Protein Content Of Wheat Flour Research Articles

Brewers' spent grain from three styles of craft beer: Characterization and their rheological effects on wheat flour dough

Background and Objectives To use the diversity of Brewers' spent grain (BSG) from craft beer as an ingredient of functional bread, it is required to characterize and know their effects on dough and breads. The present work investigated the physicochemical characteristics of BSG, and the farinograph effects of wheat flour substituted by Baltic Porter (BP), India Pale Ale (IPA), and Weiss (W) BSGs in amounts of 10%. Results were used for predicting the end-use quality and bread-making performance of wheat flour and wheat flour-BSG blends. Reliability of prediction was verified by a baking test. Findings BSG from barley malt beers BP and IPA were higher in protein and lower in carbohydrate content than barley/wheat malt W BSG. The heterogeneity of ground and sieved BSG was shown by pictures taken from microscopy images of endosperm, husk, and husk/endosperm particles varying in quantities, forms, and size. Water absorption of dough was slightly affected by W, while all dough containing BSG had the development time and stability lowered when compared with the control. Conclusions The prediction of bread-making performance showed that, while control and BP reached the “bread quality” range, W and IPA scored under “bread quality” range because of their lower stability. On the baking test, specific volume of control, BP, and IPA breads were in agreement with their prediction. W bread, however, in disagreement with prediction, presented specific volume closer to the predicted as “bread quality” BP bread. Significance and Novelty Beer style affected BSG composition and farinograph behavior of wheat flour dough-BSG blends, with the stability being the determinant parameter on defining their end-use and bread-making quality. Significant correlations of lipid content in BSG were positive for development time and negative for tolerance index. There is no standard farinograph behavior of wheat flour-BSG blends, with these effects being governed, beyond BSG composition, by protein content of wheat flour.

Pasting properties of high-amylose wheat in conventional and high-temperature Rapid Visco Analyzer: Molecular contribution of starch and gluten proteins

The popularity of high-amylose cultivars of main crops (e.g., high-amylose wheat, HAW) has been increasing because of their unique functional properties and enhanced nutritional values. In the current study, we employed the high-temperature Rapid Visco-Analyzer (HTRVA) to evaluate the performance of HAW flours and starches with an extensive range of amylose contents under high-temperature processing. The pasting parameters, total setback viscosity (TSV) and final viscosity (FV) from HTRVA, did not significantly correlate ( p > 0.05) with those from conventional RVA. The results indicate that conventional RVA could not robustly predict the pasting behaviours of HAW ingredients at high-temperature processing (partially due to different extent of starch disruption and leaching). The amylose content by iodine colorimetry method was not a good indicator of the cooling and retrogradation process of HAW flour and starch after high-temperature heating, with low R 2 values of the linear regression of TSV and FV on amylose content. However, TSV and FV of HAW flours as analysed by HTRVA negatively correlate ( p < 0.01) with wheat flour protein content, as well as with the abundance of glutenin (low molecular weight subunit, p < 0.05) as identified by a SWATH-MS (Sequential Window Acquisition of all Theoretical Mass Spectra) proteomics method. The protein attributes could contribute to restricting both swelling of granules during heating and the reassociation of starch polymers during cooling. Amylose (AM) and amylopectin (AP) fine structural features also regulate pasting behaviours. In particular, longer amylopectin outer chains promote peak viscosity, while larger amylose (whole) molecules have the opposite effect. This study presents new insights into the molecular basis for the pasting behaviours of HAW in conventional and high-temperature RVA. • High-temperature RVA profiles were compared to conventional RVA profiles. • High heating temperature reduced holding strength and final viscosity. • Peak viscosity was increased by longer AP outer chains but reduced by larger AM. • Total protein did not correlate with high temperature or conventional RVA parameters. • Detailed glutenin profiles (e.g., LMW-GS) show correlations with pasting parameters.

