux, Fabrice; Navard, Patrick

2013-07-01

Layered double hydroxide prepared with lignosulfonate (LDH/LS) can be easily dispersed down to the nanometric scale in thermoplastic starch, at concentration of 1 up to 4 wt% of LDH/LS. They can thus be used as a bio-based reinforcing agent of thermoplastic starch. Incorporation of LDH/LS in starch must be done using LDH/LS slurry instead of powder on order to avoid secondary particles aggregation, the water of the paste being used as the starch plasticizer. This reinforced starch was used for preparing a starch-polyolefine composite. LDH/LS-starch nanocomposites were mixed in a random terpolymer of ethylene, butyl acrylate (6%) and maleic anhydride (3%) at concentrations of 20 wt% and 40 wt%. With a 20% loading of (1 wt% LDH/LS in thermoplastic starch), the ternary copolymer is partially bio-based while keeping nearly its original processability and mechanical properties and improving oxygen barrier properties. The use of layered double hydroxides is also removing most odours linked to the lignin phase. Copyright © 2013 Elsevier Ltd. All rights reserved.

Modification of water absorption capacity of a plastic based on bean protein using gamma irradiated starches as additives

International Nuclear Information System (INIS)

Koeber, E.; Gonzalez, M.E.; Gavioli, N.; Salmoral, E.M.

2007-01-01

Some properties of a bean protein-starch plastic were modified by irradiation of the starch. Two kinds of starch from bean and cassava were irradiated with doses until 50 kGy before their inclusion in the composite. Water absorption of the resultant product was reduced by 36% and 60% in materials containing bean and cassava starch, respectively. A large decline in the elongation is observed till 10 kGy in both materials, while tensile strength diminished by 11% in the cassava composite

Utilization of mango seed starch in manufacture of bioplastic reinforced with microparticle clay using glycerol as plasticizer

Science.gov (United States)

Maulida; Kartika, T.; Harahap, M. B.; Ginting, M. H. S.

2018-02-01

Bioplastics are plastics that can be used just like conventional plastics but will disintegrate by the activity of microorganisms into water and carbon dioxide. Starch is a natural polymer material that can used for bioplastic production. The addition of reinforcing particles has been shown to improve the mechanical properties of bioplastics. The aim of this research is to know the potency of mango seed starch and microparticle clay as filler and glycerol concentration as plasticizer on tensile strength and elongation at break, functional group (FTIR) and surface morphology (SEM). In this study used mango seed starch size of 5 grams, with the variation of clay filler mass of 0; 3; 6 and nine wt%, while the mass of glycerol with a variation of 0; 20; 25; 30; And 35% wt. The heating temperature of the bioplastics solution used was 80.53 °C. The resulting bioplastics was analyzed for their physical and chemical properties, including FTIR, SEM, tensile strength, elongation at break. The FTIR analysis shows that no new functional groups was formed. From the analysis of mango starch content obtained 62.82%, 44.0% amylopectin content, amylose content 14.82%, and water content 12.65%. In this study obtained bioplastics with the best conditions on the use of 6% clay and 25% glycerol, with a tensile strength of 5.657MPa, percent elongation at breakup 43.431%.

Measurement of Thermal Properties of Triticale Starch Films Using Photothermal Techniques

Science.gov (United States)

Correa-Pacheco, Z. N.; Cruz-Orea, A.; Jiménez-Pérez, J. L.; Solorzano-Ojeda, S. C.; Tramón-Pregnan, C. L.

2015-06-01

Nowadays, several commercially biodegradable materials have been developed with mechanical properties similar to those of conventional petrochemical-based polymers. These materials are made from renewable sources such as starch, cellulose, corn, and molasses, being very attractive for numerous applications in the plastics, food, and paper industries, among others. Starches from maize, rice, wheat, and potato are used in the food industry. However, other types of starches are not used due to their low protein content, such as triticale. In this study, starch films, processed using a single screw extruder with different compositions, were thermally and structurally characterized. The thermal diffusivity, thermal effusivity, and thermal conductivity of the biodegradable films were determined using photothermal techniques. The thermal diffusivity was measured using the open photoacoustic cell technique, and the thermal effusivity was obtained by the photopyroelectric technique in an inverse configuration. The results showed differences in thermal properties for the films. Also, the films microstructures were observed by scanning electron microscopy, transmission electron microscopy, and the crystalline structure determined by X-ray diffraction.

Utilization starch of jackfruit seed (Artocarpus heterophyllus) as raw material for bioplastics manufacturing using sorbitol as plasticizer and chitosan as filler

Science.gov (United States)

Lubis, M.; Harahap, M. B.; Manullang, A.; Alfarodo; Ginting, M. H. S.; Sartika, M.

2017-01-01

Starch is a natural polymer that can be used for the production of bioplastics because its source is abundant, renewable and easily degraded. Jackfruit seeds can be used as raw material for bioplastics because its contains starch. The aim of this study to determine the characteristics of jackfruit seeds and determine the effect of chitosan and sorbitol on the physicochemical properties of bioplastics from jackfruit seeds. Starch is extracted from jackfruit seeds were then characterized to determine its chemical composition. In the manufacture of bioplastics starch composition jackfruit seeds - chitosan used was 7: 3, 8: 2 and 9: 1 (g/g), while the concentration of sorbitol used was 20%, 25%, 30%, 35%, and 40% by weight dry ingredients. From the analysis of jackfruit seed starch obtained water content of 6.04%, ash content of 1.08%, the starch content of 70.22%, 16.39% amylose content, amylopectin content of 53.83%, 4.68% protein content, fat content 0.54%. The best conditions of starch bioplastics jackfruit seeds obtained at a ratio of starch: chitosan (w/w) = 8: 2 and the concentration of plasticizer sorbitol 25% with tensile strength 13.524 MPa. From the results of FT-IR analysis indicated an increase for the OH group and the group NH on bioplastics due to the addition of chitosan and sorbitol. The results of mechanical tests is further supported by analysis of scanning electron microscopy (SEM) showing jackfruit seed starch has a small granule size with the size of 7.6 μm and in bioplastics with chitosan filler and plasticizer sorbitol their fracture surface is smooth and slightly hollow compared bioplastics without fillers chitosan and plasticizer sorbitol.

Effects of Sorghum [Sorghum bicolor (L. Moench] Crude Extracts on Starch Digestibility, Estimated Glycemic Index (EGI, and Resistant Starch (RS Contents of Porridges

Directory of Open Access Journals (Sweden)

Dilek Lemlioglu-Austin

2012-09-01

Full Text Available Bran extracts (70% aqueous acetone of specialty sorghum varieties (tannin, black, and black with tannin were used to investigate the effects of sorghum phenolic compounds on starch digestibility, Estimated Glycemic Index (EGI, and Resistant Starch (RS of porridges made with normal corn starch, enzyme resistant high amylose corn starch, and ground whole sorghum flours. Porridges were cooked with bran extracts in a Rapid Visco-analyser (RVA. The cooking trials indicated that bran extracts of phenolic-rich sorghum varieties significantly reduced EGI, and increased RS contents of porridges. Thus, there could be potential health benefits associated with the incorporation of phenolic-rich sorghum bran extracts into foods to slow starch digestion and increase RS content.

Cross-Linked Amylose Bio-Plastic: A Transgenic-Based Compostable Plastic Alternative

Directory of Open Access Journals (Sweden)

Domenico Sagnelli

2017-09-01

Full Text Available Bio-plastics and bio-materials are composed of natural or biomass derived polymers, offering solutions to solve immediate environmental issues. Polysaccharide-based bio-plastics represent important alternatives to conventional plastic because of their intrinsic biodegradable nature. Amylose-only (AO, an engineered barley starch with 99% amylose, was tested to produce cross-linked all-natural bioplastic using normal barley starch as a control. Glycerol was used as plasticizer and citrate cross-linking was used to improve the mechanical properties of cross-linked AO starch extrudates. Extrusion converted the control starch from A-type to Vh- and B-type crystals, showing a complete melting of the starch crystals in the raw starch granules. The cross-linked AO and control starch specimens displayed an additional wide-angle diffraction reflection. Phospholipids complexed with Vh-type single helices constituted an integrated part of the AO starch specimens. Gas permeability tests of selected starch-based prototypes demonstrated properties comparable to that of commercial Mater-Bi© plastic. The cross-linked AO prototypes had composting characteristics not different from the control, indicating that the modified starch behaves the same as normal starch. The data shows the feasibility of producing all-natural bioplastic using designer starch as raw material.

Cross-Linked Amylose Bio-Plastic: A Transgenic-Based Compostable Plastic Alternative

Science.gov (United States)

Sagnelli, Domenico; Kemmer, Gerdi Christine; Holse, Mette; Hebelstrup, Kim H.; Bao, Jinsong; Stelte, Wolfgang; Bjerre, Anne-Belinda; Blennow, Andreas

2017-01-01

Bio-plastics and bio-materials are composed of natural or biomass derived polymers, offering solutions to solve immediate environmental issues. Polysaccharide-based bio-plastics represent important alternatives to conventional plastic because of their intrinsic biodegradable nature. Amylose-only (AO), an engineered barley starch with 99% amylose, was tested to produce cross-linked all-natural bioplastic using normal barley starch as a control. Glycerol was used as plasticizer and citrate cross-linking was used to improve the mechanical properties of cross-linked AO starch extrudates. Extrusion converted the control starch from A-type to Vh- and B-type crystals, showing a complete melting of the starch crystals in the raw starch granules. The cross-linked AO and control starch specimens displayed an additional wide-angle diffraction reflection. Phospholipids complexed with Vh-type single helices constituted an integrated part of the AO starch specimens. Gas permeability tests of selected starch-based prototypes demonstrated properties comparable to that of commercial Mater-Bi© plastic. The cross-linked AO prototypes had composting characteristics not different from the control, indicating that the modified starch behaves the same as normal starch. The data shows the feasibility of producing all-natural bioplastic using designer starch as raw material. PMID:28973963

Cross-Linked Amylose Bio-Plastic: A Transgenic-Based Compostable Plastic Alternative.

Science.gov (United States)

Sagnelli, Domenico; Hooshmand, Kourosh; Kemmer, Gerdi Christine; Kirkensgaard, Jacob J K; Mortensen, Kell; Giosafatto, Concetta Valeria L; Holse, Mette; Hebelstrup, Kim H; Bao, Jinsong; Stelte, Wolfgang; Bjerre, Anne-Belinda; Blennow, Andreas

2017-09-30

Bio-plastics and bio-materials are composed of natural or biomass derived polymers, offering solutions to solve immediate environmental issues. Polysaccharide-based bio-plastics represent important alternatives to conventional plastic because of their intrinsic biodegradable nature. Amylose-only (AO), an engineered barley starch with 99% amylose, was tested to produce cross-linked all-natural bioplastic using normal barley starch as a control. Glycerol was used as plasticizer and citrate cross-linking was used to improve the mechanical properties of cross-linked AO starch extrudates. Extrusion converted the control starch from A-type to Vh- and B-type crystals, showing a complete melting of the starch crystals in the raw starch granules. The cross-linked AO and control starch specimens displayed an additional wide-angle diffraction reflection. Phospholipids complexed with Vh-type single helices constituted an integrated part of the AO starch specimens. Gas permeability tests of selected starch-based prototypes demonstrated properties comparable to that of commercial Mater-Bi © plastic. The cross-linked AO prototypes had composting characteristics not different from the control, indicating that the modified starch behaves the same as normal starch. The data shows the feasibility of producing all-natural bioplastic using designer starch as raw material.

Bioplastic from Chitosan and Yellow Pumpkin Starch with Castor Oil as Plasticizer

Science.gov (United States)

Hasan, M.; Rahmayani, R. F. I.; Munandar

2018-03-01

This study has been conducted on bioplastic synthesis of chitosan and yellow pumpkin starch (Cucurbita moschata) with castor oil as plasticizer. The purpose of this study is to determine the characteristics of the effect of chitosan and starch composition of pumpkins against solvent absorption, tensile strength and biodegradable. The first stage of the research is the making of bioplastic by blending yellow pumpkin starch, chitosan and castor oil. Further, it tested the absorption capacity of the solvent, tensile strength test, and biodegradable analysis. The optimum absorption capacity of the solvent is obtained on the composition of Pumpkin/Chitosan was 50/50 in H2O and C2H5OH solvent. Meanwhile the optimum absorbency in HCl and NaOH solvents is obtained by 60/40 composition. The characterization of the optimum tensile strength test was obtained on the 40/60 composition of 6.787 ± 0.274 Mpa and the fastest biodegradation test process within 5-10 days occurred in the 50/50 composition. The more chitosan content the higher the value of tensile strength test obtained, while the fastest biodegradation rate occureds in the composition of yellow pumpkin starch and chitosan balanced 50:50.

Effect of γ-ray irradiation on alcohol production from corn

International Nuclear Information System (INIS)

Han, Y.W.; Cho, Y.K.; Ciegler, A.

1983-01-01

Cracked corn was irradiated with γ rays at 0-100 Mrad and the effects of the irradiation on sugar yield, susceptibility to enzymatic hydrolysis of starch, yeast growth, and alcohol production were studied. Gamma irradiation at 50 Mrad or greater produced a considerable amount of reducing sugar but little glucose. At lower dosages, γ irradiation significantly increased the susceptibility of corn starch to enzymatic hydrolysis, but dosages of 50 Mrad or greater decomposed the starch molecules as indicated by the reduction in iodine uptake. About 12.5% reducing sugar was produced by amylase treatment of uncooked, irradiated corn. This amount exceeded the level of sugar produced from cooked (gelatinized) corn by the same enzyme treatment. The yeast numbers in submerged cultivation were lower on a corn substrate that was irradiated at 50 Mrad or greater compared to that on an unirradiated control. About the same level of alcohol was produced on uncooked, irradiated (10 5 - 10 6 rad) corn as from cooked (121 degrees C for 30 min) corn. Therefore, the conventional cooking process for gelatinization of starch prior to its saccharification can be eliminated by irradiation. Irradiation also eliminated the necessity of sterilization of the medium and reduced the viscosity of high levels of substrate in the fermentation broth. (Refs. 10)

Impact of dietary starch concentration formulated with two types of corn silage on methane and ammonia emissions in dairy cows

Science.gov (United States)

The objective of this study was to evaluate methane (CH4) and ammonia (NH3) emissions of lactating dairy cows fed different starch level and corn silage type. After the completion of an 8-wk production study, 48 Holstein cows were allocated to 1 of 4 air-flow controlled chambers (2 cows/chamber) for...

21 CFR 184.1865 - Corn syrup.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Corn syrup. 184.1865 Section 184.1865 Food and... Substances Affirmed as GRAS § 184.1865 Corn syrup. (a) Corn syrup, commonly called “glucose sirup” or “glucose syrup,” is obtained by partial hydrolysis of corn starch with safe and suitable acids or enzymes...

Porous HA-Al2O3 composite characterization using corn starch as a porogen agent

International Nuclear Information System (INIS)

Silva, L.A.J. da; Galdino, A.G.S.; Cardoso, G.B.C.; Zavaglia, C.A.C.

2011-01-01

The porous ceramics based on hydroxyapatite have great potential for application in bone grafts due to its chemical similarity with the mineral phase of bone tissue, but have poor biomechanical properties, which cause limitations in its applications. This work aims to analyze the structural characteristics of porous ceramics obtained by addition of hydroxyapatite (HA, sintered in the laboratory), Corn Starch (CS, commercial) and Al 2 O 3 (ALCOA), at different temperatures. Samples were made of dense HA (100% HA), porous (70% HA - 30% CS) and with addition of 2.5%, 5% and 7.5% Al 2 O 3 porous composition. The samples were sintered at 1250°C, 1300 deg C and 135 0°C and characterized by: XRF, XRD, SEM and density by the Archimedes method. Concludes It is the possibility of obtaining samples porous HA / Al 2 O 3 using starch as porogenic agent. The temperature and concentration of Al 2 O 3 most appropriate were: 1250°C and 7.5%. (author)

New strategy for enhancement of microbial viability in simulated gastric conditions based on display of starch-binding domain on cell surface.

Science.gov (United States)

Tarahomjoo, Shirin; Katakura, Yoshio; Shioya, Suteaki

2008-05-01

The C-terminal region of the peptidoglycan hydrolase (CPH) of Lactococcus lactis IL1403 fused to the linker region and the starch-binding domain (SBD) of the *-amylase of Streptococcus bovis 148 was produced intracellularly in Escherichia coli. The fusion protein (CPH-SBD) was able to bind to the cell surface of Lactobacillus casei NRRL B-441 and to corn starch. Therefore, adhesion of cells to corn starch was mediated by the fusion protein. At a cell density of 10(9) cfu/ml and a starch concentration of 5 mg/ml, CPH-SBD-displaying L. casei cells aggregated with corn starch, whereas the free cells of L. casei did not form any aggregates with corn starch. After incubation in simulated gastric juice (pH 3.0, 1 h), the survival percentages of free cells, amylose-coated free cells, and free cells mixed with corn starch were 0.074%, 7.2%, and 3.1% respectively. When CPH-SBD-displaying bacteria aggregated with corn starch, their survival percentage was 8% higher than that of free cells mixed with corn starch. The survival of the amylose-coated CPH-SBD-displaying L. casei cells was comparable to that of amylose-coated free cells, whereas the survival percentage of amylose-coated aggregates of CPH-SBD-displaying bacteria with corn starch was 28% higher than that of amylose-coated mixture of free cells with corn starch. These results demonstrate the potential usefulness of the cell-surface display technique for enhancement of the delivery of viable microorganisms to the intestinal tract.

Effect of plasticization on the conductivity and dielectric properties of starch-chitosan blend biopolymer electrolytes infused with NH4Br

Science.gov (United States)

Shukur, M. F.; Majid, N. A.; Ithnin, R.; Kadir, M. F. Z.

2013-11-01

The present work examines the effect of plasticization on the conductivity and dielectric properties of starch-chitosan blend biopolymer electrolytes. Initial Fourier transform infrared (FTIR) spectroscopy analysis of the hydroxyl band recorded 3280 cm-1 for starch and 3354 cm-1 for chitosan. The FTIR spectrum of starch-chitosan blend films shows that the hydroxyl band shifted to 3288 cm-1, indicating interaction between pure starch and chitosan. Different concentrations of ammonium bromide (NH4Br) were then added to the blend solution and stirred until complete dissolution. The homogeneous solutions were then placed onto different plastic Petri dishes, where they were left to dry. The highest conductivity value of (9.72 ± 0.95) × 10-5 S cm-1 was obtained with addition of 35 wt% NH4Br. Addition of 30 wt% ethylene carbonate increased the conductivity value to (1.44 ± 0.51) × 10-3 S cm-1. The plots of dielectric constant, ɛr, against frequency for both plasticized and unplasticized systems show non-Debye behaviour. The temperature dependence of the power law exponent for the highest conducting sample in the unplasticized system follows the small polaron hopping model while the conduction mechanism of the highest conducting sample in the plasticized system can be represented by the quantum mechanical tunnelling model.

Development of a CO2 -releasing coformulation based on starch, Saccharomyces cerevisiae and Beauveria bassiana attractive towards western corn rootworm larvae.

Science.gov (United States)

Vemmer, Marina; Schumann, Mario; Beitzen-Heineke, Wilhelm; French, Bryan W; Vidal, Stefan; Patel, Anant V

2016-11-01

CO 2 is known as an attractant for many soil-dwelling pests. To implement an attract-and-kill strategy for soil pest control, CO 2 -emitting formulations need to be developed. The aim of the present work was to develop a slow-release bead system in order to bridge the gap between application and hatching of western corn rootworm larvae. We compared different Ca-alginate beads containing Saccharomyces cerevisiae for their potential to release CO 2 over a period of several weeks. The addition of starch improved CO 2 release, resulting in significantly higher CO 2 concentrations in soil for at least 4 weeks. The missing amylase activity was compensated for either by microorganisms present in the soil or by coencapsulation of Beauveria bassiana. Formulations containing S. cerevisiae, starch and B. bassiana were attractive for western corn rootworm larvae within the first 4 h following exposure; however, when considering the whole testing period, the maize root systems remained more attractive for the larvae. Coencapsulation of S. cerevisiae, starch and B. bassiana is a promising approach for the development of attractive formulations for soil applications. For biological control strategies, the attractiveness needs to be increased by phagostimuli to extend contact between larvae and the entomopathogenic fungus growing out of these formulations. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

BIODEGRADABLE PLASTICS FROM A MIXTURE OF LOW DENSITY POLYETHYLENE (LDPE AND CASSAVA STARCH WITH THE ADDITION OF ACRYLIC ACID

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Susilawati Susilawati

2013-05-01

Full Text Available A research of preparation biodegradable plastics, from LDPE and cassava starch mixture with the addition of acrylic acid, had been conducted. This research purpose to  studied compatibility properties of the material and percent weight loss during the biodegradation test. Optimum weight loss (59,26% was showed after 60 days witches LDPE and starch composition ratio 6 : 4 (w/w  while tensile strength  equal to 0,38 Kgf/mm2.  SEM characterization showed that biodegradation has occurred by  formation of hole in the biodegradable plastic surface. DTA test gave Tg = 130 °C, Tm = 230 °C and Td = 370-450 °C while FT-IR analysis showed that the biodegradable plastics have a chemistry interaction.

Enzymic conversion of starch to glucose

Energy Technology Data Exchange (ETDEWEB)

1964-08-19

Corn is steeped in a SO/sub 2/ solution for 30 to 40 hours, coarsely ground, separated from the germ, and filtered. A 35% suspension of the germ-free corn, still containing fibers, hull, and gluten, is treated with Ca(OH)/sub 2/ to raise the pH to 6.5 to 7.0. A starch-liquifying enzyme is added and after a 2 hours treatment at 85/sup 0/ the liquefied starch is cooled to 60/sup 0/ and the pH is adjusted to 4.5 to 5.0 with H/sub 2/SO/sub 4/. A saccharifying enzyme is now added. After 40 to 81 hours, a raw glucose solution is obtained and is freed from fibers and gluten by filtration. The commercial starch-liquifying enzymes are designated HT-1000 and Neozyme 3 LC (liquid). The saccharifying enzymes are Diazyme or Diazyme L 30 (liquid). The solid enzymes are used at a level up to 0.1% by weight of the starch. Up to 100% conversion of starch into glucose is achieved.

Optimization of polyhydroxybutyrate production by Bacillus sp. CFR 256 with corn steep liquor as a nitrogen source

OpenAIRE

Vijayendra, S. V. N.; Rastogi, N. K.; Shamala, T. R.; Anil Kumar, P. K.; Kshama, L.; Joshi, G. J.

2007-01-01

Polyhydroxyalkanotes (PHAs), the eco-friendly biopolymers produced by many bacteria, are gaining importance in curtailing the environmental pollution by replacing the non-biodegradable plastics derived from petroleum. The present study was carried out to economize the polyhydroxybutyrate (PHB) production by optimizing the fermentation medium using corn steep liquor (CSL), a by-product of starch processing industry, as a cheap nitrogen source, by Bacillus sp. CFR 256. Response surface methodol...

21 CFR 184.1857 - Corn sugar.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Corn sugar. 184.1857 Section 184.1857 Food and... Substances Affirmed as GRAS § 184.1857 Corn sugar. (a) Corn sugar (C6H12O6, CAS Reg. No. 50-99-7), commonly... monohydrate form and is produced by the complete hydrolysis of corn starch with safe and suitable acids or...

The effect of acid hydrolysis on the technological functional properties of pinhão (Araucaria brasiliensis starch

Directory of Open Access Journals (Sweden)

Roberta Cruz Silveira Thys

2013-02-01

Full Text Available Technological functional properties of native and acid-thinned pinhão (seeds of Araucária angustifolia, Brazilian pine starches were evaluated and compared to those of native and acid-thinned corn starches. The starches were hydrolyzed (3.2 mol.L-1 HCl, 44 ºC, 6 hours and evaluated before and after the hydrolysis reaction in terms of formation, melting point and thermo-reversibility of gel starches, retrogradation (in a 30-day period and measurements every three days, paste freezing and thawing stability (after six freezing and thawing cycles, swelling power, and solubility. The results of light transmittance (% of pastes of native and acid-thinned pinhão starches was higher (lower tendency to retrogradation than that obtained for corn starches after similar storage period. Native pinhão starch (NPS presented lower syneresis than native corn starch (NCS when submitted to freeze-thaw cycles. The acid hydrolysis increased the syneresis of the two native varieties under storage at 5 ºC and after freezing and thawing cycles. The solubility of NPS was lower than that of native corn starch at 25, 50, and 70 ºC. However, for the acid-thinned pinhão starch (APS, this property was significantly higher (p < 0.05 when compared to that of acid-thinned corn starch (ACS. From the results obtained, it can be said that the acid treatment was efficient in producing a potential fat substitute from pinhão starch variety, but this ability must be further investigated.

Production and characterization of bio plastics from potato starch, poly-hydroxybutyrate and poly-hydroxybutyrate-co-valerate

International Nuclear Information System (INIS)

Mendes, Fernanda M.; Curvelo, Antonio A.S.

2009-01-01

This work describes the study of thermoplastic starch (TPS) blends obtained from potato starch (plasticised with glycerol) with biodegradable polymers poly-hydroxybutyrate (PHB) and poly-hydroxybutyrate-co-valerate (PHB V). For this purpose it were developed several formulations with TPS/PHB, TPS/PHB V and TPS/PHB/PHB V prepared by physical mixing and water and glycerol as plasticizers. The amount of glycerol was 30% based on starch (dry basis). The starting materials (starch, PHB and PHB V) were characterized by scanning electron microscopy and X-ray diffraction. Then, it was determined the optimal processing conditions for the samples, performed by using an intensive mixer. The materials were hot pressed to produce the standardized samples employed in the characterizations: mechanical testing (tensile strength), dynamic-mechanical thermal analysis (DMTA), scanning electron microscopy and X-ray diffractometry. (author)

Nano-cellulose based nano-coating biomaterial dataset using corn leaf biomass: An innovative biodegradable plant biomaterial

Directory of Open Access Journals (Sweden)

A.B.M. Sharif Hossain

2018-04-01

Full Text Available The nanocellulose derived biodegradable plant biomaterial as nano-coating can be used in the medical, biomedical cosmetics, and bioengineering products. Bio-plastic and some synthetic derived materials are edible and naturally biodegradable. The study was conducted to investigate edible nano-biopolymer based nano-coating of capsules and drugs or other definite biomedical materials from corn leaf biomass. Corn leaf biomass was used as an innovative sample to produce edible nano-coating bioplastic for drug and capsule coating and other industrial uses. The data show the negligible water 0.01% absorbed by bio-plastic nanocoating. Odor represented by burning test was under the completely standard based on ASTM. Moreover, data on color coating, tensile strength, pH, cellulose content have been shown under standard value of ASTM (American standard for testing and materials standard. In addition to that data on the chemical element test like K+, CO3−−, Cl-, Na+ exhibited positive data compared to the synthetic plastic in the laboratory using the EN (166 standardization. Therefore, it can be concluded that both organic (cellulose and starch based edible nano-coating bioplastic may be used for drug and capsule coating as biomedical and medical components in the pharmaceutical industries. Keywords: Nanocellulose, Nanobioplastic, Nanocoating, Biodegradable, Corn leaf

Starch/polyester films: simultaneous optimisation of the properties for the production of biodegradable plastic bags

Directory of Open Access Journals (Sweden)

J. B. Olivato

2013-01-01

Full Text Available Blends of starch/polyester have been of great interest in the development of biodegradable packaging. A method based on multiple responses optimisation (Desirability was used to evaluate the properties of tensile strength, perforation force, elongation and seal strength of cassava starch/poly(butylene adipate-co-terephthalate (PBAT blown films produced via a one-step reactive extrusion using tartaric acid (TA as a compatibiliser. Maximum results for all the properties were set as more desirable, with an optimal formulation being obtained which contained (55:45 starch/PBAT (88.2 wt. (%, glycerol (11.0 wt. (% and TA (0.8 wt. (%. Biodegradable plastic bags were produced using the film with this formulation, and analysed according to the standard method of the Associação Brasileira de Normas Técnicas (ABNT. The bags exhibited a 45% failure rate in free-falling dart impact tests, a 10% of failure rate in dynamic load tests and no failure in static load tests. These results meet the specifications set by the standard. Thus, the biodegradable plastic bags fabricated with an optimised formulation could be useful as an alternative to those made from non-biodegradable materials if the nominal capacity declared for this material is considered.

In situ study starch gelatinization under ultra-high hydrostatic pressure using synchrotron SAXS

KAUST Repository

Yang, Zhi

2015-12-13

The gelatinization of waxy (very low amylose) corn and potato starches by high hydrostatic pressure (HHP) (up to ∼1 GPa) was investigated in situ using synchrotron small-angle X-ray scattering (SAXS) on samples held in a diamond anvil cell (DAC). The starch pastes, made by mixing starch and water in a 1:1 ratio (by weight), were pressurized and measured at room temperature. During HHP, both SAXS peak areas (corresponding to the lamellar phase) of waxy corn and potato starches decreased suggesting the starch gelatinization increases with increasing pressure. As pressure increased, lamellar peak broadened and the power law exponent increased in low q region. 1D linear correlation function was further employed to analyse SAXS data. For both waxy potato and waxy corn starches, the long period length and the average thickness of amorphous layers decreased when the pressure increased. While for both of waxy starches, the thickness of the crystalline layer first increased, then decreased when the pressure increased. The former is probably due to the out-phasing of starch molecules, and the latter is due to the water penetrating into the crystalline region during gelatinization and to pressure induced compression.

Raw starch digestion by. alpha. -amylase and glucoamylase from Chalara paradoxa

Energy Technology Data Exchange (ETDEWEB)

Monma, Mitsura; Yamamoto, Yoshihiro; Kagei, Norio; Kainuma, Keiji

1989-10-01

Glucoamylase and {alpha}-amylase of Chalara paradoxa were separated by hydrophobic column chromatography using butyl-Toyopearl 650M. The {alpha}-amylase showed the highest activity at pH 5.5 and 45{sup 0}C, and was stable in the pH range of 5.5-6.5 and at temperatures lower than 40{sup 0}C. The glucoamylase showed the highest activity at pH 5.0 and 45{sup 0}C, and was stable in the pH range of 4.0-7.5 and at temperatures lower than 45{sup 0}C. The molecular mass of the {alpha}-amylase and glucoamylase estimated by SDS polyacrylamide gel electrophoresis was 80,000 and 68,000, respectively. Both glucoamylase and {alpha}-amylase could digest more effectively raw rice starch and raw corn starch than raw sago starch and raw potato starch. 2% raw rice starch in 10 ml solution was digested by more than 90% by 100 units of each amylase. When these amylases were used combined, raw corn starch was more effectively digested than they were used singly. This cooperative action in raw corn starch digestion was also observed when C. paradoxa {alpha}-amylase and R. niveus glucoamylase were combined. (orig.).

Strategies to improve the mechanical properties of starch-based materials: plasticization and natural fibers reinforcement

Directory of Open Access Journals (Sweden)

A. Lopez-Gil

2014-01-01

Full Text Available Biodegradable polymers are starting to be introduced as raw materials in the food-packaging market. Nevertheless, their price is very high. Starch, a fully biodegradable and bioderived polymer is a very interesting alternative due to its very low price. However, the use of starch as the polymer matrix for the production of rigid food packaging, such as trays, is limited due to its poor mechanical properties, high hidrophilicity and high density. This work presents two strategies to overcome the poor mechanical properties of starch. First, the plasticization of starch with several amounts of glycerol to produce thermoplastic starch (TPS and second, the production of biocomposites by reinforcing TPS with promising fibers, such as barley straw and grape waste. The mechanical properties obtained are compared with the values predicted by models used in the field of composites; law of mixtures, Kerner-Nielsen and Halpin-Tsai. To evaluate if the materials developed are suitable for the production of food-packaging trays, the TPS-based materials with better mechanical properties were compared with commercial grades of oil-based polymers, polypropylene (PP and polyethylene-terphthalate (PET, and a biodegradable polymer, polylactic acid (PLA.

Comparison of various types of starch when used in meat sausages.

Science.gov (United States)

Skrede, G

1989-01-01

Technological and sensory properties of meat sausages formulated with 4·0% of either potato flour, modified (acetylated distarch phosphate) potato starch, wheat, corn or tapioca starch were compared. Sausages were analyzed after cooking at temperatures between 65 and 85°C followed by storage at 5°C and -25°C. Characteristics evaluated were weight loss during cooking and storage, instrumentally and sensory assessed firmness, taste and smell of sausages. The results revealed differences in the suitability of starches for use in meat sausages. Part of the differences could be ascribed to differences in gelatination properties of the starches. With the criteria used for evaluating quality, potato flour was rated as the best suited starch followed by wheat starch while tapioca was rated as the least suited. Corn starch required cooking temperatures above 75°C and showed relatively low freeze/thaw stability. The modified potato starch stored well both above and below the freezing point. Copyright © 1989. Published by Elsevier Ltd.

Reduction of acrylamide content in bread crust by starch coating.

Science.gov (United States)

Liu, Jie; Liu, Xiaojie; Man, Yong; Liu, Yawei

2018-01-01

A technique of starch coating to reduce acrylamide content in bread crust was proposed. Bread was prepared in accordance with a conventional procedure and corn or potato starch coating was brushed on the surface of the fermented dough prior to baking. Corn starch coating caused a decrease in acrylamide of 66.7% and 77.1% for the outer and inner crust, respectively. The decrease caused by the potato starch coating was 68.4% and 77.4%, respectively. Starch coating reduced asparagine content significantly (43.4-82.9%; P coating, which effectively shortened the time span (4-8 min) over which acrylamide could form and accumulate. The present study demonstrates that starch coating could be a simple, effective and practical application for reducing acrylamide levels in bread crust without changing the texture and crust color of bread. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Modification of Sodium Release Using Porous Corn Starch and Lipoproteic Matrix.

Science.gov (United States)

Christina, Josephine; Lee, Youngsoo

2016-04-01

Excessive sodium consumption can result in hypertension, diabetes, heart diseases, stroke, and kidney diseases. Various chips and extruded snacks, where salt is mainly applied on the product surface, accounted for almost 56% of snacks retail sales in 2010. Hence, it is important to target sodium reduction for those snack products. Past studies had shown that modifying the rate-release mechanism of sodium is a promising strategy for sodium reduction in the food industry. Encapsulation of salt can be a possible technique to control sodium release rate. Porous corn starch (PCS), created by enzymatic treatment and spray drying and lipoproteic matrix, created by gelation and freeze drying, were evaluated as carriers for controlled sodium release targeting topically applied salts. Both carriers encapsulated salt and their in vitro sodium release profiles were measured using a conductivity meter. The sodium release profiles of PCS treated with different enzymatic reaction times were not significantly different. Protein content and fat content altered sodium release profile from the lipoproteic matrix. The SEM images of PCS showed that most of the salt crystals coated the starch instead of being encapsulated in the pores while the SEM images and computed tomography scan of lipoproteic matrix showed salt dispersed throughout the matrix. Hence, PCS was found to have limitations as a sodium carrier as it could not effectively encapsulate salt inside its pores. The lipoproteic matrix was found to have a potential as a sodium carrier as it could effectively encapsulate salt and modify the sodium release profile. © 2016 Institute of Food Technologists®

Starch-based Foam Composite Materials: processing and bioproducts

Science.gov (United States)

Starch is an abundant, biodegradable, renewable and low-cost commodity that has been explored as a replacement for petroleum-based plastics. By itself, starch is a poor replacement for plastics because of its moisture sensitivity and brittle properties. Efforts to improve starch properties and funct...

Hydrocolloids Decrease the Digestibility of Corn Starch, Soy Protein, and Skim Milk and the Antioxidant Capacity of Grape Juice.

Science.gov (United States)

Yi, Yue; Jeon, Hyeong-Ju; Yoon, Sun; Lee, Seung-Min

2015-12-01

Hydrocolloids have many applications in foods including their use in dysphagia diets. We aimed to evaluate whether hydrocolloids in foods affect the digestibility of starch and protein, and their effects on antioxidant capacity. The thickening hydrocolloids: locust bean gum and carboxymethyl cellulose, and the gel-forming agents: agar agar, konjac-glucomannan, and Hot & Soft Plus were blended with corn starch and soy protein, skim milk, or grape juice and were examined for their in vitro-digestability by comparing the reducing sugar and trichloroacetic acid (TCA)-soluble peptide, for antioxidant capacity by total polyphenol contents and the 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity. The hydrocolloids resulted in a decrease in starch digestibility with the gel-forming agents. Hydrocolloids diminished TCA-soluble peptides in skim milk compared to soy protein with the exception of locust bean gum and decreased free radical scavenging capacities and total phenolic contents in grape juice. Our findings may provide evidence for the use of hydro-colloids for people at risk of nutritional deficiencies such as dysphagia patients.

The effect of starch-garlic powder ratio on degradation rate of Gadung starch bioplastic

Science.gov (United States)

Mairiza, L.; Mariana; Ramadhany, M.; Feviyussa, C. A.

