【作者】 徐立荣；

【导师】 熊涛； 曾哲灵；

【作者基本信息】 南昌大学 ， 食品科学， 2007， 硕士

【摘要】 泡菜、酸菜、酱油、豆豉等都是一种具有悠久历史的大众发酵蔬菜制品，其制作工艺可以追溯到2000多年前。发酵蔬菜以其酸鲜纯正、脆嫩芳香、清爽可口、回味悠久、解腻开胃的品位及功效越来越为各国人民喜欢。发酵蔬菜作为一种传统的健康食品，其营养和保健功效越来越引起人们的关注。乳酸菌是发酵蔬菜生产中的主要生产菌株，筛选适合于蔬菜发酵的专用乳酸菌种是缩短蔬菜发酵生产周期、稳定产品质量和提高食品安全性的关键。提高蔬菜发酵速率、缩短直投式泡菜发酵时间、减少甚至防止亚硝酸盐产生的关键是提高蔬菜发酵专用复合菌粉中的活菌数，而制备蔬菜发酵专用复合菌粉的关键环节是菌体高密度培养。本文主要进行以下方面的研究：(1)从蔬菜发酵老液出发，有目的地筛选到3株菌，经形态特征和生理生化特征鉴定均为乳酸菌。(2)对筛选到的乳酸菌进行蔬菜发酵性能研究：其中菌株编号NCU0101在发酵24h后，发酵液pH值达到3.39、酸度达到0.63g乳酸／100mL、菌落数达到1.25×10~9cfu／mL的高密度富集状态。(3)采用缓冲盐法、化学中和法和补料培养法进行乳酸菌NCU0101的菌体高密度培养，分析研究培养基配方、培养条件、补料培养方式对菌体活菌数的影响。结果表明：菌体适宜培养基配方为葡萄糖5％、蛋白胨1％、磷酸氢二钾0.5％、醋酸钠0.3％，适宜培养条件为培养液pH值6.3～5.8、培养温度30℃、振荡频率40r／min、培养时间20h，适宜补料培养方式为培养0h、4h和8h时各补加2.5％的碳氮源(碳氮比为5：1)；培养结束后，培养液中乳酸菌菌体活菌数可达7.83×10~9cfu／mL。更多还原

【Abstract】 All of pickles, sour pickled cabbage,sauce, bean are a kind of public which have a long history to ferment vegetable ware, which creation craft can trace back to more than 2000 years ago. Vegetable fermented is enjoyed by more and more people in all countries with sour and fresh delicate fragrance, clearness of the pure and unadulterated, frailty is tasty and enjoy in retrospect long, get fed up with solving and open personal status and effect of the stomach. Ferment is as a kind of traditional health food which nourishment and health care effect of vegetable conduct cause people more and more of concern.The lactobacillus is to fermentvegetable production in of main production germ stub, sievingthe appropriation lactobacillus suited for the vegetable ferment is the key to shorten a vegetable to ferment production period, stabilize the product quality and raise the food safety. The key which raises a vegetable to ferment velocity, shortens to keep a hurl type pickles to ferment time and reduces to even keep second nitrate from producing is to raise the live bacteria number of compounds germ powders which is appropriatd to ferment vegetable. But dense cultivation is the key to prepare concentrated bacterial powder for vegetable fermentation.Main contents discussed in this thesis are as follows:（1） Three lactobacillus strains have been screened from the original culture fluid after certain time of vegetable fermentation. Characterization of morphology and physiochemical properties has confirmed that all of them are lactobacillus.（2） The study has been conducted to identify the fermenting capacity of these strains. After fermentation for 24 hours the fermenting solution of the strain （No.NCU0101） contains the biomass of 1.25×10⁹cfu/mL, with the acidity of 0.63 g lactic acid /100mL and pH 3.39.（3） The study of high cell density culture of lactobacillus No. NCU 0101 has shown that it is feasible to achieve the goal using buffer solution, chemical neutralization and feed batch culture. It is found that medium formula, culture conditions, and feed batch methods have great impacts on biomass growth. Suitable medium formulation is: 5% glucose, 1% peptone, 0.5%K₂HPO₄, 0.3%sodium acetate. Optimal culture conditions are pH 6.3～5.8, temperature 30℃, oscillation frequency 40 r/min , and culture time 20h. Appropriate feeding culture method is that 2.5% carbon and nitrogen sources （C/N ratio is 5:1） is added respectively after Oh, 4h and 8h. With the optimal culture conditions, the number of the bacteria cells is up to 7.83×10⁹cfu/mL.更多还原