Influence of botanic origin and amylose content on the morphology of starch nanocrystals

International Nuclear Information System (INIS)

LeCorre, Déborah; Bras, Julien; Dufresne, Alain

2011-01-01

Starch nanocrystals (SNC) are crystalline platelets resulting from the disruption of the semi-crystalline structure of starch granules by the acid hydrolysis of amorphous parts. The aim of this study was to assess the influence of botanic origin and amylose content of native starches on the morphology and properties of resulting nanoparticles. SNC were prepared from five different starches normal maize, high amylose maize, waxy maize, potato, and wheat; covering three botanic origins, two crystalline types, and three range of amylose content (0, 25, and 70%) for maize starch. Different types of nanocrystals were obtained with a thickness ranging between 4 and 8 nm and diameter from about 50 to 120 nm depending on the source. The comparison of their morphology, crystallinity, and rheological properties is proposed for the first time. For the same amylose content, maize, potato, and wheat resulted in rather similar size and crystallinity of SNC proving the limited influence of the botanic origin. For the same botanic origin (maize), differences in size were more important indicating the influence of the amylopectin content. Also, particles tended to show square shapes with increasing native starch’s amylopectin content and A-type crystalinity. Thus, only high amylose content starches should be avoided to prepare SNC.

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.

Effect of high temperature on grain filling period, yield, amylose content and activity of starch biosynthesis enzymes in endosperm of basmati rice.

Science.gov (United States)

Ahmed, Nisar; Tetlow, Ian J; Nawaz, Sehar; Iqbal, Ahsan; Mubin, Muhammad; Nawaz ul Rehman, Muhammad Shah; Butt, Aisha; Lightfoot, David A; Maekawa, Masahiko

2015-08-30

High temperature during grain filling affects yield, starch amylose content and activity of starch biosynthesis enzymes in basmati rice. To investigate the physiological mechanisms underpinning the effects of high temperature on rice grain, basmati rice was grown under two temperature conditions - 32 and 22 °C - during grain filling. High temperature decreased the grain filling period from 32 to 26 days, reducing yield by 6%, and caused a reduction in total starch (3.1%) and amylose content (22%). Measurable activities of key enzymes involved in sucrose to starch conversion, sucrose synthase, ADP-glucose pyrophosphorylase, starch phosphorylase and soluble starch synthase in endosperms developed at 32 °C were lower than those at 22 °C compared with similar ripening stage on an endosperm basis. In particular, granule-bound starch synthase (GBSS) activity was significantly lower than corresponding activity in endosperms developing at 22 °C during all developmental stages analyzed. Results suggest changes in amylose/amylopectin ratio observed in plants grown at 32 °C was attributable to a reduction in activity of GBSS, the sole enzyme responsible for amylose biosynthesis. © 2014 Society of Chemical Industry.

Mechanical and barrier properties of maize starch-gelatin composite films: effects of amylose content.

Science.gov (United States)

Wang, Kun; Wang, Wenhang; Ye, Ran; Xiao, Jingdong; Liu, Yaowei; Ding, Junsheng; Zhang, Shaojing; Liu, Anjun

2017-08-01

In order to obtain new reinforcing bio-fillers to improve the physicochemical properties of gelatin-based films, three types of maize starch, waxy maize starch (Ap), normal starch (Ns) and high-amylose starch (Al), were incorporated into gelatin film and the resulting film properties were investigated, focusing on the impact of amylose content. The thickness, opacity and roughness of gelatin film increased depending on the amylose content along with the starch concentration. The effects of the three starches on the mechanical properties of gelatin film were governed by amylose content, starch concentration as well as environmental relative humidity (RH). At 75% RH, the presence of Al and Ns in the gelatin matrix increased the film strength but decreased its elongation, while Ap exhibited an inverse effect. Starch addition decreased the oxygen permeability of the film, with the lowest value at 20% Al and Ns. All starches, notably at 30% content, led to a decrease in the water vapor permeability of the film at 90% RH, especially Ns starch. Furthermore, the starches improved the thermal stability of the film to some extent. Fourier transform infrared spectra indicated that some weak intermolecular interactions such as hydrogen bonding occurred between gelatin and starch. Moreover, a high degree of B-type crystallinity of starch was characterized in Gel-Al film by X-ray diffraction. Tailoring the properties of gelatin film by the incorporation of different types of maize starch provides the potential to extend its applications in edible food packaging. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Rheological Properties and Electrospinnability of High-Amylose Starch in Formic Acid.

Science.gov (United States)

Lancuški, Anica; Vasilyev, Gleb; Putaux, Jean-Luc; Zussman, Eyal

2015-08-10

Starch derivatives, such as starch-esters, are commonly used as alternatives to pure starch due to their enhanced mechanical properties. However, simple and efficient processing routes are still being sought out. In the present article, we report on a straightforward method for electrospinning high-amylose starch-formate nanofibers from 17 wt % aqueous formic acid (FA) dispersions. The diameter of the electrospun starch-formate fibers ranged from 80 to 300 nm. The electrospinnability window between starch gelatinization and phase separation was determined using optical microscopy and rheological studies. This window was shown to strongly depend on the water content in the FA dispersions. While pure FA rapidly gelatinized starch, yielding solutions suitable for electrospinning within a few hours at room temperature, the presence of water (80 and 90 vol % FA) significantly delayed gelatinization and dissolution, which deteriorated fiber quality. A complete destabilization of the electrospinning process was observed in 70 vol % FA dispersions. Optical micrographs showed that FA induced a disruption of starch granule with a loss of crystallinity confirmed by X-ray diffraction. As a result, starch fiber mats exhibited a higher elongation at break when compared to brittle starch films.

PROTEIN TARGETING TO STARCH is required for localising GRANULE-BOUND STARCH SYNTHASE to starch granules and for normal amylose synthesis in Arabidopsis.

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David Seung

2015-02-01

Full Text Available The domestication of starch crops underpinned the development of human civilisation, yet we still do not fully understand how plants make starch. Starch is composed of glucose polymers that are branched (amylopectin or linear (amylose. The amount of amylose strongly influences the physico-chemical behaviour of starchy foods during cooking and of starch mixtures in non-food manufacturing processes. The GRANULE-BOUND STARCH SYNTHASE (GBSS is the glucosyltransferase specifically responsible for elongating amylose polymers and was the only protein known to be required for its biosynthesis. Here, we demonstrate that PROTEIN TARGETING TO STARCH (PTST is also specifically required for amylose synthesis in Arabidopsis. PTST is a plastidial protein possessing an N-terminal coiled coil domain and a C-terminal carbohydrate binding module (CBM. We discovered that Arabidopsis ptst mutants synthesise amylose-free starch and are phenotypically similar to mutants lacking GBSS. Analysis of granule-bound proteins showed a dramatic reduction of GBSS protein in ptst mutant starch granules. Pull-down assays with recombinant proteins in vitro, as well as immunoprecipitation assays in planta, revealed that GBSS physically interacts with PTST via a coiled coil. Furthermore, we show that the CBM domain of PTST, which mediates its interaction with starch granules, is also required for correct GBSS localisation. Fluorescently tagged Arabidopsis GBSS, expressed either in tobacco or Arabidopsis leaves, required the presence of Arabidopsis PTST to localise to starch granules. Mutation of the CBM of PTST caused GBSS to remain in the plastid stroma. PTST fulfils a previously unknown function in targeting GBSS to starch. This sheds new light on the importance of targeting biosynthetic enzymes to sub-cellular sites where their action is required. Importantly, PTST represents a promising new gene target for the biotechnological modification of starch composition, as it is

Preparation and properties of amylose complexes prepared from hexadecylamine and its hydrochloride salt

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Amylose inclusion complexes were prepared from jet-cooked aqueous mixtures of high amylose corn starch and 1-hexadecylamine (HDA). Slow-cooling produced torus/disc-shaped spherulites, whereas aggregates of smaller spherulites were obtained by rapid-cooling in ice. The morphologies and 6(1)V x-ray ...

Increased water resistance of paper treated with amylose-fatty ammonium salt inclusion complexes

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Amylose inclusion complexes were prepared from high amylose corn starch and the HCl salts of hexadecylamine and octadecylamine. Solutions of the complexes were applied to paper at concentrations of 2-4%. After the treated papers were dried, sodium hydroxide solution was applied to convert the adsorb...

Resistant Starch: Variation among High Amylose Rice Varieties and Its Relationship with Apparent Amylose Content, Pasting Properties and Cooking Methods

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Resistant starch (RS), which is not hydrolyzed in the small intestines, has proposed health benefits. We evaluated a set of 40 high amylose rice varieties for RS levels in cooked rice and approximately a 1.9-fold difference was found. The highest ones had more than two-fold greater RS concentration ...

Creation of a high-amylose durum wheat through mutagenesis of starch synthase II (SSIIa)

Science.gov (United States)

In cereal seeds mutations in one or more starch synthases lead to decreased amylopectin and increased amylose content. Here, the impact of starch synthase IIa (SSIIa or SGP-1) mutations upon durum starch was investigated. A screen of durum accessions identified two lines lacking SGP-A1, the A geno...

Impact of full range of amylose contents on the architecture of starch granules.

Science.gov (United States)

Goldstein, Avi; Annor, George; Putaux, Jean-Luc; Hebelstrup, Kim H; Blennow, Andreas; Bertoft, Eric

2016-08-01

The effects of amylose deposition on crystalline regions of barley starch granules were studied in granules containing zero to 99.1% amylose using "waxy" (WBS, 0% amylose), normal (NBS, 18% amylose) and amylose-only barley lines (AOS, 99.1% amylose). The effects were probed after hydrolysis of amorphous regions of starch granules in dilute HCl generating lintners, which typically represent the crystalline lamella of starch granules. Compared to NBS and WBS, AOS granules exhibited an irregular, multilobular morphology with a rough surface texture. AOS displayed lower rates of acid hydrolysis than WBS, and AOS reached a plateau at ∼45wt% acid hydrolysis. High-performance anion-exchange chromatography of lintners at equivalent levels of hydrolysis (45wt%) revealed the average degree of polymerization (DP) of AOS lintners was 21, substantially smaller than that of NBS and WBS (DP 42). AOS lintners contained the lowest number of chains (NC) per molecule (1.1) compared to NBS (2.8) and WBS (3.3) and the average chain length of AOS, NBS and WBS lintners was 19, 15 and 13, respectively. Hence, both NC and the average chain length correlated with amylose content. The size distribution profile of AOS lintners revealed a repeat motif in the molecules corresponding to 5-6 glucose residues. Copyright © 2016 Elsevier B.V. All rights reserved.

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.

Higher value films prepared from poly(vinyl alcohol) and amylose-fatty acid derivatives inclusion complexes

Science.gov (United States)

Water soluble amylose fatty acid and fatty ammonium salt inclusion complexes (AIC) were prepared by jet cooked high amylose corn starch with water soluble salts of long chain fatty acids or fatty amines. The formation of AIC was confirmed by X-ray diffraction of freeze-dried samples. After dissoluti...

Impact of full range of amylose contents on the architecture of starch granules*

DEFF Research Database (Denmark)

Goldstein, Avi; Annor, George; Putaux, Jean Luc

2016-01-01

The effects of amylose deposition on crystalline regions of barley starch granules were studied in granules containing zero to 99.1% amylose using "waxy" (WBS, 0% amylose), normal (NBS, 18% amylose) and amylose-only barley lines (AOS, 99.1% amylose). The effects were probed after hydrolysis of am...

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

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.

Apparent mineral retention is similar in control and hyperinsulinemic men after consumption of high amylose cornstarch.

Science.gov (United States)

Behall, Kay M; Howe, Juliette C; Anderson, Richard A

2002-07-01

The effects on apparent mineral retention after long-term consumption of a high amylose diet containing 30 g resistant starch (RS) were investigated in 10 control and 14 hyperinsulinemic men. Subjects consumed products (bread, muffins, cookies, corn flakes and cheese puffs) made with standard (70% amylopectin, 30% amylose; AP) or high amylose (70% amylose, 30% amylopectin; AM) cornstarch for two 14-wk periods in a crossover pattern. Starch products replaced usual starches in the habitual diet for 10 wk followed by 4 wk of consuming the controlled diets. During wk 12, all urine, feces and duplicate foods were collected for 7 d. Urinary chromium losses after a glucose tolerance test or 24-h collections of the hyperinsulinemic and control subjects did not differ and were not altered by diet. Except for zinc, the two subject types did not differ significantly in apparent mineral balance. Apparent retentions of calcium and magnesium were not significantly affected by diet (AM vs. AP) or type-by-diet interaction. Apparent iron retention tended to be greater after AM than AP consumption (P copper retention was greater after consuming AP than after AM (P < 0.02), whereas apparent zinc retention was greater after consuming AM than after AP (P < 0.018). Zinc also showed a significant type-by-diet interaction (P < 0.034) with control subjects retaining less zinc after consuming AP than after AM. In summary, a high amylose cornstarch diet containing 30 g RS could be consumed long term without markedly affecting, and possibly enhancing, retention of some minerals.

Complementation of the amylose-free starch mutant of potato (Solanum tuberosum.) by the gene encoding granule-bound starch synthase

NARCIS (Netherlands)

van der Leij, E.R.; Visser, R.G.E.; OOSTERHAVEN, K; VANDERKOP, DAM; Jacobsen, E.; Feenstra, W.

1991-01-01

Agrobacterium rhizogenes-mediated introduction of the wild-type allele of the gene encoding granule-bound starch synthase (GBSS) into the amylose-free starch mutant amf of potato leads to restoration of GBSS activity and amylose synthesis, which demonstrates that Amf is the structural gene for GBSS.

Effect of defatting on acid hydrolysis rate of maize starch with different amylose contents.

Science.gov (United States)

Wei, Benxi; Hu, Xiuting; Zhang, Bao; Li, Hongyan; Xu, Xueming; Jin, Zhengyu; Tian, Yaoqi

2013-11-01

The effect of defatting on the physiochemical properties and the acid hydrolysis rate of maize starch with different amylose contents was evaluated in this study. The increase in the number of pores and the stripping of starch surface layers were observed after defatting by scanning electron microscopy. X-ray diffraction spectrum showed that the peaks attributing to the amylose-lipid complex disappeared. The relative crystallinity increased by 19% for high-amylose maize starch (HMS) on defatting, while the other tested starches virtually unchanged. Differential scanning calorimetry study indicated an increase in the thermal stability for the defatted starches. Compared with native waxy maize starch, the acid hydrolysis rate of the defatted one increased by 6% after 10 days. For normal maize starch (NMS) and HMS, the higher rate of hydrolysis was observed during the first 5 days. Thereafter, the hydrolysis rate was lower than that of their native counterpart. The increase in susceptibility to acid hydrolysis (in the first 5 days) was mainly attributed to the defective and porous structures formed during defatting process, while the decrease of hydrolysis rate for NMS and HMS samples (after the first 5 days) probably resulted from the increase in the relative crystallinity. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

Production of high-amylose maize lines using RNA interference in ...

African Journals Online (AJOL)

amylose maize lines with a low T-DNA copy number, demonstrating that RNAi is an efficient method for the production of high-amylose maize lines. Key words: Maize, high-amylose, RNA interference, starch branching enzyme gene sbe2a.

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.

Sensory characteristics of high-amylose maize-resistant starch in three food products

OpenAIRE

Maziarz, Mindy; Sherrard, Melanie; Juma, Shanil; Prasad, Chandan; Imrhan, Victorine; Vijayagopal, Parakat

2012-01-01

Type 2 resistant starch from high-amylose maize (HAM-RS2) is considered a functional ingredient due to its positive organoleptic and physiochemical modifications associated with food and physiological benefits related to human health. The sensory characteristics of three types of food products (muffins, focaccia bread, and chicken curry) with and without HAM-RS2 were evaluated using a 9-point hedonic scale. The HAM-RS2-enriched muffins, focaccia bread, and chicken curry contained 5.50 g/100 g...

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

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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.

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

A novel wheat variety with elevated content of amylose increases resistant starch formation and may beneficially influence glycaemia in healthy subjects

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Elin Östman

2011-08-01

Full Text Available Previous studies indicate that elevated amylose content in products from rice, corn, and barley induce lower postprandial glycaemic responses and higher levels of resistant starch (RS. Consumption of slowly digestible carbohydrates and RS has been associated with health benefits such as decreased risk of diabetes and cardiovascular disease.To evaluate the postprandial glucose and insulin responses in vivo to bread products based on a novel wheat genotype with elevated amylose content (38%.Bread was baked from a unique wheat genotype with elevated amylose content, using baking conditions known to promote amylose retrogradation. Included test products were bread based on whole grain wheat with elevated amylose content (EAW, EAW with added lactic acid (EAW-la, and ordinary whole grain wheat bread (WGW. All test breads were baked at pumpernickel conditions (20 hours, 120°C. A conventionally baked white wheat bread (REF was used as reference. Resistant starch (RS content was measured in vitro and postprandial glucose and insulin responses were tested in 14 healthy subjects.The results showed a significantly higher RS content (on total starch basis in breads based on EAW than in WGW (p<0.001. Lactic acid further increased RS (p<0.001 compared with both WGW and EAW. Breads baked with EAW induced lower postprandial glucose response than REF during the first 120 min (p<0.05, but there were no significant differences in insulin responses. Increased RS content per test portion was correlated to a reduced glycaemic index (GI (r= − 0.571, p<0.001.This study indicates that wheat with elevated amylose content may be preferable to other wheat genotypes considering RS formation. Further research is needed to test the hypothesis that bread with elevated amylose content can improve postprandial glycaemic response.

Pasting, rheological, and retrogradation properties of low-amylose rice starch with date syrup.

Science.gov (United States)

Mohamed, Ibrahim O; Babucurr, Jobe

2017-09-01

Effects of date syrup on pasting, rheological, and retrogradation properties of low-amylose rice starch were investigated using three levels of date syrup (starch:syrup 1:1, 1:2, or 1:3). Measurements were carried out using HR-2 Discovery Rheometer equipped with a pasting cell and parallel plate geometry. The pasting measurements showed that the peak viscosity of the control is significantly higher than the samples with date syrup (p date syrup levels. Addition of date syrup increases the solid-like behavior of the gel in reverse order with increased date syrup levels. Low-amylose starch gel used in this study showed minor changes in elastic modulus (G') during one week cold storage indicting that low-amylose rice starch is resistant to retrogradation. Addition of date syrup slightly resulted in increased retrogradation compared to the control.

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

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.

The effect of high hydrostatic pressure treatment on the molecular structure of starches with different amylose content.

Science.gov (United States)

Szwengiel, Artur; Lewandowicz, Grażyna; Górecki, Adrian R; Błaszczak, Wioletta

2018-02-01

The effect of high hydrostatic pressure processing (650MPa/9min) on molecular mass distribution, and hydrodynamic and structural parameters of amylose (maize, sorghum, Hylon VII) and amylopectin (waxy maize, amaranth) starches was studied. The starches were characterized by high-performance size-exclusion chromatography (HPSEC) equipped with static light scattering and refractive index detectors and by Fourier Transform Infrared (FTIR) spectroscopy. Significant changes were observed in molecular mass distribution of pressurized waxy maize starch. Changes in branches/branch frequency, intrinsic viscosity, and radius of gyration were observed for all treated starches. The combination of SEC and FTIR data showed that α-1,6-glycosidic bonds are more frequently split in pressurized amaranth, Hylon VII, and waxy maize starch, while in sorghum and maize starches, the α-1,4 bonds are most commonly split. Our results show that the structural changes found for pressurized starches were more strongly determined by the starch origin than by the processing applied. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

Two unique ligand-binding clamps of Rhizopus oryzae starch binding domain for helical structure disruption of amylose.

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Ting-Ying Jiang

Full Text Available The N-terminal starch binding domain of Rhizopus oryzae glucoamylase (RoSBD has a high binding affinity for raw starch. RoSBD has two ligand-binding sites, each containing a ligand-binding clamp: a polyN clamp residing near binding site I is unique in that it is expressed in only three members of carbohydrate binding module family 21 (CBM21 members, and a Y32/F58 clamp located at binding site II is conserved in several CBMs. Here we characterized different roles of these sites in the binding of insoluble and soluble starches using an amylose-iodine complex assay, atomic force microscopy, isothermal titration calorimetry, site-directed mutagenesis, and structural bioinformatics. RoSBD induced the release of iodine from the amylose helical cavity and disrupted the helical structure of amylose type III, thereby significantly diminishing the thickness and length of the amylose type III fibrils. A point mutation in the critical ligand-binding residues of sites I and II, however, reduced both the binding affinity and amylose helix disruption. This is the first molecular model for structure disruption of the amylose helix by a non-hydrolytic CBM21 member. RoSBD apparently twists the helical amylose strands apart to expose more ligand surface for further SBD binding. Repeating the process triggers the relaxation and unwinding of amylose helices to generate thinner and shorter amylose fibrils, which are more susceptible to hydrolysis by glucoamylase. This model aids in understanding the natural roles of CBMs in protein-glycan interactions and contributes to potential molecular engineering of CBMs.

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.

Identification of genes encoding granule-bound starch synthase involved in amylose metabolism in banana fruit.

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Hongxia Miao

Full Text Available Granule-bound starch synthase (GBSS is responsible for amylose synthesis, but the role of GBSS genes and their encoded proteins remains poorly understood in banana. In this study, amylose content and GBSS activity gradually increased during development of the banana fruit, and decreased during storage of the mature fruit. GBSS protein in banana starch granules was approximately 55.0 kDa. The protein was up-regulated expression during development while it was down-regulated expression during storage. Six genes, designated as MaGBSSI-1, MaGBSSI-2, MaGBSSI-3, MaGBSSI-4, MaGBSSII-1, and MaGBSSII-2, were cloned and characterized from banana fruit. Among the six genes, the expression pattern of MaGBSSI-3 was the most consistent with the changes in amylose content, GBSS enzyme activity, GBSS protein levels, and the quantity or size of starch granules in banana fruit. These results suggest that MaGBSSI-3 might regulate amylose metabolism by affecting the variation of GBSS levels and the quantity or size of starch granules in banana fruit during development or storage.

Identification of Genes Encoding Granule-Bound Starch Synthase Involved in Amylose Metabolism in Banana Fruit

Science.gov (United States)

Liu, Weixin; Xu, Biyu; Jin, Zhiqiang

2014-01-01

Granule-bound starch synthase (GBSS) is responsible for amylose synthesis, but the role of GBSS genes and their encoded proteins remains poorly understood in banana. In this study, amylose content and GBSS activity gradually increased during development of the banana fruit, and decreased during storage of the mature fruit. GBSS protein in banana starch granules was approximately 55.0 kDa. The protein was up-regulated expression during development while it was down-regulated expression during storage. Six genes, designated as MaGBSSI-1, MaGBSSI-2, MaGBSSI-3, MaGBSSI-4, MaGBSSII-1, and MaGBSSII-2, were cloned and characterized from banana fruit. Among the six genes, the expression pattern of MaGBSSI-3 was the most consistent with the changes in amylose content, GBSS enzyme activity, GBSS protein levels, and the quantity or size of starch granules in banana fruit. These results suggest that MaGBSSI-3 might regulate amylose metabolism by affecting the variation of GBSS levels and the quantity or size of starch granules in banana fruit during development or storage. PMID:24505384

Assessment of the influence of amylose-LPC complexation on the extent of wheat starch digestibility by size-exclusion chromatography.

Science.gov (United States)

Ahmadi-Abhari, S; Woortman, A J J; Hamer, R J; Loos, K

2013-12-15

Amylose forms inclusion complexes with lysophosphatidylcholine (LPC), that decrease the susceptibility of amylose to amylase degradation. This study on the influence of complexation on starch susceptibility to amylase explains the nature of this protective effect. Wheat starch suspensions (9% w/w) containing 0.5-5% LPC were subjected to hydrolysis by porcine pancreatic α-amylase at 37 °C for several digestion times. The digesta were analysed by size-exclusion chromatography (SEC). The molar mass distribution was closely dependent on the digestion time and amount of LPC. This study precisely demonstrates the alteration of the digestion profile of starch on a molecular level, influenced by amylose-LPC complexation; however the effect depends on the digestion time. During 15 and 30 min digestion, inclusion complexes not only protect amylopectin in the initial hydrolysis stage, but also demonstrate lower susceptibility of the molecular amylose complexes to amylase hydrolysis. Digestion for 240 min resulted in a lower oligosaccharide peak concentration, in the presence of a high LPC concentration, which is related to less degradation of complexed amylose fraction. Copyright © 2013 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.

The effect of starch amylose content on the morphology andproperties of melt-processed butyl-etherified starch/poly[(butylenesuccinate)-co-adipate] blends

CSIR Research Space (South Africa)

Maubane, Lesego T

2017-01-01

Full Text Available structures. Thermogravimetric analysis revealed that the thermal stability of the blends decreased with increasing starch loading for all starch types with varying amylose content; however, the nature of the starch controlled the mechanical properties...

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

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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.

Preparation of Edible Corn Starch Phosphate with Highly Reactive ...

African Journals Online (AJOL)

1Food & Bioengineering Department, Henan University of Science and Technology, Luoyang, Henan 471003 ... Purpose: To prepare edible corn starch phosphate under optimized experimental conditions. ... In food industry, starch phosphate.

Effect of the addition order and amylose content on mechanical, barrier and structural properties of films made with starch and montmorillonite.

Science.gov (United States)

Romero-Bastida, C A; Bello-Pérez, L A; Velazquez, G; Alvarez-Ramirez, J

2015-01-01

This study considered the effect of amylose content (30% and 70%), montmorillonite (MMT) fraction (5 and 15%) and preparation method on mechanical and barrier properties of starch/clay nanocomposites prepared by casting. In Method 1, (30% w/w) glycerol was incorporated before starch gelatinization and MMT addition, while in Method 2 after gelatinization and MMT addition. Nanocomposites with higher amount of MMT showed the highest tensile strength and Young's modulus for both preparation methods. Method 1 favored nanocomposite properties of films with less amylose content, meanwhile Method 2 favored nanocomposites properties with higher amylose content. Water vapor permeability did not decrease significantly in starch films with different amylose content with the two different preparation methods. X-ray diffraction of the starch films indicated intercalated structures. Higher melting temperature (Tm) was found for nanocomposites with Method 2, indicating more ordered structures. Films with 70% amylose content have higher Tm than films with 30% amylose. Copyright © 2015 Elsevier Ltd. All rights reserved.

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.

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

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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

Microscopic Analysis of Corn Fiber Using Corn Starch- and Cellulose-Specific Molecular Probes

Energy Technology Data Exchange (ETDEWEB)

Porter, S. E.; Donohoe, B. S.; Beery, K. E.; Xu, Q.; Ding, S.-Y.; Vinzant, T. B.; Abbas, C. A.; Himmel, M. E.

