Breadmaking Quality Of Wheat Flour Research Articles

Application of Microbial Transglutaminase in Wheat Bread Industry: A Review

Bread as the main food all over the world is generally based on wheat flour due to its unique properties to form a three-dimensional gluten network. In fact, the quality of bread is influenced by wheat gluten quality and quantity. The quality of gluten protein is mainly defined based on its amino acids composition and bonding (covalent and non-covalent). Gluten protein quality is considered weak based on its essential amino acid content: lysine and threonine. Covalent crosslinks as the main factor in determining the integrity of the gluten network are also interrupted by the activity of proteolytic enzymes and reducing agents. Different treatments (physical, chemical and enzymatic) are used to alleviate these detrimental effects and improve the bread making quality of wheat flour. Given that, food industry is looking for using enzymes (respecting their specificity, ease of use and low risk of toxic products formation) microbial transglutaminase is an efficient option, considering its ability to introduce new crosslinks. This new crosslink formation can either improve gluten protein quality in damaged wheat flour or imitate the function of gluten protein in gluten free bread. The aim of this article is to review the application of microbial transglutaminase enzyme as an improving agent in wheat bread industry.

Efectos de la fertilización nitrogenada en la composición de las proteínas de la harina y la calidad de la masa en trigo cultivado en la provincia de La Pampa

Breadmaking quality of wheat flour (Triticum aestivum L.) depends not only on the genotype but also on the availability of nitrogen, and wheat protein composition is important for understanding the biochemical basis of wheat quality. The objective of this study was to evaluate the effect of nitrogen availability on flour protein fractions, to analyze their distribution and relationship with bakery quality. We worked with ACA 315 cultivar, where different application rates and timing of nitrogen nutrition were tested. Flour protein fraction composition was quantified following two protocols. Nitrogen application affected glutenin concentration and protein fraction composition favoring polymeric proteins and increasing polymeric/monomeric proteins ratio, however, increase of flour polymeric proteins did not resulted in improved rheological properties. The nitrogen added in this experiment in the differen experiments was not enough to obtain good quality bakery flours. Low protein values were obtained in grain, low gluten concentration and the dough had low W value and high P/L, being very tenacious and no very extensible. Due to low grain protein concentration farinograph parameters could not be interpreted since, under these conditions they are overestimated. These results show that not only genotypic genetic information, should be considered, also gene expression regulation in response to environmental factors, such as nitrogen availability. Therefore, genotype should continue to be studied, both at the level of variation allelic individual and in combination of different alleles of grain reserve proteins. It is also necessary to incorporate in future studies amount and timing of nitrogen application and other nutrients, such us S, in order to obtain better quality bakery flours in La Pampa province.

Effects of a late N fertiliser dose on storage protein composition and bread volume of two wheat varieties differing in quality

Wheat is an important source of energy and protein for humans all over the world and is mainly consumed in form of baked goods, for which a high baking quality is required. The main parameter for bread-making quality predictions of wheat flours is the grain protein concentration (GPC). Therefore, the GPC determines the value of the harvested wheat. Unfortunately, the GPC appears to be no longer an appropriate parameter for baking quality evaluation, given that, especially for high protein varieties, the correlation between GPC and bread volume is poor. A late N application is commonly used to increase GPC and enhance the bread-making quality of wheat flours. To minimise the environmental problems involved in the late use of N fertilisers, it is important to know how much N is necessary to achieve the desired effects. Therefore, in this study, the effects of two different doses of late N application on the GPC, as well as storage protein composition and bread volume were tested in two wheat varieties from different quality groups under field conditions in Germany. The findings of this experiment demonstrate that a low late N application appears to be sufficient to achieve a good baking quality of wheat flours. These results confirm the presumption that GPC is not a suitable parameter for bread-making quality predictions. As the relationships between the single storage protein fractions and bread volume were poor, it can be concluded that only the combined alterations within all gluten protein fractions explain the rise in bread volume.

