bluuebunny/crossref_metadata_2025_split huggingface dataset:
Controlled Stepwise Reduction of Disulfide Bonds and Heat‐Induced Modification of Wheat Dough Proteins
Authors: Xu Feng , Brown Kimberly M. , Dybdal Lone , Forman Todd M. , Fuglslang Claus C. , Wagner Peter 
Published: June 2007

ABSTRACTA reducing solution of 2‐mercaptoethanol and its oxidized form 2‐hydroxyethyl disulfide, whose variable concentrations set variable disulfide reduction potentials, was applied to progressively reduce the disulfide bonds of proteins extracted from doughs made from Meneba and Robin Hood flour. Several dough proteins had disulfide bonds stronger than those of other dough proteins. A SDS‐sedimentation method was applied to monitor the baking of dough into bread. Dough proteins susceptible to heat (baking) were studied by SDS‐fractionation, extraction with reducing alcoholic solution, SDS‐PAGE, and N‐terminal protein sequencing. High or low molecular weight glutenins, α, β, and γ‐gliadins, α‐amylase inhibitor, and α‐amylase trypsin inhibitor were identified among the dough proteins modified by heat (as shown by reduced solubility in aqueous‐SDS solution). The heat‐induced modification of the gliadins and glutenins might contribute to the coagulation of dough proteins, while the heat‐induced modification of the amylase or trypsin inhibitors might contribute to the regulation of endogenous or exogenous amylolytic or proteolytic activities in dough or bread.
Recovery of Lysine from Corn Steepwater
Authors: O'Brien Dennis J. , Craig James C. 
Published: June 2007

ABSTRACTOne approach to increasing the utilization of agricultural products is fractionation of low‐value materials to yield high‐value products. In this study, lysine recovery from corn steepwater, an internal processing stream generated in the wet‐milling of corn, was investigated. A weakly acidic cation exchange resin was employed to selectively recover lysine from corn steepwater at pH 7.0. In column studies, the product from the ion exchange operation had a lysine content of 4–6% (db). The only other amino acid in the product was arginine. The presence of sodium, potassium, and magnesium ions at significant concentrations in the steepwater limited the lysine content of the product because of competitive adsorption on the resin. The lysine‐enriched product reported here is 4–10 times higher in lysine content than other corn milling coproducts and could potentially be useful as a lysine supplement in animal feeds.
Determination of Bran Contamination in Wheat Flours Using Ash Content, Color, and Bran Speck Counts
Authors: Kim Y. S. , Flores R. A. 
Published: June 2007

ABSTRACTA fast new method based on image analysis, ScanPro Speck Expert (SPX), to determine the bran contamination in wheat flour was studied and compared with existing methods (air‐oven, ash, and color measurements) using an Agtron color meter and a Minolta chromameter. Twenty‐one hard red winter wheat flour samples with ash contents of 0.30–0.58% were collected from the Kansas State University pilot mill and used for this study. Intrinsic variability in the flour sample because of randomness of bran speck orientation and distribution in the sample holder could result in variation in the speck count. Simple and multiple linear regression analyses showed that estimation of flour ash content from the SPX results (R2 = 0.91) would be more accurate than the results from color measurements (R2 = 0.66 [Agtron color meter] and 0.74 [L*]). The added capability of SPX image analyzer to not only count the number of bran specks but also to measure their areas probably increases the accuracy of determining the bran contamination in wheat flour by image processing.
Some Physicochemical Properties of Small‐, Medium‐, and Large‐Granule Starches in Fractions of Waxy Barley Grain
Authors: Tang H. , Ando H. , Watanabe K. , Takeda Y. , Mitsunaga T. 
Published: June 2007

ABSTRACTBarley grain was divided into eight fractions from the surface layer to the center with a machine used to polish brewers' rice. Small‐, medium‐, and large‐granule starches were isolated from classified barley flour, and their physicochemical properties were investigated. The starch granules were oval to round with a median size of 2 μm for small, 10 μm for medium, and 12–19 μm for large granules. From the surface layer to the center, both the median sizes and the ratio of large granules decreased, and the ratio of medium‐ and small‐granules increased. The starches had A‐type X‐ray diffraction patterns typical of cereal starches. The moisture sorption showed a negative correlation to the granule size. The gelatinization temperatures of starch granules in each layer were approximately the same, but the enthalpies decreased in the order of large, medium, and small granules.
Dough Microextensibility Method Using a 2‐g Mixograph and a Texture Analyzer
Authors: Suchy J. , Lukow O. M. , Ingelin M. E. 
Published: June 2007