2007-09-01

Ethanol is the primary liquid transportation fuel produced from renewable feedstocks in the United States today. The majority of corn grain, the primary feedstock for ethanol production, has been historically processed in wet mills yielding products such as gluten feed, gluten meal, starch, and germ. Starch extracted from the grain is used to produce ethanol in saccharification and fermentation steps; however the extraction of starch is not 100% efficient. To better understand starch extraction during the wet milling process, we have developed fluorescent probes that can be used to visually localize starch and cellulose in samples using confocal microscopy. These probes are based on the binding specificities of two types of carbohydrate binding modules (CBMs), which are small substrate-specific protein domains derived from carbohydrate degrading enzymes. CBMs were fused, using molecular cloning techniques, to a green fluorescent protein (GFP) or to the red fluorescent protein DsRed (RFP). Using these engineered probes, we found that the binding of the starch-specific probe correlates with starch content in corn fiber samples. We also demonstrate that there is starch internally localized in the endosperm that may contribute to the high starch content in corn fiber. We also surprisingly found that the cellulose-specific probe did not bind to most corn fiber samples, but only to corn fiber that had been hydrolyzed using a thermochemical process that removes the residual starch and much of the hemicellulose. Our findings should be of interest to those working to increase the efficiency of the corn grain to ethanol process.

Interaction between amylose and 1-butanol during 1-butanol-hydrochloric acid hydrolysis of normal rice starch.

Science.gov (United States)

Hu, Xiuting; Wei, Benxi; Zhang, Bao; Li, Hongyan; Xu, Xueming; Jin, Zhengyu; Tian, Yaoqi

2013-10-01

The aim of this study was to examine the interaction between amylose and 1-butanol during the 1-butanol-hydrochloric acid (1-butanol-HCl) hydrolysis of normal rice starch. The interaction model between amylose and 1-butanol was proposed using gas chromatography-mass spectrometry (GC-MS), (13)C cross polarization and magic angle spinning NMR analysis ((13)C CP/MAS NMR), differential scanning calorimetry (DSC), and thermalgravimetric analysis (TGA). GC-MS data showed that another form of 1-butanol existed in 1-butanol-HCl-hydrolyzed normal rice starch, except in the form of free molecules absorbed on the starch granules. The signal of 1-butanol-HCl-hydrolyzed starch at 100.1 ppm appeared in the (13)C CP/MAS NMR spectrum, indicating that the amylose-1-butanol complex was formed. DSC and TGA data also demonstrated the formation of the complex, which significantly affected the thermal properties of normal rice starch. These findings revealed that less dextrin with low molecular weight formed might be attributed to resistance of this complex to acid during 1-butanol-HCl hydrolysis. Crown Copyright © 2013. Published by Elsevier B.V. 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...

Physicochemical properties of starches isolated from pumpkin compared with potato and corn starches.

Science.gov (United States)

Przetaczek-Rożnowska, Izabela

2017-08-01

The aim of the study was to characterize the selected physicochemical, thermal and rheological properties of pumpkin starches and compared with the properties of potato and corn starches used as control samples. Pumpkin starches could be used in the food industry as a free gluten starch. Better thermal and rheological properties could contribute to reduce the costs of food production. The syneresis of pumpkin starches was similar to that of potato starch but much lower than that for corn starch. Pasting temperatures of pumpkin starches were lower by 17-21.7°C and their final viscosities were over 1000cP higher than corn paste, but were close to the values obtained for potato starch. The thermodynamic characteristic showed that the transformation temperatures of pumpkin starches were lower than those measured for control starches. A level of retrogradation was much lower in pumpkin starch pastes (32-48%) than was in the case of corn (59%) or potato (77%) starches. The pumpkin starches gels were characterized by a much greater hardness, cohesiveness and chewiness, than potato or corn starches gels. Copyright © 2017 Elsevier B.V. All rights reserved.

Association mapping of starch chain length distribution and amylose content in pea (Pisum sativum L.) using carbohydrate metabolism candidate genes.

Science.gov (United States)

Carpenter, Margaret A; Shaw, Martin; Cooper, Rebecca D; Frew, Tonya J; Butler, Ruth C; Murray, Sarah R; Moya, Leire; Coyne, Clarice J; Timmerman-Vaughan, Gail M

2017-08-01

Although starch consists of large macromolecules composed of glucose units linked by α-1,4-glycosidic linkages with α-1,6-glycosidic branchpoints, variation in starch structural and functional properties is found both within and between species. Interest in starch genetics is based on the importance of starch in food and industrial processes, with the potential of genetics to provide novel starches. The starch metabolic pathway is complex but has been characterized in diverse plant species, including pea. To understand how allelic variation in the pea starch metabolic pathway affects starch structure and percent amylose, partial sequences of 25 candidate genes were characterized for polymorphisms using a panel of 92 diverse pea lines. Variation in the percent amylose composition of extracted seed starch and (amylopectin) chain length distribution, one measure of starch structure, were characterized for these lines. Association mapping was undertaken to identify polymorphisms associated with the variation in starch chain length distribution and percent amylose, using a mixed linear model that incorporated population structure and kinship. Associations were found for polymorphisms in seven candidate genes plus Mendel's r locus (which conditions the round versus wrinkled seed phenotype). The genes with associated polymorphisms are involved in the substrate supply, chain elongation and branching stages of the pea carbohydrate and starch metabolic pathways. The association of polymorphisms in carbohydrate and starch metabolic genes with variation in amylopectin chain length distribution and percent amylose may help to guide manipulation of pea seed starch structural and functional properties through plant breeding.

Effect of amylose:amylopectin ratio and rice bran addition on starch films properties.

Science.gov (United States)

Cano, Amalia; Jiménez, Alberto; Cháfer, Maite; Gónzalez, Chelo; Chiralt, Amparo

2014-10-13

The influence of the amylose:amylopectin ratio on the properties of pea, potato and cassava starch films and the effect of the incorporation of rice bran of two different particle sizes were studied. The structural, mechanical, optical and barrier properties of the films were analyzed after 1 and 5 weeks. The high content of amylose gave rise to stiffer, more resistant to fracture, but less stretchable films, with lower oxygen permeability and greater water binding capacity. Although no changes in the water vapour permeability values of the films were observed during storage, their oxygen permeability decreased. Throughout storage, films became stiffer, more resistant to break, but less stretchable. Rice bran with the smallest particles improved the elastic modulus of the films, especially in high amylose content films, but reduced the film stretchability and its barrier properties, due to the enhancement of the water binding capacity and the introduction of discontinuities. Copyright © 2014 Elsevier Ltd. All rights reserved.

High amylose resistant starch diet ameliorates oxidative stress, inflammation, and progression of chronic kidney disease.

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Nosratola D Vaziri

Full Text Available Inflammation is a major mediator of CKD progression and is partly driven by altered gut microbiome and intestinal barrier disruption, events which are caused by: urea influx in the intestine resulting in dominance of urease-possessing bacteria; disruption of epithelial barrier by urea-derived ammonia leading to endotoxemia and bacterial translocation; and restriction of potassium-rich fruits and vegetables which are common sources of fermentable fiber. Restriction of these foods leads to depletion of bacteria that convert indigestible carbohydrates to short chain fatty acids which are important nutrients for colonocytes and regulatory T lymphocytes. We hypothesized that a high resistant starch diet attenuates CKD progression. Male Sprague Dawley rats were fed a chow containing 0.7% adenine for 2 weeks to induce CKD. Rats were then fed diets supplemented with amylopectin (low-fiber control or high fermentable fiber (amylose maize resistant starch, HAM-RS2 for 3 weeks. CKD rats consuming low fiber diet exhibited reduced creatinine clearance, interstitial fibrosis, inflammation, tubular damage, activation of NFkB, upregulation of pro-inflammatory, pro-oxidant, and pro-fibrotic molecules; impaired Nrf2 activity, down-regulation of antioxidant enzymes, and disruption of colonic epithelial tight junction. The high resistant starch diet significantly attenuated these abnormalities. Thus high resistant starch diet retards CKD progression and attenuates oxidative stress and inflammation in rats. Future studies are needed to explore the impact of HAM-RS2 in CKD patients.

DSC studies of retrogradation and amylose-lipid transition taking place in gamma-irradiated wheat starch

International Nuclear Information System (INIS)

Ciesla, K.; Gluszewski, W.; Eliasson, A.C.

2006-01-01

It has been already shown that degradation resulting from gamma irradiation induces a decrease in order of starch granules and influences gelatinisation taking place during heating of starch and flour suspensions. In presented paper, DSC (differential scanning calorimetry) studies were carried out for wheat starch, non-irradiated and irradiated using doses in the range from 5 to 30 kGy. The influence of the conditions applied during DSC measurements on the possibility to observe differences between the amylose-lipid complex transition and retrogradation taking place in the non-irradiated and particularly irradiated starch samples was checked. The better differentiation between the amylose-lipid complex transition taking place in particular samples accompanied by the better reproducity were obtained in the case of dense suspensions as compared to the watery suspensions as well as during the first analysis performed for the recrystallised gels

Structure of branching enzyme- and amylomaltase modified starch produced from well-defined amylose to amylopectin substrates

DEFF Research Database (Denmark)

Sorndecha, Waraporn; Sagnelli, Domenico; Meier, Sebastian

2016-01-01

by the molar mass rather that the branching density of the glucan per se . Our data demonstrate that a higher amylose content in the substrate starch efficiently produces α-1,6 glucosidic linkages and that the present of amylose generates a higher Μw and more resistant product than amylopectin. The combination...

Barley grain constituents, starch composition, and structure affect starch in vitro enzymatic hydrolysis.

Science.gov (United States)

Asare, Eric K; Jaiswal, Sarita; Maley, Jason; Båga, Monica; Sammynaiken, Ramaswami; Rossnagel, Brian G; Chibbar, Ravindra N

2011-05-11

The relationship between starch physical properties and enzymatic hydrolysis was determined using ten different hulless barley genotypes with variable carbohydrate composition. The ten barley genotypes included one normal starch (CDC McGwire), three increased amylose starches (SH99250, SH99073, and SB94893), and six waxy starches (CDC Alamo, CDC Fibar, CDC Candle, Waxy Betzes, CDC Rattan, and SB94912). Total starch concentration positively influenced thousand grain weight (TGW) (r(2) = 0.70, p starch concentration (r(2) = -0.80, p hydrolysis of pure starch (r(2) = -0.67, p starch concentration (r(2) = 0.46, p starch (RS) in meal and pure starch samples. The rate of starch hydrolysis was high in pure starch samples as compared to meal samples. Enzymatic hydrolysis rate both in meal and pure starch samples followed the order waxy > normal > increased amylose. Rapidly digestible starch (RDS) increased with a decrease in amylose concentration. Atomic force microscopy (AFM) analysis revealed a higher polydispersity index of amylose in CDC McGwire and increased amylose genotypes which could contribute to their reduced enzymatic hydrolysis, compared to waxy starch genotypes. Increased β-glucan and dietary fiber concentration also reduced the enzymatic hydrolysis of meal samples. An average linkage cluster analysis dendrogram revealed that variation in amylose concentration significantly (p starch concentration in meal and pure starch samples. RS is also associated with B-type granules (5-15 μm) and the amylopectin F-III (19-36 DP) fraction. In conclusion, the results suggest that barley genotype SH99250 with less decrease in grain weight in comparison to that of other increased amylose genotypes (SH99073 and SH94893) could be a promising genotype to develop cultivars with increased amylose grain starch without compromising grain weight and yield.

Physicochemical Properties of Gamma-Irradiated Corn Starch

International Nuclear Information System (INIS)

Lee, Y.J.; Lim, S.T.; Kim, S.Y.; Han, S.M.; Kim, H.M.; Kang, I.J.

2006-01-01

Structural modification of corn starch by gamma irradiation was evaluated for under dry conditions at varied intensities from 0 to 40 kGy. Under scanning electron microscopy, the granule shape of corn starch was not significantly affected by the irradiation up to 40 kGy. In addition, X-ray diffraction and melting patterns of the irradiated starches were similar to those of the native starch, indicating that crystalline regions in the starch granules were not changed by irradiation. However, the pattern of gel permeation column chromatography showed a significant increase in partial hydrolysis of gamma irradiated starch samples

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.

Substituted amylose matrices for oral drug delivery

International Nuclear Information System (INIS)

Moghadam, S H; Wang, H W; El-Leithy, E Saddar; Chebli, C; Cartilier, L

2007-01-01

High amylose corn starch was used to obtain substituted amylose (SA) polymers by chemically modifying hydroxyl groups by an etherification process using 1,2-epoxypropanol. Tablets for drug-controlled release were prepared by direct compression and their release properties assessed by an in vitro dissolution test (USP XXIII no 2). The polymer swelling was characterized by measuring gravimetrically the water uptake ability of polymer tablets. SA hydrophilic matrix tablets present sequentially a burst effect, typical of hydrophilic matrices, and a near constant release, typical of reservoir systems. After the burst effect, surface pores disappear progressively by molecular association of amylose chains; this allows the creation of a polymer layer acting as a diffusion barrier and explains the peculiar behaviour of SA polymers. Several formulation parameters such as compression force, drug loading, tablet weight and insoluble diluent concentration were investigated. On the other hand, tablet thickness, scanning electron microscope analysis and mercury intrusion porosimetry showed that the high crushing strength values observed for SA tablets were due to an unusual melting process occurring during tabletting although the tablet external layer went only through densification, deformation and partial melting. In contrast, HPMC tablets did not show any traces of a melting process

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.

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

Directory of Open Access Journals (Sweden)

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

High surface area starch products as filler-binder in direct compression tablets

NARCIS (Netherlands)

te Wierik, G.HP; Ramaker, J.S; Eissens, A.C; Bergsma, J; Arends-Scholte, A.W.; Lerk, C.F

Amylodextrin and modified starch products were prepared from amylose-free starches and from (amylose containing) potato starch by enzymatic degradation, followed by precipitation and filtration. The intermediate retrograded starch products were dehydrated by drying at room temperature or washing

Poly(vinyl alcohol) composite films with high percent elongation prepared from amylose-fatty ammonium salt inclusion complexes

Science.gov (United States)

Amylose inclusion complexes prepared from cationic fatty ammonium salts and jet-cooked high amylose starch were combined with poly(vinyl alcohol) (PVOH) to form glycerol-plasticized films. Their tensile properties were compared with similar films prepared previously with analogous anionic fatty acid...

Rheological properties of wheat starch influenced by amylose-lysophosphatidylcholine complexation at different gelation phases

NARCIS (Netherlands)

Ahmadiabhari, Salomeh; Woortman, Albert; Hamer, Rob; Loos, Katja

2015-01-01

Amylose is able to form helical inclusion complexes with lysophosphatidylcholine (LPC). This complexation influences the functional and rheological properties of wheat starch; however it is well known that the formation of these complexes lead the starchy systems to a slower enzymatic hydrolysis.

Rheological properties of wheat starch influenced by amylose-lysophosphatidylcholine complexation at different gelation phases

NARCIS (Netherlands)

Ahmadi-Abhari, S.; Woortman, A.J.J.; Hamer, R.J.; Loos, K.

2015-01-01

Amylose is able to form helical inclusion complexes with lysophosphatidylcholine (LPC). This complexation influences the functional and rheological properties of wheat starch; however it is well known that the formation of these complexes lead the starchy systems to a slower enzymatic hydrolysis.

Effect of starch types on properties of biodegradable polymer based on thermoplastic starch process by injection molding technique

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Yossathorn Tanetrungroj

2015-04-01

Full Text Available In this study effects of different starch types on the properties of biodegradable polymer based on thermoplastic starch (TPS were investigated. Different types of starch containing different contents of amylose and amylopectin were used, i.e. cassava starch, mungbean starch, and arrowroot starch. The TPS polymers were compounded and shaped using an internal mixer and an injection molding machine, respectively. It was found that the amount of amylose and amylopectin contents on native starch influence the properties of the TPS polymer. A high amylose starch of TPMS led to higher strength, hardness, degree of crystallization than the high amylopectin starch of TPCS. In addition, function group analysis by Fourier transforms infrared spectrophotometer, water absorption, and biodegradation by soil burial test were also examined.

Comparison of gamma radiation effects on natural corn and potato starches and modified cassava starch

Science.gov (United States)

Teixeira, Bruna S.; Garcia, Rafael H. L.; Takinami, Patricia Y. I.; del Mastro, Nelida L.

2018-01-01

The objective of this work was to evaluate the effect of irradiation treatment on physicochemical properties of three natural polymers, i.e. native potato and corn starches and a typical Brazilian product, cassava starch modified through fermentation -sour cassava- and also to prepare composite hydrocolloid films based on them. Starches were irradiated in a 60Co irradiation chamber in doses up to 15 kGy, dose rate about 1 kGy/h. Differences were found in granule size distribution upon irradiation, mainly for corn and cassava starch but radiation did not cause significant changes in granule morphology. The viscosity of the potato, corn and cassava starches hydrogels decreased as a function of absorbed dose. Comparing non-irradiated and irradiated starches, changes in the Fourier transform infrared (FTIR) spectra in the 2000-1500 cm-1 region for potato and corn starches were observed but not for the cassava starch. Maximum rupture force of the starch-based films was affected differently for each starch type; color analysis showed that doses of 15 kGy promoted a slight rise in the parameter b* (yellow color) while the parameter L* (lightness) was not significantly affected; X-ray diffraction patterns remained almost unchanged by irradiation.

Amylose content decreases during tuber development in potato.

Science.gov (United States)

Jansky, Shelley; Fajardo, Diego

2016-10-01

Potato starch is composed primarily of amylopectin and amylose in an approximately 3:1 ratio. Amylose is considered to be nutritionally desirable in North American and European markets, so there is interest in finding strategies to increase the amylose content of potato starch. There is also interest in marketing 'baby' potatoes, which are harvested when they are physiologically immature. This study was carried out to determine weekly changes in amylose content in potato tubers of 11 North American cultivars during the growing season. The trial was repeated across 3 years. We determined that amylose content is highest early and it decreases in a linear fashion as the growing season progresses. Mean amylose content across cultivars and years declined from 30.0% in late June to 26.8% in late August. The rate of decrease varied across years, with slopes of linear regression plots ranging from -0.17 in 2012 to -0.74 in 2011. Amylose content in tuber starch varied among cultivars, with the highest levels observed in Ranger Russet (30.7%) and White Pearl (31.6%); it was lowest in Kennebec (25.7%) and Langlade (25.6%). This study adds to a growing body of literature on the nutritional value of immature potato tubers. In addition to having higher levels of some phytonutrients, as reported in other studies, immature tubers have a higher proportion of amylose in the starch. This is nutritionally desirable in affluent regions where high fiber content is more important than calories from carbohydrates. Published 2016. This article is a U.S. Government work and is in the public domain in the USA. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

AFM images of complexes between amylose and Aspergillus niger glucoamylase mutants, native and mutant starch binding domains: a model for the action of glucoamylase

DEFF Research Database (Denmark)

Morris, V. M.; Gunning, A. P.; Faults, C. B.

2005-01-01

Atomic force microscopy has been used to investigate the complexes formed between high molecular weight amylose chains and Aspergillus niger glucoamylase mutants (E400Q and W52F), wild-type A. niger starch binding domains (SBDS), and mutant SBDs (W563K and W590K) lacking either of the two starch...

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

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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

Growth, Feed Utilization and Blood Metabolic Responses to Different Amylose-amylopectin Ratio Fed Diets in Tilapia (

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Meng-Yao Chen

2013-08-01

Full Text Available A feeding trial was conducted in tilapia to determine the growth performance, nutrient digestibility, digestive enzymes, and postprandial blood metabolites in response to different dietary amylose-amylopectin ratios. Five isonitrogenous and isolipidic diets containing an equal starch level with different amylose-amylopectin ratios of 0.11 (diet 1, 0.24 (diet 2, 0.47 (diet 3, 0.76 (diet 4 and 0.98 (diet 5 were formulated using high-amylose corn starch (as the amylose source and waxy rice (as the amylopectin source. Each diet was hand-fed to six tanks of 15 fish each, three times a day over a 6-wk period. After the growth trial, a postprandial blood metabolic test was carried out. Fish fed diet 2 exhibited the highest percent weight gain and feed efficiency and protein efficiency ratio, whereas fish fed with diet 5 showed the lowest growth and feed utilization among treatments. The digestibility for starch in fish fed diet 1 and 2 was higher than those in fish fed with other diets (p<0.05. The highest activities for protease, lipase and amylase were found in fish fed the diet 2, diet 1, and diet 1 respectively among dietary treatments, while the lowest values for these indexes were observed in fish fed the diet 3, diet 5 and diet 4, respectively. The liver glycogen concentrations in fish fed diets 4 and 5 were found higher than in fish fed other diets (p<0.05. The feeding rate, hepatosomatic index, condition factor, and plasma parmeters (glucose, triglyceride, total cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol did not differ across treatments. In terms of postprandial blood responses, peak blood glucose and triglycerides were lower after 3 or 6 h in the fish fed with diets 3–5 than in the fish fed diet 1, but delayed peak blood total amino acid time was observed in fish fed with the diets 1 or 2. The lowest peak values for each of the three blood metabolites were observed in fish fed diet 5. The

Increasing the amylose content of durum wheat through silencing of the SBEIIa genes

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Masci Stefania

2010-07-01

Full Text Available Abstract Background High amylose starch has attracted particular interest because of its correlation with the amount of Resistant Starch (RS in food. RS plays a role similar to fibre with beneficial effects for human health, providing protection from several diseases such as colon cancer, diabetes, obesity, osteoporosis and cardiovascular diseases. Amylose content can be modified by a targeted manipulation of the starch biosynthetic pathway. In particular, the inactivation of the enzymes involved in amylopectin synthesis can lead to the increase of amylose content. In this work, genes encoding starch branching enzymes of class II (SBEIIa were silenced using the RNA interference (RNAi technique in two cultivars of durum wheat, using two different methods of transformation (biolistic and Agrobacterium. Expression of RNAi transcripts was targeted to the seed endosperm using a tissue-specific promoter. Results Amylose content was markedly increased in the durum wheat transgenic lines exhibiting SBEIIa gene silencing. Moreover the starch granules in these lines were deformed, possessing an irregular and deflated shape and being smaller than those present in the untransformed controls. Two novel granule bound proteins, identified by SDS-PAGE in SBEIIa RNAi lines, were investigated by mass spectrometry and shown to have strong homologies to the waxy proteins. RVA analysis showed new pasting properties associated with high amylose lines in comparison with untransformed controls. Finally, pleiotropic effects on other starch genes were found by semi-quantitative and Real-Time reverse transcription-polymerase chain reaction (RT-PCR. Conclusion We have found that the silencing of SBEIIa genes in durum wheat causes obvious alterations in granule morphology and starch composition, leading to high amylose wheat. Results obtained with two different methods of transformation and in two durum wheat cultivars were comparable.

Preparation and In vitro Digestibility of Corn Starch Phosphodiester ...

African Journals Online (AJOL)

Purpose: To optimize the process conditions and analyze in vitro digestibility of corn starch phosphodiester prepared by sodium trimetaphosphate (STMP). Methods: By using response surface method, the effects of STMP concentration, pH, esterification temperature, and urea addition on digestion resistance of corn starch ...

DSC Studies of Retrogradation and Amylose-Lipid Complex Transition Taking Place in Gamma Irradiated Wheat Starch

International Nuclear Information System (INIS)

Ciesla, K.

2006-01-01

Degradation resulting from gamma irradiation induces decrease in order of starch granules and influences the processes occurring in starch-water system. Differential scanning calorimetry (DSC) was applied at present for studying the effect of radiation with doses of 5 - 30 kGy on amylose-lipid complex transition and retrogradation occurring in wheat starch gels. Influence of the conditions applied during DSC measurements and intermediate storage was tested on the possibility to observe radiation effect. Wheat starch was irradiated with 60 C o gamma rays in a gamma cell Issledovatiel placed in the Department of Radiation Chemistry, INCT. DSC measurements were performed for ca. 50% and ca. 20% gels during heating - cooling - heating cycles (up to 3 cycles) in the temperature range 10 - 150 degree at heating and cooling rates of 10, 5 and 2.5 degree min - 1. The Seiko DSC 6200 calorimeter was used. Decrease in amylose-lipid complex transition temperature was found already after irradiation of wheat starch with a dose of 5 kGy showing modificatin of the complex structure. The differences between the irradiated and the non-irradiated samples became the easier seen in the every foregoing heating or cooling cycle as compared to the preceeding one. It is because that thermal treatment causes decrease of transition temperature in all the irradiated samples, with no effect or increase of that temperature observed in the non-irradiated ones. Irradiation hinders retrogradation taking place in ca. 50% gels but facilitates retrogradation occurring in ca. 20 % gels. Moreover, the expanded differences between the amylose-lipid complex formed in the irradiated and non-irradiated gels result due to their recrystallisation. Storage of the gels induces decrease in the temperature of the complex transition as compared to the last cycle of the first analysis. That decrease was, however, more significant in the case of all the irradiated samples than in the case of the initial sample. In

Genetic Engineering of Cereal Grains with Starch Consisting of More Than 99% Amylase

DEFF Research Database (Denmark)

Hebelstrup, Kim; Carciofi, Massimiliano; Blennow, Andreas

2013-01-01

Numerous textbooks tell us that plant starches are a mix of two starch types: amylopectin and amylose. We recently succeeded in engineering a cereal crop – a barley line – producing grain starch consisting of more than 99% amylose1. This amylose-only starch contains a high residual fraction...

The effects of amylose and starch phosphate on starch gel retrogradation studied by low-field 1H NMR relaxometry

DEFF Research Database (Denmark)

Thygesen, Lisbeth Garbrecht; Blennow, A.; Engelsen, S. B.

2003-01-01

Low-field Nuclear Magnetic Resonance (23 MHz) was used to study the effects of the degree of phosphorylation, the amylose content and the amylopectin chain length distribution on gel retrogradation for a set of 26 starches, six of which were of crystal polymorph type A, 18 of type B and two of type......) relaxation curves from the two measurements (day 1 and day 7) could be used as a simple, illustrative way of describing the retrogradation. Three different behaviours were identified: One group of samples (mostly potato starches) slowly changed from a soft to a more rigid gel from day 1 to 7. A second group...

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.

Design starch: stochastic modeling of starch granule biogenesis.

Science.gov (United States)

Raguin, Adélaïde; Ebenhöh, Oliver

2017-08-15

Starch is the most widespread and abundant storage carbohydrate in plants and the main source of carbohydrate in the human diet. Owing to its remarkable properties and commercial applications, starch is still of growing interest. Its unique granular structure made of intercalated layers of amylopectin and amylose has been unraveled thanks to recent progress in microscopic imaging, but the origin of such periodicity is still under debate. Both amylose and amylopectin are made of linear chains of α-1,4-bound glucose residues, with branch points formed by α-1,6 linkages. The net difference in the distribution of chain lengths and the branching pattern of amylose (mainly linear), compared with amylopectin (racemose structure), leads to different physico-chemical properties. Amylose is an amorphous and soluble polysaccharide, whereas amylopectin is insoluble and exhibits a highly organized structure of densely packed double helices formed between neighboring linear chains. Contrarily to starch degradation that has been investigated since the early 20th century, starch production is still poorly understood. Most enzymes involved in starch growth (elongation, branching, debranching, and partial hydrolysis) are now identified. However, their specific action, their interplay (cooperative or competitive), and their kinetic properties are still largely unknown. After reviewing recent results on starch structure and starch growth and degradation enzymatic activity, we discuss recent results and current challenges for growing polysaccharides on granular surface. Finally, we highlight the importance of novel stochastic models to support the analysis of recent and complex experimental results, and to address how macroscopic properties emerge from enzymatic activity and structural rearrangements. © 2017 The Author(s).

