bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantification of Common Wheat Adulteration of Durum Wheat Pasta Using Real‐Time Quantitative Polymerase Chain Reaction (PCR)
Authors: Alary Rémi , Serin Arnaud , Duviau Marie‐Pierre , Jourdrier Philippe , Gautier Marie‐Françoise
Published: June 2007

Common wheat adulteration of durum wheat pasta was quantified using real‐time duplex polymerase chain reaction (PCR). The total DNA content of pasta was determined by amplifying part of a wheat gene encoding a lipid transfer protein, and common wheat DNA was quantified by amplifying part of the puroindoline‐b gene. Under the conditions defined by this study, for pasta with a theoretical adulteration of 3%, the experimentally determined mean value was 2.6–3.4%, depending on drying temperature. Pure durum wheat pastas were distinguished from adulterated pastas without ambiguity. This study demonstrates the feasibility of using real‐time duplex PCR to quantify common wheat adulteration of pasta dried at high temperature, quantification that was impossible with the French official peroxidase‐marker method.
Creep‐Recovery of Wheat Flour Doughs and Relationship to Other Physical Dough Tests and Breadmaking Performance
Authors: Wang F. C. , Sun X. S.
Published: June 2007

Measurements of creep‐recovery of flour‐water doughs were made using a dynamic mechanical analyzer (DMA) in a compression mode with an applied probe force of 50 mN. A series of wheat flour and blend samples with various breadmaking potentials were tested at a fixed water absorption of 54% and farinograph optimum water absorption, respectively. The flour‐water doughs exhibited a typical creep‐recovery behavior of a noncross‐linked viscoelastic material varying in some parameters with flour properties. The maximum recovery strain of doughs with a fixed water absorption of 54% was highly correlated (r = 0.939) to bread loaf volume. Wheat flours with a large bread volume exhibited greater dough recovery strain. However, there was no correlation (r = 0.122) between maximum creep strain and baking volume. The maximum recovery strain of flour‐water doughs also was correlated to some of the parameters provided by mixograph, farinograph, and TA‐XT2 extension.
Effects of Storage Temperature and Kernel Physical Condition on Popping Qualities of Popcorn Hybrids
Authors: Park Donkeun , Maga Joseph A.
Published: June 2007

Effect of storage temperature before popping and kernel physical properties on popping characteristics were studied using popcorn (Zea mays L.) hybrids harvested in 1997. Popped volume (PV), unpopped kernel ratio (UPK), and popping times were measured from 250 g of moisture‐adjusted kernels stored at 30, 1, and −29°C for one month. Maximum popped volume (MPV) and minimum unpopped kernel ratio (MUPK) at the corresponding optimum moisture contents (OMC) were mathematically calculated from PV, UPK, and moisture content values. MPV was significantly affected by storage temperature before popping. Hybrid significantly affected MPV and MUPK. Moisture content, storage temperature, and hybrid significantly varied popping time of the popcorn hybrids, with moisture content being the most important. Correlation results showed that MPV was negatively correlated with unsound kernel ratio, UPK, and popping time. Moisture adjustment of intact kernels should be done at different storage conditions; high temperature storage required higher moisture than low temperature storage to give the best outcome.
Adaptation of AACC Method 56‐11, Solvent Retention Capacity, for Use as an Early Generation Selection Tool for Cultivar Development
Authors: Bettge A. D. , Morris C. F. , DeMacon V. L. , Kidwell K. K.
Published: June 2007

The solvent retention capacity (SRC) profile is useful for studying flour components contributing to end‐use functionality. The method tests four different solvents with 5 g of flour each. Because of the amount of grain (30–40 g) typically needed to produce 20 g of flour for the SRC test, the method is not well‐suited for assessing end‐use quality of early generation breeding material, where grain quantities are limited. The method was therefore modified to require only 0.2 g of ground wheat instead of 5 g of flour per SRC solvent. The small‐scale SRC results using whole meal had correlations of r = 0.86 for lactic acid, r = 0.85 for sodium carbonate, r = 0.78 for sucrose, r = 0.74 for sodium bicarbonate (the alkaline water retention capacity method) and r = 0.69 for water when compared with SRC values from full‐scale tests using 5 g of flour. Overall, cultivars with SRC values at the extremes of the distribution were in the same ranked order for the small‐ and large‐scale SRC test results. However, variation in ranked order of cultivars between test methods was detected among samples that were not at the extremes of the distribution. Traditionally, successful wheat breeding strategies involve eliminating or advancing lines from the extremes of the distribution to increase the proportion of desirable genotypes within breeding programs. Results indicated that advancing promising germplasm or eliminating germplasm with inferior end‐use quality potential is possible using the small‐scale SRC technique to evaluate early generation wheat breeding material, as a sort of breeding triage.
Quality of Corn Oil Obtained by Sequential Extraction Processing
Authors: Feng F. , Myers D. J. , Hojilla‐Evangelista M. P. , Miller K. A. , Johnson L. A. , Singh S. K.
Published: June 2007

