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Showing papers in "Cereal Chemistry in 1997"


Journal ArticleDOI
TL;DR: In this paper, the authors determined the fundamental basis of variation in gelatinization, pasting, and gelation of prime starch derived from seven different wheat cultivars: Kanto 107, which is a partial waxy mutant line, and six near-isogenic lines (NILs) differing in hardness.
Abstract: The starch of wheat (Triticum aestivum L.) flour affects food product quality due to the temperature-dependent interactions of starch with water during gelatinization, pasting, and gelation. The objective of this study was to determine the fundamental basis of variation in gelatinization, pasting, and gelation of prime starch derived from seven different wheat cultivars: Kanto 107, which is a partial waxy mutant line, and six near-isogenic lines (NILs) differing in hardness. Complete pasting curves with extended 16-min hold at 93°C were obtained using the Rapid Visco Analyser (RVA). Apparent amylose content ranged from 17.5 to 23.5%; total amylose content ranged from 22.8 to 28.2%. Starches exhibited significant variation in onset of gelatinization. However, none of the parameters measured consistently correlated with onset or other RVA curve parameters that preceded peak paste viscosity. Peak paste viscosity varied from 190 to 323 RVA units (RVU). Higher peak, greater breakdown, lower final visc...

311 citations


Journal ArticleDOI
TL;DR: In this paper, a small amplitude oscillatory rheometry was used to investigate the influence of granular structure on the pasting behavior of starch, using small amplitude amplitude oscillation.
Abstract: Japonica (Tainung 67 [TNu67]) and waxy (Taichung 70 [TCW70]) rice, normal and waxy corn, and cross-linked waxy rice and corn starches were used in an investigation of the influence of the granular structure on the pasting behavior of starch, using small amplitude oscillatory rheometry. Both normal corn and normal rice (TNu67) starches had the highest storage moduli (G′), followed by their cross-linked versions; native waxy corn and rice starches had the lowest. Native waxy starches showed paste characteristics (G′ 0.2) at concentrations of up to 35%. However, cross-linked waxy starches exhibited gel behavior at 10% concentration (cross-linked TCW70) or higher (cross-linked waxy corn starch). The degrees of swelling power were in the order: TCW70 > native waxy corn > TNu67 ≅ cross-linked TCW70 ≅ normal corn ≅ cross-linked waxy corn starches. Solubilities were in the order: normal corn > TNu67 > native waxy > cross-linked waxy starches. The addition of 2% purified amylose from ind...

260 citations


Journal ArticleDOI
TL;DR: For the first time, alkaline hydrogen peroxide (AHP) extraction conditions were used to isolate hemicellulose (arabinoxylan) from destarched corn fiber.
Abstract: For the first time, alkaline hydrogen peroxide (AHP) extraction conditions were used to isolate hemicellulose (arabinoxylan) from destarched corn fiber. Yields of the water-soluble hemicellulose B ranged from 35% (24 hr extraction at 25°C) to 42% (2 hr extraction at 60°C). The hemicellulose B resulting from the 2 hr extraction (pH 11.5) was off-white in color, and a very low proportion (1.7%) of water-insoluble hemicellulose A was extracted. AHP treatment caused delignification and facilitated the alkaline extraction of hemicellulose from the lignocellulosic fiber matrix. In the absence of H2O2, yields were reduced by more than one-third when using otherwise identical extraction conditions of time, temperature and pH. In the standard protocol, corn fiber, NaOH solution, and H2O2 were mixed in a 1:25:0.25 (w/v/w) ratio. Extractions were conducted at pH 11.5 at 25°C or 60°C. The pH was adjusted to 11.5 by addition of NaOH at ambient and elevated temperatures. The optimum hemicellulose yield (51.3%;...