Design starch: stochastic modeling of starch granule biogenesis

Science.gov (United States)

Ebenhöh, Oliver

2017-01-01

Starch is the most widespread and abundant storage carbohydrate in plants and the main source of carbohydrate in the human diet. Owing to its remarkable properties and commercial applications, starch is still of growing interest. Its unique granular structure made of intercalated layers of amylopectin and amylose has been unraveled thanks to recent progress in microscopic imaging, but the origin of such periodicity is still under debate. Both amylose and amylopectin are made of linear chains of α-1,4-bound glucose residues, with branch points formed by α-1,6 linkages. The net difference in the distribution of chain lengths and the branching pattern of amylose (mainly linear), compared with amylopectin (racemose structure), leads to different physico-chemical properties. Amylose is an amorphous and soluble polysaccharide, whereas amylopectin is insoluble and exhibits a highly organized structure of densely packed double helices formed between neighboring linear chains. Contrarily to starch degradation that has been investigated since the early 20th century, starch production is still poorly understood. Most enzymes involved in starch growth (elongation, branching, debranching, and partial hydrolysis) are now identified. However, their specific action, their interplay (cooperative or competitive), and their kinetic properties are still largely unknown. After reviewing recent results on starch structure and starch growth and degradation enzymatic activity, we discuss recent results and current challenges for growing polysaccharides on granular surface. Finally, we highlight the importance of novel stochastic models to support the analysis of recent and complex experimental results, and to address how macroscopic properties emerge from enzymatic activity and structural rearrangements. PMID:28673938

Degradation of the starch components amylopectin and amylose by barley α-amylase 1: Role of surface binding site 2

DEFF Research Database (Denmark)

Nielsen, Jonas Willum; Kramhøft, Birte; Bozonnet, Sophie

2012-01-01

Barley α-amylase isozyme 1 (AMY1, EC 3.2.1.1) contains two surface binding sites, SBS1 and SBS2, involved in the degradation of starch granules. The distinct role of SBS1 and SBS2 remains to be fully understood. Mutational analysis of Tyr-380 situated at SBS2 previously revealed that Tyr-380...... is required for binding of the amylose helix mimic, β-cyclodextrin. Also, mutant enzymes altered at position 380 displayed reduced binding to starch granules. Similarly, binding of wild type AMY1 to starch granules was suppressed in the presence of β-cyclodextrin. We investigated the role of SBS2 by comparing...... kinetic properties of the wild type AMY1 and the Y380A mutant enzyme in hydrolysis of amylopectin, amylose and β-limit dextrin, and the inhibition by β-cyclodextrin. Progress curves of the release of reducing ends revealed a bi-exponential hydrolysis of amylopectin and β-limit dextrin, whereas hydrolysis...

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

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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.

The improvement of corn starch isolation process by gamma irradiation

International Nuclear Information System (INIS)

Byun, M.W.; Kang, I.J.; Kwon, J.H.; Lee, S.J.; Kim, S.K.

1995-01-01

Gamma irradiation was applied to non-glutinous and glutinous corns for improving starch isolation process. No significant changes in proximate composition of corn grains were observed by gamma irradiation. Irradiation at 1 and 5 kGy was effective for sterilizing all contaminated microorganisms of non-glutinous and glutinous corns, respectively. The moisture-uptake rate constants were increased in proportional to the steeping temperature and applied irradiation dose level. The irradiation efficacy on water absorption properties was also recognized in the corns stored for six months at room temperature. The combined use of gamma irradiation with sulfur dioxide solution was very effective for reducing steeping time. The starch yield gradually increased as irradiation dose levels increased. At 2 kGy, the sarch yield of non-glutinous and glutinous corns increased by 38% and 27%, respectively. No significant difference in Hunter's color value was observed between the starches isolated from nonirradiated and irradiated corn grains

Biosysthesis of Corn Starch Palmitate by Lipase Novozym 435

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Kai Lin

2012-06-01

Full Text Available Esterification of starch was carried out to expand the usefulness of starch for a myriad of industrial applications. Lipase B from Candida antarctica, immobilized on macroporous acrylic resin (Novozym 435, was used for starch esterification in two reaction systems: micro-solvent system and solvent-free system. The esterification of corn starch with palmitic acid in the solvent-free system and micro-solvent system gave a degree of substitution (DS of 1.04 and 0.0072 respectively. Esterification of corn starch with palmitic acid was confirmed by UV spectroscopy and IR spectroscopy. The results of emulsifying property analysis showed that the starch palmitate with higher DS contributes to the higher emulsifying property (67.6% and emulsion stability (79.6% than the native starch (5.3% and 3.9%. Modified starch obtained by esterification that possesses emulsifying properties and has long chain fatty acids, like palmitic acid, has been widely used in the food, pharmaceutical and biomedical applications industries.

Mid-infrared spectroscopy and chemometrics in corn starch classification

Science.gov (United States)

Dupuy, N.; Wojciechowski, C.; Ta, C. D.; Huvenne, J. P.; Legrand, P.

1997-06-01

The authentication of food is a very important issue for both the consumer and the food industry at all levels of the food chain from raw materials to finished products. Corn starch can be used in a wide variety of food preparations such as bakery cream fillings, sauces, salad dressings, frozen foods etc. Many modifications are made to corn starch in connection with its use in agrofood. The value of the product increases with the degree of modification. Some chemical and physical tests have been devised to solve the problem of identifying these modifications but all the methods are time consuming and require skilled operators. We separate corn starches into groups related to their modification on the basis of the infrared spectra.

Starch Spherulites Prepared by a Combination of Enzymatic and Acid Hydrolysis of Normal Corn Starch.

Science.gov (United States)

Shang, Yaqian; Chao, Chen; Yu, Jinglin; Copeland, Les; Wang, Shuo; Wang, Shujun

2018-06-13

This paper describes a new method to prepare spherulites from normal corn starch by a combination of enzymatic (mixtures of α-amylase and amyloglucosidase) and acid hydrolysis followed by recrystallization of the hydrolyzed products. The resulting spherulites contained a higher proportion of chains with a degree of polymerization (DP) of 6-12 and a lower proportion of chains with DP of 25-36, compared to those of native starch. The spherulites had an even particle size of about 2 μm and a typical B-type crystallinity. The amounts of long- and short-range molecular order of double helices in starch spherulites were larger, but the quality of starch crystallites was poorer, compared to that of native starch. This study showed an efficient method for preparing starch spherulites with uniform granule morphology and small particle size from normal corn starch. The ratios of α-amylase and amyloglucosidase in enzymatic hydrolysis had little effect on the structure of the starch spherulites.

Mutations in durum wheat SBEII genes conferring increased amylose and resistant starch affect grain yield components, semolina and pasta quality and fermentation responses in rats

Science.gov (United States)

Increased amylose in wheat (Triticum spp.) starch is associated with increased resistant starch, a fermentable dietary fiber. Fermentation of resistant starch in the large intestine produces short-chain fatty acids that provide human health benefits. Since wheat foods are an important component of t...

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.

Starch Bioengineering in Barley

DEFF Research Database (Denmark)

Shaik, Shahnoor Sultana

, the effects of engineering high levels of phosphate and amylose content on starch physico-chemical properties were evaluated by various biochemical and morphological studies. As a result, a substantial increase of 10-fold phosphate content and ~99% amylose content with high-resistant starch was observed...... in storage reserve accumulation, metabolite accumulation in AO but no significant differences were observed in HP compared to WT. Scanning electron microscopy and confocal microscopy revealed the details in topography and internal structures of the starch granules in these lines. The results demonstrated......Starch represents the most important carbohydrate used for food and feed purposes. Increasingly, it is also used as a renewable raw material, as a source of biofuel, and for many different industrial applications. Progress in understanding starch biosynthesis, and investigations of the genes...

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.

Discrete forms of amylose are synthesized by isoforms of GBSSI in pea

NARCIS (Netherlands)

Edwards, A.; Vincken, J.P.; Suurs, L.C.J.M.; Visser, R.G.F.; Zeeman, S.; Smith, A.; Martin, C.

2002-01-01

Amyloses with distinct molecular masses are found in the starch of pea embryos compared with the starch of pea leaves. In pea embryos, a granule-bound starch synthase protein (GBSSIa) is required for the synthesis of a significant portion of the amylose. However, this protein seems to be

Deficiencies in both starch synthase IIIa and branching enzyme IIb lead to a significant increase in amylose in SSIIa-inactive japonica rice seeds.

Science.gov (United States)

Asai, Hiroki; Abe, Natsuko; Matsushima, Ryo; Crofts, Naoko; Oitome, Naoko F; Nakamura, Yasunori; Fujita, Naoko

2014-10-01

Starch synthase (SS) IIIa has the second highest activity of the total soluble SS activity in developing rice endosperm. Branching enzyme (BE) IIb is the major BE isozyme, and is strongly expressed in developing rice endosperm. A mutant (ss3a/be2b) was generated from wild-type japonica rice which lacks SSIIa activity. The seed weight of ss3a/be2b was 74-94% of that of the wild type, whereas the be2b seed weight was 59-73% of that of the wild type. There were significantly fewer amylopectin short chains [degree of polymerization (DP) ≤13] in ss3a/be2b compared with the wild type. In contrast, the amount of long chains (DP ≥25) connecting clusters of amylopectin in ss3a/be2b was higher than in the wild type and lower than in be2b. The apparent amylose content of ss3a/be2b was 45%, which was >1.5 times greater than that of either ss3a or be2b. Both SSIIIa and BEIIb deficiencies led to higher activity of ADP-glucose pyrophosphorylase (AGPase) and granule-bound starch synthase I (GBSSI), which partly explains the high amylose content in the ss3a/be2b endosperm. The percentage apparent amylose content of ss3a and ss3a/be2b at 10 days after flowering (DAF) was higher than that of the wild type and be2b. At 20 DAF, amylopectin biosynthesis in be2b and ss3a/be2b was not observed, whereas amylose biosynthesis in these lines was accelerated at 30 DAF. These data suggest that the high amylose content in the ss3a/be2b mutant results from higher amylose biosynthesis at two stages, up to 20 DAF and from 30 DAF to maturity. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Improved amylose content of rice (IR72) induced through gamma radiation

International Nuclear Information System (INIS)

Barrida, Adelaida C.; Rivera, Faye G.; Manrique, Mary Jayne C.; Dimaano, Arvin O.; Costimiano, Eduardo C.

2015-01-01

In general grain quality and quality preferences vary across rice growing countries and regions. Filipinos preferres translucent, well milled, long grain rice with aroma and minimal broken grains which is soft after cooling. The amylose content of rice starch is a major eating quality factor. The aim of this study is to develop rice mutants with good eating quality and low to intermediate amylose content through induced mutation using gamma radiation. Low to intermediate amylose content in rice were identified and selected among the advance generation lines irradiated with 200 and 300Gy dose of gamma radiation. Screening was done using qualitative method (Iodine staining method). Selected lines were analyzed quantitatively, to determine the percent amylose content. Percent amylose were group to several categories where; 0-6% is waxy, 6-12% is very low, 12-18% is low, 18-24% is intermediate and >25% is high. Results were further confirmed using molecular marker technique by looking at the waxy gene which code for granule bound starch synthase I (GBSSI) and controls amylose content in rice. Among the 30 lines selcted and anaylzes, 2 lines were confirmed to have a gene base mutation with a low to intermediate amylose content. Thus, induced mutation using gamma radiation has successfully improved amylose content in rice (IR72). (author)

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.

VARIABILITY OF AMYLOSE AND AMYLOPECTIN IN WINTER WHEAT AND SELECTION FOR SPECIAL PURPOSES

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Nikolina Weg Krstičević

2015-06-01

Full Text Available The aim of this study was to investigate the variability of amylose and amylopectin in 24 Croatian and six foreign winter wheat varieties and to detect the potential of these varieties for special purposes. Starch composition analysis was based on the separation of amylose and amylopectin and the determination of their amounts and ratios. Analysis of the amount of amylose and amylopectin determined statistically highly significant differences between the varieties. The tested varieties are mostly bread wheat of different quality which have the usual content of amylose and amylopectin. Some varieties were identified among them with high amylopectin and low amylose content and one variety with high amylose content. They have the potential in future breeding programs and selection for special purposes.

Production of glutinous rice flour from broken rice via ultrasonic assisted extraction of amylose.

Science.gov (United States)

Setyawati, Yohana Dwi; Ahsan, Sitti Faika; Ong, Lu Ki; Soetaredjo, Felycia Edi; Ismadji, Suryadi; Ju, Yi-Hsu

2016-07-15

In this study, a modified aqueous leaching method by complex formation of amylose with glycerol was employed for reducing the amylose content of starch in broken white rice to less than 2%, so that the resulting starch can be classified to that of glutinous rice flour. By employing ultrasonication in alkaline condition, extraction of amylose could be performed by washing at lower temperature in shorter time compared to the existing aqueous leaching method. The effects of glycerol concentration, alkali concentration, ultrasonication and treatment time on the amylose content of the treated starch were systematically investigated. Under optimum condition, amylose content of broken white rice starch can be reduced from 27.27% to 1.43% with a yield of 80.42%. The changes in the physicochemical properties of the rice flour before and after treatment were studied. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Pasting and Gel Textural Properties of Corn Starch in Glucose, Fructose and Maltose Syrup

OpenAIRE

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...

DEVELOPMENT OF ADHESIVE TO THE BASIS OF CORN AND CASSAVA STARCH

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Rosane Furtado Fabrício

2014-05-01

Full Text Available Corn and native cassava starch were modified by oxidation and acid hydrolysis, aiming to develop paper and paperboard stickers. The oxidation was made with Sodium hypochlorite (NaOCl in two distinct concentrations of active chloride which is present on oxidizing agent solution. The synthesis resulting products were used to make stickers and they were compared to corn and cassava starch based stickers without any modification, as well as commercial stickers based on polyvinyl acetate (PVA. Two different methodologies were tested using acid hydrolysis to modify corn and cassava starch, both using phosphoric acid (H3PO4 in order to obtain dextrin and subsequently use it in the production of stickers and also comparing them to petrochemical-based commercial stickers. Considering the different starch modifications methods (oxidation and acid hydrolysis, stickers based on renewable raw material were obtained, which combine biodegradability, low costs and availability.

Thermal Properties of Starch From New Corn Lines as Impacted by Environment and During Line Development

Energy Technology Data Exchange (ETDEWEB)

Lenihan, Elizabeth M [Iowa State Univ., Ames, IA (United States)

2003-01-01

The objectives of this research were to further characterize exotic by adapted corn inbreds by studying the impact of environment on their starch thermal properties, and investigating the development of starch thermal properties during kernel maturation by using differential scanning calorimetry (DSC). A method to expedite identification of unusual starch thermal traits was investigated by examining five corn kernels at a time, instead of one kernel, which the previous screening methods used. Corn lines with known thermal functions were blended with background starch (control) in ratios of unique starch to control starch, and analyzed by using DSC. Control starch was representative of typical corn starch. The values for each ratio within a mutant type were unique (α < 0.01) for most DSC measurements. These results supported the five-kernel method for rapidly screening large amounts of corn germplasm to identify unusual starch traits. The effects of 5 growing locations on starch thermal properties from exotic by adapted corn and Corn Belt lines were studied using DSC. The warmest location, Missouri, generally produced starch with greater gelatinization onset temperature (T_oG), narrower range of gelatinization (R_G), and greater enthalpy of gelatinization (ΔH_G). The coolest location, Illinois, generally resulted in starch with lower T_oG, wider R_G, and lower ΔH_G. Starch from the Ames 1 farm had thermal properties similar to those of Illinois, whereas starch from the Ames 2 farm had thermal properties similar to those of Missouri. The temperature at Ames 2 may have been warmer since it was located near a river; however, soil type and quality also were different. Final corn starch structure and function change during development and maturity. Thus, the changes in starch thermal properties during 5 stages of endosperm development from exotic by adapted corn and Corn Belt lines at two locations were

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.

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.

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

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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

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.

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)

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.

Extraction and properties of starches from the non-traditional vegetables Yam and Taro

Energy Technology Data Exchange (ETDEWEB)

Andrade, Luan Alberto; Barbosa, Natalia Alves; Pereira, Joelma, E-mail: luandrade87@yahoo.com.br [Universidade Federal de Lavras (UFLA), Lavras, MG (Brazil)

2017-04-15

The objective of this study was to assess the chemical, physical, morphological, crystalline and thermal properties of starch from two non-traditional vegetables, yam and taro. The analyses included proximate composition percent, amylose and mineral content, water absorption capacity, absolute density, morphological properties, X-ray diffractometry, thermal properties, pasting properties and infrared spectrum. The extracted starch exhibited a high purity level with low lipid, fiber and ash contents. The electron micrographs suggested that the taro starch granules were smaller than the yam starch granules. The results for the experimental conditions used in this study indicated that the studied starches differed, especially the amylose content, granule size and crystallinity degree and the pattern of the starches. Due to the high amylose content of yam starch, this type of starch can be used for film preparation, whereas the taro starch can be used as a fat substitute due to its small granule size. (author)

The effect of temperature and time on the formation of amylose- lysophosphatidylcholine inclusion complexes

NARCIS (Netherlands)

Ahmadiabhari, Salomeh; Woortman, Albert J. J.; Oudhuis, A. A. C. M. (Lizette); Hamer, Rob J.; Loos, Katja

The formation of amylose inclusion complexes could help to decrease the susceptibility of starch granules against amylase digestion. We studied the formation of amylose-lysophosphatidylcholine (LPC) inclusion complexes at temperatures at and below the gelatinization temperature of starch, using DSC,

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.

Autoclave and beta-amylolysis lead to reduced in vitro digestibility of starch.

Science.gov (United States)

Hickman, B Elliot; Janaswamy, Srinivas; Yao, Yuan

2009-08-12

In this study, a combination of autoclave and beta-amylolysis was used to modulate the digestibility of normal corn starch (NCS) and wheat starch (WS). The modification procedure comprised three cycles of autoclave at 35% moisture content and 121 degrees C, beta-amylolysis, and one additional cycle of autoclave. Starch materials were sampled at each stage and characterized. The fine structure of starch was determined using high-performance size-exclusion chromatography, the micromorphology of starch dispersion was imaged using cryo-SEM, the crystalline pattern was evaluated using wide-angle X-ray powder diffraction, and the digestibility was measured using Englyst assay. After beta-amylolysis, amylose was enriched (from 25.4 to 33.2% for NCS and from 27.5 to 32.8% for WS) and the branch density was increased (from 5.2 to 7.7% for NCS and from 5.3 to 7.9% for WS). Cryo-SEM images showed that the autoclave treatment led to the formation of a low-swelling, high-density gel network, whereas beta-amylolysis nearly demolished the network structure. The loss of A-type crystalline structure and the formation of B- and V-type structures resulted from autoclave, which suggests the formation of amylose-based ordered structure. Englyst assay indicated that, due to beta-amylolysis, the resistant starch (RS) content was increased to 30 from 11% of native NCS and to 23 from 9% of native WS. In contrast, autoclave showed only minor impact on RS levels. The increase of RS observed in this study is associated with enhanced branch density, which is different from the four types of RS commonly defined.

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

High Amylose White Rice Reduces Post-Prandial Glycemic Response but Not Appetite in Humans

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Alison M. Zenel

2015-07-01

Full Text Available The present study compared the effects of three rice cultivars on postprandial glycemic control and appetite. A single-blind, randomized, crossover clinical trial was performed with 18 healthy subjects, nine males and nine females. Three treatments were administered at three separate study visits: commercially available conventional white rice (short grain, specialty high amylose white rice 1 (Dixiebelle, and specialty high amylose white rice 2 (Rondo. Postprandial capillary blood glucose, venous blood glucose and insulin measurements, and appetite visual analog scale (VAS surveys were done over the course of two hours. The capillary blood glucose concentrations were significantly lower for Rondo compared to short grain rice at 30 min, and for Dixiebelle and Rondo compared to short grain rice at 45, 60, and 120 min. Capillary blood glucose area under the curve (AUC was significantly lower for Dixiebelle and Rondo compared to short grain rice. Subjects were significantly more hungry at 30 min after Dixiebelle intake than Rondo intake, but there were no other significant effects in appetite ratings. The present study determined that intake of high amylose rice with resistant starch (RS can attenuate postprandial blood glucose and insulin response in comparison to short grain rice.

EVALUACIÓN DE LAS PROPIEDADES QUÍMICAS Y FUNCIONALES DEL ALMIDÓN NATIVO DE ÑAME CONGO ( Dioscorea bulbifera L. PARA PREDECIR SUS POSIBLES USOS TECNOLÓGICOS I EVALUATION OF CHEMICAL AND FUNCTIONAL PROPERTIES OF NATIVE STARCH OF CONGO YAM ( Dioscorea bulbifera L. TO PREDICT ITS POSSIBLE TECHNOLOGICAL USES

Directory of Open Access Journals (Sweden)

Ninoska Meaño Correa

2018-04-01

Full Text Available In Venezuela, the starches are mostly obtained from corn, potato, yuca and rice. Nonetheless, there are other sources for starch production and local consumption whose potential could be exploited, seeking alternatives to increase the added value to local agricultural products. Question arose about to evaluate chemical and functional properties of native starch from congo yam in order to predict its possible uses. With this purpose, bulbs of congo yam were collected in the town of Santa Ana of Anzoategui state, Venezuela, and starch was extracted from them for evaluating the yield, purity, chemical composition, amylose content, gel clarity, swelling power and solubility. The starch yield was 7.44%, and its purity was 99.29%. The chemical composition (on dry basis was of 11.29% moisture, 0.29% protein, 0.21% fat, 0.21% ash and 0.0047% phosphorus. The average content of amylose and amylopectin was 30.63 and 69.37%, respectively. As to the functional properties of starchits swelling power had a maximum of 49.05 g gel/g of starch at 95°C, clear gel formation with a transmittance rate of 91 % and a solubility that increases as the temperature rises. These results indicate that the yam congo is a source of starch with advantageous properties, a high amylose content, a clear gel with high swelling power

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 phosphorylation plays an important role in starch biosynthesis

NARCIS (Netherlands)

Xu, Xuan; Dees, Dianka; Dechesne, Annemarie; Huang, Xing Feng; Visser, Richard G.F.; Trindade, Luisa M.

2017-01-01

Starch phosphate esters are crucial in starch metabolism and render valuable functionality to starches for various industrial applications. A potato glucan, water dikinase (GWD1) was introduced in tubers of two different potato genetic backgrounds: an amylose-containing line Kardal and the

Formation of inclusion complexes between high amylose starch and octadecyl ferulate via steam jet cooking

Science.gov (United States)

Amylose can form inclusion complexes with guest molecules and represents an interesting approach to deliver bioactive molecules. However, ferulic acid has been shown not to form single helical inclusion complexes with amylose. To overcome this problem a ferulic acid ester, octadecyl ferulate, posses...

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.

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.

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.

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...

Production of amorphous starch powders by solution spray drying

NARCIS (Netherlands)

Niazi, Muhammad B. K.; Broekhuis, Antonius A.

2012-01-01

The spray drying of starch/maltodextrin formulations was evaluated as a potential technology for the manufacturing of amorphous thermoplastic starches. Mixtures of starches with high to low amylose (Am)amylopectin (Ap) ratios were spray-dried from water-based solutions and granular dispersions. The

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 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).

Physicochemical properties of potato and cassava starches and their mutants in relation to their structural properties

NARCIS (Netherlands)

Gomand, S.V.; Lamberts, L.; Visser, R.G.F.; Delcour, J.A.

2010-01-01

Physicochemical properties [swelling power (SP), pasting behaviour and retrogradation] of five wild type (wt), five amylose free (amf), four high-amylose (ha) potato starches (ps) and one wt and amf cassava starch (cs) were investigated. While swelling of wtps occurred in two phases, amfps showed a

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.

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.

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.

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)

Plant-crafted starches for bioplastics production

DEFF Research Database (Denmark)

Sagnelli, Domenico; Hebelstrup, Kim H.; Leroy, Eric

2016-01-01

Transgenically-produced amylose-only (AO) starch was used to manufacture bioplastic prototypes. Extruded starch samples were tested for crystal residues, elasticity, glass transition temperature, mechanical properties, molecular mass and microstructure. The AO starch granule crystallinity was both...... in the storage modulus (E') for AO samples compared to the control. The data support the use of pure starch-based bioplastics devoid of non-polysaccharide fillers....... of the B- and Vh-type, while the isogenic control starch was mainly A-type. The first of three endothermic transitions was attributed to gelatinization at about 60°C. The second and third peaks were identified as melting of the starch and amylose-lipid complexes, respectively. After extrusion, the AO...

Factors influencing gene silencing of granule-bound starch synthase in potato

NARCIS (Netherlands)

Heilersig, H.J.B.

2005-01-01

In the past, antisense RNA technology was used to modify the composition of potato tuber starch. Potato starch comprises amylose and amylopectin, polymers of glucose. Amylose production in potato is completely dependent on the presence of granule-bound starch synthase I (GBSSI). Inhibition of GBSSI

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.

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

Physicochemical properties of starches and proteins in alkali-treated mungbean and cassava starch granules.

Science.gov (United States)

Israkarn, Kamolwan; Na Nakornpanom, Nantarat; Hongsprabhas, Parichat

2014-05-25

This study explored the influences of envelope integrity of cooked starch granules on physicochemical and thermophysical properties of mungbean and cassava starches. Alkali treatment was used to selectively leach amylose from the amorphous region of both starches and partially fragmented starch molecules into lower-molecular-weight polymers. It was found that despite the loss of 40% of the original content of amylose, both mungbean and cassava starches retained similar crystallinities, gelatinization temperature ranges, and pasting profiles compared to the native starches. However, the loss of granule-bound starch synthases during alkali treatment and subsequent alkali cooking in excess water played significant roles in determining granular disintegration. The alterations in envelope integrity due to the negative charge repulsion among polymers within the envelope of swollen granules, and the fragmentation of starch molecules, were responsible for the alterations in thermophysical properties of mungbean and cassava starches cooked under alkaline conditions. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

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.

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.

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.)

Effect of starch isolation method on properties of sweet potato starch

Directory of Open Access Journals (Sweden)

A. SURENDRA BABU

2014-08-01

Full Text Available Isolation method of starch with different agents influences starch properties, which provide attention for studying the most appropriate method for isolation of starch. In the present study sweet potato starch was isolated by Sodium metabisulphate (M1, Sodium chloride (M2, and Distilled water (M3 methods and these were assessed for functional, chemical, pasting and structural properties. M3 yielded the greatest recovery of starch (10.20%. Isolation methods significantly changed swelling power and pasting properties but starches exhibited similar chemical properties. Sweet potato starches possessed C-type diffraction pattern. Small size granules of 2.90 μm were noticed in SEM of M3 starch. A high degree positive correlation was found between ash, amylose, and total starch content. The study concluded that isolation methods brought changes in yield, pasting and structural properties of sweet potato starch.

