标题：Effect of incubation time, inoculum size, temperature, pasteurization time, goat milk powder and whey powder on ACE inhibitory activity in fermented milk by L. plantarum LP69
摘要：Background. Angiotensin I converting enzyme (ACE) plays an important physiological role in regulating hypertension. Lactic acid bacteria are known to produce ACE inhibitory peptides which can lower hypertension during fermentation. Methods. The effect of incubation time (0~36 h), inoculum size (3, 4, 5, 6 and 7%, v/v), temperature (25, 30, 35, 40 and 45°C), sterilization time (5, 10, 15, 20 and 25 min), concentration of goat milk powder (8, 10, 12, 14 and 16%, w/v) and whey powder (0.5, 0.6, 0.7, 0.8 and 0.9%, w/v) on ACE inhibitory peptides fermented from goat milk by Lactobacillus plantarum LP69 was investigated using single factor experiment. Results. The optimal incubation time, inoculum size, temperature, pasteurization time, goat milk powder and whey powder in fermented milk by L. plantarum LP69 was 14 h, 3.0%, 35°C, 20 min, 14% and 0.70% for ACE inhibitory activity and 22 h, 3.0%, 40°C, 25 min, 16% and 0.60% for viable cell counts, respectively. Conclusion. The incubation time, inoculum size, temperature, pasteurization time, goat milk powder and whey powder had a signifi cant infl uence on ACE inhibitory activity in fermented milk by Lactobacillus plantarum LP69, the results are benefi cial for further screening of main factors by using fractional factorial designs.
其他关键词：ACE inhibitory peptide, goat milk, Lactobacillus plantarum, inoculum size, pasteurization time, incubation time, whey powder