Sequential extraction processing (SEP) is a new approach to fractionating dried, flaked corn using 95% ethanol. In the original process, corn oil was extracted at 76°C in a countercurrent mode while simultaneously dehydrating the ethanol. This resulted in 20% of the protein (predominantly zein) coextracting with the oil. The process was modified to reduce the amount of coextracted protein. One modification (mSEP1) was to use a blend of 30% hexane and 70% ethanol at 56°C. A second modification (mSEP2) used a longer extraction column (L/D ratio 15) to replace the column with L/D 2 used in the original SEP system. To determine the effect of the modifications on oil quality, the quality of the crude corn oils produced from the modified SEP processes were compared with the quality of oil from the original SEP. To evaluate the quality of the three crude oils produced by SEP with the process typically used in industry, they were compared with the quality of laboratory hexane‐extracted corn oil. The results of the three SEP oils exhibited larger concentrations of fatty acids, phospholipids, and carotenoids, smaller concentrations of triacylglycerols, and darker red color than the hexane‐extracted oil. The oils from the two modified SEP processes contained smaller concentrations of free fatty acids and phospholipids and larger concentrations of triacylglycerols and carotenoids than the original SEP oil. In spite of the improvements to the oil through process modifications, the mSEP1 and mSEP2 oils exhibit greater refining losses than hexane‐extracted oil.
Isolation and Characterization of Atriplex hortensis and Sweet Chenopodium quinoa Starches
Authors: Wright K. H. , Huber K. C. , Fairbanks D. J. , Huber C. S.
Published: June 2007

Starches from garden orach (Atriplex hortensis) and sweet quinoa (Chenopodium quinoa Willd. ‘Surumi’) seeds were isolated, examined for compositional characteristics, and compared with bitter quinoa (Cheno‐podium quinoa Willd.) starch. Garden orach and sweet quinoa seeds were similar in fat and ash contents, while garden orach seeds contained ≈10% more protein. Starches were isolated from seeds following a 12‐hr soak in dilute alkaline solution using a series of grinding, screening, centrifugation, and washing steps. Isolated starches viewed by scanning electron microscopy yielded angular, polygonal granules ≈1–2 μm in diameter. Starches displayed typical A‐type crystalline packing arrangements as determined by X‐ray powder diffractometry. Apparent amylose contents for garden orach (21.2%), sweet quinoa (20.6%), and bitter quinoa (19.8%) were determined according to colorimetric procedure. Differential scanning calorimetry data indicated a higher and wider gelatinization temperature range for garden orach as compared with sweet and bitter quinoa starches. Starch pasting profiles generated using a Rapid Visco Analyser indicated a reduced peak paste viscosity for garden orach starch relative to sweet and bitter quinoa and common corn starches.
Pulsed Nuclear Magnetic Resonance (PNMR) Study of Rice Starch Retrogradation
Authors: Yao Yuan , Ding Xiaolin
Published: June 2007

Although pulsed NMR (PNMR) has been used for qualitative study of starch retrogradation in selected systems, validation is necessary for its application to new systems. PNMR was used to analyze the retrogradation of rice starches in purified form, in rice flour, and in cooked rice grains. The standard curves between the relative solid content (S′, %) by PNMR and the percentage of gelatinized starch (GS, %) were determined for common rice flour, common rice starch, and waxy rice starch at different moisture contents. The coefficients of linear regression for these curves (R2) were all >0.997. Starches with different amylose contents were tested for S′ values at the stages of freshly gelatinized, retrograded (4°C, 18 days), and reheated (90°C, 20 min). The S′ of reheated starch (S′reheat) was similar to the S′ of freshly gelatinized starch (S′0), so we concluded that the increase in S′ during storage corresponded to amylopectin retrogradation. The effect of moisture content on retrogradation of rice starch, rice flour, and cooked rice grains was studied by PNMR, and the data were interpreted using the Avami equation. Decreasing the moisture content increased the rate of retrogradation and led to a higher parameter k and a lower parameter n. For moisture content in the range studied, PNMR can be used to follow amylopectin retrogradation of different rice starch systems.
Quantitative Variation of HMW Glutenin Subunits from Hard Red Spring Wheats Grown in Different Environments
Authors: Zhu J. , Khan K.
Published: June 2007

The objective of this study was to investigate the quantitative variation of HMW glutenin subunits in relation to glutenin polymers and hence breadmaking quality across different environments. Six genotypes of hard red spring (HRS) wheat were grown at seven locations in North Dakota in 1998 in a randomized complete‐block experimental design with three replicates at each location. Unreduced SDS‐soluble glutenins of flour were fractionated by multistacking SDS‐PAGE into different sized glutenin polymers, followed by SDS‐PAGE and imaging densitometry to determine the quantitative variation of HMW glutenin subunits. SDS‐insoluble glutenin polymers also were examined for their quantitative composition of HMW glutenin subunits. The results showed that the percentage of HMW glutenin subunits was significantly affected by growing locations. The quantity of HMW glutenin subunits in SDS‐insoluble glutenins was significantly and positively correlated with loaf volume. SDS‐insoluble glutenin polymers had a higher percentage of HMW glutenin subunits than did SDS‐soluble glutenins. SDS‐insoluble glutenin polymers in flour were positively and significantly correlated in proportions of both total and individual HMW glutenin subunits in total SDS glutenins. SDS‐insoluble glutenin polymers also were positively and significantly correlated with the combined proportion of HMW glutenin subunits 2* + 5. The results of this study indicated that either subunit 2* or 5 might be more important in forming a greater quantity of larger SDS‐insoluble glutenin polymers than other subunits. SDS‐insoluble glutenin polymers from different cultivars or locations could have different quantities of HMW glutenin subunits in their composition. SDS‐insoluble glutenin polymers with more HMW glutenin subunits might be larger sized than those with less HMW glutenin subunits. Environment significantly influenced the quantitative variation of HMW glutenin subunits, which in turn affected the size distribution of glutenin polymers, and hence breadmaking quality.
Mechanical Behavior of Oats: The Groat Effect
Authors: Engleson J. A. , Fulcher R. G.
Published: June 2007