Cultivar difference in physicochemical properties of starches and flours from temperate rice of Indian Himalayas.

Science.gov (United States)

Mir, Shabir Ahmad; Bosco, Sowriappan John Don

2014-08-15

Starch and flour of seven temperate rice cultivars grown in Himalayan region were evaluated for composition, granule structure, crystallinity, Raman spectrometry, turbidity, swelling power, solubility, pasting properties and textural properties. The rice cultivars showed medium to high amylose content for starch (24.69-32.76%) and flour (17.78-24.86%). SKAU-382 showed the highest amount of amylose (32.76%). Rice starch showed polyhedral granule shapes and differences in their mean granule size (2.3-6.5 μm) were noted among the samples. The starch and flour samples showed type A-pattern with strong reflection at 15, 18, and 23. Pasting profile and textural analysis of rice starch and flour showed that all the cultivars differences, probably due to variation in amylose content. The present study can be used for identifying differences between rice genotypes for starch and flour quality and could provide guidance to possible industries for their end use. Copyright © 2014 Elsevier Ltd. All rights reserved.

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.

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.

Amylose-dicarboxylic acid inclusion complexes: Characterization and comparison to monocarboxylic acid complexes

Science.gov (United States)

One of the main components in starch, amylose is an essentially linear polymer composed of glucose connected through alpha-1,4-bonds. Amylose is well known to form helical inclusion complexes with various types of ligands such as iodine, medium and long chain fatty acids, alcohols, lactones, and fl...

Mice fed a high-fat diet supplemented with resistant starch display marked shifts in the liver metabolome concurrent with altered gut bacteria

Science.gov (United States)

High-amylose maize resistant starch type 2 (HAMRS2) is a fermentable dietary fiber known to alter the gut milieu, including the gut microbiota, which may explain reported effects of resistant starch to ameliorate obesity-associated metabolic dysfunction. Our working hypothesis is that HAMRS2-induced...

Effect of genotype and environment on the concentrations of starch and protein in, and the physicochemical properties of starch from, field pea and fababean.

Science.gov (United States)

Hood-Niefer, Shannon D; Warkentin, Thomas D; Chibbar, Ravindra N; Vandenberg, Albert; Tyler, Robert T

2012-01-15

The effects of genotype and environment and their interaction on the concentrations of starch and protein in, and the amylose content and thermal and pasting properties of starch from, pea and fababean are not well known. Differences due to genotype were observed in the concentrations of starch and protein in pea and fababean, in the onset temperature (To) and peak temperature (Tp) of gelatinization of fababean starch, and in the pasting, trough, cooling and final viscosities of pea starch and fababean starch. Significant two-way interactions (location × genotype) were observed for the concentration of starch in fababean and the amylose content, To, endothermic enthalpy of gelatinization (ΔH) and trough viscosity of fababean starch. Significant three-way interactions (location × year × genotype) were observed for the concentration of starch in pea and the pasting, trough, cooling and final viscosities of pea starch. Differences observed in the concentrations of starch and protein in pea and fababean were sufficient to be of practical significance to end-users, but the relatively small differences in amylose content and physicochemical properties of starch from pea and fababean were not. Copyright © 2011 Society of Chemical Industry.

55 ISSN 1119-7455 EFFECT OF SELECTION ON AMYLOSE AND ...

African Journals Online (AJOL)

sys01

2011-09-03

Sep 3, 2011 ... dextrin, syrup and alcohol(Anon, 2011; Smith,. 1974). There is potential industrial outlet for a new type of maize with starch of high amylose .... days from the date of planting were regarded as early maturing, while those that silked at 60 days and above were regarded as late maturing. (Fajemisin, 1985).

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.

Starch accumulation in hulless barley during grain filling.

Science.gov (United States)

Zheng, Xu-Guang; Qi, Jun-Cang; Hui, Hong-Shan; Lin, Li-Hao; Wang, Feng

2017-12-01

Starch consists of two types of molecules: amylose and amylopectin. The objective of this study was increase understanding about mechanisms related to starch accumulation in hulless barley (Hordeum vulgare L.) grain by measuring temporal changes in (i) grain amylose and amylopectin content, (ii) starch synthase activity, and (iii) the relative expressions of key starch-related genes. The amylopectin/amylose ratio gradually declined in both Beiqing 6 and Kunlun 12. In both cultivars, the activities of adenosine diphosphate glucose pyrophosphorylase, soluble starch synthase (SSS), granule bound starch synthase (GBSS), and starch branching enzyme (SBE) increased steadily during grain filling, reaching their maximums 20-25 days after anthesis. The activities of SSS and SBE were greater in Ganken 5 than in either Beiqing 6 or Kunlun 12. The expression of GBSS I was greater in Beiqing 6 and Kunlun 12 than in Ganken 5. In contrast, the expression of SSS I, SSS II and SBE I was greater in Ganken 5 than in Beiqing 6 and Kunlun 12. The peak in GBSS I expression was later than that of SSS I, SSS II, SBE IIa and SBE IIb. The GBSS I transcript in Kunlun 12 was expressed on average 90 times more than the GBSS II transcript. The results suggest that SBE and SSS may control starch synthesis at the transcriptional level, whereas GBSS I may control starch synthesis at the post transcriptional level. GBSS I is mainly responsible for amylose synthesis whereas SSS I and SBE II are mainly responsible for amylopectin synthesis in amyloplasts.

Development of Corn Starch-Neusilin UFL2 Conjugate as Tablet Superdisintegrant: Formulation and Evaluation of Fast Disintegrating Tablets

Directory of Open Access Journals (Sweden)

Prateek Juneja

2014-01-01

Full Text Available In the present study, corn Starch-Neusilin UFL2 conjugates were prepared by physical, chemical, and microwave methods with the aim of using the conjugates as tablet superdisintegrant. Various powder tests, namely, angle of repose, bulk density, tapped density, Hausner’s ratio, Carr’s index, swelling index, and powder porosity were conducted on the samples. The conjugates were characterized by ATR-FTIR, XRD, DSC, and SEM techniques. Heckel and Kawakita models were applied to carry out compression studies for the prepared conjugates. Fast disintegrating tablets of domperidone were prepared using corn starch and corn Starch-Neusilin UFL2 conjugates as tablet superdisintegrants in different concentrations. Conjugates were found to possess good powder flow and tabletting properties. Heckel analysis indicated that the conjugates prepared by microwave method showed the slowest onset of plastic deformation while Kawakita analysis indicated that the conjugates prepared by microwave method exhibited the highest amount of total plastic deformation. The study revealed that the corn Starch-Neusilin UFL2 conjugates possess improved powder flow properties and could be a promising superdisintegrant for preparing fast disintegrating tablet. Also, the results sugessted that the microwave method was found to be most effective for the preparation of corn Starch-Neusilin UFL2 conjugates.

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.

Quinoa Starch Characteristics and Their Correlations with the Texture Profile Analysis (TPA) of Cooked Quinoa.

Science.gov (United States)

Wu, Geyang; Morris, Craig F; Murphy, Kevin M

2017-10-01

Starch characteristics significantly influence the functionality and end-use quality of cereals and pseudo-cereals. This study examined the composition and properties of starch from 11 pure varieties and 2 commercial samples of quinoa in relationship to the texture of cooked quinoa. Nearly all starch properties and characteristics differed among these samples. Results showed that total starch content of seeds ranged from 53.2 to 75.1 g/100 g apparent amylose content ranged from 2.7% to 16.9%; total amylose ranged from 4.7% to 17.3%; and the degree of amylose-lipid complex ranged from 3.4% to 43.3%. Amylose leaching ranged from 31 mg/100 g starch in "Japanese Strain" to 862 mg/100 g starch in "49ALC." "Japanese Strain" starch also exhibited the highest water solubility (4.5%) and the lowest swelling power (17). α-Amylase activity in "1ESP," "Col.#6197," "Japanese Strain," "QQ63," "Yellow Commercial," and "Red Commercial" (0.03 to 0.09 CU) were significantly lower than the levels of the other quinoa samples (0.20 to 1.16 CU). Additionally, gel texture, thermal properties, and pasting properties of quinoa starches were investigated. Lastly, correlation analysis showed that the quinoa samples with higher amylose content tended to yield harder, stickier, more cohesive, more gummy, and more chewy texture after cooking. A higher degree of amylose-lipid complex and amylose leaching were associated with softer and less chewy cooked quinoa TPA texture. Higher starch enthalpy correlated with firmer, more adhesive, more cohesive, and chewier texture. In sum, starch plays a significant role in the texture of cooked quinoa. The research determined starch characteristics among a diverse set of pure quinoa varieties and commercial samples, and identified the relationships between starch properties and cooked quinoa texture. The results can help breeders and food manufacturers to understand better the relationships among quinoa starch characteristics, cooked quinoa texture, and

Structural properties and gelatinisation characteristics of potato and cassava starches and mutants thereof

NARCIS (Netherlands)

Gomand, S.V.; Lamberts, L.; Derde, L.J.; Groesaert, H.; Vandeputte, G.E.; Goderis, B.; Visser, R.G.F.; Delcour, J.A.

2010-01-01

The molecular size of amylopectin (AP) and amylose (AM), AP chain length distribution, crystallinity and granular structure (morphology and granule size distribution) of five wild type potato starches (wtps), five AM free potato starches (amfps), four high-AM potato starches (haps), one wild type

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.

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.

Modulating rheo-kinetics of native starch films towards improved wet-strength

DEFF Research Database (Denmark)

Gillgren, Thomas; Blennow, Andreas; Pettersson, Anders J.

2011-01-01

properties of the films – an increase in the amylose content resulted in both a higher stress and strain at break. Interestingly, there was no correlation between the speed of hydration and mechanical water resistance of the films. Generally, the films were clear and transparent, even after wetting...... highly different starch types derived from potato and cereal sources of normal and mutant and transgenic backgrounds. A new improved technique was developed to permit the dynamic mechanical analysis of films in the presence of water. It was found that the amylose content was decisive for the mechanical....... Transgenic potato starch with a low content of phosphate displayed an extraordinary combination of high robustness, transparency, mechanical strength and extensibility even in a wet condition. The combination of optimal phosphate and amylose concentrations in this sample probably favoured hydration...

Determination of surface energies of hot-melt extruded sugar-starch pellets.

Science.gov (United States)

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.

The effect of temperature and time on the formation of amylose- lysophosphatidylcholine inclusion complexes

NARCIS (Netherlands)

Ahmadi-Abhari, S.; Woortman, A.J.J.; Oudhuis, A.A.C.M.; Hamer, R.J.; Loos, K.

2014-01-01

The formation of amylose inclusion complexes could help to decrease the susceptibility of starch granules against amylase digestion. We studied the formation of amyloselysophosphatidylcholine (LPC) inclusion complexes at temperatures at and below the gelatinization temperature of starch, using DSC,

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

Starch Digestibility and Functional Properties of Rice Starch Subjected to Gamma Radiation

Directory of Open Access Journals (Sweden)

Luís Fernando Polesi

2018-01-01

Full Text Available This study investigated the effect of gamma radiation on the digestibility and functional properties of rice starch. Rice cultivars IRGA417 and IAC202 were used for isolation of starch by the alkaline method. Starch samples were irradiated with 1, 2 and 5 kGy doses of 60Co at a rate of 0.4 kGy/h. A control sample, which was not irradiated, was used for comparison. Irradiated and control starches were characterized by in vitro starch digestibility, total dietary fiber, color, water absorption index, water solubility index, syneresis, swelling factor, amylose leaching, pasting properties and gel firmness. Irradiations changed starch digestibility differently in either cultivar. Increasing radiation doses promoted increase in the color parameter b* (yellow, elevation in the capacity to absorb water, and solubility in water as well as the amylose leached from granules for both cultivars. Pasting properties showed a decrease that was proportional to the dose applied, caused by the depolymerization of starch molecules. Gel firmness of the starch from IAC202 was inversely proportional to the radiation dose applied, whereas for IRGA417, there was a reduction at 5 kGy dose. Rice starches can be modified by irradiation to exhibit different functional characteristics and they can be used by the food industries in products such as soups, desserts, flans, puddings and others.

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.

Plant-crafted starches for bioplastics production.

Science.gov (United States)

Sagnelli, Domenico; Hebelstrup, Kim H; Leroy, Eric; Rolland-Sabaté, Agnès; Guilois, Sophie; Kirkensgaard, Jacob J K; Mortensen, Kell; Lourdin, Denis; Blennow, Andreas

2016-11-05

Transgenically-produced amylose-only (AO) starch was used to manufacture bioplastic prototypes. Extruded starch samples were tested for crystal residues, elasticity, glass transition temperature, mechanical properties, molecular mass and microstructure. The AO starch granule crystallinity was both of the B- and Vh-type, while the isogenic control starch was mainly A-type. The first of three endothermic transitions was attributed to gelatinization at about 60°C. The second and third peaks were identified as melting of the starch and amylose-lipid complexes, respectively. After extrusion, the AO samples displayed Vh- and B-type crystalline structures, the B-type polymorph being the dominant one. The AO prototypes demonstrated a 6-fold higher mechanical stress at break and 2.5-fold higher strain at break compared to control starch. Dynamic mechanical analysis showed a significant increase in the storage modulus (E') for AO samples compared to the control. The data support the use of pure starch-based bioplastics devoid of non-polysaccharide fillers. Copyright © 2016 Elsevier Ltd. All rights reserved.

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.

Structure of potato starch

DEFF Research Database (Denmark)

Bertoft, Eric; Blennow, Andreas

2016-01-01

Potato starch granules consist primarily of two tightly packed polysaccharides, amylose and amylopectin. Amylose, which amount for 20-30%, is the principal linear component, but a fraction is in fact slightly branched. Amylopectin is typically the major component and is extensively branched...... chains extending from the clusters. A range of enzymes is involved in the biosynthesis of the cluster structures and linear segments. These are required for sugar activation, chain elongation, branching, and trimming of the final branching pattern. As an interesting feature, potato amylopectin...... is substituted with low amounts of phosphate groups monoesterified to the C-3 and the C-6 carbons of the glucose units. They seem to align well in the granular structure and have tremendous effects on starch degradation in the potato and functionality of the refined starch. A specific dikinase catalyzes...

Determination of the structural changes by Raman and {sup 13}C CP/MAS NMR spectroscopy on native corn starch with plasticizers

Energy Technology Data Exchange (ETDEWEB)

Cozar, O. [Academy of Romanian Scientists, Splaiul Independentei 54, 050094, Bucharest, Romania and National Institute of Research-Development for Machines and Installations Designed to Agriculture and Food Industry - INMA Bucureşti - Cluj-Napoca Branch (Romania); Filip, C.; Tripon, C. [National Institute for Research and Development of Isotopic and Molecular Technologies, 65-103 Donath, 400293 Cluj-Napoca (Romania); Cioica, N.; Coţa, C.; Nagy, E. M. [National Institute of Research-Development for Machines and Installations Designed to Agriculture and Food Industry - INMA Bucureşti - Cluj-Napoca Branch, RO-400458 Cluj-Napoca (Romania)

2013-11-13

The plasticizing - antiplasticizing effect of water and glycerol contents on native corn starch samples is investigated by FT-Raman and {sup 13}C CP/MAS NMR spectroscopy. The presence of both amorphous and crystalline structural phases was evidenced in pure native corn starch and also in the samples containing plasticizers. Among the crystalline starch structures, the A- and V- types were suggested by CP/MAS NMR spectra.

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)

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...

Sixth taste – starch taste?

Directory of Open Access Journals (Sweden)

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.

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)

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 charge-carrying amino acids on the gelatinization and retrogradation properties of potato starch.

Science.gov (United States)

Chen, Wenting; Zhou, Hongxian; Yang, Hong; Cui, Min

2015-01-15

The objective of this study was to evaluate the effects of charge-carrying amino acids (lysine (Lys), arginine (Arg), aspartic acid (Asp) and glutamic acid (Glu)) on the gelatinization and retrogradation properties of potato starch. Acidic amino acids (Asp and Glu) showed a decreasing trend in swelling power and granule size of potato starch, but increased amylose leaching and gelatinization temperature. Alkaline amino acid (Arg) showed an increasing trend in swelling power and granule size of potato starch, but decreasing amylose leaching and gelatinization temperature. Lys had no effect on the swelling power of potato starch, except at a high content (0.2 mol/kg). Like other two acidic amino acids, Lys also increased gelatinization temperature. Moreover, the addition of alkaline amino acids (Arg) decreased syneresis value of potato starch but acidic amino acids (Asp and Glu) increased it. Compared to Arg, the syneresis of potato starch with Lys was similar to that of its native starch. Copyright © 2014 Elsevier Ltd. All rights reserved.

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.

Physicochemical properties and in vitro digestibility of sorghum starch altered by high hydrostatic pressure.

Science.gov (United States)

Liu, Hang; Fan, Huanhuan; Cao, Rong; Blanchard, Christopher; Wang, Min

2016-11-01

A nonthermal processing technology, high hydrostatic pressure (HHP) treatment, was investigated to assess its influence on the physicochemical properties and in vitro digestibility of sorghum starch (SS). There was no change in the 'A'-type crystalline pattern of SS after the pressure treatments at 120-480MPa. However, treatment at 600MPa produced a pattern similar to 'B'-type crystalline. HHP treatment also resulted in SS granules with rough surfaces. Measured amylose content, water absorption capacity, alkaline water retention, pasting temperature and thermostability increased with increasing pressure levels, while the oil absorption capacity, swelling power, relative crystallinity and viscosity decreased. Compared with native starch, HHP-modified SS samples had lower in vitro hydrolysis, reduced amount of rapidly digestible starch, as well as increased levels of slowly digestible starch and resistant starch. These results indicate that HHP treatment is an effective modification method for altering in vitro digestibility and physicochemical properties of SS. Copyright © 2016 Elsevier B.V. All rights reserved.

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.

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

KRISTALINITAS DAN KEKERASAN BERAS ANALOG YANG DIHASILKAN DARI PROSES EKSTRUSI PANAS TEPUNG JAGUNG

Directory of Open Access Journals (Sweden)

Faleh Setia Budi

2017-06-01

Full Text Available Rice analogues are food products made from broken rice and/or any other carbohydrate sources to have similar texture and shape to those of rice. Corn flour can be used as a material to make the rice analogues because it has various amylose contents ranging from low, medium, and high so that it is possible to make the dough with different levels of amylose contents. High temperature extrusion process may change crystallinity of starch (crystal type of A to V and degree of crystallization. Changes in starch crystallinity may influence the physical properties of the rice analogue produced. This research aimed to assess the effect of flour amylose content and temperature of extrusion on the crystallinity and its impact on physical properties of rice analogue. High amylose corn starch and corn flour were mixed at certain ratios to obtain amylose contents of 16.99, 19.35, 21.72, and 24.09%. The dough was made by adding water to the mixed flour to have a moisture content of 40%. The dough was then extruded at temperatures of 70, 80, and 90°C using a twin screw extruder (BEX-DS-2256 Berto. The observed physical properties were type of crystal, degree of crystallinity, and hardness of the rice analogue. The results showed that the increase in extrusion temperatures from 70°C to 90°C increased the degree of crystallinity of the rice analogues from 7.98-11.49% to 12.15-13.61% and hardness from 4.06-4.91 kg to 4.74-8.20 kg. The increase in amylose contents (from 16.99% to 24.09% enhanced the hardness of the rice analogue from 4.06-4.74 kg to 4.91-8.20 kg but did not show any significant effects on the degree of crystallinity. The degree of crystallinity is positively correlated with the hardness of rice analogue (correlation coefficient r=0.8.

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.

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.

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.

Dynamic development of starch granules and the regulation of starch biosynthesis in Brachypodium distachyon: comparison with common wheat and Aegilops peregrina.

Science.gov (United States)

Chen, Guanxing; Zhu, Jiantang; Zhou, Jianwen; Subburaj, Saminathan; Zhang, Ming; Han, Caixia; Hao, Pengchao; Li, Xiaohui; Yan, Yueming

2014-08-06

Thorough understanding of seed starch biosynthesis and accumulation mechanisms is of great importance for agriculture and crop improvement strategies. We conducted the first comprehensive study of the dynamic development of starch granules and the regulation of starch biosynthesis in Brachypodium distachyon and compared the findings with those reported for common wheat (Chinese Spring, CS) and Aegilops peregrina. Only B-granules were identified in Brachypodium Bd21, and the shape variation and development of starch granules were similar in the B-granules of CS and Bd21. Phylogenetic analysis showed that most of the Bd21 starch synthesis-related genes were more similar to those in wheat than in rice. Early expression of key genes in Bd21 starch biosynthesis mediate starch synthesis in the pericarp; intermediate-stage expression increases the number and size of starch granules. In contrast, these enzymes in CS and Ae. peregrina were mostly expressed at intermediate stages, driving production of new B-granules and increasing the granule size, respectively. Immunogold labeling showed that granule-bound starch synthase (GBSSI; related to amylose synthesis) was mainly present in starch granules: at lower levels in the B-granules of Bd21 than in CS. Furthermore, GBSSI was phosphorylated at threonine 183 and tyrosine 185 in the starch synthase catalytic domain in CS and Ae. peregrina, but neither site was phosphorylated in Bd21, suggesting GBSSI phosphorylation could improve amylose biosynthesis. Bd21 contains only B-granules, and the expression of key genes in the three studied genera is consistent with the dynamic development of starch granules. GBSSI is present in greater amounts in the B-granules of CS than in Bd21; two phosphorylation sites (Thr183 and Tyr185) were found in Triticum and Aegilops; these sites were not phosphorylated in Bd21. GBSSI phosphorylation may reflect its importance in amylose synthesis.

Comparison of Effects of Oligosaccharides on Physicochemical ...

African Journals Online (AJOL)

Pharmacotherapy Group, Faculty of Pharmacy, University of Benin, Benin City, 300001 Nigeria. ... purchased from local market. .... Sandhu KS, Singh N. Some properties of corn starches ... wheat flour and starch in relation to amylose content.

Atomic force microscopy of pea starch: origins of image contrast.

Science.gov (United States)

Ridout, Michael J; Parker, Mary L; Hedley, Cliff L; Bogracheva, Tatiana Y; Morris, Victor J

2004-01-01

Atomic force microscopy (AFM) has been used to image the internal structure of pea starch granules. Starch granules were encased in a nonpenetrating matrix of rapid-set Araldite. Images were obtained of the internal structure of starch exposed by cutting the face of the block and of starch in sections collected on water. These images have been obtained without staining, or either chemical or enzymatic treatment of the granule. It has been demonstrated that contrast in the AFM images is due to localized absorption of water within specific regions of the exposed fragments of the starch granules. These regions swell, becoming "softer" and higher than surrounding regions. The images obtained confirm the "blocklet model" of starch granule architecture. By using topographic, error signal and force modulation imaging modes on samples of the wild-type pea starch and the high amylose r near-isogenic mutant, it has been possible to demonstrate differing structures within granules of different origin. These architectural changes provide a basis for explaining the changed appearance and functionality of the r mutant. The growth-ring structure of the granule is suggested to arise from localized "defects" in blocklet distribution within the granule. It is proposed that these defects are partially crystalline regions devoid of amylose.

Altered Tuber Yield in Genetically Modified High-Amylose and Oil Potato Lines Is Associated With Changed Whole-Plant Nitrogen Economy

Directory of Open Access Journals (Sweden)

Fereshteh Pourazari

2018-03-01

increased plant N accumulation compared to the parental variety, the cultivation of the high-amylose line is expected to require higher N fertilization rates. However, starch productivity per unit land area or soil N still is expected to be higher in the high-amylose line.

Altered Tuber Yield in Genetically Modified High-Amylose and Oil Potato Lines Is Associated With Changed Whole-Plant Nitrogen Economy.

Science.gov (United States)

Pourazari, Fereshteh; Andersson, Mariette; Weih, Martin

2018-01-01

plant N accumulation compared to the parental variety, the cultivation of the high-amylose line is expected to require higher N fertilization rates. However, starch productivity per unit land area or soil N still is expected to be higher in the high-amylose line.

Improvement of rice starch by gamma irradiation

International Nuclear Information System (INIS)

Duan Zhiying; Wu Dianxing; Shen Shengquan; Han Juanying; Xia Yingwu

2003-01-01

Three types of rice cultivars, Indica, Japonica and hybrid rice, with similar intermediate apparent amylose content (AAC) as well as early Indica rice cultivars with different amounts of AAC were selected for studying the effects of gamma irradiation on starch viscosity, physico-chemical properties and starch granule structure. Four major parameters of RVA profile, peak viscosity (PKV), hot paste viscosity (HPV), cool paste viscosity (CPV), setback viscosity (SBV) and consistence viscosity (CSV) were considerably decreased with increasing dose levels. Gamma irradiation reduced the amylose contents in the cultivars with low AAC, intermediate AAC, and glutinous rice, but had no effects on the high AAC cultivar. No visible changes in alkali spreading value (ASV) were detected after irradiation, but the peak time (PKT) were reduced with the dose level. Gel consistency (GC) were significantly increased in the tested cultivars, especially in the high AAC Indica rice, suggesting that it is promising to use gamma irradiation to improve eating and cooking quality of rice

Insights into the swelling process and drug release mechanisms from cross-linked pectin/high amylose starch matrices

Directory of Open Access Journals (Sweden)

Fernanda M. Carbinatto

2014-02-01

Full Text Available Cross-linked pectin/high amylose mixtures were evaluated as a new excipient for matrix tablets formulations, since the mixing of polymers and cross-linking reaction represent rational tools to reach materials with modulated and specific properties that meet specific therapeutic needs. Objective: In this work the influence of polymer ratio and cross-linking process on the swelling and the mechanism driving the drug release from swellable matrix tablets prepared with this excipient was investigated. Methods: Cross-linked samples were characterized by their micromeritic properties (size and shape, density, angle of repose and flow rate and liquid uptake ability. Matrix tablets were evaluated according their physical properties and the drug release rates and mechanisms were also investigated. Results: Cross-linked samples demonstrated size homogeneity and irregular shape, with liquid uptake ability insensible to pH. Cross-linking process of samples allowed the control of drug release rates and the drug release mechanism was influenced by both polymer ratio and cross-linking process. The drug release of samples with minor proportion of pectin was driven by an anomalous transport and the increase of the pectin proportion contributed to the erosion of the matrix. Conclusion: The cross-linked mixtures of high amylose and pectin showed a suitable excipient for slowing the drug release rates.

