酪蛋白水解物对发酵乳中乳酸菌增殖作用的研究

The study on lactobacilli proliferation in fermented milk supplemented with casein hydrolysates

嗜酸乳杆菌（Lactobacillus acidophilus）是乳酸菌家族中极为重要的益生菌之一，已广泛地被人们所接受，因此，研究利用该菌于发酵酸乳制品中具有重要意义。本文采用嗜酸乳杆菌（Lactobacillus acidophilus）和嗜热链球菌（Streptococcus thermophilus）共发酵技术，较系统地研究了酸奶发酵的最佳条件，确定了酪蛋白水解物对嘈酸乳杆菌增殖有明显的促进作用并可提高其生存能力。实验结果表明，嗜酸乳杆菌：嗜热链球菌=2：1，37℃培养时，酸奶凝乳时间最短，产品质地最好。同时，水解度为25．0％酪蛋白酶解物对嗜酸乳杆菌增殖有明显的促进作用，添加2g／L，37℃培养，2h后即可凝乳，所得产品质地细腻，酸度达到80DT，终产品中嗜酸乳杆菌活菌数达到10^9cfu／mL。

Nowdays, Lactobacillus acidophilus is regarded as one of the most important probiotics in Lactobacilli and abroad accepted by people. It is significant to study LactobaciUus acidophilus used in yoghurt production. In this article, the fermentation condition of a new yoghurt fermented by Lactobacillus acidophilus and Streptococcus thermophilus was studied. The effect of casein hydrolysates on prebiotic cell counts and survival in fermented milk was researched too. The best fermentation condition was .that the ratio of Lactobacillus acidophilus and Streptococcus thermophilus was 2 tol and the fermentation temperature was 37℃. Under this condition, the fermentation time was shortest and the texture of yoghurt was best. At the same time, DH of casein hydrolysation on 25.0% had a good effective effect on the proliferation of Lactobacillus acidophilus. The concentrations was 2g/L, fermentation temperature was 37℃ and fermentation time was 2 hours. The acidity was up to 80°T and the cell counts of Lactobacillus acidophilus in fermentation products raised obviously up to 1 10^9cfu/mL.