To evaluate the mechanical behavior of groats with constant mass and moisture content, individual groats were compressed along the major axis between parallel flat plates. Compression versus tension testing was adapted easily to groats, which are weaker along the major axis. Regression of maximum apparent stress on moisture content suggested that the proportionality constant was a function of an undefined biological difference (UBD) among tested samples and the y‐intercept depended on groat mass and UBD. No brittle‐ductile transition in the range of 9–30% moisture was observed regardless of genotype. Groats in general tended to fail by plastic compression at low moisture content (9–10%). Groats at high moisture content (>12%) generally buckled and burst near the midpoint of the crease, suggesting higher stress around the crease regardless of genotype. Apparent maximum stress should be considered as an average for a genotype. Knowledge of specific groat characteristics (including but likely not limited to mass and moisture) and how they influence apparent mechanical behavior should lead to improvements in oat milling.
Cross‐Linked Resistant Starch: Preparation and Properties
Authors: Woo K. S. , Seib P. A.
Published: June 2007

Resistant starches (RS) were prepared by phosphorylation of wheat, waxy wheat, corn, waxy corn, high‐amylose corn, oat, rice, tapioca, mung bean, banana, and potato starches in aqueous slurry (≈33% starch solids, w/w) with 1–19% (starch basis) of a 99:1 (w/w) mixture of sodium trimetaphosphate (STMP) and sodium tripolyphosphate (STPP) at pH 10.5–12.3 and 25–70°C for 0.5–24 hr with sodium sulfate or sodium chloride at 0–20% (starch basis). The RS4 products contain ≤100% dietary fiber when assayed with the total dietary fiber method of the Association of Official Analytical Chemists (AOAC). In vitro digestion of four RS4 wheat starches showed they contained 13–22% slowly digestible starch (SDS) and 36–66% RS. However after gelatinization, RS levels fell by 7–25% of ungelatinized levels, while SDS levels remained nearly the same. The cross‐linked RS4 starches were distinguished from native starches by elevated phosphorus levels, low swelling powers (≈3g/g) at 95°C, insolubilities (<1%) in 1M potassium hydroxide or 95% dimethyl sulfoxide, and increased temperatures and decreased enthalpies of gelatinization measured by differential scanning calorimetry.
Dynamic and Elongation Rheology of Yeasted Bread Doughs
Authors: Newberry M. P. , Phan‐Thien N. , Larroque O. R. , Tanner R. I. , Larsen N. G.
Published: June 2007

The rheology of yeasted bread doughs is a little‐studied field despite yeast's importance in developing bread structure. A method of thermally inactivating the yeast within mixed bread doughs was developed to overcome the difficulty of yeast fermenting during rheological measurements. Sample stabilization by preshearing of dough samples at a stress amplitude of 1 Pa at 1 Hz for 10 sec improved the reliability of small amplitude oscillatory shear measurements, and resting 20 min within the rheometer was sufficient to produce reliable and consistent observations. Small amplitude oscillatory shear measurements were unable to detect any differences between yeasted and nonyeasted doughs nor any changes in linear viscoelastic properties due to fermentation. However, large strain uniaxial elongation measurements of yeasted doughs revealed a significant progressive decrease in elongational viscosities with fermentation. Size‐exclusion HPLC analysis of yeasted doughs showed an increase in unextractable polymeric dough proteins, which were interpreted as evidence of cross‐linking and therefore a potential improvement in dough properties. The apparent contradictions between uniaxial elongation and SE‐HPLC studies of fermenting yeasted doughs can be attributed to gas bubbles within the dough interrupting the increasingly cross‐linked protein network, resulting in the rheological weakness observed for fermenting yeasted doughs.
Isolation of Small Starch Granules and Determination of Their Fat Mimic Characteristics
Authors: Malinski Edmond , Daniel James R. , Zhang Xia X. , Whistler Roy L.
Published: June 2007

Small starch granules from wheat and amaranth were isolated and examined by light microscopy (wheat), scanning electron microscopy (wheat and amaranth), and rapid viscosity (RVA) analysis. The isolated wheat and amaranth starches were incorporated into reduced‐fat frozen dessert mixes (2%, w/w) and the frozen desserts were characterized by sensory analysis for smoothness, creaminess, and preference. The results of the sensory analysis suggest that up to 50% of the fat in a frozen dessert may be replaced when substituted by these starches at the 2% level (w/w).
Soft Wheat Starch Pasting Behavior in Relation to A‐ and B‐type Granule Content and Composition
Authors: Shinde S. V. , Nelson J. E. , Huber K. C.
Published: June 2007

