bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Wheat Starch and Gluten on Tortilla Texture
Authors: Wang Linfeng , Flores Rolando A.
Published: June 2007

Wheat starches were isolated from three wheat flours. Two vital wheat glutens, one from a commercial source and another one isolated from straight‐grade flour, were combined with wheat starches to form reconstituted flours with a protein level of 10%. Several characteristics of tortillas made with the hot‐press method were measured. No significant difference (P < 0.05) occurred in texture of tortillas made with hard wheat gluten and soft wheat gluten. Wheat starches did not have any significant (P < 0.05) effect on tortilla stretchability or foldability. Analysis of variance confirmed that wheat starch and gluten had limited effects on tortilla texture. The possible reasons were that the solubles of wheat flour were not included, and the shortening in the tortilla formula interfered with the interaction of gluten and starch.
Effects of Wheat Bug (Eurygaster maura) Protease on Glutenin Proteins
Authors: Sivri D. , Sapirstein H. D. , Köksel H. , Bushuk W.
Published: June 2007

Proteolytic degradation of 50% 1‐propanol insoluble (50PI) glutenin of six common wheat cultivars by wheat bug (Eurygaster maura) protease was investigated using reversed‐phase HPLC. Wheat at the milk‐ripe stage was manually infested with adult bugs. After harvest, bug‐damaged kernels were blended (2:1, kernel basis) with undamaged grain of the same cultivar. Samples of ground wheat were incubated in distilled water for different times (0, 30, 60, and 120 min). The incubated whole meal samples were subsequently freeze‐dried and stored until analysis. The degree of proteolytic degradation of 50PI glutenin was determined based on the quantity of total glutenin subunits (GS), high molecular weight GS (HMW‐GS), and low molecular weight GS (LMW‐GS). For ground wheat samples incubated for ≥30 min, 50PI glutenin was substantially degraded as evidenced by a >80% decrease on average in total GS, HMW‐GS, and LMW‐GS. Some cultivars showed different patterns of glutenin proteolysis as revealed by differences in the ratios of HMW‐GS to LMW‐GS between sound and bug‐damaged samples; a significant decrease in this ratio was found for four cultivars. This evidence, combined with other observations, indicated that there were intercultivar differences in polymeric glutenin resistance to the protease of the wheat bug Eurygaster maura. While the nature of this resistance is unknown, it should be possible to select and develop wheat cultivars with improved tolerance for wheat bug damage. Propanol insoluble glutenin, which corresponds to relatively large glutenin polymers, appears to be an excellent quantitative marker for this purpose.
Potential Use of Raman Spectroscopy for Determination of Amylose Content in Maize Starch
Authors: Lee Phillips David , Xing Jie , Liu Huijun , Pan Duo‐Hai , Corke Harold
Published: June 2007

An analytical method using Raman spectroscopy was developed for the determination of amylose concentration in maize starches. FT‐Raman spectra of four maize starches with amylose content varying from 3.3 to 66% were obtained. A Raman band at ≈1657 cm‐1 correlated linearly with amylose concentration in the four maize starches, and a calibration curve for Raman band intensity versus amylose content was developed. The linear correlation of the I1657/I900 integrated areas with amylose content was r = 0.997. The Raman‐based calibration curve allows fast and nondestructive determination of the amylose content in maize starches with minimal sample preparation.
Effect of Corn Oil on Thin Stillage Evaporators
Authors: Singh V. , Panchal C. B. , Eckhoff S. R.
Published: June 2007

Removal of the germ at the front end of the dry‐grind ethanol process using the Quick Germ process reduces the amount of oil in thin stillage. Thin stillage with 4–6% solids is dewatered to 25–30% solids by evaporation. Thin stillage evaporators in a dry‐grind ethanol plant foul and have to be periodically taken down for maintenance and cleaning. Fouling caused by thin stillage containing different amounts of oil was studied using an annular fouling probe. It was determined that the rate of fouling in a drygrind ethanol plant is three times higher when compared with that in a wet‐milling ethanol plant. The addition of oil to wet‐milled thin stillage significantly affected the rate of fouling. Fouling resistance increased with an increase in oil concentration for wet‐milled thin stillage up to a concentration of 1.41%. At a concentration of 1.47%, the rate of fouling decreased. As the concentration of oil increased in dry‐grind ethanol thin stillage, the rate of fouling decreased. These results suggest that the Quick Germ process will reduce the rate of heat transfer equipment fouling in a drygrind ethanol plant, which will decease capital costs and maintenance costs.
Segregating Hard Red Winter Wheat into Dough Factor Groups Using Single Kernel Measurements and Whole Grain Protein Analysis
Authors: Baker Scott , Herrman Timothy J. , Loughin Thomas
Published: June 2007

