Wheat gluten is a kind of high-quality protein, rich in essential amino acids, and its large glutamate and glutamine account for about 35% of the total amino acid. However, present utilization of wheat gluten in food industry has many limitations. Because the high content of hydrophobic amino acid in wheat gluten protein would deteriorate its functional properties such as solubility and emulsification which made it difficult to be processed. Many literatures reported that both heat treatment and acid treatment can remarkably improve the solubility of proteins, and even cause structural transformation, which would make wheat gluten easier to hydrolyze. Meanwhile, glutaminase has elucidated a function of improving the protein solubility by disintegrating non covalent bonds or intermolecular disulfide bond in its hydrophobic regions. And with the interaction with pancreatin—an efficient commercial enzyme in protein hydrolysis, wheat gluten protein was expected to show a better hydrolysis efficiency. In order to explore the effects of different deamidization and double-enzyme synergism treatments on hydrolysis efficiency and antioxidant activity of wheat gluten, we took the method of double-enzyme synergetic hydrolysis combined with deamidization to obtain a kind of product with high hydrolysis efficiency as well as satisfying antioxidant property. Thus, this study took wheat gluten protein as raw material to prepare wheat gluten protein hydrolysate. And the effects of deamidization treatment and double-enzyme synergy on hydrolysis efficiency (protein recovery and degree of hydrolysis), antioxidant activity and molecular weight distribution were discussed. The products were mainly prepared by different enzyme-adding orders as well as different synergetic hydrolysis time. Results showed that the protein enzymatic sensibility of wheat gluten protein could be increased after heat treatment with 0.5 mol/L citric acid (mass ratio of citric acid to wheat gluten was 1:20), but heat treatment alone (90℃,30 min) showed no significant influence on hydrolysis efficiency. Significant difference in hydrolysis efficiency was observed when wheat gluten was prepared with the enzyme-adding order of pancreatin after glutaminase. The results also indicated that a certain time of enzymatic synergism (not longer than 12 h) was conducive to hydrolysisbut did not show positive effect when longer than 12 h whose hydrolysis efficiency was not as high as that of 7h. This article obtained an optimal hydrolysis efficiency hydrolysate of wheat gluten protein which was obtained by 12h protein-glutaminase (PG) (0.2% mass content) single-prehydrolysis and 7 h pancreatin (0.6% mass content) simultaneously hydrolysis on heat-citric acid-treated wheat gluten material. . The degree of hydrolysis achieved 9.88% and the protein recovery was 70.74%, and high content of low molecular weight products in hydrolysate was obtained according to the molecular weight distribution.. In addition, ABTS+ radical scavenging ability value and ORAC (oxygenradicalabsorbance capacity) value reached 478.95 mmol /g and 213.85μmol /g, respectively, which proved that wheat gluten protein prepared by this process was a potential good antioxidant. In conclusion, the optimal preparation can provide theoretical basis for the deep processing of wheat gluten and a guidance for preparing the products with excellent antioxidant properties.%为了探讨了不同脱酰胺处理和双酶协同作用方式对小麦面筋蛋白酶解效率及其产物抗氧化活性的影响，该文研究了小麦面筋蛋白在各种预处理方式和酶解条件下的蛋白回收率、水解度、抗氧化性能及肽分子量分布情况。结果显示，单独热处理（90℃，30 min）小麦面筋蛋白对其酶解效率无显著影响，而采用添加0.5 mol/L柠檬酸溶液进行热处理（质量分数为5%，90℃，30 min）可显著（P<0.05）提高其蛋白回收率。此外，酶制剂添加顺序及双酶共同水解作用时间对酶解效率均具有较大影响：加入谷氨酰胺酶预先水解对小麦面筋蛋白的深度水解有促进作用；一定时间内的双酶协同作用有利于酶解的进行，但较长时间的双酶作用反而会抑制酶解效率。采用谷氨酰胺酶（质量分数为0.2%）对经柠檬酸加热处理的小麦面筋蛋白作用12 h后再加入胰酶（质量分数为0.6%）共同作用7 h可使蛋白回收率达70.74%，水解度达到9.88%；另外，酶解产物的自由基清除能力 ABTS+（2,2’-Azinobis-(3-ethylbenzthiazoline-6-sulphonate)+）值与氧化自由基吸收能力（ORAC，oxygen radical absorbance capacity）值分别达到478.95 mmol/g和213.85μmol/g，提示该酶解产物是一种潜在优秀食品抗氧化剂。研究结果可为拓宽小麦面筋蛋白的应用领域，以及高效制备抗氧化活性肽提供方法和理论指导。
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