bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mixograph Absorption Determination by Response Surface Methodology
Authors: Ingelin M. E. , Lukow O. M. 
Published: June 2007

ABSTRACTThe advantages of using the mixograph to determine dough mixing properties include minimal flour requirements (2–35 g) and an efficient mixing process that rapidly resolves mixing peaks. A disadvantage to using this instrument is that it lacks an objective absorption measurement. This article describes an analysis system, RsMix, that objectively determines water absorption and statistically evaluates (R2 and probability values) this measurement. The RsMix system also exports files that produce response surface plots. These plots illustrate the response of the dough to different combinations of mixing time and absorption. Each data set analyzed by the RsMix system was composed of an absorption series run at 2% absorption increments. The RsMix system attempts to maximize power input over data collected over absorption and time ranges. These data can be input manually or automatically acquired from MixSmart data files. To measure the precision of the RsMix system, a replicated absorption series composed of four to six different amounts of added water was analyzed. Depending on the mixer and formulation used, calculated standard deviations for optimum absorptions ranged from 0.8 to 2.0%. A regression comparing flour protein content to 2‐g mixograph absorption had r2 = 0.80. A similar regression comparing 2‐g mixograph to 50‐g farinograph absorption had r2 = 0.81. Mixograph parameters could also account for 90% or more of the variation in bake absorption, bread volume, and total bread scores.
Rheological Method for Evaluating Endoproteolytic Enzyme Activity
Authors: Bleukx Wouter , van Oort Maarten G. , Delcour Jan A. 
Published: June 2007

ABSTRACTA rheological method for evaluating endoproteolytic enzyme activity was developed. The decrease in viscosity as a function of time of dispersion of commercially available modified wheat gluten protein in water (15%, w/w) was measured with a rapid visco analyzer (RVA). Measurement of the RVA viscosity signal at a chosen temperature was continuous and reproducible. As described, the method also can be used to determine the temperature optima of endoproteolytic enzymes at pH values exceeding 5.5 and for partial pH‐activity profiles at different temperatures. The method is simple, reproducible, and sensitive and has obvious advantages over more labor‐intensive methods in which changes in the rheological properties (elongational viscosity, stretch ratio) of a gluten‐starch dough are evaluated as a function of time.
Effects of Low Molecular Weight Carbohydrates on Farinograph Characteristics and Staling Endotherms of Wheat Flour‐Water Doughs
Authors: Duedahl‐Olesen L. , Zimmermann W. , Delcour J. A. 
Published: June 2007

ABSTRACTGlucose, maltose, maltotriose, maltotetraose, α‐ and γ‐cyclodextrins, and maltodextrins from potato starch (average degree of polymerization [DP] of 17) and maize starch (average DP of 20) were added to wheat flour‐water doughs at levels of 1.0 and 3.0% (based on dry flour weight). Additions of 3.0% (w/w) α‐ and γ‐cyclodextrins increased the 500 farinograph unit (FU) consistency by 174 and 193 FU, respectively, while the same levels of potato and maize starch dextrins increased the consistency by 32 and 21 FU, respectively. Expressed in an alternative way, the water absorption corresponding to 500 FU consistency was increased by 4.2 and 4.6% after addition of 3.0% (w/w) α‐ and γ‐cyclodextrins, respectively. Differential scanning calorimetry was used to evaluate the direct effects of addition of low molecular weight carbohydrates on amylopectin recrystallization in baked flour‐water doughs. A significant reduction in amylopectin recrystallization was found after the addition of 3.0% (w/w) γ‐cyclodextrin after seven days of storage of the baked wheat flour‐water dough.
Use of the Rubber Elasticity Theory to Characterize the Viscoelastic Properties of Wheat Flour Doughs
Authors: Leonard A‐L. , Cisneros F. , Kokini J. L. 
Published: June 2007