In accordance with the Grain Quality Acts of 1986 and 1990, scientists at Kansas State University are studying the feasibility of implementing a quality‐based marketing system for hard red winter (HRW) wheat in the Southern Plains. This research addresses the development of a segregation system that uses the single kernel characterization system and the whole grain near‐infrared analyzer to evaluate the milling and baking quality of wheat as a single value called “dough factor”. This single value represents the amount of flour‐water dough that can be produced from a given unit of wheat. Samples of HRW wheat (≈100 per location) were collected at five Kansas country elevators during the 1995 and 1996 harvests. After the dough factor was measured for individual samples, the samples were composited into seven dough factor groups to establish binning and segregation strategies and to explore the relationship between wheat quality measurements and dough factor groups. Results showed that dough factor groups were significantly different from each other and that dough factor groups were related (P < 0.05) to increases in test weight, single kernel weight, single kernel size, flour yield, and mixing time. Although locations showed year‐to‐year variability for test weight, kernel weight, and kernel size, the differences among dough factor groups for these characteristics across locations were consistent, indicating that the mean values within dough factor groups are similar regardless of location. The lack of significant differences in protein content among dough factor groups was attributable to high variability within dough factor groups between years. High protein values were present in low and high dough factor groups, indicating that protein content alone is not a good indicator of wheat quality. Patterns of differences in wheat quality characteristics among dough factor groups suggest that the seven groups studied can be reduced to three groups: <107, 107–112.9, ≥113. This study demonstrates that dough factor as a segregation and marketing tool is related to single kernel characteristics, differentiates wheats of varying quality, and reflects the end‐use value of wheat.
Optimizing the SDS Sedimentation Test for End‐Use Quality Selection in a Soft White and Club Wheat Breeding Program
Authors: Carter Brady P. , Morris Craig F. , Anderson James A.
Published: June 2007

Soft white and club wheat (Triticum aestivum L.) market subclasses have specific end‐use characteristics. Among the most important of these characteristics are weak dough mixing and handling properties as a result of weak gluten. The SDS sedimentation test has gained wide acceptance as a useful, small‐scale test in bread wheat breeding programs to predict gluten strength and baking quality. To optimize its use for soft white or club wheat breeding, variations of the SDS sedimentation test were performed on grain from winter wheats grown at eight locations in the U.S. Pacific Northwest, and the effects of lines, environment, and their interactions on SDS sedimentation volumes were determined. Using different sample weights and substituting whole meal for flour did not affect the ability of the SDS sedimentation test to differentiate among lines. Changes in protein concentration and sample weight caused proportional changes in SDS sedimentation volumes; however, the response was not consistent among all lines. Line had a greater effect on the SDS sedimentation volumes than any other source of variation. If differential effects of protein to SDS sedimentation among lines are taken into account, the SDS sedimentation test should be an effective small‐scale test for end‐use quality assessment in soft white and club wheat breeding programs.
Role of Starch Granules in Controlling Expansion of Dough During Baking
Authors: Kusunose Chiharu , Fujii Toshiko , Matsumoto Hiroshi
Published: June 2007

The role of starch granules in the expansion of doughs during baking was investigated using artificial flours made from dry vital wheat gluten and wheat starch, potato starch, or tapioca starch. The three starches were selected because of their diverse gelatinization properties. Baking tests on flour from tapioca starch gave the largest loaf volume and the most extensive postbaking shrinkage. Potato starch flour gave the smallest volume and the least shrinkage. Amylograph test data, dough expansion under decreased pressure, progress of expansion during baking, and scanning electron microscopy revealed the role starch granules play in ideal baking conditions. Starch granules should not gelatinize early in the baking cycle as potato starch does but should gelatinize later in the baking cycle as wheat starch does. This prevents early setting of the dough which inhibits expansion. Starch granules should not disrupt and fuse together during gelatinization as tapioca starch does, forming an impermeable gas membrane. Granules should gelatinize individually as wheat starch does, causing a disruption of cell membranes which prevents shrinkage of the loaf during cooling after baking.
α‐Amylolysis of Large Barley Starch Granules
Authors: Lauro M. , Forsell P. M. , Suortti M. T. , Hulleman S. H. D. , Poutanen K. S.
Published: June 2007

The α‐amylolysis of large (volume average 16 μm) barley starch granules was studied by measuring the amount of carbohydrates solubilizing during hydrolysis, and the changes in morphology and molecular structure of the granule residues by scanning electron microscopy, particlesize analysis, size‐exclusion chromatography, X‐ray diffraction, and differential scanning calorimetry. X‐ray diffraction showed that, in the earlier stages of α‐amylolysis, both amorphous and crystalline parts of the granules were equally solubilized. More extensive hydrolysis caused a gradual decrease in A‐type crystallinity and degradation of the granular structure. Scanning electron microscopy revealed that hydrolysis proceeded through pinholes, and pitted and partially hollow granule residues were formed. The lipid‐complexed amylose was less susceptible to α‐amylolysis than free amylose and amylopectin. Lipid‐complexed amylose started leaching out of the granule residues only after half of the starch had solubilized due to the α‐amylase treatment. Even though scanning electron microscopy indicated that there were intact granules left throughout the hydrolysis, the results obtained suggested that α‐amylolysis of large barley starch granules proceeded rather evenly among the granules.
Physical Properties and Enzymatic Digestibility of Phosphorylated ae, wx, and Normal Maize Starch Prepared at Different pH Levels
Authors: Liu Huijun , Ramsden Lawrence , Corke Harold
Published: June 2007

