bluuebunny/crossref_metadata_2025_split huggingface dataset:
Changes in Nixtamalized Corn Flour Dependent on Postcooking Steeping Time
Authors: Fernández‐Muñoz J. L. , Rodríguez M. E. , Pless R. C. , Martínez‐Flores H. E. , Leal M. , Martinez J. L. , Baños L. 
Published: June 2007

ABSTRACTWe studied the effect of steeping time on various physical and chemical properties of maize flour prepared by the traditional nixtamalization process as well as in oversaturated calcium ion conditions. The calcium content of the corn flour was measured by atomic absorption spectroscopy and was correlated with X‐ray diffraction, viscosity, and pH measurements. Calcium content of the flour showed a nonlinear dependence on steeping time, with a local calcium maximum occurring at ≈7 hr. The pH level of the corn flour increased with steeping time, thus roughly following the time trend shown by the steeping time dependence of the calcium content. Flour crystallinity and peak viscosity of water suspensions of the flour reached maximal values at ≈7–9 hr of steeping, in agreement with manufacturing experience showing that these are appropriate steeping times to prepare tortillas with the desirable rheological and organoleptic properties.
Effects of Product Temperature and Moisture Content on Viscoelastic Properties of Glutinous Rice Extrudates
Authors: Chao‐Chi Chuang George , Yeh An‐I 
Published: June 2007

ABSTRACTThe viscoelastic properties of glutinous rice flour extruded at moisture contents of 45–55% and barrel temperatures of 75–95°C have been investigated using a small amplitude oscillatory rheometer. High moisture contents (50 and 55%) resulted in product temperatures 3–5°C lower than the barrel temperatures. It appeared that the moisture content was a key element in influencing the value of G′ and tan δ. Raising product temperature reduced the difference in G′ caused by the moisture content. When the product temperature was >85°C, the extrudates yielded a similar degree of gelatinization despite the difference in moisture content. Meanwhile, both G′ and G″ decreased due to the disintegration of starch granules. The relationship between the energy input, measured as specific mechanical energy, and the viscoelastic properties was also assessed.
Prediction of Texture of Cooked White Rice by Near‐Infrared Reflectance Analysis of Whole‐Grain Milled Samples
Authors: Meullenet Jean‐Francois , Mauromoustakos Andy , Horner Teri Bellman , Marks Bradley P. 
Published: June 2007

ABSTRACTAlthough much work has been done using near‐infrared (NIR) spectroscopy with rice, little is currently known about the effectiveness of NIR to predict functional attributes of rice such as cooked rice texture, especially as they are influenced by postharvest parameters. In this study, NIR spectroscopy was used for predicting cooked rice texture as affected by postharvest history. Cooked rice texture attributes were evaluated by a nine‐member trained descriptive panel, and milled white rice was scanned using a near‐infrared (NIR) spectrophotometer. Sensory attribute models were developed using partial least squares regression in combination with jack‐knife, a model optimization method, using NIR reflectance spectra (400–2,500 nm) and 1st and 2nd derivatives. Cooked rice adhesion to lips (R2 = 0.88), hardness (R2 = 0.79), cohesiveness of mass (three chews) (R2 = 0.79), and toothpack (R2 = 0.85) were satisfactorily fitted (n = 201–202) using the 2nd derivative spectra. Other attributes evaluated, such as cohesiveness of mass (eight chews) (R2 = 0.69), roughness of mass (R2 = 0.49), and toothpull (R2 = 0.76) were less successfully modeled. In addition, jack‐knife significantly improved model statistics. Overall, NIR spectroscopy had potential application for predicting cooked rice texture. This finding is especially significant for applications such as breeding programs, where the amount of material available is limited.
Steady and Dynamic Shear Rheological Properties of Starch and Decolorized Hsian‐tsao Leaf Gum Composite Systems
Authors: Lai Lih‐Shiuh , Liao Chih‐Lun 
Published: June 2007