ABSTRACTThe viscoelastic properties of durum wheat flour doughs were measured using the extensigraph in uniaxial extension and the Rheometrics mechanical spectrometer in oscillatory shear. The research examined the effect of increasing density of cross‐links on rubber elasticity in these systems. The stress‐strain behavior of durum wheat flour dough was not well simulated by Mooney‐Rivlin type nonlinear elasticity. Addition of increasing amounts of iodate made the dough show appreciable strain thickening behavior, approximating the behavior of natural rubbers The estimated apparent molecular weight between cross‐links ranged from 10,500 to 16,000, much larger than that of rubbers, for which values are in the range of 500–1,000. When the Mooney‐Rivlin equation was tested, it appeared to approximate only moderately well the extensional behavior of iodate‐added wheat flour doughs at finite but low extensions, where the finite extensibility of chains is not a factor. It is hypothesized that the cross‐linked network is highly diluted with hydrogen and hydrophobic bonds that limit the applicability of rubberlike elasticity theories. Increasing the cross‐linked density using iodic acid developed matrices that moved the behavior of durum flour doughs closer to Mooney‐Rivlin behavior.
Starch‐Lipid Interactions in Common, Waxy, ae du, and ae su2 Maize Starches Examined by Differential Scanning Calorimetry
Authors: Villwock V. Kurtis , Eliasson Ann‐Charlotte , Silverio José , BeMiller James N. 
Published: June 2007

ABSTRACTFour maize genotypes (common, waxy, ae du, and ae su2) were examined by differential scanning calorimetry (DSC) in the presence of four surfactants (sodium dodecyl sulfate [SDS], dodecyltrimethylammonium bromide [DOTAB], sodium hexadecyl sulfate [SHS], 1‐monolauroyl‐rac‐glycerol [ML]) to characterize the starch‐lipid complexes produced and provide evidence of differences in starch structure. The ionic surfactants with a C12 hydrocarbon tail reduced the gelatinization onset temperature, a phenomenon that does not occur typically with neutral surfactants or with surfactants with longer hydrocarbon tails. Subtracting the DSC curves, the exotherm we suspected was caused by starch‐lipid complexation, which occurs concomitantly with the gelatinization endotherm, was identified and provided evidence of the existence of amylopectin‐lipid interactions. Apparent starch amylose content correlated well with enthalpies of amylose‐lipid complexes. Complexes formed from DOTAB produced DSC endotherms that were broad and shallow and that shifted to lower temperatures as the DOTAB concentration increased. This was in contrast to other surfactants that normally produce amylose‐lipid complex endotherms at temperatures independent of surfactant concentration.
Evaluation of a Two‐Step Baking Procedure for Convenience Sponge Cakes
Authors: Grau H. , Wehrle K. , Arendt E. K. 
Published: June 2007

ABSTRACTTypical examples of convenience foods in the bakery section include partially baked bread, rolls, croissants, and crumpets. The effects of processing variables on sponge cake characteristics were studied in a two‐step baking procedure. A fractional two‐factorial design was applied to describe the effects of the predictor variables on product properties. Flour type, oven type, and baking time in each baking phase were selected as categorical predictor variables on the basis of preliminary baking tests. The performance of a microwave oven was compared with that of a conventional oven. The properties of the new twice‐baked products were characterized and compared with those of a standard product by using the results derived from baking tests, color measurements, and texture analyses. Correlation analysis was used to detect relationships between the response variables. Significant relationships between baking test values and texture analysis values closely related to aspects of microwave cooking were found.
Increase in Bone Calcification in Young Rats Fed Breads Highly Fortified with Calcium
Authors: Ranhotra G. S. , Gelroth J. A. , Leinen S. D. 
Published: June 2007

ABSTRACTBreads were prepared with flour fortified with calcium (Ca) at four levels: 211 (U.S. enrichment standard), 446, 924, and 1,412 mg/100 g of flour. Corresponding diets prepared with these breads and fed to growing rats for four weeks provided 25 (diet A), 50 (diet B), 100 (diet C), and 150% (diet D) of their Ca requirement. After four weeks, the Ca content of the femurs of these rats had increased significantly as Ca in the diet increased up to 100% of requirement but not beyond. The increase in femur strength was significant only between diet A and diet B. Apparent Ca absorption increased as Ca in the diet increased, but Ca absorbed from diet D was not retained any better than that absorbed from diet C. Overall, the data suggested that Ca in highly fortified breads was well absorbed and retained, and that the rats' Ca status early in life was greatly improved. Flour fortified with Ca up to the 924‐mg level (4.4× the mandated enrichment level) had no adverse effect on bread quality. These breads can be labeled a “good source of ” or “high in” Ca.
Development of a Panel of Specific Monoclonal Antibodies to High Molecular Weight Glutenin Subunits and Their Application in Genetic Screening
Authors: Giersch Thomas M. , Hill Amanda S. , Skerritt John H. 
Published: June 2007