Flours of two soft wheat cultivars were fractionated into native, prime, tailing, A‐, and B‐type starch fractions. Starch fractions of each cultivar were characterized with respect to A/B‐type granule ratio, amylose content, phosphorus level (lysophospholipid), and pasting properties to investigate factors related to wheat starch pasting behavior. While both cultivars exhibited similar starch characteristics, a range of A‐type (5.7– 97.9%, db) and B‐type granule (2.1–94.3%, db) contents were observed across the five starch fractions. Though starch fractions displayed only subtle mean differences (<1%) in total amylose, they exhibited a range of mean phosphorus (446–540 μg/g), apparent amylose (18.7–23%), and lipid‐complexed amylose (2.8–7.5%) values, which were significantly correlated with their respective A‐ and B‐type granule contents. A‐type (compared with B‐type) granules exhibited lower levels of phosphorus, lipid‐complexed amylose, and apparent amylose, though variability for the latter was primarily attributed to starch lipid content. While starch phosphorus and lipid‐complexed amylose contents exhibited negative correlation with fraction pasting attributes, they did not adequately account for starch fraction pasting behavior, which was best explained by the A/B‐type granule ratio. Fraction A‐type granule content was positively correlated with starch pasting attributes, which might suggest that granule size itself could contribute to wheat starch pasting behavior.
Effect of a Cell‐Wall‐Degrading Enzyme Complex on Starch Recovery and Steeping Requirements of Sorghum and Maize
Authors: Serna‐Saldívar Sergio O. , Mezo‐Villanueva Martha
Published: June 2007

The effect of a commercial cell‐wall‐degrading enzyme (CWDE) complex on the steeping time and starch yields of white regular sorghum (RSOR) compared with yellow maize (YMZ) was determined. An in vitro wet‐milling method standardized to test dosages of 0–120 fungal β‐glucanase units (FBG)/100 mL indicated that starch yields were significantly higher for YMZ than RSOR and increased proportionally as enzyme dosage increased. A factorial experiment with a level of confidence of P < 0.05 was performed to study the effect of CWDE addition to coarsely ground grains for 4 hr after 20 or 44 hr of SO2 steeping of whole grains. At both regular steep times, YMZ yielded significantly higher amounts of starch than RSOR. When steep times were compared, grains soaked for 48 hr produced 1.7% higher starch yields than counterparts treated for 24 hr. CWDE significantly increased starch yields and recoveries. Enzyme‐treated grains yielded 2.5% more starch than counterparts steeped regularly. For both grains, the best wet‐milling conditions to obtain the highest amount of starch were 48 hr of steeping and CWDE addition. Under these conditions, YMZ and RSOR yielded 66.9 and 66.6% starch, respectively. Starches obtained after the enzyme treatment at both steep times contained higher amounts of residual protein and ash compared with the untreated counterparts. Rapid viscoamylograph properties of YMZ and RSOR starches were not affected by the use of the CWDE nor the steep time. In comparison with RSOR starch, the YMZ starch initiated gelatinization at lower temperature, had less shear thinning and higher viscosity or setback at the end of cooling.
Effect of Oil Content and pH on the Physicochemical Properties of Corn Starch‐Soybean Oil Composites
Authors: Garzón G. A. , Gaines C. S. , Mohamed A. , Palmquist D. E.
Published: June 2007

Starch‐lipid composites are a new category of fat replacers. The physicochemical properties of reconstituted corn starch and soybean oil composites (CSSBOC) were evaluated and compared with the properties of reconstituted jet‐cooked corn starch (JCCS). Gel firmness, thermal properties, and hot pasting properties at two pH levels and two oil content levels were studied. Amylose content of CSSBOC was unaffected by processing. Buffer pH significantly affected the firmness of the gels made with JCCS. Gels appeared to have a more ordered structure and were firmer at pH 3.4 than at pH 6.0. The firmness of gels made with CSSBOC was not affected by pH or oil content. Retrogradation enthalpy of the gels made with JCCS was significantly affected by pH. Differences in the thermal characteristics of gels made with CSSBOC were attributed to pH and oil content. Peak viscosity, cold paste viscosity, and breakdown viscosity changed significantly when CSSBOC pastes were reconstituted in different pH buffers. Only hot paste viscosity and cold paste viscosity changed significantly when JCCS pastes were reconstituted in different pH buffers. Results establish critical parameters for processing decisions and for the understanding of the behavior of CSSBOC in food system models in which pH is an important factor.
FT‐Raman Spectra of Unsoaked and NaOH‐Soaked Wheat Kernels, Bran, and Ferulic Acid
Authors: Ram M. S. , Dowell Floyd E. , Seitz Larry M.
Published: June 2007

The sodium hydroxide (NaOH) test for determining wheat color class depends on the observation that on soaking in NaOH, red wheat turns a darker red and white wheat turns straw yellow. To understand the mechanism of this test, Raman spectra of wheat bran, wheat starch, ferulic acid, and whole kernels of wheat, before and after NaOH soak, were studied. The major observable components in the whole kernel were that of starch, protein, and ferulic acid, perhaps esterified to arabinoxylan and sterols. When kernels are soaked in NaOH, spectral bands due to ferulic acid shift to lower energy and show a slightly reduced intensity that is consistent with deprotonation of the phenolic group and extraction of a portion of the ferulic acid into solution. Other phenolic acids, alkyl resorcinols, and flavonoids observed in the NaOH extracts of wheat by HPLC were not observed in the Raman spectra. Wheat bran accounts for most of the ferulic acid in the whole kernel, as indicated by the increased intensity of the doublet at 1,631 and 1,600 cm‐1 in the bran. The intense starch band at 480 cm‐1 in whole kernel wheat was nearly absent in the wheat bran.
Extensional Rheology and Stability of Gas Cell Walls in Bread Doughs at Elevated Temperatures in Relation to Breadmaking Performance
Authors: Dobraszczyk B. J. , Smewing J. , Albertini M. , Maesmans G. , Schofield J. D.
Published: June 2007

