Content Amino Research Articles

Conformational and processing properties of a high-active ingredient involving soy protein isolates bound with anthocyanins and its application in cake baking

Soybean protein is of plant origin and is commonly appropriate for improving the processing characteristics of foods. This study aimed to explore a novel functional ingredient that contained soybean protein isolate (SPI) and blueberry anthocyanins (BANs). The spatial conformation and secondary structure of SPI-BANs complexes were analyzed using circular dichroism and fluorescence spectroscopy, the processing properties were investigated as well as the retention of antioxidant activity during thermal treatments. Results showed that the contents of free sulfhydryl and free amino groups in complexes increased to 3.50 and 1.19 folds than those of SPI, respectively, while the surface hydrophobicity decreased by 74.23%. Compared with SPI, the BANs-modified SPI had a smaller particle size of 29.12 nm and a lower zeta-potential of -8.73 mV and on the other hand, the complexes possessed higher solubility (83.08%) and foaming and emulsifying properties (115.08% and 54.03 m2/g). After fortification with SPI-BANs, the baking loss rate and adhesiveness of chiffon cake were reduced by 10.82% and improved to 0.24 N.mm, respectively. The high antioxidant activities of SPI-BANs under heat led to the cake’s bioactivities largely enhanced by 1.99 ~ 12.71 folds, being 345.19 µg Trolox/g for the DPPH radical scavenging activity. This study developed the functional food ingredients as antioxidants and a substitute for animal-based proteins in bakery products, which was safe and sustainable by using the dietary components from plant resources.Graphical

Sonochemical amino-functionalization of hexagonal boron nitride nanosheets produced by liquid phase exfoliation

The functionalization of hexagonal boron nitride nanosheets (hBNNSs) is a powerful strategy to improve their properties, such as dispersibility and stability in aqueous media, biocompatibility, and surface affinity. In this work, we report the functionalization of hBNNSs using a two-step strategy. First, hBN powder was exfoliated at ambient temperature by liquid phase exfoliation method into deionized water/isopropanol mixture and the resultant hBNNSs were characterized by transmission electron microscopy, X-ray diffraction and Raman spectroscopy. In the second step, the surface of the hBNNSs was modified with amino groups by means an ultrasonic wave-assisted functionalization process using hydrazine hydrate as functionalization agent. The amino-functionalization of the hBNNSs was confirmed by Infrared (IR) spectroscopy and thermogravimetric analysis (TGA). Our results showed that in an exfoliation optimized process with a sonication time of 4 h, the yield of hBNNSs reach 66 %, and that the hBNNSs can be dispersed in water, isopropanol, and water/isopropanol 75:25 at concentrations of up to 1.5 mg/mL. IR analysis confirmed that the amino groups were successfully grafted on hBNNSs, whereas TGA curves revealed that the content of –NH2 groups in the NH2-hBNNSs vary from 0.9 to 3.2 wt% depending of functionalization agent amount. Due to the polar nature of the amino groups, the NH2-hBNNSs exhibit higher stability and dispersibility in aqueous media compared with the unmodified hBNNSs. Particularly, the NH2-hBNNSs can be dispersed in water/isopropanol 75:25 at concentration from 7 to 15 mg/mL, depending on the content of amino groups.

Elucidating the gas cell stabilization mechanism of buckwheat-wheat steamed bread induced by transglutaminase: A focus on the foaming and air-water interfacial properties of dough liquor

This work investigated the improvement mechanism of transglutaminase (TG) on the buckwheat-wheat steamed bread qualities from the view of protein structural, foaming and air-water interfacial properties of dough liquor (DL). TG reduced the hardness, ameliorated the crumb structure and enhanced the specific volume of buckwheat-wheat steamed bread by up to 9.0%. The DL yield, protein and water recovery were notably increased as the TG concentration increased to 0.2 U/g, then decreased with the higher TG concentrations. The low TG concentrations (<0.2 U/g) increased the protein molecular weight, and decreased the protein hydrophobicity, free amino and sulfhydryl groups content of DL. The high TG concentrations (>0.2 U/g) tended to induce both protein intermolecular and intramolecular cross-linking, which reduced the average particle size from 9.6 to 4.3 μm as the TG concentration increased from 0.2 to 1.0 U/g. TG markedly improved the foaming capacity and foam stability, decreased the surface tension and strengthened the interfacial films by enhancing the viscoelasticity modulus of buckwheat-wheat DL interfacial protein films. The topography of the air-water interfacial layer revealed that the TG-induced protein cross-linking led to a more homogeneous and denser topographical structure. This work will provide fresh insight into the effects of TG-induced protein cross-linking on gas cell stabilization and relate them to the buckwheat-wheat steamed bread quality properties.

