U．V．诱变法选育pof~－糖化酵母

ＧＹＮＢ培养基中肉桂酸浓度达到１００μｇ／ｍｌ时，酿酒酵母（Ｓａｃｃｈａｒｏｍｙｃｅｓｃｅｒｖｉｓｉａｅｐｏｆ~－ｓｔａ）的生长受到抑制，而糖化酵母（ＳａｃｃｈｒｏｍｙｃｅｓｄｉａｓｔｉｃｕｓＰＯＦ１ＳＴＡ）能够生长。用紫外线诱变糖化酵母，在ＧＹＮＢＳＣＡ１００培养基平板上检出ｐｏｆ~－糖化酵母营养缺陷株。经糊精发酵试验、模拟啤酒发酵试验、ＣＯ＿２失重试验及糖化酶活性比较，选育出三株性能优良的糖化酵母单倍体（ｐｏｆ~－ＳＴＡ），发酵速度快，糖化酶活性略低于出发菌株。发酵的啤酒用“两杯法”进行品评，酒体丰满，香气新鲜，略带果酒味，无酚臭味。

Breeding of Saccharom yces diastaticus with pof￣- by U. V. Treatment Method

Cinnamic acid(100μg/ml)incorporated in GYNBCA100 medium inhibited the growth of brewing strains(pof-) of Saccharomyces cervisiae while permitting the growth of Saccharomyces diastaticus(POF1).Ultraviolet rays eliminated POF1 gene of Saccharomyces diastaticus haploids haploids(a or α) which produce glucoamylase. pof- nutritional deficiency strains of Sac.diasdtaticus were selected on GYNBSCA100 Soild medium. After dextrin fermentation test, imitating beer fermentation trial,CO_2 loss in weight experiment and comparing glucoamylase activity test,three strains(pof- STA) were chosed which possess greater glucoamylase activity,ferment rapid and have no phenolic-off-flavour when fermented hopped wort.