Wheat Gluten Proteins Research Articles

Study on moisture migration mechanism of dough during subfreezing storage

AbstractBackground and ObjectivesThe objective of this study was to investigate the effects of subfreezing storage on gluten protein denaturation and water retention. On this basis, the surface hydrophobicity, secondary structure, thermal stability, microstructure, and moisture distribution of gluten protein were measured.FindingsThe results showed that at the end of storage, the hydrophobicity indexes of wheat gluten proteins (−9°C and −12°C) stored under subfreezing conditions were significantly lower than those stored at 4°C and slightly lower than those stored at −18°C. The secondary structure stability of wheat gluten stored at −18°C was similar. P21 stored at −18°C was significantly higher than those stored at 4°C and showed an upward trend. The quality of the dough was similar to those stored at −18°C.ConclusionsThe deformation and water retention of gluten during subfreezing storage are similar to those stored at −18°C.Significance and NoveltyThe changes in dough moisture and gluten protein structure during frozen storage at different freezing temperatures were explored to provide a theoretical basis for the application of subfrozen storage in the frozen flour products industry.

Hydrophilic co-assembly of wheat gluten proteins and wheat bran cellulose improving the bioavailability of curcumin

Low-cost wheat by-products have been modified to become an effective delivery system for curcumin. Wheat bran cellulose (WBC) and wheat gluten proteins (WPs) were co-assembled by a pH cycle and addition of sodium tripolyphosphate (STP). Fluorescence spectroscopy and zeta-potential evidenced that the embedding of WBC into the WPs favored the formation composites a relative unfolding state. Modifying the nanocomposite with STP lowered the Dh and PDI of the co-assembled structure. The nanocomplexes had a typical core–shell structure according to TEM characterization, where proteins aggregate to form a hydrophobic core and the hydrophilic WBC and STP crosslinked to form the shell. To improve the bioavailability of curcumin, it was encapsulated in WWBCs composites by participating in their structural co-assembly. In vitro simulated gastrointestinal digestion experiments showed that the curcumin encapsulated in WWBCs possessed gastrointestinal slow and controlled release function, with a final release of curcumin of 77.8 ± 2.3 %.

Chemistry of wheat gluten proteins: Quantitative composition

AbstractBackground and ObjectivesWheat is essential to secure nutrition for the world's population. Its unique processing properties are largely determined by gluten protein content and composition.FindingsGluten proteins are subdivided into gluten protein types, α‐, γ‐, ω1,2‐, and ω5‐gliadins and high‐molecular‐weight glutenin subunits and low‐molecular‐weight glutenin subunits. The overall content and relative proportions of these types vary considerably depending on different genetic and environmental factors and mutual interactions.ConclusionThis review summarizes the latest developments related to the chemistry of gluten and how species and variety, as well as soil type, weather conditions, atmospheric CO2 concentration, diseases, and fertilization with nitrogen, sulfur, phosphorus, potassium, and other minerals affect wheat gluten protein composition.Significance and NoveltySignificant progress has been made to study the effect of different factors on gluten composition. However, comparisons between studies are almost impossible, because of the huge variability in experimental setups, environmental conditions and varieties studied. This calls for a need to develop common guidelines on how to set up experiments, on which parameters to investigate and on which procedure to use to improve comparability and reproducibility of the results.

Hypoallergenic Wheat Line (1BS-18H) Lacking ω5-Gliadin Induces Oral Tolerance to Wheat Gluten Proteins in a Rat Model of Wheat Allergy.

The early ingestion of food can prevent the onset of food allergy related to inducing oral tolerance (OT). We developed the Hokushin wheat line as a hypoallergenic wheat (1BS-18H) lacking ω5-gliadin, a major allergen of wheat-dependent exercise-induced anaphylaxis (WDEIA). The 1BS-18H wheat had lower ability of sensitization for ω5-gliadin compared with Hokushin wheat. Here, we evaluated the induction of OT to gluten and ω5-gliadin by the early consecutive ingestion of 1BS-18H gluten using a rat model of wheat allergy. Rats were subcutaneously immunized with commercial gluten or native ω5-gliadin following the daily oral administration of gluten. The daily oral administration of 1BS-18H gluten for 5 days before immunization suppressed the increase in gluten- or ω5-gliadin-specific IgE and IgG1 antibodies induced by immunization to a level similar to Hokushin gluten. Intravenous challenge with gluten or ω5-gliadin did not decrease the rectal temperature in rats with OT induced by 1BS-18H or Hokushin gluten, although it was decreased in non-OT rats. In conclusion, the early consecutive ingestion of 1BS-18H wheat before sensitization induced OT to gluten and ω5-gliadin. These findings support the benefit of 1BS-18H wheat to prevent wheat allergy including WDEIA by consecutive ingestion in humans.