Characteristics of heat transfer fouling of thin stillage using model thin stillage and evaporator concentrates

Science.gov (United States)

Challa, Ravi Kumar

, fiber and minerals, simulated thin stillage was prepared with carbohydrate mixtures and tested for fouling rates. Induction period, maximum fouling resistance and mean fouling rates were determined. Two experiments were performed with two varieties of starch, waxy and high amylose and short chain carbohydrates, corn syrup solids and glucose. Interaction effects of glucose with starch varieties were studied. In the first experiment, short chain carbohydrates individual and interaction effects with starch were studied. For mixtures prepared from glucose and corn syrup solids, no fouling was observed. Mixtures prepared from starch, a long glucose polymer, showed marked fouling. Corn syrup solids and glucose addition to pure starch decreased the mean fouling rates and maximum fouling resistances. Between corn syrup solids and glucose, starch fouling rates were reduced with addition of glucose. Induction periods of pure mixtures of either glucose or corn syrup solids were longer than the test period (5 h). Pure starch mixture had no induction period. Maximum fouling resistance was higher for mixtures with higher concentration of longer polymers. Waxy starch had a longer induction period than high amylose starch. Maximum fouling resistance was higher for waxy than high amylose starch. Addition of glucose to waxy or high amylose starch increased induction period of mixtures longer than 5 h test period. It appears that the bulk fluid temperature plays an important role on carbohydrate mixture fouling rates. Higher bulk fluid temperatures increased the initial fouling rates of the carbohydrate mixtures. Carbohydrate type, depending on the polymer length, influenced the deposit formation. Longer chain carbohydrate, starch, had higher fouling rates compared to shorter carbohydrates such as glucose and corn syrup solids. For insoluble carbohydrate mixtures, fouling was severe. As carbohydrate solubility increased with bulk fluid temperature, surface reaction increased at probe

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

Green composites of thermoplastic corn starch and recycled paper cellulose fibers

Directory of Open Access Journals (Sweden)

Amnuay Wattanakornsiri

2011-08-01

Full Text Available Ecological concerns have resulted in a renewed interest in environmental-friendly composites issues for sustainabledevelopment as a biodegradable renewable resource. In this work we used cellulose fibers from recycled newspaper as reinforcementfor thermoplastic starch in order to improve its mechanical, thermal and water resistance properties. The compositeswere prepared from corn starch plasticized by glycerol (30% wt/wt of glycerol to starch as matrix that was reinforcedwith micro-cellulose fibers, obtained from used newspaper, with fiber content ranging from 0 to 8% (wt/wt of fibers to matrix.Physical properties of composites were determined by mechanical tensile tests, differential scanning calorimetry, thermogravimetricanalysis, water absorption measurement and scanning electron microscopy. The results showed that higherfibers content raised the tensile strength and elastic modulus up to 175% and 292%, respectively, when compared to thenon-reinforced thermoplastic starch. The addition of the fibers improved the thermal resistance and decreased the waterabsorption up to 63%. Besides, scanning electron microscopy illustrated a good adhesion between matrix and fibers. Theseresults indicated that thermoplastic starch reinforced with recycled newspaper cellulose fibers could be fruitfully used ascommodity plastics being strong, cheap, abundant and recyclable.

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.

Effect of parboiling on the formation of resistant starch, digestibility and functional properties of rice flour from different varieties grown in Sri Lanka.

Science.gov (United States)

Gunaratne, Anil; Kao, Wu; Ratnayaka, Jennet; Collado, Lilia; Corke, Harold

2013-08-30

Hydrothermal treatment used in parboiling could induce formation of novel starch properties having potential food applications. In the current work, functional, digestible and retrogradation properties of flour from non-parboiled and steamed parboiled six rice varieties with high amylose content of around 30% but differing in length and width ratio were investigated and compared. The parboiling process reduced swelling volume and amylose leaching in all tested varieties. Among the varieties studied, the resistant starch content ranged from 1.6% in AT 306 to 0.46% in BG 357. Parboiling reduced the resistant starch content in AT 306 by about 50%, but it did not significantly affect the resistant starch content of the other varieties. The amylose-lipid complex remained unchanged after parboiling. Amylopectin retrogradation was not observed in parboiled rice. Amylose retrogradation was not seen except for AT 306. Pasting behaviour of parboiled rice flours showed high pasting stability and low setback. Flours were more susceptible to enzymatic hydrolysis after parboiling. Partial gelatinisation during parboiling was sufficient to produce grains with excellent milling quality showing a head rice recovery that ranged from 98% to 100% among the varieties studied. Degree of gelatinisation is the most important factor that determines the high head rice recovery. High pasting stability and low setback of flour of parboiled rice indicate some potential food applications. © 2013 Society of Chemical Industry.

13CO2 breath test to measure the hydrolysis of various starch formulations in healthy subjects.

OpenAIRE

Hiele, M; Ghoos, Y; Rutgeerts, P; Vantrappen, G; de Buyser, K

1990-01-01

13CO2 starch breath test was used to study the effect of physicochemical characteristics of starch digestion. As starch is hydrolysed to glucose, which is subsequently oxidised to CO2, differences in 13CO2 excretion after ingestion of different starch products must be caused by differences in hydrolysis rate. To study the effect of the degree of chain branching, waxy starch, containing 98% amylopectin, was compared with high amylose starch, containing 30% amylopectin, and normal crystalline s...

Influence of starch origin on rheological properties of concentrated aqueous solutions

Directory of Open Access Journals (Sweden)

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.

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 ...

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.

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

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, ...

Development of waxy cassava with different Biological and physico-chemical characteristics of starches for industrial applications.

Science.gov (United States)

Zhao, Shan-Shan; Dufour, Dominique; Sánchez, Teresa; Ceballos, Hernan; Zhang, Peng

2011-08-01

The quality of cassava starch, an important trait in cassava breeding programs, determines its applications in various industries. For example, development of waxy (having a low level of amylose) cassava is in demand. Amylose is synthesized by granule-bound starch synthase I (GBSSI) in plants, and therefore, down-regulation of GBSSI expression in cassava might lead to reduced amylose content. We produced 63 transgenic cassava plant lines that express hair-pin dsRNAs homologous to the cassava GBSSI conserved region under the control of the vascular-specific promoter p54/1.0 from cassava (p54/1.0::GBSSI-RNAi) or cauliflower mosaic virus (CaMV) 35S (35S::GBSSI-RNAi). After the screening storage roots and starch granules from field-grown plants with iodine staining, the waxy phenotype was discovered: p54/1.0::GBSSI-RNAi line A8 and 35S::GBSSI-RNAi lines B9, B10, and B23. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that there was no detectable GBSSI protein in the starch granules of plants with the waxy phenotype. Further, the amylose content of transgenic starches was significantly reduced (industrial utilization. Copyright © 2011 Wiley Periodicals, Inc.

Plant α-glucan phosphatases SEX4 and LSF2 display different affinity for amylopectin and amylose

DEFF Research Database (Denmark)

Wilkens, Casper; Auger, Kyle D.; Anderson, Nolan T.

2016-01-01

The plant glucan phosphatases Starch EXcess 4 (SEX4) and Like Sex Four2 (LSF2) apply different starch binding mechanisms. SEX4 contains a carbohydrate binding module, and LSF2 has two surface binding sites (SBSs). We determined KDapp for amylopectin and amylose, and KD for β-cyclodextrin and vali...

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.

Digestion and Interaction of Starches with α-Amylases: I. Mutational analysis of Carbohydrate Binding Sites in barley. II. In Vitro Starch Digestion of Legumes

DEFF Research Database (Denmark)

Nielsen, Morten Munch

2006-01-01

the hydrolysis of internal 1,4-α-D-glucosidic bonds in starch and related polysaccharides. The present thesis concerns studies of two α-amylases: 1) secondary substrate binding sites in barley α-amylase 1 (AMY1), and 2) the involvement of anti-nutrients in in vitro digestion of starch in legumes by porcine...... in morphology between high amylose starch granules and normal starch granules. Legumes (beans, peas, and lentils) are characterised by low blood glucose raising potential, which is proportional to the in vitro starch digestion rates. The high amount of anti-nutritional factors (phytate, proteinaceous inhibitors......, tannins, and lectins) in legumes has been associated with the slow starch digestion. However, it is still debated in literature to which extent the legume starch digestibility is affected by anti-nutritional factors. The in vitro starch digestion (hydrolytic index, HI) of pea (Pisum sativum) and mixtures...

Aroma interactions with starch

DEFF Research Database (Denmark)

Jørgensen, Anders Dysted

Starches are used to enhance aroma perception in low-fat foods. Aroma compounds can bind physically to the starch in grooves on the surface or they can form complexes inside amylose helices. This study has been divided into two parts: one part regarding binding of aromas to starches and their aroma......-release, and another part regarding stimulation of a fungal secretome using different carbohydrates. In the first part, nine aromas and one aroma-mixture were mixed with nine different starches, including genetically modified starches. The objective of this sub-project was to bind aromas to the starches to 15 weight......-percent. Aroma binding was tested on both amorphous starches and on native starch granules. A series of aldehydes and alcohols were also tested for binding to the starches. The aromas with the highest volatility were positively retained by starch, whereas for aromas with a lower volatility the starch had...

Engineering Potato Starch with a Higher Phosphate Content.

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Xuan Xu

Full Text Available Phosphate esters are responsible for valuable and unique functionalities of starch for industrial applications. Also in the cell phosphate esters play a role in starch metabolism, which so far has not been well characterized in storage starch. Laforin, a human enzyme composed of a carbohydrate-binding module and a dual-specificity phosphatase domain, is involved in the dephosphorylation of glycogen. To modify phosphate content and better understand starch (dephosphorylation in storage starch, laforin was engineered and introduced into potato (cultivar Kardal. Interestingly, expression of an (engineered laforin in potato resulted in significantly higher phosphate content of starch, and this result was confirmed in amylose-free potato genetic background (amf. Modified starches exhibited altered granule morphology and size compared to the control. About 20-30% of the transgenic lines of each series showed red-staining granules upon incubation with iodine, and contained higher phosphate content than the blue-stained starch granules. Moreover, low amylose content and altered gelatinization properties were observed in these red-stained starches. Principle component and correlation analysis disclosed a complex correlation between starch composition and starch physico-chemical properties. Ultimately, the expression level of endogenous genes involved in starch metabolism was analysed, revealing a compensatory response to the decrease of phosphate content in potato starch. This study provides a new perspective for engineering starch phosphate content in planta by making use of the compensatory mechanism in the plant itself.

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

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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.

1H-13C NMR-based profiling of biotechnological starch utilization

DEFF Research Database (Denmark)

Sundekilde, Ulrik K.; Meier, Sebastian

2016-01-01

Starch is used in food-and non-food applications as a renewable and degradable source of carbon and energy. Insight into the chemical detail of starch degradation remains challenging as the starch constituents amylose and amylopectin are homopolymers. We show that considerable molecular detail...... of starch fragmentation can be obtained from multivariate analysis of spectral features in optimized 1H-13C NMR spectroscopy of starch fragments to identify relevant features that distinguish processes in starch utilization. As a case study, we compare the profiles of starch fragments in commercial beer...... samples. Spectroscopic profiles of homooligomeric starch fragments can be excellent indicators of process conditions. In addition, differences in the structure and composition of starch fragments have predictive value for down-stream process output such as ethanol production from starch. Thus, high...

Supply of avocado starch (Persea americana mill) as bioplastic material

Science.gov (United States)

Ginting, M. H. S.; Hasibuan, R.; Lubis, M.; Alanjani, F.; Winoto, F. A.; Siregar, R. C.

2018-02-01

The purpose of this study was to determine the effect of time precipitation of avocado slurry seed to yield of starch. Starch analysis included starch content, moisture content, amylose content, amylopectin content, ash content, protein content, fat content, Fourier transform infra red analysis and rapid visco analyzer. Supply of starch from avocado seeds was used by extraction method. Every one hundred grams of avocado slurry was precipitated by gravity with variations for 4 hours, 8 hours, 12 hours, 16 hours, 20 hours and 24 hours. The Starch yield was washed, and dried using oven at 70°C for 30 minutes. Starch yield was the highest as 24.20 gram at 24 hours. The result of starch characterization was 73.62%, water content 16.6%, amylose 0.07%, amylopectin 73.55%, ash content 0.23%, protein content 2.16%, fat content 1.09%. Rapid visco analyzer obtained at 91.33°C of gelatinization temperature. Scanning electron microscopy analyzes obtained 20 μm oval-shaped starch granules. Fourier Transform Infra Red analysis of starch obtained the peak spectrum of O-H group of alcohols, C-H alkanes and C-O ether.

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.

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.

Chemical and rheological properties of a starch-rich fraction from the pulp of the fruit cupuassu (Theobroma grandiflorum)

International Nuclear Information System (INIS)

Vriesmann, Lucia C.; Silveira, Joana L.M.; Petkowicz, Carmen L. de O

2009-01-01

The pulp obtained from the fruit of cupuassu (Theobroma grandiflorum) was extracted with hot aqueous 0.1% citric acid to give fraction 0.1CA-2 in 15% yield. This was the predominant component polysaccharide, 91% of which was composed of starch, by an iodine test and monosaccharide composition, and its 13 C NMR spectrum was consistent with that of a high amylose starch. The content of amylose found in fraction 0.1CA-2 was 71%. This value is higher than those of common starches of cereal grains, tubers, roots, and other fruits. The fraction was submitted to rheological examination, gels being prepared on heating with concentrations of 4 to 7% (w/w). A non-Newtonian behavior was observed, and gel viscosity and strength depended on the concentration. The presence of starch, as well as the presence of previously investigated pectin, conferred the high viscosity and gelling capability of the pulp

Chemical and rheological properties of a starch-rich fraction from the pulp of the fruit cupuassu (Theobroma grandiflorum)

Energy Technology Data Exchange (ETDEWEB)

Vriesmann, Lucia C.; Silveira, Joana L.M. [Universidade Federal do Parana, Departamento de Bioquimica e Biologia Molecular, CP 19046, CEP 81531-990, Curitiba-PR (Brazil); Petkowicz, Carmen L. de O [Universidade Federal do Parana, Departamento de Bioquimica e Biologia Molecular, CP 19046, CEP 81531-990, Curitiba-PR (Brazil)], E-mail: clop@ufpr.br

2009-03-01

The pulp obtained from the fruit of cupuassu (Theobroma grandiflorum) was extracted with hot aqueous 0.1% citric acid to give fraction 0.1CA-2 in 15% yield. This was the predominant component polysaccharide, 91% of which was composed of starch, by an iodine test and monosaccharide composition, and its {sup 13}C NMR spectrum was consistent with that of a high amylose starch. The content of amylose found in fraction 0.1CA-2 was 71%. This value is higher than those of common starches of cereal grains, tubers, roots, and other fruits. The fraction was submitted to rheological examination, gels being prepared on heating with concentrations of 4 to 7% (w/w). A non-Newtonian behavior was observed, and gel viscosity and strength depended on the concentration. The presence of starch, as well as the presence of previously investigated pectin, conferred the high viscosity and gelling capability of the pulp.

Isolation and partial characterization of starch from banana cultivars grown in Colombia.

Science.gov (United States)

Chávez-Salazar, A; Bello-Pérez, L A; Agama-Acevedo, E; Castellanos-Galeano, F J; Álvarez-Barreto, C I; Pacheco-Vargas, G

2017-05-01

Banana starch is resistant to hydrolysis by digestive enzymes due to its structure and dietary fibre content. Starch was isolated from the following three cultivars of Colombian Musaceae: Gros Michel (dessert), Dominico Harton and FHIA 20 (cooking); also, the amylose and amylopectin contents, morphology of the granules, thermal properties, pasting, molecular characteristics and digestibility were determined. The total starch content, amylose content and digestibility (gelatinized starch) were higher in cooking varieties; the purity and gelatinization temperature were similar for the three varieties, but the enthalpy was higher in the dessert variety. The three varieties showed higher viscosities in the pasting profile compared to commercial maize starch in both acid and neutral conditions. Starch granules presented with heterogeneous sizes and shapes (elongated and ovals) that had birefringence. The Dominico Hartón variety showed the lowest rapidly digestible starch (RDS) value in the gelatinized sample that is in agreement with the greater proportion of long chains. Copyright © 2017 Elsevier B.V. All rights reserved.

Defining Starch Binding by Glucan Phosphatases

DEFF Research Database (Denmark)

Auger, Kyle; Raththagala, Madushi; Wilkens, Casper

2015-01-01

Starch is a vital energy molecule in plants that has a wide variety of uses in industry, such as feedstock for biomaterial processing and biofuel production. Plants employ a three enzyme cyclic process utilizing kinases, amylases, and phosphatases to degrade starch in a diurnal manner. Starch...... is comprised of the branched glucan amylopectin and the more linear glucan amylose. Our lab has determined the first structures of these glucan phosphatases and we have defined their enzymatic action. Despite this progress, we lacked a means to quickly and efficiently quantify starch binding to glucan...

Highly phosphorylated functionalized rice starch produced by transgenic rice expressing the potato GWD1 gene

DEFF Research Database (Denmark)

Chen, Yaling; Sun, Xiao; Zhou, Xin Mao

2017-01-01

Starch phosphorylation occurs naturally during starch metabolism in the plant and is catalysed by glucan water dikinases (GWD1) and phosphoglucan water dikinase/glucan water dikinase 3 (PWD/GWD3). We generated six stable individual transgenic lines by over-expressing the potato GWD1 in rice....... Transgenic rice grain starch had 9-fold higher 6-phospho (6-P) monoesters and double amounts of 3-phospho (3-P) monoesters, respectively, compared to control grain. The shape and topography of the transgenic starch granules were moderately altered including surface pores and less well defined edges....... The gelatinization temperatures of both rice flour and extracted starch were significantly lower than those of the control and hence negatively correlated with the starch phosphate content. The 6-P content was positively correlated with amylose content and relatively long amylopectin chains with DP25-36, and the 3-P...

Effects of starch synthase IIa gene dosage on grain, protein and starch in endosperm of wheat.

Science.gov (United States)

Konik-Rose, Christine; Thistleton, Jenny; Chanvrier, Helene; Tan, Ihwa; Halley, Peter; Gidley, Michael; Kosar-Hashemi, Behjat; Wang, Hong; Larroque, Oscar; Ikea, Joseph; McMaugh, Steve; Regina, Ahmed; Rahman, Sadequr; Morell, Matthew; Li, Zhongyi

2007-11-01

Starch synthases (SS) are responsible for elongating the alpha-1,4 glucan chains of starch. A doubled haploid population was generated by crossing a line of wheat, which lacks functional ssIIa genes on each genome (abd), and an Australian wheat cultivar, Sunco, with wild type ssIIa alleles on each genome (ABD). Evidence has been presented previously indicating that the SGP-1 (starch granule protein-1) proteins present in the starch granule in wheat are products of the ssIIa genes. Analysis of 100 progeny lines demonstrated co-segregation of the ssIIa alleles from the three genomes with the SGP-1 proteins, providing further evidence that the SGP-1 proteins are the products of the ssIIa genes. From the progeny lines, 40 doubled haploid lines representing the eight possible genotypes for SSIIa (ABD, aBD, AbD, ABd, abD, aBd, Abd, abd) were characterized for their grain weight, protein content, total starch content and starch properties. For some properties (chain length distribution, pasting properties, swelling power, and gelatinization properties), a progressive change was observed across the four classes of genotypes (wild type, single nulls, double nulls and triple nulls). However, for other grain properties (seed weight and protein content) and starch properties (total starch content, granule morphology and crystallinity, granule size distribution, amylose content, amylose-lipid dissociation properties), a statistically significant change only occurred for the triple nulls, indicating that all three genes had to be missing or inactive for a change to occur. These results illustrate the importance of SSIIa in controlling grain and starch properties and the importance of amylopectin fine structure in controlling starch granule properties in wheat.

Effect of waxy (Low Amylose) on Fungal Infection of Sorghum Grain.

Science.gov (United States)

Funnell-Harris, Deanna L; Sattler, Scott E; O'Neill, Patrick M; Eskridge, Kent M; Pedersen, Jeffrey F

2015-06-01

Loss of function mutations in waxy, encoding granule bound starch synthase (GBSS) that synthesizes amylose, results in starch granules containing mostly amylopectin. Low amylose grain with altered starch properties has increased usability for feed, food, and grain-based ethanol. In sorghum, two classes of waxy (wx) alleles had been characterized for absence or presence of GBSS: wx(a) (GBSS(-)) and wx(b) (GBSS(+), with reduced activity). Field-grown grain of wild-type; waxy, GBSS(-); and waxy, GBSS(+) plant introduction accessions were screened for fungal infection. Overall, results showed that waxy grains were not more susceptible than wild-type. GBSS(-) and wild-type grain had similar infection levels. However, height was a factor with waxy, GBSS(+) lines: short accessions (wx(b) allele) were more susceptible than tall accessions (undescribed allele). In greenhouse experiments, grain from accessions and near-isogenic wx(a), wx(b), and wild-type lines were inoculated with Alternaria sp., Fusarium thapsinum, and Curvularia sorghina to analyze germination and seedling fitness. As a group, waxy lines were not more susceptible to these pathogens than wild-type, supporting field evaluations. After C. sorghina and F. thapsinum inoculations most waxy and wild-type lines had reduced emergence, survival, and seedling weights. These results are valuable for developing waxy hybrids with resistance to grain-infecting fungi.

Encapsulating fatty acid esters of bioactive compounds in starch

Science.gov (United States)

Lay Ma, Ursula Vanesa

Interest in the use of many bioactive compounds in foods is growing in large part because of the apparent health benefits of these molecules. However, many of these compounds can be easily degraded during processing, storage, or their passage through the gastrointestinal tract before reaching the target site. In addition, they can be bitter, acrid, or astringent, which may negatively affect the sensory properties of the product. Encapsulation of these molecules may increase their stability during processing, storage, and in the gastrointestinal tract, while providing controlled release properties. The ability of amylose to form inclusion complexes and spherulites while entrapping certain compounds has been suggested as a potential method for encapsulation of certain molecules. However, complex formation and spherulitic crystallization are greatly affected by the type of inclusion molecules, type of starch, and processing conditions. The objectives of the present investigation were to: (a) study the effect of amylose, amylopectin, and intermediate material on spherulite formation and its microstructure; (b) investigate the formation of amylose and high amylose starch inclusion complexes with ascorbyl palmitate, retinyl palmitate, and phytosterol esters; (c) evaluate the ability of spherulites to form in the presence of fatty acid esters and to entrap ascorbyl palmitate, retinyl palmitate, and phytosterol esters; and (d) evaluate the effect of processing conditions on spherulite formation and fatty acid ester entrapment. Higher ratios of linear to branched molecules resulted in the formation of more and rounder spherulites with higher heat stability. In addition to the presence of branches, it appears that spherulitic crystallization is also affected by other factors, such as degree of branching, chain length, and chain length distribution. Amylose and Hylon VII starch formed inclusion complexes with fatty acid esters of ascorbic acid, retinol, or phytosterols

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.

Correlation of pasting behaviors with total phenolic compounds and starch digestibility of indigenous pigmented rice grown in upper Northern Thailand

Directory of Open Access Journals (Sweden)

Jirapa Ponjanta

2016-03-01

Full Text Available Background: Thailand has one of the most important rice genetic resources with white, light brown, brown, red, and purple rice bran colors. The latter believed to have potential for health benefits due to their phenolic content. Recently researchers have indicated that starch digestive enzymes, including salivary and pancreatic α-amylases and α-glucosidases, can be inhibited by phenolic compounds. Although pasting properties of rice flour are key determinants of quality significantly impacting the final product texture, there is no in-depth study on their correlation with phenolic compound and starch digestibility. Methods: Rice flour from twelve varieties, three from each of five bran colors (white, brown, red, and purple, were evaluated for pasting properties (RVA-3D, total phenolic compounds, amylose content, resistant starch and estimated glycemic index. Simple correlation coefficients were calculated for the relationships between pasting properties (final viscosity, breakdown, setback and pasting temperature and total phenolic compounds, resistant starch and estimated glycemic index. Results: Within each rice variety, red and purple pigmented flours had higher total phenolic compounds (TPC and more resistant starch than that of white flours. The TPC and resistant starch content of the flours ranged between 7.83- 47.3 mg/L and 2.44–10.50% respectively, and producing 60-80 of estimated glycemic index. Viscosity behavior showed that pigmented with low amylose rice had lower viscosity temperature than that of pigmented with high amylose rice flour, but higher in peak viscosity. Correlation coefficients of pasting temperature, final viscosity, break down and setback with TCP was observed to be inversely related to glycemic index. However, it was positively correlated to the resistant starch and amylose content. Conclusions: Pigmented rice flour is a better source of TPC and resistant starch which in turn provides low glycemic index. This

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

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.

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.

Starch bioengineering in Brachypodium distachyon

DEFF Research Database (Denmark)

Tanackovic, Vanja; Svensson, Jan Tommy; Buleon, A

2011-01-01

Brachypodium distachyon was recently introduced as a model plant for temperate cereals (Opanowicz et al., 2008). We aim to establish Brachypodium as a model for cereal starch metabolism. Grain starch from two lines: Bd21 and Bd21-3 are being characterized. Microscopic, chemical and structural data...... including amylopectin chain length distribution, phosphate content and amylose content provided further evidence for the close relationship to temperate cereals even though starch content and starch granule size were considerably lower than that for barley (Hordeum vulgare). Bioinformatics analyses...... in temperate cereals....

Long branch-chains of amylopectin with B-type crystallinity in rice seed with inhibition of starch branching enzyme I and IIb resist in situ degradation and inhibit plant growth during seedling development : Degradation of rice starch with inhibition of SBEI/IIb during seedling development.

Science.gov (United States)

Pan, Ting; Lin, Lingshang; Wang, Juan; Liu, Qiaoquan; Wei, Cunxu

2018-01-08

Endosperm starch provides prime energy for cereal seedling growth. Cereal endosperm with repression of starch branching enzyme (SBE) has been widely studied for its high resistant starch content and health benefit. However, in barley and maize, the repression of SBE changes starch component and amylopectin structure which affects grain germination and seedling establishment. A high resistant starch rice line (TRS) has been developed through inhibiting SBEI/IIb, and its starch has very high resistance to in vitro hydrolysis and digestion. However, it is unclear whether the starch resists in situ degradation in seed and influences seedling growth after grain germination. In this study, TRS and its wild-type rice cultivar Te-qing (TQ) were used to investigate the seedling growth, starch property changes, and in situ starch degradation during seedling growth. The slow degradation of starch in TRS seed restrained the seedling growth. The starch components including amylose and amylopectin were simultaneously degraded in TQ seeds during seedling growth, but in TRS seeds, the amylose was degraded faster than amylopectin and the amylopectin long branch-chains with B-type crystallinity had high resistance to in situ degradation. TQ starch was gradually degraded from the proximal to distal region of embryo and from the outer to inner in endosperm. However, TRS endosperm contained polygonal, aggregate, elongated and hollow starch from inner to outer. The polygonal starch similar to TQ starch was completely degraded, and the other starches with long branch-chains of amylopectin and B-type crystallinity were degraded faster at the early stage of seedling growth but had high resistance to in situ degradation during TRS seedling growth. The B-type crystallinity and long branch-chains of amylopectin in TRS seed had high resistance to in situ degradation, which inhibited TRS seedling growth.

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 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.