ABSTRACTRapid Visco Analyser (RVA) and dynamic rheological measurements were performed on a mixture of decolorized hsian‐tsao leaf gum (dHG) and starch as a function of starch‐to‐gum ratio (S/G 0:6, 1:5, 2:4, 3:3, 4:2, 5:1, and 6:0), starch type (wheat, corn, and tapioca), and total solid content (2, 3, and 4%). Under S/G of 5:1, 4:2 and 3:3, dHG interacted with starch synergistically, which resulted in a marked increase in viscosity during cooling. The storage modulus of the resulting mixed gel was higher than the loss modulus, and both moduli were almost frequency‐independent throughout the frequency range tested, indicating that the composite gels could be classified rheologically as elastic gels. Mixed systems with tapioca starch showed higher pseudo‐gel viscosity in the RVA test, but lower storage modulus in the dynamic test than those with wheat or corn starch. Such results implied that tapioca starch contributed a more viscous property but wheat and corn starch contributed a more elastic property to the mixed systems.
Effects of Heat‐Moisture Treatment and Lipids on Gelatinization and Retrogradation of Maize and Potato Starches
Authors: Miyoshi Emako 
Published: June 2007

ABSTRACTEffects of heat‐moisture treatment (HMT) and lipids on the structure and gelatinization of maize and potato starches were studied, and the retrogradation process of 20% HMT starch gels was also investigated. Maize starch was physically modified by HMT or by defatting. Potato starch was physically modified by HMT or by adding monoglycerides. The X‐ray pattern of the HMT maize starch was assigned to a combination of A and V patterns, which indicated that HMT formed crystallized amylose complexes and recrystallized amylose in maize starch granules. However, the X‐ray pattern of defatted maize starch did not change for HMT, so the lipids originally existing in starch granules were important to the formation of new crystallites during this treatment. Differential scanning calorimetry (DSC) results suggested that weaker structures in amylopectin crystallites were more susceptible to degradation after HMT, while crystallized amylose complexes developed thermal stability after treatment. The amylose contents increased with increasing degree of HMT, which suggested that the newly created amylose arose from exterior linear chains of amylopectin degraded by the treatment. Investigation of retrogradation process showed that HMT significantly promoted retrogradation of starch gels, especially the initiation of recrystallization.
Metabolite Profiling—A Fractionation Method for Analysis of Major and Minor Compounds in Rice Grains
Authors: Frenzel Th. , Miller A. , Engel K.‐H. 
Published: June 2007

ABSTRACTA metabolite profiling methodology was developed using rice as model crop. The approach is based on consecutive extraction of lipids and polar compounds and subsequent fractionations of both extracts. Transesterification‐solid phase extraction (lipids) and selective hydrolysis of silylated derivatives (polar compounds) are applied to separate major from minor constituents. The method covers a broad spectrum of chemical classes. Preliminary investigation of the four fractions by gas chromatography/mass spectrometry (GC/MS) analysis of silylated derivatives identified more than 100 compounds. This unbiased approach can serve as an additional analytical tool for the safety assessment of genetically modified crops and may help to increase the chance to detect unintended effects due to the application of recombinant DNA techniques.
Reflectance and Transmittance Spectroscopy Applied to Detecting Fumonisin in Single Corn Kernels Infected with Fusarium verticillioides
Authors: Dowell Floyd E. , Pearson Tom C. , Maghirang Elizabeth B. , Xie Feng , Wicklow Donald T. 
Published: June 2007

ABSTRACTReflectance and transmittance visible and near‐infrared spectroscopy were used to detect fumonisin in single corn kernels infected with Fusarium verticillioides. Kernels with >100 ppm and <10 ppm could be classed accurately as fumonisin positive or negative, respectively. Classification results were generally better for oriented kernels than for kernels that were randomly placed in the spectrometer viewing area. Generally, models based on reflectance spectra have higher correct classification than models based on transmittance spectra. Statistical analyses indicated that including near‐infrared wavelengths in calibrations improved classifications, and some calibrations were improved by including visible wavelengths. Thus, the color and chemical constituents of the infected kernel contribute to classification models. These results show that this technology can be used to rapidly and nondestructively screen single corn kernels for the presence of fumonisin, and may be adaptable to on‐line detection and sorting.
Effect of Lactic Acid on Protein Solubilization and Starch Yield in Corn Wet‐Mill Steeping: A Study of Hybrid Effects
Authors: Dailey Oliver D. 
Published: June 2007