The rheological properties of gas cell walls in bread doughs are considered to be important in relation to their stability and gas retention during proof and baking. Large deformation rheological properties of gas cell walls were measured using biaxial extension for a number of doughs of varying breadmaking quality at constant strain rate and elevated temperatures of 25–60°C. Strain hardening and failure strain of cell walls both decreased with temperature, with cell walls in good breadmaking doughs remaining stable and retaining their strain hardening properties at higher temperatures (60°C), while the cell walls of poor breadmaking doughs became unstable at lower temperatures (45–50°C) and had lower strain hardening. Strain hardening measured at 50°C gave good correlations with baking volume, with the best correlations achieved between rheological measurements and baking tests that used similar mixing conditions. As predicted by the Considere failure criterion, a strain hardening value of 1 defines a region below which gas cell walls become unstable, and discriminates well between the baking quality of a range of commercial flour blends of varying quality. This indicates that the stability of gas cell walls during baking is strongly related to strain hardening properties, and that extensional rheological measurements can be used as indicators of baking quality.
Centrifuged Liquid and Breadmaking Properties of Frozen‐and‐Thawed Bread Dough
Authors: Seguchi Masaharu , Nikaidoo Seiko , Morimoto Naomi
Published: June 2007

Breadmaking properties (bread height, mm, and specific volume, cm3/g ) showed marked deterioration when bread dough was frozen and stored at ‐20°C for one day. However, these properties of bread dough baked after storage for three to six days were not further deteriorated as compared with that baked after one day of storage. A large amount of liquid was oozed from the frozen‐and‐thawed bread dough. The liquid was separated from the bread dough by centrifugation (38,900 × g for 120 min at 4°C), and collected by tilting the centrifuge tube at an angle of 45° for 30 min. There was a strong correlation between the amount of centrifuged liquid and breadmaking properties (bread height and specific volume). The mechanism responsible for the oozing of liquid in frozen‐and‐ thawed bread dough was studied. The presence of yeast and salt in bread dough was suggested to be closely related to the amount of centrifuged liquid, and fermented products particularly had a large effect on the amount of centrifuged liquid.
Development of Nondestructive Screening Methods for Single Kernel Characterization of Wheat
Authors: Nielsen Jesper Pram , Pedersen Dorthe Kjær , Munck Lars
Published: June 2007

The development of nondestructive screening methods for single seed protein, vitreousness, density, and hardness index has been studied for single kernels of European wheat. A single kernel procedure was applied involving, image analysis, near‐infrared transmittance (NIT) spectroscopy, laboratory density determination, single kernel characterization system (SKCS), and finally Kjeldahl protein determination on the crushed single kernels. Single kernel NIT spectroscopy showed excellent ability to determine protein content, and some ability for determination of single kernel vitreousness. Nondestructive determination of single kernel density, either based on NIT spectroscopy or based on image analysis and kernel weight, needs to be further improved for practical use. The use of SKCS hardness index as a true single kernel hardness reference in a NIT prediction model resulted in a poor predictability. However, by applying an averaging approach, in which single seed replicate measurements are mathematically simulated, a very good NIT prediction model was achieved. This suggests that the single seed NIT spectra contain hardness information, but that a single seed hardness method with higher accuracy is needed to achieve a good NIT prediction model for single kernel hardness.
Hardness Measurement of Bulk Wheat by Single‐Kernel Visible and Near‐Infrared Reflectance Spectroscopy
Authors: Maghirang Elizabeth B. , Dowell Floyd E.
Published: June 2007

Reflectance spectra (400 to 1700 nm) of single wheat kernels collected using the Single Kernel Characterization System (SKCS) 4170 were analyzed for wheat grain hardness using partial least squares (PLS) regression. The wavelengths (650 to 700, 1100, 1200, 1380, 1450, and 1670 nm) that contributed most to the ability of the model to predict hardness were related to protein, starch, and color differences. Slightly better prediction results were observed when the 550–1690 nm region was used compared with 950–1690 nm region across all sample sizes. For the 30‐kernel mass‐averaged model, the hardness prediction for 550–1690 nm spectra resulted in a coefficient of determination (R2) = 0.91, standard error of cross validation (SECV) = 7.70, and relative predictive determinant (RPD) = 3.3, while the 950–1690 nm had R2 = 0.88, SECV = 8.67, and RPD = 2.9. Average hardness of hard and soft wheat validation samples based on mass‐averaged spectra of 30 kernels was predicted and compared with the SKCS 4100 reference method (R2 = 0.88). Compared with the reference SKCS hardness classification, the 30‐kernel (550–1690 nm) prediction model correctly differentiated (97%) between hard and soft wheat. Monte Carlo simulation technique coupled with the SKCS 4100 hardness classification logic was used for classifying mixed wheat samples. Compared with the reference, the prediction model correctly classified mixed samples with 72–100% accuracy. Results confirmed the potential of using visible and near‐infrared reflectance spectroscopy of whole single kernels of wheat as a rapid and nondestructive measurement of bulk wheat grain hardness.
Authentication of Rice Using Near‐Infrared Reflectance Spectroscopy
Authors: Kim Sang Sook , Rhyu Mee‐Ra , Kim Jae Min , Lee Sang‐Hyo
Published: June 2007

