增溶预处理对面筋蛋白功能性质和酶解效率的影响

Improving Functional Property of Wheat Gluten by Water Solubility Enhancement

采用低浓度尿素和添加少量乙醇对小麦面筋蛋白进行预处理,旨在提高其溶解性,改善其功能性质以及酶解特性,从而拓宽应用范围。结果表明:尿素预处理使面筋蛋白质溶解度从8%提高到45%左右,尿素-乙醇预处理提高到40%,乙醇预处理提高到38.8%。乙醇、尿素预处理均利于水解度的提高,尿素-乙醇预处理则不利于水解度的提高。各种预处理对其起泡性都有显著提高,尿素对泡沫稳定性的改善效果显著,60 min后仍维持有80%以上的起始泡沫体积,而对乳化性和乳化稳定性的改善作用次于未处理的。酶解产物螯合亚铁离子能力结果表明预处理能显著提高其螯合能力,水解度(DH)越大螯合能力越大。DH 15%的酶解产物中,0.5 mol/L尿素预处理5 h结果最佳,提高至92.3%。

The water - insolubility of gluten is a major limitation for its extensive use in food processing. To improve gluten solubility, three kinds of pretreatment on wheat gluten were conducted before enzymatic hydrolysis, including addition of urea, addition of （ urea ＋ ethanol）, and addition of ethanol. The solubility, functional properties, hydrolytic efficiency of hydrolysis were compared and the Fe2＋ - chelation ability of the hydrolysates were determined. Results： Solubility values are figured out as urea pretreatment 45%, ethanol pretreatment 38.8%, addition of urea and ethanol 40%, original gluten 8%. These pretreatments lead remarkable improvement of foaming ability of gluten suspension compared with original gluten. The emulsifying property of gluten hydrolysate after pretreatment is lower than that of gluten hydrolysate without pretreatment. The Fe2＋ - chelation ability of gluten hydrolysate after pretreatment shows obvious promotion.