Phosphorylated starches were prepared with sodium tripolyphosphate (STPP) at pH 6, 8, and 10 from waxy (wx, 3.3% amylose), normal (22.4% amylose), and two high‐amylose (ae, 47 and 66% amylose) maize starches. After phosphorylation, the gelatinization peak temperature (Tp) decreased and pasting peak viscosity (PV) increased for all the starches except wx, which showed a slight increase in gelatinization temperature. There was a substantial effect of phosphorylation pH on paste viscosity. More crosslinking was found in ae starches with phosphorylation at pH 10. Sodium ions apparently decreased PV of all the phosphorylated starches while only slightly affecting PV of native starches. Phosphorylation increased swelling power of some of the starches, with maximum swelling power at phosphorylation pH 8 and minimum at pH 10. Maximum swelling power for wx starch after preparation was at pH 8 and minimum at pH 6. After phosphorylation, the clarity and freeze‐thaw stability of all the starches was greatly increased compared with the native starches. Phosphorylation increased digestibility of ae starches but had little effect on wx and normal starches. After phosphorylation, the adhesiveness, springiness, and cohesiveness of all starch gels generally increased, the hardness of 47% ae and wx starches increased, and that of normal starches decreased. Enthalpy of gelatinization decreased after phosphorylation with the greatest decrease observed for ae starches. When the phosphorylation pH increased from 6 to 10, the brightness (L*) of all the phosphorylated starches decreased, while a* and b* of all the phosphorylated starch increased. Scanning electron micrographs showed some erosion on the surface of starch granules after phosphorylation.
Effect of Amylose Content on Gelatinization, Retrogradation, and Pasting Properties of Starches from Waxy and Nonwaxy Wheat and Their F1 Seeds
Authors: Sasaki Tomoko , Yasui Takeshi , Matsuki Junko
Published: June 2007

We studied the effect of amylose content on the gelatinization, retrogradation, and pasting properties of starch using wheat starches differing in amylose content. Starches were isolated from waxy and nonwaxy wheat and reciprocal F1 seeds by crossing waxy and nonwaxy wheat. Mixing waxy and nonwaxy wheat starch produced a mixed starch with the same amylose content as F1 seeds for comparison. The amylose content of F1 seeds ranged between waxy and nonwaxy wheat. Nonwaxy‐waxy wheat had a higher amylose content than waxy‐nonwaxy wheat. Endothermic enthalpy and final gelatinization temperature measured by differential scanning calorimetry correlated negatively with amylose content. Gelatinization onset and peak temperature clearly differed between F1 and mixed starches with the same amylose content as F1 starches. Enthalpy for melting recrystallized starches correlated negatively with amylose content. Rapid Visco Analyser measurement showed that F1 starches had a higher peak viscosity than waxy and nonwaxy wheat starches. Mixed starches showed characteristic profiles with two low peaks. Setback and final viscosity correlated highly with amylose content. Some of gelatinization and pasting properties differed between F1 starches and mixed starches.
Oil Absorption Characteristics of a Multigrain Extrudate During Frying: Effect of Extrusion Temperature and Screw Speed
Authors: Osman M. G. , Sahai D. , Jackson D. S.
Published: June 2007

The oil absorption characteristics of a multigrain extruded and fried snack product were studied as a function of extruder screw speed and cooking temperature using a central composite response surface methodology (RSM). The extruded product was produced using a corotating twin screw extruder, dehydrated to a uniform moisture content, and subsequently deep‐fat‐fried at 192 ± 1°C for 10–40 sec to complete expansion. Significant RSM models were developed for oil absorption and extrudate water absorption index (WAI). According to the lowest oil model, absorption (19.9%) was obtained with an extruder screw speed of 218.6 rpm and a cooking temperature of 117.8°C. WAI reached a maximum at a screw speed of 221.9 rpm and a cooking temperature of 109°C. Oil absorption characteristics and extrudate WAI were significantly correlated (r= ‐0.84, P = 0.0002). The data suggest that extrusion conditions can be optimized to influence the physicochemical structures in the extrudate matrix so that oil absorption can be minimized.
Composition and Utilization of Barley Pearling By‐Products for Making Functional Pastas Rich in Dietary Fiber and β‐Glucans
Authors: Marconi E. , Graziano M. , Cubadda R.
Published: June 2007

Pearling by‐products and the pearled products of two commercial stocks of hulled barley, pearled according to an industrial process consisting of five consecutive pearling steps, were analyzed for β‐glucans, dietary fiber (total, soluble, and insoluble), protein, lipid, ash, and digestible carbohydrate. The data showed that the pearling flour fractions, abraded in the fourth and fifth hullers, contained interesting amounts of β‐glucans (3.9–5.1% db) from a nutritional point of view. These fractions were subsequently enriched in β‐glucans using a milling‐sieving process to double β‐glucan content (9.1–10.5% db). Functional pastas, enriched with β‐glucans and dietary fiber, were produced by substituting 50% of standard durum wheat semolina with β‐glucan‐enriched barley flour fractions. Although darker than durum wheat pasta, these pastas had good cooking qualities with regard to stickiness, bulkiness, firmness, and total organic matter released in rinsing water. The dietary fiber (13.1–16.1% wb) and β‐glucan (4.3–5.0% wb) contents in the barley pastas were much higher than in the control (4.0 and 0.3% wb, respectively). These values amply meet the FDA requirements of 5 g of dietary fiber and 0.75 g of β‐glucans per serving (56 g in the United States and 80 g in Italy). At present, the FDA has authorized the health claim “may reduce the risk of heart disease” for food containing β‐glucans from oat and psyllium only.
Distribution of β‐Glucan in the Grain of Hull‐less Barley
Authors: Zheng G. H. , Rossnagel B. G. , Tyler R. T. , Bhatty R. S.
Published: June 2007