2018-03-01

Bioplastic is one of the solutions for environmental problems caused by plastics waste. Utilization of toxic gadung starch in the manufacturing of bioplastic would be as an alternative, due to gadung bulb has high starch content, and it is still not used optimally. This research aimed to learn about the using of gadung starch-mixed with garlic powder of making biodegradable plastic packaging. Also, to observe the duration of degradation, as a level of biodegradability of plastic film produced. The method used making this bioplastic was casting method. The variables used in this study were the ratios of starch and powdered garlic, were 10:0; 8:2; 6:4, and the concentration of garlic powder were 2%; 4%; 6%; and 8 %. The degradation test was done by soil burial test. The results of the soil burial test shown that the film was more rapidly degraded at ratio of 6: 4 compared to the ratio of 8: 2 and 10: 0. The results shown that bioplastic at the starch-garlic powder ratio of 10: 0 was decomposed in 21 days, at the the ratio of 8:2 was 15 days, while at the ratio of 6:4, the plastic film was degraded in the 11 days.

Comparative studies of starch susceptibilities to α-amylase ...

African Journals Online (AJOL)

ayoade

of the four starch samples varied; amylose content of starch from maize varieties was higher than ... plants as an energy store. ... staple foods as potatoes, wheat, maize (corn), rice and ... of its various chemical and physical properties, can be.

Study on the synthesis and physicochemical properties of starch acetate with low substitution under microwave assistance.

Science.gov (United States)

Lin, Derong; Zhou, Wei; Zhao, Jingjing; Lan, Weijie; Chen, Rongming; Li, Yutong; Xing, Baoshan; Li, Zhuohao; Xiao, Mengshi; Wu, Zhijun; Li, Xindan; Chen, Rongna; Zhang, Xingwen; Chen, Hong; Zhang, Qing; Qin, Wen; Li, Suqing

2017-10-01

In this study, synthesis and physicochemical properties of starch acetate with low substitution under microwave were studied. A three-level-three-factorial Central Composite Design using Response Surface Methodology (RSM) was employed to optimize the reaction conditions. The optimal parameters are as follows: amount of acetic anhydride of 12%, radiation time of 11min, and microwave power of 100W. These optimal conditions predicted by RSM were confirmed that the degree of substitution (DS) of acetate starch is 0.0691mg/g and the physical and chemical properties of natural corn starch (NCS) and corn starch acetate (ACS) were further studied.The transparency, water separation, water absorption, expansion force, and solubility of ACS low substitution are better than NCS, while the NCS's hydrolysis percentage is higher than ACS, which indicate that the modified corn starch has better performance than native corn starch. The surface morphology of the corn starch acetate was examined by scanning electron microscope (SEM), which showed that it had a smooth surface and a spherical and polygonal shape. However, samples' shape is irregular. Crystal structure was observed by X-ray diffraction, and the ACS can determine the level of microwave technology that can destroy the extent of the crystal and amorphous regions. Fourier transform infrared (FTIR) spectroscopy shows that around 1750cm -1 carbonyl signal determines acetylation bonding successfully. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of dietary starch source and concentration on equine fecal microbiota

Science.gov (United States)

Starch from corn is less susceptible to equine small intestinal digestion than starch from oats, and starch that reaches the hindgut can be utilized by the microbiota. The objective of the current study was to examine the effects of starch source on equine fecal microbiota. Thirty horses were assig...

Development of starch biofilms using different carboxylic acids as plasticizers; Desenvolvimento de biofilmes de amido utilizando como plastificantes diferentes acidos carboxilicos

Energy Technology Data Exchange (ETDEWEB)

Cruz, L.C.; Miranda, C.S.; Santos, W.J. dos; Goncalves, A.P.B.; Oliveira, J.C.; Jose, N.M., E-mail: uanaconceicaocruz@gmail.com [Universidade Federal da Bahia (GECIM/UFBA), Salvador, BA (Brazil). Programa de Pos-Graduacao em Engenharia Quimica. Grupo de Energia e Ciencias dos Materiais

2014-07-01

Biodegradable films have become a widely exploited issue among scientists because of their positive environmental impact, besides their potential to promote better food conservation and an increase in shelf life. Starch has been studied in this field due to its availability, low cost and biodegradability. However, starch films tend to be brittle and they need addition of a plasticizer to enable their usage. In this work, starch films were synthesized with different carboxylic acids as plasticizers, aiming to observe the effect of the acids chain size in the final films properties. The acids used were: oxalic, succinic and adipic. The materials were produced by casting and characterized by DSC, TG, DRX e FTIR. It was observed that the acids chain size influenced on the thermal and structural properties of the films. (author)

Effect of crystallinity and plasticizer on mechanical properties and tissue integration of starch-based materials from two botanical origins.

Science.gov (United States)

Velasquez, Diego; Pavon-Djavid, Graciela; Chaunier, Laurent; Meddahi-Pellé, Anne; Lourdin, Denis

2015-06-25

The application of starch-based materials for biomedical purposes has attracted significant interest due to their biocompatibility. The physical properties and crystal structure of materials based on potato starch (PS) and amylomaize starch (AMS) were studied under physiological conditions. PS plasticized with 20% glycerol presented the best mechanical properties with an elastic modulus of 1.6MPa and a weak swelling, remaining stable for 30 days. The in vitro cell viability of 3T3 cells after contact with extracts from PS and AMS with 20% glycerol is 72% and 80%, respectively. PS presented good tissue integration and no significant inflammation or foreign body response after 30 days intra-muscular implantation in a rat model, contrary to AMS. It was shown that glycerol plasticization favors a fast B-type crystallization of PS materials, enhancing their mechanical strength and durability, and making them a good candidate for bioresorbable and biocompatible materials for implantable medical devices. Copyright © 2015 Elsevier Ltd. All rights reserved.

EFFECT OF PLASTICIZERS ON MECHANICAL PROPERTIES OF EDIBLE FILM FROM JANENG STARCH – CHITOSAN

Directory of Open Access Journals (Sweden)

Narlis Juandi

2016-10-01

Full Text Available The interest in the development of edible and biodegradable films has increased because it is every day more evident that non degradable are doing much damage to the environment. In this research, edible films were based on blends of janeng starch in different proportions, added of palm oil or glycerol, which were used as plasticizers. The objective was to study the effect of two different plasticizers, palm oil and glycerol of edible film from janeng starch–chitosan on the mechanical properties and FTIR spectra. Increasing concentration of glycerol as plasticizer resulted tend to increased tensile strength and elongation at break. The tensile strength and elongation at break values for palm oil is higher than glycerol as plasticizer at the same concentration. FTIR spectra show the process of making edible film from janeng starch–chitosan with palm oil or glycerol as plasticizers are physically mixing in the presence of hydrogen interactions between chains.

Starch modification with microbial alpha-glucanotransferase enzymes

NARCIS (Netherlands)

van der Maarel, Marc J. E. C.; Leemhuis, Hans

2013-01-01

Starch is an agricultural raw material used in many food and industrial products. It is present in granules that vary in shape in the form of amylose and amylopectin. Starch-degrading enzymes are used on a large scale in the production of sweeteners (high fructose corn syrup) and concentrated

Mechanical properties and solubility in water of corn starch-collagen composite films: Effect of starch type and concentrations.

Science.gov (United States)

Wang, Kun; Wang, Wenhang; Ye, Ran; Liu, Anjun; Xiao, Jingdong; Liu, Yaowei; Zhao, Yana

2017-02-01

This study investigated the possibility of enhancing the properties of collagen with three different maize starches: waxy maize starch, normal starch, and high amylose starch. Scanning electron microscopy images revealed that starch-collagen films had a rougher surface compared to pure collagen films which became smoother upon heating. Amylose starch and normal starch increased the tensile strength of unheated collagen films in both dry and wet states, while all starches increased tensile strength of collagen film by heating. Depending upon the amylose content and starch concentrations, film solubility in water decreased with the addition of starch. DSC thermograms demonstrated that addition of all starches improved the thermal stability of the collagen film. Moreover, X-ray diffraction results indicated that except for high amylose starch, the crystallinity of both starch and collagen was significantly decreased when subject to heating. FTIR spectra indicated that intermolecular interactions between starch and collagen were enhanced upon heating. Copyright © 2016 Elsevier Ltd. All rights reserved.

The influence of starch molecular mass on the properties of extruded thermoplastic starch

NARCIS (Netherlands)

Vliegenthart, J.F.G.; Soest, J.J.G. van; Benes, K.; Wit, D. de

1996-01-01

The mechanical properties of a low and a high molecular mass thermoplastic starch (TPS) were monitored at water contents in the range of 5–30% (w/w). The granular starches were plasticized by extrusion processing with glycerol and water. The low molecular mass starch was prepared by partial acid

The effect of Gamma-irradiation on the functional properties of starch

International Nuclear Information System (INIS)

BenBettaieb, Nasreddine

2008-01-01

Irradiation is one of the effective methods able to change starch structure and its functional properties. In this research the effect of gamma-irradiation (3, 5, 10, 20 and 50kGy) on the rheological, structural, thermal and morphological properties of corn starch was studied. Viscoamylograph test showed that the maximal consistency of the starch paste and its corresponding temperature decrease with increasing irradiation dose. Textural analysis of paste starch using strain-relaxation test showed the dominance of behaviour elastic after irradiation. Discriminant function analysis (DFA) revealed a good discrimination of the irradiation doses among rheological parameters in the strain-relaxation test. FTIR spectra showed that the irradiated starch displayed a significant decrease in the intensity of the O.H stretch (3000.3600 cm 1 ), C.H stretch (2800.3000 cm 1 ), bending mode of water (1600.1800 cm 1 ) and bending mode of glycosidic linkage (900-950 cm-1). The X-ray diffraction spectra show that did not any modification in the sharp and intensity of peaks after irradiation dose. Differential scanning calorimetry (DSC) of corn starch showed decreases in onset (To), final (Tf) and peak (Tp) gelatinisation temperature with increasing irradiation dose. icrophotographs of polarized light microscopy (LPM) showed that up to 50 kGy irradiation did not present any visible physical effect on the corn starch granule. (Author)

Synthesis and Characterization of Starch-based Aqueous Polymer Isocyanate Wood Adhesive

Directory of Open Access Journals (Sweden)

Shu-min Wang

2015-09-01

Full Text Available Modified starch was prepared in this work by acid-thinning and oxidizing corn starch with ammonium persulfate. Also, starch-based aqueous polymer isocyanate (API wood adhesive was prepared. The effect of the added amount of modified starch, styrene butadiene rubber (SBR, polymeric diphenylmethane diisocyanate (P-MDI, and the mass concentration of polyvinyl alcohol (PVOH on the bonding strength of starch-based API adhesives were determined by orthogonal testing. The starch-based API adhesive performance was found to be the best when the addition of modified starch (mass concentration 35% was 45 g, the amount of SBR was 3%, the PVOH mass concentration was 10%, and the amount of P-MDI was 18%. The compression shearing of glulam produced by starch-based API adhesive reached bonding performance indicators of I type adhesive. A scanning electron microscope (SEM was used to analyze the changes in micro-morphology of the starch surface during each stage. Fourier transform infrared spectroscopy (FT-IR was used to study the changes in absorption peaks and functional groups from starch to starch-based API adhesives. The results showed that during starch-based API adhesive synthesis, corn starch surface was differently changed and it gradually reacted with other materials.

Structure and function of starch and resistant starch from corn with different doses of mutant amylose-extender and floury-1 alleles.

Science.gov (United States)

Yao, Ni; Paez, Alix V; White, Pamela J

2009-03-11

Four corn types with different doses of mutant amylose-extender (ae) and floury-1 (fl1) alleles, in the endosperm, including no. 1, aeaeae; no. 2, fl1fl1fl1; no. 3, aeaefl1; and no. 4, fl1fl1ae, were developed for use in making Hispanic food products with high resistant starch (RS) content. The RS percentages in the native starch (NS) of 1-4 were 55.2, 1.1, 5.7, and 1.1%, respectively. All NS were evaluated for pasting properties with a rapid viscoanalyzer (RVA) and for thermal properties with a differential scanning calorimeter (DSC). NS 1 had a low peak viscosity (PV) caused by incomplete gelatinization, whereas NS 3 had the greatest PV and breakdown of all four starch types. On the DSC, NS 2 had the lowest onset temperature and greatest enthalpy. NS 1 and 3 had similar onset and peak temperatures, both higher than those of NS 2 and 4. The gel strength of NS heated with a RVA was evaluated by using a texture analyzer immediately after RVA heating (fresh, RVA-F) and after the gel had been stored at 4 degrees C for 10 days (retrograded, RVA-R). NS 1 gel was watery and had the lowest strength (30 g) among starch gel types. NS 3 gel, although exhibiting syneresis, had greater gel strength than NS 2 and 4. The structures of the NS, the RS isolated from the NS (RS-NS), the RS isolated from RVA-F (RS-RVA-F), and the RS isolated from RVA-R (RS-RVA-R) were evaluated by using size exclusion chromatography. NS 1 had a greater percentage of amylose (AM) (58.3%) than the other NS (20.4-26.8%). The RS from all NS types (RS-NS) had a lower percentage of amylopectin (AP) and a greater percentage of low molecular weight (MW) AM than was present in the original NS materials. The RS-RVA-R from all starches had no AP or high MW AM. The percentages of longer chain lengths (DP 35-60) of NS were greater in 1 and 3 than in 2 and 4, and the percentages of smaller chain lengths (DP 10-20) were greater in 2 and 4 than in 1 and 3. In general, NS 3 seemed to have inherited some pasting

Development and characterisation of composite films made of kefiran and starch.

Science.gov (United States)

Motedayen, Ali Akbar; Khodaiyan, Faramarz; Salehi, Esmail Atai

2013-02-15

In this study, new edible composite films were prepared by blending kefiran with corn starch. Film-forming solutions of different ratios of kefiran to corn starch (100/0, 70/30, 50/50, 30/70) were cast at room temperature. The effects of starch addition on the resulting films' physical, mechanical and water-vapor permeability (WVP) properties were investigated. Increasing starch content from 0% to 50% (v/v) decreased the WVP of films; however, with further starch addition the WVP increased. Also, this increase in starch content increased the tensile strength and extensibility of the composite films. However, these mechanical properties decreased at higher starch contents. Dynamic mechanical thermal analysis (DMTA) curves showed that addition of starch at all levels increased the glass transition temperature of films. The electron scanning micrograph for the composite film was homogeneous, without signs of phase separation between the components. Thus, it was observed that these two film-forming components were compatible, and that an interaction existed between them. Copyright © 2012 Elsevier Ltd. All rights reserved.

The influence of extruded starch molecular mass on the properties of extruded thermoplastic starch

NARCIS (Netherlands)

Soest, van J.J.G.; Benes, K.; Wit, de D.; Vliegenthart, J.F.G.

1996-01-01

The mechanical properties of a low and a high molecular mass thermoplastic starch (TPS) were monitored at water contents in the range of 5-30% (w/w). The granular starches were plasticized by extrusion processing with glycerol and water. The low molecular mass starch was prepared by partial acid

Effect of dispersion parameters on the consolidation of starch-loaded hydroxyapatite slurry

Directory of Open Access Journals (Sweden)

Yasser M.Z. Ahmed

2014-09-01

Full Text Available The influence of some parameters controlling the hydroxyapatite (HA suspension rheology in terms of heat treatment of the HA powder prior to suspension preparation, suspension solid loading and the amount of corn starch addition was thoroughly investigated. The heat treatment of powder at 1100 °C prior to suspension preparation was found to be extremely efficient in preparing suspensions with high solid loading of 59 vol.%. In contrast, the highest solid loading that could be developed from the non-heat treated powder was 14 vol.%. This phenomenon is consequence of the changes in the physical and chemical properties of the powder after the heat treatment step. The amount of native corn starch addition has ranged from 10 to 40 vol.%. The addition of corn starch leads to the high retardation in the suspension viscosity, particularly at low shear rate. On the contrary, at higher shear rate the situation is completely different. The properties of the consolidated green sample (produced from suspensions containing various corn starch amounts in terms of relative density and compressive strength were studied. The results indicated that even though there were no considerable changes in the relative density, the compressive strength was sharply increased with increasing starch amount content until it reached a maximum at 30 vol.% and then decreased thereafter.

Morphological analysis of thermoplastic starch films and montmorillonite (TPS/MMT) using vegetable oils of Brazilian Cerrado as plasticizers;Morfologia de filmes de amido termoplastico e montmorilonita (TPS/MMT) usando oleos vegetais do cerrado como plastificantes

Energy Technology Data Exchange (ETDEWEB)

Schlemmer, Daniela; Sales, Maria Jose A. [Universidade de Brasilia (UnB), DF (Brazil). Lab. de Pesquisa em Polimeros; Angelica, Romulo S. [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Lab. de Raios X; Gomes, Ana Cristina M.M. [Empresa Brasileira de Pesquisa Agropecuaria (EMBRAPA-CENARGEN), Brasilia, DF (Brazil). Lab. de Microscopia Eletronica

2009-07-01

Biopolymers can be used where petrochemical plastics have applications with short life. The excellent degradation of starch and its low cost make it an alternative for obtaining biodegradable plastics. To obtain thermoplastic starch (TPS) is necessary mechanical shake, high temperature and plasticizers. In this work, TPS were produced using three different vegetable oils from Brazilian's cerrado as plasticizers: buriti, macauba or pequi. Materials are also produced with montmorillonite (MMT). All the materials were analyzed by scanning electronic microscopy (SEM) and X-ray diffraction (XRD). The starch micrographs revealed irregular delaminate with a predominance of starch and 'holes' for the oils. In nanocomposites the clusters of clay are dispersed without a defined standard. It was understood that the plasticizers and processing completely changed the structure of starch causing a decrease in their crystallinity degree. Almost all nanocomposites presented exfoliate structure, only one presented intercalated structure. (author)

Protein and starch concentrates of air-classified field pea and zero-tannin faba bean for weaned pigs.

Science.gov (United States)

Gunawardena, C K; Zijlstra, R T; Goonewardene, L A; Beltranena, E

2010-08-01

Air-classified pulse (non-oilseed legume) protein and starch may replace specialty protein and starch feedstuffs in diets for weaned pigs. In Exp. 1, three specialty protein sources (5% soy protein concentrate, 5% corn gluten meal, and 5% menhaden meal in the control diet) were replaced with 16% zero-tannin hulled or dehulled faba bean, or 17.5% field pea protein concentrate. In total, 192 group-housed pigs (2 gilts and 2 barrows per pen; BW = 7.5 +/- 1.4 kg) were fed wheat-based diets (3.60 Mcal/kg of DE and 3.3 g of standardized ileal digestible Lys/Mcal DE) over 28 d for 12 pen observations per each of 4 diets. Overall, protein source did not affect ADFI, ADG, or G:F. Apparent total tract digestibility (ATTD) of DM, GE, and P was greater (P bean and field pea protein concentrate diets than the diet with 3 specialty protein sources. In Exp. 2, faba bean and field pea starch concentrates were compared with corn, wheat, tapioca, and potato starch as dietary energy sources. In total, 36 individually housed barrows (BW = 8.0 +/- 1.5 kg) were fed 1 of 6 diets for 15 d. Feces and urine were collected from d 8 to 14, and jugular blood was sampled after overnight fast and refeeding on d 15. Starch source did not affect N retention as a percentage of N intake. For d 0 to 14, ADFI of pigs fed field pea starch was greater (P bean starch. Pigs fed tapioca, field pea, wheat, or corn starch grew faster (P bean or potato starch. For d 0 to 14, pigs fed corn or wheat starch had a 0.1 greater (P bean, field pea, or potato starch. The ATTD of DM, GE, CP, and starch and the DE value of potato starch were much less (P bean, wheat, and potato starch, respectively. However, postprandial plasma insulin tended to be 844 and 577 pmol/L greater (P bean and corn starch, respectively, than for pigs fed potato starch. The high insulin response of pigs fed faba starch could not be explained. In conclusion, air-classified pulse protein concentrates can replace specialty protein feedstuffs in

Effects of lipids on enzymatic hydrolysis and physical properties of starch.

Science.gov (United States)

Ai, Yongfeng; Hasjim, Jovin; Jane, Jay-lin

2013-01-30

This study aimed to understand effects of lipids, including corn oil (CO), soy lecithin (SL), palmitic acid (PA), stearic acid (SA), oleic acid (OA), and linoleic acid (LA), on the enzymatic hydrolysis and physical properties of normal corn (NCS), tapioca (TPS), waxy corn (WCS), and high-amylose corn (HA7) starch, and to elucidate mechanisms of interactions between the starches and lipids. After cooking with the lipids (10%, w/w, dsb), NCS, TPS, and HA7 showed significant decreases in enzymatic hydrolysis, and their DSC thermograms displayed amylose-lipid-complex dissociation peaks except with the CO. (13)C NMR spectra of amylodextrin with CO showed downfield changes in the chemical shifts of carbons 1 and 4 of the anhydroglucose unit, indicating helical complex formation. Generally, free fatty acids (FFAs) reduced, but SL increased the peak viscosities of starches. FFAs and SL decreased, but CO increased the gel strength of NCS. These lipids displayed little impacts on the enzymatic hydrolysis and physical properties of WCS because it lacked amylose. Copyright © 2012 Elsevier Ltd. All rights reserved.

Physicochemical and functional properties of starches of two quality ...

African Journals Online (AJOL)

SARAH

2013-06-30

Jun 30, 2013 ... water expelled from white QPM starch was 40.39% at -15°C and 37.05% at 4°C after the first week of storage ... include starch, high-fructose corn syrup and livestock ... associations of 40–70 glucose units whereas.

ENZYME RESISTANCE OF GENETICALLY MODIFIED STARCH POTATOES

Directory of Open Access Journals (Sweden)

A. Sh. Mannapova

2015-01-01

Full Text Available Here in this article the justification of expediency of enzyme resistant starch use in therapeutic food products is presented . Enzyme resistant starch is capable to resist to enzymatic hydrolysis in a small intestine of a person, has a low glycemic index, leads to decrease of postprandial concentration of glucose, cholesterol, triglycerides in blood and insulin reaction, to improvement of sensitivity of all organism to insulin, to increase in sense of fulness and to reduction of adjournment of fats. Resistant starch makes bifidogenшс impact on microflora of a intestine of the person, leads to increase of a quantity of lactobacillus and bifidobacterium and to increased production of butyric acid in a large intestine. In this regard the enzyme resistant starch is an important component in food for prevention and curing of human diseases such as diabetes, obesity, colitis, a cancer of large and direct intestine. One method is specified by authors for imitation of starch digestion in a human body. This method is based on the definition of an enzyme resistance of starch in vitro by its hydrolysis to glucose with application of a glucoamylase and digestive enzyme preparation Pancreatin. This method is used in researches of an enzyme resistance of starch, of genetically modified potato, high amylose corn starch Hi-Maize 1043 and HYLON VII (National Starch Food Innovation, USA, amylopectin and amylose. It is shown that the enzyme resistance of the starch emitted from genetically modified potatoes conforms to the enzyme resistance of the high amylose corn starch “Hi-Maize 1043 and HYLON VII starch”, (National Starch Food Innovation, the USA relating to the II type of enzyme resistant starch. It is established that amylopectin doesn't have the enzyme resistant properties. The results of researches are presented. They allow us to make the following conclusion: amylose in comparison with amylopectin possesses higher enzyme resistance and gives to

Production and quality evaluation of extruded snack from blends of bambara groundnut flour, cassava starch, and corn bran flour

OpenAIRE

Ogunmuyiwa, O. H.; Adebowale, A. A.; Sobukola, O. P.; Onabanjo, O. O.; Obadina, A. O.; Adegunwa, M. O.; Kajihausa, O. E.; Sanni, L. O.; Tomlins, Keith

2017-01-01

Protein dense, fiber-rich extruded snacks were produced from blend of bambara groundnut flour, cassava starch, and corn bran flour using a single screw cooking extruder. The snacks were analyzed for their physical properties and proximate composition using standard laboratory procedures. The expansion ratio, specific volume, breaking force, and breaking strength index (BSI) of the snacks ranged from 0.85 to 1.22, 0.75 to 1.30 g/cm3, 3.95 to 36.45 N, and 0.99 to 9.11 N/mm, respectively. The br...

Xylanase and Protease Increase Solubilization of Non-Starch Polysaccharides and Nutrient Release of Corn- and Wheat Distillers Dried Grains with Solubles

DEFF Research Database (Denmark)

Pedersen, Mads Brøgger; Dalsgaard, Søren; Arent, Susan

2015-01-01

The use of distiller dried grains with solubles (DDGS) as alternative to conventional animal feed for non-ruminants is challenged by the high content of non-starch polysaccharides and varying protein quality. In this study the enzymatic degradation of corn- and wheat DDGS was evaluated, in vitro...... of this xylanase. The current in vitro results indicate a high potential of xylanase in combination with protease to efficiently degrade DDGS and promote nutrient release in diets for non-ruminant animals....

Granules morphology and rheological behavior of green banana (Musa cavendishii and corn (Zea mays starch gels Morfologia dos grânulos e comportamento reológico dos géis de amido de banana verde (Musa cavendishii e milho (Zea mays

Directory of Open Access Journals (Sweden)

Dayane Rosalyn Izidoro

2007-10-01

Full Text Available In this work, it was used starch obtained from green banana (Musa cavendishii and commercial corn (Zea mays starch in order to compare the granule morphology and the rheological behavior of these gel-starches. Images of starch granules morphology were obtained from scanning electron microscope (SEM. The banana starch granules presented an oval and ellipsoidal shape with irregular diameters. Neverthless, the granules of corn starch showed a poliedric shape, with different sizes. The rheological behavior of gel starch solutions showed a non-newtonian character with a pseudoplastic behavior. Herschel-Bulkley model gave a good description on the rheological behavior of the gel starch. Banana gel-starch solutions showed higher values of shear stress and apparent viscosity when compared with corn gel-starch solutions. A progressive decrease in shear stress and viscosity occurred with the addition of sodium chloride and sucrose.No presente trabalho foi utilizado amido obtido de banana verde (Musa cavendishii e amido de milho (Zea mays comercial, com o objetivo de comparar a morfologia dos grânulos e o comportamento reológico dos géis. As imagens da morfologia dos grânulos foram obtidas por microscopia eletrônica de varredura. Os grânulos de amido da banana apresentaram forma oval e elipsoidal com diâmetros irregulares, todavia, os grânulos do amido de milho mostraram forma poliédrica e diferentes tamanhos. As análises reológicas dos géis das soluções de amido mostraram caráter não-newtoniano, pseudoplástico. O modelo de Herschel-Bulkley foi o que melhor representou comportamento reológico dos géis. O gel de amido de banana verde obteve maiores valores de tensão de cisalhamento e viscosidade aparente quando comparada ao gel de amido de milho. Ocorreu um decréscimo progressivo na tensão de cisalhamento e na viscosidade com a adição de cloreto de sódio e sacarose aos géis.

Simultaneous saccharification and cofermentation of lignocellulosic residues from commercial furfural production and corn kernels using different nutrient media

Directory of Open Access Journals (Sweden)

Cristhian Carrasco

2011-07-01

Full Text Available Abstract Background As the supply of starch grain and sugar cane, currently the main feedstocks for bioethanol production, become limited, lignocelluloses will be sought as alternative materials for bioethanol production. Production of cellulosic ethanol is still cost-inefficient because of the low final ethanol concentration and the addition of nutrients. We report the use of simultaneous saccharification and cofermentation (SSCF of lignocellulosic residues from commercial furfural production (furfural residue, FR and corn kernels to compare different nutritional media. The final ethanol concentration, yield, number of live yeast cells, and yeast-cell death ratio were investigated to evaluate the effectiveness of integrating cellulosic and starch ethanol. Results Both the ethanol yield and number of live yeast cells increased with increasing corn-kernel concentration, whereas the yeast-cell death ratio decreased in SSCF of FR and corn kernels. An ethanol concentration of 73.1 g/L at 120 h, which corresponded to a 101.1% ethanol yield based on FR cellulose and corn starch, was obtained in SSCF of 7.5% FR and 14.5% corn kernels with mineral-salt medium. SSCF could simultaneously convert cellulose into ethanol from both corn kernels and FR, and SSCF ethanol yield was similar between the organic and mineral-salt media. Conclusions Starch ethanol promotes cellulosic ethanol by providing important nutrients for fermentative organisms, and in turn cellulosic ethanol promotes starch ethanol by providing cellulosic enzymes that convert the cellulosic polysaccharides in starch materials into additional ethanol. It is feasible to produce ethanol in SSCF of FR and corn kernels with mineral-salt medium. It would be cost-efficient to produce ethanol in SSCF of high concentrations of water-insoluble solids of lignocellulosic materials and corn kernels. Compared with prehydrolysis and fed-batch strategy using lignocellulosic materials, addition of starch

Estudo comparativo de amidos termoplásticos derivados do milho com diferentes teores de amilose Comparative studies of corn thermoplastic starches with different amylose content

Directory of Open Access Journals (Sweden)

Elisângela Corradini

2005-11-01

Full Text Available Amidos de milho contendo aproximadamente 72 e 100 % de amilopectina foram convertidos em amidos termoplásticos por processamento em um misturador intensivo a 160 ºC, usando glicerol como plastificante. Os amidos termoplásticos foram condicionados em ambiente de 53 ± 2% u.r. e caracterizados por medidas de absorção de água, difração de raios X, ensaios mecânicos de tração e por análises dinâmico mecânicas (DMA. O amido com menor teor de amilopectina apresentou maior viscosidade durante o processamento, que foi atribuída à estrutura da amilose. Os amidos termoplásticos TPS1 (72% de amilopectina e TPS2 (100% de amilopectina não mostraram diferenças apreciáveis nas propriedades de absorção de água. Após duas semanas de armazenamento, o TPS1 apresentou estrutura semicristalina, enquanto o TPS2 apresentou estrutura totalmente amorfa. Após seis semanas ocorreu um aumento da cristalinidade do TPS1 e ocorreu a formação de estruturas cristalinas no TPS2. As propriedades mecânicas e dinâmico-mecânicas foram afetadas pela cristalinidade do amido que é função da razão amilose/amilopectina.Corn starches with approximately 72% and 100 % of amylopectin were processed in an intensive mixer connected to a torque rheometer in the presence of glycerol (plasticizer at 160ºC. The thermoplastic starches were conditioned at 53 ± 2% of relative humidity for two weeks and characterized by X-ray diffraction, tensile test and dynamical mechanical analysis (DMA. The starch with lower amylopectin content presented higher viscosity during the processing which was attributed to linear amylose chains. The thermoplastic starches TPS1 (72% of amylopectin and TPS2 (100% of amylopectin did not display significant differences in water absorption. After two weeks of aging, TPS1 exhibited semicrystalline structure, whereas TPS2 presented a amorphous structure. After six weeks, the crystallinity of TPS1 increased and some crystalline behavior could

Fact sheet: Ethanol from corn

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-05-31

This fact sheet is intended to provide an overview of the advantages of ethanol from corn, emphasizing ethanol`s contribution to environmental protection and sustainable agriculture. Ethanol, an alternative fuel used as an octane enhancer is produced through the conversion of starch to sugars by enzymes, and fermentation of these sugars to ethanol by yeast. The production process may involve wet milling or dry milling. Both these processes produce valuable by-products, in addition to ethanol and carbon dioxide. Ethanol contains about 32,000 BTU per litre. It is commonly believed that using state-of-the-art corn farming and corn processing processes, the amount of energy contained in ethanol and its by-products would be more than twice the energy required to grow and process corn into ethanol. Ethanol represents the third largest market for Ontario corn, after direct use as animal feed and wet milling for starch, corn sweetener and corn oil. The environmental consequences of using ethanol are very significant. It is estimated that a 10 per cent ethanol blend in gasoline would result in a 25 to 30 per cent decrease in carbon monoxide emissions, a 6 to 10 per cent decrease in net carbon dioxide, a slight increase in nitrous oxide emissions which, however, would still result in an overall decrease in ozone formation, since the significant reduction in carbon monoxide emissions would compensate for any slight increase in nitrous oxide. Volatile organic compounds emission would also decrease by about 7 per cent with a 10 per cent ethanol blend. High level blends could reduce VOCs production by as much as 30 per cent. 7 refs.

Gluten-free dough-making of specialty breads: Significance of blended starches, flours and additives on dough behaviour.

Science.gov (United States)

Collar, Concha; Conte, Paola; Fadda, Costantino; Piga, Antonio

2015-10-01

The capability of different gluten-free (GF) basic formulations made of flour (rice, amaranth and chickpea) and starch (corn and cassava) blends, to make machinable and viscoelastic GF-doughs in absence/presence of single hydrocolloids (guar gum, locust bean and psyllium fibre), proteins (milk and egg white) and surfactants (neutral, anionic and vegetable oil) have been investigated. Macroscopic (high deformation) and macromolecular (small deformation) mechanical, viscometric (gelatinization, pasting, gelling) and thermal (gelatinization, melting, retrogradation) approaches were performed on the different matrices in order to (a) identify similarities and differences in GF-doughs in terms of a small number of rheological and thermal analytical parameters according to the formulations and (b) to assess single and interactive effects of basic ingredients and additives on GF-dough performance to achieve GF-flat breads. Larger values for the static and dynamic mechanical characteristics and higher viscometric profiles during both cooking and cooling corresponded to doughs formulated with guar gum and Psyllium fibre added to rice flour/starch and rice flour/corn starch/chickpea flour, while surfactant- and protein-formulated GF-doughs added to rice flour/starch/amaranth flour based GF-doughs exhibited intermediate and lower values for the mechanical parameters and poorer viscometric profiles. In addition, additive-free formulations exhibited higher values for the temperature of both gelatinization and retrogradation and lower enthalpies for the thermal transitions. Single addition of 10% of either chickpea flour or amaranth flour to rice flour/starch blends provided a large GF-dough hardening effect in presence of corn starch and an intermediate effect in presence of cassava starch (chickpea), and an intermediate reinforcement of GF-dough regardless the source of starch (amaranth). At macromolecular level, both chickpea and amaranth flours, singly added, determined

Fuel ethanol production from granular corn starch using Saccharomyces cerevisiae in a long term repeated SSF process with full stillage recycling.

Science.gov (United States)

Białas, Wojciech; Szymanowska, Daria; Grajek, Włodzimierz

2010-05-01

A major problem with fermentative ethanol production is the formation of large amounts of numerous organic pollutants. In an industrial distillery, stillage, fermenter and condenser cooling water are the main sources of wastewater. However, the selection of a proper technology makes it possible to almost completely avoid emissions of such kind of wastewater to the environment. This study examines the effect of stillage recirculation on fuel ethanol production. It is based on the use of Saccharomyces cerevisiae and a granular starch hydrolyzing enzyme in a simultaneous saccharification and fermentation process using a native starch obtained from corn flour. It was shown that the yield of the ethanol production was not influenced by the recycled stillage, a mean yield being 83.38% of the theoretical value. No significant trend for change in the ethanol concentration or in the residual starch was observed during any particular run, even after the 75% of fresh water was replaced with stillage. Thus, by applying this new clean technology it is possible to significantly reduce the rate of water consumption and in this way the production of by-products such as stillage. Copyright 2009 Elsevier Ltd. All rights reserved.

Development of starch-based materials

NARCIS (Netherlands)

Habeych Narvaez, E.A.

2009-01-01

Starch-based materials show potential as fully degradable plastics. However, the current
applicability of these materials is limited due to their poor moisture tolerance and
mechanical properties. Starch is therefore frequently blended with other polymers to make
the material more

Biodegradability and mechanical properties of reinforced starch nanocomposites using cellulose nanofibers.

Science.gov (United States)

Babaee, Mehran; Jonoobi, Mehdi; Hamzeh, Yahya; Ashori, Alireza

2015-11-05

In this study the effects of chemical modification of cellulose nanofibers (CNFs) on the biodegradability and mechanical properties of reinforced thermoplastic starch (TPS) nanocomposites was evaluated. The CNFs were modified using acetic anhydride and the nanocomposites were fabricated by solution casting from corn starch with glycerol/water as the plasticizer and 10 wt% of either CNFs or acetylated CNFs (ACNFs). The morphology, water absorption (WA), water vapor permeability rate (WVP), tensile, dynamic mechanical analysis (DMA), and fungal degradation properties of the obtained nanocomposites were investigated. The results demonstrated that the addition of CNFs and ACNFs significantly enhanced the mechanical properties of the nanocomposites and reduced the WVP and WA of the TPS. The effects were more pronounced for the CNFs than the ACNFs. The DMA showed that the storage modulus was improved, especially for the CNFs/TPS nanocomposite. Compared with the neat TPS, the addition of nanofibers improved the degradation rate of the nanocomposite and particularly ACNFs reduced degradation rate of the nanocomposite toward fungal degradation. Copyright © 2015 Elsevier Ltd. All rights reserved.