Production of protein-epigallocatechin gallate conjugates using free radicals induced by ultrasound and their gelation behavior

In this study, free radicals generated by ultrasound were used to prepare conjugates of food proteins (soybean protein isolates, sodium caseinate and gelatin) with epigallocatechin gallate (EGCG). The changes in free amino and sulfhydryl group contents were used to confirm the occurrence of conjugation. The formation of covalent interactions on surface hydrophobicity, functional groups, structures, thermal stability, and gelation behavior of three proteins were investigated. The results showed that conjugation led to decrease in free amino and sulfhydryl group contents, reduction in the intensity of amide A and fluorescence intensity, and increase in β-fold content. The conjugation also resulted in a decrease in surface hydrophobicity and thermal stability of soybean protein isolates and sodium caseinate, but an increase in the surface hydrophobicity and thermal stability of gelatin. Furthermore, the covalent bonding between proteins and EGCG improved gel strength, water holding capacity, and resulted in a denser and more compact microstructure.

Effect of transglutaminase on the structure, properties and oil absorption of wheat flour

The structure, properties, as well as the oil absorption characteristics of wheat flour (WF) treated with varying concentrations of transglutaminase (TG) (0 U/g ∼ 50 U/g) were characterized. The content of free amino groups in WF modified by TG (TG-WF) decreased and protein aggregated. The isopeptide bonds and disulfide bonds played important roles in protein crosslinking. The thermal stability, the peak viscosity after gelatinization and protein secondary structure stability of TG-WF were improved. In addition, the oil absorption and surface oil content of TG-WF after frying were reduced. TG enhanced the protein-protein interactions in WF, so that protein played barrier roles in the process of high-temperature frying, protecting the starch particles covered by them from the infiltration of oil, thus reducing the oil absorption of TG-WF during frying. Among them, the oil content of TG-WF-30 U/g after frying was the lowest, which decreased by 10.73 % compared with the control group.

Regulation of tea polyphenols in gluten-glucose Maillard reaction: Evaluation and analysis

Maillard reaction plays an important role in the flavour and color of some food. However, the excessive occurrence of Maillard reaction may affect the quality and safety of food. In this study, a simulated Maillard system composed of gluten and glucose was established to evaluate and analyze the regulatory role of tea polyphenols (TP) in it. The addition of tea polyphenols alleviated excessive browning of the Maillard reaction and significantly inhibited the accumulation of fructosamine and late glycosylation end products in the system. Based on the analysis of laser particle sizer and atomic force microscope, the large particle size distribution and aggregation structure of the Maillard reaction products in the tea polyphenol group disappeared. Further experiments showed that with the addition of tea polyphenols, the free radicals content in the system decreased, while the amount of reaction substrates increased. It was also shown that tea polyphenols effectively inhibited the isomerism of glucose to fructose and affected the content of free sulfhydryl and free amino groups in the system. The results indicated that tea polyphenols can regulate the Maillard reaction between gluten and glucose, which gives it the potential for application in the field of bakery and thermally processed foods.

Grafting of Polyethyleneimines on Porous Silica Beads and Their Use for Adsorptive Removal of Cr(VI) from Aqueous Medium