ABSTRACTTo better understand the role of lactic acid (LA) in corn wet‐milling, steeping studies were performed on different yellow dent corn hybrids using four different solutions containing LA, sulfur dioxide (SO2), a combination of LA and SO2, or no added chemicals. Although there was variation in protein solubilization among the hybrids, protein release was consistently higher when LA was included in the steepwater than when it was excluded (both with and without SO2). Several groups have reported that starch recoveries are improved when steepwater contains LA. To explore the relationship between protein solubilization and starch yield as effected by LA, several yellow dent hybrids were steeped in 0.20% SO2 and 0.50% LA‐0.20% SO2 solutions and milled to recover starch by a 100‐g laboratory corn wet‐milling procedure. In all instances, both starch yields and protein solubilization were enhanced in solutions containing LA. These results support the hypothesis that direct dissolution of the endosperm protein matrix by LA contributes to the improved starch recoveries.
Oat Bran Fermentation by Rye Sourdough
Authors: Degutyte‐Fomins Laima , Sontag‐Strohm Tuula , Salovaara Hannu 
Published: June 2007

ABSTRACTHydration of oat bran including fermentation by rye sourdough was studied. Three types of oat bran suspensions were prepared (a control, one with whole meal rye flour added, and one with rye starter added). The suspensions were incubated for 1, 2, 3 and 4 hr. β‐Glucan content and solubilities of protein and β‐glucan were analyzed. Viscosity of the supernatants of oat bran suspensions was determined. Neither the rye sourdough nor the rye flour alone had a significant effect on the total β‐glucan content of oat bran suspensions. However, the addition of rye, either as whole meal rye flour or as sourdough starter, markedly increased the solubility of β‐glucan and proteins and simultaneously decreased the viscosity of the water‐soluble fraction of oat bran suspension. This suggests that a hydrolysis of β‐glucan had occurred that could change the rheological properties of oat bran in baking and the physiological potential of oat bran in nutrition.
End‐Use Quality of Hard Red and Hard White Spring Wheat Contaminated with Grain of Contrasting Classes
Authors: Habernicht Debra , Martin John M. , Talbert Luther E. 
Published: June 2007

ABSTRACTShort growing seasons and lack of water limit the number of crops that can be productively grown in the Northern Great Plains, but wheat is uniquely adapted to the region. Growers interested in diversification of their operations are growing more than one class of wheat to target different markets. This has led to the challenge of maintaining class purity, in that contamination with alternate classes results in lower prices to the farmer. The primary rationale is that mixtures may have poor end‐use quality. In these experiments, we tested hard red spring wheat and hard white spring wheat contaminated with different levels of soft white spring wheat, durum wheat, hull‐less barley, and the hard wheat of the alternate kernel color for milling and baking quality. Our results showed that contamination of hard red and hard white spring wheat with soft white wheat and hull‐less barley often influenced end‐use quality in that flour yield was negatively affected at relatively low levels. Loaf volume was normally only affected at higher levels. Durum wheat contamination caused fewer quality problems at generally higher levels of contamination. Contamination of hard red or hard white wheat by hard wheat of the alternate color class rarely affected quality, and effects were both positive and negative, depending on quality attributes of the pure samples. Growers wishing to diversify by growing both hard red and hard white wheat would benefit if buyers and end users were willing to accept higher levels of contamination for alternate classes that are unlikely to cause problems in eventual end use.
Proteolytic Enzymes in Germinating Rye Grains
Authors: Brijs Kristof , Trogh Isabel , Jones Berne L. , Delcour Jan A. 
Published: June 2007

ABSTRACTThe proteolytic activities during rye (Secale cereale L. ‘Humbolt’) grain germination were monitored using in‐solution methods and one‐ and two‐dimensional PAGE with gels that contained incorporated substrate proteins. The total proteolytic activity increased during the first three days of germination, but not after that. The proteinase activity was measured at pH 3.8, 6.0, and 8.0 in the presence and absence of class‐specific proteinase inhibitors. This indicated that enzymes from all four proteinase classes were present during the germination process. Germinated rye grain contained mainly aspartic and cysteine proteinase activities that are especially active at pH 3.8. Serine‐ and metallo‐proteinases were less abundant. Overall, the pattern of hydrolysis was very similar to that observed during barley and wheat germination.
Air Classification of Pin‐Milled Soybean Hulls
Authors: Wolf Walter J. , Sessa David J. , Wu Y. Victor , Thompson Arthur R. 
Published: June 2007

