Properties Of Gluten Research Articles

Aqueous ozone effects on wheat gluten: Yield, structure, and rheology.

This study investigates the impact of aqueous ozone (AO) on the yield, molecular structure, and rheological properties of wheat gluten separated using the batter procedure. Employing strong gluten flour (SGF) and weak gluten flour (WGF), we demonstrate that AO pretreatment significantly enhances the yield and purity of separated starch and gluten. Surface hydrophobicity, free sulfhydryl groups, Fourier transform infrared spectroscopy (FTIR), Raman, and size exclusion-high-performance liquid chromatography (SE-HPLC) analyses were used to evaluate the effects of AO on the molecular structure of gluten. Our analysis reveals that low concentrations of AO induce specific modifications in gluten proteins. AO treatment increases cross-linking in glutenin macropolymer (GMP), reduces surface hydrophobicity, and stabilizes secondary and tertiary structures. These changes include an increase in β-sheet content by approximately 9% and a corresponding decrease in β-turn structures, leading to enhanced viscoelastic properties of the gluten. The research highlights AO's potential as a sustainable and efficient agent in wheat flour processing, offering advancements in both product quality and eco-friendly processing techniques. Future research should optimize AO treatment parameters and explore its effects on different cereal types further to enhance its applicability and benefits in food processing. PRACTICAL APPLICATION: Our work substantially advances the existing knowledge on wheat flour processing by demonstrating the multifaceted benefits of AO pretreatment. We unveil significant improvements in the yield and purity of starch and gluten when compared to conventional separation methods. Moreover, our in-depth analysis of molecular changes induced by AO, including increased cross-linking, alterations in surface hydrophobicity, and modifications in glutenin macropolymer content, provides new insights into how AO affects the viscoelastic properties of gluten. This contribution is pivotal for the development of more efficient, sustainable, and eco-friendly wheat flour processing technologies.

Image-assisted quantification of high and low molecular weight glutenin fractions in wheat by SDS-PAGE

Gluten quality in bread wheat is mainly determined by gluten strength and protein content. Traditionally gluten quality has been predicted based only on allelic variation for HMW-GS characterized by SDS-PAGE- The ratio of high to low molecular weight glutenin subunits has received less attention despite its influence on gluten properties is acknowledge. That is mainly because accurate quantification of glutenin fractions is made by RP-HPLC, a more complex, expensive and time-consuming technology. In the present study, a methodology to estimate HMW/LMW glutenin subunit ratio by SDS-PAGE results was assessed. We used a segregating population derived from a cross between two Spanish bread wheat landraces (Richela Blanca and Jeja Pardilla) showing striking differences according to SDSS tests. Quantification of prolamins by RP-HPLC confirmed a wide range of variation in the HMW/LMW glutenin subunit ratio within the population. Then, we selected 22 lines that represented the available variation. Subsequently, we obtained high-quality SDS-PAGE images following a standard protocol to characterize glutenin allelic variants. Estimation of HMW/LMW-GS ratio was obtained by analyzing the intensity of HMW-GS and LMW-GS gel bands. Correlation between RP-HPLC and SDS-PAGE values was greater than 0.85 proving the suitability of the much simpler and cheaper electrophoretic-based alternative.

Influence of salts on the protein composition and functionality of gluten

Different salts were added to gluten to investigate the effects of different cations on a fully developed gluten network. The chloride salts KCl, NaCl, MgCl2, CaCl2 were mixed with pre-isolated wet gluten in a low and high dose, and the gluten was dried at 40 °C and 80 °C to yield vital gluten. The impact of the individual cations on the gluten protein composition and functionality was determined by analysis of chemical and rheological properties of vital and wet gluten. All cations influenced the gluten protein composition and the rheological behaviour. While the observed changes could not be attributed to the order of the Hofmeister series, monovalent, kosmotropic cations K+ and Na+ and divalent, chaotropic cations Mg2+ and Ca2+ showed similar behaviour in terms of protein composition and functional properties. Salts therefore have an influence on the gluten protein composition of a fully developed gluten network and gluten protein composition and functionality can be altered by an after-treatment process in a targeted way.