232 citations


Journal ArticleDOI
TL;DR: In this paper, the authors examined turbidometric analysis and light microscopy of 2% pastes prepared from unmodified commercial starches by cooking at 98-100°C under low shear, then held at 4°C for 56 days, and found that retrogradation rates followed the order of wheat, common corn > rice, tapioca, potato ≫ waxy maize.
Abstract: Retrogradation in 2% pastes prepared from unmodified commercial starches by cooking at 98–100°C under low shear, then held at 4°C for 56 days, was examined by turbidometric analysis and light microscopy. Turbidometric analysis revealed that retrogradation rates followed the order of wheat, common corn > rice, tapioca, potato ≫ waxy maize. Microstructures of stored pastes were examined both before and after centrifugation. Granule remnant morphologies and fresh and stored paste microstructures were unique to each starch examined. Fresh pastes from amylose-containing starches were dominated by networked amylose that condensed into higher density aggregates upon storage. Unique phenomena seen in some stored pastes included interactions of granular remnants with aggregated amylose, composite networks of co-associated amylopectin and amylose, and slight birefringence regained by granule remnants. Microstructural changes in stored pastes could be related to changes in turbidity and to the results of ot...

196 citations


Journal ArticleDOI
TL;DR: In this article, a mutant sorghum starch with numerous, large surface pores was treated with a methanolic solution of merbromin and sectioned to reveal channels connecting an internal cavity to the external surface in most granules.
Abstract: Evidence is presented that corn (maize) and sorghum starch granules have channels that connect a central cavity to the external environment. A mutant sorghum starch with numerous, large surface pores was treated with a methanolic solution of merbromin and sectioned. Light, fluorescence, and compositional backscattering electron microscopy revealed channels connecting an internal cavity to the external surface in most granules. Cavities and channels could also be seen in whole corn and sorghum starch granules treated with merbromin in methanol and viewed by fluorescence microscopy. Treatment of sorghum starch granules with an aqueous solution of merbromin revealed that the molecule penetrated the granule matrix under even slightly swelling conditions. Light microscopy showed cavities in unstained, whole, dry corn and sorghum starch granules mounted in immersion oil.

195 citations


Journal ArticleDOI
TL;DR: In this article, a method for preparation of zein films involving plasticization of vein with oleic acid to form an intermediate moldable resins was presented, where the resin was stretched over rigid frames to form thin membranes that were set in flexible films.
Abstract: A new method for preparation of zein films involving plasticization of zein with oleic acid to form an intermediate moldable resin was presented. The resin was stretched over rigid frames to form thin membranes that were set in flexible films. The objective of the study was to investigate the effect of film preparation method on film properties. Tensile properties, microstructure, and thermal behavior of zein films plasticized with oleic acid were investigated for films prepared by conventional casting from ethanol solutions and by stretching of plasticized resins. Cast films were stiff and brittle, whereas resin films showed more flexibility and toughness. Differential scanning calorimetry thermograms of cast films indicated phase separations were generated when heated that were not observed for resin films. Microstructure images showed a higher degree of structure development and orientation in resin than in cast films. Glass-transition temperatures of resin films were measured at -94 and 104.4...

194 citations


Journal ArticleDOI
TL;DR: In this paper, the molecular weight of β-glucan was determined using high-performance size-exclusion chromatography for oat bran and oat porridge.
Abstract: The extractability and molecular weight of β-glucan in oat bran, oat bran muffins, and oat porridge and the changes taking place during processing and storage were studied. The β-glucan was extracted using hot water and a thermostable α-amylase and by an in vitro system that simulated human digestion. Molecular weight (MW) of the extracted β-glucan was determined using high-performance size-exclusion chromatography. Hot-water treatment extracted 50–70% of total β-glucan in oat bran samples and rolled oats. The chromatographic peak MW of extracted β-glucan was in the 1.4–1.8 × 106 range. Using the in vitro digestion system, 12–33% of total β-glucan in bran and rolled oats was solubilized, and peak MW was in the same range as β-glucan extracted by hot-water treatment. In muffins, 30–85% of total β-glucan was solubilized by in vitro digestion, with a major difference in extractability among muffins from different recipes. Peak MW of extracted β-glucan was lower in all muffins when compared to origin...