Nine hull‐less barley (HB) containing waxy (0–7% amylose), normal (≈25% amylose), or high amylose (≈42% amylose) starch with normal or fractured granule make‐up and 4–9% (1→3)(1→4)‐β‐d‐glucans (β‐glucan) were pearled to remove 70% of the original grain weight in 10% intervals. The pearled fractions were analyzed for β‐glucan distribution within HB grain. Protein content of the pearled fractions indicated that the three outermost fractions contained pericarp and testa, aleurone, and subaleurone tissues, respectively. For all HB, β‐glucan and acid‐extract viscosity were very low in the outermost 20% of the kernel. For low β‐glucan HB, β‐glucan content was the greatest in the subaleurone region and declined slightly toward inner layers. For high β‐glucan HB, however, more than 80% of grain β‐glucan was distributed more evenly throughout the endosperm. Acid extract viscosity was significantly (P < 0.01) correlated with total (r = 0.75) and soluble (r = 0.87) β‐glucan content throughout the kernel of all HB. Growing conditions, location and year, had significant effects on the concentration of protein, starch and β‐glucan. However, protein, starch, and β‐glucan distribution patterns were not affected by growing conditions. The difference in β‐glucan distribution between low and high β‐glucan HB may explain the difference in milling performance of HB with low or high β‐glucan.
Genotypic and Environmental Effects on Oat Milling Characteristics and Groat Hardness
Authors: Doehlert Douglas C. , McMullen Michael S.
Published: June 2007

The production of oat bran involves the dehulling of oats, inactivation of their enzymes, and the subsequent grinding and sieving of the clean groats to isolate the larger bran particles. The bran yield from the oat groats may be related to their hardness, as it is in wheat. Groat breakage, which occurs during the dehulling process, reduces milling yield and may also be related to groat hardness. This study sought to investigate genotypic and environmental effects on oat dry milling and oat dehulling characteristics, and attempted to define properties associated with oat groat hardness. Significant genotypic differences in bran yield were largely attributed to groat composition, where higher β‐glucan and oil concentrations in the groat were associated with higher bran yields. Bran composition was largely dependent on a combination of the bran yield and the groat composition. Although groat breakage was correlated with bran yield and with groat β‐glucan concentration, environmental factors appeared to be more influential. Locations that had suffered severe crown rust infestations exhibited higher rates of groat breakage during dehulling. Bran yield was not as strongly affected at the locations infested with crown rust, indicating that bran yield and groat breakage are manifestations of different types of groat hardness and are only partially related.
Differentiating Vitreous and Nonvitreous Durum Wheat Kernels by Using Near‐Infrared Spectroscopy
Authors: Dowell F. E.
Published: June 2007

The vitreousnss of durum wheat is used by the wheat industry as an indicator of milling and cooking quality. The current visual method of determining vitreousness is subjective, and classification results between inspectors and countries vary widely. Thus, the use of near‐infrared (NIR) spectroscopy to objectively classify vitreous and nonvitreous single kernels was investigated. Results showed that classification of obviously vitreous or nonvitreous kernels by the NIR procedure agreed almost perfectly with inspector classifications. However, when difficult‐to‐classify vitreous and nonvitreous kernels were included in the analysis, the NIR procedure agreed with inspectors on only 75% of kernels. While the classification of difficult kernels by NIR spectroscopy did not match well with inspector classifications, this NIR procedure quantifies vitreousness and thus may provide an objective classification means that could reduce inspector‐to‐inspector variability. Classifications appear to be due, at least in part, to scattering effects and to starch and protein differences between vitreous and nonvitreous kernels.
Temperature‐Induced Changes in the Dynamic Rheological Behavior and Size Distribution of Polymeric Proteins for Glutens from Wheat Near‐Isogenic Lines Differing in HMW Glutenin Subunit Composition
Authors: Lefebvre J. , Popineau Y. , Deshayes G. , Lavenant L.
Published: June 2007

Viscoelasticity of hydrated gluten depends on composition of HMW gluten subunits (GS), size distribution of glutenin polymers, and proteinprotein interactions. Glutens extracted from four near‐isogenic lines with differing HMW‐GS were analyzed. Rheological properties were studied by dynamic assay in shear. Size distribution of prolamins was determined by sequential extraction and size‐exclusion HPLC. Assays performed at 20°C confirmed that viscoelasticity was determined by large glutenin polymers. The abundance of large glutenin polymers depended on the HMW‐GS composition of the lines. Difference of functionality linked to subunit structure was highlighted by comparing the behaviors of the 1A/1B null and 1A/1D null lines. Glutens were submitted to heating and cooling cycles, with or without an SH‐blocking agent (N‐ethylmaleimide [NEMI]). At 20–40°C, no irreversible changes of the mechanical properties occurred. Thermal treatment affected chain mobility, and possibly H bonds, but not the chemical structure of the network. At >40°C, irreversible rheological changes were observed without NEMI. Irreversibility was mainly due to chemical modifications affecting the polymer size distribution through SH‐SS exchange reactions. The sensitivity of gluten to temperature depended on subunit composition.
Dry Matter Loss During Nixtamalization of a White Corn Hybrid: Impact of Processing Parameters
Authors: Sahai D. , Surjewan I. , Mua J. P. , Buendia M. O. , Rowe M. , Jackson D. S.
Published: June 2007

Nixtamalization is the primary step in the production of products such as corn chips, tortilla chips, tacos, and corn tortillas. The process involves cooking and steeping of corn in lime and excess water to produce nixtamal. Commercial nixtamalization results in 5–14% corn solids loss in the liquid generated during cooking‐steeping and washing. Loss of corn solids not only causes economic loss to corn processors but also creates costly waste and wastewater disposal problems. Empirical results show that, besides corn kernel characteristics, processing parameters are critical variables influencing corn solids loss and effluent pH during nixtamalization. This work was designed to systematically study the impact of processing parameters on corn dry matter loss and effluent pH generated during nixtamalization by using response surface methodology. Corn cooking temperature and lime concentration were more critical factors influencing corn solid loss than were cooking and steeping time. In the ranges studied, total dry matter loss increased only up to ≈8 hr of steeping and then leveled off. By optimizing the nixtamalization protocol, effluent dry matter loss can be minimized.
Molecular Structure and Some Physicochemical Properties of High‐Amylose Barley Starches
Authors: Yoshimoto Yasushi , Tashiro Jyunko , Takenouchi Tadahiro , Takeda Yasuhito
Published: June 2007