Physicochemical Characteristics of Artificial Rice from Composite Flour: Modified Cassava Starch, Canavalia ensiformis and Dioscorea esculenta

Science.gov (United States)

Sumardiono, Siswo; Pudjihastuti, Isti; Handayani, Noer Abyor; Kusumayanti, Heny

2018-02-01

Indonesia is the third largest country on the global paddy rice production and also considered as a rice importer. Even, Indonesia has the biggest per capita consumption of paddy rice (140 kg of paddy rice per person per year). Product diversification using local commodities. Artificial rice is potential to be developed as a new value product using different types of grains. It is one of appropriate solutions for reducing imported rice rate. Artificial rice was produced using high nutrition composite flours (modified cassava starch, corn, Canavalian ensiformis, and Dioscorea esculenta). This study consists of three main stages, preparation of composite flour, formulation, and artificial rice production using hot extruder capacity 10 kg/day. The objectives of this studies were to investigate some formulation in compare with commercial paddy rice. Artificial rice has been successfully conducted using prototype of hot extruder with the temperature 95°C. Physical analyses (color and water absorption) were carried out to artificial rice product and commercial paddy rice. Chemical analyses (nutrition and amylose content) of product will be also presented in this study. The best formulation of artificial rice was achieved in 80% modified cassava starch, 10% Canavalian ensiformis, and 10% Dioscorea esculenta, respectively.

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

Directory of Open Access Journals (Sweden)

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.

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

International Nuclear Information System (INIS)

Silva, Leonardo G. Andrade e; Poveda, Patricia N.S.; Rezende, Maira L.; Rosa, Derval S.

2009-01-01

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 α-amylase, the irradiated samples presented faster biodegradation than the references non irradiated. The blend of aromatic aliphatic copolyester with corn starch (Ecobras R ) irradiated presented a bigger biodegradability than the aromatic aliphatic copolyester (Ecoflex R ) film in both methods studied. (author)

Increased Butyrate Production During Long-Term Fermentation of In Vitro-Digested High Amylose Cornstarch Residues with Human Feces.

Science.gov (United States)

Li, Li; Jiang, Hongxin; Kim, Hyun-Jung; Yum, Man-Yu; Campbell, Mark R; Jane, Jay-Lin; White, Pamela J; Hendrich, Suzanne

2015-09-01

An in vitro semi-continuous long-term (3 wk) anaerobic incubation system simulating lower gut fermentation was used to determine variability in gut microbial metabolism between 4 predigested high amylose-resistant starch residues (SR): SRV, SRVI, SRVII, and SRGEMS in human fecal samples. Subjects participated twice, 5 mo apart: 30 in Phase I (15 lean, 9 overweight and 6 obese), 29 in Phase II (15 lean, 9 overweight, 5 obese); 13 of 15 lean subjects participated in both phases. Of the 4 SRs, SRV displayed the highest gelatinization temperature, peak temperature, enthalpy changes, and the least digestibility compared with the other SRs. In both phases, compared with blank controls, all SRs increased butyrate ∼2-fold which stabilized at week 2 and only SRV caused greater propionate concentration (∼30%) after 3 wk which might have been partly mediated by its lesser digestibility. Fecal samples from lean and overweight/obese subjects incubated with SRs showed similar short-chain fatty acid production across both time points, which suggests that resistant starch may benefit individuals across BMIs. © 2015 Institute of Food Technologists®

Maize starch biphasic pasting curves

CSIR Research Space (South Africa)

Nelles, EM

2000-05-01

Full Text Available (150–500 rev/min). The second pasting peak is attributed to the formation of complexes between amylose and low levels of lipid present in maize starch. When lipid was partially removed by extraction with methanol-chloroform (1: 3 v/v), the second...

Cereal bioengineering: Amylopectin-free and hyper-phosphorylated barley starch

DEFF Research Database (Denmark)

Carciofi, Massimiliano; Shaik, Shahnoor Sultana; Jensen, Susanne Langgård

Barley lines producing grains with either amylopectin-free or hyper-phosphorylated starches were made by transgenic methods. Cereals producing these kind of starches have not been reported before. Amylopectin-free barley was generated by simultaneously silencing the three genes encoding the starch...... and T1) of transgenic grains was tenfold higher than from vector control and wild type grains. Amylose content was not affected in hyper-phosphorylated grains. Hyper-phosphorylated starch granules had several pores on the surfaces, similar to pores seen on enzymatically semi-degraded granules...

Cereal bioengineering: Amylopectin-free and hyper-phosphorylated barley starch

DEFF Research Database (Denmark)

Carciofi, Massimiliano; Shaik, Shahnoor Sultana; Jensen, Susanne Langgård

2011-01-01

Barley lines producing grains with either amylopectin-free or hyper-phosphorylated starches were made by transgenic methods. Cereals producing these kind of starches have not been reported before. Amylopectin-free barley was generated by simultaneously silencing the three genes encoding the starch...... and T1) of transgenic grains was tenfold higher than from vector control and wild type grains. Amylose content was not affected in hyper-phosphorylated grains. Hyper-phosphorylated starch granules had several pores on the surfaces, similar to pores seen on enzymatically semi-degraded granules...

Impact of local hydrothermal treatment during bread baking on soluble amylose, firmness, amylopectin retrogradation and water mobility during bread staling.

Science.gov (United States)

Besbes, Emna; Le Bail, Alain; Seetharaman, Koushik

2016-01-01

The impact of hydrothermal processing undergone by bread dough during baking on the degree of starch granule disruption, on leaching of soluble amylose, on water mobility, on firmness and on amylopectin retrogradation during staling has been investigated. Two heating rates during baking have been considered (4.67 and 6.31 °C/min) corresponding respectively to baking temperature of 220 and 240 °C. An increase in firmness and in the amount of retrogradated amylopectin accompanied by a decrease in freezable water has been observed during staling. Although a lower heating rate yielded in larger amount of retrogradated amylopectin retrogradation, it resulted in a lower firmness. Additionally, the amount of soluble amylose and the relaxation times of water measured by Nuclear Magnetic Resonance NMR (T20, T21 and T22) decreased during staling. It was demonstrated that the amount of soluble amylose was higher for bread crumb baked at lower heating rate, indicating that an increasing amount of amylose is leached outside the starch granules. This was corresponding to a greater amount of retrograded amylopectin during staling. Moreover, it was found that the degree of gelatinization differs locally in a same bread slice between the top, the centre and the bottom locations in the crumb. This was attributed to the differences in kinetics of heating, the availability of water during baking and the degree of starch granule disruption during baking. Based on first order kinetic model, it was found that staling kinetics were faster for samples baked at higher heating rate.

Preparation And Physicochemical Properties of Octenyl Succinic Anhydride (OSA) Modified Sago Starch

International Nuclear Information System (INIS)

Nur Farhana Zainal Abiddin; Anida Yusoff; Noorlaila Ahmad

2016-01-01

Starch from sago (Metroxylon sagu) was esterified with octenyl succinic anhydride (OSA) in order to regulate its shortcoming by adding amphiphilic properties. The objective of this work is to determine the physicochemical properties of native sago and OSA sago starches. The OSA sago starch was produced according to the optimum condition generated via response surface methodology (RSM) with 5.00 % OSA at pH 7.20 and a reaction time of 9.65 hours. The esterified sago starch gives a degree of substitution (DS) value of 0.012. The physicochemical properties of OSA sago starch was determined by measuring the amylose content, laser diffraction particle size analyzer, scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR). The amylose content for OSA sago starch was found to be reduced after esterification reaction. The particle size of OSA sago starch was found to increase significantly (p<0.05) compared to their native starches. Scanning electron microscopy (SEM) revealed that OSA starch developed slightly rough surface and their edges lost some definition. FT-IR spectroscopy shows that there was appearance of new absorption correspond to ester carbonyl group (1717 cm -1 ) and carboxylate RCOO- (1569 cm -1 ). This study showed that the physicochemical properties of modified starches were influenced not only by DS but also on the botanical origin of the starches. (author)

Lytic polysaccharide monooxygenases and other oxidative enzymes are abundantly secreted by Aspergillus nidulans grown on different starches

DEFF Research Database (Denmark)

Nekiunaite, Laura; Arntzen, Magnus Ø.; Svensson, Birte

2016-01-01

of Aspergillus nidulans grown on cereal starches from wheat and high-amylose (HA) maize, as well as legume starch from pea for 5 days. Aspergillus nidulans grew efficiently on cereal starches, whereas growth on pea starch was poor. The secretomes at days 3-5 were starch-type dependent as also reflected...... by amylolytic activity measurements. Nearly half of the 312 proteins in the secretomes were carbohydrate-active enzymes (CAZymes), mostly glycoside hydrolases (GHs) and oxidative auxiliary activities (AAs). The abundance of the GH13 α-amylase (AmyB) decreased with time, as opposed to other starch...

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.

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.

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)

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

Effect of Gamma Irradiation on the Physicochemical and Functional Properties of Cassava Starch

International Nuclear Information System (INIS)

Asare, I.K.

2011-10-01

Cassava (Manihot esculanta Crantz) is popularly consumed as a staple food crop in many tropical countries in Africa, South America and Asia. In Africa the crop has been recognized as more than a subsistence crop. The crop is very important and commercially serves as a raw material for industries with significant effect on the economy of a country. Cassava roots contain high starch content and approximately half of the total roots produced is used for the production of starch for industrial purposes. Limitation to utilization of cassava roots by processors is due to its high perishability and bulkness, while native starches are structurally too weak and funtionally restricted for a wide variety of industrial applications. The objective of the project was to determine the effect of gamma irradiation as a modifying agent on native starch from three cassava varieties namely Ankra, Bosome nsia and TME419. Gamma radiation doses applied ranged between 0 - 20kGy and changes in physicochemical, functional and pasting indices of the starch were measured. Physicochemical indices measured were moisture content, amylose content, carbohydrate content, pH, ash content, fat content, protein content and L*a*b* values. Functional indices mesured were water absorption capacity, solubility index, bulk density, swelling power, fat absorption capacity, emulsion capacity, emulsion stability and least gelation concentration. Pasting indices measured were gelatinzation temperature, peak viscosity, viscosity at 92 degrees C and 50 degrees C, breakdown viscosity and setback viscosity. The pH, amylose content, carbohydrate content and ash content of native starch from Ankra, Bosome nsia and TME 419 were respectively 8.06, 7.80 and 7.18, 17.62%, 19.46% and 23.54%, 56.11%, 52.43% and 35.70%, 0.11%, 0.19% and 0.12%. The water absortion capacity and least gelation concentration of native starch from Ankra, Bosome nsia and TME 419 were 12.3%, 13.0% and 10.0%, respectively, least gelation

Mammalian mucosal α-glucosidases coordinate with α-amylase in the initial starch hydrolysis stage to have a role in starch digestion beyond glucogenesis.

Science.gov (United States)

Dhital, Sushil; Lin, Amy Hui-Mei; Hamaker, Bruce R; Gidley, Michael J; Muniandy, Anbuhkani

2013-01-01

Starch digestion in the human body is typically viewed in a sequential manner beginning with α-amylase and followed by α-glucosidase to produce glucose. This report indicates that the two enzyme types can act synergistically to digest granular starch structure. The aim of this study was to investigate how the mucosal α-glucosidases act with α-amylase to digest granular starch. Two types of enzyme extracts, pancreatic and intestinal extracts, were applied. The pancreatic extract containing predominantly α-amylase, and intestinal extract containing a combination of α-amylase and mucosal α-glucosidase activities, were applied to three granular maize starches with different amylose contents in an in vitro system. Relative glucogenesis, released maltooligosaccharide amounts, and structural changes of degraded residues were examined. Pancreatic extract-treated starches showed a hydrolysis limit over the 12 h incubation period with residues having a higher gelatinization temperature than the native starch. α-Amylase combined with the mucosal α-glucosidases in the intestinal extract showed higher glucogenesis as expected, but also higher maltooligosaccharide amounts indicating an overall greater degree of granular starch breakdown. Starch residues after intestinal extract digestion showed more starch fragmentation, higher gelatinization temperature, higher crystallinity (without any change in polymorph), and an increase of intermediate-sized or small-sized fractions of starch molecules, but did not show preferential hydrolysis of either amylose or amylopectin. Direct digestion of granular starch by mammalian recombinant mucosal α-glucosidases was observed which shows that these enzymes may work either independently or together with α-amylase to digest starch. Thus, mucosal α-glucosidases can have a synergistic effect with α-amylase on granular starch digestion, consistent with a role in overall starch digestion beyond their primary glucogenesis function.

Mammalian mucosal α-glucosidases coordinate with α-amylase in the initial starch hydrolysis stage to have a role in starch digestion beyond glucogenesis.

Directory of Open Access Journals (Sweden)

Sushil Dhital

Full Text Available Starch digestion in the human body is typically viewed in a sequential manner beginning with α-amylase and followed by α-glucosidase to produce glucose. This report indicates that the two enzyme types can act synergistically to digest granular starch structure. The aim of this study was to investigate how the mucosal α-glucosidases act with α-amylase to digest granular starch. Two types of enzyme extracts, pancreatic and intestinal extracts, were applied. The pancreatic extract containing predominantly α-amylase, and intestinal extract containing a combination of α-amylase and mucosal α-glucosidase activities, were applied to three granular maize starches with different amylose contents in an in vitro system. Relative glucogenesis, released maltooligosaccharide amounts, and structural changes of degraded residues were examined. Pancreatic extract-treated starches showed a hydrolysis limit over the 12 h incubation period with residues having a higher gelatinization temperature than the native starch. α-Amylase combined with the mucosal α-glucosidases in the intestinal extract showed higher glucogenesis as expected, but also higher maltooligosaccharide amounts indicating an overall greater degree of granular starch breakdown. Starch residues after intestinal extract digestion showed more starch fragmentation, higher gelatinization temperature, higher crystallinity (without any change in polymorph, and an increase of intermediate-sized or small-sized fractions of starch molecules, but did not show preferential hydrolysis of either amylose or amylopectin. Direct digestion of granular starch by mammalian recombinant mucosal α-glucosidases was observed which shows that these enzymes may work either independently or together with α-amylase to digest starch. Thus, mucosal α-glucosidases can have a synergistic effect with α-amylase on granular starch digestion, consistent with a role in overall starch digestion beyond their primary

Mammalian Mucosal α-Glucosidases Coordinate with α-Amylase in the Initial Starch Hydrolysis Stage to Have a Role in Starch Digestion beyond Glucogenesis

Science.gov (United States)

Dhital, Sushil; Lin, Amy Hui-Mei; Hamaker, Bruce R.; Gidley, Michael J.; Muniandy, Anbuhkani

2013-01-01

Starch digestion in the human body is typically viewed in a sequential manner beginning with α-amylase and followed by α-glucosidase to produce glucose. This report indicates that the two enzyme types can act synergistically to digest granular starch structure. The aim of this study was to investigate how the mucosal α-glucosidases act with α-amylase to digest granular starch. Two types of enzyme extracts, pancreatic and intestinal extracts, were applied. The pancreatic extract containing predominantly α-amylase, and intestinal extract containing a combination of α-amylase and mucosal α-glucosidase activities, were applied to three granular maize starches with different amylose contents in an in vitro system. Relative glucogenesis, released maltooligosaccharide amounts, and structural changes of degraded residues were examined. Pancreatic extract-treated starches showed a hydrolysis limit over the 12 h incubation period with residues having a higher gelatinization temperature than the native starch. α-Amylase combined with the mucosal α-glucosidases in the intestinal extract showed higher glucogenesis as expected, but also higher maltooligosaccharide amounts indicating an overall greater degree of granular starch breakdown. Starch residues after intestinal extract digestion showed more starch fragmentation, higher gelatinization temperature, higher crystallinity (without any change in polymorph), and an increase of intermediate-sized or small-sized fractions of starch molecules, but did not show preferential hydrolysis of either amylose or amylopectin. Direct digestion of granular starch by mammalian recombinant mucosal α-glucosidases was observed which shows that these enzymes may work either independently or together with α-amylase to digest starch. Thus, mucosal α-glucosidases can have a synergistic effect with α-amylase on granular starch digestion, consistent with a role in overall starch digestion beyond their primary glucogenesis function. PMID

On the possibility to affect the course of glycaemia, insulinaemia, and perceived hunger/satiety to bread meals in healthy volunteers.

Science.gov (United States)

Ekström, Linda M N K; Björck, Inger M E; Ostman, Elin M

2013-04-25

Frequent hyperglycaemia is associated with oxidative stress and subclinical inflammation, and thus increased risk of cardiovascular disease. Possibilities of modulating glycaemia, insulinaemia and perceived satiety for bread products were investigated, with emphasis on the course of glycaemia expressed as a glycaemic profile (defined as the duration of the glucose curve above the fasting concentration divided by the incremental glucose peak). For this purpose white wheat bread was supplemented with whole grain corn flour with an elevated amylose content and different types and levels of guar gum. The bread products were characterised in vitro for release of starch degradation products and content of resistant starch. Fibre related fluidity following enzyme hydrolysis was also studied. By combining medium weight guar gum and whole grain corn flour with an elevated amylose content, the course of glycaemia, insulinaemia and subjective appetite ratings were improved compared to the reference white wheat bread. In addition, the combination beneficially influenced the content of resistant starch. Fluidity measurements showed potential to predict the glycaemic profile.

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.

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

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)

Physicochemical properties of maca starch.

Science.gov (United States)

Zhang, Ling; Li, Guantian; Wang, Sunan; Yao, Weirong; Zhu, Fan

2017-03-01

Maca (Lepidium meyenii Walpers) is gaining research attention due to its unique bioactive properties. Starch is a major component of maca roots, thus representing a novel starch source. In this study, the properties of three maca starches (yellow, purple and black) were compared with commercially maize, cassava, and potato starches. The starch granule sizes ranged from 9.0 to 9.6μm, and the granules were irregularly oval. All the maca starches presented B-type X-ray diffraction patterns, with the relative degree of crystallinity ranging from 22.2 to 24.3%. The apparent amylose contents ranged from 21.0 to 21.3%. The onset gelatinization temperatures ranged from 47.1 to 47.5°C as indicated by differential scanning calorimetry. Significant differences were observed in the pasting properties and textural parameters among all of the studied starches. These characteristics suggest the utility of native maca starch in products subjected to low temperatures during food processing and other industrial applications. Copyright © 2016 Elsevier Ltd. 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.

Starch bioengineering affects cereal grain germination and seedling establishment

DEFF Research Database (Denmark)

Shaik, Shahnoor Sultana; Carciofi, Massimiliano; Martens, Helle Juel

2014-01-01

Cereal grain germination is central for plant early development, and efficient germination has a major role in crop propagation and malting. Endosperm starch is the prime energy reserve in germination and seedling establishment. In this study, it was hypothesized that optimized starch granule...... structure, and not only the endosperm starch content per se, is important for germination and seedling establishment. For that purpose, wild-type (WT), and specifically engineered degradable hyperphosphorylated (HP) starch and more resistant amylose-only (AO) starch barley lines were used. The transgenics...... showed no severe phenotypes and the WT and HP lines degraded the starch similarly, having 30% residual starch after 12 d of germination. However, the AO line showed significant resistance to degradation, having 57% residual starch. Interestingly, protein and β-glucan (BG) degradation was stimulated...

Physicochemical Characteristics of Artificial Rice from Composite Flour: Modified Cassava Starch, Canavalia ensiformis and Dioscorea esculenta

Directory of Open Access Journals (Sweden)

Sumardiono Siswo

2018-01-01

Full Text Available Indonesia is the third largest country on the global paddy rice production and also considered as a rice importer. Even, Indonesia has the biggest per capita consumption of paddy rice (140 kg of paddy rice per person per year. Product diversification using local commodities. Artificial rice is potential to be developed as a new value product using different types of grains. It is one of appropriate solutions for reducing imported rice rate. Artificial rice was produced using high nutrition composite flours (modified cassava starch, corn, Canavalian ensiformis, and Dioscorea esculenta. This study consists of three main stages, preparation of composite flour, formulation, and artificial rice production using hot extruder capacity 10 kg/day. The objectives of this studies were to investigate some formulation in compare with commercial paddy rice. Artificial rice has been successfully conducted using prototype of hot extruder with the temperature 95°C. Physical analyses (color and water absorption were carried out to artificial rice product and commercial paddy rice. Chemical analyses (nutrition and amylose content of product will be also presented in this study. The best formulation of artificial rice was achieved in 80% modified cassava starch, 10% Canavalian ensiformis, and 10% Dioscorea esculenta, respectively.

Glycemic potency of muffins made with wheat, rice, corn, oat and barley flours: a comparative study between in vivo and in vitro.

Science.gov (United States)

Soong, Yean Yean; Quek, Rina Yu Chin; Henry, Christiani Jeyakumar

2015-12-01

Muffins made with wheat flour are a popular snack consumed in western and emerging countries. This study aimed to examine the content of amylose, glycemic response (GR) and glycemic index (GI) of muffins baked with refined wheat and rice flours, as well as wholegrain corn, oat and barley flours. This study adopted a randomized, controlled, crossover, non-blind design. Twelve healthy participants consumed wheat, rice, corn, oat and barley muffins once and the reference glucose solution three times in a random order on non-consecutive day. Capillary blood samples were taken every 15 min in the first 60 min and every 30 min for the remaining 60 min for blood glucose analysis. The Megazyme amylose/amylopectin assay procedure was employed to measure amylose content. The GR elicited from the consumption of wheat, rice and corn muffins was comparable between these samples but significantly greater when compared with oat and barley muffins. Consumption of wholegrain muffins, apart from corn muffin, blunted postprandial GR when compared with muffins baked with refined cereal flours. Muffins baked with wheat, rice, corn, oat and barley flours gave rise to GI values of 74, 79, 74, 53 and 55, respectively. The content of amylose was significantly higher in corn, oat and barley muffins than wheat and rice muffins. The greater content of amylose and fibre may play a part in the reduced glycemic potency of oat and barley muffins. Wheat flour can be substituted with oat and barley flours for healthier muffins and other bakery products.

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.

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.

Starch-lipid inclusion complexes for aerogel formation

Science.gov (United States)

Recently we reported that aqueous slurries of starch can be excess steam jet-cooked and blended with aqueous solutions of fatty acid salts to produce inclusion complexes between amylose and the fatty acid salt. These complexes can be simply prepared on large scale using commercially available steam ...

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....

Sensory and Textural Characteristics of Noodle Made of Ganyong Flour (Canna edulis Kerr.) and Arenga Starch (Arenga pinnata Merr.)

Science.gov (United States)

Herawati, ERN; Ariani, D.; Miftakhussolikhah; Yosieto, E.; Angwar, M.; Pranoto, Y.

2017-12-01

Ganyong (Canna edulis Kerr) is a local tuber which highest amount of starch content, but has not been fully utilized well at present. One way to improve the usefulness of canna is to process it into noodle, but it needs arenga starch which has high amylose content. The aim of this research was to study the sensory and textural properties of noodle made from canna flour and arenga starch. Research methodologies consist of: (i) characterization of canna flour and arenga starch, (ii) noodle production, and (iii) characterization sensory and textural properties of the noodle. Noodle was made with five ratio variations of canna flour and arenga starch, i.e. 100:0; 75:25; 50:50; 25:75; and 0:100. Sensory analysis was done by hedonic scoring method with attributes : color, stickiness, elasticity, firmness, surface smoothness and overall liking. Textural properties analyses consist of tensile strength, elongation, and stickiness measurements. The results showed that canna flour and arenga starch can be used in noodle making process. Noodle with 25% of canna flour was the most favored product and has the best textural properties. Factors which affect textural properties of product are the amylose and amylopectin amount in each starch. Tensile strength, elongation, and stickiness measurements of noodle with 25% of canna flour were 0,13 N; 41,61%; and 0,0115N respectively.

Effect of Punica granatum peel extracts on antimicrobial properties in Walnut shell cellulose reinforced Bio-thermoplastic starch films from cashew nut shells.

Science.gov (United States)

Harini, K; Chandra Mohan, C; Ramya, K; Karthikeyan, S; Sukumar, M

2018-03-15

The main aim of the present study is to extract and characterize cashew nut shell (CNS) starch and walnut shell cellulose (WNC) for development of cellulose reinforced starch films. Moreover, the extraction and characterization of pomegranate peel extract, for incorporation with CNS-WNC films, was investigated. CNS starch was examined to be a moderate amylose starch with 26.32 ± 0.43% amylose content. Thermal degradation temperature of CNS starch was found to be 310 °C. Walnut shell cellulose was found to have high crystallinity index of 72%, with two thermal degradation temperatures of 319 °C and 461 °C. 2% WN cellulose reinforced CNS starch films were examined to have good oxygen transfer rate, mechanical and physical properties. Thermal degradation temperature of CNS-WNC starch films were found to be at the range of 298-302 °C. Surface roughness of CNS-WNC starch films were found to be increasing with increase in concentration of cellulose in films. Hydroxymethylfurfurole, Benzene, 2-methoxy-1,3,4-trimethyl and 1,2,3-Propanetriol, 1-acetate were found to be major active compounds present in hydrophilic extracts of Punica granatum peels. 2% WN cellulose reinforced starch films infused with hydrophilic active compounds of pomegranate peel was examined to be having good active package properties. Copyright © 2018 Elsevier Ltd. All rights reserved.

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.

Rheological and microstructural properties of Irradiated starch

International Nuclear Information System (INIS)

Atrous Turki, Hager

2011-01-01

Gamma irradiation ia s fast and efficient method to improve the functional properties of straches. Wheat and potato starches were submitted, in the present study, at 3,5,10 and 20 kGy radiation dose. The changes induced by irradiation on the rheological properties of these starches showed a decrease in the viscosity with increasing radiation dose. Chemicals bond's hydrolysis has been induced by free radicals that have been identified by EPR. Wheat starch presents five EPR signals after irradiation, whiles potato starch has a weak EPR signal. On the other hand, irradiation caused decrease in amylose content. This decrease is more pronounced in potato starch. Dry irradiated starch's MEB revealed no change in the shape, size and distribution of the granules. While, the observation of wheat starch allowed the complete disappearance of the granular structure and the dissolution of its macromolecules after irradiation which justifies the significant decrease in wheat starch's viscosity irradiated at 20 kGy.

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...

Concerted suppression of all starch branching enzyme genes in barley produces amylose-only starch granules

DEFF Research Database (Denmark)

Carciofi, Massimiliano; Blennow, Andreas; Jensen, Susanne L

2012-01-01

to glucose and rapidly absorbed in the small intestine. But a portion of dietary starch, termed "resistant starch" (RS) escapes digestion and reaches the large intestine, where it is fermented by colonic bacteria producing short chain fatty acids (SCFA) which are linked to several health benefits. The RS...

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.

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

Directory of Open Access Journals (Sweden)

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

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

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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.

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.

Comparative study on resistant starch, amilose content and glycaemic index after precooked process in white rice

Science.gov (United States)

Pratiwi, V. N.