Effect of &lt;i&gt;Tribolium castaneum&lt;/i&gt; (Herbst) (Coleoptera: Tenebrionidae) Infestation on Wheat Flour Quality at Different Temperatures

Tribolium castaneum is one of the most destructive insects infesting cereals and their products worldwide. The quality changes of wheat flour infested by initial 0 (as a control), 2, 4, 6, and 8 adults of T. castaneum in 500 g wheat flour were investigated at 15, 25, and 30°C after different storage periods. The quality of wheat flour changed little during 150 d storage at 15°C, but it significantly decreased with increasing initial insect density and storage time during 150 d storage at 25 and 30°C. The moisture content, fatty acid value, falling number, and protein content of wheat flour were 12.21±0.19%, 190.08±3.51 mg KOH (100 g)-1, 208.67±7.23 s, and 14.25±0.02% after 30 d storage at 30°C, respectively. The wet gluten content and dry gluten content of wheat flour could not be detected after 90 d storage at 25 and 30°C. These results provide useful information for maintaining wheat flour quality.

Evaluation of baking conditions for frozen doughs

The baking performance of fresh, non-fermented, pre-fermented and pre-rested doughs were investigated using different types of flours. Effect of protein content in wheat flour and effect of oat and barley supplementation on wheat dough and baked bread was evaluated. Effect of mixing speed, yeast concentration and two different proofing methods were also studied. Wheat flour with higher protein content gave a higher volume and specific volume. The substitution of wheat flour with increasing concentrations of oat and barley flour progressively decreased loaf and specific volume significantly. Prolonging the proofing time after thawing resulted in a good bread quality whereas high mixing speed did not affect the bread quality. The operating conditions for the proofing step were at 35 °C temperature and 80% relative humidity for 30 min. Higher concentration of baking yeast results in low quality crust in baked bread. Yeast concentration of 1.3% showed the best option for bread preparation, at which the bread moisture content was the highest. The results also showed that wheat flour with 13.3% protein content yielded higher volume than bread made from 10% protein content. The dough was stored at − 20 °C and the baking conditions were at 215 °C temperature for 25 min. Sensory studies did not yield significant variation in different bread preparations. The pre-rested frozen dough, gave the best baked bread compared to the pre-fermented and non-fermented breads.

A rapid classification of wheat flour protein content using artificial neural network model based on bioelectrical properties

A conventional technique of protein analysis is laborious and costly. One rapid method used to estimate protein content is near infrared spectroscopy (NIRS), but the cost is relatively expensive. Therefore, it is necessary to find a cheaper alternative measurement such as measuring the bioelectrical properties. This preliminary study is a new rapid method for classified modeling of wheat flour protein content based on the bioelectrical properties. A backpropagation artificial neural network (ANN) was developed to classify the protein content of wheat flour. ANN input were bioelectrical properties, namely capacitance, and resistance and output was a type of the flour, namely hard, medium and soft flour. The result showed that the ANN model could classify the various type of flour. The best ANN model produces a mean square error (MSE) and regression correlation (R) of 0.0399 and 0.9774 respectively. This ANN model could classify the protein content of wheat flour based on the bioelectrical properties and have the potential to be used as a basic instrument to estimate the protein content.

Quantification of protein in wheat using near infrared hyperspectral imaging: Performance comparison with conventional near infrared spectroscopy

Hyperspectral imaging is a powerful technique that combines the advantages of near infrared spectroscopy and imaging technologies. Most hyperspectral imaging studies focus on qualitative analysis, but there is growing interest in using such technique for the quantitative analysis of agro-food products in order to use them as universal tools. The overall objective of this study was to compare the performance of a hyperspectral imaging instrument with a classical near infrared instrument for predicting chemical composition. The determination of the protein content of wheat flour was selected as example. Spectra acquisition was made in individual sealed cells using two classical near infrared instruments (NIR-DS and NIR-Perstop) and a near infrared hyperspectral line-scan camera (NIR-HSI). In the latter, they were also acquired in open cells in order to study the possibility of accelerating the measurement process. Calibration models were developed using partial least squares for the full wavelength range of each individual instrument and for the common range between instruments (1120–2424 nm). The partial least squares models were validated using the “leave-one-out” cross-validation procedure and an independent validation set. The results showed that the NIR-HSI system worked as well as the classical near infrared spectrometers when a common wavelength range was used, with an r2 of 0.99 for all instruments and Root Mean Square Error in Prediction (RMSEP) values of 0.15% for NIR-HSI and NIR-DS and 0.16% for NIR-Perstop. The high residual predictive deviation values obtained (8.08 for NIR-DS, 7.92 for NIR-HSI, and 7.56 for NIR-Perstop) demonstrate the precision of the models built. In addition, the prediction performance with open cells was almost identical to that obtained with sealed cells.