GABA content and Antioxidant activity of Thai waxy corn seeds germinated by hypoxia method

Directory of Open Access Journals (Sweden)

Pisamai Polthum

2014-06-01

Full Text Available Germinated seeds have a greater amount of the naturally-occurring -aminobutyric acid (GABA which has many health benefits. Further, colored seeds have higher antioxidant activity. Thai waxy corn is widely consumed after cooking, due to its palatable glutinous texture. However, it is not commonly germinated before use. In this study, two varieties of Thai waxy corn, KKU-KND (purple seed and KKU-SLE (white seed, were germinated and converted to corn flour with the aim of investigating the effect of germination on GABA content and antioxidant activity. Further, the microstructure of starch granules was also examined. KKU-KND and KKU-SLE were grown and harvested in 2012. The seeds were soaked in distilled water for 6 hrs to attain a moisture content of 31-32%wb and then germinated by employing two methods, i in an open plastic box, and ii in a closed plastic box with a headspace of 3 cm for devoid oxygen (hypoxia method; the germination period varied between 12-48 hrs at 35±2°C in both cases. The germinated samples were then dried at 50°C to a moisture content of 10±2%wb. The results showed that non-germinated KKU-KND and KKU-SLE contained 2.68±0.77 and 1.58±0.05 mgGABA/ 100gdb, respectively, whereas the samples germinated by the hypoxia method contained significantly higher GABA which increased with germination time (p<0.05. The highest GABA contents found in KKU-KND and KKU-SLE were 37.20±3.27 and 54.47±2.08 mg/100gdb, respectively after 48 hrs of germination under the hypoxia method. In addition, the germinated KKU-KND gave ABTS and DPPH values of 388.32±0.53 and 140.29±0.57 mgTrolox/100gdb, whereas the germinated KKU-SLE gave ABTS and DPPH values of 183.69±1.75 and 38.43±1.64 mgTrolox/100gdb, respectively. The pictures of starch granules obtained by means of SEM displayed differences in the shape and size of the non-germinated and germinated granules in both verities. In conclusion, the hypoxia method is able to induce higher GABA

Novel polymer blends with thermoplastic starch

Science.gov (United States)

Taghizadeh, Ata

A new class of polymers known as "bioplastics" has emerged and is expanding rapidly. This class consists of polymers that are either bio-based or biodegradable, or both. Among these, polysaccharides, namely starch, are of great interest for several reasons. By gelatinizing starch via plasticizers, it can be processed in the same way as thermoplastic polymers with conventional processing equipment. Hence, these bio-based and biodegradable plastics, with their low source and refinery costs, as well as relatively easy processability, have made them ideal candidates for incorporation into various current plastic products. Four different plasticizers have been chosen here for gelatinization of thermoplastic starch (TPS): glycerol, sorbitol, diglycerol and polyglycerol, with the latter two being used for the first time in such a process. Two methodological categories are used. The first involves a calorimetric method (Differential Scanning Calorimetry) as well as optical microscopy; these are "static" methods where no shear is applied A wide range of starch/water/plasticizer compositions were prepared to explore the gelatinization regime for each plasticizer. The onset and conclusion gelatinization temperatures for sorbitol and glycerol were found to be in the same vicinity, while diglycerol and polyglycerol showed significantly higher transition temperatures. The higher molecular weight and viscosity of polyglycerol allow this transition to occur at an even higher temperature than with diglycerol. This is due to the increase in molecular weight and viscosity of the two new plasticizers, as well as their significant decrease in water solubility. It is demonstrated that the water/plasticizer ratio has a pronounced effect on gelatinization temperatures. When plasticizer content was held constant and water content was increased, it was found that the gelatinization temperature decreased for all the plasticizers. Meanwhile, when the water content was held constant and the

Oxidação dos amidos de mandioca e de milho comum fermentados: desenvolvimento da propriedade de expansão Oxidation of fermented cassava and corn starches: development of the expansion property

Directory of Open Access Journals (Sweden)

Alvaro Renato Guerra Dias

2007-12-01

Full Text Available Amidos de mandioca e de milho comum foram fermentados em laboratório a 20 °C, sendo uma fração seca ao sol e outra oxidada com peróxido de hidrogênio e secada artificialmente, visando o desenvolvimento da propriedade de expansão. Estudou-se a fermentação em 0, 10, 30 e 50 dias, sendo a propriedade de expansão no forneamento avaliada pelo teste do biscoito e o comportamento viscoamilográfico pelo RVA. Verificou-se que a fermentação promove modificação que auxilia na oxidação dos amidos de mandioca e de milho elevando a acidez titulável do produto. O amido de mandioca fermentado oxidado com exposição solar ou com peróxido de hidrogênio pode desenvolver a propriedade de expansão, já o amido de milho comum nessas condições não tem essa capacidade. Os melhores resultados para a propriedade de expansão foram no amido de mandioca oxidado com peróxido de hidrogênio aos 50 dias de fermentação.Cassava and corn starches were fermented in the laboratory at 20 °C, and a fraction was in the sun while another fraction was oxidized with hydrogen peroxide and dried artificially to develop the expansion property. Fermentation in 0, 10, 30 and 50 days was checked and the expansion property was evaluated by the baking test and viscoamilograph behavior (RVA. Fermentation was found to cause changes that help the oxidation of cassava and corn starches, increasing the product's titrable acidity. The fermented cassava starch, oxidized by exposure to sunlight or hydrogen peroxide, may develop the expansion property, but the corn starch did not display that ability under these conditions. The best results for the expansion property were obtained with cassava starch oxidized with hydrogen peroxide after 50 days of fermentation.

Caracterização físico-química, reológica, morfológica e térmica dos amidos de milho normal, ceroso e com alto teor de amilose Physicochemical, rheological, morphological, and thermal characterization of normal, waxy, and high amylose corn starches

Directory of Open Access Journals (Sweden)

Fernanda Hart Weber

2009-12-01

Full Text Available O objetivo do presente estudo foi avaliar os amidos de milho normal, ceroso e com alto teor de amilose, fabricados pela National Starch, por meio da determinação das suas características físico-químicas, morfológicas, térmicas e reológicas. O amido de milho com alto teor de amilose (AM apresentou teor de amilose igual a 71%, sendo que os valores obtidos para o amido de milho normal (M e o amido de milho ceroso (AP foram de 27,8 e 1,8%, respectivamente. Traços de proteína e lipídios foram encontrados nas amostras. O amido de milho ceroso apresentou maior viscosidade máxima e uma menor tendência à retrogradação, se comparado ao amido de milho normal. O amido AP apresentou menor entalpia de gelatinização, como pode ser observado nas análises de calorimetria exploratória diferencial (DSC, na qual a temperatura de gelatinização foi de 75 °C e o ΔH de 3,34 J.g-1, e também na análise de RVA (Rapid Visco Analyser, em que a temperatura de pasta foi de 71 °C. Apresentando, dessa forma, valores inferiores aos verificados para os outros amidos. O valor do ΔH de retrogradação do amido AP, mostrou-se 25,8% inferior ao ΔH do amido M. O amido AM apresentou o valor de 26,38 J.g-1, demonstrando o maior envolvimento da molécula de amilose no processo de retrogradação. Isso também foi evidenciado pela medida da força dos géis: o gel de AM apresentou força 99,18% superior, retrogradando mais que os outros amidos. As análises de difração de raio X mostraram que os amidos de milho normal e ceroso apresentaram um padrão de difração do tipo A e o amido de milho com alto teor de amilose apresentou padrão do tipo B.The objective of this work was to evaluate normal, waxy, and high amylose corn starches from National Starch, through the determination of the physicochemical, morphological, thermal, and rheological properties. The high amylose corn starch (AM presented amylose content of 71%, and the value of this component for the

Preparation and properties of novel melt-blended halloysite nanotubes/wheat starch nanocomposites.

Science.gov (United States)

Schmitt, H; Prashantha, K; Soulestin, J; Lacrampe, M F; Krawczak, P

2012-07-01

Novel bionanocomposites based on halloysite nanotubes as nanofillers and plasticized starch as polymeric matrix were successfully prepared by melt-extrusion for the first time. Both modified and non modified halloysites were added at different weight contents. The structural, morphological, thermal and mechanical properties of plasticized starch/halloysites nanocomposites were investigated. Melt-compounding appears to be a suitable process to uniformly disperse nanotubes in the plasticized starch matrix. Interactions between plasticized starch and halloysites in the nanocomposites and microstructure modifications were monitored using Fourier transfer infrared spectroscopy, X-ray diffraction and dynamic mechanical analysis. Addition of halloysite nanotubes slightly enhances the thermal stability of starch (onset temperature of degradation delayed to higher temperatures). The tensile mechanical properties of starch are also significantly improved (up to +144% for Young's modulus and up to +29% for strength) upon addition of both modified and unmodified halloysites, interestingly without loss of ductility. Modified halloysites lead to significantly higher Young's modulus than unmodified halloysites. Copyright © 2012 Elsevier Ltd. All rights reserved.

An enzyme complex increases in vitro dry matter digestibility of corn and wheat in pigs.

Science.gov (United States)

Park, Kyu Ree; Park, Chan Sol; Kim, Beob Gyun

2016-01-01

Two experiments were conducted to determine the effects of enzyme complex on in vitro dry matter (DM) digestibility for feed ingredients. The objective of experiment 1 was to screen feed ingredients that can be effective substrates for an enzyme complex, mainly consisted of β-pentosanase, β-glucanase and α-amylase, using in vitro digestibility methods. In experiment 1, the test ingredients were three grain sources (barley, corn and wheat) and six protein supplements (canola meal, copra expellers, cottonseed meal, distillers dried grains with solubles, palm kernel expellers and soybean meal). In vitro ileal and total tract digestibility (IVID and IVTTD, respectively) of DM for test ingredients were determined. In vitro digestibility methods consisted of two- or three-step procedure simulating in vivo digestion in the pig gastrointestinal tracts with or without enzyme complex. As the enzyme complex added, the IVID of DM for corn and wheat increased (p digestibility, corn grains were selected to determine the in vitro digestibility of the fractions (starch, germ, hull and gluten) that maximally respond to the enzyme complex in experiment 2. The IVID of DM for corn starch, germ and hull increased (p digestibility of corn and wheat, and the digestibility increments of corn are mainly attributed to the increased digestibility of corn starch.

Fabrication and characterization of size-controlled starch-based nanoparticles as hydrophobic drug carriers.

Science.gov (United States)

Han, Fei; Gao, Chunmei; Liu, Mingzhu

2013-10-01

Acetylated corn starch was successfully synthesized and optimized by the reaction of native corn starch with acetic anhydride and acetic acid in the presence of sulfuric acid as a catalyst. The optimal degree of substitution of 2.85 was obtained. Starch-based nanoparticles were fabricated by a simple and novel nanoprecipitation procedure, by the dropwise addition of water to acetone solution of acetylated starch under stirring. Fourier transform infrared spectrometry showed that acetylated starch had some new bands at 1750, 1375 and 1240 cm(-1) while acetylated starch nanoparticles presented the identical peaks as the drug-loaded acetylated starch nanoparticles and the acetylated starch. Wide angle X-ray diffraction indicated that A-type pattern of native starch was completely transformed into the V-type pattern of Acetylated starch and starch-based nanoparticles show the similar type pattern with the acetylated starch. The scanning electron microscopy showed that the different sizes of pores formed on the acetylated starch granules were utterly converted into the uniform-sized spherical nanoparticles after the nanoprecipitation. The encapsulation efficiency and diameter of nanoparticle can be adjusted by the degree of substitution, the volume ratio of nonsolvent to solvent and the weight ratio of acetylated starch to drug. It was also depicted that the release behaviors of drug-loaded nanoparticles depend on the size of nanoparticles and the degree of substitution of the acetylated starch. Release studies prove that the starch-based nanoparticles with uniform size can be used for the encapsulation of hydrophobic drug and attained the sustained and controllable drug release carriers.

Characterization of blend hydrogels based on plasticized starch/cellulose acetate/carboxymethyl cellulose synthesized by electron beam irradiation

Energy Technology Data Exchange (ETDEWEB)

Senna, Magdy M., E-mail: magdysenna@hotmail.com [Radiation Chemistry Department, National Center for Radiation Research and Technology, Atomic Energy Authority, Cairo (Egypt); Mostafa, Abo El-Khair B. [Chemistry Department, College for Girls, Ain Shams University, Cairo (Egypt); Mahdy, Sanna R.; El-Naggar, Abdel Wahab M. [Radiation Chemistry Department, National Center for Radiation Research and Technology, Atomic Energy Authority, Cairo (Egypt)

2016-11-01

Highlights: • Semi-interpenetrating (IPN) blend hydrogels were synthesized by EB irradiation. • The hydrogels were based on starch/cellulose acetate/carboxymethyl cellulose blends. • The gelation, swelling, thermal and mechanical properties of hydrogels were studied. • The thermal stability was studied by determining kinetic energy by different methods. - Abstract: Blend hydrogels based on aqueous solutions of plasticized starch and different ratios of cellulose acetate (CA) and carboxymethyl cellulose (CMC) were prepared by electron beam irradiation (EB). The blends before and after EB irradiation were characterized by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The physico-chemical properties of blend hydrogels prepared by electron beam irradiation were improved compared to unirradiated blends.

Characterization of blend hydrogels based on plasticized starch/cellulose acetate/carboxymethyl cellulose synthesized by electron beam irradiation

International Nuclear Information System (INIS)

Senna, Magdy M.; Mostafa, Abo El-Khair B.; Mahdy, Sanna R.; El-Naggar, Abdel Wahab M.

2016-01-01

Highlights: • Semi-interpenetrating (IPN) blend hydrogels were synthesized by EB irradiation. • The hydrogels were based on starch/cellulose acetate/carboxymethyl cellulose blends. • The gelation, swelling, thermal and mechanical properties of hydrogels were studied. • The thermal stability was studied by determining kinetic energy by different methods. - Abstract: Blend hydrogels based on aqueous solutions of plasticized starch and different ratios of cellulose acetate (CA) and carboxymethyl cellulose (CMC) were prepared by electron beam irradiation (EB). The blends before and after EB irradiation were characterized by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The physico-chemical properties of blend hydrogels prepared by electron beam irradiation were improved compared to unirradiated blends.

Thermoplastic starch materials prepared from rice starch; Preparacao e caracterizacao de materiais termoplasticos preparados a partir de amido de arroz

Energy Technology Data Exchange (ETDEWEB)

Pontes, Barbara R.B.; Curvelo, Antonio A.S., E-mail: barbarapont@gmail.co [Universidade de Sao Paulo (IQSC/USP), Sao Carlos, SP (Brazil). Inst. de Quimica

2009-07-01

Rice starch is a source still little studied for the preparation of thermoplastic materials. However, its characteristics, such as the presence of proteins, fats and fibers may turn into thermoplastics with a better performance. The present study intends the evaluation of the viability of making starch thermoplastic from rice starch and glycerol as plasticizer. The results of X-ray diffraction and scanning electronic microscopy demonstrate the thermoplastic acquisition. The increase of plasticizer content brings on more hydrophilic thermoplastics with less resistance to tension and elongation at break. (author)

Tailoring barrier properties of thermoplastic corn starch-based films (TPCS) by means of a multilayer design.

Science.gov (United States)

Fabra, María José; López-Rubio, Amparo; Cabedo, Luis; Lagaron, Jose M

2016-12-01

This work compares the effect of adding different biopolyester electrospun coatings made of polycaprolactone (PCL), polylactic acid (PLA) and polyhydroxybutyrate (PHB) on oxygen and water vapour barrier properties of a thermoplastic corn starch (TPCS) film. The morphology of the developed multilayer structures was also examined by Scanning Electron Microscopy (SEM). Results showed a positive linear relationship between the amount of the electrospun coatings deposited onto both sides of the TPCS film and the thickness of the coating. Interestingly, the addition of electrospun biopolyester coatings led to an exponential oxygen and water vapour permeability drop as the amount of the electrospun coating increased. This study demonstrated the versatility of the technology here proposed to tailor the barrier properties of food packaging materials according to the final intended use. Copyright © 2016 Elsevier Inc. All rights reserved.

Modification of Foamed Articles Based on Cassava Starch

International Nuclear Information System (INIS)

Ponce, P.

2006-01-01

This work reports the influence of radiation, plasticizers and poly vinyl alcohol (PVA) on the barrier properties [water vapour permeability (WVP)) and mechanical properties (tensile strength and elongation; compression resistance and flexibility) of foamed articles based on cassava starch. The starch foam was obtained by thermopressing process. Poly ethylene glycol (PEG, 300) was selected as plasticizer and water was necessary for the preparation of the foams. The foamed articles based on cassava starch were irradiated at low doses of 2 and 5 kGy, commonly used in food irradiation. The mechanical properties of starch foams are influenced by the plasticizer concentration and by irradiation dose. An increase in PEG content showed a considerable increase in elongation percentage and a decrease in the tensile strength of the foams; also increase the permeability of the foams in water. After irradiation, the barrier properties and mechanical properties of the foams were improved due to chemical reactions among polymer molecules. Irradiated starch cassava foams with poly vinyl alcohol (PVA) have good flexibility and low water permeability. WVP can be reduced by low doses of gamma radiation

Microbiological and technological quality of corn and faba bean as affected by varying levels of gamma irradiation

International Nuclear Information System (INIS)

Youssef, B.M.; Swailam, H.M.H.; Elsamahy, S.K.

1995-01-01

Samples of corn and faba bean grains subjected to different doses of gamma radiation. The microbiological, physical and physicochemical properties of irradiated grains were assessed as compared with control. corn starch was extracted from irradiated corn grains and its quality evaluated. The results showed that increasing irradiation dose caused a gradual reduction in total bacterial counts, counts of spore forming bacteria, coliform group, mold and yeast in corn grains. The same trend applies to the effect of storage period for irradiated samples. 7.5 KGy was found to eliminate all microorganisms. Increasing irradiation dose from 1.0 to 10.0 KGy caused an increase in soundness number and water absorption of corn grains, acidity, reducing power and solubility of isolated starch while the swelling power and water binding capacity of starch were reduced. The rate of change during storage period was lower in the irradiated samples than in the untreated ones. 7 figs., 3 tabs

Evaluation of Starch Biodegradable Plastics Derived from Cassava ...

African Journals Online (AJOL)

BSN

bioplastics produced from cassava does not depend on the level of amylose and amylopectin in the starch per se ... cassava starch is a pure, natural biopolymer that is suitable for ... enzymatic action of microorganisms when disposed, is thus ...

Characterization of blend hydrogels based on plasticized starch/cellulose acetate/carboxymethyl cellulose synthesized by electron beam irradiation

Science.gov (United States)

Senna, Magdy M.; Mostafa, Abo El-Khair B.; Mahdy, Sanna R.; El-Naggar, Abdel Wahab M.

2016-11-01

Blend hydrogels based on aqueous solutions of plasticized starch and different ratios of cellulose acetate (CA) and carboxymethyl cellulose (CMC) were prepared by electron beam irradiation (EB). The blends before and after EB irradiation were characterized by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The physico-chemical properties of blend hydrogels prepared by electron beam irradiation were improved compared to unirradiated blends.

Mechanical properties of a high amylose content corn starch based film, gelatinized at low temperature Propriedades mecânicas de filme a base de amido de milho de alto teor de amilose gelatinizado em baixa temperatura

Directory of Open Access Journals (Sweden)

Maria Alejandra Bertuzzi

2012-09-01

Full Text Available In the present study, a better knowledge of the influence of plasticizer content, storage relative humidity and film thickness on the mechanical properties of high amylose corn starch based films gelatinized at low temperature, is presented. The mechanical properties, tensile strength and percentage of elongation at break of high amylose corn starch films plasticized with glycerol were evaluated using tension tests. The films exhibited an increase in elongation and a decrease in tensile strength with increasing plasticizer concentration. When the glycerol level was high, some fissures were detected in the dry films, possible due to phase separation (starch-glycerol phenomena. Film crystallinity is related to the reorganization capacity of the polymer chain, and thus the relative film crystallinity should increase with plasticizer content (glycerol and water. The mechanical properties were found to be strongly dependent on the water content due to the hydrophilic nature of starch films. The influence of moisture sorption on tensile strength was similar to that of plasticization with glycerol. The relationship between polymer chain mobility and water content explained this behavior. Elongation suffered a different effect and maximum values were reached at 45% relative humidity. The final drop in elongation was due to a softening of the structure at high relative humidity. The thicker the film the longer the drying time required, leading to greater relative crystallinity due to the corresponding increase in the possibility for chain reorganization. As a consequence, linear increases in tensile strength and elongation were observed with film thickness over the whole range studied (30 to 100 µm.No presente estudo, é apresentado um melhor conhecimento da influência do teor em plastificante, da umidade relativa de armazenamento e da espessura do filme nas propriedades mecânicas do filme baseado em amido de milho de alto conteúdo de amilose

Influence of nanoparticles on the properties of bionanocomposites from cassava starch

International Nuclear Information System (INIS)

Paglicawan, Marissa A.; Emolaga, Carlo S.; Navarro, Ma. Teresa V.; Celorico, Josefina; Basilia, Blessie A.

2015-01-01

Plastics are widely used packaging materials for food and non-food products due to their desirable material properties and low cost. However, the merits of plastic products have been overshadowed by its non-degradable nature, thereby leading to waste disposal problems. Because of the environmental problem, many researchers are facing to minimize non-degradable to biodegradable materials. Starch is one of the most promising natural polymers because of its inherent biodegradability, overwhelming abundance and its renewability. One of the abundant starch is cassava. The Manihot exculenta Crantz, is known as camoteng-kahoy or balinghoy in the Philippines. The production of thermoplastic starch (also known as plasticized starch or TPS) basically involves three essential components, namely: starch, plasticizer and thermomechanical energy. However, this material has high water solubility and may lose their mechanical properties in humid conditions. One of the possible ways to overcome this problem is through nanocomposite in which consist of a polymer matrix reinforced with nano-dimensional particles. This research involves the processing of cassava starch into thermoplastic starch for packaging application that can be biodegraded in soil or compostable after its usage. Thermoplastic starchs from cassava starch and different nanomaterials were processed by melt-blending method in a twin-screw extruder. The four nanofillers - nanoclay (NC), halloysite nanotube (HNT), nanozeolite (NZ), and nanocalcium carbonate (NCC) were incorporated into the starch matrix in a 3 phr concentration. The resulting biocomposites were characterized in terms of mechanical properties, morphology, thermal properties, moisture absorption, and crystallinity. The newly developed technology based on cassava starch/nano-scale particles nanocomposites upgrade the hdydrophylic and mechanical properties of starch based films. Homogeneously dispersing nanometer size materials, with high length

Influence of ensiling, exogenous protease addition, and bacterial inoculation on fermentation profile, nitrogen fractions, and ruminal in vitro starch digestibility in rehydrated and high-moisture corn.

Science.gov (United States)

Ferraretto, L F; Fredin, S M; Shaver, R D

2015-10-01

Exogenous protease addition may be an option to increase proteolysis of zein proteins and thus starch digestibility in rehydrated and high-moisture corn (HMC) ensiled for short periods. In addition, microbial inoculation may accelerate fermentation and increase acid production and thus increase solubilization of zein proteins. Four experiments were performed to evaluate the effect on fermentation profile, N fractions, and ruminal in vitro starch digestibility (ivSD) of the following: (1) rehydration and ensiling of dry ground corn; (2) exogenous protease addition to rehydrated un-ensiled and ensiled corn; (3) exogenous protease addition or inoculation in rehydrated ensiled corn; and (4) exogenous protease addition or inoculation in HMC. Experiments 1, 2, and 3 were performed with 7 treatments: dry ground corn (DGC); DGC rehydrated to a targeted dry matter content of 70% (REH); REH treated with exogenous protease (REH+); REH ensiled for 30 d (ENS); ENS treated with exogenous protease (ENS+); ENS treated with a microbial inoculant containing Lactobacillus plantarum, Lactobacillus casei, Enterococcus faecium, and Pediococcus sp. (ENSI); and ENS treated with exogenous protease and microbial inoculant (ENSI+). Experiment 1 compared DGC, REH, and ENS with ivSD being greater for ENS (64.9%) than DGC and REH (51.7% on average). Experiment 2 compared REH and ENS without or with exogenous protease addition (REH+ and ENS+, respectively). Ensiling and exogenous protease addition increased ivSD, but exogenous protease addition was more effective in ENS than REH (6.4 vs. 2.6 percentage unit increase). Experiment 3 compared the effects of exogenous protease addition and inoculation in ENS corn (ENS, ENS+, ENSI, and ENSI+). The addition of protease, but not inoculant, increased ivSD. Inoculation reduced pH and acetate, propionate, and ethanol concentrations, and increased lactate and total acid concentrations. In experiment 4, 8 treatments were a combination of HMC noninoculated

Preparation and Properties of Cassava Starch-based Wood Adhesives

Directory of Open Access Journals (Sweden)

Qing Xu

2016-06-01

Full Text Available A biodegradable, environmentally friendly starch-based wood adhesive with cassava starch as a raw material and butyl acrylate (BA as a co-monomer was synthesized. Results revealed that this cassava starch-based wood adhesive (SWA was more stable than corn starch-based wood adhesive, and its bonding performance was close to that of commercial PVAc emulsion, even after 90 days of storage. Further analysis found that the improved stability of the adhesive could be attributed to its low minimum film forming temperature (MFFT and glass transition temperature (Tg of cassava starch. Moreover, the amount of total volatile organic compounds (TVOCs emitted by the cassava starch-based wood adhesive were much lower than the Chinese national standard control criteria. Therefore, cassava SWA might be a potential alternative to traditional petrochemical-based wood adhesives.

The properties of two starch super absorbent polymers synthesized by gamma radiation

International Nuclear Information System (INIS)

Wang Changbao; Zhao Yongfu; Li Lili; Ji Ping; Shi Yan; Ge Cailin; Wang Zhidong

2013-01-01

Two types of super absorbent polymers were synthesized from corn starch, wheat starch and acrylic acid under gamma irradiation, without any initiator. The water absorption capacity of the super absorbent products were studied. The results indicated that the prepared polymer from wheat starch per gram could absorb 755 g distilled water, 249 g tap water, and 80 g 0.9% NaCl; and the polymer from corn starch per gram could absorb 747 g distilled water, 238 g tap water, and 84 g 0.9% NaCl. The absorption capacity of the two polymers was decreased quickly at first and then slow down with the concentration of NaCl solutions increased. The two polymers have similar absorption capacity in pH value between 4 and 11 for distilled water and at temperature between 4 and 60℃ for distilled water. The two polymers have good water retention properties in high temperature and pressure conditions. (authors)

Viability of bifidobacteria strains in yogurt with added oat beta-glucan and corn starch during cold storage.

Science.gov (United States)

Rosburg, Valerie; Boylston, Terri; White, Pamela

2010-06-01

Probiotics must be consumed at a level of 10(7) CFU/mL for successful colonization of the gut. In yogurts containing beneficial cultures, the survival of probiotic strains can quickly decline below this critical concentration during cold storage. We hypothesized that beta-glucan would increase the viability of bifidobacteria strains in yogurt during cold storage. Yogurts were produced containing 0.44% beta-glucan (concentrated or freeze-dried) extracted from whole oat flour and/or 1.33% modified corn starch, and bifidobacteria (B. breve or B. longum) at a concentration of at least 10(9) CFU/mL. All yogurts were stored at 4 degrees C. Bifidobacteria and yogurt cultures, Streptococcus thermophilus and Lactobacillus delbureckii subsp. bulgaricus, were enumerated from undisturbed aliquots before fermentation, after fermentation, and once a week for 5 wk. S. thermophilus and L. bulgaricus maintained a concentration of at least 10(8) CFU/mL in yogurts containing concentrated or freeze-dried beta-glucan regardless of starch addition, and in the control with no added beta-glucan or starch. Similarly, the probiotic, Bifidobacterium breve, survived above a therapeutic level in all treatments. The addition of beta-glucan prolonged the survival of Bifidobacterium longum at a concentration of at least 10(7) CFU/mL by up to 2 wk on average beyond the control. Further, the inclusion of concentrated beta-glucan in yogurt improved survival of B. longum above 10(7) CFU/mL by 1 wk longer than did freeze-dried beta-glucan. Study results suggest that beta-glucan has a protective effect on bifidobacteria in yogurt when stressed by low-temperature storage.

Investigations into the free-volume changes within starch/plasticizer/nanoclay systems using Positron Annihilation Lifetime Spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Liu, Huihua, E-mail: h.liu@federation.edu.au [School of Health Sciences, Federation University Australia, Ballarat, Vic (Australia); Chaudhary, Deeptangshu, E-mail: deepc@ers.com.au [ERS Environmental Risk Solutions PTY LTD, Perth, WA (Australia); Campbell, Colin, E-mail: colin.campbell@anu.edu.au [ARC Centre of Excellence for Antimatter-Matter Studies (CAMS), Research School of Physics and Engineering, Australian National University, Canberra (Australia); Roberts, Jason, E-mail: jxr107@physics.anu.edu.au [ARC Centre of Excellence for Antimatter-Matter Studies (CAMS), Research School of Physics and Engineering, Australian National University, Canberra (Australia); Buckman, Stephen, E-mail: stephen.buckman@anu.edu.au [ARC Centre of Excellence for Antimatter-Matter Studies (CAMS), Research School of Physics and Engineering, Australian National University, Canberra (Australia); Sullivan, James, E-mail: james.sullivan@anu.edu.au [ARC Centre of Excellence for Antimatter-Matter Studies (CAMS), Research School of Physics and Engineering, Australian National University, Canberra (Australia)

2014-11-14

The free-volume of a matrix is a fundamental parameter that relates to its molecular and bulk characteristics, such as crystalline change and glass transition behavior. In starch-based bionanocomposite, we investigated the effect of the addition of montmorillonite nanoclay (MMT) and food plasticizers (glycerol and sorbitol) on changes of molecular pore size (including pore volume and pore distribution) using the Positron Annihilation Lifetime Spectroscopy (PALS) method. The results demonstrated counter-intuitive impact of MMT on the total free-volume where the total free-volume increased within the polymeric matrix. When compared to the pure matrix free-volume, the addition of MMT also resulted in the appearance of a broader distribution of the void sizes. The plasticizers, on the other hand, apparently occupied the void spaces, and therefore decreased the free-volume of the matrix. Further, together with the small angle X-ray scattering (SAXS) analysis, we concluded that this is a result of interplay between the plasticizer-plasticizer interactions and the polymer–plasticizer interactions. For example, in the starch/glycerol/MMT system, the pore radii slightly decrease upon the increasing of glycerol amount (OG210 = O.27 nm and OG220 = 0.26 nm), but the relative weight did increase with the increasing glycerol concentration. However, increasing the sorbitol amount increased the pore size from 0.23 nm(OS210) to 0.28 nm(OS220). Furthermore, the addition MMT in the OS010 system, promote the emergence of a new dateable pore radius(0.90 nm), and the total weight significantly increased from 13.70 (OS010) to 19.5% (OS210). We suggest that the pore variation (size and distribution) due to the MMT and plasticizers are reflected in the polymer glass transition and crystallinity because ultimately, the, total free-volume is a reflection of level of interactions existing within the bulk of these nanocomposites. - Highlights: • PALS is applied to explore the

Physicochemical, Thermal, and Sensory Properties of Blue Corn (Zea Mays L.).

Science.gov (United States)

Mutlu, Ceren; Arslan-Tontul, Sultan; Candal, Cihadiye; Kilic, Ozlem; Erbas, Mustafa

2018-01-01

The aim of this study was to investigate some physicochemical and sensory properties of blue corn cultivated in Turkey. The length and width of the cob with kernels, hectoliter, and 1000-kernel weight of blue corn were measured as 7.66, 2.02 mm, 84.40 kg/100 L, and 44.27 g, respectively. The gelatinization onset, peak, and end temperatures were measured as 61.12 °C, 64.35 °C, and 75.65 °C, respectively. The water activity, moisture content, total protein, lipid, and crude fiber contents of the blue corn sample were detected as 0.44, 9.39%, 13.13%, 4.30%, and 2.68%, respectively. Total starch and resistant starch contents of blue corn were determined as 63.94% and 8.89%, respectively. Also, total monomeric anthocyanin content and antioxidant capacity of blue corn were detected as 915.43 mg CGE/kg and 7.99 μmol TE/g, respectively. Additionally, the major fatty acids detected in blue corn samples were palmitic, stearic, oleic, and linoleic acids. Blue corn can be utilized in the production of enjoyable and healthier snacks, such as popcorn and chips, because of its color and high phenolic, anthocyanin, and fiber contents. © 2017 Institute of Food Technologists®.

Production of modified starches by gamma irradiation

International Nuclear Information System (INIS)

Kang, Il-Jun; Byun, Myung-Woo; Yook, Hong-Sun; Bae, Chun-Ho; Lee, Hyun-Soo; Kwon, Joong-Ho; Chung, Cha-Kwon

1999-01-01

As a new processing method for the production of modified starch, gamma irradiation and four kinds of inorganic peroxides were applied to commercial corn starch. The addition of inorganic peroxides without gamma irradiation or gamma irradiation without the addition of inorganic peroxides effectively decreased initial viscosity, but did not sufficiently keep viscosity stable. The combination of adding ammonium persulfate (APS) and gamma irradiation showed the lowest initial viscosity and the best stability out of the tested four kinds of inorganic peroxides. Among the tested mixing methods of APS, soaking was found to be more effective than dry blending or spraying. Therefore, the production of modified starch with low viscosity as well as with sufficient viscosity stability became feasible by the control of gamma irradiation dose levels and the amount of added APS to starch

OPTIMIZATION OF TABLET FORMULATIONS BASED ON STARCH LACTOSE GRANULATIONS FOR USE IN TROPICAL COUNTRIES

NARCIS (Netherlands)

BOS, CE; BOLHUIS, GK; LERK, CF

1991-01-01

Several granulations consisting of alpha-lactose monohydrate 200 mesh and native starch (corn, potato, rice or tapioca) were prepared. The influence of starch concentration, storage temperature and relative humidity on the physical properties of the tablets prepared from these granulations was

Irradiation of starches for industrial uses: Chemical and physical effects

International Nuclear Information System (INIS)

Gonzalez, Maria E.

1999-01-01

Corn and cassava starches have been irradiated with gamma doses from 10 to 180 kGy and pastes have been prepared by boiling the starches in water. The rheological properties of the pastes have been determined showing that the 10 kGy dose reduces sharply the viscosity of the aqueous pastes. The solubility of the irradiated starches has been also studied. The cassava starch irradiated with 180 kGy is soluble in boiling water and remains soluble at room temperature. After some considerations on the chemical effects of the irradiation it is concluded that the irradiation technique is suitable to replace the chemical treatment in many industrial applications of the starch. (author)

Effect of gamma irradiation on thermophysical properties of plasticized starch and starch surfactant films

Science.gov (United States)

Cieśla, Krystyna; Watzeels, Nick; Rahier, Hubert

2014-06-01

In this work the influence of gamma irradiation on the thermomechanical properties of the films formed in potato starch-glycerol and potato starch-glycerol-surfactant systems were examined by Dynamic Mechanical Analysis, DMA, and Differential Scanning Calorimetry, DSC, and the results were correlated to the amount of the volatile fraction in the films.

In vitro ruminal fermentation kinetic of diets containing forage cactus with urea and different starch sources

Directory of Open Access Journals (Sweden)

Yann dos Santos Luz

2014-06-01

Full Text Available The study was conducted to evaluate fermentation kinetic of diets based on cactus forage enriched with urea and Tifton 85 hay, containing different starch sources, using semi-automated in vitro gas production technique. Treatments were disposed in a randomized block design, with four replications, where concentrates were formulated as follows: cassava roots (FSMa, semi flint corn grains (FSMiSD, dent corn grains (FSMiD and wheat bran (FTMa. All diets were formulated to obtain 15% of crude protein. Gas pressure were measured 2, 4, 6, 8, 10, 12, 15, 18, 21, 24, 30, 36, 48, 72 and 96 h after inoculation. For fast phase maximum gas volume (Vf1, both treatments containing corn did not differ (P>0.05. FTMa differed (P<0.05 from diets composed with corn, as main starch source. Specific degradation rate of fast fraction (Kd1 was higher (P<0.05 on FSMa and FTMa diets, compared with corn diets. Colonization time (L showed lower values (P<0.05 for FTMa diet. The lowest total gas production was observed on FTMa and the highest for FSMiD, varying from 225.49 to 268.31 mL/g, respectively. Cassava roots as starch source contributes to a faster fermentation, compared to both corns, allowing a better synchronization with faster degradation nitrogen sources.

Production of bioplastic from jackfruit seed starch (Artocarpus heterophyllus) reinforced with microcrystalline cellulose from cocoa pod husk (Theobroma cacao L.) using glycerol as plasticizer

Science.gov (United States)

Lubis, M.; Gana, A.; Maysarah, S.; Ginting, M. H. S.; Harahap, M. B.