The effects of high molecular weight glutenin subunits in wheat flours on soft- and hard-dough biscuit products quality

High molecular weight glutenin subunits (HMW-GS) are the main wheat gluten proteins in flour that determine the viscoelastic properties of various types of dough. In this study, the effects of HMW-GS on various quality characteristics of certain soft wheat biscuit products were investigated. Results of the study showed that subunit 5x + 10y in the Glu-D1 locus increased the gluten strength of a flour and, consequently, negatively affected the physical and sensory properties of the resulting soft-dough biscuit products made with that flour. While product results suggested that the wheat genotypes carrying the allele 1 in Glu-A1 should be selected with care, in terms of biscuit sensory properties, the combination of the null allele in Glu-A1 and subunits 7 in Glu-B1 and 2x + 12y in Glu-D1 can lead to increased success of wheat breeding programs aimed at flours preferred for soft-dough biscuit products. For hard-dough biscuit products, subunit 2* can be used as a marker, in order to eliminate those soft wheat lines having too-high gluten strength. The combinations of HMW-GS 1, 7x + 9y, and 5x + 10y, along with the 1B/1R wheat-rye translocation, were considered to result in flours for production of hard-dough group biscuits. This study suggested that the most suitable HMW-GS combinations of wheat genotypes for soft- and hard-dough biscuit products. Those combinations considering wheat-rye translocation could be used for selection, or elimination, purposes in breeding programs targeting soft wheat varieties for specific baked products.

Chemistry of wheat gluten proteins: Qualitative composition

AbstractBackground and ObjectivesWheat gluten proteins make up one of the most complex protein aggregates in nature. Their qualitative and quantitative composition is determined by genetic and environmental factors as well as technological processes.FindingsGluten proteins comprise ω5‐, ω1,2‐, α‐, and γ‐gliadins as well as high‐molecular‐weight glutenin subunits (HMW‐GS) and low‐molecular‐weight (LMW) GS. About 50% of gluten proteins are monomeric gliadins with MWs from 28,000 to 55,000, while about 15% are present as disulfide‐linked oligomeric proteins with MWs between 70,000 and 700,000, called HMW‐gliadins. The remaining 35% are disulfide‐linked polymeric glutenins with MWs from 700,000 to more than 10 million. Intrachain disulfide bonds, present in all types except ω‐gliadins, stabilize the three‐dimensional structure, while interchain disulfide bonds, mainly linking HMW‐GS and LMW‐GS, generate oligomers and polymers.ConclusionsIn this review, we provide an updated and detailed insight into the chemistry of wheat gluten proteins with a focus on the qualitative composition.Significance and NoveltyAn enhanced understanding of gluten protein structure and how it is affected will be essential to select and breed more resilient wheat varieties with favorable processing properties to help ensure nutrition and food security worldwide.

Apparent digestibility coefficients of selected protein ingredients for juvenile Totoaba macdonaldi

AbstractTwo feeding trials were performed to evaluate the apparent digestibility coefficients (ADCs) of dry matter, protein, and amino acids of three animal‐origin and four plant‐origin ingredients in Totoaba macdonaldi. In the first feeding trial, the animal‐origin ingredients were evaluated using totoaba juveniles with an initial weight of 529.7 ± 104.2 g, and for the second feeding trial 745.9 ± 210.6 g. Evaluated ingredients were: poultry by‐product meal, meat and bone meal, feather meal (FM), soy protein concentrate, soybean meal (SBM), corn gluten (CG), and wheat gluten (WG). Each experimental ingredient was evaluated in triplicate. ADCs of dry matter ranged from 35.9% for FM to 67.9% for poultry by‐product, while the protein ADCs values ranged from 41.7% for CG to 83.2% for poultry by‐product. Fish meal ADC (79.6%) was similar to poultry by‐product but significantly higher than WG and soy protein concentrate (72.5% and 72.6%, respectively). The ADCs for lysine were significantly higher for WG, sardine meal, poultry by‐product, and SMB (94.5%, 79.8%, 79.4%, and 79.4%, respectively). Based on the results from the present study, poultry by‐product, WG, and soy protein concentrate are the most promising alternative ingredients (i.e., to the fishmeal) for the formulation of totoaba grow‐out feeds.

