The usaul contaminate in beer are bacterium,fungus and wild yeast, most of them are anaerobion causing the muddy, flavor chaging and turning sour, Beer anaerobic culture medium should be found out.
中污染的常见
有细
、霉
、
母
,但主要存在危害性较大的
是细
中的大部分厌氧
,会使
浑浊、变味、变酸等。