2018-02-01

The production of bioplastic from jackfruit seed starch reinforced with microcrystalline cellulose (MCC) cocoa pod husk using glycerol as plasticizer was investigated to determine the most optimum mass and volume of MCC and glycerol in producing bioplastics. To produce MCC, Cocoa pod husk was subjected to alkali treatment, bleaching, and hydrochloric acid hydrolysis. The degree of crystallinity of MCC, were determined by XRD, functional group by FT-IR and morphologycal analysis by SEM. Analysis of bioplastic mechanical properties includes tensile strength and elongation at break based on ASTM D882 standard. Bioplastics were produced by casting method from jackfruit seed starch and reinforced with MCC from cocoa pod husk at starch mass to MCC ratio of 6:4, 7:3, 8:2, and 9:1, using glycerol as plasticizer at 20%, 25%, 30% (wt/v of glycerol to starch). From the result, the isolated MCC from cocoa pod husk were in a form of rod-like shape of length 5-10 µm with diameter 11.635 nm and 74% crystallinity. The highest tensile strength of bioplastics was obtained at starch to MCC mass ratio of 8:2, addition of 20% glycerol with measured tensile strength of 0.637 MPa and elongation at break of 7.04%. Transform infrared spectroscopy showed the functional groups of bioplastics, which the majority of O-H groups were found at the bioplastics with reinforcing filler MCC that represented substantial hydrogen bonds.

Corn fiber hulls as a food additive or animal feed

Science.gov (United States)

Abbas, Charles; Beery, Kyle E.; Cecava, Michael J.; Doane, Perry H.

2010-12-21

The present invention provides a novel animal feed or food additive that may be made from thermochemically hydrolyzed, solvent-extracted corn fiber hulls. The animal feed or food additive may be made, for instance, by thermochemically treating corn fiber hulls to hydrolyze and solubilize the hemicellulose and starch present in the corn fiber hulls to oligosaccharides. The residue may be extracted with a solvent to separate the oil from the corn fiber, leaving a solid residue that may be prepared, for instance by aggolmerating, and sold as a food additive or an animal feed.

Change in digestibility of gamma-irradiated starch by low temperature cooking

International Nuclear Information System (INIS)

Kume, T.; Ishigaki, I.; Rahman, S.

1988-01-01

Combination effect of irradiation and low temperature cooking on starch digestibility has been investigated as a basic research for application of radiosterilization on starch fermentation. The digestion of corn starch by glucoamylase after cooking at low temperature was enhanced by γ-irradiation and the required cooking temperature was decreased from 75-80 0 C to 65 0 C by 25 kGy. Gelatinization of starches except tapioca starch was enhanced by irradiation and it corresponds to the digestibility. The digestibility of potato starch which has a high viscosity was especially enhanced at low temperature cooking because the viscosity was markedly decreased by irradiation. These results show that the irradiation of starches is useful not only for the sterilization of fermentation broth but also for the enhancement of digestion. (orig.) [de

Change in digestibility of gamma-irradiated starch by low temperature cooking

Energy Technology Data Exchange (ETDEWEB)

Kume, T.; Ishigaki, I.; Rahman, S.

1988-04-01

Combination effect of irradiation and low temperature cooking on starch digestibility has been investigated as a basic research for application of radiosterilization on starch fermentation. The digestion of corn starch by glucoamylase after cooking at low temperature was enhanced by ..gamma..-irradiation and the required cooking temperature was decreased from 75-80/sup 0/C to 65/sup 0/C by 25 kGy. Gelatinization of starches except tapioca starch was enhanced by irradiation and it corresponds to the digestibility. The digestibility of potato starch which has a high viscosity was especially enhanced at low temperature cooking because the viscosity was markedly decreased by irradiation. These results show that the irradiation of starches is useful not only for the sterilization of fermentation broth but also for the enhancement of digestion.

Use of biomass energy. Saccharification of raw starch and ethanol fermentation

Energy Technology Data Exchange (ETDEWEB)

Ueda, S

1982-01-01

Raw starch was saccharified under acidic condition of pH 3.5 using black-koji amylase, and the resultant saccharidies were fermented to give ethanol in succession. White polished rice flour was fermented at 30 degrees C during the period of 7 to 10 days to give ethanol. Semi-continuous ethanol fermentation was carried out using corn starch and cassava starch. Batch ethanol fermentation was also carried out using cassava or sweet potato. Sweet potato was fermented using Rhizopus gluco-amylase. 11 references.

The effect of increasing chitosan on the characteristics of bioplastic from starch talas (Colocasia esculenta) using plasticizer sorbitol

Science.gov (United States)

Ginting, M. H. S.; Lubis, M.; Sidabutar, T.; Sirait, T. P.

2018-03-01

The aims of this research to determine the profile of starch gelatinization, bioplastic and the effect of increasing chitosan and sorbitol to the properties of tensile strength and elongation of break bioplastic. Preparation of bioplastics was used by casting method, that is 30% w/v solution of starch mixed with chitosan solution (0.5 w/v; 1 w/v; 1.5 w/v; 2 w/v; and 2.5 w/v) and plasticizer sorbitol (10 % w/w; 20 % w/w; 30 % w/w; 40 % w/w and 50 % w/w) were heated using a hotplate magnetic stirrer at 750C. The results of Rapid Visco Analyzer (RVA) obtained by starch and bioplastic gelatinization temperature of 72.94°C 77.72°C with peak viscosity 6632 cP and 3476 cP. Analysis of Fourier Transform Infrared (FTIR) and Scanning Electron Microscopy (SEM) obtained the change a functional group of bioplastic OH at wave number 3765 cm-1 and uneven chitosan distribution, and there is still an empty fraction. The addition of chitosan and sorbitol had an effect on tensile strength and elongation at break, tensile strength and elongation at break the highest of 8.36 MPa and 22.06% in starch composition 30%, 2.5 w/v chitosan and sorbitol 30% w/w.

Properties of foam and composite materials made o starch and cellulose fiber

Science.gov (United States)

Composite materials were made of starch and cellulose fibers. Pre-gelatinized starch was effective in dispersing pulp fiber in a starch matrix to form a viscous starch/fiber dough. The starch/fiber dough was a useful feedstock for various composite foam and plastic materials. Viscous blends of star...

Improvement of D-Ribose Production from Corn Starch Hydrolysate by a Transketolase-Deficient Strain Bacillus subtilis UJS0717

Science.gov (United States)

Wei, Zhuan; Zhou, Jue; Sun, WenJing; Cui, FengJie; Xu, QinHua; Liu, ChangFeng

2015-01-01

D-Ribose is a five-carbon sugar and generally used as an energy source to improve athletic performance and the ability. The culture conditions for maximum D-ribose production performance from cheap raw material corn starch hydrolysate were improved by using one-factor-at-a-time experiments and a three-level Box-Behnken factorial design. The optimal fermentation parameters were obtained as 36°C culture temperature, 10% inoculum volume, and 7.0 initial pH. The mathematical model was then developed to show the effect of each medium composition and their interactions on the production of D-ribose and estimated that the optimized D-ribose production performance with the concentration of 62.13 g/L, yield of 0.40 g/g, and volumetric productivity of 0.86 g/L·h could be obtained when the medium compositions were set as 157 g/L glucose, 21 g/L corn steep liquor, 3.2 g/L (NH4)2SO4, 1 g/L yeast extract, 0.05 g/L MnSO4·H2O, and 20 g/L CaCO3. These findings indicated the D-ribose production performance was significantly improved compared to that under original conditions. PMID:26759810

Enzymatic hydrolysis of corn bran arabinoxylan

DEFF Research Database (Denmark)

Agger, Jane

as a model substrate because it represents a readily available agroindustrial side product with upgrading potentials. Corn bran originates from the wet-milling process in corn starch processing, is the outmost layers of the corn kernel and is particularly rich in pentose monosaccharides comprising the major...... in a complex and ridig cell wall structure. This thesis contains a thorough examination of the monosaccharide and structural composition of corn bran, which is used to assess and apply the relevant mono component enzyme preparations. In this way, the aim is to obtain the most effective minimal enzymatic......, especially with respect to xylose and glucose release, but vast amounts of the valuable monosaccharides are lost during this pretreatment and this is especially evident for arabinose. From a scientific point of view acid catalysed pretreatment renders the substrate in a state of disruption where assessment...

UTILIZATION OF CORN STARCH AS SUBSTRATE FOR Я

African Journals Online (AJOL)

IITA

substrate, 10.1 X102 CFU/ml soluble starch and nutrient broth medium ... enzymatic activity with corresponding maltose yield of 46.4mg/ml and 68.0mg/ml .... stand for 15min at room temperature, the ... order to inactivated the beta amylase.

EFFECT OF ENDOSPERM HARDNESS ON AN ETHANOL PROCESS USING A GRANULAR STARCH HYDROLYZING ENZYME

Energy Technology Data Exchange (ETDEWEB)

Wang, P; W Liu, D B; Johnston, K D; Rausch, S J; Schmidt, M E; Tumbleson, V Singh

2010-01-01

Granular starch hydrolyzing enzymes (GSHE) can hydrolyze starch at low temperature (32°C). The dry grind process using GSHE (GSH process) has fewer unit operations and no changes in process conditions (pH 4.0 and 32°C) compared to the conventional process because it dispenses with the cooking and liquefaction step. In this study, the effects of endosperm hardness, protease, urea, and GSHE levels on GSH process were evaluated. Ground corn, soft endosperm, and hard endosperm were processed using two GSHE levels (0.1 and 0.4 mL per 100 g ground material) and four treatments of protease and urea addition. Soft and hard endosperm materials were obtained by grinding and sifting flaking grits from a dry milling pilot plant; classifications were confirmed using scanning electron microscopy. During 72 h of simultaneous granular starch hydrolysis and fermentation (GSHF), ethanol and glucose profiles were determined using HPLC. Soft endosperm resulted in higher final ethanol concentrations compared to ground corn or hard endosperm. Addition of urea increased final ethanol concentrations for soft and hard endosperm. Protease addition increased ethanol concentrations and fermentation rates for soft endosperm, hard endosperm, and ground corn. The effect of protease addition on ethanol concentrations and fermentation rates was most predominant for soft endosperm, less for hard endosperm, and least for ground corn. Samples (soft endosperm, hard endosperm, or corn) with protease resulted in higher (1.0% to 10.5% v/v) ethanol concentration compared to samples with urea. The GSH process with protease requires little or no urea addition. For fermentation of soft endosperm, GSHE dose can be reduced. Due to nutrients (lipids, minerals, and soluble proteins) present in corn that enhance yeast growth, ground corn fermented faster at the beginning than hard and soft endosperm.

Effect of pH on paste properties of irradiated corn starch by gamma-rays

International Nuclear Information System (INIS)

Kume, Tamikazu; Aoki, Shohei; Kobayashi, Nobuo; Okuaki, Akira.

1979-01-01

The degradation of starch by γ-irradiation and the effect of pH on gelatinization of starch after irradiation were investigated. Paste viscosities were markedly affected by pH on gelatinization and a decrease in the viscosity of irradiated starch was stimulated by increasing pH. On the other hand, the solubility of irradiated starch increased significantly at the high pH. The granule structure of irradiated starch easily disintegrated at alkaline pH. Remarkable dissolution from the surface of the irradiated starch granules was observed after heating at high pH only a filamentous network frame remained, but the unirradiated one collapsed and folded. It was seen that alkali treatment after irradiation reduces the required dose to obtain low viscosity starch. The required dose to produce a low viscosity starch, for example Ajinomoto Essan Sizer 600 grade, was ca. 3 Mrad at pH 11.0 and ca. 5 Mrad at pH 7.0, whereas it was ca. 7 Mrad without pH adjustment. (author)

INFLUENCE OF SILAGE ADDITIVES ON FERMENTATION OF HIGH MOISTURE CRIMPED CORN

Directory of Open Access Journals (Sweden)

Branislav Gálik

2009-03-01

Full Text Available The objective of this work was to find influence of different silage additives on silages fermentation and nutritional value made from high moisture crimped corn, which were conserved in semi experimental conditions. Three variants were examined, untreated control (C, and two experimental variants conserved by biological (variant A and chemical (variant B additives. The maize crimped corn was hermetically filled into plastic bins with the capacity 50 dm3. In silage conserved by additives was lower content of crude fibre (significantly in both experimental variants and higher content of nitrogen free extract, starch and total sugars (significantly in variant A established. In silages form both experimental variants we found significantly lower content of lactic acid. The highest concent we detected in silage conserved without additives. In silage conserved by biological inoculant we found lower content of acetic acid and higher content of butyric acid, but their content was generally very low. Additives used in the experiment decreased content of amonia (0.074 g.kg-1 in variant A and 0.095 g.kg-1 of dry matter in variant B and alcohols too.

Starch/fiber/poly(lactic acid) foam and compressed foam composites

Science.gov (United States)

Composites of starch, fiber, and poly(lactic acid) (PLA) were made using a foam substrate formed by dehydrating starch or starch/fiber gels. PLA was infiltrated into the dry foam to provide better moisture resistance. Foam composites were compressed into plastics using force ranging from 4-76MPa. Te...

Alteration of biomass composition in response to changing substrate particle size and the consequences for enzymatic hydrolysis of corn bran

DEFF Research Database (Denmark)

Agger, Jane; Meyer, Anne S.

2012-01-01

Corn bran is a by-product from corn starch processing. This work examined the effects of changing substrate particle size on enzymatic hydrolysis of both raw and pretreated destarched corn bran. The biomass composition of the corn bran varied between particle size fractions: The largest particles...

Enhanced mechanical and thermal properties of poly (vinyl alcohol)/corn starch blends by nanoclay intercalation.

Science.gov (United States)

Tian, Huafeng; Wang, Kai; Liu, Di; Yan, Jiaan; Xiang, Aimin; Rajulu, A Varada

2017-08-01

Poly (vinyl alcohol) (PVA)/corn starch blend films with enhanced properties were fabricated by melt processing and montmorillonite (MMT) reinforcing. It was revealed that strong hydrogen bonding occurred between the abundant OH groups of the matrix and polar SiOSi and OH groups of MMT. The highly exfoliated MMT nanolayers were randomly dispersed in the matrix containing MMT lower than 10wt%, whereas the intercalated structure was predominant with MMT content higher than 10wt%. With the increase of MMT, the glass transition temperature as well as equilibrium torque increased. The water sorption decreased and water resistant properties were improved with the incorporation of MMT due to the restricted swelling of the matrix by MMT nanolayers. Significant improvement in strength and flexibility were observed due to the fine dispersion of the MMT layers and the strong interaction between MMT and the matrix. The thermal stability was also improved. The MMT nanolayers could act as the heat and mass transport barriers and retard the thermal decomposition of the composites. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of maturity and hybrid on ruminal and intestinal digestion of corn silage in dry cows.

Science.gov (United States)

Peyrat, J; Baumont, R; Le Morvan, A; Nozière, P

2016-01-01

The aim of this study was to evaluate the effect of stage of maturity at harvest on extent of starch, neutral detergent fiber (NDF), and protein digestion, and rumen fermentation in dry cows fed whole-plant corn silage from different hybrids. Four nonlactating Holstein cows cannulated at the rumen and proximal duodenum were fed 4 corn silages differing in hybrid (flint vs. flint-dent) and maturity stage (early vs. late) in a 4 × 4 Latin square design. From early to late maturity, starch content increased (from 234.5 to 348.5 g/kg), whereas total-tract (99.7 to 94.5%) and ruminal starch digestibility (91.3 to 86.5%) decreased significantly. The decrease in ruminal starch digestibility with increasing maturity was similar between hybrids. No effects were found of maturity, hybrid, or maturity × hybrid interaction on total-tract NDF digestibility, ruminal NDF digestibility, true digestibility of N and organic matter in the rumen, or microbial synthesis. Harvesting at later maturity led to increased ruminal ammonia, total volatile fatty acid concentrations, and acetate/propionate ratio but not pH. This study concludes that delaying date of harvest modifies the proportions of digestible starch and NDF supplied to cattle. Adjusting date of corn harvest to modulate amount of rumen-digested starch could be used as a strategy to control nutrient delivery to ruminants. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Amylolysis of raw corn by Aspergillus niger for simultaneous ethanol fermentation

Energy Technology Data Exchange (ETDEWEB)

Han, I.Y.; Steinberg, M.P.

1987-01-01

The novelty of this approach was hydrolysis of the raw starch in ground corn to fermentable sugars that are simultaneously fermented to ethanol by yeast in a nonsterile environment. Thus, the conventional cooking step can be eliminated for energy conservation. A koji of Aspergillus niger grown on whole corn for 3 days was the crude enzyme source. A ratio of 0.2 g dry koji/g total solids was found sufficient. Optimum pH was 4.2. Ethanol concentration was 7.7% (w/w) in the aqueous phase with 92% raw starch conversion. Agitation increased rate. Sacharification was the rate-limiting step. The initial ethanol concentration preventing fermentation was estimated to be 8.3% by weight. (Refs. 96).

Morphology and mechanical properties of PA12/plasticized starch blends prepared by high-shear extrusion

International Nuclear Information System (INIS)

Teyssandier, F.; Cassagnau, P.; Gérard, J.F.; Mignard, N.; Mélis, F.

2012-01-01

Highlights: ► High shear rate processing was found to greatly impact PA12/starch blend morphologies. ► The morphology was observed to be stable under subsequent processing conditions. ► The mechanical properties of the blends under high-shear rate were greatly improved. ► Polymer blend preparation via high-shear processing has proved to be very effective. ► Finally, polymer blends with improved mechanical properties were obtained. - Abstract: PA12/plasticized starch blends (PA12/TPS) were prepared by high-shear twin screw extruder. The morphology development and the mechanical properties of the blends were investigated as a function of the apparent shear rate. High-shear processing has proved to be an efficient method to finely disperse thermoplastic starch in polyamide 12 matrix. Blends containing TPS domains with a size at the nano-scale (R n ∼ 150 nm) homogeneously dispersed in PA12 matrix were obtained. From a modeling point of view, the variation of the droplet radius is closer to the Wu's predictions compared to the Serpe's predictions. From the basic hypothesis of these models, it can be then assumed that compatibilization between both phases occurs during the blend processing. Furthermore, this morphology of the blends has been proved to be stable after a reprocessing step in an internal mixer most likely due to either strong hydrogen bonds between the hydroxyl groups of starch and amide groups of polyamide 12 or to potentially cross reactions between macroradicals accounting for in situ formation of graft copolymers with the potential function of compatibilizers. Mechanical properties of the blends were found to be strongly dependent on the shear rate parameter of blend processing as the mechanical properties increase with shear rate. In agreement to the blend morphology, the elongation at break of the blends was greatly improved attesting of a good adhesion between both phases.

Compression, Mechanical and Release Properties of Chloroquine ...

African Journals Online (AJOL)

Results: Tablet formulations containing trifoliate yam starch exhibited faster onset and higher amount of plastic deformation during compression than those containing corn starch. The crushing strength, disintegration and dissolution times of the tablets increased with binder concentration while friability values decreased.

Prececal digestibility of various sources of starch in minipigs with or without experimentally induced exocrine pancreatic insufficiency.

Science.gov (United States)

Mösseler, A; Kramer, N; Becker, C; Gregory, P C; Kamphues, J

2012-12-01

Low prececal digestibility of starch leads to a higher starch flux into the hindgut, causing a forced microbial fermentation, energy losses, and meteorism. For exocrine pancreatic insufficiency (EPI), lack of pancreatic amylase can be compensated mostly by hindgut fermentation of starch. Even in pigs with complete loss of pancreatic secretion, starch digestibility over the entire tract is reaching levels of controls. To optimize diets for human patients with EPI, the proportion of starch that is digested by the ileum is important. Minipigs were fitted with an ileocecal reentrant fistula (n = 8) to determine prececal digestibility of starch. In 5 minipigs the pancreatic duct was ligated (PL) to induce EPI; 3 minipigs served as controls (Con). Various starch sources were tested in a 1-d screening test; therefore, disappearance rate (DR) instead of digestibility was used. Test meals consisted of 169 g DM of a basal diet plus 67.5 g DM of the starch (without thermal treatment; purified; starch content of 89 to 94.5%) and Cr(2)O(3). The test meal contained (% of DM) starch, 67; crude fat, 1.69; CP, 15; crude fiber, 2.0; and Cr(2)O(3), 0.25. In PL, prececal DR of starch was lower than in Con (P 90%) but was lower (P < 0.05) for potato (Solanum tuberosum) starch (75.4%). In PL, prececal DR of starch was higher (P < 0.05) for wheat (Triticum aestivum) starch (61.2%) than corn (Zea mays) starch (43.0%) and rice (Oryza sativa) starch (29.2%) and intermediate for potato and field pea (Pisum sativum) starch. For patients with EPI, wheat starch seems favorable due to the higher prececal digestibility whereas raw corn and rice starch should be avoided.

Effects of water on starch-g-polystyrene and starch-g-poly(methyl acrylate) extrudates

International Nuclear Information System (INIS)

Henderson, A.M.; Rudin, A.

1982-01-01

Polystyrene and poly(methyl acrylate) were grafted onto wheat starch by gamma radiation and chemical initiation, respectively. The respective percent add-on values were 46 and 45; 68% of the polystyrene formed was grafted to starch, and corresponding proportion of poly(methyl acrylate) was 41%. The molecular weight distributions of the homopolymer and graft portions were characterized, and extrusion conditions were established for production of ribbon samples of starch-g-PS and starch-g-PMA. Both copolymer types were considerably weakened by soaking in water, and this effect was more immediate and drastic for starch-g-poly(methyl acrylate). Both graft copolymers regained their original tensile strengths on drying, but the poly(methyl acrylate) specimens did not recover their original unswollen dimensions and retained high breaking elongations characteristic of soaked specimens. Tensile and dynamic mechanical properties of extruded and molded samples of both graft polymers are reported, and plasticizing effects of water are summarized

Agro-industrial residues and starch for growth and co-production of polyhydroxyalkanoate copolymer and α-amylase by Bacillus sp. CFR-67

Directory of Open Access Journals (Sweden)

T. R. Shamala

2012-09-01

Full Text Available Polyhydroxyalkanoates (PHA and α-amylase (α-1,4 glucan-4-glucanohydrolase, E.C. 3.2.1.1 were co-produced by Bacillus sp. CFR-67 using unhydrolysed corn starch as a substrate. Bacterial growth and polymer production were enhanced with the supplementation of hydrolysates of wheat bran (WBH or rice bran (RBH individually or in combination (5-20 g L-1, based on weight of soluble substrates-SS. In batch cultivation, a mixture of WBH and RBH (1:1, 10 g L-1 of SS along with ammonium acetate (1.75 g L-1 and corn starch (30 g L-1 produced maximum quantity of biomass (10 g L-1 and PHA (5.9 g L-1. The polymer thus produced was a copolymer of polyhydroxybutyrate-co-hydroxyvalerate of 95:5 to 90:10 mol%. Presence of WBH and corn starch (10-50 g L-1 in the medium enhanced fermentative yield of α-amylase (2-40 U mL-1 min-1. The enzyme was active in a wide range of pH (4-9 and temperature (40-60ºC. This is the first report on simultaneous production of copolymer of bacterial PHA and α-amylase from unhydrolysed corn starch and agro-industrial residues as substrates.

Sixth taste – starch taste?

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Zygmunt Zdrojewicz

2017-06-01

Full Text Available Scientists from Oregon State University, USA, came up with the newest theory of the sixth taste – starch taste that might soon join the basic five tastes. This argument is supported by studies done on both animals and humans, the results of which seem to indicate the existence of separate receptors for starch taste, others than for sweet taste. Starch is a glucose homopolymer that forms an α-glucoside chain called glucosan or glucan. This polysaccharide constitutes the most important source of carbohydrates in food. It can be found in groats, potatoes, legumes, grains, manioc and corn. Apart from its presence in food, starch is also used in textile, pharmaceutical, cosmetic and stationery industries as well as in glue production. This polysaccharide is made of an unbranched helical structure – amylose (15–20%, and a structure that forms branched chains – amylopectin (80–85%. The starch structure, degree of its crystallisation or hydration as well as its availability determine the speed of food-contained starch hydrolysis by amylase. So far, starch has been considered tasteless, but the newest report shows that for people of different origins it is associated with various aliments specific for each culture. Apart from a number of scientific experiments using sweet taste inhibitors, the existence of the sixth taste is also confirmed by molecular studies. However, in order to officially include starch taste to the basic human tastes, it must fulfil certain criteria. The aim of the study is to present contemporary views on starch.

Effect of antimicrobial on mechanical, barrier and optical properties of corn starch based self-supporting edible film

Directory of Open Access Journals (Sweden)

Tanima Chowdhury

2013-10-01

Full Text Available Antimicrobials like potassium sorbate, sodium propionate, and benzoic acid were incorporated in corn starch based formulation to investigate their effect on mechanical, water vapour barrier and optical properties of the developed self supporting edible film. The film was prepared by casting technique. When incorporated at 1.40% and above, potassium sorbate decreased the tensile strength (about 22% and increased the elongation (about 55% of control film; whereas, it increased the water vapour permeability by 15% only when added at 2.66%. At 2.66%, benzoic acid reduced the tensile strength by 24% and sodium propionate increased elongation by 17%. These two antimicrobials did not change the water vapour permeability. However, all the three antimicrobials adversely affected the optical properties by decreasing the whiteness index, increasing yellowness index, and reducing the surface gloss, with potassium sorbate showing the maximum effect. Among the three antimicrobials, sodium propionate appeared to be the best with minimum deterioration of film properties.

The relationship between absorbency and density of bioplastic film made from hydrolyzed starch

Science.gov (United States)

Singan, Grace; Chiang, Liew Kang

2017-12-01

Water absorption in polymer blends such as starch-based bioplastic films is important to evaluate the stability characteristics of such films in water that will affect their long-term performance in final products. In this study, the absorbency of starch-based bioplastic films made from potato, cassava, and corn starches that have went through the hydrolysis process first to alter its characteristics and properties in terms of granular swelling and hydrophilicity behaviour. The final results showed that hydrolyzed cassava bioplastic film has the ability to absorb more water compared to hydrolyzed potato and corn bioplastic films. The reading of hydrolyzed cassava bioplastic film on the seventh day of immersion for all ratios were between 87.83 % to 131.29 %, while for hydrolyzed potato bioplastic films was 69.48 % to 92.41 % and hydrolyzed corn bioplastic films was 66.28 % to 74.18 %. Meanwhile, the density analysis was evaluated to determine its physical properties towards moisture condition. The results showed that the hydrolyzed cassava bioplastic films have higher density compared to the other two, which indicated that it is a more favourable raw material to produce biodegradable planting pot due to its ability to absorb more water. Hence, still manage to retain its shape with low brittle surface.

A laser optical method for detecting corn kernel defects

Energy Technology Data Exchange (ETDEWEB)

Gunasekaran, S.; Paulsen, M. R.; Shove, G. C.

1984-01-01

An opto-electronic instrument was developed to examine individual corn kernels and detect various kernel defects according to reflectance differences. A low power helium-neon (He-Ne) laser (632.8 nm, red light) was used as the light source in the instrument. Reflectance from good and defective parts of corn kernel surfaces differed by approximately 40%. Broken, chipped, and starch-cracked kernels were detected with nearly 100% accuracy; while surface-split kernels were detected with about 80% accuracy. (author)

Fate of Fumonisin B1 in Naturally Contaminated Corn during Ethanol Fermentation

OpenAIRE

Bothast, R. J.; Bennett, G. A.; Vancauwenberge, J. E.; Richard, J. L.

1992-01-01

Two lots of corn naturally contaminated with fumonisin B1 (15 and 36 ppm) and a control lot (no fumonisin B1 detected) were used as substrates for ethanol production in replicate 8.5-liter yeast fermentations. Ethanol yields were 8.8% for both the control and low-fumonisin corn, while the high-fumonisin corn contained less starch and produced 7.2% ethanol. Little degradation of fumonisin occurred during fermentation, and most was recovered in the distillers' grains, thin stillage, and distill...

Performance of high amylose starch-composited gelatin films influenced by gelatinization and concentration.

Science.gov (United States)

Wang, Wenhang; Wang, Kun; Xiao, Jingdong; Liu, Yaowei; Zhao, Yana; Liu, Anjun

2017-01-01

In order to study the impact of starch in film performance, high amylose corn starch was composited in gelatin films under different gelatinization conditions and, in high and low concentrations (10 and 50wt.%). It was found that hot water gelatinized starch (Gel-Shw) increased film mechanical strength and was dependent upon the starch concentration. The addition of an alkali component to the starch significantly enhanced the swelling of the starch granules and expedited the gelatinization process. Incorporation of starch, especially the alkalized starch (Sha), into the gelatin films decreased film solubility which improved its water resistance and water vapor permeability (WVP). Multiple techniques (DSC, TGA, FT-IR, and XRD) were used to characterize the process and results, including the crosslinking of the dissolved starch molecules and the particles formed from gelatinized starch during retrogradation process, which played an important role in improving the thermal stability of the composited gelatin films. Overall, the starch-gelatin composition provides a potential approach to improve gelatin film performance and benefit its applications in the food industry. Copyright © 2016 Elsevier B.V. All rights reserved.

Physicochemical properties of different corn varieties by principal components analysis and cluster analysis

International Nuclear Information System (INIS)

Zeng, J.; Li, G.; Sun, J.

2013-01-01

Principal components analysis and cluster analysis were used to investigate the properties of different corn varieties. The chemical compositions and some properties of corn flour which processed by drying milling were determined. The results showed that the chemical compositions and physicochemical properties were significantly different among twenty six corn varieties. The quality of corn flour was concerned with five principal components from principal component analysis and the contribution rate of starch pasting properties was important, which could account for 48.90%. Twenty six corn varieties could be classified into four groups by cluster analysis. The consistency between principal components analysis and cluster analysis indicated that multivariate analyses were feasible in the study of corn variety properties. (author)

Production of starch with antioxidative activity by baking starch with organic acids.

Science.gov (United States)

Miwa, Shoji; Nakamura, Megumi; Okuno, Michiko; Miyazaki, Hisako; Watanabe, Jun; Ishikawa-Takano, Yuko; Miura, Makoto; Takase, Nao; Hayakawa, Sachio; Kobayashi, Shoichi

2011-01-01

A starch ingredient with antioxidative activity, as measured by the DPPH method, was produced by baking corn starch with an organic acid; it has been named ANOX sugar (antioxidative sugar). The baking temperature and time were fixed at 170 °C and 60 min, and the organic acid used was selected from preliminary trials of various kinds of acid. The phytic acid ANOX sugar preparation showed the highest antioxidative activity, but the color of the preparation was almost black; we therefore selected L-tartaric acid which had the second highest antioxidative activity. The antioxidative activity of the L-tartaric acid ANOX sugar preparation was stable against temperature, light, and enzyme treatments (α-amylase and glucoamylase). However, the activity was not stable against variations in water content and pH value. The antioxidative activity of ANOX sugar was stabilized by treating with boiled water or nitrogen gas, or by pH adjustment.

Effect of extrusion process on the functional properties of high amylose corn starch edible films and its application in mango (Mangifera indica L.) cv. Tommy Atkins.

Science.gov (United States)

Calderón-Castro, Abraham; Vega-García, Misael Odín; de Jesús Zazueta-Morales, José; Fitch-Vargas, Perla Rosa; Carrillo-López, Armando; Gutiérrez-Dorado, Roberto; Limón-Valenzuela, Víctor; Aguilar-Palazuelos, Ernesto

2018-03-01

Starch is an attractive raw material as ingredient for edible film manufacture because of its low cost, abundant availability, renewability, and biodegradability. Nevertheless, starch based films exhibit several disadvantages such as brittleness and poor mechanical and barrier properties, which restrict its application for food packaging. The use of the extrusion technology as a pretreatment of the casting technique to change the starch structure in order to obtain edible films, may constitute an alternative to generate coatings with good functional properties and maintain longer the postharvest quality and shelf life of fruits. For this reason, the objective of this study was to optimize the conditions of an extrusion process to obtain a formulation of modified starch to elaborate edible films with good functional properties using the casting technique and assess the effect during the storage when applied on a model fruit. The best conditions of the extrusion process and concentration of plasticizers were obtained using response surface methodology. From optimization study, it was found that appropriate conditions to obtain starch edible films with the best mechanical and barrier properties were an extrusion temperature of 100 °C and a screw speed of 120 rpm, while the glycerol content was 16.73%. Also, once applied in fruit, the loss of quality attributes was diminished.

Fragrant starch-based films with limonene

Directory of Open Access Journals (Sweden)

Adrian K. Antosik

2017-02-01

Full Text Available Novel fragrant starch-based films with limonene were successfully prepared. Biodegradable materials of natural origin were used and the process was relatively simple and inexpensive. The effect of limonene on physicochemical properties of starch-based films (moisture absorption, solubility in water, wettability, mechanical properties were compared to glycerol plasticized system. Taking into consideration that the obtained materials could also exhibit bactericidal and fungicidal properties, the studies with Escherichia coli, Candida albicans and Aspergillus niger were performed. Such a material could potentially find application in food packaging (e.g. masking unpleasant odors, hydrophilic starch film would prevent food drying, or in agriculture (e.g. for seed encapsulated tapes.

Preparation and characterization of poly(acrylic acid)—corn starch blend for use as chemical sand-fixing materials

Science.gov (United States)

Dang, Xugang; Chen, Hui; Shan, Zhihua

2017-07-01

One chemical sand-fixing materials based on poly(acrylic acid)-corn starch (PACS) blend was studied in this work. The PACS blend was prepared by solution mixing method between PA and CS. In order to prepare sand-fixing materials for environmental applications using the well-established method of spraying evenly PACS blend solution on the surfaces of fine sand. Fourier transform infrared spectroscopy (FT-IR) revealed the existence of the intermolecular interactions between the blend components. Scanning electron microscope (SEM) analysis showed a continuous phase of blend, and it also showed the good sand-fixing capacity. The test results of hygroscopicity and water retention experiments indicated that the blends had excellent water-absorbing and water-retention capacity. The results of contact angle measurements between the PACS solutions and fine sand showed that the PACS blend has a satisfactory effect on fine sand wetting. And the PACS, as a sand-fixation material, has excellent sand-fixation rate up to 99.5%.

Aflatoxin contamination of developing corn kernels.

Science.gov (United States)

Amer, M A

2005-01-01

Preharvest of corn and its contamination with aflatoxin is a serious problem. Some environmental and cultural factors responsible for infection and subsequent aflatoxin production were investigated in this study. Stage of growth and location of kernels on corn ears were found to be one of the important factors in the process of kernel infection with A. flavus & A. parasiticus. The results showed positive correlation between the stage of growth and kernel infection. Treatment of corn with aflatoxin reduced germination, protein and total nitrogen contents. Total and reducing soluble sugar was increase in corn kernels as response to infection. Sucrose and protein content were reduced in case of both pathogens. Shoot system length, seeding fresh weigh and seedling dry weigh was also affected. Both pathogens induced reduction of starch content. Healthy corn seedlings treated with aflatoxin solution were badly affected. Their leaves became yellow then, turned brown with further incubation. Moreover, their total chlorophyll and protein contents showed pronounced decrease. On the other hand, total phenolic compounds were increased. Histopathological studies indicated that A. flavus & A. parasiticus could colonize corn silks and invade developing kernels. Germination of A. flavus spores was occurred and hyphae spread rapidly across the silk, producing extensive growth and lateral branching. Conidiophores and conidia had formed in and on the corn silk. Temperature and relative humidity greatly influenced the growth of A. flavus & A. parasiticus and aflatoxin production.

Mechanical properties of bioplastics cassava starch film with Zinc Oxide nanofiller as reinforcement

Science.gov (United States)

Harunsyah; Yunus, M.; Fauzan, Reza

2017-06-01

This study focuses on investigating the influence of zinc oxide nanofiller on the mechanical properties of bioplastic cassava starch films. Bioplastic cassava starch film-based zinc oxide reinforced composite biopolymeric films were prepared by casting technique. The content of zinc oxide in the bioplastic films was varied from 0.2%, 0.4%, 0.6%, 0.8% and 1.0% (w/w) by weight of starch. Surface morphologies of the composites bioplastic films were examined by scanning electron microscope (SEM).The result showed that the Tensile strength (TS) was improved significantly with the additional of zinc oxide but the elongation at break (EB %) of the composites was decreased. The maximum tensile strength obtained was 22.30 kgf / mm on the additional of zinc oxide by 0.6% and plastilizer by 25%. Based on data of FTIR, the produced film plastic did not change the group function and it can be concluded that theinteraction in film plastic produced was only a physical interaction. Biodegradable plastic film based on cassava starch-zinc oxide and plasticizer glycerol showed that interesting mechanical properties being transparent, clear, homogeneous, flexible, and easily handled.

Hot-melt extrusion of sugar-starch-pellets.