2018-03-01

Rice is a staple food and regarded as a useful carbohydrate source. In general rice is high in glycaemic index (GI) and low colonic fermentation. People are aware of the alterations in blood glucose levels or glycaemic index after consuming rice. Resistant starch (RS) and amylose content play an important role in controlling GI. GI and RS content have been established as important indicators of starch digestibility. The aim of this study was to determine the precooked process with hydrothermal (boiling at 80°C, 10 minutes) and cooling process with low temperature (4°C, 1 h) to increase potential content of RS and decrease of glycaemic index of white rice. There were two stages of this research, 1) preparation of white rice with precooked process; 2) analysis of precooked white rice characteristics (resistant starch, amylose content, and estimated glycaemic index). The result of analysis on precooked white rice showed an increased RS content (1.11%) and white rice (0.99%), but the difference was not statistically significant. The amylose content increased significantly after precooked process in white rice (24.70%) compared with white rice (20.89%). Estimated glycaemic index (EGI) decreased after precooked proses (65.63%) but not significant as compared to white rice (66.47%). From the present study it was concluded that precooked process had no significant impact on increasing RS and decreasing EGI of white rice. This may be due to the relatively short cooling time (1hour) in 4°C.

The activity of barley alpha-amylase on starch granules is enhanced by fusion of a starch binding domain from Aspergillus niger glucoamylase

DEFF Research Database (Denmark)

Juge, N.; Nøhr, J.; Le Gal-Coëffet, M.-F.

2006-01-01

High affinity for starch granules of certain amylolytic enzymes is mediated by a separate starch binding domain (SBD). In Aspergillus niger glucoamylase (GA-I), a 70 amino acid O-glycosylated peptide linker connects SBD with the catalytic domain. A gene was constructed to encode barley alpha......-amylase 1 (AMY1) fused C-terminally to this SBD via a 37 residue GA-I linker segment. AMY1-SBD was expressed in A. niger, secreted using the AMY1 signal sequence at 25 mg x L(-1) and purified in 50% yield. AMY1-SBD contained 23% carbohydrate and consisted of correctly N-terminally processed multiple forms...... in A. niger). AMY1-SBD showed a 2-fold increased activity for soluble starch at low (0.5%) but not at high (1%) concentration. AMY1-SBD hydrolysed amylose DP440 with an increased degree of multiple attack of 3 compared to 1.9 for rAMY1. Remarkably, at low concentration (2 nM), AMY1-SBD hydrolysed...

High resolution melting analysis for the detection of EMS induced mutations in wheat SbeIIa genes

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Botticella Ermelinda

2011-11-01

Full Text Available Abstract Background Manipulation of the amylose-amylopectin ratio in cereal starch has been identified as a major target for the production of starches with novel functional properties. In wheat, silencing of starch branching enzyme genes by a transgenic approach reportedly caused an increase of amylose content up to 70% of total starch, exhibiting novel and interesting nutritional characteristics. In this work, the functionality of starch branching enzyme IIa (SBEIIa has been targeted in bread wheat by TILLING. An EMS-mutagenised wheat population has been screened using High Resolution Melting of PCR products to identify functional SNPs in the three homoeologous genes encoding the target enzyme in the hexaploid genome. Results This analysis resulted in the identification of 56, 14 and 53 new allelic variants respectively for SBEIIa-A, SBEIIa-B and SBEIIa-D. The effects of the mutations on protein structure and functionality were evaluated by a bioinformatic approach. Two putative null alleles containing non-sense or splice site mutations were identified for each of the three homoeologous SBEIIa genes; qRT-PCR analysis showed a significant decrease of their gene expression and resulted in increased amylose content. Pyramiding of different single null homoeologous allowed to isolate double null mutants showing an increase of amylose content up to 21% compared to the control. Conclusion TILLING has successfully been used to generate novel alleles for SBEIIa genes known to control amylose content in wheat. Single and double null SBEIIa genotypes have been found to show a significant increase in amylose content.

Chemical characteristic and functional properties of arenga starch-taro (Colocasia esculanta L.) flour noodle with turmeric extracts addition

Science.gov (United States)

Ervika Rahayu N., H.; Ariani, Dini; Miftakhussolikhah, E., Maharani P.; Yudi, P.

2017-01-01

Arenga starch-taro (Colocasia esculanta L.) flour noodle is an alternative carbohydrate source made from 75% arenga starch and 25% taro flour, but it has a different color with commercial noodle product. The addition of natural color from turmeric may change the consumer preference and affect chemical characteristic and functional properties of noodle. This research aims to identify chemical characteristic and functional properties of arenga starch-taro flour noodle with turmeric extract addition. Extraction was performed using 5 variances of turmeric rhizome (0.06; 0.12; 0.18; 0.24; and 0.30 g (fresh weight/ml water). Then, noodle was made and chemical characteristic (proximate analysis) as well as functional properties (amylose, resistant starch, dietary fiber, antioxidant activity) were then evaluated. The result showed that addition of turmeric extract did not change protein, fat, carbohydrate, amylose, and resistant starch content significantly, while antioxidant activity was increased (23,41%) with addition of turmeric extract.

Physico-chemical properties of starches isolated from potato cultivars grown in soils with different phosphorus availability.

Science.gov (United States)

Leonel, Magali; Carmo, Ezequiel L; Fernandes, Adalton M; Franco, Célia M L; Soratto, Rogério P

2016-04-01

Starch is the major component of potato tubers, amounting approximately to 150-200 g kg (-1) of the tuber weight. Starch is considered to be a major factor for the functionality of the potato in food applications. This study evaluated the physical characteristics of potato starches isolated from tubers of different potato cultivars grown in soil with three levels of phosphorus (P) availability. All potatoes were growing according the same method. The starches were isolated by physical methods and the samples were analyzed for the amylose, P content, paste properties (RVA) and thermal properties of gelatinization and retrogradation (DSC). Experimental data were analyzed considering the potato cultivars and the three soil P availability. For all measured parameters significant impact of cultivar and soil P availability was determined. Phosphorus contents in potato starches ranged from 0.252 to 0.647 g kg(-1) and amylose from 27.18 to 30.8%. Starches from different potato cultivars independent of soil showed a small range of gelatinization temperature. All starches showed low resistance heating and shear stress. The results showed the influence of growing conditions (soil P availability) and also of the differences between the potato cultivars on important characteristics of applicability of starches. © 2015 Society of Chemical Industry.

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

The biosynthesis, structure and gelatinization properties of starches from wild and cultivated African rice species (Oryza barthii and Oryza glaberrima).

Science.gov (United States)

Wang, Kai; Wambugu, Peterson W; Zhang, Bin; Wu, Alex Chi; Henry, Robert J; Gilbert, Robert G

2015-09-20

The molecular structure and gelatinization properties of starches from domesticated African rice (Oryza glaberrima) and its wild progenitor (Oryza barthii) are determined and comparison made with Asian domesticated rice (Oryza sativa), the commonest commercial rice. This suggests possible enzymatic processes contributing to the unique traits of the African varieties. These have similar starch structures, including smaller amylose molecules, but larger amounts of amylose chains across the whole amylose chain-length distribution, and higher amylose contents, than O. sativa. They also show a higher proportion of two- and three-lamellae spanning amylopectin branch chains (degree of polymerization 34-100) than O. sativa, which contributes to their higher gelatinization temperatures. Fitting amylopectin chain-length distribution with a biosynthesis-based mathematical model suggests that the reason for this difference might be because O. glaberrima and O. barthii have more active SSIIIa and/or less active SBEIIb enzymes. Copyright © 2015 Elsevier Ltd. All rights reserved.

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)

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.

Structural and molecular basis of starch viscosity in hexaploid wheat.

Science.gov (United States)

Ral, J-P; Cavanagh, C R; Larroque, O; Regina, A; Morell, M K

2008-06-11

Wheat starch is considered to have a low paste viscosity relative to other starches. Consequently, wheat starch is not preferred for many applications as compared to other high paste viscosity starches. Increasing the viscosity of wheat starch is expected to increase the functionality of a range of wheat flour-based products in which the texture is an important aspect of consumer acceptance (e.g., pasta, and instant and yellow alkaline noodles). To understand the molecular basis of starch viscosity, we have undertaken a comprehensive structural and rheological analysis of starches from a genetically diverse set of wheat genotypes, which revealed significant variation in starch traits including starch granule protein content, starch-associated lipid content and composition, phosphate content, and the structures of the amylose and amylopectin fractions. Statistical analysis highlighted the association between amylopectin chains of 18-25 glucose residues and starch pasting properties. Principal component analysis also identified an association between monoesterified phosphate and starch pasting properties in wheat despite the low starch-phosphate level in wheat as compared to tuber starches. We also found a strong negative correlation between the phosphate ester content and the starch content in flour. Previously observed associations between internal starch granule fatty acids and the swelling peak time and pasting temperature have been confirmed. This study has highlighted a range of parameters associated with increased starch viscosity that could be used in prebreeding/breeding programs to modify wheat starch pasting properties.

Computational modeling of biodegradable starch based polymer composites

Science.gov (United States)

Joshi, Sachin Sudhakar

2007-12-01

� ' position on amylose exhibited a maximal increase of 17.1 kcal/mol as compared with the starch/PPC-MA blend. Conclusions. ROM was found to be a more effective compatibilizer in improving the favorable interactions between starch and PPC as compared to MA. The ' á ' position was found to be the most favorable attachment point of ROM to amylose for stable blend formation with PPC.

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

Effect of physico-chemical starch properties on bread quality and ageing (model study)

International Nuclear Information System (INIS)

Gambus, H.

1997-01-01

Wheat, rye and triticale starches, both native and those subjected to: segregation according to small granules (type B) and the large ones (type A), defatting with n-propanol and NaOH solution and irradiation by gamma rays at doses 3 and 5 kGy, as well as oat starch were analysed to determine their basic physico-chemical properties. Then all these starches were used in test with baking model pup loaves (40 g) from artificially composed flour, according to starch-gluten system based on recipe (for 4 pup loaves): 80 g starch d.m., 20 g dry vital gluten d.m., 8 g sugar, 3 g salt, 1 g yeast and 70 cm 3 water at 30 o C. Starch was the only alternative component in baking recipes. Additionally, wheat breads of 250 g were baked, in which part of flour was replaced by wheat and triticale starch fraction of large granules, irradiated rye and wheat starches, as well as by oat starch. Pup loaves and 250 g-loaves were evaluated on the day baking and during 3-day storage. Following parameters were determined: volume, penetration and crumb moisture and content of dry matter in crust. Also, sensory scores were performed. In addition, every day water extract from the pup loaves crumbs was prepared and in it dry matter and blue value as an indicator of soluble amylose were determined as well as carbohydrate substances were identified according to molecular mass using gel chromatography. Based on the results obtained negative effects of small starch granules and of a supplement of oat starch on bread quality were found, in spite of a beneficial effect of fatty substances contained in it, on retardation of the crumb hardening process. Also, a positive share of starch phospholipids was ascertained, not only in the retardation of amylose retrogradation but also in stabilization of crumb pores. It was observed that intensity of amylose retrogradation in crumb is determined by both the content of fatty substances in starch granules and the ratio of bound water by starch and protein

The impact of germination on the characteristics of brown rice flour and starch.

Science.gov (United States)

Xu, Jie; Zhang, Hui; Guo, Xiaona; Qian, Haifeng

2012-01-30

In recent years, germinated brown rice as a functional food has received great attention with its improved sensory and nutritional properties. Particularly of interest are the high levels of γ-amino butyric acid (GABA) which can be obtained during germination. However, more studies are needed to fully understand the effect of germination on the physicochemical properties of brown rice. Germination altered the chemical composition of brown rice, resulting in an increase in reducing sugar and ash content, and a reduction in amylose. Solubility, paste viscosity, transition temperatures (T(o) , T(p) and T(c) ) and percentage of retrogradation (%Retrogradation) were decreased, while swelling power and turbidity were significantly increased. Scanning electron micrographs indicated that starch granules from germinated brown rice became smaller and less homogeneous. Moreover, germination shortened the chain length of amylopectin and amylose molecules. This investigation provides information on changes in the characteristics of rice flour and rice starch during germination, leading to a better understanding on the chemistry of brown rice germination. Copyright © 2011 Society of Chemical Industry.

Significance of thermal transitions on starch digestibility and firming kinetics of restricted water mixed flour bread matrices.

Science.gov (United States)

Collar, Concha; Jiménez, Teresa; Conte, Paola; Piga, Antonio

2015-05-20

The impact of wheat (WT) flour replacement up to 45% (weight basis) by incorporation of ternary blends of teff (T), green pea (GP) and buckwheat (BW) flours on the thermal profiles of quaternary blended dough matrices have been investigated by simulating baking, cooling, and storage in differential scanning calorimeter (DSC) pans. Endothermal transitions related to suitable patterns for low and slow starch hydrolysis, softer crumb and retarded firming kinetics in blended breads include delayed temperatures for starch gelatinization, and for the dissociation of amylose-lipid complex. In addition, (a) higher stability for the amylose-lipid inclusion complex, (b) lower energy for starch gelatinization, (c) lower limiting melting enthalpy and (d) slower rate for amylopectin retrogradation meet thermal requirements for achieving suitable textural and starch digestibility features in blended breads, fulfilled by adding T/GP/BW to replace 45% of WT flour in blended dough formulations. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effect of dual modification with hydroxypropylation and cross-linking on physicochemical properties of taro starch.

Science.gov (United States)

Hazarika, Bidyut Jyoti; Sit, Nandan

2016-04-20

Dual modification of taro starch by hydroxypropylation and cross-linking was carried out and the properties of the modified starches were investigated. Two different levels of hydroxypropylation (5 and 10%) and cross-linking (0.05 and 0.10%) were used in different sequences. The amylose contents of the starch decreased due to single and dual modification. For the dual-modified starches, the swelling, solubility and clarity was found to increase with level of hydroxypropylation and decrease with level of cross-linking. The freeze-thaw stability of the dual-modified starches was also affected by the sequence of modification. The viscosities of the cross-linked and dual-modified starches were more than native and hydroxypropylated starches. The firmness of the dual-modified starches was also higher than native and single modified starches. The dual-modified starches have benefits of both type of modifications and could be used for specific purposes e.g. food products requiring high viscosity as well as freeze-thaw stability. Copyright © 2015 Elsevier Ltd. All rights reserved.

In vitro Starch Hydrolysis Rate, Physico-chemical Properties and Sensory Evaluation of Butter Cake Prepared Using Resistant Starch Type III Substituted for Wheat Flour.

Science.gov (United States)

Pongjanta, J; Utaipattanaceep, A; Naivikul, O; Piyachomkwan, K

2008-09-01

Resistant starch type III (RS III) derived from enzymatically debranched high amylose rice starch was prepared and used to make butter cake at different levels (0, 5, 10, 15 and 20%) in place of wheat flour. Physico-chemical properties, sensory evaluation, and in vitro starch hydrolysis rate of the developed butter cake were investigated. This study showed that the content of resistant starch in butter cake increased significantly (Pcake with RS III replacement had a significantly lower in vitro starch hydrolysis rate compared to the control cake (0% RS III). The rates of starch hydrolysis from 0 to 180 min digestion time for 0, 5, 10 15, and 20% RS III in place of wheat flour in butter cakes were 3.70 to 67.65%, 2.97 to 64.86%, 2.86 to 59.99%, 2.79 to 55.96 and 2.78 to 53.04% respectively. The physico-chemical properties of 5 to 10% RS III substituted with wheat flour in the butter cake were not significantly different from the control cake and were moderately accepted by panellists in the sensory evaluation test.

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.

Physico-chemical, morphological and pasting properties of starches extracted from water Chestnuts (Trapa natans from three Lakes of Kashmir, India

Directory of Open Access Journals (Sweden)

Adil Gani

2010-06-01

Full Text Available Studies on physicochemical, morphology and pasting properties of starches extracted from water chestnuts of three Lakes of Kashmir valley (Wular, Anchar and Dal Lakes were conducted to determine their application in different food products. The water chestnut starch from Dal Lake had more oval shaped granules than water chestnut starches from the Wular and the Anchar Lakes.The unique feature of the water chestnut starches were shape of starch granules which looked like horn(s protruding from the surface which did not appear in other starches already studied. Proximate analysis of water chestnut starches showed that average protein content were 0.4%, amylose 29.5 % and ash 0.007 on dry weight basis. Increase in water binding capacity, swelling power and solubility was found over a temperature range of 50-90ºC. Water chestnut starches showed an increase in syneresis during freeze thaw cycles and decline in paste clarity upon storage. Starch extracted from the water chestnuts of the Dal Lake showed higher water binding capacity, swelling, solubility, past clarity, freeze thaw stability, peak viscosity, final viscosity and lower protein content, amylose content, pasting temperature and gel firmness than starches extracted from water chestnuts of the Wular and the Anchar Lakes.

Starch characteristics of transgenic wheat (Triticum aestivum L.) overexpressing the Dx5 high molecular weight glutenin subunit are substantially equivalent to those in nonmodified wheat.

Science.gov (United States)

Beckles, Diane M; Tananuwong, Kanitha; Shoemaker, Charles F

2012-04-01

The effects of engineering higher levels of the High Molecular Weight Glutenin Dx5 subunit on starch characteristics in transgenic wheat (Triticum aestivum L.) grain were evaluated. This is important because of the interrelationship between starch and protein accumulation in grain, the strong biotechnological interest in modulating Dx5 levels and the increasing likelihood that transgenic wheat will be commercialized in the U.S. Unintended effects of Dx5 overexpression on starch could affect wheat marketability and therefore should be examined. Two controls with native levels of Dx5 were used: (i) the nontransformed Bobwhite cultivar, and (ii) a transgenic line (Bar-D) expressing a herbicide resistant (bar) gene, and they were compared with 2 transgenic lines (Dx5G and Dx5J) containing bar and additional copies of Dx5. There were few changes between Bar-D and Dx5G compared to Bobwhite. However, Dx5J, the line with the highest Dx5 protein (×3.5) accumulated 140% more hexose, 25% less starch and the starch had a higher frequency of longer amylopectin chains. These differences were not of sufficient magnitude to influence starch functionality, because granule morphology, crystallinity, amylose-to-amylopectin ratio, and the enthalpy of starch gelatinization and the amylose-lipid complex melting were similar to the control (P > 0.05). This overall similarity was borne out by Partial Least Squares-Discriminant Function Analysis, which could not distinguish among genotypes. Collectively our data imply that higher Dx5 can affect starch accumulation and some aspects of starch molecular structure but that the starches of the Dx5 transgenic wheat lines are substantially equivalent to the controls. Transgenic manipulation of biochemical pathways is an effective way to enhance food sensory quality, but it can also lead to unintended effects. These spurious changes are a concern to Government Regulatory Agencies and to those Industries that market the product. In this study we

Physical Characterization Of High Amylose/Pectin Mixtures Cross-Linked With Sodium Trimetaphosphate

International Nuclear Information System (INIS)

Carbinatto, F.M.; Cury, B.S.F.; Evangelista, R.C.

2010-01-01

Some researches have reported that pectin and high amylose mixtures presented superior mechanical properties in relation to those of the isolated polymers. In this work, mixtures at different ratios (1:4; 1:1) of pectin and high amylose were crosslinked with sodium trimetaphosphate at different degrees by varying reaction conditions. All samples were characterized by rheological and X-ray diffraction analyses. Samples without cross-linker were prepared as control. The oscillatory dynamic tests showed that all samples exhibited predominant elastic behavior, although cross-linked samples presented higher G' values, suggesting that crosslinking by phosphorylation resulted in more strength structures. The diffractograms showed that cross-linked samples underwent structural modifications that resulted in increase of crystallinity due to cross-linking process. (author)

Effect of pH on Physicochemical Properties of Cassava Starch Modification Using Ozone

Directory of Open Access Journals (Sweden)

Pudjihastuti Isti

2018-01-01

Full Text Available Nowadays, starch modification is carried out in order to change the native properties into the better ones, such as high stability, brightness, and better texture. The objectives of this study are to investigate the effect of pH on carboxyl content, swelling power, and water solubility of starch. This research was divided into two main stages, i.e. starch modification by ozone oxidation and analysis. The physicochemical properties of modified cassava starch were investigated under various reaction pH of 7-10 and the reaction time between 0-240 minutes. Reaction condition at pH 10 provided the higher value of carboxyl content and water solubility, but the lower of swelling power. This increase in solubility indicates that the modified oxidation starch readily dissolves in water, due to its small size granules and high amylose content. The significant changes of both parameters were achieved in the first 120 minutes of ozone reaction times. The graphic pattern of water solubility was in contrast with swelling power.

Physicochemical studies on starches isolated from plantain cultivars, plantain hybrids and cooking bananas

Energy Technology Data Exchange (ETDEWEB)

Eggleston, G.; Akoni, S. (International Inst. of Tropical Agriculture, Ibadan (Nigeria)); Swennen, R. (Catholic Univ. of Leuven, Heverlee (Belgium). Lab. of Tropical Husbandry)

1992-04-01

Starches from mature, unripe fruit pulp of plantain cultivars (Musa supp., AAB group) representing the wide variability in Africa, tetraploid and diploid plantain hybrids and starchy cooking bananas (Musa spp., ABB group) were isolated and characterised. In general, studies revealed very compact irregularly shaped and sized granules, with low amylose content (9.11-17.16%), highly resistant to bacterial {alpha}-amylase attack; Brabender amylograms showed very restricted swelling type patterns with great stability and negligible retrogradation. Results indicate that differences in physico-chemical properties exist amongst the three Musa fruit group starches. Plantains represent a chemical/molecular homogeneous group, but heterogeneous for granule structure. Ploidy level affected hybrid properties. ABB cooking bananas starches exhibited highly pronounced restricted swelling and high gelatinisation and pasting temperatures, indicating a more ordered, very strongly bonded granule structure; chemical and physical properties varied considerably within the ABB genotype. (orig.).

Processing stability of cross-linked starches in acid sauce applications and identification of some of the molecular factors involved

NARCIS (Netherlands)

Steeneken, P.A.M.; Woortman, A.J.J.; Oudhuis, A.A.C.M.

2011-01-01

The thickening functionality of four acetylated di-starch adipates with variations in starch source and amylose and adipate contents was evaluated in a simplified small-scale model sauce system at fourteen processing conditions with variations in temperature, shear, and pH. A processing stability

Studies on rye starch properties and modification. Pt. 1. Composition and properties of rye starch granules

Energy Technology Data Exchange (ETDEWEB)

Schierbaum, F; Radosta, S; Richter, M; Kettlitz, B [Zentralinstitut fuer Ernaehrung, Potsdam (Germany); Gernat, C [Zentralinstitut fuer Molekularbiologie, Berlin (Germany)

1991-09-01

Rye is considered as a potential raw material for starch industry. Starting from a survey of technical procedures of isolating starches from rye-flour and -grits investigations will be reported, which were performed on pilot plant- and laboratory-isolated rye starches. The present paper deals with its granule appearance and composition. A distribution of granule size between small granules ({<=} 10 {mu}m - 15%) and large granules ({>=} 11 ... {<=} 40 {mu}m = 85%) is typical for the totality of the starches. Differing distributions depend on the conditions of isolation: The entity of starch containing samples resulted from the latoratory procedures under investigation. Large-granule starch preparations were isolated in the pilot plant: The centrifuge-overflow contains the small-granule fraction which is high in impurities. Granule crystallinity amounts to 16%. The crystalline component - like in wheat and triticale starches - consists predominantly of A-polymorph - with up to 9% of the B-type. The isotherms of water exchange are of the cereal type. The contents of minor constituents largely relate to the small granule fraction which assembles the majority of crude protein, pentosans and lipids, which are difficult to remove. Lipid components in all fractions influence the results of linear chain-iodine interactions and they must be removed to proceed from apparent to absolute polysaccharide indices. The absolute amylose contents amount to {approx equal} 25% for large granule samples and to 20-21% for small granule samples. The average chain-length of iodine binding helical regions was determined with 220-240 AGU. (orig.).

Extrudates of starch-xanthan gum mixtures as affected by chemical agents and irradiation

International Nuclear Information System (INIS)

Hanna, M.A.; Chinnaswamy, R.; Gray, D.R.; Miladinov, V.D.

1997-01-01

Mixtures of starch, xanthan gum and either polyvinyl alcohol, epichlorohydrin, valeric acid or adipoyl chloride were extruded. Properties of extrudates including apparent viscosity, water solubility, water absorption indices and extrudate expansion were measured for different proportions of xanthan gum, 70% amylose starch (with or without irradiation) and chemical agents. Extrusion with chemical agents and irradiation changed physical properties of both starch and xanthan gum. Expansions of extrudates were higher than that of starch. Viscosity of extrudates increased with xanthan gum concentration. The addition of 1% (w/w) polyvinyl alcohol had the greatest effect of the chemical agents. Irradiation increased the apparent viscosity of starch-xanthan gum mixtures

In vitro amylolysis of pulse and hylon VII starches explained in terms of their composition, morphology, granule architecture and interaction between hydrolysed starch chains.

Science.gov (United States)

Maaran, S; Hoover, R; Vamadevan, V; Waduge, R N; Liu, Q

2016-02-01

The objective of this study was to understand the factors underlying the susceptibility of pulse (lablab bean, navy bean, rice bean, tepary bean, velvet bean, and wrinkled pea) and hylon VII starches towards in vitro hydrolysis by the combined action of pancreatin and amyloglucosidase. The time taken to reach an equivalent level of hydrolysis (50%) varied significantly among the starches. Changes to molecular order, crystallinity, double helical content, radial orientation of starch chains (polarized light), enthalpy and apparent amylose content during the progress of hydrolysis showed that rate and extent of hydrolysis were influenced both by the structure of the native starches at different levels (molecular, mesoscopic, microscopic) of granule organization, and by the extent of retrogradation between hydrolysed starch chains. Copyright © 2015 Elsevier Ltd. All rights reserved.

Significance of starch properties and quantity on sponge cake volume

Science.gov (United States)

We evaluated the qualitative and quantitative effects of wheat starch on sponge cake (SC) baking quality. Twenty wheat flours, including soft white and club wheat of normal, partial waxy and waxy endosperm, and hard wheat, were tested for amylose content, pasting properties, and SC baking quality. S...

Effects of cooking methods and starch structures on starch hydrolysis rates of rice.

Science.gov (United States)

Reed, Michael O; Ai, Yongfeng; Leutcher, Josh L; Jane, Jay-lin

2013-07-01

This study aimed to understand effects of different cooking methods, including steamed, pilaf, and traditional stir-fried, on starch hydrolysis rates of rice. Rice grains of 3 varieties, japonica, indica, and waxy, were used for the study. Rice starch was isolated from the grain and characterized. Amylose contents of starches from japonica, indica, and waxy rice were 13.5%, 18.0%, and 0.9%, respectively. The onset gelatinization temperature of indica starch (71.6 °C) was higher than that of the japonica and waxy starch (56.0 and 56.8 °C, respectively). The difference was attributed to longer amylopectin branch chains of the indica starch. Starch hydrolysis rates and resistant starch (RS) contents of the rice varieties differed after they were cooked using different methods. Stir-fried rice displayed the least starch hydrolysis rate followed by pilaf rice and steamed rice for each rice variety. RS contents of freshly steamed japonica, indica, and waxy rice were 0.7%, 6.6%, and 1.3%, respectively; those of rice pilaf were 12.1%, 13.2%, and 3.4%, respectively; and the stir-fried rice displayed the largest RS contents of 15.8%, 16.6%, and 12.1%, respectively. Mechanisms of the large RS contents of the stir-fried rice were studied. With the least starch hydrolysis rate and the largest RS content, stir-fried rice would be a desirable way of preparing rice for food to reduce postprandial blood glucose and insulin responses and to improve colon health of humans. © 2013 Institute of Food Technologists®

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.