ABSTRACTHigh molecular weight glutenin subunits (HMW‐GS) encoded by different chromosomal loci and alleles (1, 2, 5, 7, 10, and 12) were purified using reversed‐phase HPLC from reduced, aqueous propanol extracts of flour from aneuploid or null wheat lines. Unlike previous libraries of monoclonal antibodies developed in our laboratory to SDS‐extracted or alkylated HMW‐GS, several of the monoclonal antibodies (mAb) developed in this study had a range of specificity patterns for HMW‐GS in enzyme‐linked immunosorbent assay (ELISA) and on immunoblots. A subset of the mAb bound either x‐ or y‐type HMW‐GS but not other gluten proteins, while a few antibodies bound one (mAb 110622, 110421, 140820), or two (mAb 101319, 110804, 140705, 1410460) HMW‐GS expressed in each cultivar tested. In most cases, antibodies bound equally to the subunits encoded by different HMW‐GS alleles. The more specific antibodies should be useful in research on the quantitative variation of HMW‐GS expression and in studies of the role of particular HMW‐GS in dough structure. The mAb 101319, which was prepared to subunit 1, bound to HMW‐GS 1Bx subunits in ELISA and on immunoblots. This antibody also provided a higher absorbance value in ELISA with extracts of wheat lines expressing the Glu‐Ble allele (HMW‐GS 20) compared with the Glu‐Bli allele (HMW‐GS 17+18). Another mAb (110622) detected subunit 2 more strongly than subunit 5 in ELISA and produced a higher signal in immunoblots with subunit 2 even though these subunits are >98.7% homologous in amino acid sequence. An ELISA assay using this antibody was optimized for discrimination of wheat lines with the allelic pairs of subunits 1Dx5‐1Dy10 from those with 1Dx2‐1Dy12, with the former lines providing stronger dough properties and superior breadmaking quality. The performance of this assay was unaffected by other variations at HMW‐GS loci and was demonstrated in sets of biotypes, doubled haploid, and cross‐bred breeder's lines.
Chemical Composition of Barley Cultivars Fractionated by Weighing, Pneumatic Classification, Sieving, and Sorting on a Specific Gravity Table
Authors: Elfverson C. , Andersson A. A. M. , Åman P. , Regnér S. 
Published: June 2007

ABSTRACTFive different barley cultivars, including covered and naked samples containing low, normal, or high‐amylose starches were fractionated by weighing, pneumatic classification, sieving, or sorting on a specific gravity table, and analyzed for content of starch, protein, ash, and β‐glucan. For ash content, almost no variation could be found between different fractions. Protein content was minimum in the intermediate fractions for all cultivars when sorted by weighing. For the other fractionation methods, the differences in protein content were small. A tendency for decreasing content of starch with increasing grain mass and size could be seen when fractionating grains by weighing and sieving, respectively. The clearest trend was seen in differences in β‐glucan content for all cultivars and all methods used. The main interpretation of our results is, however, that the chemical composition within the cultivars studied is very similar for all fractions, and that the differences between the unfractionated barley samples are larger.
Enthalpic Transitions in Native Starch Granules
Authors: Sahai D. , Jackson D. S. 
Published: June 2007

ABSTRACTCrystalline properties of native starch granule fractions that varied in apparent density and size were investigated using differential scanning calorimetry (DSC). Endotherms obtained at 80% hydration showed significant variations in enthalpy between the six fractions. Typical bi‐phasic endotherms exhibiting significant variation in start temperature were obtained for the six fractions at 50% hydration. However, on annealing at 50°C/50% hydration for 48 hr, all fractions showed a single endotherm without any significant variability in endotherm characteristics. At 10% hydration, the six fractions exhibited single high‐temperature endotherms with significant differences in their peak temperatures. It was observed that mechanically damaging starch, resulted in the disappearance of any enthalpic transition. These observations could not be satisfactorily explained on the basis of prevailing concepts about DSC enthalpic transitions.
Effect of Infrared Baking on Wheat Flour Tortilla Characteristics
Authors: Martínez‐Bustos F. , Morales S. E. , Chang Y. K. , Herrera‐Gómez A. , Martínez M. J. L. , Baños L. , Rodríguez M. E. , Flores M. H. E. 
Published: June 2007