183 citations


Journal ArticleDOI
TL;DR: The viscoelastic properties and molecular structure of the starch isolated from waxy hexaploid wheat (WHW) (Triticum aestivum L.) were examined in this paper.
Abstract: The viscoelastic properties and molecular structure of the starch isolated from waxy (amylose-free) hexaploid wheat (WHW) (Triticum aestivum L.) were examined. WHW starch generally had lower gelatinization onset temperature, peak viscosity, and setback than the starch isolated from normal hexaploid wheat (NHW). Differential scanning calorimetry (DSC) showed that WHW starch had higher transition temperatures (To, Tp, and Tc) and enthalpy (ΔH) than NHW starch. However, when compared on the basis of amylopectin (AP) content, ΔH of WHW starch was almost statistically identical to that of its parental varieties. Typical A-type X-ray diffraction patterns were observed for the starches of WHW and its parental varieties. Somewhat higher crystallinity was indicated for WHW starch. WHW starch was also characterized by having greater retrogradation resistance. The high-performance size-exclusion chromatography (HPSEC) of amylopectin showed that each amylopectin yielded two fractions after debranching. Altho...

174 citations


Journal ArticleDOI
TL;DR: In this article, β-glucan, a soluble, viscous polymer found in oat and barley endosperm cell wall, was incorporated into pasta test meals, which resulted in a lower glycemic response as measured by average total area and maximum increment of the blood glucose curves.
Abstract: High-fiber, high-carbohydrate diets, including foods with low glycemic index, have been associated with prevention and treatment of diseases such as coronary heart disease and diabetes. β-glucan, a soluble, viscous polymer found in oat and barley endosperm cell wall, was incorporated into pasta test meals. Five fasted adult subjects were fed test meals of a barley and durum wheat blend pasta containing 100 g of available carbohydrate, 30 g of total dietary fiber (TDF) and 12 g of β-glucan, or an all durum wheat pasta containing the same amount of available carbohydrate, 5 g of TDF, and negligible β-glucan. The β-glucan and durum wheat pasta resulted in a lower glycemic response as measured by average total area and maximum increment of the blood glucose curves. Lower insulin response to the β-glucan and durum wheat pasta was also indicated by lower average area and increment characteristics of the insulin curves. Barley β-glucans may be an economical and palatable ingredient for processed food pr...

157 citations


Journal ArticleDOI
TL;DR: In this article, the effect of nonwaxy and waxy rice starch-lipid complexes on the rate of in vitro digestibility was determined, and the largest decrease in digestibility (33%) was achieved with Polyaldo 10-1-2 (100% C18:0 with decaglyceryl monostearate modification).
Abstract: Effects of nonwaxy (21% amylose, 79% amylopectin) and waxy (100% amylopectin) rice starch-lipid complexes on the rate of in vitro digestibility were determined. Long-chain (≥C:18) saturated emulsifiers reduced digestibility more than short-chain (

157 citations


Journal ArticleDOI
TL;DR: Glycerol-plasticized soy protein films were cast from alkaline aqueous film-forming solutions of laboratory-prepared 7S, 11S, and soy isolate (LSI) fractions and from commercial soy isolate.
Abstract: Glycerol-plasticized soy protein films were cast from alkaline aqueous film-forming solutions of laboratory-prepared 7S, 11S, and soy isolate (LSI) fractions and from commercial soy isolate (CSI). Tensile strength (TS), elongation at break (E), water vapor permeability (WVP), total soluble matter (TSM), protein solubility (PS), and Hunter L, a, and b color values of these films were determined. The 11S films had greater TS than 7S films (P 0.05). The 7S films had higher TSM and PS values than 11S films (P < 0.05). CSI films were significantly darker (lower L value) and more yellow (greater positive b value) than LSI films (P < 0.05).