Investigation of digestion Kinetics in commercial starches using in-situ small-angle neutron scattering

International Nuclear Information System (INIS)

Blazek, Jaroslav; Gilbert, Elliot Paul

2009-01-01

Full text: The digestion of starch has been the subject of many investigations, mostly involving in vitro measurement of the susceptibility of starches to attack by different enzymes, rather than measuring actual digestibility in vivo. The rate and extent of amylolytic hydrolysis of granular starches is known to vary according to botanical origin. Granule characteristics considered to influence susceptibility to attack by alpha-amylase include crystallinity, granule size and available specific surface, amylose content, porosity, structural inhomogeneities and degree of integrity. Most in-vitro studies of granular starch digestion have been limited to samples for which aliquots have been removed from the reaction mixture at various time intervals and freeze-dried to be subsequently characterized using a range of techniques. It remains unclear whether sample preparation creates artefacts in the samples. In this study, we have studied the kinetics of starch digestion of several commercial granular starches by time-resolved small-angle neutron scattering using an in-situ digestion chamber allowing, for the first time, to follow structural changes of starch in the course of digestion directly in the digestion mixture. Additionally, samples before and after digestion were studied by x-ray diffraction, small-angle x-ray scattering, differential scanning calorimetry and microscopy. Microscopy revealed that studied starches, which varied in their amylose content and digestion kinetics, followed different modes of attack The multidisciplinary approach allowed the nanostructural changes detected by small-angle scattering in the course of enzymic breakdown to be correlated with changes in crystallinity and functional properties.

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.

Black leaf streak disease affects starch metabolism in banana fruit.

Science.gov (United States)

Saraiva, Lorenzo de Amorim; Castelan, Florence Polegato; Shitakubo, Renata; Hassimotto, Neuza Mariko Aymoto; Purgatto, Eduardo; Chillet, Marc; Cordenunsi, Beatriz Rosana

2013-06-12

Black leaf streak disease (BLSD), also known as black sigatoka, represents the main foliar disease in Brazilian banana plantations. In addition to photosynthetic leaf area losses and yield losses, this disease causes an alteration in the pre- and postharvest behavior of the fruit. The aim of this work was to investigate the starch metabolism of fruits during fruit ripening from plants infected with BLSD by evaluating carbohydrate content (i.e., starch, soluble sugars, oligosaccharides, amylose), phenolic compound content, phytohormones, enzymatic activities (i.e., starch phosphorylases, α- and β-amylase), and starch granules. The results indicated that the starch metabolism in banana fruit ripening is affected by BLSD infection. Fruit from infested plots contained unusual amounts of soluble sugars in the green stage and smaller starch granules and showed a different pattern of superficial degradation. Enzymatic activities linked to starch degradation were also altered by the disease. Moreover, the levels of indole-acetic acid and phenolic compounds indicated an advanced fruit physiological age for fruits from infested plots.

Physicochemical properties of cassava starch and starch-keratin prepared biofilm

Directory of Open Access Journals (Sweden)

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

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...

Effect of acid hydrolysis on starch structure and functionality: a review.

Science.gov (United States)

Wang, Shujun; Copeland, Les

2015-01-01

Acid hydrolysis is an important chemical modification that can significantly change the structural and functional properties of starch without disrupting its granular morphology. A deep understanding of the effect of acid hydrolysis on starch structure and functionality is of great importance for starch scientific research and its industrial applications. During acid hydrolysis, amorphous regions are hydrolyzed preferentially, which enhances the crystallinity and double helical content of acid hydrolyzed starch. This review discusses current understanding of the effect of acid hydrolysis on starch structure and functionality. The effects of acid hydrolysis on amylose content, chain length distribution of amylopectin molecules, molecular and crystalline organization (including lamellar structure) and granular morphology are considered. Functional properties discussed include swelling power, gelatinization, retrogradation, pasting, gel texture, and in vitro enzyme digestibility. The paper also highlights some promising applications of acid hydrolyzed starch (starch nanocrystals) in the preparation of biodegradable nanocomposites, bio-hydrogen, and slowly digestible starch-based healthy foods.

PERUBAHAN STRUKTUR PATI GARUT (Maranta arundinaceae SEBAGAI AKIBAT MODIFIKASI HIDROLISIS ASAM, PEMOTONGAN TITIK PERCABANGAN DAN SIKLUS PEMANASAN-PENDINGINAN [Structure Changes of Arrowroot (Maranta arundinaceae Starch as Influenced by Acid Hydrolysis, Debranching and Autoclaving-Cooling Cycle Modifications

Directory of Open Access Journals (Sweden)

Didah Nur Faridah1*

2010-12-01

Full Text Available The effects of lintnerization (2.2 N HCl, 2 hours, debranching with pullulanase (1.3 U/g and 10.4 U/g starch and/or three-auctoclaving-cooling cycles at 121oC for 15 minutes on the changes of arrowroot starch structures were studied. The structural modifications of amylose and amylopectin were measured by Gel Permiation Chromatography (GPC, and the distribution of degree of polimerization (DP was analyzed by Fluorophore-Assisted Capillary Electrophoresis (FACE. The GPC profile of native starch using Toyopearl HW-65S gel gave mainly two fractions. Fraction I (Fr. I was a high molecular weight component and Fraction II (Fr. II was a low molecular weight component. After acid modification, the carbohydrate content of Fr. II increased while that of Fr. I decreased. The amount of DP of 6 to 8 increased in all modified arrowroot starches. The GPC and FACE analyses showed that all starch modification techniques caused the structural changes of amylopectin molecules to form short chain amyloses.

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

Science.gov (United States)

Correia, P R; Beirão-da-Costa, M L

2011-03-01

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

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)

Particle size fractionation of high-amylose rice (Goami 2) flour as an oil barrier in a batter-coated fried system

Science.gov (United States)

The particle size effects of high-amylose rice (Goami 2) flour on quality attributes of frying batters were characterized in terms of physicochemical, rheological, and oil-resisting properties. High-amylose rice flours were fractionated into four fractions (70, 198, 256, and 415 µm) of which morpho...

Sweetening syrup production by enzymatic hydrolysis of starch variety yam (Dioscorea rotundata

Directory of Open Access Journals (Sweden)

Carlos Ramón Vidal Tovar

2011-04-01

Full Text Available Sweeteners syrups produced by enzymatic hydrolysis from starch of hawthorn yam (Dioscorea rotundata. The starch was extracted by a scratched, washed, sedimented and drying; the yield was quantified taking into account the amount of initial raw material and was determined the concentration of starch, amylose, amylopectin, crude fiber, ash, protein, fat and humidity in accordance with the requirements of the AOAC standards, and ICONTEC COVENIN. Enzymatic hydrolysis of starch was conducted using ∂-amylase, glucoamylase and pullulanase in starch solutions at 36 and 46 % w/w varying the order of application of glucoamylase and pullulanase were determined pH, Brix, moisture, reducing sugars (AR, total sugar (TS and the dextrose equivalent (ED in the syrups obtained. In the liquefaction were obtained with an intermediate syrups sweeteners ED 18.81% and 22.15%. Syrups low and medium conversion with an ED between 34-45% in the first saccharification and high conversion syrups with a DE between 75-79% as a final product. The above values allow the use of hawthorn yam starch syrup production for multiple uses in different food industry processes.

Occurrence of amylose-lipid complexes in teff and maize starch biphasic pastes

CSIR Research Space (South Africa)

Wokadala, OC

2012-09-01

Full Text Available The occurrence of amylose–lipid complexes was determined in maize and teff starch biphasic pastes i.e. peak viscosity pastes at short and prolonged pasting times. Maize and teff starches were pasted for 11.5 and 130 min with or without added stearic...

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

Insights into the structural and physicochemical properties of small granular starches from two hydrophyte duckweeds, Spirodela oligorrhiza and Lemna minor.

Science.gov (United States)

Chen, Lei; Yu, Changjiang; Ma, Yubin; Xu, Hua; Wang, Shumin; Wang, Yu; Liu, Xingxun; Zhou, Gongke

2016-11-29

The structure and physicochemical properties of starches from two hydrophyte duckweeds, Spirodela oligorrhiza and Lemna minor, were investigated and compared in this study. The amylose content and average size of starches were determined to be 20.85%, 4.70 μm and 27.77%, 6.17 μm for Spirodela oligorrhiza and Lemna minor, respectively. The average chain length of two duckweed starches was measured to be around DP 28. The chain length distribution was observed to be greatly different from other reported starches for the high proportion of long chains (DP ≥ 37) over 50%. Wide-angle X-ray diffraction profiles of the two starch samples displayed typical B-type diffraction pattern. The gelatinization enthalpy-changes (ΔH gel ) of two starch samples was about 10.40 J/g for two duckweed starches. The present results suggested the potential utilization of small granular starches from duckweed in functional foods and dietary supplement products. Copyright © 2016 Elsevier Ltd. All rights reserved.

Study on Hot-wire Method for Measuring the Thermal Conductivity of food Materials%银杏淀粉的分离和纯化

Institute of Scientific and Technical Information of China (English)

敖自华; 王璋; 许时婴

2001-01-01

High ly purified amylopectin and amylose from ginkgo biloba L.starch could be obtained by recrystallization. Results of gel permeation chromatography (GPC) on sepharose 2B showed that molecular weight of ginkgo amylose appeared to be smaller than that of corn amylose,whereas the amylopectin molecular weight had a wide distribution in the GPC profile. For ginkgo amylose and amylopectin,iodine affinity values were 19.19％ and 0.13％ ,blue values 0.85 and 0.12.and λ max of I2-KI blue colour 626nm and 564nm ,respectively. Amylose content of ginkgo starch was 33％.%用重结晶法可以得到纯度较高的银杏直链淀粉和支链淀粉。凝胶过滤色谱表明：银杏直链淀粉的分子量比玉米直链淀粉的小，而支链淀粉的分子量则具有较宽的分布。银杏直、支链淀粉的碘亲和力分别为19.19％和0.1 3％，蓝值分别是0.85和0.12，λmax为626nm和564nm；银杏淀粉中直链淀粉含量为33％。

In vitro starch hydrolysis and estimated glycemic index of tef porridge and injera.

Science.gov (United States)

Shumoy, Habtu; Raes, Katleen

2017-08-15

The aim of this study was to investigate the in vitro starch digestibility of injera and porridge from seven tef varieties and to estimate their glycemic index. The total starch, free glucose, apparent amylose, resistant, slowly digestible and rapidly digestible starches of the varieties ranged between 66 and 76, 1.8 and 2.4g/100g flour dry matter (DM), 29 and 31%, 17 and 68, 19 and 53, 12 and 30g/100g starch DM, respectively. After processing into injera and porridge, the rapidly digestible starch content increased by 60-85% and 3-69%, respectively. The estimated glycemic index of porridge and injera of the varieties ranged 79-99 and 94-137 when estimated based on model of Goni et al. (1997) whereas from 69 to 100 and 94 to 161, respectively based on Granfeldtet al. (1992). Tef porridge and injera samples studied here can be classified as medium- high GI foods, not to be considered as a proper food ingredient for diabetic people and patients in weight gain control. Copyright © 2017 Elsevier Ltd. All rights reserved.

Physicochemical and functional properties of gamma irradiated buckwheat and potato starch

Science.gov (United States)

Verma, Ruchi; Jan, Shumaila; Rani, Savita; Jan, Kulsum; Swer, Tanya L.; Prakash, Kumar S.; Dar, M. Z.; Bashir, Khalid

2018-03-01

Starches isolated from buckwheat and potato were subject to different doses of irradiation at 0, 5, 10, 15 and 20 kGy. Native and irradiated starch samples were evaluated for their physicochemical and functional properties to assess the effect of gamma irradiation. Apparent amylose content decreased significantly from 26.84% to 22.12% and 27.01 to 16.11% for buckwheat and potato starch respectively as the dose increased. A significant decrease was observed in pH, swelling power and syneresis as the dose increased for both buckwheat and potato starch. pH decreased from 5.20 to 3.81 and 5.81 to 3.95 for buckwheat and potato starch, respectively. Carboxyl content, freeze thaw stability, water and oil absorption capacity and transmittance showed increasing trend with increasing irradiation dose. Carboxyl content increased from 0% to 0.23% and 0-0.22% for buckwheat and potato starch, respectively.

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.

Functional and structural characterization of plastidic starch phosphorylase during barley endosperm development

DEFF Research Database (Denmark)

Cuesta-Seijo, Jose A.; Ruzanski, Christian; Krucewicz, Katarzyna

2017-01-01

The production of starch is essential for human nutrition and represents a major metabolic flux in the biosphere. The biosynthesis of starch in storage organs like barley endosperm operates via two main pathways using different substrates: starch synthases use ADP-glucose to produce amylose......,4-glucans using HvPho1 from G1P as the sole substrate. The structural properties of HvPho1 provide insights into the low affinity of HvPho1 for large polysaccharides like starch or amylopectin. Our results suggest that HvPho1 may play a role during the initiation of starch biosynthesis in barley....... and amylopectin, the two major components of starch, whereas starch phosphorylase (Pho1) uses glucose-1-phosphate (G1P), a precursor for ADP-glucose production, to produce α-1,4 glucans. The significance of the Pho1 pathway in starch biosynthesis has remained unclear. To elucidate the importance of barley Pho1...

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.

FORMULASI TEPUNG PENYALUT BERBASIS TEPUNG JAGUNG DAN PENENTUAN UMUR SIMPANNYA DENGAN PENDEKATAN KADAR AIR KRITIS [Formulation of Corn Flour-Based Batter and Prediction of Its Shelf Life using Critical Moisture Approach

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Sugiyono1*

2010-12-01

Full Text Available The objectives of this study were to obtain the best formula for corn flour-based batter and to predict its shelf life using critical moisture approach. According to a hedonic test, the best batter formula was composed of 60% corn flour, 12.5% rice flour, 12.5% tapioca starch, and 15% glutinous rice flour. Addition of glutinous rice flour in the formula changed the proportion of amylose and amylopectin in the batter. As a result, the retrogradation of the batter decreased and the texture of its fried product was preferred. A critical moisture approach was used to predict the shelf life of the batter. The critical moisture content of the batter was 0.16 g H2O/g solid.The isotherm sorption phenomenon of the batter was best described using Hasley model. The shelf life of the product was 7 months when packaged in polypropylene (0,07 g/m2day.mmHg at 85% RH.

Effect of a small amount of sodium carbonate on konjac glucomannan-induced changes in thermal behavior of wheat starch.

Science.gov (United States)

Zhou, Yun; Winkworth-Smith, Charles G; Wang, Yu; Liang, Jianfen; Foster, Tim J; Cheng, Yongqiang

2014-12-19

The effects of konjac glucomannan (KGM) on thermal behavior of wheat starch have been studied in the presence of low concentrations of Na2CO3 (0.1-0.2 wt% of starch). Confocal laser scanning microscopy (CLSM) allows the visualization of the starch gelatinization process and granule remnants in starch pastes. Heating the starch dispersion in KGM-Na2CO3 solution significantly delays granule swelling and inhibits amylose leaching, whereas Na2CO3 alone, at the same concentration, has little effect. Na2CO3 assists KGM in producing the extremely high viscosity of starch paste, attributing to a less remarkable breakdown of viscosity in subsequent heating, and protecting starch granules against crystallite melting. The distinct partially networked film around the surface of starch granules is evident in the CLSM images. We propose that Na2CO3 could trigger the formation of complexes between KGM and starch polymers, which exerts a protective effect on granular structure and modifying gelatinization characteristics of the mixtures. Copyright © 2014 Elsevier Ltd. All rights reserved.

Phosphate fertilization changes the characteristics of 'Maçã' banana starch.

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Mesquita, Camila de Barros; Garcia, Émerson Loli; Bolfarini, Ana Carolina Batista; Leonel, Sarita; Franco, Célia Maria L; Leonel, Magali

2018-06-01

The unripe banana has been studied as a potential source of starch for use in various applications. Considering the importance of phosphorus in the biosynthesis of the starch and also the interference of this mineral in starch properties, in this study it was evaluated the effect of rates of phosphate fertilizer applied in the cultivation of 'Maçã' banana on the characteristics of the starch. Starches extracted from fruits from different treatments were analyzed for morphological characteristics, X-ray diffraction pattern, relative crystallinity, granule size, amylose, resistant starch and phosphorus levels, as well as, for pasting and thermal properties. Results showed that the phosphate fertilization has interference on the characteristics of the banana starch led to increase of phosphorus content and size of the granules, reduction of crystallinity and resistant starch content, decrease of viscosity peak, breakdown, final viscosity, setback, transitions temperatures and enthalpy. These changes caused by phosphate fertilizer conditions can be increase the applications of the 'Maçã' banana starch. Copyright © 2018. Published by Elsevier B.V.

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.

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...

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

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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

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

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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

Comparison of starch granule development and physicochemical properties of starches in wheat pericarp and endosperm.

Science.gov (United States)

Yu, Xurun; Zhou, Liang; Zhang, Jing; Yu, Heng; Xiong, Fei; Wang, Zhong

2015-01-01

The objectives of this study were: (i) to characterize structural development of starch granule in pericarp and endosperm during wheat caryopsis growth; (ii) to compare physicochemical properties of starches in pericarp and endosperm; (iii) to further discover the relationships between pericarp starches and endosperm starches. Wheat pericarp and endosperm at different development stages were observed by light microscopy and scanning electron microscopy, respectively. Structural properties of starches were determined using X-ray power diffraction and (13) C solid nuclear magnetic resonance. Pericarp starch granules (PSG) accumulated in amyloplasts and chloroplasts, and showed a typical accumulation peak at 5 days after fertilization (DAF), and then gradually decomposed during 5-22 DAF. PSG in the abdominal region showed a higher rate of decomposition compared to the dorsal region of pericarp. Endosperm starch granules (ESG) accumulated in amyloplasts, and occurred in endosperm cells at 5 DAF, then rapidly enriched the endosperm cells until 22 DAF. Compared with ESG, PSG were compound granules of irregular shape and small size distribution. The results also suggested lower amylose content and V-type single-helix content and higher proportions of double helices for PSG compared to ESG. Based on the structural development of PSG and ESG, we speculated that the saccharides resulting from decomposition of PSG, on one hand, enabled the pericarp to survive before maturity of wheat caryopsis and, on the other hand, provided extra nutrition for the growth of ESG. © 2014 Society of Chemical Industry.

Modification of wheat starch with succinic acid/acetic anhydride and azelaic acid/acetic anhydride mixtures I. Thermophysical and pasting properties.

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Subarić, Drago; Ačkar, Durđica; Babić, Jurislav; Sakač, Nikola; Jozinović, Antun

2014-10-01

The aim of this research was to investigate the influence of modification with succinic acid/acetic anhydride and azelaic acid/acetic anhydride mixtures on thermophysical and pasting properties of wheat starch. Starch was isolated from two wheat varieties and modified with mixtures of succinic acid and acetic anhydride, and azelaic acid and acetic anhydride in 4, 6 and 8 % (w/w). Thermophysical, pasting properties, swelling power, solubility and amylose content of modified starches were determined. The results showed that modifications with mixtures of afore mentioned dicarboxylic acids with acetic anhydride decreased gelatinisation and pasting temperatures. Gelatinisation enthalpy of Golubica starch increased, while of Srpanjka starch decreased by modifications. Retrogradation after 7 and 14 day-storage at 4 °C decreased after modifications of both starches. Maximum, hot and cold paste viscosity of both starches increased, while stability during shearing at high temperatures decreased. % setback of starches modified with azelaic acid/acetic anhydride mixture decreased. Swelling power and solubility of both starches increased by both modifications.

A resistant-starch enriched yogurt: fermentability, sensory characteristics, and a pilot study in children

Science.gov (United States)

Aryana, Kayanush; Greenway, Frank; Dhurandhar, Nikhil; Tulley, Richard; Finley, John; Keenan, Michael; Martin, Roy; Pelkman, Christine; Olson, Douglas; Zheng, Jolene

2015-01-01

The rising prevalence of obesity and the vulnerability of the pediatric age group have highlighted the critical need for a careful consideration of effective, safe, remedial and preventive dietary interventions.  Amylose starch (RS2) from high-amylose maize (HAM) ferments in the gut and affects body weight.   One hundred and ten children, of 7-8 (n=91) or 13-14 (n=19) years of age scored the sensory qualities of a yogurt supplemented with either HAM-RS2 or an amylopectin starch.  The amylopectin starch yogurt was preferred to the HAM-RS2-enriched yogurt by 7-8 year old panelists ( Pyogurt than for HAM-RS2-enriched yogurt ( Pyogurt in 74% of subjects.  Four children consumed a HAM-RS2-enriched yogurt for four weeks to test its fermentability in a clinical trial.  Three adolescents, but not the single pre-pubertal child, had reduced stool pH ( P=0.1) and increased stool short-chain fatty acids (SCFAs) ( Pfermentation and isobutyrate ( P=0.01) from protein fermentation post-treatment suggesting a favorable change to the gut microbiota.  HAM-RS2 was not modified by pasteurization of the yogurt, and may be a palatable way to increase fiber intake and stimulate colonic fermentation in adolescents.  Future studies are planned to determine the concentration of HAM-RS2 that offers the optimal safe and effective strategy to prevent excessive fat gain in children. PMID:26925221

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

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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.

A Review on the Role of Vibrational Spectroscopy as An Analytical Method to Measure Starch Biochemical and Biophysical Properties in Cereals and Starchy Foods

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D. Cozzolino

2014-12-01

Full Text Available Starch is the major component of cereal grains and starchy foods, and changes in its biophysical and biochemical properties (e.g., amylose, amylopectin, pasting, gelatinization, viscosity will have a direct effect on its end use properties (e.g., bread, malt, polymers. The use of rapid and non-destructive methods to study and monitor starch properties, such as gelatinization, retrogradation, water absorption in cereals and starchy foods, is of great interest in order to improve and assess their quality. In recent years, near infrared reflectance (NIR and mid infrared (MIR spectroscopy have been explored to predict several quality parameters, such as those generated by instrumental methods commonly used in routine analysis like the rapid visco analyser (RVA or viscometers. In this review, applications of both NIR and MIR spectroscopy to measure and monitor starch biochemical (amylose, amylopectin, starch and biophysical properties (e.g., pasting properties will be presented and discussed.

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)

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)

Rheological, pasting, thermal and retrogradation properties of octenyl succinic anhydride modified potato starch

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Chuin WON

Full Text Available Abstract The objective of the present study was to investigate the rheological, pasting, and thermal properties of octenyl succinic anhydrate (OSA-modified potato starch. Potato starch was modified using different concentrations of OSA (0, 1, 3, and 5%, v/v. The degree of substitution (DS for the OSA-modified starch ranged from 0.0012 to 0.0055. The amylose leaching values of native and OSA-modified potato starch with different DS levels were in the range of 47.09-87.32%. The gel strength values of the OSA-modified starch were lower than those of native potato starch. Rapid Visco Analyzer data showed that peak, hot pasting, final and setback viscosities of the native starch decreased after OSA modification. Dynamic shear rheological tests, conducted at 4 °C, indicated that OSA-modified potato starch had weak gel-like behavior with the storage moduli (G' higher than the loss moduli (G” over most of the frequency ranges (0.63-63.8 rad·s-1.

Characterization of tropical starches modified with potassium permanganate and lactic acid

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Fabiano Franco Takizawa

2004-11-01

Full Text Available In the present work some tropical starches were modified by an oxidative chemical treatment with potassium permanganate and lactic acid. The native and modified samples were evaluated by mid-infrared spectroscopy, differential dyeing, pH, expansion power, solubility and swelling power, clarity of the pastes, susceptibility to syneresis, carboxyl content and reducing power. All modified samples presented dark blue color, higher expansion power (except corn starch, carboxyl content and reducing power. The solubility of the modified starch granules was very high at 90ºC. At this temperature, it was not possible to measure their swelling power. The viscographic analysis showed decrease in peak viscosity and higher degree of cooking instability. The principal component analysis of the mid-infrared spectra allowed separation between native and modified samples due to the presence of carboxyl groups. The expansion was inversely related with amylose content of the starches.No presente trabalho alguns amidos tropicais foram modificados por tratamento oxidativo com permanganato de potássio e ácido lático. Amidos nativos e modificados foram avaliadas por espectroscopia na região do infravermelho médio, coloração diferencial, pH, propriedade de expansão, poder de inchamento e solubilidade, claridade das pastas, susceptibilidade a sinérese, teor carboxilas e poder redutor. Todas as amostras modificadas adquiriram intensa coloração azul quando suspensas em azul de metileno, maiores valores de expansão (exceto o amido de milho, teor de carboxilas e poder redutor. A solubilidade dos grânulos dos amidos modificados foi muito alta a temperatura de 90°C, não tendo sido possível medir o poder de inchamento. A análise viscográfica mostrou um decréscimo no pico de viscosidade e alta instabilidade ao cozimento. A análise dos componentes principais dos espectros de infravermelho médio permitiu a separação entre as amostras nativas e modificadas

Encapsulation and delivery of food ingredients using starch based systems.

Science.gov (United States)

Zhu, Fan

2017-08-15

Functional ingredients can be encapsulated by various wall materials for controlled release in food and digestion systems. Starch, as one of the most abundant natural carbohydrate polymers, is non-allergenic, GRAS, and cheap. There has been increasing interest of using starch in native and modified forms to encapsulate food ingredients such as flavours, lipids, polyphenols, carotenoids, vitamins, enzymes, and probiotics. Starches from various botanical sources in granular or amorphous forms are modified by chemical, physical, and/or enzymatic means to obtain the desired properties for targeted encapsulation. Other wall materials are also employed in combination with starch to facilitate some types of encapsulation. Various methods of crafting the starch-based encapsulation such as electrospinning, spray drying, antisolvent, amylose inclusion complexation, and nano-emulsification are introduced in this mini-review. The physicochemical and structural properties of the particles are described. The encapsulation systems can positively influence the controlled release of food ingredients in food and nutritional applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of Acacia Gum, NaCl, and Sucrose on Physical Properties of Lotus Stem Starch

Science.gov (United States)

Gill, Balmeet Singh

2014-01-01

Consumer preferences in east Asian part of the world pave the way for consumption of lotus stem starch (LSS) in preparations such as breakfast meals, fast foods, and traditional confectioneries. The present study envisaged the investigation and optimization of additives, that is, acacia gum, sodium chloride (NaCl), and sucrose, on water absorption (WA), water absorption index (WAI), and water solubility index (WSI) of LSS employing response surface methodology (RSM). Acacia gum resulted in increased water uptake and swelling of starch; however, NaCl reduced the swelling power of starch by making water unavailable to starch and also due to starch-ion electrostatic interaction. Sucrose restricted the water absorption by binding free water and decreased amylose leaching by building bridges with starch chains and thus forming rigid structure. PMID:26904639

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.).

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.

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.