ABSTRACTCommercial soybean hulls (14.6% crude protein) were pin milled and then air classified into five fractions to determine whether the hull structure can be disrupted and the protein constituents concentrated. The number of pin millings had only a small effect on the weight distribution of the five fractions. After one grinding, the sum of fractions 1 and 2 (<15–18 μm) represented only 3% of total hulls, and on three grindings, they amounted to only 6% of the hulls. Fraction 3 (19–24 μm) shifted from 16 to 20% with three grindings, while fraction 4 (25–30 μm) remained unchanged at 5%. Fraction 5 (>30 μm) shifted from 75 to 69% on three pin millings to compensate for the shifts noted in fractions 1–3. Scanning electron microscopy revealed that fractions 1 and 2 consisted of the parenchymal cell layers (innermost portion) of the hulls; these fractions had three times the protein content and more than twice the amount of lipids found in the ground starting material. Fraction 3 contained many of the hourglass cells typically found in the middle layer of the hulls plus parenchyma cell material and exhibited about twice the amount of protein and lipid found in the starting hulls. Fraction 4 included large hourglass cells plus globular material and contained about twice the amount of protein and about one and one‐half times the lipid of the starting material. Fraction 5 consisted primarily of clumps of palisade cells (outer cellular layer) adhering to each other and had a lower protein and lipid content than the starting hulls. Thus, pin milling causes some selective disruption of the hulls where parenchyma cell layers and hourglass cells are partially released. The palisade cells, however, are the most difficult to disrupt and constitute the fraction most resistant to pin milling. Our findings suggest that pin milling soybean hulls in combination with air classification can be used to concentrate the proteins and lipids in the fines fractions.
Stress‐Strain Analysis and Visual Observation of Wheat Kernel Breakage During Roller Milling Using Fluted Rolls
Authors: Fang Chaoying , Campbell Grant M. 
Published: June 2007

ABSTRACTThe endosperm and bran of a wheat grain have different mechanical properties and break differently under the same stresses. Stress‐strain analysis was used to model the factors affecting wheat kernel breakage during milling using fluted rolls. The planes of principal compressive and tensile stress and the maximum shear stresses, along which the kernel is most likely to be broken, were calculated for a sharp‐to‐sharp roll disposition. With the occurrence of compressive stress in the horizontal direction and shear stress in the vertical direction, a kernel tends to break along a principal tensile stress plane because the tensile strength of the endosperm is much smaller than its compressive strength. The model presented quantifies the mathematical relationship of three design and operational factors affecting the principal stresses and the maximum shear stresses: roll gap, differential, and roll diameter. High‐speed video was used to observe wheat breakage events during milling; the results show consistency with the theoretical analysis.
Fate of Bt Protein and Influence of Corn Hybrid on Ethanol Production
Authors: Dien B. S. , Bothast R. J. , Iten L. B. , Barrios L. , Eckhoff S. R. 
Published: June 2007

ABSTRACTCorn hybrids were compared to determine the fate of recombinant Bt protein (CRY1Ab from Bacillus thuringiensis) in coproducts from dry grind and wet‐milled corn during production of fuel ethanol. Two pairs of Bt and non‐Bt hybrids were wet milled, and each fraction was examined for the presence of the Bt protein. Bt protein was found in the germ, gluten, and fiber fractions of Bt hybrids. In addition, one set of Bt and non‐Bt hybrids were treated by the dry‐grind ethanol process and Bt protein was monitored during each step of the process. The Bt protein was not detected after liquefaction. Subsequent experiments determined that the Bt protein is rapidly denatured at liquefaction temperatures. Finally, five hybrids were compared for ethanol yield after dry grinding. Analysis of fermentation data with an F‐test revealed the percent of total starch available for conversion into ethanol varied significantly among the hybrids (P < 0.002), indicating ethanol yield is not exclusively dependent on starch content. No difference, however, was observed between Bt and non‐Bt corn hybrids for either ethanol productivity or yield.
Use of Partially Defatted Peanut Flour in Breakfast Cereal Flakes
Authors: Cheewapramong P. , Riaz M. N. , Rooney L. W. , Lusas E. W. 
Published: June 2007