Zöliakie: vom Symptom zur Diagnose

Celiac disease is an IgA-mediated intolerance to the gliadin fraction of wheat gluten protein. Grains that contain gluten include wheat, rye, barley, and emmer. About 1% of the worldʼs population is affected by celiac disease. Patients can present with both gastrointestinal and extraintestinal manifestations of the disease. A total of 57 celiac patients from our hospital participated in a questionnaire study, which was dedicated to the topics of symptomatology, diagnosis, and quality of life. Data were analyzed with descriptive statistics and will be used to generate hypotheses for further studies.

Pediococcus acidilactici Strain Alleviates Gluten-Induced Food Allergy and Regulates Gut Microbiota in Mice.

Wheat flour, the most important source of food globally, is also one of the most common causative agents of food allergy. Wheat gluten protein, which accounts for 80% of the total wheat protein, is a major determinant of important wheat-related disorders. In this study, the effects of Pediococcus acidilactici XZ31 against gluten-induced allergy were investigated in a mouse model. The oral administration of P. acidilactici XZ31 attenuated clinical and intestinal allergic responses in allergic mice. Further results showed that P. acidilactici XZ31 regulated Th1/Th2 immune balance toward Th1 polarization, which subsequently induced a reduction in gluten-specific IgE production. We also found that P. acidilactici XZ31 modulated gut microbiota homeostasis by balancing the Firmicutes/Bacteroidetes ratio and increasing bacterial diversity and the abundance of butyrate-producing bacteria. Specifically, the abundance of Firmicutes and Erysipelotrichaceae is positively correlated with concentrations of gluten-specific IgE and may act as a fecal biomarker for diagnosis. The evidence for the role of P. acidilactici XZ31 in alleviating gluten-induced allergic responses sheds light on the application of P. acidilactici XZ31 in treating wheat allergy.

Beneficial Role of Microbial Transglutaminase in the Pathogenetic Mechanisms of Coeliac Disease.

Coeliac disease (CD) is caused by immunological intolerance to wheat gluten and related proteins of rye and barley. Consequently, gluten-free (GF) products have been developed but technological implementation is required to improve their intrinsic rheological properties. One alternative for increasing the functional properties of GF foodstuff is the incorporation of microbial transglutaminase (mTG), which allows for the cross-linking of proteins that can substitute for the gluten network in the bakery industry. mTG has been, however, suggested to mimic tissue transglutaminase and to be immunogenic in CD patients. Recently, both mTG and gliadin were found to be transported to the endoplasmic reticulum of enterocytes, suggesting cross-presentation and potential interaction with immune cells in CD. Although pathogenetic activity of mTG has not been found to date, these data naturally raise concerns among clinicians and patients about the use of mTG as a food additive. On the contrary, different studies have shown that treatment with mTG was effective in reducing the inflammatory immune response of gluten in CD. In this article, we take advantage of recent advances in gut physiology and CD pathogenesis to revise the literature data on mTG. An updated and unbiased overview of the role of mTG in this pathology allowed us to definitively highlight the beneficial use of this food additive by CD patients.

Assessment of the biotechnological activity of wheat hydrolysates prepared with the Biarum bovei extract

