啤酒风味物质及游离脂肪酸的气相色谱研究

Gas Chromatography Studies of the Flavorous Substance and Free Fatty Acids in Beer

啤酒中含量极低、极不稳定的游离脂肪酸(FFAs)是影响啤酒风味的主要因素。实验采用气相色谱技术,对形成啤酒的主要风味(如药物味、水果味、酒精味和哈喇味等),重点是不良风味的风味物质进行了检测。啤酒样品经两次酸化处理,酯化后薄层分离的方法测得游离脂肪酸的含量具有较好的重复性和较高的回收率,以癸酸和亚油酸为代表测得回收率分别为85%和114%。

The difficult point for the flavorous substances analysis in bear by gas chromatography （GC） is that the flavorous substances, free fatty acids （FFAs）, are rare and unstable in beer. In this study several flavorous substances in beer such as drug flavor, furit flavor, alcohol flavor and Halal smell, have been examined with GC technology and the forming reasons of them were analyzed. It showed that 1-chlorophenol, ethy acetate, ethyl dodecylate, butyric acid and dedecylci acid et al. were the main flavorous substances formins the flavor of beer. A set of effective method to determine the content of FFAs with GC was also built. The samples were treated by acid-treament for twice, esterification and thin-layer chromatography. The method was of good repeatability and high recovery. The recovery of capric acid and linoleic acid was 85% and 114%, respectivety. Therefore it can well improve the quality and flavor of beer.