Journal ArticleDOI
TL;DR: In this paper, the tensile properties, water absorption, and microstructure of zein sheets plasticized with palmitic and stearic acids were investigated based on value-added considerations and on the unique thermoplastic and hydrophobic properties of Zein.
Abstract: Interest in biodegradable materials for packaging and agricultural uses has grown in recent years. Plant proteins have been proposed as inexpensive, renewable, and abundant feedstock. Corn zein was investigated based on value-added considerations and on the unique thermoplastic and hydrophobic properties of zein. Films prepared from zein are known to be tough and resistant, but also hard and brittle, thus requiring the addition of plasticizers to improve flexibility. The objectives of this research were to study the tensile properties, water absorption, and microstructure of zein sheets plasticized with palmitic and stearic acids. Both palmitic and stearic acids showed similar effects as plasticizers of zein. Tensile strength of zein sheets increased with the addition of low levels of plasticizers. However, beyond a critical point, tensile strength decreased with further addition of fatty acids. Water absorption decreased continuously with increasing fatty acid content. Kinetic parameters indicat...

Journal ArticleDOI
TL;DR: The content and molecular weight (MW) of β-glucan in extracts from a selection of oat and barley cultivars were compared using flow-injection analysis and high-performance size-exclusion chromatography as discussed by the authors.
Abstract: The content and molecular weight (MW) of β-glucan in extracts from a selection of oat and barley cultivars were compared using flow-injection analysis and high-performance size-exclusion chromatography. From 60 to 75% of the β-glucan was extracted from oat and waxy barley by hot water (90°C) containing heat-stable α-amylase, whereas just 50–55% was extracted from nonwaxy barley. Consecutive extractions with hot water and dimethylsulfoxide (DMSO) extracted 65% (nonwaxy barley) or 75–80% (oat and waxy barley) of the total β-glucan. An extraction with sodium hydroxide and sodium borohydride (NaOH/NaBH4) increased the percentage of β-glucan extracted to 86–100% but decreased the MW. The MW of β-glucan in the oat cultivars selected was significantly higher than those in the barley cultivars. The β-glucan extracted from the nonwaxy barley cultivars showed significantly higher peak MW than that from the waxy barley cultivars.

Journal ArticleDOI
TL;DR: In this paper, Zhao et al. used hot-stage polarized light microscopy and differential scanning calorimetry of isolated starch revealed increasing gelatinization temperatures with increasing lime concentrations, suggesting that the high pH of the system causes starch hydroxyl groups to ionize, thereby creating binding sites for Ca++/CaOH+ and producing Ca-starch crosslinks.
Abstract: Analysis of swelling power, water retention capacity, and degree of gelatinization of corn flour cooked in water with and without lime indicated, over a concentration range of 0–1% (w/v), that at low concentrations, lime increases swelling and digestibility of starch granules. Measurement of starch solubility revealed an increase in the amount of starch dissolved by lime cooking. Swelling, retention, and gelatinization exhibited maxima at or near 0.2% (w/v) lime, and then decreased as lime concentration increased. Hot-stage polarized light microscopy and differential scanning calorimetry of isolated starch revealed increasing gelatinization temperatures with increasing lime concentrations. It is hypothesized that the high pH of the system causes starch hydroxyl groups to ionize, thereby creating binding sites for Ca++/CaOH+ and producing Ca-starch crosslinks. It is also suggested that, at low lime levels (<0.4%, w/v), granule crystalline regions are disrupted and the granule matrix is stretched b...

Journal ArticleDOI
TL;DR: In this article, the authors present quantitative data and odor activity values (ratio of concentration to odor threshold) of key odorants in bread (wheat and rye), toasted bread, puff pastries made with different fats, fragrant and nonfragrant rices, sweet corn, popcorn, and tortillas.
Abstract: The review is focused on studies presenting quantitative data and odor activity values (ratio of concentration to odor threshold) of key odorants in bread (wheat and rye), toasted bread, puff pastries made with different fats, fragrant and nonfragrant rices, sweet corn, popcorn, and tortillas. The influence of raw materials, processing parameters, and storage conditions on the concentrations of key odorants and some data on flavor precursors and formation pathways of these compounds are discussed.