ABSTRACTDevelopment of a small‐scale method to measure dough extensibility, using a 2‐g mixograph and the TA.XT2 texture analyzer (TA) equipped with Kieffer rig, suitable for early‐generation wheat quality screening is presented. Three hook speeds 3.3, 7.0, and 10.0 mm/sec were tested on the TA. Only at the lower hook speed of 3.3 mm/sec were wheats, varying in quality, clearly differentiated. The ability to differentiate between wheats using the TA was compared with the Brabender Extensigraph. The sample ranking based on the resistance to extension (Rmax) from the TA at a hook speed of 10.0 mm/sec correlated highly (r = 0.99) to the ranking obtained on the extensigraph. Dough extensibility data from the extensigraph and the TA, using hook speed 10.0 mm/sec, was correlated (r = 0.90) to loaf volume. Similarly, dough extensibility on the TA, using hook speed 3.3 mm/sec, was correlated to loaf volume (r = 0.96). The effect of three dough water contents (farinograph absorption, farinograph absorption + 6%, and 2‐g mixograph water absorption) on physical properties of dough were evaluated by mixing the dough in a 2‐g mixograph and testing the extensibility on the TA. Dough prepared at farinograph absorption + 6% and at mixograph absorption allowed differentiation between wheats based on the resistance to extension (Rmax).
Effects of Commercial Hydrolytic Enzyme Additives on Canadian Short Process Bread Properties and Processing Characteristics
Authors: Harada O. , Lysenko E. D. , Preston K. R. 
Published: June 2007

ABSTRACTThe effects of increasing levels of eight commercial enzymes representing four types of fungal hydrolytic enzymes (α‐amylases, proteases, xylanases, and cellulases) on Canadian short process (CSP) bread quality and processing characteristics were studied. Addition of all enzymes types at optimum levels resulted in increased loaf volume and bread score and softer crumb. All four types of enzymes appeared to be equally effective in improving bread properties compared with the controls. At high levels, greater tolerance to the addition of xylanases and cellulases compared with the addition of α‐amylases and proteases was apparent. Mixing requirements increased with increasing levels of α‐amylase but no change was apparent with the other enzymes. Addition of all enzymes reduced sheeting work requirements, indicating a dough softening effect. Optimum bread properties for all enzymes were attained within a relatively narrow range of dough sheeting work values, which presumably correspond to optimum dough handling properties. The similarity in response of bread and sheeting characteristics at optimum levels of addition for all four enzyme types suggests a common nonspecific mechanism for improver action that is probably related to water release and the resulting impact on physical dough properties.
Effect of Processing, Formula and Measurement Variables on Alkaline Noodle Color—Toward An Optimized Laboratory System
Authors: Morris C. F. , Jeffers H. C. , Engle D. A. 
Published: June 2007

ABSTRACTA standardized laboratory method for assessing the color potential of flours for yellow alkaline (Cantonese) noodles is needed, especially for evaluating large numbers of small‐scale samples such as found in wheat breeding populations. To develop such a method, a number of processing and formula parameters were varied and judged for optimum level based on 1) discrimination and mean separation of flours, 2) sensitivity to minor variation in the protocol parameter, 3) practicality and simplicity for the technician, and 4) time efficiency. Four flours milled from single‐cultivar grain lots representing two with good and two with poor color potential were made into alkaline noodle sheets varying in thickness of 0.75–2.00 mm, water absorption of 33.0–39.0%, mixing time of 2–6 min, and NaCl levels of 0–4% (all flour weight basis). Commission Internationale de l'Eclairage (CIE) tristimulus color space (L*, a*, b*) values were measured at 0–24 hr using white, yellow, and black background tiles. Noodle sheet side and a dough resting period were examined. The flours themselves were a consistently large, significant source of variation for color, especially lightness (L*). Based on the optimization criteria, a noodle sheet thickness of 1.5–2.0 mm, an optimum to slightly over optimum water absorption (36% for the flours in this study) with some adjustment for protein content and dough handling properties, a mixing time of 4 min, no dough resting period, and 2% NaCl were selected. Color measurement at 24 hr on a white or otherwise light‐colored background tile was judged best using a consistent side of the noodle sheet. Resting doughs for 1 hr slightly improved handling and sheeting characteristics but was not included for time efficiencies.
Protein Content of Bulk Wheat from Near‐Infrared Reflectance of Individual Kernels
Authors: Delwiche Stephen R. , Hruschka William R. 
Published: June 2007