Lab-on-a-Chip method uncertanties in determination of high-molecular-weight glutenin subunits

Polymeric wheat endosperm proteins, especially the high-molecular-weight glutenin subunits (HMW-GS), are probably the most interesting protein fraction giving the essential information about bread-making quality of wheat flour. A relatively new method that shows a great potential for a fast, reliable and automatable analysis of protein purity, sizing and quantification is microfluidic or Lab-on-a-Chip (LoaC) capillary electrophoresis. This work was aimed to explore the possibilities of implementation of LoaC method to analysis of protein samples isolated from a Serbian common wheat variety, emphasizing the steps that might bring uncertainties and affect reproducibility of obtained glutenin subunits quantitation results. A good resolution of protein bands in a molecular weight range of 14.0 to 220.0 kDa was achieved. The reproducibility of HMW-GS sizing and quantitation were good, with the average coefficient of variation values of 1.2% and 12.2%. The ratio of HMW-GS to low-molecular-weight glutenin subunits (LMW-GS) was about 20%. The investigation ruled out influences of the extract solution addition and the buffer addition steps of the applied method, as well as the individual chip influence on GS quantitation results. However, there was statistically significant difference between HMW-GS quantitation results of multi-step and one-step extraction procedures applied prior to glutenin subunits extraction step.

Combined effect of genetic and environmental factors on the accumulation of proteins in the wheat grain and their relationship to bread-making quality

Bread-making quality of wheat flour is largely determined by the accumulation, concentration and composition of the proteins in the grain, which are influenced by genetic (G) and environment (E) variation and their interactions. We have therefore evaluated the importance of G and E factors and their interactions in determining the accumulation and composition of the proteins in the wheat grain. The cultivar determined development time (CDDT), together with the amount and timing of N application, played a significant role in determining the accumulation and final composition of the wheat grain proteins, explaining 21–59% of the variation. At low temperature, N application both at spike formation and at anthesis explained the highest proportion of variation (36%) in the percentage of sodium dodecyl sulphate (SDS) unextractable polymers in the total amount of polymers (% UPP), while at high temperature CDDT contributed most to the variation in % UPP (20%). The largest contributor to variation in the amount of total SDS extractable proteins (TOTE) was N application at anthesis, both at low and high temperatures (12% and 36%, respectively). Thus, the climate should be considered in recommendations for improving the protein quality and thereby the bread-making quality of wheat.

Individual and interactive effects of genetic background and environmental conditions on amount and size distribution of polymeric proteins in wheat grain

Bread-making quality of wheat flour is influenced by wheat storage proteins. The percentage of sodium dodecyl sulphate (SDS)-unextracted polymeric proteins in total polymeric proteins (% UPP), as one important factors determining bread-making quality, is largely influenced by the individual and interactive effect of genetical background and environmental conditions. Four spring wheat cultivars were grown in green house. Two of the cultivars have high molecular weight glutenin subunits 5+10 while the other two have 2+12. Four different nitrogen regimes and two different temperature levels (distinguished as low and high temperature) were used. The results highlighted the importance of interactive influence of cultivars, nitrogen regimes and temperature levels for creating differences in the amount of % UPP during grain maturation period (GMP) and at maturity. The shift to end up with either high or low % UPP at maturity happened early during GMP (around 12 days after anthesis). Influences of cultivars on % UPP was found early during the GMP while influences of temperature and nitrogen regimes were seen much later during the GMP. The results will help in understanding the relationship between quality parameters of wheat flour and how these are influenced by different environmental and genetic factors.

Bread-making Quality of Wheat Flour Produced in Gifu Prefecture: Granule Size Prepared with Different Mills

Bread-making Quality of Wheat Flour Produced in Gifu Prefecture: Granule Size Prepared with Different Mills

Influence of micronutrients on rheological characteristics and bread-making quality of flour

Studies were carried out to see the influence of different iron and calcium salts along with some vitamins on the rheological characteristics and bread-making quality of wheat flour. Fortification with iron (30–90 ppm) from different sources showed a marginal increase in water absorption (2%). Calcium ranging between 800 and 1,600 ppm did not show any influence on the mixing properties of the dough. Except for ethylenediamine tetraacetic acid and calcium lactate, all other salts did not have any influence on the alveograph characteristics. The gelatinization temperature slightly increased by about 2–3°C and the cold paste viscosity increased from 468 to 524 BU. Addition of micronutrient premix containing ferrous sulphate, calcium carbonate and vitamins such as thiamine (thiamine hydrochloride), riboflavin, niacin (nicotinic acid) and folic acid at different levels showed a marginal effect on the rheological parameters. There was no significant influence of micronutrient premix on the objective and subjective evaluation of the breads, except for the crumb colour. Fortification with the vitamin–mineral premix did not affect the rheological parameters and bread-making quality of flour, even after storage.

