酸马奶中干酪乳杆菌发酵特性的研究

Fermentation properties of 4 strains of Lactobacillus casei isolated from traditionally home-made koumiss in inner mongolian of China

研究了从内蒙古锡林浩特传统发酵酸马奶中分离4株(Lb.caseiZL3-1,Lb.caseiZL3-4,Lb.caseiZhang和Lb.caseiXM2-1)具有潜在益生特性的干酪乳杆菌的发酵特性。结果表明,37℃发酵24h结束后,干酪乳杆菌发酵乳滴定酸度为79.75°T,pH值变化在4.52～4.26之间。Lb.caseiZL3-1,Lb.caseiZL3-4,Lb.caseiZhang和Lb.caseiXM2-1在发酵结束的活菌总数分别为8.11×108,8.53×108,9.61×108和5.30×108mL-1,其中Lb.caseiZhang活菌数为最高。24h发酵结束时,Lb.caseiZL3-1,Lb.caseiZL3-4,Lb.caseiZhang和Lb.caseiXM2-1的黏度分别为0.1830,0.2957,0.1167和0.2497Pa.s。发酵过程中质量分数为12%的TCA可溶性氮无明显增加,4株干酪乳杆菌的蛋白水解力无显著性差异(P>0.05)。

The fermentation properties of 4 strains of Lb. casei （Lb. casei ZL 3-1, Lb. casei ZL3-4, Lb, casei Zhang and Lb. casei XM 2-1 ） isolated from traditionally home-made koumiss in Inner Mongolian of China were studied in this paper. Results showed that the average of titration acidity was 79.75 °T, pH varied within 4.52-4.26 after inoculating Lb. casei in reconstituted skim milk （11%, with 5% sucrose and 0.75% glucose ,w/v） and incubation for 24 hours at 37 ℃. At the end of 24 hour fermentation ,the living cells of Lb.casei ZL 3-1, Lb. casei ZL 3-4, Lb.casei Zhang and Lb.casei XM 2-1 were 8.11×10^8,8.53×10^8,9.61×10^8 and 5.30×10^8 cfu mL^-1 respectively. The viscosity ofLb.casei ZL 3-1, Lb.casei ZL 3-4, Lb.casei Zhang and Lb.casei XM 2-1 was 0.1830,0.2957,0.1167 and 0.2497 Pa·s. During fermentation, the changes of 12% TCA-soluble nitrogen were not evident, there was no significant difference between these 4 strains of Lb.casei for proteolvsis activities（ P〉0.05 ）.