摘要
对Lactobacillus rhamnosus grx19的热应激作用进行了研究,发现L.rhamnosus grx19在65℃和72℃的D值分别为48.5和25.3,该菌在脱脂乳中经10h培养后,在52℃热激60min,菌株在72℃/15s热处理的存活率从未经热应激处理的46.0%提高到56.0%。热应激处理导致L.rhamnosus grx19在脱脂乳中37℃发酵24h的平均产酸速率下降了36.3%,且制备的发酵乳产品在4℃/30d的贮藏过程中,后酸化速率下降了26.5%。
The heat stress of Lactobacillus rhamnosus grx19 was studied. The results show that the D value of L. rhamnosus grx19 at 65 ℃ and 72 ℃ was 48.5 and 25.3 respectively. The best heat stress condition to improve thermoduric properties was the strains cultured in skim milk for 10 h, and heat stressed in 52 ℃ for 60 min. The survival rate of heat shock L. rhamnosus grx19 strains treated 15 s at 72 ℃ reached to 56.0%, whereas the strains without heat stress was only 46.0%. Heat stress result in the fall of strains ferment producing acid and postacidification ability, that the average acid yield rate of skim milk inoculated the heat stress strains was dropped to 36.3% for 24 h fermentation. Meanwhile, the postacidification ability of the fermented milk inoculated this heat stress of L. rhamnosus grx19 was dropped to 26.5% during storage at 4 ℃ for 30 days.
出处
《食品科技》
CAS
北大核心
2013年第8期2-5,共4页
Food Science and Technology
基金
江苏高校优势学科建设工程项目
江苏省科技支撑项目(BE2011383)
关键词
鼠李糖乳杆菌
热应激
耐热特性
L. rhamnosus
heat stress
thermoduric properties