Effect of enzymatic processing on the physicochemical properties of wheat gluten protein enzymatic products

AbstractBackground and ObjectivesWheat gluten is a high‐quality, low‐priced, and nutritious plant protein. Applications of wheat gluten protein could be expanded by improving its solubility through enzymatic modifications. Herein, we investigated the effect of proteolytic processing on the physicochemical properties of wheat gluten protein.FindingsThe degree of hydrolysis, trichloroacetic acid‐soluble nitrogen (TCA‐SN), and peptidyl nitrogen content of the enzymatic digestion products increased, and the TCA‐SN content exceeded 60% in all cases. The ζ‐potentials of all products after enzymatic digestion were significantly decreased and were negative. Three enzymatic solutions increased the stability of the solution system and the surface hydrophobicity of the enzymatic products to different degrees. The products after enzymatic digestion by alkaline protease had better antioxidant capacity.ConclusionsThis study provides theoretical support for expanding the applications for wheat protein to achieve the added value of wheat products and enhance the utilization rate of these readily available raw materials.Significance and NoveltyThis study investigates the dual enzyme stepwise enzymatic hydrolysis of wheat gluten protein by alkaline protease and neutral protease, which increases the water‐soluble protein content of wheat gluten protein. The resulting hydrolysate has a high peptide nitrogen content.

Genome wide association mapping of end-use gluten properties in bread wheat landraces (Triticum aestivum L.)

Numerous studies have aimed to dissect the genetic basis of wheat end-use quality, yet the consideration of gluten aggregation properties in this context has been limited despite its important role in determining the processing quality. This study has addressed the evaluation of the end-use quality of a collection of 189 Spanish bread wheat (Triticum aestivum L.) landraces. For phenotyping, we utilized the GlutoPeak methodology to assess gluten aggregation traits, the SDS-sedimentation test to measure gluten strength and NIR for grain protein content. In addition to previous genotyping data with numerous DArT-seq markers distributed across the entire wheat genome, we developed ten KASP-based molecular markers designed for GLU-1 loci, which encode high molecular weight glutenins (HMW-GS). The reliability of these markers was thoroughly assessed. Our genome-wide association analysis (GWAS) focused on gluten properties and protein content, revealed 89 marker-trait-associated loci (MTAs). These loci were further grouped into 50 MTA-QTLs across various chromosomes based on linkage disequilibrium. While some MTA-QTLs overlapped with regions identified in other studies, others represented novel genomic regions. Inside these regions, we identified several candidate genes with gluten quality-related annotated functions or grain-specific expression patterns, which represent potential targets for marker development and future wheat end-use quality improvement.

Effects of purple cabbage anthocyanin extract on the gluten characteristics and the gluten network evolution of high-gluten dough.

Anthocyanins are polyphenolic pigments that have hypoglycemic, antioxidation, anti-aging, and other effects. Research has shown that polyphenols can optimize the processing of dough and improve the texture and nutritional characteristics of dough products. The formation of gluten networks is decisive for the quality of flour products. The effects of purple cabbage anthocyanin (PCA) extract on the structure, microscopic morphology, and network formation of gluten protein were studied, and the types of cross-linking between PCA and gluten protein are discussed. The results show that PCA extract increased the free sulfhydryl (SH) group content and the free amino group of gluten proteins, stimulated an increase in the β-sheet ratio and the decrease of α-helix ratio, and increased the gluten index significantly (P < 0.05). The PCA extract also induced gluten protein aggregation, increased the height of protein molecular chains, and stimulated the formation of gluten networks. When PCA extract concentrations were 4 g kg-1 and 8 g kg-1, the gluten network was more homogeneous, continuous, and dense. Appropriate anthocyanins have a positive effect on the properties of gluten and promote the formation of gluten networks. Excessive anthocyanins destroy gluten protein interaction and harm gluten cross-linking. This study may provide a useful source of data for the production of functional flour products rich in anthocyanins. © 2024 Society of Chemical Industry.

Composition of high-molecular-weight glutenin subunits and gluten quality in wheat lines with alien genetic material

