啤酒酵母菌种的优劣在啤酒酿造生产中起着至关重要的作用.为了获得优良的啤酒酿造酵母菌株,试验用半导体激光诱变处理啤酒酵母(Saccharomyces cerevisiae)菌株XB05,在含双乙酰的麦芽汁琼脂平板上分离抗双乙酰的突变株,然后用三角瓶在低温下发酵,以发酵液的发酵度、双乙酰、乙醛和总高级醇的含量为筛选指标,结果得到一株发酵特性优良的菌株JW1-3.菌株JW1-3以9°Bx麦芽汁为培养基,用500 L发酵罐在12℃下发酵13 d,发酵液的发酵度为67.8%,发酵液中的双乙酰、乙醛和总高级醇的含量分别为0.039 4、4.81和60.2 mg/L.菌株JW1-3的主要发酵特性优良且稳定,啤酒口感良好.该菌株在啤酒生产中具有很好的应用前景.Beer is one of the most popular drink at present,and the yeast strain plays a key role on the beer brewing.In order to obtain the fine brewer′s yeast strain,Saccharomyces cerevisiae strain XB05 was radiated by semiconductor laser(wavelength:630 nm;power:1 w) for 10,20 and 30 min.The mono-colonies growing on wort plate agar containing diacetyl 135 μg/mL were isolated.The anti-diacetyl mutants were fermented in 500 mL flask with 300 mL wort at 12℃ for 8 d and selected with the fermented degree and the content of diacetyl,acetaldehyde and total higher alcohols of the fermented liquid as the main target.As a result,the fine strain JW1-3 was obtained.Under the conditions of 500 L fermentor with 400 L 9°Bx wort at 12℃ for 13 d,the fermented degree of mutant JW1-3 was 67.8%,the content of diacetyl,acetaldehyde and total higher alcohols in the fermented liquid were 0.039 4,4.81 and 60.2 mg/L,respectively.The fermented properties of the mutant JW1-3 were relatively stable.The sensory evaluation of the beer produced by the mutant strain JW1-3 was nice.Strain JW1-3 is of well applied prospect on the beer brewing.福建雪津啤酒有限公司资