Effect of Aphid Feeding on the Glutenin, Gliadin and Total Protein Contents of Wheat Flour

Plant sucking aphids cause both quantitative and qualitative yield losses in cereals; moreover aphid-transmitted viruses are responsible for other quantitative and qualitative damages, thus direct or indirect effects of aphid infection are in focus of interest. Bread-making quality of wheat flour is determined primarily by the protein content and composition, the gluten proteins (glutenins, gliadins) being the prime factors. Allelic composition of the gliadin- and glutenin loci as well as the absolute amount and/or the relative ratio of gliadins to glutenins are very important in dough making and in determining baking quality. Wheat plants were caged at the beginning of stem elongation. Cages were treated with 0.1% methyl parathion. One week later, the caged plants were artificially infected with 5 alata individuals of Metopolophium dirhodum, Diuraphis noxia, Sitobion avenae and Rhopalosiphum padi. Flour from grains originating from plants infected artificially with cereal aphids were analyzed for glutenin and gliadin and total protein content, using Size Exclusion HPLC. It was found that aphid infection had significant effect on the glutenin and gliadin content, the total protein content and the gliadin/glutenin ratio. Both the glutenin and gliadin content was significantly higher in the seeds harvested from aphid infected plants. However, the gliadin/glutenin ratio was significantly lower in wheat flour prepared from aphid infected plants than in those from uninfected control. The most significant decrease in gliadin/glutenin ratio was caused by M. dirhodum, D. noxia, S. avenae infection followed by R. padi at high-abundance and low-abundance, respectively. As the gliadin/glutenin ratio was significantly lower in flours made from aphid infected wheat seeds, it may be suggested that aphid feeding results in decreased bread making quality of wheat flour.

An approach for isolating high-molecular-weight glutenin subunit genes using monoclonal antibodies

High-molecular-weight glutenin subunits (HMW-GSs) play an important role in the breadmaking quality of wheat flour. In China, cultivars such as Triticum aestivum 'Xiaoyan No. 6' carrying the 1Bx14 and 1By15 glutenin subunits usually have attributes that result in high-quality bread and noodles. HMW-GS 1Bx14 and 1By15 were isolated by preparative sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and used as an antigen to immunize BALB/c mice. A resulting monoclonal antibody belonging to the IgG1 subclass was shown to bind to all HMW-GSs of Triticum aestivum cultivars, but did not bind to other storage proteins of wheat seeds in a Western blot analysis. After screening a complementary DNA expression library from immature seeds of 'Xiaoyan No. 6' using the monoclonal antibody, the HMW-GS 1By15 gene was isolated and fully sequenced. The deduced amino acid sequence showed an extra stretch of 15 amino acid repeats consisting of a hexapeptide and a nonapeptide in the repetitive domain of this y-type HMW subunit. Bacterial expression of a modified 1By15 gene, in which the coding sequence for the signal peptide was removed and a BamHI site eliminated, gave rise to a protein with mobility identical to that of HMW-GSs extracted from seeds of 'Xiaoyan No. 6' via SDS-PAGE. This approach for isolating genes using specific monoclonal antibody against HMW-GS genes is a good alternative to the extensively used polymerase chain reaction (PCR) technology based on sequence homology of HMW-GSs in wheat and its relatives.