ABSTRACTProtein content of wheat by near‐infrared (NIR) reflectance of bulk samples is routinely practiced. New instrumentation that permits automated NIR analysis of individual kernels is now available, with the potential for rapid NIR‐based determinations of color, disease, and protein content, all on a single kernel (sk) basis. In the event that the protein content of the bulk sample is needed rather than that of the individual kernels, the present study examines the feasibility of estimating bulk sample protein from sk spectral readings. On the basis of 318 wheat samples of 10 kernels per sample, encompassing five U.S. wheat classes, the study demonstrates that with as few as 300 kernels bulk sample protein content may be estimated by sk NIR reflectance spectra at an accuracy equivalent to conventional bulk kernel NIR instrumentation.
Modeling Starch Gelatinization Kinetics of Milled Rice Flour
Authors: Ojeda Carlos A. , Tolaba Marcela P. , Suárez Constantino 
Published: June 2007

ABSTRACTMilled long‐grain rice samples were evaluated by differential scanning calorimetry (DSC) to determine the kinetics of starch gelatinization. The experiments were conducted with milled rice flour with a 10.6% degree of milling. DSC thermograms were obtained from 35 to 110°C using heating rates between 1°C/min and 15°C/min. The rate constants were evaluated, and two activation energies were found for different temperature ranges. At <70.1°C gelatinization was not completed. It was assumed that at <70.1°C gelatinization would only affect the amorphous regions. During the subsequent phase the crystalline regions destabilized by the amorphous component begin to gelatinize. For moisture content of 70%, wet basis, and a heating rate of 12°C/min, the enthalpy of gelatinization reaches a constant value of 7.3 J/g.
Stability and Dietary Contribution of Vitamin E Added to Bread
Authors: Ranhotra G. S. , Gelroth J. A. , Okot‐Kotber B. M. 
Published: June 2007

ABSTRACTDaily intake levels of vitamin E in the range of 200–800 IU are now recommended for its antioxidant effect. However, only vitamin E supplements or fortified foods may provide these high intake levels. As a fortified food, breads were prepared containing 200, 400, 800, or 1,600 IU of added vitamin E (dl‐α‐tocopheryl acetate) per pound loaf. These levels of fortification exerted no adverse effects on bread quality. However, only about two‐thirds of the added vitamin E was retained (recovered) in the breads, with retention values showing no further significant change during the seven‐day shelf‐life of the product. In fresh breads, vitamin E retention values were nearly the same (range 66.3–68.5%, average 67.2%) at all levels of vitamin E tested; this may hold true for levels not tested. Factoring in an average retention value of 67.2%, and actual potency (81.8%) of the vitamin E source used, a 50‐g serving of bread fortified with 1,600 IU of vitamin E per loaf would provide nearly one‐fourth of a suggested daily intake of 400 IU.
Effect of Kiln Drying on Falling Number of Oats
Authors: Kaarlehto T. , Salovaara H. 
Published: June 2007

ABSTRACTThe suitability of the falling number method for oats was studied using samples of oat groats, oat bran, oat endosperm flour, and rolled oats. Sample sizes of 4.5–8 g were tested. The results showed that a standard 7‐g sample falling number determination would be suitable for oats, the falling number of samples varying from 328 to 721 sec. Due to high gelatinization temperature of oat starch, falling number values <300 sec showed greater variation than those >300 sec. Oat groat samples from two separate kiln drying processes showed that kiln drying increased the falling number values by 30–89%. The falling number determination is a potential tool for estimating the adequacy of kiln drying of oats. However, further modifications of the method should be developed to better consider the pasting properties of oat starch.
Convenient Method to Determine Free Fatty Acid of Rice Using Thin‐Layer Chromatography and Flame‐Ionization Detection System
Authors: Nishiba Yoichi , Sato Tetsuo , Suda Ikuo 
Published: June 2007

