摘要
针对目前我国高效直投式发酵剂技术水平落后以及在应用中普遍存在酸奶后酸化的问题,研制开发具有自主知识产权的弱后酸化高效直投式发酵剂,势在必行。本文采用自行选育的弱后酸化保加利亚乳杆菌Lb-s1 rp-1为出发菌株,在优化的胡萝卜汁复合增菌培养基上增殖培养。首先研究了培养温度、培养方式、培养基起始pH值、接种量等单因素对弱后酸化菌株生长的影响,然后通过L9(33)正交试验优化了摇瓶分批式培养的增菌工艺条件;通过50 L发酵罐分批补料式扩大培养试验,并以分批式扩大培养为对照,研究了调节pH值、流加葡萄糖补料以及调节pH值且流加葡萄糖补料对弱后酸化菌株生长的影响。结果表明,弱后酸化保加利亚乳杆菌Lb-s1 rp-1实验室摇瓶分批式培养的最适增菌工艺条件:培养温度37℃,培养基起始pH 6.5,接菌量1.0%,静置培养,在此工艺条件下培养该菌株,6 h到达对数生长末期,稳定期活菌数为2.28×10^(10)CFU/mL。在50 L发酵罐中,3种补料方式培养菌株到达对数生长末期的时间分别是8,6,8 h,稳定期活菌数分别为2.29×10^(10),2.39×10^(10),2.48×10^(10)CFU/mL,与分批式扩大培养的活菌数差异不显著(P>0.05)。因此,采用50 L发酵罐分批式扩大培养弱后酸化保加利亚乳杆菌Lb-s1 rp-1的工艺是可行的。本研究为工业化生产弱后酸化保加利亚乳杆菌高效直投式酸奶发酵剂提供了细胞廉价增殖培养技术,也为研究其它弱后酸化益生乳酸菌的细胞培养技术提供了参考借鉴。
In view of the current backward technical level of high-efficiency direct-injection starter in China and the widespread problem of yoghurt post-acidification in applications,it is imperative to develop a weak post-acidification high-efficiency direct-injection starter with independent intellectual property rights.In this paper,the self-selected weak post-acidification Lactobacillus bulgaricus Lb-s1 rp-1 was used as the starting strain,and the proliferation culture was carried out on an optimized carrot juice complex bacteria culture medium.Firstly,the effects of single factors such as culture temperature,culture method,initial pH value of medium and inoculation amount on the growth of weak post-acidification strains were studied,and then the fermentation conditions of batch culture in shake flasks were optimized by L9(33) orthogonal experiment.The effects of pH adjustment,glucose feed supplementation,both pH adjustment and glucose feed supplementation on the growth of weak post-acidification strains were studied through expansion culture experiment in 50 L fermenter with batch expansion culture as a control.The results showed that the optimal bacterial growth conditions for the weak post-acidification Lactobacillus bulgaricus Lb-s1 rp-1 in laboratory shake flask batch culture were:the culture temperature was 37 ℃,the initial pH of the medium was 6.5,and the amount of inoculation was 1.0%,static culture,under which process condition the strain was cultured,the time to reach the end of logarithmic growth was 6 h,and the number of live bacteria in the stationary phase was 2.28 ×10^(10) CFU/mL.The strains were cultured in three different feeding methods in 50 L fermenter.The time to reach the end of logarithmic growth was 8,6 h,and 8 h,respectively and the number of live bacteria in the stationary phase was 2.29 ×10^(10),2.39 ×10^(10),2.48 ×10^(10) CFU/mL,which was not significantly different from the number of live bacteria in batch expansion culture(P >0.05).Therefore,it is feasible to expand the cultivation
作者
赵丽娜
巩俊明
张娜
李晨
田洪涛
王妙姝
康红艳
罗云波
Zhao Lina;Gong Junming;Zhang Na;Li Chen;Tian Hongtao;Wang Miaoshu;Kang Hongyan;Luo Yunbo(College of Food Science and Technology,Agricultural University of Hebei,Baoding 071001,Hebei;National Northern Mountain Areas Agricultural Engineering and Technology Research Center,Baoding 071001,Hebei;College of Biochemical and Environmental Engineering,Baoding University,Baoding 071001,Hebei;Hebei New Hope Tianxiang Dairy Co.Ltd,Baoding 071001,Hebei;Hebei Technology Innovation Center of Probiotic Functional Dairy Product,Baoding 071001,Hebei;College of Food Science and Nutritional Engineering,China Agricultural University,Beijing 100083)
出处
《中国食品学报》
EI
CAS
CSCD
北大核心
2022年第1期98-107,共10页
Journal of Chinese Institute Of Food Science and Technology
基金
国家自然科学基金项目(31501417)
河北省农业科技成果转化项目(16822807D)
河北省重点研发计划项目(19227134D)。
关键词
弱后酸化保加利亚乳杆菌
摇瓶
增菌工艺
50
L发酵罐
扩大培养
weak post-acidification Lactobacillus bulgaricus
shake bottle
bacterial enrichment process
50 L fermenter
expanded culture
