Study on preservability of the Lactobacillus acidophilus fermented milk

The preservability of Lactobacillus acidophilus in fermented milk during refrigerated storage was studied.The results showed:fermented milk storaged at 7 ℃ for 14 days,the survival rate of two strains of Lactobacillus acidophilus was 3 43% and 2 20%;living cell number reached 108 mL-1;the acidity of milk was 90 °T and 107 °T;biacetyl increased by 11 80% and 56 41;and acetaldehyde was 2 993 mmol/mL and 2 561 mmol/mL respectively.The final product had good taste and flavour.