The authentication of rice (Korean domestic rice vs. foreign rice) has been attempted using near‐infrared spectroscopy (NIRS). Two sample sets (n1 = 280 and n2 = 200) were used to obtain calibration equations and the spectral regions used for this study were 500–600 nm, 700–900nm, and 980–2,498 nm. Modified partial least square (MPLS) regression was used to develop the prediction model. The standard error of cross validation (SECV) and the r2 were 0.165 and 0.91 respectively for 1st calibration set and 0.165 and 0.93 for 2nd calibration set respectively. The results of the independent validation (n3 = 80) showed that all of 80 samples were identified correctly. Even though authentication of rice was performed successfully using NIRS, the calibration statistics in this study showed that further effort is needed for implementation of NIRS for authentication of rice for industry purposes.
Effect of Storage Time and Temperature on Rheological and Microstructural Properties of Gluten
Authors: Nicolas Y. , Smit R. J. M. , van Aalst H. , Esselink F. J. , Weegels P. L. , Agterof W. G. M.
Published: June 2007

To investigate the effects of frozen storage on the rheological and microstructural properties of gluten, two model systems were investigated: System A, gluten and water; System B, gluten, water, and NaCl. The storage time was varied from 1 to 16 weeks and the storage temperature was varied from ‐5 to ‐30°C. After thawing, uniaxial and biaxial deformations, and stress relaxation measurements were performed on gluten. In System A, the major effects were noticed when the gluten was stored at ‐5°C. Frozen storage induced a decrease in stress and in strain at breaking, but an increase in modulus (stress/strain) under uniaxial deformation. In System B, only stress relaxation measurements showed differences between the fresh gluten and the gluten stored at ‐18°C. These results suggest that at ‐5°C, gluten strands form more entanglements. Microscopic analyses of frozen gluten showed that, during the freezing step, ice crystals compressed the gluten. A significant phase separation was observed between gluten and ice but no difference was observed between the storage time and storage temperature. However, after thawing, gluten microstructure exhibited a structure similar to the fresh gluten, and the structure looks like a sponge (a fine gluten structure with tiny water pockets).
Factors Associated with Dough Stickiness as Sensed by Attenuated Total Reflectance Infrared Spectroscopy
Authors: van Velzen Ewoud J. J. , van Duynhoven John P. M. , Pudney Paul , Weegels Peter L. , van der Maas John H.
Published: June 2007

Attenuated total reflectance (ATR) and Fourier transform infrared (FTIR) spectroscopy have been applied in the characterization of sticky dough surfaces. The characterization provides insight in the chemical distribution of gluten protein, starch, water, and fat during dough kneading. ATR is especially useful for selective sampling of dough surfaces because the depth of penetration of radiation is quite shallow. For dough, it is calculated to be in the order of 0.5–4 μm in the mid‐infrared, ideal for measurements of stickiness effects, where only the dough surface is of interest. To investigate the cohesive and adhesive properties of the individual dough constituents, dough was peeled from the ATR plate to study the material that adhered to it. The infrared spectra obtained indicate that fat and gluten protein appear to be located at the outer sticky dough surfaces, rather than water and starch. In comparison with gluten, the fatty component showed relatively strong adhesive forces to the ATR plate; a high residual fraction was measured after peeling the dough. Gluten proteins display different cohesion and adhesion properties that are strongly dependent on their hydration state. This indicates that the degree of hydration of gluten proteins contributes to the sticky properties of (overkneaded) dough. When analyzing gluten protein in D2O instead of a dough matrix, more or less similar results were obtained. Significant differences in amide I and amide II intensities were measured for kneaded and stretched gluten protein in comparison to untreated, wet gluten. Besides changes in the vibrational properties of the amide groups, conformational changes in the tertiary protein structure also were observed. It appears that kneading and stretching of dough results in a major decrease in α‐helices content, accompanied by an increase of extended β‐sheet conformations.
Asian Salted Noodle Quality: Impact of Amylose Content Adjustments Using Waxy Wheat Flour
Authors: Guo G. , Jackson D. S. , Graybosch R. A. , Parkhurst A. M.
Published: June 2007

Fourteen flour blends of two natural wild‐type wheat (Triticum aestivum L.) flours, ‘Nuplains’ and ‘Centura’, blended with one waxy flour sample were characterized and processed to Asian salted noodles. The flour amylose content range was <1–29%. Damaged starch contents were 10.4, 7.0, and 6.6% for the waxy wheat, Nuplains, and Centura, respectively. The waxy flour farinograph water absorption was as high as 79.5%, ≈20% higher than the wild‐type flours. Because two types of starch granules (wild‐type and waxy) existed in the flour blends, two peaks at 82°C (waxy) and 95°C (wild‐type) were found in the RVA pasting curves. Reduced amylose content caused high flour swelling volume and power and low falling number. Significant effects of flour amylose content on noodle processing and textural (eating) qualities were found in the study. Noodle qualities, as reflected in covariate analysis, were not significantly affected by the flour blend's protein content, SDS‐sedimentation volume, mixograph dough development time, or mixograph tolerance score. The absence of covariate (protein quantity and quality) effects for the food system (flour) used in this study is a very desirable design for the functional studies of starch components. The optimal flour amylose content range for Asian salted noodle products was 21–24%.
Hydrolytic Degradation of Triacylglycerols and Changes in Fatty Acid Composition in Rice Bran During Storage
Authors: Goffman F. D. , Bergman C.
Published: June 2007

