咖啡香气的超临界CO2抽提液的经时变化研究

对焙煎咖啡的超临界ＣＯ２抽提液中挥发性成分的经时变化规律研究表明，咖啡香气物质主要由沸点较低的、气相色谱保留时间约２３ｍｉｎ以下的低沸点组分组成，约占抽出的易挥发物总量的７０％。沸点较高，气相色谱保留时间在２３ｍｉｎ以上的高沸点组分约占３０％。

A STUDY ON THE VARIATIONS OF THE AROMATICS OF COFFEE

By GC method.we studied the aromatics of tbe CO_2 Super fluid Extracts (SFE)from the roasted coffee.and their variations versus the standing time. Results show thatthe aroma of coffee is mainly composed of those matters of low boiling point and with GC retention time shorter than 23min They constitute 70%or more of the total essence. There are roughly two catogories of aromatics one is that with GC retention time short-er than 23min the other is that of low boiling point.The former decreases rqpidly as theadvancing.of the standingtime and no new substances are observed.However,the later re-mains relatively constant.and new substances are observed. The variations above maysuggest the onset of the flavor loss.