Science.gov (United States)

Yeung, Chi-Wah; Rein, Hubert

2015-09-30

Sugar-starch-pellets (syn. sugar spheres) are usually manufactured through fluidized bed granulation or wet extrusion techniques. This paper introduces hot-melt extrusion (HME) as an alternative method to manufacture sugar-starch-pellets. A twin-screw extruder coupled with a Leistritz Micro Pelletizer (LMP) cutting machine was utilized for the extrusion of different types (normal-, waxy-, and high-amlyose) of corn starch, blended with varying amounts of sucrose. Pellets were characterized for their physicochemical properties including crystallinity, particle size distribution, tensile strength, and swelling expansion. Furthermore, the influence of sugar content and humidity on the product was investigated. Both sucrose and water lowered the Tg of the starch system allowing a convenient extrusion process. Mechanical strength and swelling behavior could be associated with varying amylose and amylopectin. X-ray powder diffractometric (XRPD) peaks of increasing sucrose contents appeared above 30%. This signified the oversaturation of the extruded starch matrix system with sucrose. Otherwise, had the dissolved sucrose been embedded into the molten starch matrix, no crystalline peak could have been recognized. The replacement of starch with sucrose reduced the starch pellets' swelling effect, which resulted in less sectional expansion (SEI) and changed the surface appearance. Further, a nearly equal tensile strength could be detected for sugar spheres with more than 40% sucrose. This observation stands in good relation with the analyzed values of the commercial pellets. Both techniques (fluidized bed and HME) allowed a high yield of spherical pellets (less friability) for further layering processes. Thermal influence on the sugar-starch system is still an obstacle to be controlled. Copyright © 2015 Elsevier B.V. All rights reserved.

Preparation and characterization of dialdehyde starch by one-step acid hydrolysis and oxidation.

Science.gov (United States)

Zuo, Yingfeng; Liu, Wenjie; Xiao, Junhua; Zhao, Xing; Zhu, Ying; Wu, Yiqiang

2017-10-01

Dialdehyde starch was prepared by one-step synthesis of acid hydrolysis and oxidation, using corn starch as the raw material, sodium periodate (NaIO 4 ) as the oxidant, and hydrochloric acid (HCl) as the acid solution. The prepared dialdehyde starch was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and gel permeation chromatography (GPC). The results confirmed that oxidation occurred between the starch and NaIO 4 . The acid hydrolysis reaction reduced the molecular weight of starch and effectively improved the aldehyde group contents (92.7%). Scanning electron microscope (SEM) analysis indicated that the average particle size decreased after acid hydrolysis and oxidation reaction. X-ray diffraction (XRD) and thermal gravimetric analyzer (TGA) analysis demonstrated that the crystallinity of the obtained dialdehyde starch showed a downward trend and a decelerated thermal decomposition rate. The starch after acid hydrolysis and oxidation exhibited lower hot paste viscosity and higher reactivity. Copyright © 2017. Published by Elsevier B.V.

A structured approach to target starch solubilisation and hydrolysis for the sugarcane industry.

Science.gov (United States)

Cole, Marsha R; Rose, Ingrid; Chung, Yoo Jin; Eggleston, Gillian

2015-01-01

In sugarcane processing, starch is considered an impurity that negatively affects processing and reduces the quality of the sugar end-product. In the last decade, there has been a general world-wide increase in starch concentrations in sugarcane. Industrial α-amylases have been used for many years to mitigate issues arising from starch in the sugarcane industry. Mixed results have prompted further studies of the behaviour of different physical forms of starch and their interactions with α-amylases during processing. By using corn starch as a reference in model juices and syrups, processing parameters, activities, and hydrolysis of insoluble, swollen, and soluble starch forms were evaluated for two commercial α-amylases with high (HT) and intermediate (IT) temperature stability, respectively. The ability of starch to solubilise across a sugarcane factory is largely limited by increased Brix values. Optimum target locations and conditions for the application of α-amylases in sugarcane processing are discussed in detail. Published by Elsevier Ltd.

Fate of Fumonisin B1 in Naturally Contaminated Corn during Ethanol Fermentation

Science.gov (United States)

Bothast, R. J.; Bennett, G. A.; Vancauwenberge, J. E.; Richard, J. L.

1992-01-01

Two lots of corn naturally contaminated with fumonisin B1 (15 and 36 ppm) and a control lot (no fumonisin B1 detected) were used as substrates for ethanol production in replicate 8.5-liter yeast fermentations. Ethanol yields were 8.8% for both the control and low-fumonisin corn, while the high-fumonisin corn contained less starch and produced 7.2% ethanol. Little degradation of fumonisin occurred during fermentation, and most was recovered in the distillers' grains, thin stillage, and distillers' solubles fractions. No toxin was detected in the distilled alcohol or centrifuge solids. Ethanol fermentation of fumonisin-contaminated corn coupled with effective detoxification of distillers' grains and aqueous stillage is suggested as a practical process strategy for salvaging contaminated corn. PMID:16348623

Effect of ionizing radiation on the properties of prepared plastic/starch blends and their applications as biodegradable materials

International Nuclear Information System (INIS)

Khalil, S.A.

2010-01-01

Blends based on different ratios of plasticised starch (PLST), low density poly-ethyleen (LDPE) were prepared by mixing in extrouder. The LDPE/PLST/POMA (poly-olefin maleic anhydride) and LDPE/PLST/TMPTA (tri-methylol propane tri-acrylate) were exposed to different doses of electron beam. The effect of mixing and E-Beam irradiation on the thermal, mechanical, water absorption, and structure morphology properties were investigated. The results showed that the addition of compatibilizers and E-Beam irradiation improve all the physical properties, which provides suitable material based on natural polymer for biodegradable plastic.

Progress in the production of bioethanol on starch-based feedstocks

Directory of Open Access Journals (Sweden)

Dragiša Savić

2009-10-01

Full Text Available Bioethanol produced from renewable biomass, such as sugar, starch, or lignocellulosic materials, is one of the alternative energy resources, which is both renewable and environmentally friendly. Although, the priority in global future ethanol production is put on lignocellulosic processing, which is considered as one of the most promising second-generation biofuel technologies, the utilizetion of lignocellulosic material for fuel ethanol is still under improvement. Sugar- based (molasses, sugar cane, sugar beet and starch-based (corn, wheat, triticale, potato, rice, etc. feedstock are still currently predominant at the industrial level and they are, so far, economically favorable compared to lingocelluloses. Currently, approx. 80 % of total world ethanol production is obtained from the fermentation of simple sugars by yeast. In Serbia, one of the most suitable and available agricultural raw material for the industrial ethanol production are cereals such as corn, wheat and triticale. In addition, surpluses of this feedstock are being produced in our country constantly. In this paper, a brief review of the state of the art in bioethanol production and biomass availability is given, pointing out the progress possibilities on starch-based production. The progress possibilities are discussed in the domain of feedstock choice and pretreatment, optimization of fermentation, process integration and utilization of the process byproducts.

Evaluation of thermoplastic starch/MMT nanocomposites by nuclear magnetic resonance (NMR)

International Nuclear Information System (INIS)

Schlemmer, D.; Rodrigues, Tiago C.A.F.; Resck, I.S.; Sales, M.J.A.

2010-01-01

Starch has been studied for replace petrochemical plastics for short shelf life. However, the starch films have limitations: sensitivity to moisture and poor mechanical strength. This can be improved by incorporating loads such as montmorillonite, forming nanocomposites. Nanocomposites were prepared with 1, 3, 5 and 10% of montmorillonite, using vegetable oils of Brazilian Cerrado as plasticizers. The NMR spectra of oils are similar, but the intensities of the signals varying with the proportion of fatty acids. The molar mass of the oils was also calculated by NMR. The spectrum of CP/MAS 13 C NMR for starch presented a duplet in 97 and 98 ppm, on the amorphous domains of C-1, indicating a crystal type A. The spectra of the nanocomposites are similar to those of starch and oils. No new peaks appear, suggesting that there are no strong chemical bonds between components. (author)

Characteristics of raw starch degrading alpha-amylase from Bacillus aquimaris MKSC 6.2 associated with soft coral Sinularia sp.

NARCIS (Netherlands)

Puspasari, Fernita; Nurachman, Zeily; Noer, Achmad Saefuddin; Radjasa, Ocky Karna; van der Maarel, Marc J. E. C.; Natalia, Dessy

Partially purified alpha-amylase from Bacillus aquimaris MKSC 6.2, a bacterium isolated from a soft coral Sinularia sp., Merak Kecil Island, West Java, Indonesia, showed an ability to degrade raw corn, rice, sago, cassava, and potato starches with adsorption percentage in the range of 65-93%. Corn

Evaluation of Starch Biodegradable Plastics Derived from Cassava ...

African Journals Online (AJOL)

BSN

2 Molecular Bio/Sciences Limited, 124 MCC Road, Calabar, Nigeria. Abstract ... cassava starch is a pure, natural biopolymer that is suitable for .... matter of fact, Ohtaki and Nakasaki (2000) reported that ... Chemistry and. Industry 31: 7 - 9.

The effect of amino acids on lipid production and nutrient removal by Rhodotorula glutinis cultivation in starch wastewater.

Science.gov (United States)

Liu, Meng; Zhang, Xu; Tan, Tianwei

2016-10-01

In this paper, the components of amino acids in mixed starch wastewater (corn steep water/corn gluten water=1/3, v/v) were analyzed by GC-MS. Effects of amino acids on lipid production by Rhodotorula glutinis and COD removal were studied. The results showed that mixed starch wastewater contained 9 kinds of amino acids and these amino acids significantly improved the biomass (13.63g/L), lipid yield (2.48g/L) and COD removal compared to the basic medium (6.23g/L and 1.56g/L). In a 5L fermentor containing mixed starch wastewater as substrate to culture R. glutinis, the maximum biomass, lipid content and lipid yield reached 26.38g/L, 28.90% and 7.62g/L, with the associated removal rates of COD, TN and TP reaching 77.41%, 69.12% and 73.85%, respectively. The results revealed a promising approach for lipid production with using amino acids present in starch wastewater as an alternative nitrogen source. Copyright © 2016 Elsevier Ltd. All rights reserved.

Physical and mechanical properties of biobased materials - Starch polylactate and polyhydroxybutyrate

DEFF Research Database (Denmark)

Bergenholtz, Karina P.; Nielsen, Per Væggemose; Olsen, M.B.

2001-01-01

Commercial and semi-commercial biobased materials (Polylactate, PLA, polyhydroxybutyrate, PHB, wheat starch and corn starch) were investigated. Physical and mechanical characterisation (tensile strength, elongation, tear strength, compression, gas permeability (CO2 and O-2) and water vapour...... permeability (WVP)) was examined. Tests on both films and cups show potential use of these materials for primary food packaging, especially PLA and PHB. An interesting O-2:CO2 permeability ratio (1:7 to 1:12) was seen, which make these materials suitable for packaging of food with high respiration...

Gamma-irradiated cationic starches: Paper surface-sizing agents

International Nuclear Information System (INIS)

Hofreiter, B.T.; Heath, H.D.; Schulte, M.I.; Phillips, B.S.

1981-01-01

Cationic starches, precisely depolymerized by gamma-irradiation ( 60 Co), were dispersed in mild alkali and evaluated as surface sizes for bond paper on a pilot paper machine. The irradiated products had excellent dispersion properties, were well retained on fibers when sized wastepaper (broke) was repulped and had an ability to enhance paper properties that was comparable to that of starch-based materials used commercially. A yellow corn flour, cationized by an essentially dry reaction process recently developed at this Center, was also radiolyzed and evaluated as a size. This latter product was unique in that all drying steps were eliminated in the preparation of a cationic ceral product of reduced viscosity. (orig.) [de

Synthesis and characterization of polystyrene-starch polyblend

International Nuclear Information System (INIS)

Tetty Kemala; M Syaeful Fahmi; Suminar S Achmadi

2010-01-01

Polystyrene foam (PS) is a polymer that is widely used but not biodegradable. Therefore, PS-starch polyblend was developed. In this research the effect of glycerol as plasticizer was evaluated based on mechanical and thermal analyses. PS-starch polyblends were produced by mixing PS and starch solution with composition ratios of 60:40, 65:35, 70:30, 75:25, and 80:20 percent by weight. Polylactic acid (20 %) was added as compatibilizer. The polyblends were analyzed its tensile strength, thermal properties, and density. The PS-starch polyblends were white opaque in color and fragile. The properties of tensile strength and density of the polyblends were in the range of that of pure PS. The tensile strength and density increases as PS constituents increasing with the best composition ratio of 80 PS to 20 of starch. Peak of glass transition and melting point seen a single on composition ration 80 PS to 20 of starch. Additional amount of glycerol did not affect the thermal property, but has caused a slight decrease in tensile strength and density. (author)

Impact of amylosucrase modification on the structural and physicochemical properties of native and acid-thinned waxy corn starch.

Science.gov (United States)

Zhang, Hao; Zhou, Xing; He, Jian; Wang, Tao; Luo, Xiaohu; Wang, Li; Wang, Ren; Chen, Zhengxing

2017-04-01

Recombinant amylosucrase from Neisseria polysaccharea was utilized to modify native and acid-thinned starches. The molecular structures and physicochemical properties of modified starches were investigated. Acid-thinned starch displayed much lower viscosity after gelatinization than did the native starch. However, the enzyme exhibited similar catalytic efficiency for both forms of starch. The modified starches had higher proportions of long (DP>33) and intermediate chains (DP 13-33), and X-ray diffraction showed a B-type crystalline structure for all modified starches. With increasing reaction time, the relative crystallinity and endothermic enthalpy of the modified starches gradually decreased, whereas the melting peak temperatures and resistant starch contents increased. Slight differences were observed in thermal parameters, relative crystallinity, and branch chain length distribution between the modified native and acid-thinned starches. Moreover, the digestibility of the modified starches was not affected by acid hydrolysis pretreatment, but was affected by the percentage of intermediate and long chains. Copyright © 2016 Elsevier Ltd. All rights reserved.

Preparation of donut-shaped starch microparticles by aqueous-alcoholic treatment.

Science.gov (United States)

Farrag, Yousof; Sabando, Constanza; Rodríguez-Llamazares, Saddys; Bouza, Rebeca; Rojas, Claudio; Barral, Luís

2018-04-25

A simple method for producing donut-shaped starch microparticles by adding ethanol to a heated aqueous slurry of corn starch is presented. The obtained microparticles were analysed by SEM, XRD and DSC. The average size of microparticles was 14.1 ± 0.3 μm with holes of an average size of 4.6 ± 0.2 μm. The crystalline arrangement of the microparticles was of a V-type single helix. The change in crystallinity from A-type of the starch granules to a more open structure, where water molecules could penetrate easier within the microparticles, substantially increased their solubility and swelling power. The microparticles exhibited a higher gelatinization temperature and a lower gelatinization enthalpy than did the starch granules. The donut-shaped microparticles were stable for more than 18 months and can be used as a carrier of an active compound or as a filler in bioplastics. Copyright © 2017 Elsevier Ltd. All rights reserved.

Transcript expression plasticity as a response to alternative larval host plants in the speciation process of corn and rice strains of Spodoptera frugiperda.

Science.gov (United States)

Silva-Brandão, Karina Lucas; Horikoshi, Renato Jun; Bernardi, Daniel; Omoto, Celso; Figueira, Antonio; Brandão, Marcelo Mendes

2017-10-16

Our main purpose was to evaluate the expression of plastic and evolved genes involved in ecological speciation in the noctuid moth Spodoptera frugiperda, the fall armyworm (FAW); and to demonstrate how host plants might influence lineage differentiation in this polyphagous insect. FAW is an important pest of several crops worldwide, and it is differentiated into host plant-related strains, corn (CS) and rice strains (RS). RNA-Seq and transcriptome characterization were applied to evaluate unbiased genetic expression differences in larvae from the two strains, fed on primary (corn) and alternative (rice) host plants. We consider that genes that are differently regulated by the same FAW strain, as a response to different hosts, are "plastic". Otherwise, differences in gene expression between the two strains fed on the same host are considered constitutive differences. Individual performance parameters (larval and pupal weight) varied among conditions (strains vs. hosts). A total of 3657 contigs was related to plastic response, and 2395 contigs were differentially regulated in the two strains feeding on preferential and alternative hosts (constitutive contigs). Three molecular functions were present in all comparisons, both down- and up-regulated: oxidoreductase activity, metal-ion binding, and hydrolase activity. Metabolization of foreign chemicals is among the key functions involved in the phenotypic variation of FAW strains. From an agricultural perspective, high plasticity in families of detoxifying genes indicates the capacity for a rapid response to control compounds such as insecticides.

Microbial production of hydrogen from starch-manufacturing wastes

Energy Technology Data Exchange (ETDEWEB)

Yokoi, H.; Maki, R.; Hirose, J.; Hayashi, S. [Miyazaki Univ. (Japan). Dept. of Applied Chemistry

2002-05-01

Effective hydrogen production from starch-manufacturing wastes by microorganisms was investigated. Continuous hydrogen production in high yield of 2.7 mol H{sub 2} mol{sup -1} glucose was attained by a mixed culture of Clostridium butyricum and Enterobacter aerogenes HO-39 in the starch waste medium consisting of sweet potato starch residue as a carbon source and corn steep liquor as a nitrogen source in a repeated batch culture. Rhodobacter sp. M-19 could produce hydrogen from the supernatant of the culture broth obtained in the repeated batch culture of C. butyricum and E. aerogenes HO-39. Hydrogen yield of 4.5 mol H{sub 2} mol{sup -1} glucose was obtained by culturing Rhodobacter sp. M-19 in the supernatant supplemented with 20{mu}gl{sup -1} Na{sub 2}MoO{sub 4} 2H{sub 2}O and 10mgl{sup -1} EDTA in a repeated batch culture with pH control at 7.5. Therefore, continuous hydrogen production with total hydrogen yield of 7.2 mol H{sub 2} mol{sup -1} glucose from the starch remaining in the starch residue was attained by the repeated batch culture with C. butyricum and E. aerogenes HO-39 and by the successive repeated batch culture with Rhodobacter sp. M-19. (Author)

Effects of some extrusion variables on physicochemical characteristics of extruded corn starch-passion fruit pulp (Passiflora edulis) snacks.

Science.gov (United States)

Cortés, R Nallely Falfán; Guzmán, Iñigo Verdalet; Martínez-Bustos, Fernando

2014-12-01

The aim of this work was to study the effect of the addition of passion fruit pulp (PFP: 0-7%), the variation of barrel temperature in the third zone extruder (BT: 80-140 °C) and feed moisture (FM:16-30%) in a blend of corn starch and passion fruit pulp on different physicochemical characteristics of directly expanded snacks by extrusion technology. Single-screw laboratory extruder and a central, composite, rotatable experimental design were used. Expansion index of extrudates ranged between 1.0 and 1.8. Decreasing of feed moisture (18%), passion fruit pulp concentration (1.42%) and the increasing of barrel temperature (127 °C) resulted in higher expansion index. The increasing of feed moisture and passion fruit pulp concentration resulted in higher penetration force values of extrudates. The passion fruit pulp concentration showed a highly significant effect (p ≤ 0.01) on the L *, a * and b * parameters. Passion fruit pulp has a reasonable source of β-carotene, proteins and dietary fibers that can be added to expanded snacks.

Evaluation of tensile properties and water absortion of cassava starch film

Science.gov (United States)

Walster, R. Justin; Rozyanty, A. R.; Kahar, A. W. M.; Musa, L.; Shahnaz, S. B. S.

2017-09-01

Casava Starch film was prepared by casting method with different percentage of glycerol (0%, 0.5%, 1.0%, 1.5%, 2.0% and 2.5%) as plasticizer. The effect of glycerol content in starch film on mechanical and water absorption properties was studied. Results shows that the increase of glycerol content in cassava starch film had decrease the tensile strength, tensile modulus and increase the elongation of break properties. The result of water absorbency tended to increase for starch film with higher percentage of glycerol content. The incorporation of glycerol in cassava starch film had increase the water absorption ability due to increase of hydroxyl content contributed by glycerol.

Poly(Lactic Acid) Filled with Cassava Starch-g-Soybean Oil Maleate

OpenAIRE

Kiangkitiwan, Nopparut; Srikulkit, Kawee

2013-01-01

Poly(lactic acid), PLA, is a biodegradable polymer, but its applications are limited by its high cost and relatively poorer properties when compared to petroleum-based plastics. The addition of starch powder into PLA is one of the most promising efforts because starch is an abundant and cheap biopolymer. However, the challenge is the major problem associated with poor interfacial adhesion between the hydrophilic starch granules and the hydrophobic PLA, leading to poorer mechanical properties....

Corrosion protection of steel by thin coatings of starch-oil dry lubricants

Science.gov (United States)

Corrosion of materials is one of the most serious and challenging problems faced worldwide by industry. Dry lubricants reduce friction between two metal surfaces. This research investigated the inhibition of corrosive behavior a dry lubricant formulation consisting of jet-cooked corn starch and soyb...

Variability of electron spin resonance (ESR) signal of γ -irradiated starches

International Nuclear Information System (INIS)

Silva, Gilberto D.; Rodrigues Junior, Orlando; Mastro, Nelida L. del

2017-01-01

Food preservation is one of the practical applications of radiation processing of materials. Starch is an abundant and cheap nutritious biopolymer and also is the material for appropriate food systems and for technical industries. Starch granules are partially crystalline structures composed mainly of two types of starch: amylose, an essentially linear polymer, and amylopectin, with 3-44% of branch points. Electron spin resonance (ESR) spectroscopy is a very powerful and sensitive method for the characterization of the electronic structures of materials with unpaired electrons. The aim of the present work was to monitor the disappearance of the short life and long-life free radicals formed during γ-irradiation of 3 different starches. Corn, potato and fermented cassava starches were irradiated in a "6"0Co source Gammacell 220 with 20 kGy, dose rate around 1 kGy h"-"1. EPR spectra were obtained at room temperature using a Bruker EMX plus model, X band equipment. The main type of ESR signal from irradiated starch is a singlet with a g-value of about 2.0. The fading of ESR signals was followed for 350 hours, and presents differences among the different starch type reflecting differences in molecular arrangements of starch crystalline and amorphous fractions, although ESR spectra seemed to be common for all starches. (author)

Variability of electron spin resonance (ESR) signal of γ -irradiated starches

Energy Technology Data Exchange (ETDEWEB)

Silva, Gilberto D.; Rodrigues Junior, Orlando; Mastro, Nelida L. del, E-mail: nlmastro@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2017-11-01

Food preservation is one of the practical applications of radiation processing of materials. Starch is an abundant and cheap nutritious biopolymer and also is the material for appropriate food systems and for technical industries. Starch granules are partially crystalline structures composed mainly of two types of starch: amylose, an essentially linear polymer, and amylopectin, with 3-44% of branch points. Electron spin resonance (ESR) spectroscopy is a very powerful and sensitive method for the characterization of the electronic structures of materials with unpaired electrons. The aim of the present work was to monitor the disappearance of the short life and long-life free radicals formed during γ-irradiation of 3 different starches. Corn, potato and fermented cassava starches were irradiated in a {sup 60}Co source Gammacell 220 with 20 kGy, dose rate around 1 kGy h{sup -1}. EPR spectra were obtained at room temperature using a Bruker EMX plus model, X band equipment. The main type of ESR signal from irradiated starch is a singlet with a g-value of about 2.0. The fading of ESR signals was followed for 350 hours, and presents differences among the different starch type reflecting differences in molecular arrangements of starch crystalline and amorphous fractions, although ESR spectra seemed to be common for all starches. (author)

Naturally Compatible: Starch Acetate/Cellulosic Fiber Composites. I. Processing and Properties

DEFF Research Database (Denmark)

Nättinen, Kalle; Hyvärinen, Sari; Joffe, Roberts

2010-01-01

Composite compounds based on hemp and flax fibers in triethyl citrate plasticized starch acetate were prepared by melt processing. For better properties and processability, compounds with plasticizer contents in the range 20-35 wt% were screened. Composites were prepared with fiber contents up...... to 50 wt%. The composite mechanical properties were measured from injection molded test specimens. A Young's modulus of 8.3 GPa and stress at maximum load of 51 MPa were obtained with 40 wt% flax fiber in a plasticized starch acetate with 20 wt% triethyl citrate. Decreasing the plasticizer...... and increasing the fiber content, the tensile properties were consistently improved. An almost linear relation between fiber content and the tensile properties was found. The increase of the fiber content first improved the impact strength, but at higher fiber contents resulted in a reduction of impact strength...

Biodegradable aliphatic-aromatic copolyester/corn starch blend composite reinforced with coffee parchment husk

International Nuclear Information System (INIS)

Silva, Valquiria A.; Teixeira, Jaciele G.; Gomes, Michelle G.; Ortiz, Angel V.; Oliveira, Rene R.; Scapin, Marcos A.; Moura, Esperidiana A.B.; Colombo, Maria A.

2013-01-01

In recent years, studies have shown that the addition of natural fiber or proper filler is an effective strategy for achieving improved properties in biodegradable polymer materials. Moreover, is especially important if such fibers are residues of agro-industrial processes. In this work, a promising technique to develop biodegradable polymer matrix composite based on aliphatic-aromatic copolyester/corn starch blend (Evela®) and coffee parchment husk, which is residue from coffee processing is described. The biodegradable polymeric blend (Evela®) with 5 % (w/w) of ball-milled coffee parchment husk fiber powder, with size ≤250 μm, without any modification was prepared by melt-mixing processing, using a twin screw extruder machine and then pelletized. In a second step, the pelletized Evela®)/coffee parchment (Composite) was then dried at 70 ± 2 deg C for 24 h in a circulating air oven, fed into injection molding machine and test specimens were obtained. The Composite specimen samples were irradiated using an electron beam accelerator, at radiation dose of 20 and 40 kGy, at room temperature in presence of air. The irradiated and non-irradiated samples were characterized by means of scanning electron microscopy (SEM), X-Ray diffraction (XRD), tensile tests and sol-gel analysis and the correlation between their properties was discussed. In addition, coffee parchment husk fiber characterization by SEM, EDS, XRD and WDXRF have also been carried out with a view to evaluate its importance in determining the end-use properties of the composite. (author)

Biodegradable aliphatic-aromatic copolyester/corn starch blend composite reinforced with coffee parchment husk

Energy Technology Data Exchange (ETDEWEB)

Silva, Valquiria A.; Teixeira, Jaciele G.; Gomes, Michelle G.; Ortiz, Angel V.; Oliveira, Rene R.; Scapin, Marcos A.; Moura, Esperidiana A.B. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Colombo, Maria A., E-mail: valquiriaalves36@yahoo.com.br [Faculdade de Tecnologia da Zona Leste (FATEC), Sao Paulo, SP (Brazil)

2013-07-01

In recent years, studies have shown that the addition of natural fiber or proper filler is an effective strategy for achieving improved properties in biodegradable polymer materials. Moreover, is especially important if such fibers are residues of agro-industrial processes. In this work, a promising technique to develop biodegradable polymer matrix composite based on aliphatic-aromatic copolyester/corn starch blend (Evela®) and coffee parchment husk, which is residue from coffee processing is described. The biodegradable polymeric blend (Evela®) with 5 % (w/w) of ball-milled coffee parchment husk fiber powder, with size ≤250 μm, without any modification was prepared by melt-mixing processing, using a twin screw extruder machine and then pelletized. In a second step, the pelletized Evela®)/coffee parchment (Composite) was then dried at 70 ± 2 deg C for 24 h in a circulating air oven, fed into injection molding machine and test specimens were obtained. The Composite specimen samples were irradiated using an electron beam accelerator, at radiation dose of 20 and 40 kGy, at room temperature in presence of air. The irradiated and non-irradiated samples were characterized by means of scanning electron microscopy (SEM), X-Ray diffraction (XRD), tensile tests and sol-gel analysis and the correlation between their properties was discussed. In addition, coffee parchment husk fiber characterization by SEM, EDS, XRD and WDXRF have also been carried out with a view to evaluate its importance in determining the end-use properties of the composite. (author)

Studies on the physicochemical properties of Abelmuscus ...

African Journals Online (AJOL)

The ability to absorb water and swell considerably could be explored in disintegration of tablets. Corn starch induced faster onset of plastic deformation than Okra powders but the overall amount of plastic deformation occurring during compression was higher for Okra powders. Therefore tableting machines with longer dwell ...

Investigating the phase transformations in starch during gelatinisation

International Nuclear Information System (INIS)

Tan, I.; Sopade, P.A.; Halley, P.J.

2003-01-01

Full text: Starch, a natural polymer of amylose and amylopectin, continues to be a prime material for biodegradable plastic applications as well as many food and non-food uses. Raw starch exists as semicrystalline granules with complex internal supramolecular packing and can be hierarchically organised on four length scales: molecular scale (∼ Angstroms), lamellar structure (∼90 Angstroms); growth rings (∼ 0.1 μm) and the whole granule morphology (∼μm). Starch can be converted into thermoplastic material (TPS) through destructurisation in the presence of plasticisers under specific extrusion conditions. During the transformation of granular starch into TPS, the complex granular supramolecular structure gives rise to the characteristic endothermic first order transition known as gelatinization. Despite advances in research on starch gelatinisation, the precise structural change and transitions involved are still a matter of debate. Moreover, structural variables such as botanical origins, amylose/amylopectin ratio, macromolecular sizes, etc, have been known to influence the physicochemical properties of starch and the transitions it undergoes.While understanding the linkage between structural characteristics and gelatinisation behaviour will provide fundamental knowledge that is critical for the development of next-generation starch biodegradable plastics, this has proved difficult mainly due to poor knowledge of the exact mechanism involved in gelatinisation. This is further complicated by the sketchy idea on the role of structure and organisation of the starch granule. Studies in our laboratory on four types of maize starches with different amylose/amylopectin ratio revealed that although there is a general trend on the variation of gelatinisation parameters with plasticisers concentration, the extent of the variation are different for different types of starch. It was also found that these differences are not a directly related to the variation in

Effects of alpha-amylase reaction mechanisms on analysis of resistant-starch contents.

Science.gov (United States)

Moore, Samuel A; Ai, Yongfeng; Chang, Fengdan; Jane, Jay-lin

2015-01-22

This study aimed to understand differences in the resistant starch (RS) contents of native and modified starches obtained using two standard methods of RS content analysis: AOAC Method 991.43 and 2002.02. The largest differences were observed in native potato starch, cross-linked wheat distarch phosphate, and high-amylose corn starch stearic-acid complex (RS5) between using AOAC Method 991.43 with Bacillus licheniformis α-amylase (BL) and AOAC Method 2002.02 with porcine pancreatic α-amylase (PPA). To determine possible reasons for these differences, we hydrolyzed raw-starch granules with BL and PPA with equal activity at pH 6.9 and 37°C for up to 84 h and observed the starch granules displayed distinct morphological differences after the hydrolysis. Starches hydrolyzed by BL showed erosion on the surface of the granules; those hydrolyzed by PPA showed pitting on granule surfaces. These results suggested that enzyme reaction mechanisms, including the sizes of the binding sites and the reaction patterns of the two enzymes, contributed to the differences in the RS contents obtained using different methods of RS analysis. Copyright © 2014 Elsevier Ltd. All rights reserved.

Biodegradability and mechanical properties of starch films from Andean crops.

Science.gov (United States)

Torres, F G; Troncoso, O P; Torres, C; Díaz, D A; Amaya, E

2011-05-01

Different Andean crops were used to obtain starches not previously reported in literature as raw material for the production of biodegradable polymers. The twelve starches obtained were used to prepare biodegradable films by casting. Water and glycerol were used as plasticizers. The mechanical properties of the starch based films were assessed by means of tensile tests. Compost tests and FTIR tests were carried out to assess biodegradability of films. The results show that the mechanical properties (UTS, Young's modulus and elongation at break) of starch based films strongly depend on the starch source used for their production. We found that all the starch films prepared biodegrade following a three stage process and that the weight loss rate of all the starch based films tested was higher than the weight loss rate of the cellulose film used as control. Copyright © 2011 Elsevier B.V. All rights reserved.

In situ study starch gelatinization under ultra-high hydrostatic pressure using synchrotron SAXS

KAUST Repository

Yang, Zhi; Gu, Qinfen; Lam, Elisa; Tian, Feng; Chaieb, Saharoui; Hemar, Yacine

2015-01-01

The gelatinization of waxy (very low amylose) corn and potato starches by high hydrostatic pressure (HHP) (up to ∼1 GPa) was investigated in situ using synchrotron small-angle X-ray scattering (SAXS) on samples held in a diamond anvil cell (DAC

Modification of Sorghum Starch-Cellulose Bioplastic with Sorghum Stalks Filler

Directory of Open Access Journals (Sweden)

Yuli Darni

2017-05-01

Full Text Available This study evaluated the feasibility of bioplastics production by various ratio of sorghum starch and cellulose from red seaweed Eucheuma spinossum, and the use of glycerol as plasticizer and sorghum stalks as filler. Solid-liquid matrix transition should be far over the operating temperature of gelatinization and extracted at 95oC in order to avoid the loss of conductivity. The analyzed variables were starch and cellulose seaweed Eucheuma spinossum and the addition of variation of filler. Sorghum stalk could be expected to affect the mechanical and physical properties of bioplastics. A thin sheet of plastic (plastic film was obtained as a result that have been tested mechanically to obtain the best condition for the formulation of starch-cellulose 8.5:1.5 (g/g. From the result of morphological studies, the fillers in the mixture composites were more randomly in each product and the addition of filler can increase mechanical properties of bioplastics. Chemical modification had a major effect on the mechanical properties. The phenomena of degradation and thermoplasticization were visible at chemical changes that can be observed in FTIR spectrum test results.

pH catalyzed pretreatment of corn bran for enhanced enzymatic arabinoxylan degradation

DEFF Research Database (Denmark)

Agger, Jane; Johansen, Katja Salomon; Meyer, Anne S.

2011-01-01

Corn bran is mainly made up of the pericarp of corn kernels and is a byproduct stream resulting from the wet milling step in corn starch processing. Through statistic modeling this study examined the optimization of pretreatment of corn bran for enzymatic hydrolysis. A low pH pretreatment (pH 2......, 150°C, 65min) boosted the enzymatic release of xylose and glucose and maximized biomass solubilization. With more acidic pretreatment followed by enzymatic hydrolysis the total xylose release was maximized (at pH 1.3) reaching ∼50% by weight of the original amount present in destarched corn bran......, but the enzyme catalyzed xylose release was maximal after pretreatment at approx. pH 2. The total glucose release peaked after pretreatment of approx. pH 1.5 with an enzymatic release of approx. 68% by weight of the original amounts present in destarched corn bran. For arabinose the enzymatic release...

Hyperbranched polyester polyol modified with polylactic acid as a compatibilizer for plasticized tapioca starch/polylactic acid blends

Directory of Open Access Journals (Sweden)

Ricardo Mesias

2018-03-01

Full Text Available Abstract A hyperbranched polyester polyol of the second generation (HBP2 was modified with polylactic acid (HBP2-g-PLA and employed as a compatibilizer for plasticized tapioca starch (TPS/polylactic acid (PLA blends. The effect of the compatibilizer HBP2- g-PLA was evaluated in comparison to the control sample (TPS/PLA blend without HBP2-g-PLA. The torque value of the TPS/PLA blends with HBP2- g-PLA was lower than that of the control sample, while thermal stability and crystallinity followed opposite behavior. The glass transition temperature (Tg and degree of crystallinity of the TPS/PLA blends with HBP2-g-PLA decreased with increasing mass fraction of HBP2-g-PLA. By scanning electron microscopy (SEM, it was observed that the morphology of the TPS/PLA blends with HBP2-g -PLA was more homogeneous than that of the control sample, confirming that HBP2- g-PLA acted as a compatibilizer and plasticizing agent to the TPS/PLA blends. Rheological analysis of the compatibilized TPS/PLA blends indicated the presence of microstructure.

CHEMICAL AND ENERGETIC CONTENT OF CORN BEFORE AND AFTER PRE-CLEANING

Directory of Open Access Journals (Sweden)

Sandra Iara Furtado Costa Rodrigues

2015-04-01

Full Text Available The poultry industry normally has little control over the raw material that arrives at the processing plant. This experiment aimed to evaluate chemical and energetic quality of corn obtained in a feed mill before and after pre-cleaning. Twenty samples of 30 kg of corn each were taken from trucks delivering corn to the mill. The trucks were then unloaded and the material passed through a pre-cleaning process when another sample was taken. Samples were graded and physical properties evaluated: density (g/L, grain percentages of foreign material, impurities, fragments, broken, soft, insect damaged, fire-burnt, fermented, damaged, cracked and fine particles, as well as chemical composition analysis: Apparent metabolizable energy for poultry (AME, ether extract (EE, crude fiber (CF, starch (STA, water activity (WA, crude protein (CP, digestible and total lysine, methionine, cystine, threonine, tryptophan, valine, isoleucine, leucine, phenylalanine, histidine and arginine. The experiment was a randomized design with two treatments (before and after pre-cleaning and twenty replications. Data was analyzed using SAS ® and treatment differences obtained using F test. Correlations and principal components were calculated. There was a decrease in density after the pre-cleaning process, which was probably due to the removal of earth and stones rather than grain and its fractions. Significant increases were found for insect damage, fermented and damaged grain while fire-burn was significantly reduced after the pre-cleaning process. Starch increased after pre-cleaning which is a result of contaminants that normally are poor in this carbohydrate, but fiber levels increased too. Apparent metabolizable energy, aminoacids, digestible (P<0.05 and total (P<0.05 histidine, total lysine and methionine (P<0.1 levels were reduced after pre-cleaning. Density was higher when there were fewer impurities such as straw, husk or small grains. Broken corn was positively

Changes in the mechanical properties of thermoplastic potato starch in relation with changes in B-type crystallinity

NARCIS (Netherlands)

Vliegenthart, J.F.G.; Soest, J.J.G. van; Hulleman, S.H.D.; Wit, D. de

1996-01-01

The influence of crystallization on the stress-strain behaviour of thermoplastic potato starch has been monitored. Potato starch has been processed by extrusion with glycerol and water added as plasticizers. The thermoplastic starch consists of a molecular network of semicrystalline amylose and

Influence of the inclusion of cooked cereals and pea starch in diets based on soy or pea protein concentrate on nutrient digestibility and performance of young pigs.