Hydrolytic rancidity makes rice bran unsuitable for human consumption, restricting its use to animal feed. To better understand this lipolytic process, bran from rice cultivars ‘Cypress’ and ‘Earl’ differing in oil concentration (23.5 and 18.3 mg of triacylglycerol/100 mg of bran, respectively) was stored at room temperature for five months, and the changes in triacylglycerol content and fatty acid composition, as well as the accumulation of free fatty acids (FFA) were followed. The decomposition of triacylglycerols displayed a decay pattern, with Cypress showing a more elevated degradation rate when compared with Earl. At day 36, both lines reached the same oil concentration, but the triacylglycerol decomposition in Cypress was still higher, indicating that oil concentration may not be a significant factor affecting the intensity of the rancidity process. The higher degradation rate observed in Cypress was apparently caused by higher lipase activity, which was 26% higher (P < 0.001). Fatty acid composition of triacylglycerols changed during storage, the palmitic acid percentage was similarly reduced in both lines to ≈80% of its initial concentration. Oleic and linoleic acids remained almost unmodified or slightly increased. The final content of FFA was ≈58% higher in Cypress than in Earl (P < 0.001). In conclusion, lipase activity appears to be an important factor determining the intensity of the hydrolytic process, but further research is required to confirm this conjecture. If this hypothesis is verified, a selection for lower lipase activity could be useful for increasing rice bran stability.
Effects of Environmental Temperature on Structure and Gelatinization Properties of Wheat Starch
Authors: Matsuki Junko , Yasui Takeshi , Kohyama Kaoru , Sasaki Tomoko
Published: June 2007

The effects of environmental temperature on gelatinization properties and amylopectin structures of wheat endosperm starch were examined by isolating starches from four wheat cultivars matured in growth chambers at daytime temperatures of 15, 20, 25, or 30°C. Kernel weight and starch content per kernel were reduced by high maturation temperature. Amylose content showed no significant change at high maturation temperature in some cultivars; in other cultivars, there was a slight increase. Principal component analysis of data on relative peak areas of debranched amylopectin showed that amylopectin from wheat grown at a lower temperature had a greater proportion of shorter chains. Amylopectin branch chains were classified into three groups based on the correlation coefficients between the data of branch chain length distribution and principal component scores, degree of polymerization (DP) of 6–12, DP 13–34, and DP ≥ 35. The gelatinization temperature of starches increased markedly at a higher maturation temperature, with increases exceeding 10°C at high maturation temperatures. Gelatinization properties correlated significantly with amylopectin chain length distribution.
Extrusion Processing of Rice‐Based Breakfast Cereals Enhanced with Tocopherol from a Chinese Medical Plant
Authors: Lin Yuan‐Hui , Yeh Chia‐Sheng , Lu Shin
Published: June 2007

Brown rice flour was mixed with a Chinese medical plant (Euryale ferox Salisb.) and processed to make ready‐to‐eat breakfast cereals using twin‐screw extrusion. Levels of 15 and 20% feed moisture in flour, and 200 and 250 rpm screw speed were set, and the physicochemical properties and content of α‐, β‐, γ‐, and δ‐tocopherols were determined. The data showed that 15% feed moisture gave a low bulk density and water absorption index but a high expansion ratio and water solubility index. High screw speed (250 rpm) produced a result similar to that of 15% feed moisture. A sample with 85% brown rice flour with 15% E. ferox Salisb. retained the highest content of α‐, β‐, γ‐, and δ‐tocopherols (125, 6, 78, and 9 μg/g), respectively. The optimum extrusion conditions determined were 15% E. ferox Salisb. mixed with brown rice at 15% feed moisture and at 250 rpm screw speed.
Contents of Antioxidant Compounds in Turkish Oats: Simple Phenolics and Avenanthramide Concentrations
Authors: Dokuyucu Tevrican , Peterson David M. , Akkaya Aydin
Published: June 2007

Antioxidant products such as simple phenolic compounds and avenanthramides in oat (Avena sativa L.) may have health‐promoting effects on humans. Therefore, it is very important to determine simple phenolics and avenanthramide concentrations of different genotypes of oats from different regions of the world. The aim of this research was to determine the concentrations of simple phenolics and avenanthramides of Turkish oat genotypes. According to the results, Turkish oat genotypes were significantly different for three major avenanthramides (Bc, Bp, and Bf) and the simple phenolic, ferulic acid (FA), while not significantly different for p‐coumaric acid (PCA). Ferulic acid concentrations of Turkish oat genotypes were higher than a standard U.S. cultivar, Belle. However, the major avenanthramide concentrations of Turkish oat genotypes were significantly lower than Belle.
Composition and Reactivity of A‐ and B‐type Starch Granules of Normal, Partial Waxy, and Waxy Wheat
Authors: Bertolini A. C. , Souza E. , Nelson J. E. , Huber K. C.
Published: June 2007