The molecular structure and some physicochemical properties of starches from two high‐amylose cultivars of barley, high‐amylose Glacier A (HAG‐A) and N (HAG‐N), were examined and compared with those of a normal cultivar, Normal Glacier (NG). The true amylose contents of HAG‐A, HAG‐N, and NG were 41.0, 33.4, and 23.0%, respectively. Iodine affinities before and after defatting of starch, and thermograms of differential scanning calorimetry, indicated that HAG‐A and HAG‐N starches had a higher proportion of amylose‐lipid complex than did NG starch. The amylopectins from HAG‐A and HAG‐N were similar to NG amylopectin in average chain length (18–19), β‐amylolysis limit (β‐AL 56–57%), number‐average degrees of polymerization (DPn 6,000–7,500) and chain length distribution. Very long chains (1–2%) were found in amylopectins from all cultivars. HAG‐A amylopectin had a larger amount of phosphorus (214 ppm) than the others. The amyloses from HAG‐A and HAG‐N resembled NG amylose in DPn (950–1,080) and β‐AL (70–74%). However, HAG‐A and HAG‐N had a larger number of chains per molecule (NC 2.4–2.7) than NG amylose (1.8) and contained the branched amylose with a higher NC (9.5–10.6) than that of NG amylose (5.8), although molar fractions of the branched amylose (15–20%) were similar.
Utilization of Calcium in Breads Highly Fortified with Calcium as Calcium Carbonate or as Dairy Calcium
Authors: Ranhotra G. S. , Gelroth J. A. , Leinen S. D.
Published: June 2007

White pan breads were prepared with flour highly fortified with calcium (Ca), using Ca carbonate (Ca, 38.8%) or a high Ca whey powder (Ca, 5.6%) as the Ca source; bread was also prepared using Ca carbonate plus lactose. Ca was added to flour at 924 mg/100 g of flour, a level 4.4 times higher than specified under the U.S. enrichment standards. Breads were dried and finely ground to prepare test diets (Ca, 0.5%) which were then fed to growing rats for four weeks (growth phase) or eight weeks (approaching maturity). At either interval, femur ash content, femur Ca content, femur strength, or Ca absorption values did not differ significantly among groups fed breads fortified either with Ca carbonate, Ca carbonate + lactose, or whey. Thus, breads can be highly fortified with Ca carbonate to be labeled as “high” in Ca, and this Ca may be as well absorbed and utilized as dairy Ca.
Extrusion of Cross‐Linked Hydroxypropylated Corn Starches I. Pasting Properties
Authors: McPherson A. E. , Bailey T. B. , Jane J.
Published: June 2007

A series of cross‐linked (0, 0.014, 0.018, 0.024, and 0.028% POCl3, dry starch basis) hydroxypropylated (8%) corn starches were extruded using a Leistritz micro‐18 co‐rotating extruder. Process variables included moisture, barrel temperature, and screw design. Differential scanning calorimetry and X‐ray diffraction studies showed the level of starch crystallinity decreased with increasing severity of extrusion conditions. Pasting properties of the extruded starches were examined using a Rapid Visco Analyser. Pasting profiles of starches extruded at different conditions displayed different hot paste viscosity and final viscosity. Increasing starch moisture content during extrusion and level of cross‐linking increased starch viscosity (P < 0.0001), whereas increasing extrusion temperature and shear decreased starch viscosity (P < 0.0001). Interactions were found between level of cross‐linking and screw design and between extrusion temperature and starch moisture content (P < 0.0001).
Immunocytochemical Localization of Gluten Proteins Uncovers Structural Organization of Glutenin Macropolymer
Authors: Lindsay Megan P. , Skerritt John H.
Published: June 2007

The content and composition of the disulfide‐bonded glutenin macropolymer has been shown to influence dough properties, although its structural organization is poorly characterized. The structure of the glutenin macropolymer in dough was studied using an immunolocalization transmission electron microscopy (TEM) technique by localizing gliadins, low molecular weight glutenin subunits (LMW‐GS), and high molecular weight glutenin subunits (HMW‐GS) in sections of dough using antibody probes selective for each of the three classes of gluten polypeptides. Distinct differences in the distribution patterns of gliadins, LMW‐GS, and HMW‐GS were observed, which suggests that proteins have different roles in the structural organization of the gluten matrix. On the basis of the observed distribution of the proteins in dough, it is speculated that gliadins, which are randomly distributed as individual particles, fill space within the glutenin macropolymer; LMW‐GS, which are present as clusters, are speculated to form aggregated branch structures; and HMW‐GS, which are present as chains, are speculated to form a network from which the LMW‐GS branches are formed. Changes in the distribution of gliadins, LMW‐GS, and HMW‐GS in dough during mixing were also noted. Such an arrangement supports previous biochemical evidence which has established that gliadins, LMW‐GS, and HMW‐GS have specific roles in the structural organization of the glutenin macropolymer in doughs.
Image Analysis of Asian Noodle Appearance: Impact of Hexaploid Wheat with a Red Seed Coat
Authors: Hatcher D. W. , Symons S. J.
Published: June 2007

