黄浆水酯化液工艺优化及关键风味物质分析

Optimized esterifying process of yellow water and analysis of key flavor substances

为了提高白酒副产物黄浆水的利用价值,观察酯化前后的风味变化,达到资源回收利用的目的。以洋河浓香型白酒黄浆水为原料,添加酒精、催化剂对有机酸进行酯化。比较了2种催化剂:红曲粉和H^+交换树脂的催化性能;采用红曲粉为催化剂,对酯化条件进行了单因素和正交实验;采用顶空固相微萃取(headspace solid-phase microextraction,HS-SPME)对酯化前后风味物质进行了检测。相同条件下红曲粉对总酯增加量高于H^+交换树脂;洋河酒黄浆水优化酯化条件为:无水乙醇13%(体积分数),红曲粉8%(质量分数),温度31℃,酯化时间28 d,此条件下总酯增幅较高且较为经济,总酯质量浓度由1.49 g/L增加到9.72 g/L;酯化后白酒相关风味物质(如己酸乙酯、辛酸乙酯等)均有较大提高,与洋河天之蓝白酒相比,关键风味酯类种类相似,比例接近。通过优化条件,黄浆水总酯得到有效提高,风味结构更加接近市售白酒,为黄浆水的应用提供了参照。

In order to improve the utilization of yellow water,which is a by-product of liquor making,organic acids in yellow water of Yanghe liquor were esterified by adding alcohol and catalysts.The esterification condition was optimized by single factor and orthogonal experiments using Monascus powder as a catalyst.The optimized esterification condition was found as follows:13%(V/V)anhydrous ethanol,8%(w/w)Monascus powder,reacted at 31℃for 28 d.The total ester concentration of yellow water increased from 1.49 g/L to 9.72 g/L under this condition.Headspace solid-phase microextraction followed by GC-MS analysis showed that liquor-related flavor substances,such as ethyl hexanoate and ethyl octanoate,in fermented yellow water were greatly improved,and their types and ratios were similar to those in YangheTianzhilan liquor.Therefore,this study lays a foundation for subsequent applications of yellow water.