Journal ArticleDOI
TL;DR: In this paper, simple phenolic acid levels were determined on pooled millstreams of five different classes of Canadian wheat milled to ~75, 80, and 85% extraction.
Abstract: Simple phenolic acid levels were determined on pooled millstreams of five different classes of Canadian wheat milled to ~75, 80, and 85% extraction. Pooled flours and whole grain were analyzed by reversed-phase high-performance liquid chromatography (RP-HPLC) to establish endogenous levels of insoluble bound, soluble esterified, and free phenolic acids. Only ferulic acid was detected in the insoluble bound category, which accounted for >80% of the total phenolic acids present in every flour. The soluble esterified phenolic acids accounted for up to 17% of the overall total phenolic acid content within a flour. The major constituents were sinapic, ferulic, and vanillic acids, with minor amounts of coumaric, caffeic, and syringic acids. Free phenolic acids accounted for a maximum of 6% of the total phenolic content of any prepared flour. Ferulic acid was the major free phenolic acid, while sinapic acid was not detected in any flour. Significant correlations (r = 0.64–0.97, P < 0.05) were observed b...

Journal ArticleDOI
TL;DR: Despite a breakdown of disulfide bonds of the residue protein during sodium hydroxide solubilization, the Mr of the majority of the fully dissociated polypeptides of this fraction ranged from 45 to 150 kDa, which was due mainly to its strong aggregation and extensive disulfides bond cross-linking.
Abstract: Proteins from the defatted brans of representative rice cultivars were fractionated into albumins, globulins, prolamins, and acid-soluble glutelins, accounting for 34, 15, 6, and 11% of the total bran proteins, respectively. The remaining insoluble residue protein, after treatment with 0.1M sodium hydroxide, resulted in the solubilization of 95% of the residue protein, representing 32% of the total bran protein. The relative molecular mass (Mr) values determined by size-exclusion HPLC were 10–100 kDa, 10–150 kDa, 33–150 kDa, and 25–100 kDa for the fully dissociated polypeptides of albumins, globulins, prolamins, and acid-soluble glutelins, respectively. Despite a breakdown of disulfide bonds of the residue protein during sodium hydroxide solubilization, the Mr of the majority of the fully dissociated polypeptides of this fraction ranged from 45 to 150 kDa. Insolubility of residue protein was due mainly to its strong aggregation and extensive disulfide bond cross-linking. Efficient methods may be ...

Journal ArticleDOI
TL;DR: In this article, the authors examined the relationship between protein content and noodle firmness in 25 Australian wheat cultivars for their relationship to alkaline noodle quality and found that high protein content was associated with softest noodles and with cultivars containing a null allele for granule-bound starch synthase on chromosome 4A.
Abstract: Flour properties of 25 Australian wheat cultivars were examined for their relationship to alkaline noodle quality. Rapid Visco Analyzer (RVA) analyses of flours showed that RVA breakdown and final viscosity determined in both water and dilute sodium carbonate were significantly related to the alkaline noodle firmness, elasticity, and surface smoothness. Flour swelling volume (FSV) of flours was negatively correlated with alkaline noodle firmness and elasticity, and positively correlated with surface smoothness of cooked noodles. Use of a dilute sodium carbonate solution led to overall increases in both paste viscosity and FSV. High FSV and low RVA final viscosity values were associated with both the softest noodles and with cultivars containing a null allele for granule-bound starch synthase on chromosome 4A. Flour protein content and SDS sedimentation volumes were significantly related to noodle texture. The relationship between protein content and noodle firmness was dependent on the Null4A sta...

Patent
TL;DR: Starch-based microcellular foams composed of a solid matrix with a network of small open cells or pores are described in this article, which are particularly useful for encapsulation and later release of a substance.
Abstract: Starch-based microcellular foams composed of a solid matrix with a network of small open cells or pores are described. The foams have high pore volume, low density, and high surface area, and are prepared using a process wherein an aqueous gel prepared from gelatinized starch is treated to exchange the water in the gel with air while maintaining the integrity of the network of open cells or pores. The starch-based microcellular foams are particularly useful for encapsulation and later release of a substance.