Breadmaking stability of wheat flours: Relation between mixing properties and molecular weight distribution of polymeric glutenins

The environmental stability of breadmaking quality of wheat flours i.e. the absence of fluctuation across environments and genotype×environment interactions is as important as their performance in milling and baking. Many statistical approaches have been used to assess cultivar stability parameters across environments. Quality stability parameters were studied using a set of eleven bread wheat cultivars and five hybrid wheats grown in France at eight locations in two consecutive years. Three different statistical variances: ecovalence Wi, environmental variance S X i 2 and genotypic stability were used to assess the stability of quality parameters measured on wheat kernels at harvest, on the technological properties of their flours and on the molecular weight distribution of total endosperm proteins extracted using 2% SDS in phosphate buffer with sonication. Asymmetrical flow field-flow fractionation coupled with a multi-angle laser light scattering photometer allowed the molar masses of polymeric glutenins to be measured without size limits. Marked variation in the quality parameters was observed due to genetic and environmental effects. The three stability values calculated for protein content were not significantly correlated to the stability of the polymeric fraction, the bread loaf volume (LV) or the bread quality score (BQS). The three stability values of LV and BQS were significantly correlated to the stability of the weight-average (〈 M〉w) molecular weight of the polymeric fraction. Multiple regressions showed that 60–84% of the stability values of LV and BQS were explained by the stability of only few quality parameters among which the 〈 M〉w of polymers played the major role.

Effect of soybean addition on the rheological properties and breadmaking quality of wheat flour

AbstractThe effects of enzyme‐active full‐fat (EAFFSF), heat‐treated full‐fat (HTFFSF) and enzyme‐active defatted (EADSF) soy flours and commercial soy protein isolates (SPIs) on mixing properties and extensibility of dough, gluten formation, gas production and retention properties of dough and bread quality were studied. The soy products utilised in this study presented values of urease activity, nitrogen solubility index (NSI) and enthalpies of protein denaturation according to their previous heat processing. Soy products interfered in gluten formation, weakened dough strength and decreased dough gas retention capacity. Bread quality was negatively affected by soy product addition. The negative effects were exacerbated by an increase in soy/wheat ratio. Soybean protein state was identified as an important factor in determining dough and bread properties. Copyright © 2005 Society of Chemical Industry

Improvement of the breadmaking quality of wheat flour by the hyperthermophilic xylanase B from Thermotoga maritima

The study was carried out to investigate the effect of hyperthermophilic xylanase B (XynB) from Thermotoga maritima on the properties of wheat bread and its staling during storage. The presence of XynB in the dough led to improvements in the breadmaking quality (i.e. specific volume and crumb structure) and provided an anti-staling effect on breads compared to the control. Addition of XynB could cause ≈60% increase in specific volume in comparison with the control. By fitting the crumb firming kinetics during storage to the Avrami equation, it showed that XynB retarded the bread staling by reducing the initial crumb firmness and the firming process during storage. XynB hydrolyzed the isolated WU-AX faster than WE-AX under the ratio of wheat AX in wheat flour. Improvement of bread quality by XynB can partly be ascribed to the enzyme specificity.

Glutenin and gliadin contents of flour derived from wheat infested with different aphid species.

Aphid feeding in cereals results in both quantitative and qualitative yield losses; moreover aphid-transmitted viruses are responsible for other quantitative and qualitative damage so that direct or indirect effects of aphid infection are always of interest. At the beginning of stem elongation, wheat plants were caged regardless of the presence or absence of indigenous cereal aphids. Half of the caged plants were artificially infected with Diuraphis noxia. The number of D noxia and Rhopalosiphum padi individuals on plants destined for flour preparation was approximately 150 aphids per tiller at peak population. The number of Sitobion avenae individuals was ca 25 aphids per tiller. Bread-making quality of wheat flour is determined primarily by the protein content, the gluten proteins (gliadins, glutenins) being the prime factors. The absolute amounts and/or the relative proportion of gliadins and glutenins are very important in dough making and in determining baking quality. Flour from grains originating from plants infected naturally with cereal aphids indigenous to Hungary, and flour infected artificially with D noxia, were analysed for glutenin and gliadin content using size exclusion HPLC. It was found that aphid infection had a significant effect on the gliadin/glutenin ratio, which was significantly lower in wheat flour prepared from aphid-infected plants than in that from uninfected control. The most significant decrease in gliadin/glutenin ratio was caused by D noxia infection, followed by R padi and then S avenae. As the gliadin/glutenin ratio was significantly lower in flour made from aphid-infected wheat seeds, it can be supposed that aphid feeding results in decreased bread making quality of wheat flour.