In this study, Biarum bovei extract was used to produce bioactive peptides from wheat gluten protein and the biological and functional properties of the hydrolysates were determinated. The results showed that Biarum bovei extract has its highest protease activity (7.3 U/mg protein) at 45 °C and pH 5. Based on electrophoresis analysis, the molecular weight of hydrolysate was < 10 kDa. F1 fraction had the highest antioxidant activity in DPPH (65.85 ± 2.64 µmol TE/g)) and ABTS radical scavenging assays (295.81 µmol TE/g). F2 fraction with 86.3 ± 0.48 had the ability to inhibit the ACE enzyme. The F3 and F1 fractions had statistically the highest inhibition rate (49.37 ± 0.12%. and 79.19 ± 1.13%) in alpha-glucosidase and alpha amylase, respectively. The F1, F2 fractions hydrolysate had an inhibitory effect on Escherichia coli, Staphylococcus aureus, Listeria monocytogenes and Bacillus cereus. Functional properties of hydrolysates with increasing molecular weight, increased significantly. The presence of high levels (p ≤ 0.05) of amino acids with hydroxyl groups, hydrophobic and positive charged in fractions had critical role on biological and technological activity. These findings confirmed the efficiency of gluten hydrolysates with low molecular weight (F1 < 3 kDa) on biofunctionality such as scavenging radical activity, ACE inhibitory, antidiabetic and antibacterial activity could be beneficial from health and technological perspectives.

Preliminary assessment of a novel fermented wheat protein concentrate from a bio-distillation source as a dietary ingredient contribution for tilapia (Oreochromis niloticus)

A novel technologically advanced fermented wheat gluten and yeast sourced protein (FWPC) co-product utilising Saccharomyces cerevivisiae yeast was evaluated for juvenile Nile tilapia Oreochromis niloticus. The protein component of a semi-purified basal diet (control treatment) was incrementally replaced by Fermented Wheat Protein Concentrate (FWPC) at 10%, 20%, and 30% of total dietary protein to create a slope-assay response to the test ingredient compared to an ‘ideal protein’ essential amino acid EAA balanced source. After an 8-week feeding trial, tilapia fed 10% and 20% FWPC displayed similar performance to those fed the control FM based diet, while fish fed 30% FWPC gave the lowest growth performance (P ≤ 0.05) compared to the other treatments. Proximate composition analysis showed that body protein, lipid, ash, NFE and gross energy were unaffected by dietary treatment (P ≥ 0.05). Both plasma alanine aminotranferase (ALAT) and aspartate aminotranferase (ASAT) were measured as indicators of hepatic function in Nile tilapia. No effects were seen in ALAT and ASAT activities. Tilapia fed 30% FWPC showed reduced HSI (P ≤ 0.05) compared to the other treatments. Additionally, histological comparisons of liver and intestinal tissues gave no indication of impairment to health, but FWPC inclusion elevated the number of goblet cells present in the posterior intestine (P ≤ 0.05). Ultrastructure of microvilli height and density also increased significantly showing functional aspects of FWPC. This study reveals the potential benefits of utilising a potable alcohol derived FWPC on the growth and feed utilisation performance of Nile tilapia, with no apparent adverse impacts on general health and physiological status as determined by gut and liver function and related plasma metabolic status. The results are discussed in the context of a promising protein ingredients source for tropical fish aquaculture.

Targeting Induced Local Lesions in the Wheat DEMETER and DRE2 Genes, Responsible for Transcriptional Derepression of Wheat Gluten Proteins in the Developing Endosperm.

Wheat is a major source of energy and nutrition worldwide, but it is also a primary cause of frequent diet-induced health issues, specifically celiac disease, for which the only effective therapy so far is strict dietary abstinence from gluten-containing grains. Wheat gluten proteins are grouped into two major categories: high-molecular-weight glutenin subunits (HMWgs), vital for mixing and baking properties, and gliadins plus low-molecular-weight glutenin subunits (LMWgs) that contain the overwhelming majority of celiac-causing epitopes. We put forth a hypothesis that eliminating gliadins and LMWgs while retaining HMWgs might allow the development of reduced-immunogenicity wheat genotypes relevant to most gluten-sensitive individuals. This hypothesis stems from the knowledge that the molecular structures and regulatory mechanisms of the genes encoding the two groups of gluten proteins are quite different, and blocking one group's transcription, without affecting the other's, is possible. The genes for gliadins and LMWgs have to be de-methylated by 5-methylcytosine DNA glycosylase/lyase (DEMETER) and an iron-sulfur (Fe-S) cluster biogenesis enzyme (DRE2) early during endosperm development to permit their transcription. In this study, a TILLING (Targeting Induced Local Lesions IN Genomes) approach was undertaken to identify mutations in the homoeologous DEMETER (DME) and DRE2 genes in common and durum wheat. Lines with mutations in these genes were obtained that displayed reduced content of immunogenic gluten proteins while retaining essential baking properties. Although our data at first glance suggest new possibilities for treating celiac disease and are therefore of medical and agronomical interest, it also shows that inducing mutations in the DME and DRE2 genes analyzed here affected pollen viability and germination. Hence there is a need to develop other approaches in the future to overcome this undesired effect.

