bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structure and Functionality of Barley Starches
Authors: Czuchajowska Z. , Klamczynski A. , Paszczynska B. , Baik B.‐K. 
Published: June 2007

ABSTRACTAmylose contents of prime starches from nonwaxy and high‐amylose barley, determined by colorimetric method, were 24.6 and 48.7%, respectively, whereas waxy starch contained only a trace (0.04%) of amylose. There was little difference in isoamylase‐debranched amylopectin between nonwaxy and high‐amylose barley, whereas amylopectin from waxy barley had a significantly higher percentage of fraction with degree of polymerization < 15 (45%). The X‐ray diffraction pattern of waxy starch differed from nonwaxy and high‐amylose starches. Waxy starch had sharper peaks at 0.58, 0.51, 0.49, and 0.38 nm than nonwaxy and high‐amylose starches. The d‐spacing at 0.44 nm, characterizing the amylose‐lipids complex, was most evident for high‐amylose starch and was not observed in waxy starch. Differential scanning calorimetry (DSC) thermograms of prime starch from nonwaxy and high‐amylose barley exhibited two prominent transition peaks: the first was >60°C and corresponded to starch gelatinization; the second was >100°C and corresponded to the amylose‐lipid complex. Starch from waxy barley had only one endothermic gelatinization peak of amylopectin with an enthalpy value of 16.0 J/g. The retrogradation of gelatinized starch of three types of barley stored at 4°C showed that amylopectin recrystallization rates of nonwaxy and high‐amylose barley were comparable when recrystallization enthalpy was calculated based on the percentage of amylopectin. No amylopectin recrystallization peak was observed in waxy barley. Storage time had a strong influence on recrystallization of amylopectin. The enthalpy value for nonwaxy barley increased from 1.93 J/g after 24 hr of storage to 3.74 J/g after 120 hr. When gel was rescanned every 24 hr, a significant decrease in enthalpy was recorded. A highly statistically significant correlation (r = 0.991) between DSC values of retrograded starch of nonwaxy barley and gel hardness was obtained. The correlation between starch enthalpy value and gel hardness of starch concentrate indicates that gel texture is due mainly to its starch structure and functionality. The relationship between the properties of starch and starch concentrate may favor the application of barley starch concentrate without the necessity of using the wet fractionation process.
Effects of Lysine on Growth of Tilapia Fed Diets Rich in Corn Gluten Meal
Authors: Wu Y. Victor , Rosati Ronald R. , Brown Paul B. 
Published: June 2007

ABSTRACTTilapia is a warmwater fish with mild flavor. Nearly 8.6 million kg are produced domestically, and ≈22.7 million kg are imported. Corn gluten meal (60% protein fraction) is a product obtained from wet‐milling of corn. Diets (36% protein) containing 36–44% corn gluten meal with different levels of lysine and fish meal were formulated and fed to tilapia in aquaria for 12 weeks. Weight gain (WG) of tilapia fed diets containing the highest level of lysine (7.4% protein) with 4% fish meal was equal to that of fish fed a commercial control diet. Diets with lower lysine resulted in lower WG. The feed conversion ratio (FCR) and protein efficiency ratio (PER) of tilapia fed experimental diets containing adequate levels of essential amino acids and fish meal were the same as for fish fed the commercial control diet (also containing fish meal). Fish fed diets containing lower lysine levels had less favorable FCR and PER. This study shows that corn gluten meal is utilized at high levels in tilapia diets, particularly if essential amino acids are provided in adequate amounts.
Comparison of Water Absorption Patterns in Two Barley Cultivars, Using Magnetic Resonance Imaging
Authors: McEntyre E. , Ruan R. , Fulcher R. G. 
Published: June 2007

ABSTRACTTwo barley cultivars, Excel and Prisma (six‐row and two‐row types, respectively), were obtained from the 1993 harvest at Crookston, MN. Magnetic resonance imaging (MRI) was used to follow water imbibition in single, large seeds of Excel and Prisma barley. A comparison of moisture distribution on longitudinal sections of Prisma and Excel barley during early hours of steeping was then made. MRI analysis revealed that the majority of water initially entered the kernel through the kernel surfaces and into the endosperm tissues. Water was observed under the surface of the hull tissues and appeared to be migrating into the aleurone and endosperm tissues. Then water was detected moving from the embryo to the scutellum and then into the crushed cell layers. Aleurone and embryo tissue showed more rapid water uptake and distribution than did scutellar tissue. Some transient water distribution was observed in the scutellum, ventral furrow, and vascular tissues. This indicates that the hydration of surface tissues and crushed cell layers may be significant during the early hours of steeping. During the late hours of steeping, the crushed cell and endosperm cavity region appears to become remarkably active in water transport. Water was distributed throughout the endosperm tissue of the Prisma cultivar more efficiently than in that of the Excel cultivar, although Excel absorbed more water initially.
Volatiles in Selected Commercial Breads
Authors: Seitz L. M. , Chung O. K. , Rengarajan R. 
Published: June 2007

