本实验采用乳清蛋白制备了一种不添加稳定剂的酸奶，为制作无添加剂酸奶提供理论依据。通过分析不同添加量的乳清蛋白对酸奶发酵终点，以及后熟和保质期内酸奶的酸度、粘度、脱水收缩作用敏感性(STS)、持水率(WHC)的影响，结果发现：乳清蛋白对发酵终点的影响不大；随着乳清蛋白添加量的增加，在后熟时酸奶的酸度变化加快；乳清蛋白可以提高酸奶在保质期内的稳定性，对STS和WHC都有促进作用，可保证产品最终质量。此外，结合感官测评，乳清蛋白添加量在3~4%时，产品口感及稳定性较佳，通过使用乳清蛋白可以使无添加剂的酸奶在保质期内稳定。

In this experiment, whey protein YO-5011 was added to produce yoghurt without stabilization additives. Different quantity of whey protein was added to observe its effect on the yoghurt fermentation end point, as well as the titratable acidity, viscosity, STS, WHC during post fermentation and self-life time. The result showed the effect of the addition quantity of whey protein on the fermentation end point was not significant. The more whey protein added, the more rapidly titratable acidity increased. Whey protein enhanced the yoghurt stability during self-life time and improves STS and WHC which guaranteed the final product quality. Besides, combined with the result of additional sensory testing, the product taste and stability was optimized with a 3~4% whey protein addition.

?国家科技部973计划（2010CB735705）