薏米牛乳混合基料发酵酸奶的研制

PROCESSING OF YOGHURT WITH COIX LACRYMAJOBI AND DAIRY MILK AS FERMENTATION MATERIALS

以酶解的薏米液和生鲜牛乳的混合料液为发酵基质,接种保加利亚乳杆菌和嗜热链球菌进行乳酸发酵生产薏米牛乳酸奶。研究了发酵过程中pH值、酸度、糖分、乳酸菌数量的变化规律。随着发酵时间的增加,发酵基料的pH值不断下降,酸度增加,糖分含量下降,乳酸菌的数量呈对数增加;发酵16h产品的pH值为4.2,乳酸含量为3.4g/L,残糖为1.3%,乳酸菌的数量为6.5×108。发酵过程产生的乳酸可以使牛乳酪蛋白充分凝固,酸奶具有良好的质构和薏米焙烤的芳香气味。

Lactic acid bacteria （LAB）, Lactobacillus delbrueckii subsp. Bulgaricus DSM20081 and S. ther-mophilus DSM20031, were tested for fermentation characteristics in an -based and dairy milk medium, pH, lactic acid production, sugar content and viable counts were the parameters investigated. In general, lactic acid content and viability of LAB improved in the yoghurt product with the increase fermentation time, while pH and sugar content decreased. The parameters investigated in the final product were 4.2, 3.4 g/L, 1.3 %, respectively. The product had a better texture and flavour.