Wheat has great potential to make inroads into starch markets with the advent of partial waxy and waxy starches of diverse composition and properties. The majority of isolated starch utilized in food applications is chemically modified to improve starch properties according to the intended use. Therefore, it is critical to understand factors that affect wheat starch reactivity. This work investigated the relative reactivities of normal, partial waxy, and waxy wheat starches and their respective A‐ and B‐type starch granule fractions. Native starch isolated from four closely related soft wheat lines (normal, partial waxy, and full waxy) was modified through 1) substitution (propylene oxide analog) and 2) cross‐linking (phosphorus oxychloride) reactions to generate both types of modified starch products for each wheat line. Characterization of the unmodified starch fractions confirmed compositional differences among the cultivars and their respective granule types. In cross‐linking reactions, B‐type granules were slightly more reacted than A‐type granules for all cultivars, while the waxy starch generally exhibited higher reactivity compared with normal and partial waxy starches. For the substituted starches, no differences in reactivity were observed among the cultivars or between the two granule types.
Analysis of Headspace Volatiles of Corn Gluten Meal
Authors: Wu Y. V. , Payne‐Wahl K. L. , Vaughn S. F.
Published: June 2007

Corn gluten meal is the high‐protein fraction from wet milling of corn. Although protein, minerals, and fat compositions have been reported, minor components that cause unpleasant flavor and taste are not known. The objective of this study was to determine the compounds present in headspace of corn gluten meal and wet cake (dryer feed). A solid‐phase microextraction device with a polyacrylate coating was used to collect volatiles for 1 hr at 25 and 100°C above a stirred water slurry of corn gluten meal or wet cake. The absorbed compounds were desorbed onto the inlet injector of a gas chromatograph equipped with a mass selective detector. Compound identification was done using a Wiley library and confirmed by retention time of pure compounds in the gas chromatograph. Twenty‐nine compounds were identified. Knowledge concerning volatiles of corn gluten meal may lead to improvement of flavor and taste, and increased utilization of this material, produced over 1 million metric tons per year in the United States.
Relationships Between Gluten Rheological Properties and Hearth Loaf Characteristics
Authors: Tronsmo Kari M. , Magnus Ellen Merethe , Færgestad Ellen Mosleth , Schofield J. David
Published: June 2007

The rheological properties of fresh gluten in small amplitude oscillation in shear (SAOS) and creep recovery after short application of stress was related to the hearth breadbaking performance of wheat flours using the multivariate statistics partial least squares (PLS) regression. The picture was completed by dough mixing and extensional properties, flour protein size distribution determined by SE‐HPLC, and high molecular weight glutenin subunit (HMW‐GS) composition. The sample set comprised 20 wheat cultivars grown at two different levels of nitrogen fertilizer in one location. Flours yielding stiffer and more elastic glutens, with higher elastic and viscous moduli (G′ and G″) and lower tan δ values in SAOS, gave doughs that were better able to retain their shape during proving and baking, resulting in breads of high form ratios. Creep recovery measurements after short application of stress showed that glutens from flours of good breadmaking quality had high relative elastic recovery. The nitrogen fertilizer level affected the protein size distribution by an increase in monomeric proteins (gliadins), which gave glutens of higher tan δ and flatter bread loaves (lower form ratio).
Influence of Raw Materials and Processing Conditions on Spaghetti Hydration Kinetic During Cooking and Overcooking
Authors: Del Nobile M. A. , Fares C. , Conte A. , Martinez‐Navarrete N. , Mocci G. , La Notte E.
Published: June 2007

A study of the influence of raw materials and processing conditions on the hydration kinetic during cooking and overcooking of spaghetti is presented. Water sorption tests on commercially available spaghetti and on three different types of homemade spaghetti were run at 100°C. In particular, the weight, diameter, and length of spaghetti strands were monitored over time for ≈200 min. The spaghetti hydration process was quantitatively resolved into the controlling phenomena (i.e., water diffusion, macromolecular matrix relaxation kinetic, and residual deformation release kinetic) by fitting a novel mathematical model to the experimental data. The different behavior of spaghetti was analyzed for each of the phenomena involved during hydration. Results suggest that processing conditions highly influence the quality of spaghetti with respect to raw materials.
Properties of Starches from Near‐Isogenic Wheat Lines with Different Wx Protein Deficiencies
Authors: Mangalika Wickramasinghe Hetti Arachichige , Miura Hideho , Yamauchi Hiroaki , Noda Takahiro
Published: June 2007

To determine the effect of amylose content on the starch properties, the amylose content, pasting properties, swelling power, enzymatic digestibility, and thermal properties of partial and perfect waxy types along with their wild‐type parent were analyzed. As expected, amylose content decreases differently in response to the loss of each Wx gene, showing the least response to Wx‐A1a. Most of the characteristics, except the thermal properties of the amylose‐lipid complex in differential scanning calorimetry (DSC), differed significantly among the tested types. Furthermore, the breakdown, setback, and pasting temperatures from the Rapid Visco Analyser (RVA) and the enzymatic digestibility, swelling power, peak temperature, and enthalpy of starch gelatinization from DSC showed a correlation with the amylose content. The relationships between the peak viscosity from the RVA and the onset temperature of starch gelatinization determined by DSC with amylose content of the tested materials were not clear. Waxy starch, which has no amylose, showed a contrasting behavior in starch gelatinization compared with nonwaxy starches. Among the nonwaxy starches, lower setback, lower pasting temperature, higher enzyme digestibility, higher peak temperature, higher enthalpy of starch gelatinization, and higher swelling were generally associated with low amylose starches.