ABSTRACTSelected types of commercial breads obtained from local markets, including white sandwich, Irish oatmeal, soft rye, hearty rye, sour dough, home‐like white, and onion‐basil, were analyzed for volatiles. Using a purge and trap instrument, volatiles were purged directly from fresh crumb and crust samples of each bread type, collected on a trap (Tenax‐TA), and transferred to a gas chromatograph. Separated components were detected and identified using mass and infrared spectroscopic detectors. Many components were present in all of the bread samples, with relative amounts varying among bread types and crust and crumb samples of a given bread type. Alcohols were generally the most abundant, followed in approximate order by aldehydes, esters, ketones, acids, various aromatics, terpenes, and hydrocarbons. Flavor additives, such as limonene, carvone, and other related compounds, were found mostly in rye and onion‐basil breads. Composition of volatiles from sour dough bread differed greatly from the other breads, especially in increased levels of aldehydes, acids, and certain esters. Unsaturated aldehydes, such as 2‐hexenal and 2‐heptenal, were most abundant in sour dough bread.
Polymorphism of Aspartic Proteinases in Resting and Germinating Barley Seeds
Authors: Zhang Ningyan , Jones Berne L. 
Published: June 2007

ABSTRACTBoth resting and germinated barley seeds (Hordeum vulgare L. ‘Morex’) contain aspartic endopeptidase activities, and the activities increase during germination. We have extracted and partially purified aspartic endopeptidases from both resting seeds and green malt (four‐day germinated barley). Six aspartic proteinase activities were found in resting barley seeds while only four activities were detected in green malt. All of the aspartic proteinases had similar pH activity optima (pH 3.5–4.5) and pI values (≈4.5). The purified green malt aspartic proteinases selectively digested a group of barley seed proteins, postulated to serve as defensive proteins, that are coded by the amylase‐trypsin inhibitor super gene family. The aspartic proteinases that bound to a pepstatin A affinity column at pH 4.5 cross‐reacted with antiserum raised against aspartic proteinases purified from barley seed. However, those that did not bind the affinity column also did not cross‐react with the antiserum, indicating that there are two distinct groups of aspartic proteases in germinating barley.
Effect of Dough Processing Conditions and DATEM on Norwegian Hearth Bread Prepared from Frozen Dough
Authors: Sahlstr⊘m S. , Nielsen A. O. , Færgestad E. M. , Lea P. , Park W. J. , Ellekjær M. R. 
Published: June 2007

ABSTRACTThe objective of this study was to examine treatments that directly influence Norwegian lean doughs destined to be frozen. Therefore a strip‐block experimental design with four dough treatment factors (wheat flour blend, diacetyl tartaric acid esters of monoglycerides [DATEM], water absorption, and dough temperature) and two storage factors (frozen storage time and thawing time) was used. Four levels were selected for frozen storage time and two levels were selected for the remaining factors. After frozen storage (2–70 days), the doughs were thawed and baked. Principal component analysis showed that to obtain a high loaf volume and bread score after freezing, a high dough temperature after mixing (27°C) was essential. The highest form ratio (height/width) level was obtained after 28 days of frozen storage and with a short thawing time (6 hr). Analysis of variance (ANOVA) of dough treatments showed that an increase in dough temperature from 20 to 27°C after mixing resulted in a significant increase in loaf volume (1,653 to 2,264 mL), form ratio (0.64 to 0.69), and bread score (1.7 to 3.2), and a reduction in loaf weight (518.4 to 512.5 g) and crumb score (7.9 to 5.9, i.e., a more open bread crumb). Also, the addition of DATEM significantly increased loaf volume (1,835 to 2,081 mL), form ratio (0.64 to 0.69), and bread score (2.2 to 2.6). Frozen dough storage time significantly affected loaf volume, loaf weight, bread score, and crumb score. Increasing thawing time from 6 to 10 hr significantly increased loaf volume (1,855 to 2,121 mL), and reduced the form ratio (0.69 to 0.63) and loaf weight (516.8 to 511.4 g). ANOVA of the interaction between dough treatment and frozen storage time showed that decreasing water absorption significantly increased the loaf volume.
Evaluation of Starch Properties of Wheats Used for Chinese Yellow‐Alkaline Noodles in Japan
Authors: Akashi Hajime , Takahashi Miwa , Endo Shigeru 
Published: June 2007

