天然白桦树液中污染微生物的分离与控制

本文以天然白桦树液为材料,对其污染微生物进行了分离培养和初步鉴定,从而基本搞清了污染微生物的种类与数量。发现,天然桦树原汁及其饮料中有数量不同的细菌、酵母菌、霉菌及放线菌的污染。其中,霉菌居多,酵母、细菌次之,放线菌最少。 在弄清污染微生物分布的基础上,作者研究比较了几种控制灭活微生物的方法。其中pH2.0的酸性处理未能灭活全部污染微生物,而采用90℃加热杀菌的办法以及膜板过滤技术均可达到理想的结果。 作者还根据试验结果分析探讨了微生物控制中pH值、温度、水份和环境等与微生物生长繁殖存活间的关系。从而为如何研究和解决饮料中微生物污染问题提供了有用的资料和可行的方法。

The Isolation and Regulation about Contaminate Microbials in Natural Asian White birch Juice

The materials oi the thesis were juice of natural Asian White birch. By isolation and primary identification, it was clear that the numbers and species of the contaminate microorganisms which including bacteria, yeasts, molds and actinomycetes. The number of molds was the most, however, the number of actinomycetes was the lest. On the base of the work, we also comparatively studied several contro-iing methods to kill microbials in which the proceeding by acid in pH2.0 can not kill cantaminate microbials completely, neverthless, it was satisfied result through the method of thermol-proceeding and membrane filtration. We also discussed the relationship about pH, temperature, water and environmental factors with the growth and reproduction of microbials by analysing the expermental results in order to - look for some useful reference materials and suitable methods for study and resolving contaminate problems in beverage.