Optimization of the Technology for Preparing Salty Wheat Gluten Protein Hydrolysate by Compound Enzyme Method

Optimization of the Technology for Preparing Salty Wheat Gluten Protein Hydrolysate by Compound Enzyme Method

Modulation of Mucin Secretion in the Gut of Young Pigs by Dietary Threonine and Non-Essential Amino Acid Levels.

Simple SummaryThe mucus layer is an important part of the system protecting the gut against injuries and bacterial infections. The main components of mucus responsible for its properties are mucins. They are large glycoproteins with a protein core rich in threonine (Thr) and many sugar side chains that differ in structure and affect mucin functions. Diet composition affects the amount of secreted mucins and their quality. Therefore, the aim of the study was to determine the effect of Thr and wheat gluten (WG) protein, added as a source of non-essential amino acids, on the content of tissue and luminal mucins in different parts of the intestine of young pigs. Results showed that tissue and luminal mucin content was only affected by WG levels in the duodenum and middle jejunum, and in the proximal colon, respectively. The effect of WG on luminal mucin content in the proximal colon depended on the analytical method applied.The aim of the study was to determine the effect of threonine (Thr) and non-essential amino acid (NEAA) levels on mucin secretion and sugar composition of digesta and crude mucin preparations analyzed in different segments of the gut in young pigs. A two-factorial experiment was conducted on 72 pigs using the following factors: Thr level (5.1, 5.7, 6.3 and 6.9 g standardized ileal digestible(SID) Thr/kg) and wheat gluten (WG) level used as a source of NEAA (20.4, 40.4 and 60.4 g WG protein in WG20, WG40 and WG60 diets, respectively). Mucin content was affected only by WG level. Tissue mucin content in the duodenum was higher in WG60 pigs than in WG20 and WG40 pigs, whereas in the middle jejunum was higher in WG40 and WG60 pigs than in WG20 pigs. In contrast, luminal crude mucin content in the proximal colon was lower in WG60 pigs compared to WG40 pigs. The lowest and highest Thr levels reduced arabinose and xylose contents and increased glucose content in ileal digesta. The highest WG level reduced arabinose and xylose contents and increased glucose content in ileal digesta. The lowest WG level increased mannose content in ileal digesta. WG60 level decreased the content of arabinose and galactose compared to lower WG levels in colonic digesta. Arabinose content was higher, while glucose and galactose contents were lower in crude mucin preparations isolated from colonic digesta in pigs fed diets containing the highest Thr level. The content of tissue mucin was higher in the ileum and proximal colon and lower in the duodenum than in the middle jejunum, whereas luminal mucin content was lower in the proximal colon than in the ileum. Ileal digesta contained less arabinose and glucose and more galactose as compared to colonic digesta. In conclusion, no effect of dietary Thr levels on mucin secretion in the gut of young pigs was found. Wheat gluten added to the diet with adequate Thr content positively affected mucin secretion only in the duodenum and middle jejunum.

Innovative Green Way to Design Biobased Electrospun Fibers from Wheat Gluten and These Fibers' Potential as Absorbents of Biofluids.

In this study, a new method was developed to successfully design sustainable microfibers from wheat gluten proteins using a nonreducing solvent and electrospinning. We explored the morphology by X-ray tomography, scanning electron microscopy (SEM), and confocal laser scanning microscopy (CLSM), protein chemistry and cross-linking by size exclusion-high-performance liquid chromatography (SE-HPLC), and secondary structure by Fourier transform infrared spectroscopy (FT-IR) of fibers containing 15 and 20% of gluten. The impact of heat (130 °C) post-treatment on the polymerization properties of fibers and their absorption performance in different biofluids were also evaluated. The fibers with 20% gluten showed a uniform architecture supported by a relatively stronger fibrous network as compared to irregular and brittle fibers from 15% gluten. Heat treatment of fibers increased the protein cross-linking in all electrospun fibers as compared to the non-heat-treated fibers, as evidenced by SE-HPLC. An increase in the amount of α-helices and random coils was observed in the proteins of all of the heat-treated fibers compared to the nontreated fibers by FT-IR. This suggested that the heat treatment contributed positively to the gluten protein's chemical rearrangements, e.g., aggregation, new hydrogen and isopeptide bonding, and conversion of some of the sulfhydryl groups into disulfide cross-links, contributing positively to the functional performance. The heat-treated electrospun fibers with 20% gluten showed a very attractive blood absorption capacity (323%) and reasonable stability in phosphate-buffered saline (PBS) buffer compared to 15% gluten fibers and non-heat-treated fibers. Cotton-like fiber architecture, high blood absorption capacity, and reasonable stability in PBS buffer are properties desired for absorbents of biofluids and should be further explored in healthcare and medical applications.