Differential effects of a post-anthesis fertilizer regimen on the wheat flour proteome determined by quantitative 2-DE

BackgroundMineral nutrition during wheat grain development has large effects on wheat flour protein content and composition, which in turn affect flour quality and immunogenic potential for a commodity of great economic value. However, it has been difficult to define the precise effects of mineral nutrition on protein composition because of the complexity of the wheat flour proteome. Recent improvements in the identification of flour proteins by tandem mass spectrometry (MS/MS) and the availability of a comprehensive proteome map of flour from the US wheat Butte 86 now make it possible to document changes in the proportions of individual flour proteins that result from the application of mineral nutrition.ResultsPlants of Triticum aestivum 'Butte 86' were grown with or without post-anthesis fertilization (PAF) and quantitative 2-dimensional gel electrophoresis (2-DE) was used to analyze protein composition of the resulting flour. Significant changes in the proportions of 54 unique proteins were observed as a result of the treatment. Most omega-gliadins, high molecular weight glutenin subunits (HMW-GS) and serpins as well as some alpha-gliadins increased in proportion with PAF. In contrast, alpha-amylase/protease inhibitors, farinins, purinins and puroindolines decreased in proportion. Decreases were also observed in several low molecular weight glutenin subunits (LMW-GS), globulins, defense proteins and enzymes. The ratio of HMW-GS to LMW-GS in the flour increased from 0.61 to 0.95 and the ratio of gliadins to glutenins increased from 1.02 to 1.30 with PAF. Because flour protein content doubled with PAF from 7 to 14%, most protein types actually increased in absolute amount (μg/mg flour protein). Data further suggest that flour proteins change with PAF according to their content of sulfur-containing amino acids Cys + Met.ConclusionsA 2-DE approach revealed changes in the wheat flour proteome due to PAF that are important for flour quality and immunogenic potential. The work forms a baseline for further studies of the effects of environmental variables on flour protein composition and provides clues about the regulation of specific flour protein genes. The study also is important for identifying targets for breeding programs and biotechnology efforts aimed at improving flour quality.

Influence of Proteins on the Mechanical Properties of Agro‐Based Materials

AbstractSummary: A new biodegradable thermoplastic material based on a wheat flour by‐product has been developed. The influence of protein content in wheat flour on the mechanical properties of the material has been investigated. For protein content between 4% and 10%, no influence of the protein content was evidenced, whereas beyond 10% w/w of proteins in the wheat flour, the mechanical properties of agro‐based materials decrease, thus confirming the advantage of using a wheat flour by‐product (i.e. with protein content below 8% w/w).

Influence of nitrogen fertilizer application rate on winter wheat (Triticum aestivum L.) flour quality and Chinese noodle quality

AbstractBACKGROUND: Understanding wheat flour noodle quality responses to N management will improve the quality of recommendations made to growers for specific end‐uses. Two winter wheat cultivars, with six N rates, planted during the course of a 2‐year experiment were used to determine the effect of N application rate on Chinese white noodle quality.RESULTS: Wheat flour protein content, development time (DT) and stability time (ST) increased with N application rate, maximal at 360 kg N ha−1 and decreasing thereafter. When the N fertilizer application rate changed from 0 to 270 or 360 kg N ha−1, redness (a*) and yellowness (b*) of both flour and noodle increased, while brightness (L*) decreased. The hardness and chewiness of cooked noodles improved at lower N application rate and degenerated at higher N rate.CONCLUSION: A low rate of N fertilizer application (from 0 to 270 kg N ha−1) improved flour quality. Flour protein content and protein quality parameters displayed a significant negative correlation with brightness (L*) values. Generally, high flour protein content and protein quality, as well as good noodle texture, could be achieved by topdressing N fertilizer (in the range 270–360 kg N ha−1). Copyright © 2009 Society of Chemical Industry