Expression of a novel high-molecular-weight glutenin subunit gene in transgenic wheat.

High-molecular-weight glutenin subunits (HMW-GS), one class of seed storage proteins, are important determinants of the bread-making quality of wheat flour. To change the amount and composition of these proteins via genetic engineering, a gene encoding a novel hybrid subunit under the control of native HMW-GS regulatory sequences was inserted into wheat. Of 26 independent transgenic lines identified by bialaphos selection, 18 expressed the cotransformed hybrid HMW-GS gene in their seed. The hybrid subunit accumulated to levels comparable to those of the native HMW-GS. These results show that a native HMW-GS gene promoter can be used to obtain high levels of expression of seed storage and, potentially, other proteins in transgenic wheat endosperm. Transgene expression was stable for at least three seed generations in the majority of lines. These experiments demonstrate the feasibility of constructing wheat plants with novel seed protein compositions.

Effect of arabinoxylans on bread-making quality of wheat flours

Two highly purified arabinoxylan preparations of different molecular weight (HMW, [η] = 5.48 dl/g and LMW, [η] = 3.69 dl/g) were used to study the effect of these water-soluble polysaccharides on the bread-making quality of two wheat flours: a Canada western red spring (CWRS) composite sample and a Canada prairie spring (CPS), cv. HY 368. Both preparations significantly increased the farinograph water absorption and the dough development time for the two flours; the HMW arabinoxylans exerted significantly ( P < 0.01) greater effects than the LMW preparation. The HMW arabinoxylans maximally improved the loaf volume of CWRS and CPS breads at a level of 0.5% (w/w) supplementation. The LMW arabinoxylans maximally increased the loaf volume of CWRS and CPS breads at 0.7 and 1.1% (w/w), respectively. Breads containing HMW arabinoxylans retained significantly ( P < 0.01) more water than the breads with LMW polymers at 0.5-0.9% (w/w) supplementation levels. Because of their higher moisture content the arabinoxylan-fortified breads exhibited a greater rate of starch retrogradation as assessed by calorimetry. Nevertheless, these breads had softer breadcrumbs than the controls; breads fortified (0.3-0.9% w/w) with HMW arabinoxylans were significantly ( P < 0.01) less firm than those with LMW polymers over the 7-day storage period.

Immunochemical identification of LMW subunits of glutenin associated with bread-making quality of wheat flours

A murine monoclonal antibody (IFRN 0067), one of a library developed against prolamin fractions fromTriticum aestivum, has been characterised using a combination of immunoassay and immunoblotting techniques. The antibody was specific for two glutenin polypeptides which appeared by 2-dimensional electrophoresis to belong to the B group of LMW subunits. From results of antibody-binding studies with material extracted from genetic stocks, it was deduced that the target polypeptides were encoded on the short arm of chromosome 1D. The antibody was used in an immunoassay of bread wheats with a range of anticipated baking scores and for flours of known baking performance. Significant correlations were found between immunoassay and test-bake results. Indeed, correlation of IFRN 0067 binding with loaf volume was equal or better than that provided by alveograph parameters. The results provide evidence that LMW subunits contribute to the bread-making properties of wheat glutenin, as identified by the use of immunological techniques. The use of particular monoclonal antibodies, such as IFRN 0067, in the further development of simple, rapid diagnostic tests for flour quality predictions is discussed.

The effect of laboratory and commercial milling on lipids and other physicochemical factors affecting the breadmaking quality of wheat flour

The volumes of loaves made by mechanical dough development from two commercially milled and eight laboratory-milled flours were significantly (P

Dough quality of biotypes of eleven Australian wheat cultivars that differ in high-molecular-weight glutenin subunit composition

The content and composition of gluten proteins are the major factors determining the breadmaking quality of wheat flour. Although gluten is a complex mixture of many proteins, one group (called the HMW subunits of glutenin) is particularly important in determining dough strength. Technologies for the genetic transformation of wheat (including gene editing) are now well established and have been used to explore the role of individual gluten proteins in determining quality and to demonstrate that improvements can be made by manipulating protein composition. However, these have not been used to develop lines for commercial production due to regulatory restrictions.