西藏“灵菇”乳的发酵与抑菌机制研究  

Mechanism of fermentation and antibacterial activity of the‘Tibetan mushroom’milk

作　　者：邵东燕[1] 杨保伟[1] 师俊玲[1] 毋锐琴[1] 张学良[1] 

机构地区：[1]西北农林科技大学食品学院,杨凌712100

出　　处：《农业工程学报》2008年第7期269-272,共4页Transactions of the Chinese Society of Agricultural Engineering

摘　　要：根据发酵过程中菌粒中主要微生物数量与发酵乳中主要营养物和产物含量间的关系,分析探讨了西藏"灵菇"乳的发酵机制;考察了不同发酵时期所得发酵乳对大肠杆菌、金黄色葡萄球菌、沙门氏菌的抑菌活性,结合化学物质模拟试验揭示了发酵乳的抑菌机制。结果显示,发酵前期,菌粒中的各微生物由于向乳中扩散及生长延滞,数量稍有减少;随着发酵的进行,菌粒中乳酸菌和酵母菌的数量一直处于相对稳定的水平,但醋酸菌含量呈明显的先升后降趋势;在整个发酵过程中,菌粒中的乳酸菌数量一直处于最高水平,其次为酵母菌,醋醋菌数量最少;乳酸是西藏"灵菇"发酵乳中的主要抑菌活性物质;乙酸和乙醇的存在对低浓度乳酸的抑菌活性有增效作用,但当乳酸浓度较高时,这种增效作用减弱。西藏"灵菇"发酵乳的总抑菌效果是微生物与其代谢产物的共同作用结果。Based onthe correlation of the number ol the dolmnating microorganisms in me solid culture of ‘Tibetan mushroom’ and me trend of nutrients：and products, mechanisms were explored for the fermentation processing and antibacterial ability of the fermented milk. Enteropathogenic. E. coli, Staphylococcus aureus and Salmonella were used as the model pathogens to investigate the antibacterial ability. Pure lactic acid, acetic acid, and ethanol were used to identify the dominate factors contributing to the antibacterial ability of the fermented milk. Results showed that the numbers of all tested microorganisms decreased in the first few hours, might due to the cells diffused from the solid culture to the milk and the slow cell growth rate. Along with the fermentation, numbers of lactic acid bacteria and yeast kept in a relative stable level, but number of acetic acid bacteria showed significant increase and then decrease. During the fermentation, number of lactic acid bacteria kept in the highest level followed by number of yeast. Acetic acid bacteria showed the lowest level in the fermentation. Lactic acid was identified as the main factor Contributing to the antibacterial ability of the ＇Tibetan mushroom＇ milk. Acetic acid and ethanol showed the ability in intensifying the antibacterial ability of lactic acid when lactic acid content was low, but the intensifying ability lowered when lactic acid at high levels. The antibacterial activity of the ‘Tibetan mushroom＇ milk is contributed to the combination of the activity of bacteria and their products.

关 键 词：西藏“灵菇” 菌粒 发酵 牛乳 抑菌活性 

分 类 号：TS252.42[轻工技术与工程—农产品加工及贮藏工程]