Wheat flour protein content and water absorption analysis in a doubled haploid population

A wheat×maize induced doubled haploid population that segregates at the Awned locus for awned and awnless phenotypes were studied at two field sites using a genetic linkage map. Interval QTL analysis indicated that significant QTLs for wheat flour water absorption and protein content were located on a linkage group associated with the morphological marker, awns. The QTL peak for flour water absorption was located at the Awned locus (B1, 5AL), whilst the QTL peak for protein content was located nearby, 10.1 cm away from the Awned locus. The locations of those QTL were confirmed by analysing data from two independent field trials conducted under different environment conditions. The QTL identified for water absorption controlled 12% and 11% of the observed variance at the two field trials, whilst for flour protein content the QTL explained 7% and 19% of the variance respectively. Variance component analysis indicated that the QTL for water absorption controlled approximately 14.8–25.0% and 13.6–23% of the genetic variance at the two sites studied (Roma and Jimbour) whilst the QTL for protein content explained between 12.8% and 30.4% of the genetic variance at Roma and 34.7–82.6% at Jimbour. Cross-site analysis with composite interval mapping approach resulted in significant LOD values of 6.12 and 9.94 for water absorption and protein content, respectively. The QTL for water absorption was independent from the hardness locus.

The near Infrared Window—Glass or Quartz? A Study in Precision

All near infrared instruments are equipped with a “window” to protect the detectors from the atmosphere. Many types of sample cells are also fitted with a window between the sample surface and the detector. These windows may be composed of special optical glass or quartz. This paper describes variability of wheat flour spectra when using a series of glass and quartz windows. Differences among the windows of both glass and quartz exhibited differences of up to respectively 40% and 14% in the spectral data when they were used in the development of calibration models for the prediction of protein content in wheat flour. The differences among the windows did not affect the precision of spectral data when the same window was used for replicate testing, but induced absolute biases of up to over 3% (glass) and 1% (quartz) to the predicted protein results. Biases could be countered by use of derivatives or by combining spectral data from flours by using the different windows in the development of the calibration models. An anomaly was noted in the flour spectra obtained using quartz window number 4. The anomaly was found to cause significant biases in the prediction of protein content. The biases could be removed if the calibration model was developed using a wavelength range that avoided the anomaly.

Synergistic and Additive Effects of Three High Molecular Weight Glutenin Subunit Loci. II. Effects on Wheat Dough Functionality and End‐Use Quality

ABSTRACTUnderstanding the relationship between basic and applied rheological parameters and the contribution of wheat flour protein content and composition in defining these parameters requires information on the roles of individual flour protein components. The high molecular weight glutenin subunit (HMW‐GS) proteins are major contributors to dough strength and stability. This study focused on eight homozygous wheat lines derived from the bread wheat cvs. Olympic and Gabo with systematic deletions at each of three HMW‐GS encoding gene loci, Glu‐A1, Glu‐B1, and Glu‐D1. Flour protein levels were adjusted to a constant 9% by adding starch. Functionality of the flours was characterized by small‐scale methods (2‐g mixograph, microextension tester). End‐use quality was evaluated by 2‐g microbaking and 10‐g noodle‐making procedures. In this sample set, the Glu‐D1 HMW‐GS (5+10) made a significantly larger contribution to dough properties than HMW‐GS coded by Glu‐B1 (17+18), while subunit 1 coded by Glu‐A1 made the smallest contribution to functionality. These differences remained after removing variations in glutenin‐to‐gliadin ratio. Correlations showed that both basic rheological characteristics and protein size distributions of these flours were good predictors of several applied rheological and end‐use quality tests.

