【摘要】 以啤酒酿造生产菌株啤酒酵母(Saccharomyces cerevisiae)FB作为出发菌株,用甲基磺酸乙酯(EMS)诱变,经分离筛选得到一株优良的啤酒酵母菌株BEZ112。该菌株的絮凝性、发酵度、酒精度、发酵液的总酯和总高级醇的含量等特性保持了亲株的优良性状。但以12°Bx麦芽汁为培养基用500mL三角瓶在12℃下发酵,该菌株发酵至第4d,发酵液中的双乙酰含量达到峰值(0.291mg/L),比出发菌株FB发酵4d的峰值降低了30％,发酵至第8d,BEZ112发酵液中的双乙酰含量比出发菌株FB的降低了23％。以12°Bx麦芽汁为培养基用500L罐在12℃下发酵8d,BEZ112发酵液中的双乙酰含量(0.091mg/L)比出发菌株FB的(0.124mg/L)降低了27％。发酵得到的啤酒口感纯正清爽。更多还原

【Abstract】 After treatment with ethyl methane sulfonate (EMS) and selection, the strain Saccharomyces cerevisiae BEZ112 was obtained from Saccharomyces cerevisiae FB for beer brewage production. Some physical properties were measured. The results showed that flocculence, real degree of fermentation, alcoholicity, esters and higher alcohols of strain BEZ112 were much the same to the original strain. Change of diacetyl content in the fermented liquid during the fermentation was investigated in 500mL flask with 300mL 12°Bx wort at 12℃ . The results indicated that the diacetyl content in die fermented liquid of strain BEZ112 and original strain FB were both the highest in the fourth day, but diacetyl content in die fermented liquid of strain BEZ112 (0. 291mg/L) was 30% lower than that of original strain FB (0.4142mg/L). In the eighth day, the diacetyl content in the fermented liquid of BEZ112 was 0.096mg/L, 23 % lower than that of its original strain FB(0. 1233mg/L). The diacetyl content in the fermented liquid of BEZ112 in 500L fermentor with 400L 12°Bx wort at 12℃ for 8 days was 0. 091mg/L, 27% lower than that of the original strain FB (0.124mg/L). The sensory evaluation of the beer produced by strain BEZ112 was nice.更多还原