Background. High-molecular-weight glutenin subunits (HMW-GSs) make the greatest contribution to the formation of baking properties in bread wheat (Triticum aestivum L.). Glutenin polymorphism of bread wheat relatives is significantly richer than in cultivated varieties. The objective of this work was to identify the HMW-GS composition and assess the gluten quality of bread wheat lines with introgressions of alien genetic material.Materials and methods. We studied the parental varieties of spring bread wheat, accessions of the tetraploid and hexaploid Triticum L. species, and 19 introgressive lines produced with their participation. Glutenins were separated using sodium dodecyl sulfate polyacrylamide gel electrophoresis and HMW-GSs were identified using the Payne nomenclature system. Gluten quality was determined in accordance with GOST 13586.1-68 (the 2017–2019 and 2021–2022 growing seasons). Data processing was performed using the Statistica 10.0 and MS Excel software packages.Results and conclusion. HMW-GSs uncharacteristic of T. aestivum cultivars were identified in the studied accessions of T. dicoccoides (Körn. ex Aschers. et Graebn.) Schweinf., T. spelta L., and T. kiharae Dorof. et Migusch. These HMW-GSs are of interest for enriching the wheat gene pool. HMW-GSs of related species were found in 10 out of 19 introgressive lines. A five-year observation period revealed that wheat relatives on average significantly exceeded common wheat cultivars in gluten quality, and introgressive lines did not differ significantly from the parental genotypes. Lines with high rheological properties of gluten had, as a rule, HMW-GSs of related species in their composition.

A comparative study of molecular structure, rheology, and thermal characteristics of deacetylated konjac glucomannan-treated gluten during frozen storage

Konjac glucomannan is extensively employed to enhance the quality of wheat-based products. Despite this, the utilization of natural KGM in the food industry is restricted due to its inadequate mechanical attributes, heightened susceptibility to humidity, and unappealing taste profile. In this study, the influence of deacetylated konjac glucomannan (DKGM) on the structure, rheology, and thermal characteristics of gluten during frozen storage was explored. Furthermore, the mechanism outlining the action between gluten and DKGM was analyzed. The secondary structure results showed that DKGM promoted the formation of α-helices and β-sheets in gluten. Scanning electron microscopy analysis confirmed that DKGM made the gluten network more stable. Moreover, DKGM provided a significant improvement in the rheological and thermal properties of frozen gluten. This is attributes to the fact that DKGM alters the hydrophobic residues in frozen gluten. Overall, this work indicates that the molecular structure and thermal properties of gluten are optimally substantial improvements at a substitution content of 1.5% D3 (deacetylation degree of 95%) in the dough. These findings provide a reference value for the application of DKGM in frozen wheat-based foods.

Purified protein glutaminase from Chryseobacterium proteolyticum enhances the properties of wheat gluten

Protein glutaminase (PG), originating from Chryseobacterium proteolyticum, can catalyze the deamidation of glutamine residues in plant proteins into glutamic acid, thus enhancing its functional properties. However, the low yield of PG limits its industrial production. In this study, the yield of PG in C. proteolyticum TM1040 increased by 121 %, up to 7.30 U/mL in a 15 L fermenter after medium optimization. Subsequently, purified PG was obtained by cation exchange chromatography (CEX) coupled with hydrophobic interaction chromatography (HIC). The degree of deamidation (DD) of wheat gluten after purified PG deamidation was 87.11 %, which is superior to chemical deamidation in safety and DD. The emulsifying and foaming properties of deamidated wheat gluten were 2.67 and 18.86 times higher, and the water- and oil-holding properties were 4.23 and 18.77 times higher, respectively. The deamidated wheat gluten with enhanced functional properties was used to improve the flavor and texture in baking cakes.

Changes in the molecular and structural of wheat gluten in the presence of zein during heating: Comparative studies on gluten, glutenin and gliadin

This study comparatively investigated the heat-triggered molecular and structural changes of wheat gluten in the presence of zein to clarify the gluten and zein interaction mechanism from the perspective of gluten, glutenin, and gliadin polymerization behavior during heating. Scanning electron microscopy (SEM) images showed that zein induced more uniform dispersion of the gluten network during heating. Size exclusion-high performance liquid chromatography (SE-HPLC) results demonstrated that zein addition increased the SDS-soluble protein content in the gluten, glutenin, and gliadin during heating. After heating at 95 °C, zein increased the free sulfhydryl content in gluten and glutenin by 23.15% and 38.97%, respectively. Zein primarily enhanced the non-covalent interaction with gliadin more than with gluten and glutenin. The addition of zein led to a significant decrease in β-sheets content in gluten, glutenin, and gliadin during heating. Zein improved the thermal stability of gluten and gliadin after heating, resulting in higher degradation temperatures and lower weight loss. The improvement in rheological properties of gluten, glutenin, and gliadin during the 95 °C heating phase could be mainly attributed to the prevention of excessive protein aggregation and the promotion of non-covalent interactions by zein.