Porous silica-based adsorbents for hexavalent chromium (Cr(VI)) ion removal were prepared by the combined use of functionalization with (3-glycidyloxypropyl)trimethoxysilane and the grafting of branched and linear polyethyleneimine (BPEI and LPEI). LPEI was prepared from polyethyloxazolin by hydrolysis with HCl. The preparation of LPEI was identified by NMR measurements and the grafting of BPEI and LPEI on the silica beads was confirmed by an XPS analysis. The Cr(VI) ion adsorption of the obtained BPEI-grafted silica beads (BPEI–silica beads) was investigated as a function of the pH value, the content of amino groups, the temperature, the Cr(VI) ion concentration, and the molecular mass of the grafted BPEI chains. The Cr(VI) ion adsorption at pH 3.0 increased with an increase in the content of amino groups, and the maximum adsorption capacity of 1.06 mmol/g was obtained when the content of amino groups was at 2.17 mmol/g. This value corresponds to 589 mg/g−1.8KPEI, and the adsorption ratio of about 0.5 is a noteworthy result. The data fit to the pseudo-second-order kinetic model, and the suitability of this fitting was supported by the results that the adsorption capacity and initial rate of adsorption increased with the temperature. In addition, the equilibrium data followed the Langmuir isotherm model. These results clearly demonstrate that the Cr(VI) adsorption occurred chemically, or through the electrostatic interaction of protonated amino groups on the grafted BPEI chains with hydrochromate (HCrO4−) ions. A higher adsorption capacity was obtained for the silica beads grafted with shorter BPEI chains, and the adsorption capacity of BPEI–silica beads is a little higher than that of linear PEI-grafted silica beads, suggesting that the Cr(VI) ion adsorption is affected by the chain isomerism of PEI (linear and branched) as well as the molecular mass of the grafted PEI chains, in addition to the content of amino groups. The experimental and analytical results derived from this study emphasize that the BPEI–silica beads can be used as an adsorbent for the removal of Cr(VI) ions from an aqueous medium.

Chitosan Properties: A Preliminary Review

The content of amino groups in chitosan becomes the main cause of its differences from chitin in the context of structures and properties such as their chelation, flocculation, and biological functions. Furthermore, the random distribution of chitosan makes it easier to generate intra-and inter-molecular hydrogen bonds. Also, the existence of two hydroxyl groups and one primary amine group in chitosan, which can donate a free pair of electrons, make it soluble in diluted aqueous acetic solvents, and allow the formation of the coordination bonds that increase the possibilities for chemical modification. Its modification includes the incorporation of hydrophobic groups. Therefore, this paper reviews the properties of chitosan.

Investigating the Formation of In Vitro Immunogenic Gluten Peptides after Covalent Modification of Their Structure with Green Tea Phenolic Compounds under Alkaline Conditions.

Celiac disease is an autoimmune disorder triggered by immunogenic gluten peptides produced during gastrointestinal digestion. To prevent the production of immunogenic gluten peptides, the stimulation of covalent-type protein-polyphenol interactions may be promising. In this study, gluten interacted with green tea extract (GTE) at pH 9 to promote the covalent-type gluten-polyphenol interactions, and the number of immunogenic gluten peptides, 19-mer, 26-mer, and 33-mer, was monitored after in vitro digestion. Treatment of gluten with GTE provided an increased antioxidant capacity, decreased amino group content, and increased thermal properties. More importantly, there was a remarkable (up to 73%) elimination of immunogenic gluten peptide release after the treatment of gluten with 2% GTE at 50 °C and pH 9 for 2 h. All of these confirmed that gluten was efficiently modified by GTE polyphenols under the stated conditions. These findings are important in developing new strategies for the development of gluten-free or low-gluten food products with reduced immunogenicity.

Amination of naringinase to improve citrus juice debittering using a catalyst immobilized on glyoxyl-agarose

A naringinase complex was chemically aminated prior to its immobilization on glyoxyl-agarose to develop a robust biocatalyst for juice debittering. The effects of amination on the optimal pH and temperature, thermal stability, and debittering performance were analyzed. Concentration of amino groups on catalysts surface increased in 36 %. Amination reduced the β-glucosidase activity of naringinase complex; however, did not affect optimal pH and temperature of the enzyme and it favored immobilization, obtaining α-l-rhamnosidase and β-d-glucosidase activities of 1.7 and 4.2 times the values obtained when the unmodified enzymes were immobilized. Amination favored the stability of the immobilized biocatalyst, retaining 100 % of both activities after 190 h at 30 °C and pH 3, while its non-aminated counterpart retained 80 and 52 % of α-rhamnosidase and β-glucosidase activities, respectively. The immobilized catalyst showed a better performance in grapefruit juice debittering, obtaining a naringin conversion of 7 times the value obtained with the non-aminated catalyst.