Fresh alkaline (kansui) and white salted noodles (WSN) prepared from patent and straight‐grade flour of the western Canadian wheat class Canadian Red Spring Wheat (CWRS) were visually characterizedby image analysis (IA) over a 24‐hr period. In both kansui noodles, the number of spots increased over time, while minimal change was detected in the WSN prepared from either flour. Maximum spot generation was observed in the straight‐grade kansui noodles, increasing from 53.1 spots per image at 1 hr to 76.2 by 7 hr before declining to 55.9 at 24 hr. Significant differences were detected in the number of detectable spots among the kansui, patent, and straight‐grade noodles over the initial 7 hr, but by 24 hr no discernible differences were observed. Fewest noodle spots were observed in the patent WSN (10.1 spots per image at 1 hr rising to 13.3 at 24 hr). Hence, straight‐grade flours yielded more spots than the matching patent flours, while WSN had consistently fewer spots relative to the kansui noodles at all time intervals. Minimal differences were detected in the average size of the spots due to noodle type or flour refinement, unlike the situation observed in white wheats investigated previously. Although discolored spots on the patent flour noodles were lighter than the straight‐grade counterparts, no difference was observed on the basis of noodle type.
Malted Sorghum as a Functional Ingredient in Composite Bread
Authors: Hugo L. F. , Rooney L. W. , Taylor J. R. N.
Published: June 2007

To alleviate the adverse effects (grittiness and high crumb firmness) caused by the inclusion of sorghum flour in composite breads, sorghum grain was malted with the aim of decreasing the gelatinization temperature and increasing the water‐holding capacity of sorghum flour. Four different heat treatments were investigated: drying the malt at high temperatures (50–150°C), stewing, steaming, and boiling before drying the malt at 80°C. Malting decreased the pasting temperature of sorghum to values approaching those of wheat flour, but the paste viscosity was very low. Increasing the malt drying temperature inactivated the amylases but gave malts of darker color and bitter taste. Stewing, steaming, and boiling the malt before drying almost completely inactivated the amylases and increased the enzyme‐susceptible starch content and the paste viscosity of malt flours. Bread made with boiled malt flour (30%) had an improved crumb structure, crumb softness, water‐holding capacity, and resistance to staling, as well as a fine malt flavor compared with the bread made with grain sorghum flour (30%). Consumers preferred the malted sorghum bread over the bread made with plain sorghum flour.
Rapid Size‐Exclusion Chromatography Analysis of Molecular Size Distribution for Wheat Endosperm Protein
Authors: Larroque O. R. , Bekes F.
Published: June 2007

A quick method for the separation of the main size classes of wheat endosperm proteins using size‐exclusion HPLC is presented. Separations achieved in a 10‐min run showed high correlation with the reference method of our laboratory (35‐min) using the same type of column. The clear separation obtained allows a quick analytical determination of important parameters such as the proportion of the main classes of wheat endosperm protein, the glutenin‐to‐gliadin ratio, and the percentage of unextractable (SDS‐soluble with sonication) polymeric protein, all of which have been closely correlated with breadmaking quality parameters. The improved method offers the advantages of better utilization of valuable resources such as HPLC equipment, quicker analysis of large sample sets, and collection of eluted fractions.
Optimum Steeping Process for Wet Milling of Sorghum
Authors: Wang F. C. , Chung D. S. , Seib P. A. , Kim Y. S.
Published: June 2007

Pioneer 8500, a red hard sorghum hybrid, was steeped batchwise using three steeping solutions at 50°C: SO2 solution; SO2 solution containing 1.25% (w/w) of a commercial multiple‐enzyme preparation (Novo SP249); and SO2 solution with the addition of 0.5% (w/w) lactic acid. Novo SP249 contained pectolytic, cellulolytic, hemicellulolytic, and proteolytic activities and small amounts of saccharolytic activities. Three SO2 concentrations (0.1, 0.2, and 0.3% w/v) prepared by dissolving sodium bisulfite in distilled water and three steeping times (24, 36, and 48 hr) were used. Incorporation of multiple enzymes into the SO2 resulted in an increase in starch yield with reduced protein content compared with the SO2 solution alone. The best wet‐milling performance for sorghum resulted from the SO2 solution containing 0.5% lactic acid; it produced the whitest starch with the highest yield and the lowest protein content. Both higher SO2 concentration of the steeping solution and longer steeping time led to higher starch yield, lower protein content in starch, and whiter starch. However, no significant differences in starch yield, protein content in starch, and starch color occurred between SO2 concentrations of 0.2 and 0.3% for all three steeping solutions. The optimum steeping process for wet milling of sorghum was using a 0.2% SO2 solution with 0.5% lactic acid for 36 hr at 50°C. Under these conditions, the starch yield, protein content in starch, and L value of starch color were 60.2% (db), 0.49% (db), and 92.7, respectively, which were not significantly different from the best values from the 48‐hr steeping using the solution with 0.3% SO2 and 0.5% lactic acid.
Moisture Redistribution and Phase Transitions During Bread Staling
Authors: Baik Moo‐Yeol , Chinachoti Pavinee
Published: June 2007