Effect of phosphorylation of long‐chain inulin on the rheological properties of wheat flour doughs with different gluten

SummaryIn this study, double long‐chain inulin phosphate (PDFXL) was prepared by chemically modifying long‐chain inulin (FXL) through phosphorylation. The effects of FXL and PDFXL on the rheological properties of low gluten (L‐G), medium gluten (M‐G), and high gluten (H‐G) dough were investigated using Fourier Transform Infrared (FT‐IR) and rheometer. The FT‐IR and solubility results indicated that PDFXL exhibited stronger hydrophilicity and promoted protein cross‐linking. Rheological tests revealed that the apparent viscosity of L‐G, M‐G, and H‐G dough decreased with increasing shear rate. Notably, M‐G PDFXL doughs exhibited higher shear thinning behaviour. Additionally, in the frequency and temperature sweep test, M‐G and H‐G PDFXL doughs showed higher elasticity and viscous modulus. This study reveals the modification effect of phosphorylation on FXL, providing a scientific foundation for the comprehensive application of PDFXL in flour products.

Microwave-treated rice flour halves the need of hydroxypropyl methylcellulose in the formulation of gluten-free bread

Hydrocolloids such as hydroxypropyl methylcellulose (HPMC) are commonly used in gluten-free (GF) products to mimic the viscoelastic properties of gluten. However, GF products must meet current consumer expectations by not only being tasty and nutritious, but also adhering to ‘clean label’ principles, which involve minimizing ingredients and additives and favoring natural over chemical components. Modifying GF flours via hydrothermal treatments offers an alternative approach to reduce the use of additives in GF products. This work applied response surface methodology to study the potential reduction in HPMC dose in the formulation of GF-breads by the addition of microwave-treated rice flour (MWF) (treatment conditions: 8 min, 9 W/g, 30% moisture), without impairing their appearance, volume, and texture. The optimization study also included Water level and HPMC dose, and evaluated the dough's rheological properties at constant hydration. GF breads were made by varying the amount of native flour substituted with MWF, water level, and HPMC dose. Replacing 50% or 80% of native rice flour by MWF allowed to reduce the usual HPMC dose by more than half. This resulted in higher loaf volume and a softer crumb than their counterparts made with untreated flour and baked with the usual dose of additive (2%). Doses of HPMC as low as 0.7% with 80% MWF still resulted in breads with good texture and acceptable volume. Therefore, the structuring effect of MWF and its good performance in GF baking have been concluded, allowing to reduce the dose of additives required in formulating GF bread.

Properties of wheat gluten based wood adhesives enhanced by transglutaminase and epichlorohydrin

Bio-based eco-friendly products are well-received globally due to increasingly scarce petroleum resources and growing public concern about human health risks and environmental concerns. In this study, wheat gluten (WG) as the raw material modified with transglutaminase (TGase) and epichlorohydrin (ECH) was used to develop an eco-friendly bio-based adhesive. Effects of TGase and ECH on the properties of the adhesive were emphatically discussed. The dry and wet shear strengths of the combined modified adhesive achieved at 3.21 MPa and 0.81 MPa, which was higher than the Chinese National Standard Ⅱ plywood requirements (0.7 MPa). Meanwhile, the solid content and the protein surface hydrophobicity H0 were increased to 28.27 % and 636.54, respectively. These improvements were mainly because, during the modification, the structure of WG became more stretched after ethanol treatment. Then the TGase promoted the cross-linking of the protein molecules and enhanced the cohesion strength of the adhesive system. Finally the ECH further cross-linked and aggregated with exposed active groups to varying degrees, and formed a compact three-dimensional cross-linked network structure, which allowed the WG-based adhesive to form a smoother and more uniform microscopic surface and better water resistance. The obtained adhesives might be utilized to substitute petroleum-derived adhesives in the plywood sector, providing ideas and references for future eco-friendly adhesive research and increasing the high value usage of wheat starch processing by-products.

