小麦低聚肽制备凝固型酸奶及其发酵特性的研究

Preparation of Solidified Yogurt by Wheat Oligopeptide and its Fermentation Characteristics

选取3种酶(胃蛋白酶、碱性蛋白酶和风味蛋白酶)对谷朊粉进行水解,将不同酶解时间得到的小麦低聚肽加入酸奶中,代替部分牛奶蛋白(3%),以酸奶的pH值、滴定酸度为指标进行感官评价及质构分析,筛选出促酸奶发酵能力较好的酶解物,然后将小麦低聚肽按分子质量进行超滤膜分离,并评价和比较不同肽段的促酸奶发酵能力。结果表明,用碱性蛋白酶水解小麦面筋蛋白24 h的小麦低聚肽促酸奶发酵能力最佳,其中分子质量为1.5~3.5 kU的肽段极大地缩短酸奶的发酵周期,改善了酸奶的感官结构特性。

Firstly,alkaline protease,pepsin and flavourzyme were selected to hydrolyze wheat gluten at different time.Then,the hydrolysates with different enzymolysis time were added to yogurt to replace part of milk protein(3%).The hydrolysates with the best enzymolysis time for yogurt fermentation were screened out by pH and titratable acidity of fermented yogurt.Then,the hydrolysates with the best enzymolysis time were freeze-dried into powder to replace part of milk powder to ferment yogurt.Through comprehensive sensory evaluation,physical and chemical analysis and texture analysis,the hydrolysate with the best fermentation ability of yogurt was screened out.The results showed that the wheat oligopeptide hydrolyzed wheat gluten protein for 24 h with alkaline protease had the best ability to promote the fermentation of yogurt,and the peptides with molecular weight ranging from 1.5~3.5 kU greatly shortened the fermentation cycle of yogurt and improved the sensory structure characteristics of yogurt.