桑葚果酒发酵过程中的香气成分变化

Changes of Aroma Composition during Fermentation of Mulberry Wine

以"大什"桑葚为试材,采用顶空固相微萃取结合气相色谱质谱联用技术(HS-SPME-GC-MS),研究了桑葚果酒发酵过程中香气变化规律。结果表明:在发酵过程中共检测出67种香气物质,酯类33种、醇类4种、酸类5种、醛类8种、酚类2种、萜烯类6种、其他类9种,众多的呈香物质构成了桑葚果酒的主体香气。酯类是构成果酒香气的重要物质,如十二酸乙酯、十四酸乙酯、十六酸乙酯等,它们赋予果酒独特的香气;醇类香气中以苯乙醇为主,是发酵产生的特征性香气,也是桑葚果酒的重要香气之一;酸类香气中,以辛酸和癸酸为主,可与发酵产生的乙醇反应,生成辛酸乙酯和癸酸乙酯;醛类香气中,2-壬烯醛、2,4-壬二烯醛仅存在于第0 d中,其他醛类物质在发酵过程中不断减少;萜烯类也是桑葚发酵过程中一类重要的香气物质,如长叶烯、松油烯-4-醇、香茅醇等,但在发酵过程中含量减少,从发酵0 d的977.23μg/L,减少到发酵结束的553.82μg/L。主成分分析表明前2个主成分的累计贡献率达到91.10%,对第一主成分贡献较大的是苯乙醇、十六酸乙酯、辛酸、癸酸乙酯、十二酸乙酯、辛酸乙酯、十四酸乙酯;对第二主成分贡献较大的是苯甲酸乙酯、丁二酸二乙酯、辛酸乙酯、壬醛。通过对发酵过程的分析,揭示了具体香气物质在桑葚果酒中的变化规律,获得了桑葚果酒香气物质的组成。

The changing trend of the aroma of mulberry wine during fermentation was analyzed by headspace solid phase micro-extraction combined with gas chromatography mass spectrometry(HS-SPME-GC-MS).The results indicated that 67 kinds of aroma substances were detected during fermentation,including 33 esters,4 alcohols,5 acids,8 aldehydes,2 phenols,6 terpenes and 9 other species.Many aroma-active substances contributed to the main aroma of mulberry wine.Esters were the important substances that contribute to the aroma of the mulberry wine,such as ethyl dodecanoate,ethyl tetradecanoate and ethyl cetate.In terms of alcohols,phenylethanol was the main component,which was the characteristic aroma during the fermentation of the mulberry wine.Among the acids,octanoic acid and decanoic acid were the main components,which could react with the ethanol generated during fermentation to produce ethyl octanoate and ethyl decanoate.In terms of the aldehydes,2-nonenaldehyde and 2,4-nondialdehyde only existed on Day 0,and other aldehydes decreased continuously during fermentation.Terpenes were also an important class of aroma substances in mulberry wine,such as longifolene,terpinene-4-ol and citronellol.But the content of terpenes decreased from 977.23μg/Lon Day 0 to 553.82μg/L at the end of fermentation.The principal component analysis revealed that the cumulative contribution rate of the two principal components reached 91.10%.The first class of principal components that made relatively large contributions were phenylethanol,ethyl hexadecate,octanoic acid,ethyl decanoate,ethyl dodecanoate,ethyl octanoate and ethyl tetradecanoate.The second class of principal components that made relatively large contributions were ethyl benzoate,diethyl succinate,ethyl octanoate and nonanal.Through the analysis of fermentation process,the changing trend of the specific aroma substances in mulberry wine was revealed,and the composition of aroma substances of the mulberry wine was obtained.