ABSTRACTA new and improved method for baking wheat flour tortillas was evaluated. The method was faster and reduced tortilla dehydration. The aim of the study was to evaluate the efficiency of the infrared baking method on rollability, puffing, layering, color (lightness), and texture (cutting force and tensile strength) characteristics of wheat tortillas formulated and formed by the traditional (hand‐rolled) and commercial (hot‐press) methods. These tortillas were also compared with traditional tortillas cooked on a hot griddle and commercial tortillas cooked in a three‐tier, gas‐fired oven. In the infrared radiation (IR) method, tortillas were baked for 17 or 19 sec by IR using black‐body radiation at a selected wavelength band and emission temperatures of 549 or 584°C. IR‐baked tortillas showed good characteristics of rollability, puffing, layering, color, and texture. The loss of moisture during baking of the tortillas formed by hot‐pressing and baked by IR was significantly lower than that of tortillas baked by traditional and commercial methods. X‐ray diffraction of tortillas prepared by the traditional process and baked by the IR method showed a pattern similar to that of homemade tortillas baked on a hot griddle. The average energy used by the IR oven was less than that used in the commercial method which, in turn, is more efficient than the traditional hot griddle method.
Protein Distribution in Gluten Products Isolated During and After Wet‐Milling of Maize Grains
Authors: Landry J. , Delhaye S. , Di Gioia L. 
Published: June 2007

ABSTRACTThe protein distribution in five gluten samples isolated during and after wet‐milling of maize grains (slurry before and after filtration, total industrial gluten meal, and coarse and fine fractions obtained after sieving) was investigated by sequential extraction. Six fractions (FI‐FVI), including residue, were isolated. Heating filtered slurry to draw water away did not alter protein distribution. Compared with values reported in the literature for endosperm protein, we found a decrease in FI and FIV, respectively, extracted with salt alone and with reductant, due to proteolysis and partial elimination of nonprotein nitrogen during slurry filtration, and an increase in FII and decrease in FIII, alcohol‐soluble proteins extracted without and with reductant, respectively, due to the presence of SO2 in the steeping liquor. Gluten, with respect to the endosperm from which it originated, was richer in zeins (FII + FIII) and glutelins (FV + FVI) due to partial removal of salt‐soluble proteins (FI + FIV) during the isolation process.
Effects of Modulated Differential Scanning Calorimetry (MDSC) Variables on Thermodynamic and Kinetic Characteristics During Gelatinization of Waxy Rice Starch
Authors: Lai Vivian M.‐F. , Lii Cheng‐Yi 
Published: June 2007

ABSTRACTThe total, reversing, and nonreversing thermal properties during gelatinization of waxy rice starch (starch‐to‐water ratio = 1:2, w/w) were examined by modulated differential scanning calorimetry (MDSC). The effect of MDSC operating variables (i.e., the amplitude and frequency of temperature modulation and the underlying heating rate) on these thermal properties was determined by response surface methodology (RSM) and statistical analysis. The frequency of temperature modulation and the underlying heating rate significantly influenced the gelatinization temperatures and enthalpy changes in total and nonreversing endotherms. In addition, the combination of 0.025Hz and 4–8°C/min with a properly low degree of oscillation was suitable for characterization of starch gelatinization by MDSC. The enthalpy changes in the reversing (thermodynamic) endotherms increased, but those in the nonreversing (kinetic) endotherms decreased with increasing periods (i.e., decreasing frequencies) and underlying heating rates. However, the total enthalpy changes were only slightly influenced by the MDSC variables studied. In addition, the activation energies for the total and nonreversing events were 281.8–417.3 and 386.3–739.7 kJ/mol, respectively, depending on the MDSC conditions. From the compensation relationship between the activation energy and frequency factor, we concluded that the total and nonreversing endotherms were linked to the same single transition.
Use of Extensibility to Measure Corn Tortilla Texture
Authors: Suhendro E. L. , Almeida‐Dominguez H. D. , Rooney L. W. , Waniska R. D. , Moreira R. G. 
Published: June 2007

ABSTRACTAn objective extensibility test was evaluated to measure texture of corn tortillas. A tortilla strip is pulled apart by a tensile force during the test. Force at 1 mm deformation, force required to rupture the tortilla strip, modulus of deformation, and extensibility distance were correlated to subjective rollability and flexibility scores. Hard, firm tortillas required more force to deform and to rupture and had greater moduli of deformation than soft, flexible tortillas. Tortilla texture was affected by manufacturer of commercial tortillas and by aging. The coefficient of variation ranged from 6.0 to 16.7% for force at 1 mm deformation and work required to rupture, respectively. The extensibility technique is sensitive, fast, simple, and repeatable.
Annealing of Long‐Term Stored Rice Grains Improves Gelatinization Properties
Authors: Yamamoto Aijiro , Shirakawa Kiyoka 
Published: June 2007