Effect of safflower protein isolates on cookie characteristics

SummarySafflower protein isolates prepared by micellization (MP) and isoelectric precipitation (IP) were incorporated into sugar cookies. A commercial soybean protein isolate was used as reference. The amount of protein isolate added was that needed to increase the protein content of wheat flour by 20, 40 and 60%. Physical and sensory properties of the products were not significantly (P &gt; 0.05) affected by fortification with safflower protein prepared by MP, whereas some deterioration of these properties was observed when IP and soybean isolates were used.

VISCOSITY AND PICKUP OF A FISH AND CHIP BATTER: DETERMINANTS OF VARIATION

ABSTRACTRelationship between viscosity and pickup (percent coating weight) of a fish and chip batter was examined with respect to the following parameters: (1) protein content of wheat flour used, (2) batter temperature, and (3) batter holding time. Results obtained indicated that a statistically significant (P 0.001) correlation existed between viscosity and: (1) wheat flour protein content (r= 0.96), (2) percent pickup (r= 0.90), and (3) batter temperature (r=−0.62). Results also indicated that protein content of the wheat flour ingredient and batter temperature may be used as indicators of batter viscosity and, subsequently, percent pickup in the operation of battering portion‐controlled codfish fillets.

Influence of irrigation and nitrogen fertilization on the amino acid composition of spring wheat

Sprinkler irrigation on clay soils in southern Finland decreased the protein content of spring wheat flour in five field experiments in the years 1967—70, by 16 ± 4 per cent on an average. The amino acid composition, however, was improved, because the proportion of lysine was increased by 6 ± 4 %. Accordingly, the content of lysine in flour was decreased by irrigation only by 10 ± 5 %. An increase of fertilizer nitrogen from 68 to 144 kg/ha increased the protein content of wheat flour by 19 ± 5 %, but the proportion of lysine in the amino acid composition decreased by 9 ± 4 %. Therefore, the lysine content in flour was increased by nitrogen fertilization only by 8 ± 5 %. It seemed as if urea and ammonium nitrate limestone would have had about the same effect on the quantity and quality of wheat protein. As a consequence of the reversed influences of irrigation and nitrogen fertilization on the wheat protein it was possible, by means of irrigation and an additional nitrogen fertilization, to produce 65 per cent higher grain yields without any noteworthy changes in the contents of protein or amino acids.

INHERITANCE OF FLOUR PROTEIN CONTENT IN A SELKIRK X GABO CROSS

T h e inheritance of grain protein content has been \videly studied with the objective of improving the balcing characteristics of n ~ h e a t flour. Many of the earlier studies indicated that thc environmental influence was fully as important as genetic factors in dctcrn~ining protein content (Stuber et al., 1962). Recently, Davis et a/. (1961) reported protein heritability estimates which varied f rom 54 to 69% in crosses between four soft winter varieties. For crosses between soft and hard winter varieties, Haunold et al. (1962) and Stuber et al. (1962) obtained heritability values of 56% and 83%, respectively. In the above studies the F, protein distributions resembled normal distributions and there was no evidence of a preponderance of dominant genes fo r either high o r low grain protein. Based on the regression of F, and F, on line values, Lebsoclc et al. (1961) calculated heritabilities of 37% and 70/,, respectively, for grain protein content in a l ~ a r d spring wheat cross. T h e reason for the widely different heritabilities was attributed to the influence of environment on protein content. I n their experiment the F, protein mean approached that of the low protein parent n~h i l e the F, line values werc distributed nornlally over the range represented by the parents. N o reports o n the inheritance of the protein content in wheat flour have been found in the literature. T h e purpose of the present investigation was to study the inheritance of flour protein content in a cross between two hard spring wheat varieties. Single plant populations of the PI, P,, F,, Fc, F3, BCl, and BC, generations nrcre used to estimate heritability, number of genes, and the genetic advance possiblc by selection. Intergeneration relations and heritability were also calculated fro111 a series of F:,, F.,, and F, families obtained f rom the Sellcirlc x Gabo cross.