According to the physiological characteristics of Lactobacillus helveticus, the optimal fermentation condition were 2% amount of inoculation amount, 40 °C incubating temperature, initial pH 7.1 and 12 h incubating time. Under these conditions, the concentration of cell could reach 10 8-10 9- mL-1.Discussed the correlation between the characteristics of Lactobadllus helveticus and different temperatures-time combination. It was showed that heat-shock was acted below 67 ℃ or the treatment time was less than 15 s, there was no significant retardation of lactic acid production. While the treatment temperature was above 69 ℃ or the time was more than 20s, the residual intracellular enzyme activity declined sharply, with no more than 20% activity left. The heat shock temperature and time were in the range of 67-69 ℃ and 15~20 s, respectively.%根据瑞士乳杆菌生理特性,优化了其最佳生长条件:接种量2％,温度40℃,初始pH值7.1,培养时间12h.在此条件下培养,菌液浓度可达108～109mL-1.探讨了瑞士乳杆菌特性与热激温度、时间的相关性.结果表明,低于67℃或时间少于15s,对抑制细胞产酸无明显影响;高于69℃或时间超过20 s,胞内酶残留率不足20％,优化出热激条件为温度67～69℃,时间15～20s.
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