红曲霉发酵液酯化酿酒尾水制备酯化液的研究

利用红曲霉发酵生成的酯化酶液,催化酿酒尾水中的有机酸和醇,来制备含酯量较高的酯化液。本研究采用液态发酵法制备酯化酶液,添加到酿酒尾水、乙醇、己酸的混合液中,在一定条件下进行酯化反应,以混合液总酯含量和各有效成分含量为指标,设计单因素实验考察影响酯化反应因素的范围,采用正交设计实验优化各酯化反应的条件。正交实验所得的最优条件为乙醇添加量为10%、酯化酶液添加量为9%、己酸添加量为1.5%、酯化反应温度为35℃,在此条件下混合液中总酯的含量达137.01 mg/100 mL,其中己酸乙酯含量高达222.71 mg/L,乳酸乙酯的含量由92.93 mg/L下降到74.61 mg/L,乳酸乙酯与己酸乙酯的比值小于1。所得酯化液适合用于白酒的勾调,不仅大幅提高了酒体中总酯含量,还减少了乳酸乙酯对主体香型的抑制和青涩杂味,使酒体香气更为突出协调。

Study on the Esterification Liquid Made by Wine Tail Water and the Liquid Fermented by Monascus

The esterified liquid with higher ester content was obtained by esterifying reaction between organic acid and alcohol in wine tail water,under the catalysis of esterifying enzyme,produced by liquid fermentation of monuscus. Total ester content value in the mixture,tested by the ways of titration and gas chromatography,was the main indicator to determine influencing esterifying reaction factors and scope. Single factor experiment and orthogonal test were done in the study. The result showed that,the optimization conditions were ethanol 10%,caproate 1.5%,esterifying enzgme 9%,the optimization esterifying reaction temperature 35℃.In the conditions,the total ester content in esterification liquid reached 137.01 mg/100 mL,among which the content of caproic acid ethyl ester was as high as 222.71 mg/L. The content of ethyl lactate decreased from 92.93 mg/L to 74.61 mg/L,and the ratio of ethyl lactate to ethyl hexanoate was less than 1.The esterified liquid was just fitting for liquor blending,which not only greatly increased the total ester content in the wine,but also reduced the content of ethyl lactate,reduced the inhibition of ethyl lactate on the main flavor and astringent taste,so that the aroma of wine was more prominent coordinate.