ABSTRACTThe objective of the present research was to assess the functional properties of the starches isolated from Australian prime hard wheat (PH) and hard red winter wheat (HRW) in the United States. These wheats are favorably used in Japan for the production of Chinese yellow‐alkaline noodles (YAN). Starches isolated from PH showed higher amylose content than those of noodle wheat but lower than bread wheat. Analysis of swelling power showed that PH starch had lower values than noodle wheat starches but higher values than bread wheat starches. By contrast, HRW starch showed relatively higher amylose content and lower swelling power. There were large differences in the starch pasting properties between PH and HRW. High‐performance size‐exclusion chromatography studies on the components leached from the starch (80°C, 20 min) showed that PH starch had a somewhat characteristic leaching profile. Its peak ratio of high molecular weight region to low molecular weight region was greater than that of HRW starch. PH starch also characterized by having lower endothermal enthalpy (ΔH) in amylose‐lipid transition. The eating quality assessment for YAN revealed that PH had more elastic texture than HRW. Additional reconstitution studies showed that these quality differences could be attributable to its starch properties.
Measurement of the Time‐Dependent Appearance of Discolored Spots in Alkaline Noodles by Image Analysis
Authors: Hatcher D. W. , Symons S. J. , Kruger J. E. 
Published: June 2007

ABSTRACTFresh alkaline noodles prepared from patent flours of the Canadian wheat class Canadian Prairie Spring White (CPSW) AC Karma and AC Vista were characterized by image analysis to numerically evaluate the time‐dependent formation of dark areas (spots) on the noodle surface. The system was able to rapidly detect, measure, and characterize such undesirable discolorations, which commonly form on the surface of raw noodles with time. Variations in minimum spot detection size (0.050–0.250 mm2), in combination with a darkness threshold setting (Δ grey scale units of 2, 5, and 10) were investigated. A linear increase in the number of spots was observed over time for both cultivars with nine combinations of size and darkness. The total number of discolored spots measured was dependent on both detection size and sensitivity (threshold setting). Significant differences (P < 0.05) in the number of darkened spots were detected between the two cultivars only after 24 hr. Similarly, significant differences (P < 0.05) in size of the spots between the two cultivars was observed at 24 hr. Darkening was most rapid within the first hour for both cultivars, followed by a period of stability before a significant (P < 0.05) further increase by 24 hr. Characterization of the darkness distribution indicated significantly different distribution profiles for the two cultivars examined, which was consistent with their noodle brightness (L*) values.
Initial Heating Temperature and Native Lipid Affects Ordering of Amylose During Cooling of High‐Amylose Starches
Authors: Boltz Kathryn W. , Thompson Donald B. 
Published: June 2007

ABSTRACTFormation of ordered structures from disordered amylose is practically important. The thermal behavior of high‐amylose maize starches was studied during cooling, following heating, and during subsequent reheating. Four commercial high‐amylose genotype maize starches with varying amylose contents (ae du, ae su2, and ae [nominally both 50 and 70% amylose]) were heated to either 120, 140, 160, or 180°C, cooled to 5°C, and reheated to 180°C in a differential scanning calorimeter. Each starch was studied with its native lipid, as well as in reduced‐lipid and lipid‐free form. On cooling of lipid‐containing starches, two distinct exotherms were observed and attributed to amylose‐lipid complex formation and to amylose chain association. A distinct exotherm at ≈75°C was attributed to amylose‐lipid complex formation. The exotherm attributed to amylose chain association on cooling varied according to the initial heat treatment, lipid level, and starch type. Starches with higher amylose contents showed larger exotherms on cooling. For initial heat treatments to 120 or 140°C, a broad exotherm beginning at ≈95°C was observed on cooling. In contrast, for initial heat treatments to 160 and 180°C, a sharper exotherm with a peak temperature below ≈55°C was observed. Upon reheating, samples that had been initially heated to 120 or 140°C showed a peak at >140°C that was attributed to the melting of ordered amylose. Starches initially heated to 160 or 180°C did not show this peak. This work illustrates that initial heating temperature, as well as lipid content and amylose content, all affect amylose chain association during cooling. Thus, this work suggests strategies for controlling ordering of amylose during processing.
Effect of Adding Exogenous Oxidative Enzymes on the Activity of Three Endogenous Oxidoreductases During Mixing of Wheat Flour Dough
Authors: Rakotozafy Lalatiana , Mackova Bozena , Delcros Jean‐François , Boussard Aline , Davidou Sylvie , Potus Jacques , Nicolas Jacques 
Published: June 2007