ABSTRACTWe found new characteristics of annealing (or warm water treatment) in this rheological study. Japonica rice grains from long‐term storage at an ambient temperature for 10–24 years showed gelatinization properties analogous to that of indica rice but recovered properties similar to that of newly harvested rice after annealing at 55°C for 24 hr. Annealing signifcantly augmented the enthalpy from differential scanning calorimetry of raw and treated rice. This treatment also strengthened peak heights of the A pattern of rice in the X‐ray diffraction intensity diagram. Annealing of long‐term stored rice grains showed reverse effects to that of newly havested rice and purified starches. This effect of annealing on long‐term stored rice might be useful for industrial purposes.
Effect of Batter Solids and Starch Type on the Structure of Baked Starch Foams
Authors: Lawton J. W. , Shogren R. L. , Tiefenbacher K. F. 
Published: June 2007

ABSTRACTThe effects of starch type on the properties of baked starch foams were investigated. Starch types used for baking were normal corn, normal potato, waxy corn, high‐amylopectin potato, wheat, and tapioca. Solids content of the starch batters used to bake foam trays ranged from 25 to 45%. Processing parameters and physical properties of the foams were examined. Starch‐foamed trays were formed by heating a starch batter inside a closed mold. Scanning electron micrographs showed that the thin‐walled foamed trays have a dense outer skin and a less dense interior with large cells. The weight of the foamed trays and density of the foam depended on the amount of batter cooked inside the mold, the percent solids of the batter, and the type of starch used. The high‐amylopectin starches made the lightest trays, while the normal cereal starches made the heaviest trays. Baking time depended on percent solids of the batter, the batter volume added to the mold, and starch type. The normal cereal starches had the longest baking times and the high‐amylopectin starches had the shortest baking times Strength and flexibility of the trays are correlated with tray weight and foam density. Heavier trays had greater strength and less flexibility than did lighter trays. Physical properties of the trays can be tailored to meet specific criteria by changing the starch type used and the batter solids.
Biochemical Characterization of the Wheat Waxy A Protein and Its Effect on Starch Properties
Authors: Demeke T. , Hucl P. , Abdel‐Aal E.‐S. M. , Båga M. , Chibbar R. N. 
Published: June 2007

ABSTRACTGranule bound starch synthase1 (GBSS1) is a key enzyme in amylose biosynthesis and is encoded by the A, B and D GBSS1 wx loci in wheat. Wheat lines with mutations at the three GBSS1 loci have been identified. We have characterized and compared the grain starch of CDCW6 wheat line (null B and D for GBSS1) with PI235238 (null A and B for GBSS1), waxy (null A, B and D for GBSS1), and AC Reed (wild type wheat) grain starches. The grain starch of waxy, CDCW6, PI235238, and AC Reed lines contained ≈0, 12, 23, and 25% amylose (w/w), respectively. Waxy, partially waxy, and wild wheat grain starches showed significant differences in onset and peak transition temperatures as determined by differential scanning calorimetric analysis. Grain starches extracted from waxy, CDCW6, and PI235238 also had higher enthalpy of gelatinization values than did wild wheat starch. X‐ray diffraction analysis revealed the highest crystallinity for starch extracted from waxy wheat, followed by CDCW6. The starch produced from the CDCW6 line may find special food and industrial applications because of its relatively low amylose concentration.
Effect of Free Fatty Acids Addition on Corn Grits Extrusion Cooking
Authors: Desrumaux A. , Bouvier J. M. , Burri J. 
Published: June 2007

ABSTRACTThe influence of added fatty acids on extrusion cooking of corn grits and extrudate properties was studied. Samples with three average corn grits particle sizes were processed in a twin‐screw extruder; fatty acids content (0.2–0.8%, wb) varied, and experimental conditions were kept constant (moisture content 18.4% wb, barrel temperature 150°C, screw speed 165 rpm). The effect of adding fatty acids was studied by analyzing water solubility and absorption indices, expansion indices, and mechanical (puncture test) and structural (computerized image analysis) extrudate properties. When fatty acids were added, water solubility and absorption indices decreased, radial expansion index decreased, longitudinal expansion index increased, number of cells increased, and mechanical resistance of extrudates decreased. The influence of added fatty acids was attributed to the formation of fatty acids‐amylose complexes.