Science.gov (United States)

Parera, N; Lázaro, R P; Serrano, M P; Valencia, D G; Mateos, G G

2010-02-01

An experiment was conducted to compare different dietary vegetable sources of starch and protein on the coefficient of apparent total tract digestibility (CATTD) of energy and nutrients and performance of piglets from 29 to 60 d of age. The experiment was completely randomized with 6 treatments arranged factorially with 3 sources of starch (cooked-flaked corn, cooked-flaked rice, and pea starch) and 2 sources of protein [soy protein concentrate (SPC) and pea protein concentrate (PPC)]. The pea starch and the PPC used were obtained by dehulling and grinding pea seeds to a mean particle size of 30 microm. Each treatment was replicated 6 times (6 pigs per pen). For the entire experiment, piglets fed cooked rice had greater ADG than piglets fed pea starch with piglets fed cooked corn being intermediate (471, 403, and 430 g/d, respectively; P Protein source did not have any effect on piglet performance. The CATTD of DM, OM, and GE were greater (P pea starch being intermediate. Crude protein digestibility was not affected by source of starch but was greater for the diets based on SPC than for diets based on PPC (0.836 vs. 0.821; P Protein source did not affect the digestibility of any of the other dietary components. It is concluded that cooked rice is an energy source of choice in diets for young pigs. The inclusion of PPC in the diet reduced protein digestibility but had no effects on energy digestibility or piglet performance. Therefore, the finely ground starch and protein fractions of peas can be used in substitution of cooked corn or SPC, respectively, in diets for young pigs.

ENZYMATIC DETERMINATION OF STARCH IN DOCE DE LEITE USING DIALYSIS

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DEMIATE Ivo Motim

2001-01-01

Full Text Available The importance of starch for the food industry makes it necessary to develop new, fast, economic and accurate methodologies for its quantification. In the present paper starch hydrolysis using commercial enzymes of industrial grade are studied aiming to develop an easy and cheap analysis, available to a greater number of industries and technicians. The proposed method is simple, divided in a first step where soluble sugars are eliminated from the samples by using dialysis, followed by starch hydrolysis of the retained fraction with a thermoresistent bacterial alfa-amylase (Termamyl 120L® and an amyloglucosidase (AMG 300L®. The hydrolysis conditions were those suggested by the enzyme producer. After the hydrolysis step the material was dialysed again for the extraction of glucose that was quantified by the glucose-oxidase colorimetric reactant. The results allowed the construction of calibration equations for starch determination on the analyzed samples. These samples were produced on a laboratory scale and native and acid-modified corn starches were added in known concentrations. By considering the final dilutions employed for glucose determination on the samples, it was possible to confirm that they were identical to that of the glucose-oxidase reactant calibration.

Thermal and mechanical properties of fatty acid starch esters.

Science.gov (United States)

Winkler, H; Vorwerg, W; Rihm, R

2014-02-15

The current study examined thermal and mechanical properties of fatty acid starch esters (FASEs). All highly soluble esters were obtained by the sustainable, homogeneous transesterification of fatty acid vinyl esters in dimethylsulfoxide (DMSO). Casted films of products with a degree of substitution (DS) of 1.40-1.73 were compared with highly substituted ones (DS 2.20-2.63). All films were free of any plasticizer additives. Hydrophobic surfaces were characterized by contact angle measurements. Dynamic scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA) revealed thermal transitions (T(g), T(m)) which were influenced by the internal plasticizing effect of the ester groups. Thermal gravimetric analysis (TGA) measurements showed the increased thermal stability toward native starch. Tensile tests revealed the decreasing strength and stiffness of the products with increasing ester-group chain length while the elongation increased up to the ester group laurate and after that decreased. Esters of the longest fatty acids, palmitate and stearate turned out to be brittle materials due to super molecular structures of the ester chains such as confirmed by X-ray. Summarized products with a DS 1.40-1.73 featured more "starch-like" properties with tensile strength up to outstanding 43 MPa, while products with a DS >2 behaved more "oil-like". Both classes of esters should be tested as a serious alternative to commercial starch blends and petrol-based plastics. The term Cnumber is attributed to the number of total C-Atoms of the fatty acid (e.g. C6=Hexanoate). Copyright © 2013 Elsevier Ltd. All rights reserved.

Rheological and gelation properties of rice starch modified with 4-alpha-glucanotransferase.

Science.gov (United States)

Lee, Kwang Yeon; Kim, Yong-Ro; Park, Kwan Hwa; Lee, Hyeon Gyu

2008-04-01

Rheological measurements were performed to characterize rice starch modified with 4-alpha-glucanotransferase (4alphaGTase) isolated from Thermus scotoductus, in terms of effects of the enzyme and starch concentration on flow behavior, gel strength, and melting and gelling kinetics of the modified rice starch. Consistency index decreased and flow behavior index increased with the level of enzyme treatment, and at high level of enzyme treatment, it demonstrated Bingham plastic behavior. As the level of enzyme decreased and the starch concentration increased, gelation time decreased and the final gel strength increased significantly. Regardless of treatment variables, all the modified starch gels melted at similar temperature.

Material properties and glass transition temperatures of different thermoplastic starches after extrusion processing

NARCIS (Netherlands)

Janssen, Léon P.B.M.; Karman, Andre P.; Graaf, Robbert A. de

Four different starch sources, namely waxy maize, wheat, potato and pea starch were extruded with the plasticizer glycerol, the latter in concentrations of 15, 20 and 25% (w/w). The glass transition temperatures of the resulting thermoplastic products were measured by Dynamic Mechanical Thermal

Application of oxidized starch in bake-only chicken nuggets.

Science.gov (United States)

Purcell, Sarah; Wang, Ya-Jane; Seo, Han-Seok

2014-05-01

There is a need to reduce the fat content in fried foods because of increasing health concerns from consumers. Oxidized starches have been utilized in many coating applications for their adhesion ability. However, it is not known if they perform similarly in bake-only products. This study investigated the application of oxidized starch in bake-only chicken nuggets. Oxidized starches were prepared from 7 starches and analyzed for gelatinization and pasting properties. Chicken nuggets were prepared using batter containing wheat flour, oxidized starch, salt, and leavening agents prior to steaming, oven baking, freezing, and final oven baking for sensory evaluation. All nuggets were analyzed for hardness by a textural analyzer, crispness by an acoustic sound, and sensory characteristics by a trained panel. The oxidation level used in the study did not alter the gelatinization temperature of most starches, but increased the peak pasting viscosity of both types of corn and rice starches and decreased that of tapioca and potato starches. There were slight differences in peak force and acoustic reading between some treatments; however, the differences were not consistent with starch type or amylose content. There was no difference among the treatments as well as between the control with wheat flour and the treatments partially replaced with oxidized starches in all sensory attributes of bake-only nuggets evaluated by the trained panel. There is a need to reduce the fat content in fried food, such as chicken nuggets, because of increasing childhood obesity. Oxidized starches are widely used in coating applications for their adhesion ability. This study investigated the source of oxidized starches in steam-baked coated nuggets for their textural and sensorial properties. The findings from this research will provide an understanding of the contributions of starch source and oxidation to the texture and sensory attributes of bake-only nuggets, and future directions to improve

Rheological behavior of gamma-irradiated cassava (Manihot esculenta crantz) starch

Energy Technology Data Exchange (ETDEWEB)

Silva, Orelio L.; Uehara, Vanessa B.; Mastro, Nelida L. del, E-mail: nlmastro@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2013-07-01

Cassava starch is the by-product of the process of pressing water out of cassava to make cassava meal. The juice has a fine starch, similar to rice or potato starch that, when dried, yields polvilho doce (sweet manioc starch); from the fermented juice comes polvilho azedo (sour manioc starch). Cassava starch can perform most of the functions where maize, rice and wheat starch are currently used. The aim of the present work was to determine the influence or ionizing radiation on the rheological behavior of aqueous preparations of gamma-irradiated cassava starch at different concentrations. Samples of polvilho doce and polvilho azedo were obtained at the local market and irradiated in plastic bags in a Gammacell 220 with doses of 1, 3 e 5 kGy, dose rate ∼ 1.2 kGy h-1. A Brooksfield viscometer was employed for the viscosity measurements. The results showed a strong dependence of the viscosity with the concentration of the starch solutions. In most of the cases there was a decrease of viscosity with the increase of the radiation dose usually seen in irradiated polysaccharides. Nevertheless, the dose response relation of the two kind of starch was different. (author)

Rheological behavior of gamma-irradiated cassava (Manihot esculenta crantz) starch

International Nuclear Information System (INIS)

Silva, Orelio L.; Uehara, Vanessa B.; Mastro, Nelida L. del

2013-01-01

Cassava starch is the by-product of the process of pressing water out of cassava to make cassava meal. The juice has a fine starch, similar to rice or potato starch that, when dried, yields polvilho doce (sweet manioc starch); from the fermented juice comes polvilho azedo (sour manioc starch). Cassava starch can perform most of the functions where maize, rice and wheat starch are currently used. The aim of the present work was to determine the influence or ionizing radiation on the rheological behavior of aqueous preparations of gamma-irradiated cassava starch at different concentrations. Samples of polvilho doce and polvilho azedo were obtained at the local market and irradiated in plastic bags in a Gammacell 220 with doses of 1, 3 e 5 kGy, dose rate ∼ 1.2 kGy h-1. A Brooksfield viscometer was employed for the viscosity measurements. The results showed a strong dependence of the viscosity with the concentration of the starch solutions. In most of the cases there was a decrease of viscosity with the increase of the radiation dose usually seen in irradiated polysaccharides. Nevertheless, the dose response relation of the two kind of starch was different. (author)

Overcoming hydrolysis of raw corn starch under industrial conditions with Bacillus licheniformis ATCC 9945a α-amylase.

Science.gov (United States)

Šokarda Slavić, Marinela; Pešić, Milja; Vujčić, Zoran; Božić, Nataša

2016-03-01

α-Amylase from Bacillus licheniformis ATCC 9945a (BliAmy) was proven to be very efficient in hydrolysis of granular starch below the temperature of gelatinization. By applying two-stage feeding strategy to achieve high-cell-density cultivation of Escherichia coli and extracellular production of BliAmy, total of 250.5 U/mL (i.e. 0.7 g/L) of enzyme was obtained. Thermostability of amylase was exploited to simplify purification. The hydrolysis of concentrated raw starch was optimized using response surface methodology. Regardless of raw starch concentration tested (20, 25, 30 %), BliAmy was very effective, achieving the final hydrolysis degree of 91 % for the hydrolysis of 30 % starch suspension after 24 h. The major A-type crystalline structure and amorphous domains of the starch granule were degraded at the same rates, while amylose-lipid complexes were not degraded. BliAmy presents interesting performances on highly concentrated solid starch and could be of value for starch-consuming industries while response surface methodology (RSM) could be efficiently applied for the optimization of the hydrolysis.

The role of Aspergillus flavus veA in the production of extracellular proteins during growth on starch substrates.

Science.gov (United States)

Duran, Rocio M; Gregersen, Scott; Smith, Timothy D; Bhetariya, Preetida J; Cary, Jeffrey W; Harris-Coward, Pamela Y; Mattison, Christopher P; Grimm, Casey; Calvo, Ana M

2014-06-01

The aflatoxin-producer and opportunistic plant pathogenic, filamentous fungus Aspergillus flavus is responsible for the contamination of corn and other important agricultural commodities. In order to obtain nutrients from the host A. flavus produces a variety of extracellular hydrolytic enzymes. Interestingly, A. flavus amylase and protease activity are dependent on the global regulator veA, a gene known to regulate morphogenesis and secondary metabolism in numerous fungi. Analysis of starch degradation by fungal enzymes secreted into broths of starch- or corn kernel-based media showed a notable accumulation of glucose in samples of the A. flavus control strain while the deletion veA sample accumulated high levels of maltose and maltotriose and only a small amount of glucose. Furthermore, SDS-PAGE and proteomics analysis of culture broths from starch- or corn kernel-based media demonstrated differential production of a number of proteins that included a reduction in the amount of a glucoamylase protein in the veA mutant compared to the control strain, while an alpha-amylase was produced in greater quantities in the veA mutant. Quantitative real-time PCR and western blot analyses using anti-glucoamylase or alpha-amylase antisera supported the proteomics results. Additionally, an overall reduction in protease activity was observed in the veA mutant including production of the alkaline protease, oryzin, compared to the control strain. These findings contribute to our knowledge of mechanisms controlling production of hydrolases and other extracellular proteins during growth of A. flavus on natural starch-based substrates.

Starch and cellulose nanocrystals together into thermoplastic starch bionanocomposites.

Science.gov (United States)

González, Kizkitza; Retegi, Aloña; González, Alba; Eceiza, Arantxa; Gabilondo, Nagore

2015-03-06

In the present work, thermoplastic maize starch based bionanocomposites were prepared as transparent films, plasticized with 35% of glycerol and reinforced with both waxy starch (WSNC) and cellulose nanocrystals (CNC), previously extracted by acidic hydrolysis. The influence of the nanofiller content was evaluated at 1 wt.%, 2.5 wt.% and 5 wt.% of WSNC. The effect of adding the two different nanoparticles at 1 wt.% was also investigated. As determined by tensile measurements, mechanical properties were improved at any composition of WSNC. Water vapour permeance values maintained constant, whereas barrier properties to oxygen reduced in a 70%, indicating the effectiveness of hydrogen bonding at the interphase. The use of CNC or CNC and WSNC upgraded mechanical results, but no significant differences in barrier properties were obtained. A homogeneous distribution of the nanofillers was demonstrated by atomic force microscopy, and a shift of the two relaxation peaks to higher temperatures was detected by dynamic mechanical analysis. Copyright © 2014 Elsevier Ltd. All rights reserved.

An evaluation of cassava, sweet potato and field corn as potential carbohydrate sources for bioethanol production in Alabama and Maryland

Energy Technology Data Exchange (ETDEWEB)

Ziska, Lewis H.; Tomecek, Martha; Sicher, Richard [United States Department of Agriculture, Agricultural Research Service, Crop Systems and Global Change Lab, 10300 Baltimore Avenue, Building 1, Beltsville, MD 20705 (United States); Runion, G. Brett; Prior, Stephen A.; Torbet, H. Allen [United States Department of Agriculture, Agricultural Research Service, National Soil Dynamics Laboratory, 411 South Donahue Drive, Auburn, AL 36832 (United States)

2009-11-15

The recent emphasis on corn production to meet the increasing demand for bioethanol has resulted in trepidation regarding the sustainability of the global food supply. To assess the potential of alternative crops as sources of bioethanol production, we grew sweet potato (Ipomoea batatas) and cassava (Manihot esculentum) at locations near Auburn, Alabama and Beltsville, Maryland in order to measure root carbohydrate (starch, sucrose, glucose) and root biomass. Averaged for both locations, sweet potato yielded the highest concentration of root carbohydrate (ca 80%), primarily in the form of starch (ca 50%) and sucrose (ca 30%); whereas cassava had root carbohydrate concentrations of (ca 55%), almost entirely as starch. For sweet potato, overall carbohydrate production was 9.4 and 12.7 Mg ha{sup -1} for the Alabama and Maryland sites, respectively. For cassava, carbohydrate production in Maryland was poor, yielding only 2.9 Mg ha{sup -1}. However, in Alabama, carbohydrate production from cassava averaged {proportional_to}10 Mg ha{sup -1}. Relative to carbohydrate production from corn in each location, sweet potato and cassava yielded approximately 1.5 x and 1.6 x as much carbohydrate as corn in Alabama; 2.3 x and 0.5 x for the Maryland site. If economical harvesting and processing techniques could be developed, these data suggest that sweet potato in Maryland, and sweet potato and cassava in Alabama, have greater potential as ethanol sources than existing corn systems, and as such, could be used to replace or offset corn as a source of biofuels. (author)

Sensory evaluation of aromatic foods packed in developed starch based films using fuzzy logic

Directory of Open Access Journals (Sweden)

Tanima Chowdhury

2015-04-01

Full Text Available The last two decades have seen attempts to replace non biodegradable, synthetic food packaging films with alternatives made from biopolymers. The objective of the present work was to evaluate sensory quality of tea leaf and culinary tastemaker powder when sealed in pouches based on starch films.Films were developed from corn starch and a functional polysaccharide (FP from amylose (AM, methylcellulose (MC, and hydroxypropylmethylcellulose (HPMC, using a casting technique. Pouches were stored inside a secondary package (plastic jar under ambient condition for 90 days. Sensory attributes of the stored food samples were evaluated (tea in liquor form and the scores analysed by fuzzy logic. Results were compared with similarly stored foods but using market available poly-pouches as packaging material.For tea and tastemaker in general, the relative importance of the sensory attributes under consideration was assessed as:  aroma (Highly important >taste (Highly important>colour (Highly important > strength (Important for tea, and taste (Highly important>aroma (Highly important>colour (Important>appearance (Important for tastemaker. Among the three films that were developed, the highly important sensory attributes of aroma and taste were maintained as ‘Very good’ when the foods were packed in starch–HPMC/AM film. When the products were packed in market-available poly-pouches they exhibited similar attributes. With the exception of ‘Very good’ maintenance of the colour of tastemaker by the commercial pouch, irrespective of film and food, the colour and strength/appearance were retained in the ‘Good’-‘Satisfactory’ range. The overall sensory score of tea was also maintained as ‘Very good’ in starch-HPMC film.

Physicochemical properties of cassava starch and starch-keratin prepared biofilm

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Oluwasina Olugbenga Oladayo

2016-08-01

Full Text Available Synthetic plastics pose one of the biggest threats to the environment and a promising solution is biodegradable polymers. This study investigates the properties of biofilms prepared using starch/keratin blend with and without formaldehyde. Some starch properties in percentage are; moisture content 0.27, hydration capacity 189.66, amylopectin content 65.79 and amylose content 34.21. From the water testing results, thickness swelling, water absorption capacity and linear expansion of biofilm without formaldehyde after 10 s of soaking in water were 28.59%, 8.89% and 4.90% respectively and 65.30%, 91.33% and 46.29% respectively after 40 s. But, higher values are recorded for those biofilms made with addition of formaldehyde. Thus using water effect on the properties of the biofilms as the performance index, the research indicates that biofilms without formaldehyde had better performance than those with formaldehyde

Biodegradable packaging materials conception based on starch and polylactic acid (PLA) reinforced with cellulose.

Science.gov (United States)

Masmoudi, Fatma; Bessadok, Atef; Dammak, Mohamed; Jaziri, Mohamed; Ammar, Emna

2016-10-01

The plastic materials used for packaging are increasing leading to a considerable amount of undegradable solid wastes. This work deals with the reduction of conventional plastics waste and the natural resources preservation by using cellulosic polymers from renewable resources (alfa and luffa). Plasticized starch films syntheses were achieved at a laboratory scale. These natural films showed some very attractive mechanical properties at relatively low plasticizers levels (12 to 17 % by weight). Furthermore, mixtures including polylactic acid polymer (PLA) and cellulose fibers extracted from alfa and luffa were investigated by melt extrusion technique. When used at a rate of 10 %, these fibers improved the mixture mechanical properties. Both developed materials were biodegradable, but the plasticized starch exhibited a faster biodegradation kinetic compared to the PLA/cellulose fibers. These new materials would contribute to a sustainable development and a waste reduction.

Compositional profile and variation of Distillers Dried Grains with Solubles from various origins with focus on non-starch polysaccharides

DEFF Research Database (Denmark)

Pedersen, Mads Brøgger; Dalsgaard, S.; Knudsen, Knud Erik Bach

2014-01-01

nutrients (e.g. protein, fat, fibre and minerals) after fermentation of starch to ethanol. Corn DDGS differentiated from wheat DDGS by a greater content of fat (P≤0.006), insoluble-NSP (Pcellulose (P=0.032), and arabinose/xylose (P....001). Wheat DDGS differentiated from corn DDGS by a greater content of ash (P=0.001), soluble-NSP (Plignin (P...Corn-, wheat- and mixed cereal Distillers' Dried Grains with Solubles (DDGS) were investigated for compositional variability among DDGS origins, ethanol plants, and the relationship between corn and corresponding DDGS. A total of 138 DDGS samples were analyzed by use of Near Infrared Reflectance...

Effects of Gamma Irradiation on Mechanical Properties of LDPE/Cassava Starch Blends

International Nuclear Information System (INIS)

Hemvichian, Kasinee; Suwanmala, Phiriyatorn; Kangsumrith, Wararat

2007-08-01

Full text: Low density polyethylene (LDPE) was blended with cassava starch. The starch content was varied from 10, 20 to 30%. The blends were compression molded to form plastic sheets. The sheets were cut into dog bone-shaped specimens. The samples were gamma irradiated in air with the total dose of 10, 20, 50 and 100 kGy. The mechanical properties of both the unirradiated and irradiated samples were characterized using a Universal Testing Machine. The results demonstrated that tensile strength of the LDPE/Starch blends increased with dose, while it simultaneously decreased with starch content

Fundamental Study on the Impact of Gluten-Free Starches on the Quality of Gluten-Free Model Breads

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Stefan W. Horstmann

2016-04-01

Full Text Available Starch is widely used as an ingredient and significantly contributes to texture, appearance, and overall acceptability of cereal based foods, playing an important role due to its ability to form a matrix, entrapping air bubbles. A detailed characterisation of five gluten-free starches (corn, wheat, rice, tapioca, potato was performed in this study. In addition, the influence of these starches, with different compositional and morphological properties, was evaluated on a simple gluten-free model bread system. The morphological characterisation, evaluated using scanning electron microscopy, revealed some similarities among the starches, which could be linked to the baking performance of the breads. Moreover, the lipid content, though representing one of the minor components in starch, was found to have an influence on pasting, bread making, and staling. Quality differences in cereal root and tuber starch based breads were observed. However, under the baking conditions used, gluten-free rendered wheat starch performed best, followed by potato starch, in terms of loaf volume and cell structure. Tapioca starch and rice starch based breads were not further analysed, due to an inferior baking performance. This is the first study to evaluate gluten-free starch on a simple model bread system.

Effect of carboxymethyl cellulose concentration on physical properties of biodegradable cassava starch-based films

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Sriburi Pensiri

2011-02-01

Full Text Available Abstract Background Cassava starch, the economically important agricultural commodity in Thailand, can readily be cast into films. However, the cassava starch film is brittle and weak, leading to inadequate mechanical properties. The properties of starch film can be improved by adding plasticizers and blending with the other biopolymers. Results Cassava starch (5%w/v based films plasticized with glycerol (30 g/100 g starch were characterized with respect to the effect of carboxymethyl cellulose (CMC concentrations (0, 10, 20, 30 and 40%w/w total solid and relative humidity (34 and 54%RH on the mechanical properties of the films. Additionally, intermolecular interactions were determined by Fourier transform infrared spectroscopy (FT-IR, melting temperature by differential scanning calorimetry (DSC, and morphology by scanning electron microscopy (SEM. Water solubility of the films was also determined. Increasing concentration of CMC increased tensile strength, reduced elongation at break, and decreased water solubility of the blended films. FT-IR spectra indicated intermolecular interactions between cassava starch and CMC in blended films by shifting of carboxyl (C = O and OH groups. DSC thermograms and SEM micrographs confirmed homogeneity of cassava starch-CMC films. Conclusion The addition of CMC to the cassava starch films increased tensile strength and reduced elongation at break of the blended films. This was ascribed to the good interaction between cassava starch and CMC. Cassava starch-CMC composite films have the potential to replace conventional packaging, and the films developed in this work are suggested to be suitable for low moisture food and pharmaceutical products.

Characterization of edible films of Swartzia burchelli phosphated starches and development of coatings for post-harvest application to cherry tomatoes

Directory of Open Access Journals (Sweden)

Millene Aparecida Gomes

2016-08-01

Full Text Available The market demand for corn starch and cassava continues to increase because of their use in edible applications, their biodegradable nature, and other appealing properties. As a result, there is a need to identify alternative starch sources, for example, the seeds of S. burchelli, with the potential to be modified for use in post-harvest applications. Therefore, this study aimed to develop and characterize edible films based on the starch phosphates of the seeds of S. burchelli, with the specific aim to apply these starches to cherry tomatoes for post-harvest conservation. After extraction, the starch was phosphorylated with sodium tripolyphosphate (STP in different concentrations and times according to a 2 x 2 factorial design with additional treatment (native starch. After modification, the starch phosphates were selected for the preparation of edible films using glycerol as a plasticizer, in proportions of 5, 10, 15 and 20% for each selected starch. The films were measured for thickness, permeability to water vapor and solubility in water. According to their permeability values, 4 films were selected for application in the coverage of cherry tomatoes. The conservation of cherry tomatoes with and without coverage was studied over 8 evaluation times (up to 21 days at 10±2 °C and 80±5% relative humidity. The weight loss, soluble solids, titratable acidity, maturation index, and firmness were measured every 3 days during storage. The starch phosphates showed a phosphorus content within that established by standards, such that the resulting films are acceptable for use in food for human consumption. The edible films presented with an acceptable appearance and without the development of cracks. The concentration of glycerol and the type of starch influenced the characteristics of the films, increasing the permeability and reducing the water solubility of the various edible films. The best result obtained regarding the conservation of cherry

Dietary sucrose and starch affect dysplastic characteristics in carcinogen-induced aberrant crypt foci in rat colon.

Science.gov (United States)

Caderni, G; Lancioni, L; Luceri, C; Giannini, A; Lodovici, M; Biggeri, A; Dolara, P

1997-03-19

To study whether dietary carbohydrates affect dysplasia in aberrant crypt foci (ACF), rats treated with 1,2-dimethilhydrazine (DMH) were fed for three months with diets containing 46% sucrose or corn starch. The number of ACF/colon in the two dietary groups was similar (P = 0.58), but ACF were smaller in the starch than in sucrose group (P colon carcinogenesis while sucrose in the diet is detrimental, promoting the dysplasia of preneoplastic lesions like ACF.

Wet method for measuring starch gelatinization temperature using electrical conductivity.

Science.gov (United States)

Morales-Sanchez, E; Figueroa, J D C; Gaytan-Martínez, M

2009-09-01

The objective of the present study was to develop a method for obtaining the gelatinization temperature of starches by using electrical conductivity. Native starches from corn, rice, potato, and wheat were prepared with different proportions of water and heated from room temperature to 90 degrees C, in a device especially designed for monitoring the electrical conductivity as a function of temperature. The results showed a linear trend of the electrical conductivity with the temperature until it reaches the onset gelatinization temperature. After that point, the electrical conductivity presented an increment or decrement depending on the water content in the sample and it was related to starch swelling and gelatinization phenomena. At the end gelatinization temperature, the conductivity becomes stable and linear, indicating that there are no more changes of phase. The starch gelatinization parameter, which was evaluated in the 4 types of starches using the electrical conductivity, was compared with those obtained by using differential scanning calorimeter (DSC). The onset temperature at which the electrical conductivity increased or decreased was found to be similar to that obtained by DSC. Also, the final temperature at which the electrical conductivity returned to linearity matched the end gelatinization temperature of the DSC. Further, a wet method for measuring the onset, peak, and end gelatinization temperatures as a function of temperature using the electrical conductivity curves is presented for a starch-water suspension.

Starch-zein beldns formed by shear flow

NARCIS (Netherlands)

Habeych Narvaez, E.A.; Dekkers, B.; Goot, van der A.J.; Boom, R.M.

2008-01-01

A newly in-house developed shearing device was used to explore the formation of new types of microstructures in concentrated starch¿zein blends. The device allowed processing of the biopolymer blends under homogeneous, simple shear flow conditions. Water and glycerol were added as plasticizers.

Real-time monitoring of high-gravity corn mash fermentation using in situ raman spectroscopy.

Science.gov (United States)

Gray, Steven R; Peretti, Steven W; Lamb, H Henry

2013-06-01

In situ Raman spectroscopy was employed for real-time monitoring of simultaneous saccharification and fermentation (SSF) of corn mash by an industrial strain of Saccharomyces cerevisiae. An accurate univariate calibration model for ethanol was developed based on the very strong 883 cm(-1) C-C stretching band. Multivariate partial least squares (PLS) calibration models for total starch, dextrins, maltotriose, maltose, glucose, and ethanol were developed using data from eight batch fermentations and validated using predictions for a separate batch. The starch, ethanol, and dextrins models showed significant prediction improvement when the calibration data were divided into separate high- and low-concentration sets. Collinearity between the ethanol and starch models was avoided by excluding regions containing strong ethanol peaks from the starch model and, conversely, excluding regions containing strong saccharide peaks from the ethanol model. The two-set calibration models for starch (R(2)  = 0.998, percent error = 2.5%) and ethanol (R(2)  = 0.999, percent error = 2.1%) provide more accurate predictions than any previously published spectroscopic models. Glucose, maltose, and maltotriose are modeled to accuracy comparable to previous work on less complex fermentation processes. Our results demonstrate that Raman spectroscopy is capable of real time in situ monitoring of a complex industrial biomass fermentation. To our knowledge, this is the first PLS-based chemometric modeling of corn mash fermentation under typical industrial conditions, and the first Raman-based monitoring of a fermentation process with glucose, oligosaccharides and polysaccharides present. Copyright © 2013 Wiley Periodicals, Inc.

Extrusion induced low-order starch matrices: Enzymic hydrolysis and structure.

Science.gov (United States)

Zhang, Bin; Dhital, Sushil; Flanagan, Bernadine M; Luckman, Paul; Halley, Peter J; Gidley, Michael J

2015-12-10

Waxy, normal and highwaymen maize starches were extruded with water as sole plasticizer to achieve low-order starch matrices. Of the three starches, we found that only high-amylose extrudate showed lower digestion rate/extent than starches cooked in excess water. The ordered structure of high-amylose starches in cooked and extruded forms was similar, as judged by NMR, XRD and DSC techniques, but enzyme resistance was much greater for extruded forms. Size exclusion chromatography suggested that longer chains were involved in enzyme resistance. We propose that the local molecular density of packing of amylose chains can control the digestion kinetics rather than just crystallinity, with the principle being that density sufficient to either prevent/limit binding and/or slow down catalysis can be achieved by dense amorphous packing. Copyright © 2015 Elsevier Ltd. All rights reserved.

Thermal Characterization of Modified Tacca Leontopetaloides Starch and Natural Rubber Based Thermoplastic Elastomer

International Nuclear Information System (INIS)

Ainatul Mardhiah Mohd Amin; Nur Shahidah Ab Aziz; Nurul Shuhada Mohd Makhtar; Miradatul Najwa Mohd Rodhi; Suhaila Mohd Sauid

2014-01-01

The purpose of this study is to identify the potential of Tacca leontopetaloides starch as bio-based thermoplastic elastomers, TPEs. Starch based polymer had been recognized to have highly potential in replace existing source of conventional elastomeric polymer. The modification process of blending starch with natural rubber, plasticizers, additives, and filler contribute to the enhancement and improvement for the properties of starch in order to produce biopolymers by approaching the properties of TPEs. Thermal properties of starch based thermoplastic was studied to evaluate the decomposition and degradation of the samples by using Thermogravimetric Analysis, TGA while the properties of endothermic reactions of the samples were thermally analyzed via Differential Scanning Calorimetry, DSC. From the analysis, it was found that the thermal properties of samples were revealed by recognizing GM-2 (green materials, GM) has high thermal resistance towards high temperature up to 480.06 degree Celsius with higher amount of residue which is 4.97 mg compared to other samples. This indicates GM-2 comprises of superior combination of ratio between natural rubbers and glycerol (plasticizer) in purpose of approaching the properties of Thermoplastic Elastomers, TPEs. (author)

Floatability of Fe-bearing silicates in the presence of starch: Adsorption and spectroscopic studies

International Nuclear Information System (INIS)

Severov, V V; Filippova, I V; Filippov, L O

2013-01-01

Natural polysaccharides such as starch, dextrin, cellulose and their derivatives are promising non-toxic and biodegradable organic flocculants and flotation depressants. This paper presents the investigation of mechanism of adsorption of corn starch on quartz and Fe-bearing amphibole, i.e. pargasite. The direct measurement of starch adsorption on the mineral surfaces shows no difference between quartz and pargasite. However, the starch adsorption on the magnetite is more important. FT-IR spectroscopy studies reports different adsorption mechanism of starch on quartz and pargasite surface. The key changes observed in starch absorption on quartz are the major shifts in C-0 stretching frequencies presumed existence of a hydrogen bond between starch and quartz surface. The similar changes were observed in this region of IR-band for pargasite. The appearance and disappearance of the bands in the region 960-920 cm −1 corresponds probably to formation of a new chemical bond between starch O-H groups and metal atoms on pargasite surface with formation of a surface complex. This result confirms that adsorption of the starch on the pargasite surface is droved by two mechanism. Hence, existence of strong chemical bond between starch and pargasite surface explains decrease of its floatability compared to quartz in process of iron ore flotation and forces to search new conditioning reagent modes.

Floatability of Fe-bearing silicates in the presence of starch: Adsorption and spectroscopic studies

Science.gov (United States)

Severov, V. V.; Filippova, I. V.; Filippov, L. O.

2013-03-01

Natural polysaccharides such as starch, dextrin, cellulose and their derivatives are promising non-toxic and biodegradable organic flocculants and flotation depressants. This paper presents the investigation of mechanism of adsorption of corn starch on quartz and Fe-bearing amphibole, i.e. pargasite. The direct measurement of starch adsorption on the mineral surfaces shows no difference between quartz and pargasite. However, the starch adsorption on the magnetite is more important. FT-IR spectroscopy studies reports different adsorption mechanism of starch on quartz and pargasite surface. The key changes observed in starch absorption on quartz are the major shifts in C-0 stretching frequencies presumed existence of a hydrogen bond between starch and quartz surface. The similar changes were observed in this region of IR-band for pargasite. The appearance and disappearance of the bands in the region 960-920 cm-1 corresponds probably to formation of a new chemical bond between starch O-H groups and metal atoms on pargasite surface with formation of a surface complex. This result confirms that adsorption of the starch on the pargasite surface is droved by two mechanism. Hence, existence of strong chemical bond between starch and pargasite surface explains decrease of its floatability compared to quartz in process of iron ore flotation and forces to search new conditioning reagent modes.

Wheat B-starch based polymeric materials

Czech Academy of Sciences Publication Activity Database

Kotek, Jiří; Kruliš, Zdeněk; Šárka, E.

2011-01-01

Roč. 105, č. 9 (2011), s. 731 ISSN 0009-2770. [International Conference on Polysaccharides-Glycoscience /7./. 02.11.2011-04.11.2011, Prague] R&D Projects: GA ČR GA525/09/0607 Institutional research plan: CEZ:AV0Z40500505 Keywords : biodegradable plastic * polycaprolactone * B- starch Subject RIV: JI - Composite Materials

Thermal Behavior of Tacca leontopetaloides Starch-Based Biopolymer

Directory of Open Access Journals (Sweden)

Nurul Shuhada Mohd Makhtar

2013-01-01

Full Text Available Starch is used whenever there is a need for natural elastic properties combined with low cost of production. However, the hydrophilic properties in structural starch will decrease the thermal performance of formulated starch polymer. Therefore, the effect of glycerol, palm olein, and crude palm oil (CPO, as plasticizers, on the thermal behavior of Tacca leontopetaloides starch incorporated with natural rubber in biopolymer production was investigated in this paper. Four different formulations were performed and represented by TPE1, TPE2, TPE3, and TPE4. The compositions were produced by using two-roll mill compounding. The sheets obtained were cut into small sizes prior to thermal testing. The addition of glycerol shows higher enthalpy of diffusion in which made the material easily can be degraded, leaving to an amount of 6.6% of residue. Blending of CPO with starch (TPE3 had a higher thermal resistance towards high temperature up to 310°C and the thermal behavior of TPE2 only gave a moderate performance compared with other TPEs.

Thermal, Mechanical and Water Resistance Properties of LDPE/Starch Bio-Based Polymer Blends for Food Packing Applications

OpenAIRE

Berber Yamak, Hale

2016-01-01

In this study, low density polyethylene, LDPE was melt blended with starch using twin screw extruder to form biodegradable polymer blends. The LDPE/starch blend films used in food packing were obtained by hot pressing of the granules produced by extrusion process. The starch content was varied from 0 to 40 wt% of LDPE. To provide fine starch dispersion, glycerol and zinc stearate were used as plasticizer and compatibilizer, respectively. The effect of starch content on the properties of LDPE ...

Use of MMT and MMT organoclay in production of starch nanocomposites

International Nuclear Information System (INIS)

Schlemmer, D.; Sales, M.J.A.; Macedo, J.L. de; Angelica, R.S.