Water-polymer interactions and mechanisms of water-driven glass transition decrease in non-isocyanate polyhydroxyurethanes with varying hydration sites

Non-isocyanate polyurethanes (NIPUs) with varying content of secondary amino groups along their chain were studied with respect to water absorption and plasticization. Secondary amino groups promote water uptake. Water sorption isotherms in the water activity range 0–0.97 are discussed in terms of various sorption models. Secondary amino groups act as additional hydration sites, increasing monolayer capacity. The red shift of the IR band assigned to the carbonyl of the urethane and the simultaneous blue shift of the urethane N–H bending band show cleavage of the polymer-polymer hydrogen bonds upon water uptake, due to strong interactions between water molecules and hydroxyurethanes constituting the primary hydration sites. A decrease in glass transition temperature (Tg) is observed with increasing water content. The effect is discussed in terms of plasticization and slaving mechanisms, while a peculiar decrease of Tg at very low hydrations is attributed to a mechanism not following common mixing laws.

Effects of three polyphenols with different numbers of phenolic hydroxyls on the structural and interfacial properties and lipid-protein co-oxidation of oil body emulsions

Oil bodies (OBs) are organelles for storing lipids, and they are composed of lipid cores and monolayer phospholipid protein membranes. During storage, membrane proteins anchored in the lipid core are often damaged by lipid oxidation products, leading to oxidative damage and a decreased quality of emulsified foods. Here, three natural antioxidants (gallic acid (GA), epigallocatechin gallate (EGCG), and tannic acid (TA)) were added to OB emulsions to study the effects of polyphenols on protein interfacial properties during oxidation and the lipid-protein co-oxidation behavior. Compared to GA, EGCG and TA with higher molecular weights and hydroxyl substitution showed better antioxidant activity, metal chelating activity, iron reduction ability, and affinity for OB. The polyphenols significantly reduced the contents of free amino and sulfhydryl groups in OB. Infrared spectroscopy analysis indicate that hydrogen bonding and hydrophobic interactions may exist between the polyphenols and OB. During storage, polyphenols inhibited >23% of the primary and secondary lipid oxidation products in the emulsions, whereas the formation of carbonyl groups and disappearance of sulfhydryl groups were only inhibited by 10.7% and 7.4%, respectively, indicating that polyphenols preferentially inhibited lipid oxidation over protein oxidation. Electrophoresis results showed that moderate oxidation (3 days of storage) disrupted the disulfide bonds of proteins. Note that moderate oxidation enhanced the interfacial properties of OB proteins, whereas excessive oxidation led to protein aggregation. This study offers new perspectives on using polyphenols to regulate the lipid-protein co-oxidation in OB, as well as the different properties of OB proteins after oxidation.

Fabrication of MoS2 restrained magnetic chitosan polysaccharide composite for the photocatalytic degradation of organic dyes

Chitosan (CS) polysaccharide is expected to exhibit greater ionic conductivity, which can be attributed to its increased amino group content when it is blended with different semiconducting materials. Herein, the work used this conducting ability of chitosan and prepared a heterogeneous MoS2-induced magnetic chitosan (MF@CS) composite via the co-precipitation method, which was used to scrutinize the catalytic performance with Methylene Blue (MB) and Malachite Green (MG) dyes by visible light irradiation. The saturation magnetization value of the MF@CS composite is found to be 7.8 emu/g, which is less when compared to that of pristine Fe3O4 (55.7 emu/g) particles. The bandgap of the MF@CS composite is ∼ 2.17eV, which exceeds the bandgap (Eg) of bare MoS2 of 1.80 eV. The maximum color removal of 96.3 % and 93.4 % for MB and MG dyestuffs is recognized in the exposure of the visible spectrum, respectively. At a starting dye dosage of 30 mg/L, 0.1 g/L of MF@CS, a pH level of 8−11, and 70 min of contact with direct light. The photocatalyst provides extremely good durability for a maximum of five phases. Hence, the MF@CS matrix is a viable and appropriate substance for the efficient treatment of effluents containing dye molecules.