ABSTRACTThe behavior of different exogenous enzymes (soybean lipoxygenase [SLOX], horseradish peroxidase [HPOD], catalase from bovine liver [BCAT], and glucose oxidase [GOX] from Aspergillus niger) added to dough was studied during mixing. The effect of adding these exogenous oxidoreductases on the activity of three oxidative enzymes present in wheat flour (lipoxygenase [WLOX], peroxidase [WPOD], and catalase [WCAT]) was examined. Proper assay conditions were established to differentiate between added WLOX, WPOD, and WCAT and the corresponding activities present in wheat flour. For doughs with added SLOX, an immediate loss of extractable SLOX (≈40%) was observed which remained constant during further mixing. When compared with the control dough, addition of SLOX decreased the losses in WLOX and WCAT activities, whereas WPOD activity was unaffected. With doughs supplemented by HPOD, an immediate loss of 20% in the HPOD activity was observed which did not change after 20 min of mixing. Compared with control dough, addition of HPOD did not affect the behavior of WLOX and WPOD, whereas a slight decrease in the WCAT losses was observed. Addition of BCAT to the dough did not change the behavior of WLOX and WPOD, whereas the losses in WCAT were less rapid. Half of the extractable activity of BCAT was lost at the beginning of mixing with no change during further mixing. For doughs supplemented with GOX, 25% of the GOX activity was lost in the first 5 min of mixing and an additional loss of 20% was observed after 20 min of mixing. Compared with dough without GOX, addition of GOX decreased the losses in WLOX, whereas losses in WCAT and WPOD increased. Glucose and ferulic acid were also added to doughs supplemented with GOX. Added glucose decreased the losses in GOX and WLOX and did not change the behavior of WPOD and WCAT during mixing. Addition of ferulic acid promoted a slight increase of the losses in WLOX and WCAT and almost no change for GOX and WPOD.
Effects of Feed Rate and Screw Speed on Operating Characteristics and Extrudate Properties During Single‐Screw Extrusion Cooking of Rice Flour
Authors: Yeh An‐I , Jaw Yih‐Mon 
Published: June 2007

ABSTRACTRice flour (37% moisture content) was used to examine the effects of feed rate and screw speed on the specific energy input during single‐screw extrusion cooking. Torque, raised by decreasing screw speed or increasing feed rate, was found to be a power law function of the ratio of feed rate to screw speed (Fr/Ss) with r2 > 0.94. Specific mechanical energy (SME) calculated from torque also was a power law function of Fr/Ss with r2 >0.84 and negative power law indices. The SME obtained was in the 225–481 kJ/kg range. Thus the extruder can be considered low shear. Increasing SME raised the die temperature and decreased both intrinsic viscosity and water absorption index (WAI). The degree of gelatinization and intrinsic viscosity of extrudates also were power law functions of Fr/Ss. The intrinsic viscosity correlated well with the degree of gelatinization, WAI, and cooking loss, and appeared to be a good index of the extrudate properties. Different screw profiles also affect torque measurement.
Isolation and Identification of a Wheat Flour Compound Causing Sticky Dough
Authors: Huang W. N. , Hoseney R. C. 
Published: June 2007

ABSTRACTFractionation and reconstitution studies of a flour from 1B/1R wheat showed that the factor causing sticky dough was water soluble. In addition, these studies showed that enzymes and lipids in the flour were not responsible for producing sticky dough. Dialysis experiments showed that the active component was nondialyzable. Gel‐filtration chromatography of the retentate fraction showed that the substance causing sticky dough contained both a carbohydrate and a UV‐absorbing material. Treatment of the active fraction with base caused the fraction to lose its ability to cause stickiness. The UV‐absorbing material and the carbohydrate fraction had to be covalently linked for the compound to be active. Gas chromatography‐mass spectrometry and HPLC analysis showed that the UV‐absorbing moiety was predominantly trans‐ferulic acid, and the carbohydrate part was a glucose polymer. The glucose polymer was not degraded by α‐amylase but was degraded by lichenase, suggesting that the glucose polymer was a mixed‐linkage β‐glucan.
Physicochemical Properties of Flours that Relate to Sorghum Couscous Quality
Authors: Aboubacar Adam , Hamaker Bruce R. 
Published: June 2007