2010-01-01

Starch can be used to replace petrochemical plastics for short shelf life. However, starch films have poor mechanical strength and sensitivity to moisture. This can be improved through the incorporation of nanoclays, such as montmorillonite, forming nanocomposites. Nanocomposites were prepared with 1, 3, 5 and 10% of montmorillonite, using pequi oil as plasticizer. The clay was also modified with a quaternary ammonium salt. The clays were characterized by XRF, XRD, IR and TG. Results confirmed the organophilization. The nanocomposites diffractograms showed that the addition of small amounts of clay produces delaminated nanocomposites. Already the addition of larger amount of clay does not form nanocomposites, or leads to the formation of intercalated nanocomposites. (author)

Exogenous lactobacilli mitigate microbial changes associated with grain fermentation (corn, oats, and wheat) by equine fecal microflora ex vivo.

Science.gov (United States)

Harlow, Brittany E; Lawrence, Laurie M; Harris, Patricia A; Aiken, Glen E; Flythe, Michael D

2017-01-01

Cereal grains are often included in equine diets. When starch intake exceeds foregut digestion starch will reach the hindgut, impacting microbial ecology. Probiotics (e.g., lactobacilli) are reported to mitigate GI dysbioses in other species. This study was conducted to determine the effect of exogenous lactobacilli on pH and the growth of amylolytic and lactate-utilizing bacteria. Feces were collected from 3 mature geldings fed grass hay with access to pasture. Fecal microbes were harvested by differential centrifugation, washed, and re-suspended in anaerobic media containing ground corn, wheat, or oats at 1.6% (w/v) starch and one of five treatments: Control (substrate only), L. acidophilus, L. buchneri, L. reuteri, or an equal mixture of all three (107 cells/mL, final concentration). After 24 h of incubation (37°C, 160 rpm), samples were collected for pH and enumerations of total amylolytics, Group D Gram-positive cocci (GPC; Enterococci, Streptococci), lactobacilli, and lactate-utilizing bacteria. Enumeration data were log transformed prior to ANOVA (SAS, v. 9.3). Lactobacilli inhibited pH decline in corn and wheat fermentations (P Exogenous lactobacilli decreased amylolytics, while increasing lactate-utilizers in corn and wheat fermentations (P Exogenous lactobacilli decreased the initial (first 8 h) rate of starch catalysis when wheat was the substrate, but did not decrease total (24 h) starch utilization in any case. These results indicate that exogenous lactobacilli can impact the microbial community and pH of cereal grain fermentations by equine fecal microflora ex vivo. Additionally, dead (autoclaved) exogenous lactobacilli had similar effects as live lactobacilli on fermentation. This latter result indicates that the mechanism by which lactobacilli impact other amylolytic bacteria is not simple resource competition.

Nuclearmagnetic resonance investigations to the character of the waterbinding for the structure of the native starch corn

International Nuclear Information System (INIS)

Hennig, H.J.

1976-01-01

The signals of the proton and deuteron magnetic resonance from water molecules sorbed on native starch contain a splitting, caused from water molecules in ordered regions. This splitting could not be maintained from retrogradated crystalline amylose. The water molecules are ordered more uniform in potato starch then in wheat starch, which is related to the difference in the crystalline structures. The proton resonance of potato starch contains two further components from water molecules in amorphous regions and on the ions respectively. From the deuteron resonance and their dependence on temperature first insights were obtained into the processes occuring by simutaneous treatment with heat and moisture. (orig.) [de

Establishing whether the structural feature controlling the mechanical properties of starch films is molecular or crystalline.

Science.gov (United States)

Li, Ming; Xie, Fengwei; Hasjim, Jovin; Witt, Torsten; Halley, Peter J; Gilbert, Robert G

2015-03-06

The effects of molecular and crystalline structures on the tensile mechanical properties of thermoplastic starch (TPS) films from waxy, normal, and high-amylose maize were investigated. Starch structural variations were obtained through extrusion and hydrothermal treatment (HTT). The molecular and crystalline structures were characterized using size-exclusion chromatography and X-ray diffractometry, respectively. TPS from high-amylose maize showed higher elongation at break and tensile strength than those from normal maize and waxy maize starches when processed with 40% plasticizer. Within the same amylose content, the mechanical properties were not affected by amylopectin molecular size or the crystallinity of TPS prior to HTT. This lack of correlation between the molecular size, crystallinity and mechanical properties may be due to the dominant effect of the plasticizer on the mechanical properties. Further crystallization of normal maize TPS by HTT increased the tensile strength and Young's modulus, while decreasing the elongation at break. The results suggest that the crystallinity from the remaining ungelatinized starch granules has less significant effect on the mechanical properties than that resulting from starch recrystallization, possibly due to a stronger network from leached-out amylose surrounding the remaining starch granules. Copyright © 2014 Elsevier Ltd. All rights reserved.

Preparation and characterization of starch-based loose-fill packaging foams

Science.gov (United States)

Fang, Qi

Regular and waxy corn starches were blended in various ratios with biodegradable polymers including polylactic acid (PLA), Eastar Bio Copolyester 14766 (EBC) and Mater-Bi ZF03U (MBI) and extruded with a C. W. Brabender laboratory twin screw extruder using a 3-mm die nozzle at 150°C and 150 rev/min. Physical characteristics including radial expansion, unit density and bulk density and water solubility index, water absorption characteristics, mechanical properties including compressibility, Young's modulus, spring index, bulk compressibility and bulk spring index and abrasion resistance were investigated as affected by the ingredient formulations, i.e. type of polymers, type of starches, polymer to starch ratio and starch moisture content. A completely randomized factorial blocking experimental design was used. Fifty-four treatments resulted. Each treatment was replicated three times. SAS statistical software package was used to analyze the data. Foams made of waxy starch had better radial expansion, lower unit density and bulk density than did foams made of regular starch. Regular starch foams had significantly lower water solubility index than did the waxy starch foams. PLA-starch foams had the lowest compressibility and Young's modulus. MBI-starch foams were the most rigid. All foams had excellent spring indices and bulk spring indices which were comparable to the spring index of commercial expanded polystyrene foam. Correlations were established between the foam mechanical properties and the physical characteristics. Foam compressibility and Young's modulus decreased as increases in radial expansion and decreases in unit and bulk densities. Their relationships were modeled with power law equations. No correlation was observed between spring index and bulk spring index and foam physical characteristics. MBI-starch foams had the highest equilibrium moisture content. EBC-starch and PLA-starch foams had similar water absorption characteristics. No significant

Effects of cyclodextrin glycosiltransferase modified starch and cyclodextrins on plasma glucose and lipids metabolism in mice

Science.gov (United States)

The potential functional and nutritional benefits of granular starch treated with cyclodextrin glycosyltransferase (CGTase) and the released cyclodextrins (CDs) were explored in in vivo studies. The metabolic effects of diets in the C57BL/6J mouse containing native and enzymatically modified corn st...

Thermo-mechanical behaviors of thermoplastic starch derived from sugar palm tree (Arenga pinnata).

Science.gov (United States)

Sahari, J; Sapuan, S M; Zainudin, E S; Maleque, M A

2013-02-15

In recent years, increasing environmental concerns focused greater attention on the development of biodegradable materials. A thermoplastic starch derived from bioresources, sugar palm tree was successfully developed in the presence of biodegradable glycerol as a plasticizer. Sugar palm starch (SPS) was added with 15-40 w/w% of glycerol to prepare workable bioplastics and coded as SPS/G15, SPS/G20, SPS/G30 and SPS/G40. The samples were characterized for thermal properties, mechanical properties and moisture absorption on exposure to humidity were evaluated. Morphological studies through scanning electron microscopy (SEM) were used to explain the observed mechanical properties. Generally, the addition of glycerol decrease the transition temperature of plasticized SPS. The mechanical properties of plasticized SPS increase with the increasing of glycerol but up to 30 w/w%. Meanwhile, the water absorption of plasticized SPS decrease with increasing of glycerol. Copyright © 2012 Elsevier Ltd. All rights reserved.

Granular starch hydrolysis for fuel ethanol production

Science.gov (United States)

Wang, Ping

addition were evaluated in the dry grind process using GSHE (GSH process). Addition of proteases resulted in higher ethanol concentrations (15.2 to 18.0% v/v) and lower (DDGS) yields (32.9 to 45.8% db) compared to the control (no protease addition). As level of proteases and GSHE increased, ethanol concentrations increased and DDGS yields decreased. Proteases addition reduced required GSHE dose. Ethanol concentrations with protease addition alone were higher than with urea or with addition of both protease and urea. Corn endosperm consists of soft and hard endosperm. More exposed starch granules and rough surfaces produced from soft endosperm compared to hard endosperm will create more surface area which will benefit the solid phase hydrolysis as used in GSH process. In this study, the effects of protease, urea, endosperm hardness and GSHE levels on the GSH process were evaluated. Soft and hard endosperm materials were obtained by grinding and sifting flaking grits from dry milling pilot plant. Soft endosperm resulted in higher ethanol concentrations (at 72 hr) compared to ground corn or hard endosperm. Addition of urea increased ethanol concentrations (at 72 hr) for soft and hard endosperm. The effect of protease addition on increasing ethanol concentrations and fermentation rates was more predominant for soft endosperm, less for hard endosperm and least for ground corn. The GSH process with protease resulted in higher ethanol concentration than that with urea. For fermentation of soft endosperm, GSHE dose can be reduced. Ground corn fermented faster at the beginning than hard and soft endosperm due to the presence of inherent nutrients which enhanced yeast growth.

Apparent interfacial shear strength of short-flax-fiber/starch acetate composites

DEFF Research Database (Denmark)

Andersons, J.; Modniks, J.; Joffe, R.

2016-01-01

The paper deals with an indirect industry-friendly method for identification of the interfacial shear strength (IFSS) in a fully bio-based composite. The IFSS of flax fiber/starch acetate is evaluated by a modified Bowyer and Bader method based on an analysis of the stress-strain curve of a short......-fiber-reinforced composite in tension. A shear lag model is developed for the tensile stress-strain response of short-fiber-reinforced composites allowing for an elastic-perfectly plastic stress transfer. Composites with different fiber volume fractions and a variable content of plasticizer have been analyzed. The apparent...... IFSS of flax/starch acetate is within the range of 5.5-20.5 MPa, depending on composition of the material. The IFSS is found to be greater for composites with a higher fiber loading and to decrease with increasing content of plasticizer. The IFSS is equal or greater than the yield strength of the neat...

Development of non-water soluble, ductile mung bean starch based edible film with oxygen barrier and heat sealability.

Science.gov (United States)

Rompothi, Onjira; Pradipasena, Pasawadee; Tananuwong, Kanitha; Somwangthanaroj, Anongnat; Janjarasskul, Theeranun

2017-02-10

This research determined the effects of starch concentration (3.5-5.0%w/w), and plasticizer [glycerol (0-30%w/w) or sorbitol (0-60%w/w)] on properties of mung bean starch (MBS) films. The result showed that increasing plasticizer concentration tended to decrease tensile strength (TS), elastic modulus (EM) and oxygen permeability (OP); but increase elongation (%E), solubility, water vapor permeability (WVP) and seal strength. The extent of those changes also depended on starch concentration. Glycerol provided better plasticizer efficiency than sorbitol. A bimodal melting endotherm of retrograded structure was evident in non-plasticized film. However, only a low temperature endotherm was observed in polyol-plasticized films, indicating a plasticizer-induced structural modification. The developed ductile MBS films, (TS of 7.14±0.95 to 46.30±3.09MPa, %E of 2.46±0.21 to 56.95±4.34% and EM of 16.29±3.40 to 1428.45±148.72MPa) with an OP of 0.2397±0.0365 to 1.1520±0.1782 ccmm/m 2 daykPa and seal strength up to 422.36±7.93N/m, demonstrated in this study indicate the potential for food packaging applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

Poly(Lactic Acid) Filled with Cassava Starch-g-Soybean Oil Maleate

Science.gov (United States)

Kiangkitiwan, Nopparut; Srikulkit, Kawee

2013-01-01

Poly(lactic acid), PLA, is a biodegradable polymer, but its applications are limited by its high cost and relatively poorer properties when compared to petroleum-based plastics. The addition of starch powder into PLA is one of the most promising efforts because starch is an abundant and cheap biopolymer. However, the challenge is the major problem associated with poor interfacial adhesion between the hydrophilic starch granules and the hydrophobic PLA, leading to poorer mechanical properties. In this paper, soybean oil maleate (SOMA) was synthesized by grafting soybean oil with various weight percents of maleic anhydride (MA) using dicumyl peroxide (DCP) as an initiator. Then, SOMA was employed for the surface modifying of cassava starch powder, resulting in SOMA-g-STARCH. The obtained SOMA-g-STARCH was mixed with PLA in various weight ratios using twin-screw extruder, resulting in PLA/SOMA-g-STARCH. Finally, the obtained PLA/SOMA-g-STARCH composites were prepared by a compression molding machines. The compatibility, thermal properties, morphology properties, and mechanical properties were characterized and evaluated. The results showed that the compatibility, surface appearance, and mechanical properties at 90 : 10 and 80 : 20 ratios of PLA/SOMA-g-STARCH were the best. PMID:24307883

Modified Starch-Chitosan Edible Films: Physicochemical and Mechanical Characterization

Directory of Open Access Journals (Sweden)

Monserrat Escamilla-García

2017-12-01

Full Text Available Starch and chitosan are widely used for preparation of edible films that are of great interest in food preservation. This work was aimed to analyze the relationship between structural and physical properties of edible films based on a mixture of chitosan and modified starches. In addition, films were tested for antimicrobial activity against Listeria innocua. Films were prepared by the casting method using chitosan (CT, waxy (WS, oxidized (OS and acetylated (AS corn starches and their mixtures. The CT-starches films showed improved barrier and mechanical properties as compared with those made from individual components, CT-OS film presented the lowest thickness (74 ± 7 µm, water content (11.53% ± 0.85%, w/w, solubility (26.77% ± 1.40%, w/v and water vapor permeability ((1.18 ± 0.48 × 10−9 g·s−1·m−1·Pa−1. This film showed low hardness (2.30 ± 0.19 MPa, low surface roughness (Rq = 3.20 ± 0.41 nm and was the most elastic (Young’s modulus = 0.11 ± 0.06 GPa. In addition, films made from CT-starches mixtures reduced CT antimicrobial activity against L. innocua, depending on the type of modified starch. This was attributed to interactions between acetyl groups of AS with the carbonyl and amino groups of CT, leaving CT with less positive charge. Interaction of the pyranose ring of OS with CT led to increased OH groups that upon interaction with amino groups, decreased the positive charge of CT, and this effect is responsible for the reduced antimicrobial activity. It was found that the type of starch modification influenced interactions with chitosan, leading to different films properties.

Nanostructural morphology of plasticized wheat gluten and modified potato starch composites: relationship to mechanical and barrier properties.

Science.gov (United States)

Muneer, Faraz; Andersson, Mariette; Koch, Kristine; Menzel, Carolin; Hedenqvist, Mikael S; Gällstedt, Mikael; Plivelic, Tomás S; Kuktaite, Ramune

2015-03-09

In the present study, we were able to produce composites of wheat gluten (WG) protein and a novel genetically modified potato starch (MPS) with attractive mechanical and gas barrier properties using extrusion. Characterization of the MPS revealed an altered chain length distribution of the amylopectin fraction and slightly increased amylose content compared to wild type potato starch. WG and MPS of different ratios plasticized with either glycerol or glycerol and water were extruded at 110 and 130 °C. The nanomorphology of the composites showed the MPS having semicrystalline structure of a characteristic lamellar arrangement with an approximately 100 Å period observed by small-angle X-ray scattering and a B-type crystal structure observed by wide-angle X-ray scattering analysis. WG has a structure resembling the hexagonal macromolecular arrangement as reported previously in WG films. A larger amount of β-sheets was observed in the samples 70/30 and 30/70 WG-MPS processed at 130 °C with 45% glycerol. Highly polymerized WG protein was found in the samples processed at 130 °C versus 110 °C. Also, greater amounts of WG protein in the blend resulted in greater extensibility (110 °C) and a decrease in both E-modulus and maximum stress at 110 and 130 °C, respectively. Under ambient conditions the WG-MPS composite (70/30) with 45% glycerol showed excellent gas barrier properties to be further explored in multilayer film packaging applications.

Relationship between population growth of the red flour beetle Tribolium castaneum and protein and carbohydrate content in flour and starch.

Science.gov (United States)

Wong, Nellie; Lee, Chow-Yang

2011-12-01

The effects of eight diets (atta flour, wheat flour, self-rising flour, rice flour, custard powder, corn flour, tapioca starch, and potato starch) on the development of the red flour beetle, Tribolium castaneum (Herbst), reared at 29-31 degrees C and 66-70% RH were assessed. Five pairs of male and female T. castaneum were reared on the respective diets for 28 d before the experimental setup was dismantled and adult counts were recorded. In another experiment, the insects were allowed to mate and oviposit in each flour or starch type over a period of 7 d before being removed. The counting of pupae and adult emergence began on the day of emergence and was continued on a daily basis until day 140. Proximate analysis was performed for chemical composition of each diet, and the numbers of new adults that developed were found to be positively correlated (r2 = 0.97; P flour > wheat flour > self-rising flour > rice flour > custard powder > corn flour > tapioca starch > potato starch. T. castaneum larval development to the pupal and adult stages developed significantly faster in atta flour (P flour. Fewer adults emerged from wheat flour, self-rising flour, and rice flour, and no new emergences were recorded for the remaining diets. Developmental rate was much slower in beetles reared on diets in which a low number in progeny was produced. These data illustrate that different diets can influence the sustainability of these insects and affect their development and growth.

Performance, nutritional behavior, and metabolic responses of calves supplemented with forage depend on starch fermentability.

Science.gov (United States)

Mojahedi, S; Khorvash, M; Ghorbani, G R; Ghasemi, E; Mirzaei, M; Hashemzadeh-Cigari, F

2018-05-16

This study evaluated the interactive effects of forage provision on performance, nutritional behavior, apparent digestibility, rumen fermentation, and blood metabolites of dairy calves when corn grains with different fermentability were used. Sixty 3-d-old Holstein calves were randomly assigned to 1 of 4 treatments in a 2 × 2 factorial arrangement. Dietary treatments were (1) steam-flaked (SF) corn without alfalfa hay (AH) supplementation (SF-NO), (2) SF corn with AH supplementation (SF-AH), (3) cracked (CR) corn without AH supplementation (CR-NO), and (4) CR corn with AH supplementation (CR-AH). All calves received the same amount of pasteurized whole milk and weaned on d 56 of the experiment; the study was terminated on d 70. Steam-flaked corn contained higher amounts of gelatinized starch in comparison with cracked corn (44.1 vs. 12.5% of total starch, respectively). Starter intake was not affected by corn processing methods or AH provision during the pre- or postweaning periods. However, we noted an interaction between corn processing methods and forage supplementation for starter intake during d 31 to 50 of the experiment, where calves fed on SF-AH starter had greater starter intake than those fed SF-NO starter, but the starter intake was not different between CR-NO and CR-AH fed calves. Furthermore, AH increased average daily gain (ADG) of calves fed an SF-based diet but not in calves fed a CR-based diet during the preweaning and overall periods. Interaction between forage provision and time was significant for ADG and feed efficiency, as calves supplemented with forage had higher ADG (0.982 vs. 0.592, respectively) and feed efficiency compared with forage unsupplemented calves at the weaning week. Forage supplementation resulted in more stable ruminal condition compared with nonforage-fed calves, as evidenced by higher ruminal pH (5.71 vs. 5.29, respectively) at postweaning and lower non-nutritive oral behavior around weaning time (55 vs. 70.5 min

Irradiated gelatin-potato starch blends: evaluation of physicochemical properties

International Nuclear Information System (INIS)

Inamura, Patricia Y.; Regis, Wellington; Mastro, Nelida L.

2015-01-01

Macromolecular polysaccharides of large chains as starch can interlace with gelatin modifying their mechanical resistance. In this work, biodegradable bovine gelatin-potato starch blends films were developed using glycerol as plasticizer. Three formulations of gelatin/starch proportions (w/w) were used (1:0; 3:1; 1:1) and casting was the chosen method. The dried samples were then submitted to ionizing radiation coming from an electron beam (EB) accelerator with doses of 20 and 40 kGy, at room temperature, in the presence of air. Mechanical properties such as puncture strength and elongation at break were measured. Color measurements, water absorption, moisture, and film solubility were assessed. The results showed that starch addition to films based on gelatin as well as irradiation affected physical and structural properties of the films. Although the increase of starch content in the mixture led to decrease of the puncture force even in samples irradiated with the higher dose, there was a decrease of water absorption of films with the increase of the dose, and also by the higher starch content. Samples irradiated at 20 kGy presented higher moisture and film solubility. The methodology developed in this paper can be applied to other composite systems to establish the best protein:starch ratio, and the contribution of the radiation crosslinking in each specific case. (author)

Irradiated gelatin-potato starch blends: evaluation of physicochemical properties

Energy Technology Data Exchange (ETDEWEB)

Inamura, Patricia Y.; Regis, Wellington; Mastro, Nelida L., E-mail: nlmastro@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2015-07-01

Macromolecular polysaccharides of large chains as starch can interlace with gelatin modifying their mechanical resistance. In this work, biodegradable bovine gelatin-potato starch blends films were developed using glycerol as plasticizer. Three formulations of gelatin/starch proportions (w/w) were used (1:0; 3:1; 1:1) and casting was the chosen method. The dried samples were then submitted to ionizing radiation coming from an electron beam (EB) accelerator with doses of 20 and 40 kGy, at room temperature, in the presence of air. Mechanical properties such as puncture strength and elongation at break were measured. Color measurements, water absorption, moisture, and film solubility were assessed. The results showed that starch addition to films based on gelatin as well as irradiation affected physical and structural properties of the films. Although the increase of starch content in the mixture led to decrease of the puncture force even in samples irradiated with the higher dose, there was a decrease of water absorption of films with the increase of the dose, and also by the higher starch content. Samples irradiated at 20 kGy presented higher moisture and film solubility. The methodology developed in this paper can be applied to other composite systems to establish the best protein:starch ratio, and the contribution of the radiation crosslinking in each specific case. (author)

Production of bioethanol from corn meal hydrolyzates

Energy Technology Data Exchange (ETDEWEB)

Ljiljana Mojovic; Svetlana Nikolic; Marica Rakin; Maja Vukasinovic [University of Belgrade, Belgrade (Serbia and Montenegro). Faculty of Technology and Metallurgy, Department of Biochemical Engineering and Biotechnology

2006-09-15

The two-step enzymatic hydrolysis of corn meal by commercially available {alpha}-amylase and glucoamylase and further ethanol fermentation of the obtained hydrolyzates by Saccharomyces cerevisiae yeast was studied. The conditions of starch hydrolysis such as substrate and enzyme concentration and the time required for enzymatic action were optimized taking into account both the effects of hydrolysis and ethanol fermentation. The corn meal hydrolyzates obtained were good substrates for ethanol fermentation by S. cerevisiae. The yield of ethanol of more than 80% (w/w) of the theoretical was achieved with a satisfactory volumetric productivity P (g/l h). No shortage of fermentable sugars was observed during simultaneous hydrolysis and fermentation. In this process, the savings in energy by carrying out the saccharification step at lower temperature (32{sup o}C) could be realized, as well as a reduction of the process time for 4 h. 31 refs., 5 figs., 2 tabs.

Study of the influence of ZnO addition on the properties of chitosan-banana starch bioplastics

Science.gov (United States)

Sapei, L.; Padmawijaya, K. S.; Sijayanti, O.; Wardhana, P. J.

2017-07-01

Plastics have been widely used in our daily life due to their relatively low cost and practical uses. However, plastics are hardly degraded and thus creating lots of environmental problems. Bioplastics have been developed in order to replace the conventional plastics since they are easily degraded and environmentally friendly. In this research, chitosan-banana starch bioplastics were made with the ratio of 70:30 in the presence of 30% glycerol as the plasticizer. ZnO with varying concentrations of 1, 3, and 5% were added into the biopolymer mixtures before casting in order to improve their mechanical properties. It turned out that 3% ZnO significantly increased the bioplastics tensile strength up to ~36MPa. Vice versa, elongation and swelling percentage were decreased as ZnO concentrations increased. Bioplastics prepared with 3% ZnO were degraded within relatively short time in 90 min. These chitosan-banana starch bioplastics reinforced by ZnO seems quite promising to substitute some commercial conventional plastics.

Examination of injection moulded thermoplastic maize starch

Directory of Open Access Journals (Sweden)

2007-12-01

Full Text Available This paper focuses on the effect of the different injection moulding parameters and storing methods on injection moulded thermoplastic maize starch (TPS. The glycerol and water plasticized starch was processed in a twin screw extruder and then with an injection moulding machine to produce TPS dumbbell specimens. Different injection moulding set-ups and storing conditions were used to analyse the effects on the properties of thermoplastic starch. Investigated parameters were injection moulding pressure, holding pressure, and for the storage: storage at 50% relative humidity, and under ambient conditions. After processing the mechanical and shrinkage properties of the manufactured TPS were determined as a function of the ageing time. While conditioning, the characteristics of the TPS changed from a soft material to a rigid material. Although this main behaviour remained, the different injection moulding parameters changed the characteristics of TPS. Scanning electron microscope observations revealed the changes in the material on ageing.

Optimization of polyhydroxybutyrate production by Bacillus sp. CFR 256 with corn steep liquor as a nitrogen source.

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Vijayendra, S V N; Rastogi, N K; Shamala, T R; Anil Kumar, P K; Kshama, L; Joshi, G J

2007-06-01

Polyhydroxyalkanotes (PHAs), the eco-friendly biopolymers produced by many bacteria, are gaining importance in curtailing the environmental pollution by replacing the non-biodegradable plastics derived from petroleum. The present study was carried out to economize the polyhydroxybutyrate (PHB) production by optimizing the fermentation medium using corn steep liquor (CSL), a by-product of starch processing industry, as a cheap nitrogen source, by Bacillus sp. CFR 256. Response surface methodology (RSM) was used to optimize the fermentation medium using the variables such as corn steep liquor (5-25 g l(-1)), Na(2)HPO(4) 2H(2)O (2.2-6.2 g l(-1)), KH(2)PO(4) (0.5-2.5 g l(-1)), sucrose (5-55 g l(-1)) and inoculum concentration (1-25 ml l(-1)). Central composite rotatable design (CCRD) experiments were carried out to study the complex interactions of the variables.The optimum conditions for maximum PHB production were (g l(-1)): CSL-25, Na(2)HPO(4) 2H(2)O-2.2, KH(2)PO(4) - 0.5, sucrose - 55 and inoculum - 10 (ml l(-1)). After 72 h of fermentation, the amount of PHA produced was 8.20 g l(-1) (51.20% of dry cell biomass). It is the first report on optimization of fermentation medium using CSL as a nitrogen source, for PHB production by Bacillus sp.

Preparation and Characterization of Some Polyethylene Modified- Starch Biodegradable Films

International Nuclear Information System (INIS)

Badrana, A.S.; Ramadanb, A.M.; Ibrahim, N.A.; Kahild, T.; Hussienc, H.A.

2005-01-01

Blends of LDPE with soluble starch, wheat flour and commercial starch were prepared by mixing starch (or flour) with styrene then blending the mixture with LDPE, The starch percents vary between 5 and 50% of the total weight. Their physical and mechanical properties were recorded and compared with pure LDPE. It was observed that the increase in starch or wheat flour contents of the mixture was reversibly proportional to the tensile strength and % elongation. Samples were tested for water absorption. All of the samples were insoluble in cold and boiling water. Moisture uptake increased with immersion time and increasing starch content. The changes in the tensile strength of LDPE/starch (or wheat flour) after the course of thermal oxidation was measured. These results show negligible changes in the tensile strength of the control sample as compared to that of the samples containing the additives. Oxidation processes take advantage of the high temperatures (40-50 degree C) and the time. It was also observed that after 10 weeks of soil burial, the mechanical properties of the films decrease, mainly, due to starch removal from the films. Also, for the weight loss a drastic decrease was observed after 10 weeks of soil burial thereafter it preceded slowly. The LDPE/ starch strips showed weight loss after treating with a-amylase this due to hydrolysis and leaching of the starch. The rate of starch hydrolysis increases with the increase in starch content of the sample. The influence of addition of starch on the overall migration of these films, with different food simulant, was studied, at different temperatures (-4 degree. 25 degree and 40 degree C). All values were significantly lower than the upper limit for overall migration set by the EU (10 mg/dirf) for food grade plastics packaging materials

EVALUATION OF TWO VARIETIES OF SORGHUM FOR STARCH EXTRACTION

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Leyanis Rodríguez Rodríguez

2015-01-01

Full Text Available In Cuba, the wet milling process for the extraction of starch is made from corn, cereal which is currently imported, that is why it is required to substitute it for another grain of national production as it is the case of sorghum. Given the similarities of the two grains in their starch content and considering the potential of sorghum for the food industry, it is developed in this work an assessment process, taking into account two sorghum varieties: red (CIAPR-132 and white (UDG-110. In this sense, a factorial design of the type 2k-1 is made, where the independent variables of most influence in the laboratory process are considered, such as: (x1 type of sorghum, (x2 soaking time and (x3 solution concentration. It is considered that there is no interaction between them and it is taken as the response variable the starch yield in the extraction process. We conclude that the type of sorghum and soaking time are the most influential variables, obtaining the best results for white sorghum subjected for 48 hours to soak in a solution of SO2 at a concentration of 1800 ppm.

Preparation and characterization of starch grafted with toluene poly (propylene oxide diisocyanate

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D.C. Dragunski

2001-01-01

Full Text Available Amylopectin-rich starch samples (Amidex 4001 Corn Products Brasil Ingredientes Industriais Ltda. were grafted with polyethers with the purpose of obtaining new materials for application as solid polymeric electrolytes. Grafting reaction was performed by the addition of starch dissolved in DMSO to toluene poly(propylene oxide diisocyanate (Resibras dissolved in the same solvent. This reaction produced a film with good mechanical properties. The film samples were characterized by 13C-NMR, FTIR, DSC, X-Ray and SEM. The FTIR spectrum shows a sharp NH band and a very small urethane band. The 13C-NMR spectrum revealed a peak at 20 ppm, that can be attributed to the CH3 of the polyether chain, and two small peaks at 117 and 140 ppm, attributed to the aromatic ring. The X-ray diffractograms also indicated that after the grafting reaction, the samples of amylopectin-rich starch are more amorphous. Moreover, the glass transition temperature (Tg dropped from 50 °C to -11 °C. These results indicate formation of grafted products and the low Tg of the samples suggests that polyether-grafted starch is a good candidate to obtain solid polymeric electrolytes.

Starch derivative-based superabsorbent with integration of water-retaining and controlled-release fertilizers.

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Zhong, Kang; Lin, Zuan-Tao; Zheng, Xi-Liang; Jiang, Gang-Biao; Fang, Yu-Sheng; Mao, Xiao-Yun; Liao, Zong-Wen

2013-02-15

Phosphate rock (PHR), a traditional fertilizer, is abundant, but is hard to be utilized by plants. To improve the utilization of PHR, and to integrate water-retaining and controlled-release fertilizers, an agricultural superabsorbent polymer based on sulfonated corn starch/poly (acrylic acid) embedding phosphate rock (SCS/PAA/PHR) was prepared. PHR can be suspended and well-dispersed in SCS/PAA by sulfonated corn starch (SCS). PHR and KOH were mixed in acrylic acid solution to provide phosphorus (P) and potassium (K) nutrients, respectively. Impacts on water absorption capacity of the superabsorbent were investigated. The maximum swelling capacity in distilled water or 0.9 wt.% (weight percent) NaCl solution reached 498 g g(-1) and 65 g g(-1) (water/prepared dry superabsorbent) respectively. Moreover, release behaviours of P and K in SCS/PAA/PHR were also investigated. The results showed that SCS/PAA/PHR possessed excellent sustained-release property of plant nutrient, and the SCS/PAA could improve the P release greatly. Besides, the XPS analysis was employed to study the relationship between PHR and superabsorbent polymer. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effect of gamma irradiation on thermophysical properties of plasticized starch and starch surfactant films

International Nuclear Information System (INIS)

Cieśla, Krystyna; Watzeels, Nick; Rahier, Hubert

2014-01-01

In this work the influence of gamma irradiation on the thermomechanical properties of the films formed in potato starch–glycerol and potato starch–glycerol–surfactant systems were examined by Dynamic Mechanical Analysis, DMA, and Differential Scanning Calorimetry, DSC, and the results were correlated to the amount of the volatile fraction in the films. The starch was irradiated with a dose of 30 kGy. The films were prepared by casting from solutions with addition of 0, 20 and 30 wt% of glycerol. Two endotherms attributed to glass transitions were observed in water or glycerol plasticised samples, the first one shifting to higher temperature after irradiation. A similar shift was observed after irradiation of films prepared from starch–sodium laurate and starch–sodium palmitate systems, while a decrease in glass transition temperature was observed in the case of starch–cetyltrimethylammonium bromide films. Small differences in the content of the volatile fraction reached after the appropriate conditioning had no impact on the direction of temperature shift of Tg observed after irradiation. - Highlights: • The films were prepared basing starch, surfactant and glycerol. • Two glass transitions were observed showing an existence of two phase system. • The first Tg of the starch–CTAB films shifts after irradiation to lower temperature. • In all the other cases it shifts after irradiation to higher temperature. • Differences in volatile fractions content are not important for the temperature shift

Effect of ensiling process of total mixed ration on fermentation profile, nutrient loss and in situ ruminal degradation characteristics of diet.

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Miyaji, Makoto; Matsuyama, Hiroki; Nonaka, Kazuhisa

2017-01-01

This experiment aimed to determine the changes in chemical composition, fermentation profile, in situ disappearance characteristics, and nutrient losses of ensiled total mixed ration (TMR) containing steam-flaked corn or brown rice (BR) during storage. TMRs for dairy cows, containing either steam-flaked corn or BR at 31.9% with 15.2% rye silage, 40.5% alfalfa silage, 5.0% beet pulp and 7.0% soybean meal, were prepared (dry matter (DM) basis). Each TMR was placed in a plastic drum silo, stored at 23°C in an air-conditioned room and sampled 0, 7, 14, 30, 90 and 210 days after preparation. In both grain sources, the fermentation products increased, while DM and starch storage losses increased and starch content greatly decreased during storage. The rapidly degradable fraction and effective ruminal degradability of DM, crude protein and starch increased during storage. These changes of dietary characteristics were large during 30 days of storage, but small after 90 days of storage. Replacing corn with BR led to increased fermentation products, starch loss and effective ruminal degradability of the ensiled TMR. These results indicate that the ensiling process of TMR changes the dietary characteristics and replacing corn with BR in TMR had a large impact on these dietary characteristics. © 2016 Japanese Society of Animal Science.

β-Glucans and Resistant Starch Alter the Fermentation of Recalcitrant Fibers in Growing Pigs.

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Sonja de Vries

Full Text Available Interactions among dietary ingredients are often assumed non-existent when evaluating the nutritive value and health effects of dietary fiber. Specific fibers can distinctly affect digestive processes; therefore, digestibility and fermentability of the complete diet may depend on fiber types present. This study aimed to evaluate the effects of readily fermentable fibers (β-glucans and resistant starch on the degradation of feed ingredients containing more persistent, recalcitrant, fibers. Six semi-synthetic diets with recalcitrant fibers from rapeseed meal (pectic polysaccharides, xyloglucans, and cellulose or corn distillers dried grain with solubles (DDGS; (glucuronoarabinoxylans and cellulose with or without inclusion of β-glucans (6% or retrograded tapioca (40% substituted for corn starch were formulated. Six ileal-cannulated pigs (BW 28±1.4 kg were assigned to the diets according to a 6×6 Latin square. β-glucan-extract increased apparent total tract digestibility (ATTD of non-glucosyl polysaccharides (accounting for ~40% of the fiber-fraction from rapeseed meal (6%-units, P10%-units, P<0.001, indicating that the large amount of resistant starch entering the hindgut was preferentially degraded over recalcitrant fibers from rapeseed meal and DDGS, possibly related to reduced hindgut-retention time following the increased intestinal bulk. Fermentation of fiber sources was not only dependent on fiber characteristics, but also on the presence of other fibers in the diet. Hence, interactions in the gastrointestinal tract among fibrous feed ingredients should be considered when evaluating their nutritive value.

Obtaining and characterization of a biodegradable polymer starting from the tapioca starch

International Nuclear Information System (INIS)

Ruiz Aviles, Gladys

2006-01-01

This study focuses on the preparation of tapioca starch biodegradable polymer, processed by blends of starch modified with glycerin and water as plasticizers, by using roll mill and a single-screw extruder in the process. During extrusion, there is a series of variables to control namely: the barrel temperature profile, screw torque and screw rotation speed. Tensile test, differential scanning calorimetric (DSC), thermogravimetric analysis (TGA), Fourier transformer infrared spectroscopy (FTIR) and morphology were used in the process

Determination of surface energies of hot-melt extruded sugar-starch pellets.

