基于顶空固相微萃取-气相色谱-质谱联用法、电子鼻和电子舌技术分析绿茶饮料的风味物质

Analysis of flavor substances in green tea beverages detected by HS-SPME/GC-MS coupled with electronic nose and electronic tongue technology

[目的]本文旨在分析绿茶饮料中的特征挥发性和非挥发性化合物,为绿茶饮料风味质量评价提供科学参考。[方法]利用顶空固相微萃取-气相色谱-质谱联用仪(headspace solid phase micro-extraction gas chromatography mass spectrometry,HS-SPME/GC-MS)和电子鼻技术,对12种绿茶饮料的挥发性风味物质进行测定,并结合电子舌和全自动氨基酸分析仪对绿茶饮料中的非挥发性成分进行比较。[结果]利用HS-SPME/GC-MS在12种绿茶饮料中共检测出135种香气物质,其中酯类40种,醇类21种,醛酮类27种,萜烯类31种,烃类8种,酚类4种,酸类1种,其他物质3种。共有的挥发性香气组分是柠檬烯、α-松油醇和芳樟醇,根据气味活度值(odour activity value,OAV)确定芳樟醇是绿茶饮料的特征香气物质,挥发性物质种类和含量赋予绿茶饮料独特的风味。主成分分析(principal component analysis,PCA)结果表明电子鼻和电子舌可以区分12种绿茶饮料,第一主成分(PC1)与第二主成分(PC2)的贡献率之和分别达91.08%和92.58%。茶氨酸是绿茶饮料中含量最高的游离氨基酸,茶氨酸含量与绿茶饮料整体滋味呈显著正相关(P<0.05)。[结论]不同种类绿茶饮料的气味和滋味特征存在差异,通过HS-SPME/GC-MS、电子鼻、电子舌和氨基酸分析技术相结合的手段,可以较好地分析12种绿茶饮料中的风味物质。

[Objectives]The aim of this article was to analyze the volatile and non-volatile compounds of green tea beverages,providing scientific reference for the flavor quality evaluation of green tea beverages.[Methods]Headspace solid phase micro-extraction gas chromatography mass spectrometry(HS-SPME/GC-MS)and electronic nose technology(E-nose)were used to study the volatile flavor substances of 12 green tea beverages.The differences in taste and amino acid content of green tea beverages were analyzed using electronic tongue(E-tongue)and automatic amino acid analyzer.[Results]A total of 135 aroma compounds,including 40 esters,21 alcohols,27 aldehydes and ketones,31 terpenes,8 hydrocarbons,4 phenols,1 acid,and 3 other substances were identified via HS-SPME/GC-MS in the 12 green tea beverages samples.Limonene,α-terpineol and linalool were found in all samples,and the characteristic aroma compound of green tea beverages was linalool,which was confirmed by odor activity value(OAV).The different types and contents of these volatile substances gave the green tea beverages a unique flavor.E-nose and E-tongue technology was found to be a good classifying tool for 12 green tea beverages,and the cumulative contribution rates of PC1 and PC2 were 91.08%and 92.58%,respectively.The highest content of amino acids in green tea beverages was theanine,and the concentration of theanine was significantly positively correlated with the overall taste(P<0.05).[Conclusions]Different odor and taste characteristics were observed in green tea beverage.The characterization of flavor frame in 12 green tea beverages was well analyzed and detected by HS-SPME-GC-MS coupled with electronic nose,electronic tongue,and amino acid analysis.