ABSTRACTFlours from eight sorghum cultivars were evaluated for their couscous‐making ability with the objective of finding predictive relationships between flour physicochemical properties and couscous quality. Chemical composition, physical characteristics, and pasting and gelatinization properties of the flours were determined. A laboratory procedure was used to prepare couscous. Couscous properties were evaluated and compared to a laboratory‐prepared and a commercial durum wheat couscous. Hard grain produced flours containing a high proportion of coarse particles with low ash and high damaged starch content and yielded a higher proportion of desirable sorghum couscous granules. A variety of colors ranging from brown to yellow were obtained when flours were processed into couscous. Cooked sorghum couscous stickiness was positively correlated (r = 0.89, P < 0.01) with the amount of damaged starch in flour. Cooked couscous hardness correlated positively (r = 0.79, P < 0.05) with apparent amylose content of flour and correlated negatively (r = ‐0.75, P < 0.05) with flour peak viscosity. Durum wheat couscous was lighter and had more yellow color than sorghum couscous. Sorghum couscous was stickier and harder than durum wheat couscous. Addition of 2% oil to the cooking water considerably improved the texture of some sorghum couscous to a level comparable to that of durum wheat couscous.
Starch and Protein Quality Requirements of Japanese Alkaline Noodles (Ramen)
Authors: Crosbie G. B. , Ross A. S. , Moro T. , Chiu P. C. 
Published: June 2007

ABSTRACTStudies on samples of 20 hard‐grained wheat cultivars and a commercial flour that varied in starch and protein quality showed that both characteristics influenced the texture of Japanese alkaline noodles (ramen). Flour swelling volume (FSV) and flour pasting characteristics (peak viscosity and breakdown) determined with a Rapid‐Visco Analyser (RVA) assessed independently of α‐amylase effects, were negatively correlated with total texture score. Protein quality, as indicated by farinograph stability, was positively correlated with total texture score. RVA pasting characteristics were substantially affected by small levels of α‐amylase, and inactivation by means of 1 mM AgNO3 was a critical requirement in characterizing the quality of the starch component of flour.
Paste Properties of Modified Starches from Partial Waxy Wheats
Authors: Reddy Indira , Seib Paul A. 
Published: June 2007

ABSTRACTProperties of modified starches from partial waxy wheats have not been examined. Protease digestion of cracked kernels of three hard winter wheats varying in amylose content led to 82–85% recovery of starch, whereas kneading of the flour‐water doughs gave 75–83% recovery. All starches had a protein content of <0.3% and ash content of <0.01%. Granule size distributions showed that starch from Ike kernels contained 86% A‐type granules with a peak size of ≈18μm, and Karl‐92 starch contained 77% A‐type granules with a peak size of ≈16μm. The A‐type granules (82%) from Rio Blanco starch were intermediate in size. The amylose content of Karl‐92 starch, determined by concanavalin‐A precipitation of amylpectin, was 28%, which was 17% higher than that of Ike starch (23%). The amylose content of Rio Blanco starch was 26%. The lipid content of Karl‐92 starch, determined as fatty acid methyl esters, also was 18% higher than that of Ike starch (601 vs. 488 mg/100 g of starch, respectively). Wheat starches were modified with hydroxypropyl (HP) groups to low (1.5–2.5%) and medium (≈4.0%) levels, and the HP starches were cross‐linked with phosphoryl chloride at levels of 0.003–0.075%. Pasting curves (amylograms) showed that Ike starch substituted with a low level of HP and optimally cross‐linked with 0.025% phosphoryl chloride (starch basis) had a greater paste consistency than low HP cross‐linked Karl‐92, and Rio Blanco starches. At 4% HP and optimum cross‐linking (0.003% phosphoryl chloride), the paste consistencies of the modified starches were nearly the same. The clarity of unmodified Ike starch paste was higher than that of Karl‐92 or Rio Blanco starch pastes, and the clarity of all three pastes decreased as cross‐linking was increased. Unmodified Ike starch formed a stronger gel than unmodified Karl‐92 and Rio Blanco starches, but gel properties largely converged as the starches were modified.