Development of Easy-Handling, Formaldehyde-Free, High-Bonding Performance Bio-Sourced Wood Adhesives by Co-Reaction of Furfuryl Alcohol and Wheat Gluten Protein

Development of Easy-Handling, Formaldehyde-Free, High-Bonding Performance Bio-Sourced Wood Adhesives by Co-Reaction of Furfuryl Alcohol and Wheat Gluten Protein

Controlled and Prolonged Release Systems of Urea from Micro‐ and Nanomaterials as an Alternative for Developing a Sustainable Agriculture: A Review

The world population requires the increase of food products from agricultural fields and also the improvement of agricultural practices to avoid the environmental pollution. Urea is the most used fertilizer worldwide; however, it is lost to the environment by processes such as leaching, volatilization, and denitrification. As an alternative to avoid these losses, controlled‐release fertilizer (CRF) and prolonged release fertilizer (PRF) have been proposed. With this type of system, the plants could take the necessary amount of nutrients for their growth at the same time decreasing the environmental pollution. These systems could be fabricated from both synthetic and natural sources, such as wheat gluten proteins, polysaccharides, and composites (polymeric matrix, wheat‐gluten‐urea mix, among others). This review gives a sustainable agriculture approach in the application of CRF and PRF using inorganic and organic raw materials, focusing on the use of wheat gluten proteins and urea for the development of these systems.

Wheat gluten proteins phosphorylated with sodium tripolyphosphate: Changes in structure to improve functional properties for expanding applications

Poor solubility of wheat gluten proteins (WG) has negative impact on functional attributes such as gelation and emulsification, which limits it use in the food industry. In this study, WG underwent different degrees of phosphorylation using sodium tripolyphosphate (STP). Phosphoric acid groups were successfully incorporated in the WG via covalent bonding (C–N–P and C–O–P) involving hydroxyl and primary amino groups from WG. The introduction of phosphoric acid groups increased the negative charge of phosphorylation-WG, which caused the enhancement of electrostatic repulsion between proteins and reduced the droplet size in emulsions, thereby allowing proteins to be more efficiently dispersed in the solution system. The change of structure induced with phosphorylation improved hydration of protein, making the WG with higher solubility, thereby resulting in the improvement of its emulsification, foaming, thermal stability, and rheological properties. Therefore, WG can be modified by phosphorylation which caused an overall improvement of functional properties, thus facilitating the expansion of WG applications.

Effects of different frozen storage conditions on the functional properties of wheat gluten protein in nonfermented dough

The functional properties of wheat gluten protein isolated from nonfermented dough stored at -6 °C, -12 °C, -18 °C, -24 °C and -30 °C for 10 d, 20 d and 30 d were investigated. The solubility and water holding capacity of gluten protein decreased with decreasing frozen storage temperatures and increasing frozen storage time. The foamability of gluten protein was not affected by different frozen storage temperatures. However, the foamability of gluten protein decreased with extension of the frozen storage time. The storage modulus (G') and loss modulus (G") of gluten decreased with decreasing frozen storage temperatures. Meanwhile, the storage modulus (G') and loss modulus (G") of gluten increased with extension of the frozen storage time. When the frozen storage temperature of gluten was -12°C, the frozen water content was lower than that in gluten with other frozen storage temperatures. The water migration of gluten protein under different frozen storage temperatures and times was measured by low-field NMR. The microstructure of gluten protein was also observed under a scanning electron microscope. It was found that more serious damage to the gluten structure occurred with lower freezing temperatures and longer freezing times.