Standard white breads were stored with or without crust at 25°C in hermetic pouches. During two weeks of storage, the crumb moisture content and water activity (aw) decreased significantly when stored with crust. When stored without crust, moisture content and aw remained relatively unchanged. The causes of the initial firming of both breads over zero to seven days were not conclusive. But when stored beyond seven days, bread stored with crust was significantly firmer in texture and higher in amylopectin recrystallization than bread stored without crust. Moisture redistribution from crumb to crust played a significant role. This was accompanied by a decrease in freezable water in the bread crumb stored with crust. This loss in freezable water coincided with changes in the thermomechanical profile only in the case of sample stored with crust intact (and with a significant total and freezable water loss). Bread crumb stored without crust did not change in total and freezable water and showed less change in thermomechanical transitions. The transition occurring at ≈60°C (T2) correlated with amylopectin recrystallization but it could also have been caused by moisture loss during the analysis. Moisture migration from crumb to crust greatly reduced the total and freezable water in the crumb region, resulting in a significant reduction in the magnitude of the mechanical transition at ≈0°C (T1) as well as an increase in the storage modulus.
Accessibility of Amino Groups in Gluten Proteins Studied by a Combination of Chemical Labeling and Immunochemical Detection
Authors: Scardone Daniela , Forlani Fabio , Cerletti Paolo
Published: June 2007

The accessibility of primary amino groups to an external probe in durum wheat gluten proteins in the flour itself, and after the extraction and separation of gluten proteins, was studied by labeling the free amino groups with the hemisuccinate of 2‐(2,4‐dichlorophenyl)‐3‐(1H‐1,2,4‐triazol‐1‐yl) propanol (FF18) and evidencing the label immunochemically. Within the flour, the amino groups were less available to the probe than after extraction, and gliadins were less accessible than glutenins, differences that decrease after solubilization and separation of the proteins. Data are discussed in relation to the structural organization of proteins within gluten.
Characterization of the 1B‐Type ω‐Gliadins from Triticum aestivum Cultivar Butte
Authors: DuPont Frances M. , Vensel William H. , Chan Ronald , Kasarda Donald D.
Published: June 2007

ω‐Gliadins were purified from wheat (Triticum aestivum L. ‘Butte’) flour and characterized. Although reversed‐phase HPLC (RP‐HPLC) separated the 1B‐encoded ω‐gliadins into two fractions, 1B1 and 1B2, these fractions had nearly identical amino acid compositions, three similar protein bands in SDS‐PAGE, 10 similar spots in two‐dimensional PAGE, and two similar N‐terminal amino acid sequences. The main components had a range in mass of 48,900–51,500 when estimated by mass spectrometry, significantly less than the mass estimated by SDS‐PAGE. The 1B fractions were digested with thermolysin, the peptides were separated by RP‐HPLC, the peptide mass was determined, and nine peptides from each fraction were sequenced with nearly identical results for the 1B1 and 1B2 digests. A possible consensus sequence of the 1B‐encoded ω‐gliadin internal repeat was QQQXP, where X was F, I, or L in descending order of occurrence. The 1D‐encoded ω‐gliadins were purified by RP‐HPLC as a single fraction that had one band in SDS‐PAGE, two spots in two‐dimensional PAGE, two components with mass of 41,923 and 42,770 detected by mass spectrometry, and two N‐terminal sequences. Circular dichroism (CD) spectra for the 1B and 1D ω‐gliadins were similar and were suggestive of mainly flexible random structure with a significant amount of the left‐handed polyproline II helical conformation in the 1D components.
Improved Method for Isolating and Quantitating α‐Amino Nitrogen as Nonprotein, True Protein, Salt‐Soluble Proteins, Zeins, and True Glutelins in Maize Endosperm
Authors: Landry J. , Delhaye S. , Damerval C.
Published: June 2007

The conventional Landry‐Moureaux method for selective extraction of maize proteins was modified by reducing the contact time of meal with extractants and by removing 55% 2‐propanol as extractant. The new procedure, coupled with a method for quantitating protein at microgram level, was used for assessing the nitrogen distribution of four soluble protein fractions present in 100‐mg samples of endosperm originating from six maize inbreds and opaque‐2 versions. Proteins extracted with 55% 2‐propanol plus reductant were made up of α‐, β‐, γ‐, and δ‐zeins. Proteins extracted subsequently with salt plus reductant were minor and poor in lysine (1 mol%).They were associated with zeins. Comparison of present data with those available in the literature showed a close similarity for a given genotype between the percentage of total α‐amino nitrogen extracted by 2‐propanol plus reductant than by salt plus reductant under conditions of the modified procedure and that of total Kjeldhal nitrogen extracted by 2‐propanol with and without reductant, and by salt plus reductant, using the conventional procedure. A simplified protocol was described and tested for isolating and quantitating α‐amino nitrogen as nonprotein, true protein, salt‐soluble proteins, zeins, and true glutelins in any sample of maize endosperm.
Influence of Added Starch on Mixing of Dough Made with Three Wheat Flours Differing in High Molecular Weight Subunit Composition: Rheological Behavior
Authors: Larsson H. , Eliasson A.‐C. , Johansson E. , Svensson G.
Published: June 2007

The effect of mixing time (6 and 20 min) and starch content were studied on doughs prepared with three wheat flours differing in high molecular weight subunit composition. Rheological measurements were performed in dynamic oscillation: frequency and strain sweeps, stress relaxation, and in large deformation viscosity measurements. The flours were diluted with starch to cover flour protein contents of 10–15%. Water was added to keep the starch‐water ratio constant when doughs were prepared with different protein contents. By increasing the starch content of the doughs, the rheological properties approached those of a starch‐water mixture prepared with the same starch‐water ratio as in the dough. The effect of the starch granules was reinforced by prolonged mixing. This may explain the higher values of the storage modulus and relaxation times observed after 20 min of mixing. Qualities related to gluten properties, appeared more clearly in large deformation viscosity measurements.
Quick Fiber Process: Effect of Mash Temperature, Dry Solids, and Residual Germ on Fiber Yield and Purity
Authors: Wahjudi J. , Xu Li , Wang Ping , Singh V. , Buriak P. , Rausch K. D. , McAloo A. J. , Tumbleson M. E. , Eckhoff S. R.
Published: June 2007