ABSTRACTExtruded breakfast cereal flakes were made by replacing corn cones with nonroasted partially defatted peanut flour (PDPF) and roasted partially defatted peanut flour (R‐PDPF) at various levels (10, 20, and 30%). The mixtures were extruded using a corotating twin‐screw extruder to produce collets. The collets were flaked and then toasted. The extruded toasted flakes were analyzed for physical, physicochemical, and sensory characteristics. Moisture content, bulk density, hardness (force to break), color, bowl life, water absorption, and water solubility indices were significantly affected by the amount of PDPF and R‐PDPF added in the formulation. A sensory panel found extruded toasted flakes made from corn cones and up to 20% R‐PDPF were acceptable as control. Peanut flavor intensity was also evaluated. Surprisingly, peanut flavor intensity was the highest for flakes containing 30% PDPF, rather than those containing 30%R‐PDPF.
Physicochemical Properties of Sonicated Mung Bean, Potato, and Rice Starches
Authors: Chung Koo Min , Moon Tae Wha , Kim Hyunjung , Chun Jae Kun 
Published: June 2007

ABSTRACTMung bean, potato, and rice starch solutions (5%, w/w) were sonicated for up to 5 min after heating, and their physicochemical properties were investigated. Alkaline viscosities, including the apparent and inherent viscosities of starches, decreased. The residues of the swollen starch granules after pasting and centrifugation were also reduced prominently by sonication. Average degree of polymerization did not change with sonication. The starch paste became more transparent, and the hot paste viscosity measured at 70°C decreased remarkably. Results indicate that changes in the physicochemical properties of starch were induced by the disruption of swollen granules rather than the breakage of glucosidic linkages with sonication.
Spelt (Triticum spelta L.) Pasta Quality: Combined Effect of Flour Properties and Drying Conditions
Authors: Marconi E. , Carcea M. , Schiavone M. , Cubadda R. 
Published: June 2007

ABSTRACTThree spelt genotypes (Rouquin, Redoute, and HGQ Rouquin= Rouquin improved for gluten quality), each characterized by either high or low protein content, were processed to manufacture spaghetti, which was dried at both low (60°C) and high temperature (90°C) to assess the effects of flour properties and drying conditions on spelt pasta quality. Protein content in the spelt flour was considered low at ≈11.4% db and high at ≈13.5% db. Gluten properties, assessed by SDS sedimentation and gluten index values and by alveograph and farinograph parameters varied widely, ranging from poor for Redoute to very good for HGQ Rouquin. Pasta quality was assessed by determining color (L*, a*, and b* values), furosine, and cooking quality (stickiness, bulkiness, firmness, and total organic matter [TOM]). Furosine and color (a* and b* values) were significantly influenced by the intensity of the drying process. TOM and organoleptic judgement (OJ) showed that spelt pastas dried at low temperature, independent of their protein levels, were very poor (TOM ≥ 2.7 g/100 g of dry pasta, OJ ≤ 40), except for HGQ Rouquin which was characterized by good gluten strength. On the other hand, the cooking quality of spelt pastas dried at high temperature showed good values (TOM ≤ 1.8 g/100 g of dry pasta, OJ ≥ 53). The combination of high protein content (≥13.5% db) and high‐temperature drying resulted in the production of satisfactory cooking quality pastas from spelt wheats (TOM ≤ 1.2 g/100 g of dry pasta, OJ ≥ 67).
Objective Texture Measurements of Commercial Wheat Flour Tortillas
Authors: Mao Yufeng , Flores Rolando A. , Loughin Thomas M. 
Published: June 2007

ABSTRACTTexture is a property of major importance in the evaluation of baked products. To determine a sample of commercial ranges for stretchability, rollability, firmness, and Kramer shear cell measurements for wheat flour tortillas using the TA‐XT2 texture analyzer, three separate sets of five tortilla brands purchased from stores in Manhattan, KS, were evaluated. Two brands had two formulations, regular and fat‐free. Significant differences (P < 0.05) in stretchability, firmness, and Kramer shear cell occurred between regular and fat‐free tortillas of one tortilla brand. Significant differences (P < 0.05) also were found among the sets of some tortilla brands. Kramer shear cell and stretchability measurements are recommended because Kramer shear cell measures the force combined with compression, shearing, and extrusion. Stretchability measurements were repeatable and are an important textural property of wheat flour tortillas. Ranges for textural properties for commercial wheat flour tortillas were determined, as well as the variability of the textural methods used.