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Yeung, Chi-Wah; Rein, Hubert

2018-02-01

Hot-melt extruded sugar-starch pellets are an alternative for commercial sugar spheres, but their coating properties remain to be studied. Both the European Pharmcopoeia 8.6 and the United States Pharmacopoeia 40 specify the composition of sugar-starch pellets without giving requirements for the manufacturing process. Due to various fabrication techniques, the physicochemical properties of pellets may differ. Therefore, the adhesion energies of three coating dispersions (sustained, enteric and immediate release) on different types of pellets were investigated. In this context, the surface energies of various kinds of corn starch (normal, waxy, high-amylose) and sucrose pellets were analyzed using the sessile drop method, whereas the surface tensions of the coating dispersions were examined using the pendant drop method. The adhesion forces were calculated from the results of these studies. Furthermore, sugar spheres were characterized in terms of particle size distribution, porosity and specific surface area. An increase of the pellets' sucrose content leads to a more porous surface structure, which gives them an enhanced wetting behavior with coating dispersions. The adhesion energies of extruded sugar-starch pellets are similar to those of commercial sugar spheres, which comply with pharmacopeial requirements. Both types of pellets are equally suited for coating.

Baby corn, green corn, and dry corn yield of corn cultivars

OpenAIRE

Castro,Renato S; Silva,Paulo Sérgio L; Cardoso,Milton J

2013-01-01

In corn, when the first female inflorescence is removed, the plant often produces new female inflorescences. This allows the first ear to be harvested as baby corn (BC) and the second as green corn (GC) or dry corn (DC), that is, mature corn. The flexibility provided by a variety of harvested products allows the grower to compete with better conditions in the markets. We evaluated BC, GC, and DC yields in corn cultivars AG 1051, AG 2060, and BRS 2020, after the first ear was harvested as BC. ...

Effect of glycerol and zinc oxide addition on antibacterial activity of biodegradable bioplastics from chitosan-kepok banana peel starch

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Agustin, Y. E.; Padmawijaya, K. S.

2017-07-01

Bioplastic is a biopolymer plastic that can be degraded easily by microorganisms so it can be used as alternative replaced commercial plastic. This research aims to study the effects of additive (glycerol and zinc oxide) addition in the characteristic of antimicrobial activity and biodegradability bioplastic from chitosan and Kepok banana peel starch. In this research, bioplastics were synthesized by chitosan as the backbone and antimicrobial, Kepok banana peel starch as filler, glycerol as plasticizer, also ZnO as an amplifier. Bioplastics were characterized their antimicrobial activity using agar diffusion method (zone inhibition assay) and biodegradability test using microbe (EM4). The result showed the optimum composition of bioplastic is kitosan 4 - 30% starch - 5 mL glycerol - 5% ZnO gives the good antimicrobial activity towards gram positive and gram negative bacteria, and this bioplastic will be degraded within an hour and 12 min. Thus, this bioplastics may have potential to be use for food packaging by having biodegradable properties and also inhibit bacterial growth.

The properties of poly(lactic acid)/starch blends with a functionalized plant oil: tung oil anhydride.

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Xiong, Zhu; Li, Chao; Ma, Songqi; Feng, Jianxian; Yang, Yong; Zhang, Ruoyu; Zhu, Jin

2013-06-05

Bio-sourced polymers, polylactide (PLA) and starch, have been melt-blended by lab-scale co-extruder with tung oil anhydride (TOA) as the plasticizer. The ready reaction between the maleic anhydride on TOA and the hydroxyl on starch led TOA molecules to accumulate on starch and increased the compatibility of PLA/starch blends, which was confirmed by FT-IR analyses and SEM. The TOA could change the mechanical properties and physical behaviors of PLA/starch blends. DSC and DMA analysis show that the TOA layer on starch has an effect on the thermal behavior of PLA in the ternary blend. The enrichment of TOA on starch improves the toughness and impact strength of the PLA/starch blends. The adding amount of TOA in PLA/starch blends primarily determined the compatibility and mechanical properties of the resulted ternary blends. The tensile and impact fracture modes of the PLA/starch blend with or without TOA has also been investigated by SEM analysis. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Thermogravimetric and Kinetic Analysis of Cassava Starch Based Bioplastic

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Nanang Eko Wahyuningtyas

2017-11-01

Full Text Available Cassava starch based bioplasticfor packaging application has great potency because of the various starch-producing plants in Indonesia.Bioplasticcan contribute to reduce the dependence on fossil fuels andpetroleumthat can solve the environmentalproblem.Thepurpose of this research is to find out the thermal decomposition and the activation energy of cassava starch based bioplastic. The methods weresynthesis bioplastic with cassava starch as main component and glycerol as plasticizer. The thermogravimetry analysis was conducted to obtain the decomposition process mechanism of bioplastic and the heating valueof bioplasticwas measured  using theadiabatic bomb calorimetric.  Data analysis was conducted using  a fitting model approach with an acikalin method to determine the activation energy. The result of thethermogravimetricanalysis showed thatbioplasticisgraduallydecomposedto the moisture, volatilematter, fixed carbon, andash in four stages mechanism. Totally decomposition of bioplastic was 530°C, then all of bioplastic was become the ash. The activation energy in the early and primary thermal decomposition stages are 1.27 kJ/moland 22.62 kJ/mol, respectively and heating valueof bioplastic is 15.16 MJ/kg.

Pasta quality as impacted by the type of flour and starch and the level of egg addition.

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Saleh, Mohammed; Al-Ismail, Khalid; Ajo, Radwan

2017-10-01

This study investigated the effects of substituting wheat flour with fractions of different starch types and egg levels on pasta quality. First order mixture response surface model was used where the effects of various starch types and egg levels on pasta quality were evaluated. Coefficients of estimation were determined and fractional contribution of wheat, starch type and egg levels were evaluated. Egg levels negatively (p egg level from 33 to 0%. Flow behavior index of treatments solution with various fractions of starch types and egg level ranged from 0.34 to 1.42 and was significantly (p cooked pasta quality including firmness, stickiness, cooking loss, and water uptake, keeping with consumer acceptability through varying starch type and egg level. Results show that flour and starch type and egg level interaction play significant role in pasta blends formulation. Moreover, substitution of wheat flour with acorn, native or modified corn and potato starches fractions, as well as with lupine, rice, tapioca, and stabilized rice bran flours would have significant effects on the physical properties and acceptability of various cereal products. For instance, the use of rice bran in potentially developed products would enhance the consumption of whole grain foods, resulting in improved intake of fiber and other healthy components. © 2016 Wiley Periodicals, Inc.

Process development of short-chain polyols synthesis from corn stover by combination of enzymatic hydrolysis and catalytic hydrogenolysis

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Zhen-Hong Fang

2014-09-01

Full Text Available Currently short-chain polyols such as ethanediol, propanediol, and butanediol are produced either from the petroleum feedstock or from the starch-based food crop feedstock. In this study, a combinational process of enzymatic hydrolysis with catalytic hydrogenolysis for short-chain polyols production using corn stover as feedstock was developed. The enzymatic hydrolysis of the pretreated corn stover was optimized to produce stover sugars at the minimum cost. Then the stover sugars were purified and hydrogenolyzed into polyols products catalyzed by Raney nickel catalyst. The results show that the yield of short-chain polyols from the stover sugars was comparable to that of the corn-based glucose. The present study provided an important prototype for polyols production from lignocellulose to replace the petroleum- or corn-based polyols for future industrial applications.

Verification of radio frequency pasteurization treatment for controlling Aspergillus parasiticus on corn grains.

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Zheng, Ajuan; Zhang, Lihui; Wang, Shaojin

2017-05-16

Radio frequency (RF) heating has been proposed and tested to achieve a required anti-fungal efficacy on various food samples due to its advantage of deeper penetration depth and better heating uniformity. The purpose of this study was to validate applications of RF treatments for controlling Aspergillus parasiticus in corn while maintaining product quality. A pilot-scale, 27.12MHz, 6kW RF heating system together with hot air heating was used to rapidly pasteurize 3.0kg corn samples. Results showed that the pasteurizing effect of RF heating on Aspergillus parasiticus increased with increasing heating temperature and holding time, and RF heating at 70°C holding in hot air for at least 12min resulted in 5-6 log reduction of Aspergillus parasiticus in corn samples with the moisture content of 15.0% w.b. Furthermore, thermal resistance of Aspergillus parasiticus decreased with increasing moisture content (MC) of corn samples. Quality (MC, water activity - a w , protein, starch, ash, fat, fatty acid, color, electrical conductivity and germination rate) of RF treated corn met the required quality standard used in cereal industry. Therefore, RF treatments can provide an effective and rapid heating method to control Aspergillus parasiticus and maintain acceptable corn quality. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of corn inclusion on soybean hull-based diet digestibility and growth performance in continuous culture fermenters and beef cattle.

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Russell, J R; Sexten, W J; Kerley, M S

2016-07-01

Two experiments were conducted using soybean hull (SH) diets with increasing corn proportions to determine increasing corn inclusion effects on fermentation characteristics, diet digestibility, and feedlot performance. The hypothesis was that fiber digestibility would quadratically respond to starch proportion in the diet with a break point where starch inclusion improved fiber digestion and feedlot performance. Proportionately, the diets contained 100:0 (SH100), 90:10 (SH90), 80:20 (SH80), 60:40 (SH60), or 20:80 SH:corn (SH20). In Exp. 1, diets were randomly distributed over 24 continuous culture fermenters and fed for 7 d. In Exp. 2, forty steers (347 ± 29 kg BW) and 50 heifers (374 ± 24 kg BW) were blocked by gender, stratified by BW, and distributed across diets. Cattle were fed for 70 d with titanium dioxide included in the diet for the final 14 d and fecal samples collected to measure digestibility. Individual DMI was measured using GrowSafe Feed Intake system. Data were analyzed using the MIXED procedure of SAS with diet evaluated as the fixed effect. In Exp. 1, NDF digestibility (NDFd) linearly decreased ( = 0.04) and ADF digestibility (ADFd) tended to linearly decrease ( = 0.09) as corn increased. Dry matter digestibility (DMd) was cubic ( = 0.01) and OM digestibility (OMd) was quadratic ( = 0.03), and among the 4 SH-based diets, DMd and OMd were greatest for SH90. Acetate:propionate ratio and pH were quadratic ( digestibility decreased as corn inclusion increased. However, based on continuous culture digestibility and VFA values as well as feedlot digestibility and performance, optimal corn inclusion for growth and diet utilization in the 4 SH-based diets fell between SH80 and SH90, or 0.4 and 0.2% BW corn supplementation. In this study, providing 0.4% BW corn supplementation in fiber-based diets (SH80) provided greater improvement in performance compared with 0.2% BW corn supplementation (SH90).

Enzymatically Modified Starch Ameliorates Postprandial Serum Triglycerides and Lipid Metabolome in Growing Pigs.

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Metzler-Zebeli, Barbara U; Eberspächer, Eva; Grüll, Dietmar; Kowalczyk, Lidia; Molnar, Timea; Zebeli, Qendrim

2015-01-01

Developing host digestion-resistant starches to promote human health is of great research interest. Chemically modified starches (CMS) are widely used in processed foods and although the modification of the starch molecule allows specific reduction in digestibility, the metabolic effects of CMS have been less well described. This short-term study evaluated the impact of enzymatically modified starch (EMS) on fasting and postprandial profiles of blood glucose, insulin and lipids, and serum metabolome in growing pigs. Eight jugular-vein catheterized pigs (initial body weight, 37.4 kg; 4 months of age) were fed 2 diets containing 72% purified starch (EMS or waxy corn starch (control)) in a cross-over design for 7 days. On day 8, an 8-hour meal tolerance test (MTT) was performed with serial blood samplings. Besides biochemical analysis, serum was analysed for 201 metabolites through targeted mass spectrometry-based metabolomic approaches. Pigs fed the EMS diet showed increased (Pmetabolome profiling identified characteristic changes in glycerophospholipid, lysophospholipids, sphingomyelins and amino acid metabolome profiles with EMS diet compared to control diet. Results showed rapid adaptations of blood metabolites to dietary starch shifts within 7 days. In conclusion, EMS ingestion showed potential to attenuate postprandial raise in serum lipids and suggested constant alteration in the synthesis or breakdown of sphingolipids and phospholipids which might be a health benefit of EMS consumption. Because serum insulin was not lowered, more research is warranted to reveal possible underlying mechanisms behind the observed changes in the profile of serum lipid metabolome in response to EMS consumption.

Continuous high-solids corn liquefaction and fermentation with stripping of ethanol.

Science.gov (United States)

Taylor, Frank; Marquez, Marco A; Johnston, David B; Goldberg, Neil M; Hicks, Kevin B

2010-06-01

Removal of ethanol from the fermentor during fermentation can increase productivity and reduce the costs for dewatering the product and coproduct. One approach is to recycle the fermentor contents through a stripping column, where a non-condensable gas removes ethanol to a condenser. Previous research showed that this approach is feasible. Savings of $0.03 per gallon were predicted at 34% corn dry solids. Greater savings were predicted at higher concentration. Now the feasibility has been demonstrated at over 40% corn dry solids, using a continuous corn liquefaction system. A pilot plant, that continuously fed corn meal at more than one bushel (25 kg) per day, was operated for 60 consecutive days, continuously converting 95% of starch and producing 88% of the maximum theoretical yield of ethanol. A computer simulation was used to analyze the results. The fermentation and stripping systems were not significantly affected when the CO(2) stripping gas was partially replaced by nitrogen or air, potentially lowering costs associated with the gas recycle loop. It was concluded that previous estimates of potential cost savings are still valid. (c) 2010. Published by Elsevier Ltd. All rights reserved.

Estabilidade de géis de amido de milho normal, ceroso e com alto teor de amilose adicionados de gomas guar e xantana durante os processos de congelamento e descongelamento Freeze-thaw stability of normal, waxy and high amylose corn starch gels with added guar and xanthan gums

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Fernanda Hart Weber

2008-06-01

Full Text Available O objetivo do presente trabalho foi estudar os efeitos das gomas guar e xantana sobre a estabilidade dos géis de amido de milho normal, ceroso e com alto teor de amilose submetidos aos processos de congelamento e descongelamento. Os géis desses amidos, com concentração total de sólidos de 10% e adicionados das gomas (0,15; 0,50; 0,85 e 1%, foram submetidos a 5 ciclos de congelamento (20 horas a -18 °C e descongelamento (4 horas a 25 °C, com exceção dos géis com alto teor de amilose, que foram submetidos a apenas 1 ciclo, devido à perda da estrutura de gel. A determinação da sinérese (porcentagem de água liberada foi realizada pela diferença entre a massa inicial e a massa final das amostras. O gel de amido de milho normal liberou 74,45% de água, sendo que a adição de 1% da goma xantana reduziu significativamente a sinérese para 66,43%. A adição de 0,85 e 1% da goma xantana também reduziu a sinérese dos géis de amido ceroso. O menor teor de sinérese foi obtido com a utilização de 1% de goma xantana ao gel de amido de milho com alto teor de amilose, evidenciando a ação crioprotetora desta goma.The objective of the present work was to study the effects of guar and xanthan gums on the stability of normal, waxy and high amylose corn starch gels, submitted to freeze-thaw processes. The gels of these starches with a total solids content of 10% and added gums (0.15;0.50;0.85and1%, were submitted to 5 freezing (20 hours, -18 °C and thawing (4 hours, 25 °C cycles, with exception of the high amylose gels that were submitted to only 1 cycle. Syneresis (% water released was determined by the difference between the initial and final masses of the samples. The normal corn starch gel released 74.45% water and the addition of 1% xanthan gum significantly reduced syneresis to 66.43%. The incorporation of 0.85 and 1% xanthan gum also reduced syneresis of waxy starch gels. The lowest level of syneresis was reached with the use of 1

Synthesis and properties of fatty acid starch esters.

Science.gov (United States)

Winkler, Henning; Vorwerg, Waltraud; Wetzel, Hendrik

2013-10-15

Being completely bio-based, fatty acid starch esters (FASEs) are attractive materials that represent an alternative to crude oil-based plastics. In this study, two synthesis methods were compared in terms of their efficiency, toxicity and, especially, product solubility with starch laurate (C12) as model compound. Laurates (DS>2) were obtained through transesterification of fatty acid vinylesters in DMSO or reaction with fatty acid chlorides in pyridine. The latter lead to higher DS-values in a shorter reaction time. But due to the much better solubility of the products compared to lauroyl chloride esterified ones, vinylester-transesterification was preferred to optimize reaction parameters, where reaction time could be shortened to 2h. FASEs C6-C18 were also successfully prepared via transesterification. To determine the DS of the resulting starch laurates, the efficient ATR-IR method was compared with common methods (elementary analysis, (1)H NMR). Molar masses (Mw) of the highly soluble starch laurates were analyzed using SEC-MALLS (THF). High recovery rates (>80%) attest to the outstanding solubility of products obtained through transesterification, caused by a slight disintegration during synthesis. Particle size distributions (DLS) demonstrated stable dissolutions in CHCl3 of vinyl laurate esterified - contrary to lauroyl chloride esterified starch. For all highly soluble FASEs (C6-C18), formation of concentrated solutions (10 wt%) is feasible. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effective extraction method through alkaline hydrolysis for the detection of starch maleate in foods

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Chia-Fen Tsai

2015-09-01

Full Text Available A high-performance liquid chromatography (HPLC method was developed for the determination of maleic acid which was released from starch maleate (SM through the alkaline hydrolysis reaction. The proper alkaline hydrolysis conditions and LC separation are reported in this study. The starch samples were treated with 50% methanol for 30 minutes, and then hydrolyzed by 0.5N KOH for 2 hours to release maleic acid. A C18 column and gradient mobile phase consisting of 0.1% phosphoric acid and methanol at a flow rate of 1.0 mL/minute were used for separation. The method showed a good linearity in the range of 0.01–1.0 ìg/mL, with a limit of quantification (LOQ at 10 mg/kg in starch. The recoveries in corn starch, noodle, and fish balls were between 93.9% and 108.4%. The relative standard deviation (RSD of precision was <4.9% (n = 3. This valid method was rapid, sensitive, precise, and suitable for routine monitoring of the illegal adulteration of SM in foods.

A review of the recent advances in starch as active and nanocomposite packaging films

Directory of Open Access Journals (Sweden)

Umar Shah

2015-12-01

Full Text Available Technological advances have led to increased constraints regarding food packaging due to environmental issues, consumer health concerns, and economic restrictions associated therewith. Hence, food scientists and technologists are now more focused on developing biopolymer packages. Starch satisfies all the principle aspects, making it a promising raw material for edible coatings/films. Starch as a package material has grabbed much attention both at academic as well as industrial levels. Besides this, the role of various plasticizers, polys, sugars, and wetting agents are discussed and their importance in packaging industries. Herein, the role of starch as packaging material and nanofillers/composites is discussed in detail. The review summons a comprehensive and current overview of the widely available information and recent advances in starch film packaging.

Determination of dietary starch in animal feeds and pet food by an enzymatic-colorimetric method: collaborative study.

Science.gov (United States)

Hall, Mary Beth

2015-01-01

testing laboratories analyzed 10 homogenous test materials representing animal feedstuffs and pet foods in duplicate using the dietary starch assay. The test samples ranged from 1 to 70% in dietary starch content and included moist canned dog food, alfalfa pellets, distillers grains, ground corn grain, poultry feed, low starch horse feed, dry dog kibbles, complete dairy cattle feed, soybean meal, and corn silage. The average within-laboratory repeatability SD (sr) for percentage dietary starch in the test samples was 0.49 with a range of 0.03 to 1.56, and among-laboratory repeatability SDs (sR) averaged 0.96 with a range of 0.09 to 2.69. The HorRat averaged 2.0 for all test samples and 1.9 for test samples containing greater than 2% dietary starch. The HorRat results are comparable to those found for AOAC Method 996.11, which measures starch in cereal products. It is recommended that the dietary starch method be accepted for Official First Action status.

Preparation of 5-hydroxymethylfurfuraldehyde from high fructose corn syrup and other carbohydrates

Energy Technology Data Exchange (ETDEWEB)

Szmant, H H; Chundury, D D

1981-01-01

5-Hydroxymethylfurfuraldehyde (HMF) was prepared from high fructose corn syrup (HFCS), or crystalline D-fructose, in high yield and purity. A 95%-97% conversion of fructose to HMF was achieved using 25 mol% (based on fructose) boron trifluoride etherate catalyst in dimethyl sulphoxide, under a nitrogen atmosphere, a reaction temperature of 273 K, and 30 minutes reaction time. Inferior yields of HMF were obtained from glucose and starch.

Compatibilizing role of carbon nanotubes in poly(vinyl alcohol)/starch blend

KAUST Repository

Jose, Jobin Vinodh

2014-10-03

Polymer nanocomposites based on poly(vinyl alcohol)/starch blend and carbon nanotubes (CNT) were prepared by solution mixing, followed by casting. Glycerol was used as a plasticizer and added in the starch dispersion. The uniform dispersion of CNT in water before mixing with PVA/starch blend, was achieved by using an Ultrasonicator probe. The composites were characterized by measurement of tensile properties, thermal analysis, FE-SEM, TEM, XRD studies, and water uptake. It was observed that the decrease in tensile strength, modulus, and elongation at break on addition of starch into PVA can be arrested by incorporation of CNT. The strong physical bonding such as hydrogen bonding among the hydroxyl groups of polymer components and oxygen containing groups on CNT surface resulted in a more tortuous path for the water to follow, lowering of water uptake. Thermal analysis and spectroscopic images showed an increase in blend homogeneity in the presence of CNT.

Effect of castor oil enrichment layer produced by reaction on the properties of PLA/HDI-g-starch blends.

Science.gov (United States)

Xiong, Zhu; Zhang, Lisheng; Ma, Songqi; Yang, Yong; Zhang, Chuanzhi; Tang, Zhaobin; Zhu, Jin

2013-04-15

Blends of entirely bio-sourced polymers, namely polylactide (PLA) and starch, have been melt-compounded by lab-scale co-extruder with castor oil (CO) as a plasticizer. The enrichment of castor oil on starch had great effect on the properties of the blends. If the castor oil was mainly dispersed in PLA matrix, the properties of the blends were poor, but when the hexamethylenediisocyanate (HDI) was grafted on starch granules the ready reactions between the hydroxyl on CO and the isocyante on the HDI-grafted starch (HGSTs) brought CO molecules enriched on starch particles. DSC analysis shows that the CO layer on starch has a positive effect on the crystallization of PLA in the ternary blend. The accumulation of CO on starch greatly improves the toughness and impact strength of PLA/starch blends. The grafting content of HDI on the starch granules primarily determined the compatibility and properties of the resulted blends. Copyright © 2013 Elsevier Ltd. All rights reserved.

Analysis of Biodegradation of Bioplastics Made of Cassava Starch

Directory of Open Access Journals (Sweden)

Nanang Eko Wahyuningtiyas

2017-08-01

Full Text Available Environmental pollution due to plastic waste taking too long to decompose has become a global problem. There have been numerous solutions proposed, one of which is the use of bioplastics. The use of cassava starch as the main ingredient in the manufacture of bioplastics shows great potential, since Indonesia has a diverse range of starch-producing plants. The aim of the present study is to analyse the effect of glycerol on microbial degradation. This experimental research investigated the use of cassava flour mixed with glycerol plasticizer at various concentrations (0, 2, 2.5, 3% in the synthesis of bioplastics. The aspects studied were biodegradability, moisture absorption (using ASTM D570, shelf life, and morphological properties (using a camera equipped with a macro lens and SEM. This study revealed that complete degradation could be achieved on the 9th day. The addition of a large concentration of glycerol would accelerate the microbial degradation process, increase moisture, and extend the shelf life of bioplastics in a dry place.

Evaluation of thermoplastic starch/MMT nanocomposites by nuclear magnetic resonance (NMR); Avaliacao de nanocompositos de amido termoplastico e argila por RMN

Energy Technology Data Exchange (ETDEWEB)

Schlemmer, D.; Rodrigues, Tiago C.A.F.; Resck, I.S.; Sales, M.J.A., E-mail: danielas@unb.b [Universidade de Brasilia (LabPol/UnB), DF (Brazil). Inst. de Quimica. Lab. de Pesquisa em Polimeros

2010-07-01

Starch has been studied for replace petrochemical plastics for short shelf life. However, the starch films have limitations: sensitivity to moisture and poor mechanical strength. This can be improved by incorporating loads such as montmorillonite, forming nanocomposites. Nanocomposites were prepared with 1, 3, 5 and 10% of montmorillonite, using vegetable oils of Brazilian Cerrado as plasticizers. The NMR spectra of oils are similar, but the intensities of the signals varying with the proportion of fatty acids. The molar mass of the oils was also calculated by NMR. The spectrum of CP/MAS {sup 13}C NMR for starch presented a duplet in 97 and 98 ppm, on the amorphous domains of C-1, indicating a crystal type A. The spectra of the nanocomposites are similar to those of starch and oils. No new peaks appear, suggesting that there are no strong chemical bonds between components. (author)

Estudo termoanalítico, CLAE e francionamento físico e químico do subproduto industrial do milho Thermoalytical study, HPLC and physical and chemical cracking from corn industry co-product

Directory of Open Access Journals (Sweden)

Cheila G. Mothé

2005-03-01

Full Text Available O fracionamento do farelo de milho desengordurado (fubá grosso, subproduto do processamento industrial do milho, para obtenção de frações de amido, proteínas e fibras, utilizando métodos físicos e químicos, foi investigado. O fracionamento do fubá grosso por meio de tratamento químico com soluções de bissulfito de sódio e de etanol, foi satisfatório, pois produziu fração de amido com aceitável rendimento; já o fracionamento físico não foi muito eficiente, visto que não produziu fração enriquecida de proteínas e amido. Tanto o fubá grosso como as frações obtidas, foram caracterizados por meio de CLAE (Cromatografia Líquida de Alta Eficiência e Análise Térmica (TG, DTG e DSC. O fubá grosso possui mais de 50% de amido (CLAE, e perda de 52% de sua massa entre 270 e 450ºC (TG e DTG. O estudo cinético, a partir de curvas DSC, mostrou que os processos de gelatinização da fração de amido e de desnaturação da fração de proteínas são eventos endotérmicos, com diferentes valores de entalpia e de energia de ativação.The cracking of the defatted corn germ (thick corn meal, co-product from corn industry processing, to obtain starch, proteins and fiber fractions using physical and chemical methods has been investigated. The chemical separation of the thick corn meal with sodium disulfide and ethanol solutions was satisfactory, since it had product starch fraction with acceptable yield. However, the physical separation (boll mill was not successful, because it has not yielded enriched fractions of starch and proteins. Both thick corn meal and all the fractions obtained were characterized by HPLC (High Performance Liquid Chromatography and Thermal Analysis (TG, DTG and DSC. The thick corn meal is composed of more than 50% of starch (CLAE. It has showed mass loss of 52% between 270 - 450ºC (TG and DTG. The kinetic parameters from DSC curves exhibited for gelatinization process of the starch fractions and

Reduction of abdominal fat accumulation in rats by 8-week ingestion of a newly developed sweetener made from high fructose corn syrup.

Science.gov (United States)

Iida, Tetsuo; Yamada, Takako; Hayashi, Noriko; Okuma, Kazuhiro; Izumori, Ken; Ishii, Reika; Matsuo, Tatsuhiro

2013-06-01

Many studies have shown that ingestion of high-fructose corn syrup (HFCS) may cause an increase in body weight and abdominal fat. We recently developed a new sweetener containing rare sugars (rare sugar syrup; RSS) by slight isomerization of HFCS. Here, the functional effects of RSS on body weight and abdominal fat, and biochemical parameters in Wistar rats were examined. Rats (n=30) were randomly divided into three groups and maintained for 8-weeks on starch, starch+HFCS (50:50), and starch+RSS (50:50) diets. Rats in the Starch and HFCS groups gained significantly more body weight and abdominal fat than the RSS group. Fasting serum insulin in the RSS group was significantly lower than in the Starch and HFCS groups, although serum glucose in the HFCS and RSS groups was significantly lower than that in the Starch group. Thus, the substitution of HFCS with RSS prevents obesity induced by the consumption of HFCS. Copyright © 2012 Elsevier Ltd. All rights reserved.

Influence of ionizing radiation and use of plasticizers on the mechanical properties and barrier properties of biodegradable films

International Nuclear Information System (INIS)

Ponce, Patricia; Parra, Duclerc F.; Carr, Laura G.; Sato, Juliana S.; Lugao, Ademar B.

2005-01-01

This work reports the influence of radiation and plasticizers on the barrier properties [water vapour permeability (WVP)] and mechanical properties (tensile strength and elongation) of edible films made of starch. These films were prepared with 4 g of starch/100 mL of water; 2-10 g polyethylene glycol (PEG)/100 g starch; and at natural pH. Tensile strength and percentage elongation were measured using a Mechanical Universal Testing Machine Instron 4400R and the water vapour permeability was determined according to ASTM E96-80 (ASTM, 1989). The mechanical properties of starch films are influenced by the plasticizer concentration. An increase in PEG content showed a considerable increase in elongation percentage and a decrease in the tensile strength of the films, also increase the permeability of the films in water. After irradiation, the barrier properties [water vapour permeability (WVP)] and mechanical properties (tensile strength and elongation) of the films were improved due to chemical reactions among polymer molecules. The films were irradiated at room temperature with gamma radiation. Irradiated starch cassava films with polyethylene glycol (PEG) as plasticizer have good flexibility and low water permeability, which indicate potential application as edible films (author)

Starch bioengineering

DEFF Research Database (Denmark)

Blennow, Andreas

2018-01-01

Application of starch in industry frequently requires extensive modification. This is usually achieved by chemical and/or physical modification that is time-consuming and often expensive and polluting. To impart functionality as early as possible in the starch production chain, modification can...... be achieved directly as part of the developing starch storage roots, tubers, and seeds and grains of the crop. Starch has been a strong driver for human development and is now the most important energy provider in the diet forcing the development of novel and valuable starch qualities for specific...... applications. Among the most important structures that can be targeted include starch phosphorylation chain transfer/branching generating chemically substituted and chain length-modified starches such as resistant and health-promoting high-amylose starch. Starch bioengineering has been employed for more than...

Improving the corn-ethanol industry: studying protein separation techniques to obtain higher value added product options for distillers grains

NARCIS (Netherlands)

Brehmer, B.; Bals, B.; Sanders, J.P.M.; Dale, B.

2008-01-01

Currently in America the biofuel ethanol is primarily being produced by the dry grind technique to obtain the starch contained in the corn grains and subsequently subjected to fermentation. This so-called 1st generation technology has two setbacks; first the lingering debate whether its life cycle

Stochastic Corn Yield Response Functions to Nitrogen for Corn after Corn, Corn after Cotton, and Corn after Soybeans

OpenAIRE

Boyer, Christopher N.; Larson, James A.; Roberts, Roland K.; McClure, Angela T.; Tyler, Donald D.; Zhou, Vivian

2013-01-01

Deterministic and stochastic yield response plateau functions were estimated to determine the expected profit-maximizing nitrogen rates, yields, and net returns for corn grown after corn, cotton, and soybeans. The stochastic response functions were more appropriate than their deterministic counterparts, and the linear response stochastic plateau described the data the best. The profit-maximizing nitrogen rates were similar for corn after corn, cotton, and soybeans, but relative to corn after ...

Effect of the incorporation of antimicrobial/antioxidant proteins on the properties of potato starch films.

Science.gov (United States)

Moreno, Olga; Atarés, Lorena; Chiralt, Amparo

2015-11-20

Glycerol plasticized potato starch films containing bioactive proteins (lactoferrin (LF) and/or lysozyme (LZ), at 0.1 and 0.2 ratio with respect to starch) were obtained by casting method and characterized as to their microstructural, thermal and physical (water content, mechanical, water and oxygen barrier, optical) properties. The bioactive properties, named antioxidant and antimicrobial, of the proteins and the films were also characterized. The incorporation of proteins affected the structural and physical properties of potato starch films, while modifying their thermal behavior and increasing the glass transition temperature. Both proteins showed a certain degree of compatibility with starch chains through the bond formations (increase in Tg), while a part is separated and migrates to the film surface. Their incorporation, especially that of lactoferrin, greatly increased the film's brittleness, regardless of the films water content, although they enhance the water vapor and oxygen barrier properties, whatever the age of the film. Protein also reduced the film's transparency and gloss, while lactoferrin induced color changes. The thermal degradation of blend films and isolated proteins occurred at temperatures of over 250°C, which means that blend starch films can be thermoprocessed, according to their thermoplastic properties and following the usual practices of the plastics industries. A synergistic antimicrobial action against Escherichia coli and coliforms was observed when both LZ and LF were simultaneously applied. Both of these exhibited antioxidant capacity. Copyright © 2015. Published by Elsevier Ltd.

Succinic Acid as a Byproduct in a Corn-based Ethanol Biorefinery

Energy Technology Data Exchange (ETDEWEB)

MBI International

2007-12-31

MBI endeavored to develop a process for succinic acid production suitable for integration into a corn-based ethanol biorefinery. The project investigated the fermentative production of succinic acid using byproducts of corn mill operations. The fermentation process was attuned to include raw starch, endosperm, as the sugar source. A clean-not-sterile process was established to treat the endosperm and release the monomeric sugars. We developed the fermentation process to utilize a byproduct of corn ethanol fermentations, thin stillage, as the source of complex nitrogen and vitamin components needed to support succinic acid production in A. succinogenes. Further supplementations were eliminated without lowering titers and yields and a productivity above 0.6 g l-1 hr-1was achieved. Strain development was accomplished through generation of a recombinant strain that increased yields of succinic acid production. Isolation of additional strains with improved features was also pursued and frozen stocks were prepared from enriched, characterized cultures. Two recovery processes were evaluated at pilot scale and data obtained was incorporated into our economic analyses.

Integral use of amaranth starch to obtain cyclodextrin glycosyltransferase, by Bacillus megaterium, to produce β-cyclodextrin.

Directory of Open Access Journals (Sweden)

María Belem Arce-Vázquez

2016-09-01

Full Text Available Cyclodextrin glycosyltransferase (CGTase is an enzyme that produces cyclodextrins (CDs from starch and related carbohydrates, producing a mixture of α-, β-, and γ-CDs in different amounts. CGTase production, mainly by Bacillus sp., depends on fermentation conditions such as pH, temperature, concentration of nutrients, carbon and nitrogen sources, among others. Bacillus megaterium CGTase produces those three types of CDs, however, β-CD should prevail. Although waxy corn starch (CS is used industrially to obtain CGTase and CDs because of its high amylopectin content, alternative sources such as amaranth starch (AS could be used to accomplish those purposes. AS has high susceptibility to the amylolytic activity of CGTase because of its 80% amylopectin content. Therefore, the aim of this work was evaluate the AS as carbon source for CGTase production by B. megaterium in a submerged fermentation. Afterwards, the CGTase was purified partially and its activity to synthesize α-, β- and γ-CDs was evaluated using 1% AS as substrate. B. megaterium produced a 66 kDa CGTase (Topt=50°C; pHopt=8.0, from the early exponential growth phase which lasted 36 h. The maximum CGTase specific activity (106.62±8.33 U/mg protein was obtained after 36 h of culture. CGTase obtained with a Km=0.152 mM and a Vmax=13.4 µM/min yielded 40.47% total CDs using AS which was roughly twice as much as that of corn starch (CS; 24.48%. High costs to produce CDs in the pharmaceutical and food industries might be reduced by using AS because of its higher α-, β- and γ-CDs production (12.81%, 17.94% and 9.92%, respectively in a shorter time than that needed for CS.

Preparation and physicochemistry properties of smart edible films based on gelatin-starch nanoparticles.

Science.gov (United States)

Tao, Furong; Shi, Chengmei; Cui, Yuezhi

2018-04-24

Among the natural polymers able to form edible films, starch and gelatin (Gel) are potential sources. Corn starch is a polysaccharide widely produced around the world, and gelatin differs from other hydrocolloids as a fully digestible protein, containing nearly all the essential amino acids, except tryptophan. Based on this, with advantages such as abundance, relatively low cost, biodegradability, and edibility, studies considering alternative systems for food protection that utilize biopolymers have increased significantly in the recent years. A novel macromolecular crosslinker Starch-BTCAD-NHS (starch - butanetetracarboxylic acid dianhydride - N-hydroxysuccinimide, SBN) was successfully prepared to modify gelatin film. Compared with the blank gelatin films, the resulting SBN-Gel films exhibited the improved surface hydrophobicity, the higher tense strength and elongation-at-break, the lower Young's modulus values, the greater opacity, the poorer water vapor uptake properties and better anti-degradation capacity. The modified gelatin film material with advanced properties obtained in this work was safe, stable eco-friendly and biorefractory, and was an ideal choice to form a packaging in food industry. Also, the crosslinking SBN-gelatin coating was effective in reducing the corruption and extending the shelf life for the peeled apple substantially. This article is protected by copyright. All rights reserved.