大豆蛋白水解物促乳酸菌增殖发酵的研究

Study on soy protein promoting proliferation fermention of lactic acid bacteria

应用小型生物发酵罐对乳酸菌增殖作用进行发酵研究,结果表明,12g/100mL脱脂乳中添加大豆蛋白水解物增殖复合剂对嗜热链球菌和保加利亚乳杆菌生长具有显著的促进作用。添加酵母膏脱脂乳培养基的产酸量比脱脂乳增加1倍,添加增殖复合剂后为脱脂乳的3.12倍。添加增殖复合剂可使乳酸菌数量达到10个数量级,比脱脂乳培养基提高1～2个数量级。从累积添加碱量和单位加碱量两项指标来看,脱脂乳培养基乳酸菌生长呈现缓慢上升曲线,添加酵母膏呈现三段波浪式曲线,添加增殖复合剂为陡峭的上升曲线。单纯添加酵母膏不能支持乳酸菌连续生长,添加大豆蛋白水解物和酵母膏能够使乳酸菌生长快速启动,并维持一个较高生长水平,获得较大的细胞量的同时也充分利用乳中蛋白质。

The fermentation tests of proliferation on lactic acid bacteria（LAB） was carried out in bioreactor,the results showed that growth of Streptococcus thermophilus and Lactobacillus bulgaricus were significantly promoted in 12g/100mL skim milk supplemented with soy protein hydrolysates（SPH）. The acid production of LAB on nonfat milk supplemented with yeast extracts and multiplication complex were 2 and 3.12 times than that of control. Then the cell count of LAB reached to 101g cycle on skim milk supplemented with multiplication complex,which increased 1.0-2.01g cycle than control. The parameter of accumulate additional alkali volume and interval additional alkali volume showed that the growth curve of LAB on skim milk ascend slowly,and three waves trend as supplemented with yeast extract,and went up dramatically with addition of multiplication complex. The addition of yeast extract alone can not support the continual growth of LAB, however,the addition of yeast extract and protein hydrolytes together can accelerate it and made it to keep in a high growth level. Much more biomass of LAB on milk with multiplication complex would be obtained and the protein in milk would be utilized sufficiently.