ABSTRACTA convenient method which possessed simplicity and high sensitivity was designed to investigate the changes in free fatty acid (FFA) of rice during storage using a thin‐layer chromatography and flame‐ionization detection (TLC/FID) system. In this method, two different solvent systems for TLC were used according to the purpose of experiments. Solvent system A (hexane and diethyl ether and acetic acid 80:20:1) was suitable to obtain a chromatogram showing the overall state of rice lipid degradation. Using solvent system A, the degradation of triglyceride or the increase in FFA during storage was clearly visualized as changes in the chromatogram. Solvent system B (hexane and acetic acid 100:1) was used to improve the low reproducibility of the TLC/FID method. When methyl stearate was used as an internal standard with solvent system B, high reproducibility of the FFA value was obtained, and very small changes were detectable in stored white milled rice. This method has small sample size and simple operation and is more sensitive than the standard titration method. Therefore, this seems to be an especially convenient method for small‐scale storage tests or for experiments using many samples.
Relationship of Kernel Size to Flour Water Absorption for Canada Western Red Spring Wheat
Authors: Morgan B. C. , Dexter J. E. , Preston K. R. 
Published: June 2007

ABSTRACTCanada Western Red Spring (CWRS) wheat exhibits consistent positive relationships between kernel weight and farinograph and baking water absorption. These relationships are sufficiently robust to be statistically significant (P < 0.05) for historical Canadian Grain Commission harvest survey data generated one year apart for 17 years, and for historical data on individual cultivars in advanced Canadian wheat breeding trials, also generated annually. Verification of the relationships were obtained by analyzing different kernel size fractions obtained by sieving CWRS harvest survey samples and pure CWRS cultivars from various origins. In all cases, highly significant positive relationships were observed between kernel size and water absorption. The relationships were evident for individual streams from pilot‐scale millings of sized fractions from CWRS harvested in two different years. Strong correlations of kernel weight to farinograph and baking absorption also were shown for sized fractions from commercial samples of American Dark Northern Spring and Australian Prime Hard wheat. The strong statistical association between kernel size and water absorption could not be explained on the basis of wheat hardness (flour starch damage), protein content, or dough strength. In view of the importance of flour water absorption to bakers, further investigation is warranted to identify the cause for the association between large kernel size and high water absorption.
Viscoelasticity of Cowpea Starch Gels
Authors: Won So‐Yoon , Choi WonSeok , Lim Hyesook S. , Cho Ki‐Yul , Lim Seung‐Taik 
Published: June 2007

ABSTRACTThe mechanical behavior of cowpea starch gels (10%, w/v) at small and large deformations were investigated in comparison with acorn, corn, and potato starches in storage at 4°C for seven days. The rapid viscograms of starch paste (7%, w/v) revealed that cowpea starch had a larger setback (1,135 cP) than other starches (465–830 cP), although peak viscosity (1,723 cP) and pasting temperature (76°C) were between those of corn and potato starches. Texture profile analysis of cowpea starch gel showed exceptionally higher values for hardness, gumminess, chewiness and initial modulus than other starch gels. Cowpea starch gel also exhibited higher G′ and smaller tan δ compared with other starch gels, regardless of the storage time. A creep test revealed that the cowpea starch gel could remain highly resistant to stress, showing the least deformation among the tested starch gels during storage up to seven days. The overall results disclosed that cowpea starch was capable of forming exceptionally strong and elastic gels with good storage stability.
Extrusion of Cross‐Linked Hydroxypropylated Corn Starches II. Morphological and Molecular Characterization
Authors: McPherson A. E. , Jane J. 
Published: June 2007

ABSTRACTA series of cross‐linked hydroxypropylated corn starches were extruded with a Leistritz micro‐18 co‐rotating extruder. Extrusion process variables including moisture (30, 35, and 40%), barrel temperature (60, 80, and 100°C), and screw design (low, medium, and high shear) were investigated. Scanning electron microscopy (SEM) of extruded starches showed a gel phase with distorted granules and granule fragments after extrusion at 60°C. After extrusion at 100°C only a gel phase was observed with no granular structures remaining. High performance size exclusion chromatography (HPSEC) equipped with multiangle laser light‐scattering (MALLS) and refractive index (RI) detectors showed extruded starches degraded to different extents, depending on extrusion conditions. The average molecular weight of the amylopectin of unextruded native corn starch was 7.7 × 108. Extrusion at 30% moisture, 100°C, and high shear reduced the molecular weight of amylopectin to 1.0 × 108. Hydroxypropylated normal corn starch extruded at identical conditions showed greater decreases in amylopectin molecular weight. With the addition of cross‐linking, the amylopectin fractions of the extruded starches were less degraded than those of their native and hydroxypropylated corn starch counterparts. Similarly, increasing moisture content during extrusion lowered amylopectin degradation in the extruded starches. Increasing temperature during extrusion of cross‐linked hydroxypropylated starches at high moisture content (e.g., 40%) lowered amylopectin molecular weights of the extruded starches, whereas increasing extrusion temperature at low moisture content (30%) resulted in less degraded molecules. This difference was attributed to the higher glass transition temperatures of the cross‐linked starches.
Study of Internal Structure of Waxy Wheat Starch Granules by KI/I2 Solution
Authors: Seguchi Masaharu , Yasui Takeshi , Hosomi Kazuko , Imai Tooru 
Published: June 2007