Schiff base linkage of citral to zinc-casein hydrolysate chelates for preparing starch-based active films against L. monocytogenes on ready-to-eat foods

Listeria monocytogenes (L. monocytogenes) is a foodborne pathogen often found in ready-to-eat (RTE) foods, posing significant threats to human health. In this study, an active film based on cross-linking via Schiff base and electrostatic interaction to inactivate L. monocytogenes on RTE foods was constructed. Zinc-casein hydrolysate chelates (Zn-HCas) was prepared and blended with cationic starch (CSt) to form the substrates of the film. Then, Citral (CI) with excellent antibacterial properties was added to enhance the biological and packaging properties of the film through covalent cross-linking (Schiff base). Based on the zinc ion-activated metalloproteinases produced by L. monocytogenes, the cross-linked film could be disrupted and the release of CI was accelerated. The variation in color, FTIR, and amino group content proved that Schiff base reaction had taken place. Enhanced mechanical properties, barrier properties, thermal stability and antimicrobial activity against L. monocytogenes (exceed 99.99 %) were obtained from the CI/Zn-HCas/CSt film. The application on RTE cheese results demonstrated that the cross-linked film could be employed in active packaging field with the ability in maintaining the original chroma and texture properties of RTE cheese. In summary, the prepared cross-linked film could be used as an active packaging against L. monocytogenes contamination with great potential.

Subcutaneous Application of a Gelatin/Hyaluronic Acid Hydrogel Induces the Production of Skin Extracellular Matrix.

The development of injectable hydrogels with natural biopolymers such as gelatin (Ge) and hyaluronic acid (Ha) is widely performed due to their biocompatibility and biodegradability. The combination of both polymers crosslinked with N-Ethyl-N'-(3-dimethyl aminopropyl) carbodiimide hydrochloride (EDC) can be used as an innovative dermal filler that stimulates fibroblast activity and increases skin elasticity and tightness. Thus, crosslinked Ge/Ha hydrogels with different concentrations of EDC were administered subcutaneously to test their efficacy in young and old rats. At higher EDC concentrations, the viscosity decreases while the particle size of the hydrogels increases. At all concentrations of EDC, amino and carboxyl groups are present. The histological analysis shows an acute inflammatory response, which disappears seven days after application. At one and three months post-treatment, no remains of the hydrogels are found, and the number of fibroblasts increases in all groups in comparison with the control. In addition, the elastic modulus of the skin increases after three months of treatment. Because EDC-crosslinked Ge/Ha hydrogels are biocompatible and induce increased skin tension, fibroblast proliferation, and de novo extracellular matrix production, we propose their use as a treatment to attenuate wrinkles and expression lines.

Covalent conjugation of Inca peanut albumin and polyphenols with different phenolic hydroxyl numbers through laccase catalysis to improve functional properties.

Enzymatic crosslinking is a method that can be used to modify Inca peanut albumin (IPA) using polyphenols, and provides desirable functionalities; however, the effect of polyphenol structures on conjugate properties is unclear. In this study, we selected four polyphenols with different numbers of phenolic hydroxyl groups [para-hydroxybenzoic acid (HBA), protocatechuic acid (PCA), gallic acid (GA), and epigallocatechin gallate (EGCG)] for covalent modification of IPA by enzymatic crosslinking, and explored the structure-function changes of the IPA-polyphenol conjugates. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) analysis showed that laccase successfully promoted covalent crosslinking of IPA with polyphenols, with the order of degree of conjugation as EGCG > GA > PCA > HBA, the IPA-EGCG conjugate showed the highest polyphenol binding equivalents (98.35 g kg-1 protein), and a significant reduction in the content of free amino, sulfhydryl, and tyrosine group. The oxidation of polyphenols by laccase forms quinone or semiquinone radicals that are covalently crosslinked to the reactive groups of IPA, leading to significant changes in the secondary and tertiary structures of IPA, with spherical structures transforming into dense lamellar structures. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging ability and emulsification stability of IPA-EGCG conjugates improved by almost 6-fold and 2.7-fold, respectively, compared with those of unmodified IPA. These data suggest that the higher the number of polyphenol hydroxyl groups, the higher the degree of IPA-polyphenol conjugation; additionally, enzymatic crosslinking can significantly improve the functional properties of IPA. © 2024 Society of Chemical Industry.