Preliminary calculations showed that recovery of fiber before fermentation in the dry grind ethanol facilities known as the Quick Fiber process increases fermenter capacity and reduces ethanol production cost by as much as 4 ¢/gal. The objective of the current research was to evaluate the effect of mash temperature, dry solids, and residual germ on fiber yield and purity when using the quick fiber process. Fiber was recovered by flotation and skimming, while maintaining a specified temperature, dry solids, and residual germ in the mash. Varying temperature and dry solids in the mash resulted in a statistically significant effect on the fiber yield, neutral detergent fiber (NDF) content, and weight of NDF/100 g of dry corn. Varying residual germ in the mash resulted in statistically significant differences for NDF through dilution and the weight of NDF/100 g of dry corn. The highest fiber yield was 10.9% at 45°C, 23% dry solids, and 15% residual germ; the highest NDF was 50.9% at 30°C, 21% dry solids, and 0% residual germ. The highest weight of NDF/100 g of dry corn was observed at 45°C, 23% dry solids, and 0% residual germ.
Production and Nutritional Evaluation of Liquefied Weaning Foods from Malted Sorghum, Quality Protein Maize, and Other Cereals
Authors: Delgado M. L. Barragán , Saldivar S. O. Serna
Published: June 2007

Different concentrations of sorghum diastatic malt (SDM) were added to pregelatinized pastes from regular maize flour with the aim of hydrolyzing the starch to produce liquefied foods with 15% solids. Viscosities of the blends decreased as the concentration of SDM increased. Addition of 6.66% SDM based on total amount of solids reduced viscosity by ≈50% when compared with a food that did not contain any SDM. Addition of 33.3 or 46.6% SDM reduced viscosity by ≈70 or 75%, respectively. Most of the reduction in viscosity occurred within 1–3 min of incubation with warm water. Weanling rats were fed a combination 33.3% SDM and 66.6% of either quality protein maize (QPM), regular maize (RMZ) or decorticated pearl millet (DPM) to estimate protein efficiency ratios (PER), protein digestibility, biological value (BV), and net protein utilization (NPU). Rat growth was positively correlated with dietary lysine content and essential amino acid (EAA) scores; therefore, animals fed QPM weanling food had significantly higher (P < 0.05) protein digestibility corrected EAA scores, PER, BV, and NPU than counterparts fed diets based on RMZ or DPM. This demonstrates that it is feasible to produce nutritious liquefied weaning foods blending 33.3% SDM with 66.6% QPM using simple processing techniques.
Effect of Various Acids and Sulfites in Steep Solution on Yields and Composition of Corn Fiber and Corn Fiber Oil
Authors: Singh Vijay , Moreau Robert A. , Haken Armgard E. , Hicks Kevin B. , Eckhoff Steven R.
Published: June 2007

The addition of six acids (organic and inorganic) and four sulfite compounds (including gaseous SO2) during the conventional corn wet‐milling steeping process of two yellow dent corn hybrids were evaluated for the effect on corn fiber yield, corn fiber oil yield, and the composition of three phytosterol compounds (ferulate phytosterol esters [FPE], free phytosterols [St], and phytosterol fatty acyl esters [St:E]) in the corn fiber oil. No significant effect of different sulfite compounds and acids were observed on corn fiber yields. However, a significant effect was observed on corn fiber oil yield and the composition of corn fiber oil for phytosterol compounds. Three of the sulfite compounds (including gaseous SO2) caused very little effect on the levels of phytosterol compounds compared with the control sample (corn steeped with sodium metabisulfite and lactic acid). However, for one hybrid, ammonium sulfite gave a significantly higher yield of FPE and St:E and had no effect on the yield of St. For the other hybrid, it gave a significantly higher yield of FPE and had no effect on the yield of St and St:E compared with the control sample. This indicates that the effect of these sulfite compounds on yields of these phytosterol compounds in corn fiber oil is probably hybrid‐dependent. No significant effect of acids was observed on corn fiber yields, but significant effects were observed on corn fiber oil yields and yields of phytosterol compounds in the corn fiber oil. The effect also seems to be hybrid‐dependent because different acids affected the two hybrids differently. Overall, it seems that weak acids have a positive effect on increasing the individual phytosterol compounds in the corn fiber. When comparing the effect of experimental acids and sulfites on the two hybrids, acids have a more positive effect than sulfites in increasing the yield of phytosterol compounds in corn fiber oil.
Adsorption Studies of Interaction Between Water‐Extractable Nonstarch Polysaccharides and Prolamins in Cereals
Authors: Elofsson U. , Eliasson A‐C. , Wahlgren M. , Loosveld A.‐M. A. , Courtin C. M. , Delcour J. A.
Published: June 2007

Adsorption of cereal storage protein and nonstarch polysaccharides onto methylated silica surfaces, as measured by ellipsometry, was used to study possible interactions between those components. All fractions, rye secalin, wheat gliadin, rye arabinoxylan, and wheat arabinogalactan peptide, were surface‐active to some degree. Sequential adsorption of rye arabinoxylan and wheat arabinogalactan peptide on top of gliadin and secalin, respectively, indicated that an interaction occurred. As ionic strength and pH influenced both the adsorption and the interaction of the components studied, these phenomena are believed to be of electrostatic nature.