WHEAT FLOUR QUALITY CORRECTION BY USING ENZYME PREPARATIONS

Over the past decade, the flour milling industry has been undergoing active development, with the reconstruction of existing enterprises and increased construction of new flour mills under conditions of declining quality of incoming raw materials, high competition and low profitability of bakery enterprises and flour mills. Therefore, such enterprises should be able to produce not only standard flour but also flour with specified quality indicators. One example is flour with enhanced baking properties intended for special product groups such as loaves, baguettes, buns, etc. Standard Ukrainian flour, produced due to its low protein and gluten content, cannot always be used for these products. The aim of the study was to investigate the effect of a protease-acting enzyme preparation on the gluten network of flour and to develop a complex-acting technological additive. To study the quality of flour, both conventional and innovative evaluation methods were used with the help of the Mixolab device, and trial laboratory baking of samples was carried out. To improve the protein-proteinase complex, the enzyme preparation Neutrase 15 BG was used in three dosages: minimum (0.02 g/kg), medium (0.06 g/kg) and maximum (0.1 g/kg). For complex action, a mixture of enzyme preparations Neutrase 15 BG and Fungamyl 2500 SG in the following dosages: 0.02 g/kg + 0.002 g/kg; 0.02 g/kg + 0.005 g/kg; 0.02 g/kg + 0.01 g/kg. The paper analyses the quality of flour produced by Ukrainian producers, determines the effect of a proteolytic enzyme on the quality characteristics of gluten, evaluates the baking properties of graded flour with a proteolytic enzyme, and develops a technological additive to adjust the protein-proteinase complex of flour. The analysis of previous studies has shown that high-grade flour from the Southern region is characterised by low quality, namely a low gluten content of 24.0-25.2% with excessively resistant gluten properties of 47-60 units, and low amylolytic activity – the falling number is above 460-480 s. It has been established that at the minimum and average dosage of Neutrase 15 BG, the specific volume of bread increased by 0.5% and at the maximum – by 0.2%, with a clear deterioration in organoleptic characteristics. Therefore, it makes sense to use this enzyme in low dosages to prevent stickiness of the dough. According to the results of the influence of the technological additive on bread quality indicators, it has been found that in the sample with the following dosage of Neutrase 15 BG and Fungamyl 2500 SG – 0.02 g/kg + 0.01 g/kg, respectively, the volume and porosity of bread increased by 1.3 times and 1.1 times, respectively.

Insights into the mechanisms underlying ethanol-induced changes in the dough mechanical properties and quality characteristics of fresh noodles

This study investigated the effects of ethanol (0 %∼6%) on the dough mechanical properties and quality characteristics of fresh noodles and elucidated the relationship between the above changes and physicochemical, structural, and molecular properties of gluten. Ethanol reduced the water absorption (from 59.00 % to 52.33 %), stability time (from 8.17 min to 3.33 min) and viscoelasticity of dough, and increased the development time, weakening degree and compliance. Ethanol also decreased the fracture stress of dough sheet, and increased fracture elongation and adhesiveness (from 46.15 g·s to 75.88 g·s). Ethanol decreased the noodles’ hardness (from 5347.41 g to 4442.34 g), break force, tensile distance, and water absorption, while cooking loss was increased. SEM and CLSM showed that ethanol destroyed the compactness of internal structure and inhibited the formation of gluten network in noodles. According to the results of SE-HPLC and RP-HPLC, ethanol dissolved part of the gliadin and inhibited the polymerization of protein.

Overview of test methods used to classify wheat flour and bread samples – REVIEW

In Hungary, common wheat (Triticum aestivum ssp. vulgare) is of good quality and world famous. In addition, it plays an important role in the human diet. The classification of flours ground from wheat is quite decisive and there are several methods for its examination. The most important flour testing requirements include moisture content, protein content gluten properties and the most important bakery value number. The measured characteristics give us the opportunity to conclude about the properties of the dough, and then bakery products. Several dynamic and static methods have been developed to study the physical properties of dough. The evaluation of products can be carried out in several respects with the help of a baking test. The multitude of methods currently used to qualify flour, dough and finished products also proves that the overview of the methods is quite topical.

Wheat gluten deamidation: structure, allergenicity and its application in hypoallergenic noodles.

Wheat gluten (WG) containing gliadin and glutenin are considered the main allergens in wheat allergy as a result of their glutamine-rich peptides. Deamidation is a viable and efficient approach for protein modifications converting glutamine into glutamic acid, which may have the potential for allergenicity reduction of WG. Deamidation by citric acid was performed to investigate the effects on structure, allergenicity and noodle textural properties of wheat gluten (WG). WG was heated at 100 °C in 1 m citric acid to yield deamidated WG with degrees of deamidation (DD) ranging from DWG-25 (25% DD) to DWG-70 (70% DD). Fourier-transform infrared and intrinsic fluorescence spectroscopy results suggested the unfolding of WG structure during deamidation, and sodium dodecyl sulphate-polyacrylamide gel electrophoresis showed molecular weight shifts at the 35-63 kDa region, suggesting that the deamidation mainly occurred on low molecular weight glutenin subunits and γ- gliadin of the WG. An enzyme-linked immunosorbent assay of deamidated WG revealed a decrease in absorbance and immunoblotting indicated that the intensities of protein bands at 35-63 kDa decreased, which suggested that deamidation of WG might have caused a greater loss of epitopes than the generation of new epitopes caused by unfolding of WG, and thereby reduction of the immunodominant immunoglobulin E binding capacity, ultimately leading to the decrease in allergenicity. DWG-25 was used in the preparation of recombinant hypoallergenic noodles, and the hardness, elasticity, chewiness and gumminess were improved significantly by the addition of azodicarbonamide. The present shows the potential for deamidation of the WG products used in novel hypoallergenic food development. © 2023 Society of Chemical Industry.

