啤酒麦芽真菌种类与酵母提前絮凝关系的研究

Research of the relationship between barley fungi and Premature Yeast Flocculation

啤酒麦芽受到霉菌污染易引起酵母提前絮凝现象,为了研究引起酵母提前絮凝(PYF)现象的真菌种类,从PYF+麦芽(能够产生酵母提前絮凝现象的麦芽)上分离得到8种霉菌,分别用8种霉菌对麦芽皮壳进行处理,然后与去除皮壳的麦芽粉制备协定麦汁,煮沸,接种发酵,进行PYF值测定,最后进行数据分析。结果表明米根霉和黄曲霉为明显致PYF现象的菌种,镰刀菌为致PYF次级明显菌种,极细链格孢菌和白地霉为致PYF现象弱势菌种,芽枝孢菌和黑曲霉为轻微致PYF现象菌株,而青霉致PYF现象不稳定,这可能与菌种的量和酶活性有关,需要做进一步实验验证。

When Beer malt was infected with fungi,it would lead to premature yeast flocculation.So it is important to study the relationship between fungi and the phenomenon of Premature Yeast Flocculation （PYF）.Eight kinds of fungi were selected from PYF ＋ malt.In order to learn about the relationship between fungi and PYF,eight kinds of fungi were inoculated into the media which prepared by malt shell and distilled water, separately, and then produced wort agreement with non-shell malt and followed on boiling ,filtering, pitching yeast and testing the value of Premature Yeast Flocculation.According to the consequences about the relationship between barley fungi and Premature Yeast Flocculation,conclusions could be drawn that both rhizopus oryzae and Aspergillus flavus could apparently and heavily bring about Premature Yeast FIocculation.And Fusarium could also apparently bring about Premature Yeast FIocculation,but weaker than rhizopus oryzae and Aspergillus flavus.Geotrichum candidum and Alternaria tenuissima tend to normal fermentation.What＇s more,Aspergillus niger and cladosporium tenuissimum lightly result in Premature Yeast Flocculation.Penicillium lead to sporadic flocculation.lt might be connected with strains quantity and enzyme activity. It is necessary to deeply study.