Journal ArticleDOI
TL;DR: In this article, ten durum wheat cultivars harvested in Manitoba in 1995, which were downgraded primarily because of fusarium-damaged (FD) kernels, were subjected to mycological tests and evaluated for semolina milling and pasta-making quality.
Abstract: Ten durum wheat cultivars harvested in Manitoba in 1995, which were downgraded primarily because of fusarium-damaged (FD) kernels, were subjected to mycological tests and evaluated for semolina milling and pasta-making quality. Fusarium graminearum was the primary fungus infecting kernels. The ratio of FD to deoxynivlaenol (DON) level varied slightly among cultivars but was generally near unity. Retention of DON in semolina was about 50%. FD had a negative impact on kernel weight and test weight, resulting in lower semolina yield. Semolina ash content and bran specks were not affected by FD, but semolina became duller and redder. FD had no effect on protein content, but gluten strength was weaker probably due to a lower proportion of glutenins as shown by reversed-phase high-performance liquid chromatographic analysis of sequentially extracted gluten proteins. The influence of FD on gluten strength was not sufficient to alter pasta texture. FD had a strong adverse effect on pasta color. Even for ...

Journal ArticleDOI
TL;DR: In this paper, the authors compared the rheological properties of developed and undeveloped wheat flours using a farinograph and found that the developed flours require less resistance for deformation than the undevelopeds.
Abstract: Undeveloped wheat dough is essentially wheat flour that has become fully hydrated without being deformed. The rheological properties of this material were compared to dough (developed dough) made using the standard method involving a farinograph. Flow behavior of undeveloped and developed dough samples made from hard and soft wheat flours were tested using creep tests, frequency sweep oscillatory tests, and temperature sweep oscillatory tests. All experiments showed that the undeveloped dough requires less resistance for deformation than developed dough. The differences are due to the energy input received by the developed dough and the influence of this factor in forming the protein matrix associated with developed dough. To attain a comparable state as the dough made in the farinograph, an energy input must be applied to the undeveloped dough material. Understanding the differences between undeveloped and developed dough may lead to new products, equipment, and processes in the bakery industry.

Journal ArticleDOI
TL;DR: In this article, a variety of Rapid-Visco Analyser (RVA) operating conditions have been tested with starch, flour, and wholemeal for predicting the quality of wheats for the manufacture of Japanese white-salted noodles.
Abstract: A variety of Rapid-Visco Analyser (RVA) operating conditions have been tested with starch, flour, and wholemeal for predicting the quality of wheats for the manufacture of Japanese white-salted noodles. Using starch as the substrate, an initial temperature of 60°C has been found to be optimum, and the best heating time from this initial temperature to the peak temperature of 95°C was ≈6 min. Significant correlations were found between peak viscosity of starch pastes and noodle quality under these operating conditions. For flour and wholemeal samples, the correlations were not as high as for isolated starch. The correlations with wholemeal or flour and noodle quality could be improved by the addition of α-amylase inhibitors. Measuring RVA viscosity of flour or wholemeal in the presence of silver nitrate gave viscosities which showed highly significant correlations with noodle quality. These correlations were similar to those obtained with isolated starch. It appears that the improvement is due to ...

Journal ArticleDOI
TL;DR: In this paper, the Rapid Visco-Analyzer (RVA) viscoamylographs of the starches showed Type A pasting curves, characterized by a high pasting peak followed by high degree of shear-thinning.
Abstract: Starch was extracted from 14 sweetpotato genotypes from the Philippines. The Rapid Visco-Analyzer (RVA) viscoamylographs of the starches showed Type A pasting curves, characterized by a high pasting peak followed by a high degree of shear-thinning. The major difference among genotypes was in the sharpness of the peak, with some showing a very sharp peak while others showed a broad peak. This difference was related to time from onset of pasting to peak viscosity, and to stability ratio (holding viscosity/peak viscosity), which were also highly correlated (r = 0.84, P < 0.01) to each other. Stability ratio was also correlated to noodle firmness (r = 0.95, P < 0.01), rehydration (cooked weight) (r = -0.89, P < 0.01), and swelling volume of the starch (r = -0.62, P < 0.05). The amylose content was correlated significantly only to peak viscosity (r = -0.84, P < 0.01). Significant differences in texture and cooking quality of the starch noodles produced from the different genotypes was found. It was sh...

