本文研究了大豆蛋白酶解产物（Soy protein hydrolysate，SPH）对187、495和885三种发酵剂酸奶发酵过程中pH值变化和贮藏过程中乳清析出、流变特性和质构特性的影响。结果表明，SPH对3种酸奶均具有一定的促发酵效果，其中对以187和495为发酵剂的pH值下降速度较慢的酸奶促发酵效果更明显。贮藏过程中，SPH可有效减缓酸奶乳清析出，其中对以885为发酵剂的乳清析出率最高的酸奶作用最明显，降低率达到49.35%。此外，SPH可有效提高187和495发酵剂酸奶的表观黏度和触变环面积，有利于酸奶结构的恢复。通过对酸奶第7 d流变和质构特性的进一步研究，SPH可显著提高3种酸奶的稠度和零剪切黏度，降低其流动指数、柔量和粘性指数，从而有效改善3种酸奶的流变和质构特性，提高酸奶在低应力下稳定性，降低其在高应力下形变破坏程度。

Yoghurts were fermented using different starter cultures (187, 495, or 885) for examination of the influence of soy protein hydrolysates (SPHs) on the fermentation pH and whey precipitation, as well as rheological and textural properties of the fermented products during storage. SPHs had a definite effect on the stimulation of fermentation of the three yoghurts, especially on those fermented by cultures 187 and 495 that had a lower pH reduction rate during fermentation. In storage, SPHs could effectively slow whey precipitation in the three yoghurts, where the most significant effect (reduction rate: 49.35%) was found in the yoghurt fermented by culture 885, which had the highest whey precipitation rate among the three control groups. Moreover, SPHs could greatly increase the apparent viscosity and hysteresis area of the three yoghurt samples, contributing to their structure recovery. Through further investigation of the yoghurts on the 7th day of storage, the SPH was found to have significantly improved the consistency and zero-shear viscosity of the three yoghurts, and reduced their flow behavior index, compliance value, and viscous index, thus improving their rheological and textural properties, increasing their stability under low stress, and reducing the degree of damage caused by deformation under high stress.

广州市南沙区科技计划项目（2014KF07）