烘焙时间对云南小粒咖啡挥发性成分影响的研究

Effect of Roasting Time on Volatile Components in Yunnan Arabica Coffee

摘要:

本文研究了云南小粒咖啡在烘焙过程中挥发性成分及含量的变化。在230 ℃烘焙温度条件下，对不同烘焙时间的小粒咖啡采样，采用两种方法对样品进行分析：一、同时蒸馏萃取法提取挥发性成分，采用了气相色谱-质谱联用仪对云南小粒咖啡中的挥发性成分进行了分析检测；二、顶空直接进样，气相色谱-质谱联用仪进行分析检测。对数据进行了定性定量分析、以及聚类分析。方法一分析了160种挥发性化合物，方法二分析了15种挥发性化合物。从数据可以看出，咖啡在此温度条件下，烘焙6 min后，咖啡的主要挥发性成分已经产生，如：2-甲基吡嗪、糠醇、5-甲基呋喃醛、2-乙基-5-甲基吡嗪等。随着烘焙时间增加，咖啡中的挥发性成分种类及含量变化明显。经过聚类分析可以看出，可以分为4类，可以作为判别咖啡烘焙程度一个方法。

Abstract:

Changes in the composition and content of volatile components in Yunnan Arabica coffee during roasting were studied. At a baking temperature of 230 ℃, the coffee was sampled at different baking times. Two analysis methods were used. Specifically, method one involved the simultaneous distillation and extraction of volatile components, and utilized gas chromatography - mass spectrometry (GC-MS) to analyze volatile components in Yunnan Arabica coffee. Method two involved headspace direct sampling with GC-MS analysis. The data in this study were analyzed quantitatively and qualitatively, and by cluster analysis. In the first method, a total of 160 kinds of volatile compounds were analyzed, and in the second method, 15 volatile compounds were analyzed. The data revealed that after baking for 6 min at 230 ℃, volatile components such as 2-methyl pyrazine, furfuryl alcohol, 5-methyl-furan-aldehyde, and 2-ethyl-5-methyl-pyrazine were produced. Changes in the identity of the volatile components and their content in coffee were significant with increased baking time. According to the cluster analysis, coffee roasting time could be divided into four categories, and it could be used as a way to identify degree of coffee roasting.