Journal ArticleDOI
TL;DR: In this article, the power law relationship between radii of gyration and molecular weights was observed between the distribution of amylopectin in a mixture of mild and severe methods.
Abstract: Waxy maize starch was treated by a variety of gentle and severe methods: direct dispersion-solubilization into 90% dimethyl sulfoxide (DMSO) and H2O solvent, extrusion followed by dispersion-solubilization of the ground exudate into solvent, or jet-cooking or stirred autoclaving of an aqueous starch slurry followed by transfer into solvent Intrinsic viscosities [η] and multiangle light-scattering measurements were made in 90% DMSO-H2O A Mark-Houwink relation, [η] = (028–12) Mw029 ± 004, was obtained over a molecular weight range of ≈30–700 million However, there was a large amount of scatter in the data when [η] were >140 mL/g The power law relationship Rg ∝ Mw041±004 was noted between radii of gyration and molecular weights We infer from our data that over the entire range of Mw distributions, the amylopectin existed in solution as relatively compact molecules or aggregates and that in the higher molecular weight region, the size and possibly the shape of the “dissolved” amylopectin w

Journal ArticleDOI
TL;DR: In this paper, a wheat breeding program to introduce the low amylose character of Tanikei A6099 to elite lines, five waxy lines were unexpectedly obtained from 249 doubled haploid lines of the F1 hybrid.
Abstract: In our wheat breeding program to introduce the low amylose character of Tanikei A6099 to elite lines, five waxy lines were unexpectedly obtained from 249 doubled haploid lines of the F1 hybrid of Saikai 168 × Tanikei A6099. The amylose content of all the waxy lines was <1% and the blue value was <0.1. Starch granule-bound proteins were extracted and subjected to modified sodium dodecyl sulfate polyacrylamide gel electrophoresis. The waxy lines lacked the Wx protein. Starch paste viscosity measurements gave pasting profiles of waxy wheat starch that were quite different from those of nonwaxy wheats but similar to those of waxy maize. However, the peak viscosity of waxy wheats was much higher than that of the waxy maize.

Journal ArticleDOI
TL;DR: This study compares in the same experiment the β-glucan content of nine barley and 10 oat genotypes grown at two locations in each of two years (i.e., four environments) in North Dakota to find soluble β- glucancontent of oat groat was greater than barley, and oatGroat had a greater ratio of soluble-to-total β-Glucan than barley.
Abstract: The cholesterol-lowering effect of cereal grains has been associated with the soluble fiber component of dietary fiber. β-Glucan is the major soluble fiber component of barley (Hordeum vulgare L.) and oat (Avena sativa L.). Much research has been conducted to determine the β-glucan content of barley and oat genotypes from many different countries. However, genotypes of both crops always were grown in separate experiments, making direct comparisons between the two crops difficult. This study compares in the same experiment the β-glucan content of nine barley and 10 oat genotypes grown at two locations in each of two years (i.e., four environments) in North Dakota. Averaged across genotypes, total β-glucan content of barley and oat groat was similar. Soluble β-glucan content of oat groat was greater than barley, and oat groat had a greater ratio of soluble-to-total β-glucan than barley. The soluble β-glucan content and ratio of soluble to total β-glucan content of the “best” barley genotypes were l...