THE FUNCTIONAL PROPERTIES OF CHEMICALLY AND ENZYMATICALLY MODIFIED WHEAT GLUTEN

This research was carried out to investigate the effect of chemically (using L-Cysteine) and enzymatically (by papain) modification on the functional properties of hard wheat gluten. The modification process is run by both methods individually and synergistically. The results showed an increase in the degree of hydrolysis (DH) of lyophilized wheat gluten upon adding the reducing agent at different concentrations (50, 100, 150, 200, 250 ppm). The values for (DH) were (5.29, 6.18, 6.22, 6.26, and 7.48%) respectively. While for papain (2000 units / g protein) those values were (10.25, 12.71, 13.54, 13.88, 15.62%) respectively when the reducing agent (same concentration above) and papain were used synergistically. The functional properties (water holding capacity, emulsifying ability and stability, foam formation and stability, protein solubility, and oil holding capacity) of the gluten under study were examined. The results showed that the enzymatic modification significantly improved the functional properties of the experimental proteins compared to the reducing agent modification.

Effect of different enzymes on thermal and structural properties of gluten, gliadin, and glutenin in triticale whole-wheat dough

Three enzymes promoted the development of the gluten network in triticale whole-wheat noodles (TWWN). To further understand the mechanism of gluten enhancement, the effects of three enzymes on the structure of gluten and its fractions (gliadin and glutenin) were evaluated. The results showed that glucose oxidase (GOD), xylanase (XYL), and laccase (LAC) decreased the content of sodium dodecyl sulfate (SDS) extractable proteins. The content of glutenin subunits was reduced by 17.25 %, 30.60 %, and 20.09 % with the addition of GOD, XYL, and LAC, respectively. Furthermore, GOD and LAC increased the content of glutenin macropolymer (GMP) by 2.64 % and 7.71 %, respectively, suggesting the promotion of glutenin aggregation. The addition of three enzymes decreased the weight loss and increased the degradation temperature of the gluten and its fractions. GOD and XYL decreased the fluorescence intensity of gluten and its fractions, except for XYL which increased the fluorescence intensity of glutenin by 10.50 %. Intermolecular interactions and surface hydrophobicity were enhanced by XYL in gluten and its fractions. GOD and LAC decreased the free sulfhydryl content and increased the β-sheet content, suggesting that the covalent interaction between gluten fractions was enhanced. Therefore, this research can enrich the theoretical study of enzymatic cross-linking.

Effects of electrostatic field-assisted freezing on the functional properties and aggregation behavior of gluten

Changes in gluten during the freezing process could cause a deterioration in dough quality, which would be solved by electrostatic field treatment. This paper investigated the effects of electrostatic field assisted freezing (EFAF) on the functional properties, structural characteristics and aggregation behavior of gluten. The results showed that EFAF improved the functional properties of gluten with enhanced water holding, emulsifying and foaming properties. When the electrostatic field was applied, the α-helix content and g-g-g conformation of gluten proteins increased with a maximum of 27.50 % and 40.05 %, respectively, which were significantly different from the control (P < 0.05). The degree of depolymerization of gluten macromolecules decreased when the electrostatic field was applied, and was obtained to be the lowest at 600 V with 5.71 %, which was significantly different from that without applied electrostatic field (P < 0.05). After EFAF, AFM analysis showed a more intact glutenin chain structure and smaller particle size of the gliadin. These results indicated that EFAF improved the functional properties of gluten proteins by the mechanism of slowing down the depolymerization of gluten macromolecules, maintaining the chain structure of gluten, stabilizing the intramolecular disulfide bonds of gliadin, and stabilizing the microstructure of gluten.