Insight into the allergenicity and structure changes of parvalbumin from Trachinotus ovatus induced by dense-phase carbon dioxide

Parvalbumin (PV) is a major allergen in fish, and traditional treatments cannot reduce its sensitization. The effects of dense-phase carbon dioxide (DPCD) treatment on the sensitization and spatial structure of PV in Trachinotus ovatus were evaluated in this study. Western blotting and indirect ELISA were used to determine the allergenicity changes and spatial conformations of PV treated by DPCD. Tris-tricine-SDS-PAGE, circular dichroism, surface hydrophobicity, endogenous fluorescence, UV spectrophotometry, free amino group, total sulfhydryl group and SEM analyses were applied to characterize PV structure. The results showed that DPCD treatment (15 MPa, 30 min, 50 °C) could reduce PV-induced allergic reactions by 39–41 %, which destroyed the normal conformational epitopes and reduced the risk of PV-induced allergy. The secondary structure changed from ordered to disordered with a decreased content of α-helical groups, while the internal hydrophobic groups were exposed. The total sulfhydryl group content decreased significantly (P < 0.05). The surface hydrophobicity and ultraviolet absorption spectrum were enhanced, and the endogenous fluorescence peak shifted to a long wavelength. Meanwhile, the content of free amino groups increased significantly (P < 0.05). This study could provide a theoretical basis and a promising technical approach for reduction of PV allergenicities.

Development and Characterization of Soy Protein Isolate/Xylose Film

This paper used different concentrations of xylose as a cross‐linker to initiate the Maillard reaction with the soy protein isolate matrix. The mechanical performance and moisture resistance of the soy protein isolate film were enhanced. Measuring the specific wavelength absorbance, free amino group concentration, and fluorescence spectrum of the cross‐linked result revealed the alteration of the soy protein isolate. Simultaneously, composite films made by crosslinking soy protein isolate with xylose were thoroughly investigated. Mechanical properties, contact angle measurement, water vapour transmission rate, optical properties, and thermal performance were used to determine the film’s fundamental properties, and the interaction relationship between soy protein isolate, xylose, and glycerol was studied using infrared spectroscopy. The study found that the modified SPI film outperformed the unmodified film, particularly when the xylose content was 20%. The tensile strength reached 6.26 MPa, and the water vapour permeability was reduced to 5.45 × 10−8 g·mm/m2·s·Pa. It also exhibited excellent UV resistance and good thermal stability.

Digestive properties and peptide profiles exhibited significant differences between skim camel milk and bovine milk powder after static in vitro simulated infant gastrointestinal digestion

This study aims to analyze the differences in digestion properties and peptide profiles between the skim camel and bovine milk powder after static in vitro simulated infant gastrointestinal digestion. The hydrolysis degree of camel milk proteins exceeded by 13.18% that of bovine milk. The concentration and release rate of free amino groups in the camel milk digesta was higher than that of bovine milk powder, which was likely due to the higher β-/αs-casein ratio and larger casein micelle size in camel milk. Camel milk powder presented higher β-CN coverage and comparatively shorter bioactive peptides compared to bovine milk powder. The anti-inflammatory peptide KVLPVPQ displayed the highest abundance in camel milk powder. Outcomes of this study showed that camel milk proteins possessed superior digestibility and unique peptides, which outlined the potential nutritional implications of camel milk for infants.

Effects of Baking and Frying on the Protein Oxidation of Wheat Dough.

Protein oxidation caused by food processing is harmful to human health. A large number of studies have focused on the effects of hot processing on protein oxidation of meat products. As an important protein source for human beings, the effects of hot processing on protein oxidation in flour products are also worthy of further study. This study investigated the influences on the protein oxidation of wheat dough under baking (0-30 min, 200 °C or 20 min, 80-230 °C) and frying (0-18 min, 180 °C or 10 min, 140-200 °C). With the increase in baking and frying time and temperature, we found that the color of the dough deepened, the secondary structure of the protein changed from α-helix to β-sheet and β-turn, the content of carbonyl and advanced glycation end products (AGEs) increased, and the content of free sulfhydryl (SH) and free amino groups decreased. Furthermore, baking and frying resulted in a decrease in some special amino acid components in the dough, and an increase in the content of amino acid oxidation products, dityrosine, kynurenine, and N'-formylkynurenine. Moreover, the nutritional value evaluation results showed that excessive baking and frying reduced the free radical scavenging rate and digestibility of the dough. These results suggest that frying and baking can cause protein oxidation in the dough, resulting in the accumulation of protein oxidation products and decreased nutritional value. Therefore, it is necessary to reduce excessive processing or take reasonable intervention measures to reduce the effects of thermal processing on protein oxidation of flour products.