Journal ArticleDOI
TL;DR: In this article, the effects of the main metabolites, lactic and acetic acids, from the sourdough process on wheat doughs were tested with a dynamic sinusoidal oscillation test.
Abstract: The effects of the main metabolites, lactic and acetic acids, from the sourdough process on wheat doughs were tested with a dynamic sinusoidal oscillation test. Tests were done with a controlled stress rheometer. Dough treatment included four mixing times and four rest times before measurement. Phase angle, complex modulus, and viscosity were measured for all doughs at selected rest and mixing times, at frequencies ranging from 0.01–10 Hz. Results for all combinations of mixing and rest times were compared at 10 Hz. Effects of mixing time were most visible immediately after mixing and disappeared partially during rest time. Doughs that contained acid but no salt showed the clearest characteristics of overmixing, expressed by an increase in phase angle and decrease in complex modulus.

Journal ArticleDOI
TL;DR: In this paper, the authors examined the physicochemical properties of amylopectin in 14 rice varieties, including five Indica, five Japonica, and four waxy cultivars.
Abstract: Fourteen varieties of rice from Taiwan, including five Indica, five Japonica, and four waxy cultivars, were used in this study for the examination of fine structure and physicochemical properties of amylopectin. The results indicated that the amylopectin of Indica rice had lower molecular weight, lower average degree of polymerization (DP), and lower average chain number when compared to Japonica and waxy varieties. The shortest average DP was 6 glucose units for all 14 rice varieties. The average chain lengths (CL) of amylopectin were 18–22, 15–18, and 17–20 for Indica, Japonica, and waxy rice, respectively. Indica varieties with high amylose content had amylopectin that comprised a few extra long chains (DP >100). The CL distribution profiles of amylopectins for these 14 varieties could be divided into two factions: CL 10–15 and CL 40–44. Amylopectin of the Indica rice had a relatively high blue value and λmax, implying that a high proportion existed as long branches. The amylopectin of three I...

Journal ArticleDOI
TL;DR: A 7:3 mixture of wheat fiber (WF) and psyllium husk fiber (PHF) was substituted for 10wt% of flour on a 14% mb, and the protein in the blend was restored to 103% by incorporating vital wheat gluten.
Abstract: A 7:3 (w/w) mixture of wheat fiber (WF) and psyllium husk fiber (PHF) was substituted for 10wt% of flour on a 14% mb, and the protein in the blend was restored to 103% by incorporating vital wheat gluten After adding 05% sodium stearoyl 2-lactylate, the blend (100 g) was fortified with a combination of fat-coated ascorbic acid (AsA), proteinencased (PE) β-carotene, and cold-water-dispersible (CWD) all-rac-α-tocopheryl acetate (ToAc) at levels of 72, 56, and 115 mg, respectively, of active material Adding the fiber ingredients to the pup loaf formula increased water absorption 25% and mixing time 50% and imparted stickiness to the dough The fiber and antioxidant bread showed a 10% reduction in loaf volume and a somewhat inferior crumb grain with an off-color caused by small, black specks on a dark gray background The crumb of the fiber and antioxidant bread remained much softer than control bread during one to seven days of storage at room temperature Caramel coloring masked the off-color

Journal ArticleDOI
TL;DR: In this article, it was shown that the diameter of sugar-snap cookies was a function of spread rate and set time, and the differences in set time within cookies made with various hard wheat and soft wheat flours appeared to be affected by flour protein content.
Abstract: Time-lapse photography showed that, during baking, the diameter of sugar-snap cookies increased linearly then suddenly became fixed. Therefore, cookie diameter was a function of spread rate and set time. Cookies made with soft wheat flour were significantly larger in diameter (184 mm) than those made with hard wheat flour (161 mm). Cookies made with soft wheat flour set later (5.8 min) during baking than those made with hard wheat flour (5.1 min). The differences in set time within cookies made with various hard wheat flours or within cookies made with various soft wheat flours appeared to be affected by flour protein content. However, other factors also affected the difference in set time between cookies made with hard wheat and soft wheat flours. Cookies made with soft wheat flour spread at a faster rate (7.8 mm/min) than those made with hard wheat flour (4.6 mm/min). The level of soluble starch in the flour appeared to cause the difference in spread rate between cookies made with hard wheat an...