【摘要】 甲醛是啤酒酵母的一种代谢产物,在啤酒发酵过程中,甲醛经历了积累和随后的还原两个阶段,通过引入甲醛峰值和谷值两个概念研究了啤酒生产过程中的一些影响甲醛积累和还原的控制,结果表明:(1)过低或过高的麦汁溶氧量均会增加甲醛的积累,在12～13mg/L的麦汁溶氧条件下甲醛积累最小。(2)低代酵母甲醛积累要少于高代酵母,并且低代酵母在后期甲醛的还原能力要高于高代酵母,酵母接种量在2×107个/ml时甲醛峰值最低。(3)相对较高的还原温度有利于甲醛还原。(4)麦汁浓度对甲醛的积累影响较大,高麦汁浓度条件下的甲醛峰值要比低麦汁浓度高出许多。(5)啤酒酿造后期延长还原时间并不能显著增加甲醛的还原量。更多还原

【Abstract】 Formaldehyde is produced by yeast metabolism. It is accumulated and then reduced during beer brewing. The peak value and valley value of formaldehyde concentration during beer brewing were employed to describe the formaldehyde accumulation and reduction in this paper. Results showed that: (1) Higher peak value was gained when the dissolved oxygen concentration is too high or too low in the wort. The optimal concentration of dissolved oxygen in wort for less formaldehyde accumulation is 12～13mg/L. Lower peak value or valley value is gained by brewing with lower generation yeasts inoculated. (2) The optimal inoculum size for less formaldehyde accumulation is about 2×107 cell/ml. (3)More formaldehyde is reduced with higher reduction temperature. (4)The original extract concentration in wort affects the formaldehyde metabolism. Higher original extract concentration results more formaldehyde accumulated during beer brewing. (5)It has little effect on the formaldehyde reduction by prolonging the reduction time.更多还原