不同烘焙程度云南小粒咖啡类黑精中挥发性成分分析

Analyzing volatile components in coffee melanoidins from different roasting-degree Yunnan Arabica coffee melanoidins

目的研究不同烘焙程度云南小粒咖啡类黑精中挥发性成分及含量的差异。方法采用热水提取法从不同烘焙度云南小粒咖啡中提取类黑精,并用二氯甲烷超声萃取法对其挥发性成分进行萃取,采用气相色谱-质谱联用仪对云南小粒咖啡类黑精中的挥发性成分及其含量进行分析检测。结果云南小粒咖啡类黑精的含量随咖啡豆烘焙度的增加而增加。从浅、中、深3种烘焙度的云南小粒咖啡类黑精中分别鉴别出37种、45种、46种化合物,其中糠醇、糠醛、5-羟甲基糠醛、咖啡因、六氢-3-(异丁基)-吡咯并[1,2-a]吡嗪-1,4-二酮含量较高,但在不同烘焙条件下各化合物的含量不同。结论 3种烘焙度的云南小粒咖啡类黑精中的挥发性成分均含有大量的糠醇、糠醛、呋喃、吡嗪、吡咯、酚类等化合物,但含量不同,其中糠醇及糠醛的含量随烘焙度的增加而增加。

Objective To analyze the difference of volatile components and its contents in different roasting - degree Yunnan Arabica coffee melanoidins volatile. Methods The melanoidins from different roasting - degrees Yunnan Arabica were extrac- ted by hot water extraction method. The volatile components of each sample were extracted by ultrasonic extraction with dichlo- romethane. The volatile component and content of the extracts were analyzed and detected by gas chromatography - mass spec- trometry（ GC -MS）. Results The melanoidins content, which were extracted from different roasting- degrees Yunnan Arabi- ca, increased with the degrees of roast increasing. 37 volatile components, 45 volatile components and 46 volatile components from light - roasting - degree, middle - roasting - degree and dark - roasting - degree Yunnan Arabica coffee melanoidins were identified, respectively. 2 - Furanmethanol, furfural, 5 - Hydroxymethylfurfural, caffeine, hexahydro - 3 - （isobutyl） - 1, [ 2 - a] - pyrazine - 1,4 - dione accounted for the majority proportion among those components, while the content was different in different baking conditions. Conclusion All of the volatile components in coffee melanoidin of 3 roasting - degree Yunnan Arabica contains plentiful 2 - Furanmethanol, furfural, furan, pyrazine, pyrrole, phenolic, whereas their contents were differ- ent. Among them, the content of 2 - Furanmethanol and furfural increase with the degree of roast increasing.