ABSTRACTWheat starch granules were separated from waxy wheat flour by the acetic acid (pH 3.5) fractionation technique. Waxy wheat starch samples were stained red‐brown using KI/I2 solution. Subsequently, the concentration of the KI/I2 solution was increased to >2.5% KI and 1.0% I2. Then the appearance of the waxy wheat starch granules quickly became ghostlike. The internal structure of the ghost could be observed. This structure consisted of two parts with different colors: a red‐brown central part and a slightly pinkish surrounding part. Sonication of the ghost at 20 kHz for 20 sec separated the central part from the surrounding part. Each of the separated parts were subjected to gel‐filtration chromatography, and their chromatography profiles indicated only amylopectin and no amylose. The central and surrounding parts had molecular weights of 54.3 × 105 and 23.8 × 106 from Berry plots, respectively.
Influence of Sprout Damage on Oriental Noodle Appearance as Assessed by Image Analysis
Authors: Hatcher D. W. , Symons S. J. 
Published: June 2007

ABSTRACTFresh alkaline (kansui) and white salted noodles prepared from sound and sprout damaged patent flours of the western Canadian wheat class Canadian Prairie Spring White (CPSW) cv. Vista were characterized by image analysis (IA). In all samples, the number of discolored spots increased with aging <24 hr (24 ± 1°C), although the number of spots per sample was significantly influenced by the degree of sprout damage. Alkaline kansui noodles made from severely sprouted wheat (Day 5) flours had the greatest number of spots per image at 1 hr (114) and increased to 256 spots per image by 7 hr. This represented an approximate fivefold greater number of spots as compared with the sound flour kansui noodle at 7hr. No further increase in spot numbers was detected in the severely sprouted sample with aging for 24 hr. Significantly fewer spots were observed in the white salted noodles (WSN) prepared from heavily sprouted wheat with 29 spots per image at 1 hr increasing to only 54.5 after 24 hr. The IA system was able to detect a significant difference in the size of the discolored spots over time due to sprout damage. The largest spot size was measured in the kansui noodles prepared from heavily sprouted wheat. All sprouted flours used to prepare both kansui and WSN had significantly larger spot sizes as compared with sound control flours. The mean darkness values for the noodle spots prepared from the heavily sprouted flours were significantly darker than the control flours for both WSN and kansui noodles. Spots of all noodles were characterized by darkness distribution profiles that highlighted key differences between noodle type and the degree of sprout damage. Addition of sodium metabisulfite to the kansui noodles at 1,000 ppm significantly decreased the number of spots formed, minimized the size, and lightened the spots over the first 7 hr, but they subsequently darkened after 24 hr.
Variability in a Starch Isolation Method and Automated Digital Image Analysis System Used for the Study of Starch Size Distributions in Wheat Flour
Authors: Bechtel Donald B. , Wilson Jeff 
Published: June 2007

ABSTRACTA starch isolation method and digital image analysis system were developed to accurately measure size distributions of the starch populations in wheat. The image analysis system was coupled directly to a light microscope equipped with computer controlled step stage and automatic focus. Automation of data acquisition and processing eliminated some of the labor intensive steps previously required for analyzing starch granule size distributions. This system was used to standardize starch isolation methods and compare variation and precision of the system. Operational variations were determined and statistically assessed. The number of fields of view required for low standard errors and acceptable speed of analysis was determined to be fifty. A major advantage of the system has been the increased resolution. The use of higher magnifications and stage automation allowed the analysis of starch granules as small as 0.84 μm in diameter while analyzing thousands of starch granules per sample.