基于气相色谱-离子迁移谱技术的隔年东北酸菜风味鉴别研究

Flavor identification of over-year Dongbei Suancai based on GC-IMS

为探索一种隔年东北酸菜的快速鉴别方法,该研究采用气相色谱-离子迁移谱(gas chromatography-ion mobility spectroscopy,GC-IMS)技术分析比较了隔年酸菜和当年酸菜的挥发性特异气味成分。结果表明,2组酸菜中共鉴定出22种挥发性风味化合物,包括酯类、酮类、醇类、酸类等。指纹图谱显示2组样品风味物质的种类和含量均存在明显差异,主要表现为在当年酸菜中挥发性风味物质的种类更为丰富,包括二甲基二硫化物、乙酸乙酯、丁酸乙酯、3-甲基丁酸乙酯、丁酸甲酯、2,3-丁二酮、丙酮、丁酸、乙醇等;而在隔年酸菜中上述风味物大量减少或消失,仅乙酸乙酯和乙醇的信号强度有所增加,并生成了大量的乙酸丙酯、正丙醇、丙酸乙酯、丁酮等特征风味化合物。通过风味物质的主成分分析,当年与隔年酸菜样品分别占据了2个相对独立的空间,并得到了准确区分。因此,应用GC-IMS结合主成分分析的方法可实现隔年酸菜的快速鉴别。

To explore a rapid identification method of over-year Dongbei Suancai,gas chromatography-ion migration spectrometry(GC-IMS)was used to analyze and compare the volatile flavor compounds in over-year(stored over summer,more than 12 months)and current-year(fermented and consumed within 6 months)Dongbei Suanbei.Results showed that a total of 22 representative volatile flavor compounds,including esters,ketones,alcohols and acids,were identified in the two groups.Fingerprint indicated that there were significant differences in the types and contents of flavor compounds between the two groups,manifesting as the kinds of volatile flavor compounds were relatively more in current-year Dongbei Suanbei,containing dimethyl disulfide,ethyl butanoate,ethyl 3-methyl butanoate,methyl butanoate,butanoic acid,2,3-butanedione,acetone,ethyl acetate,ethanol,etc,but those were substantially reduced or nearly disappeared in over-year Dongbei Suanbei,only the signal of ethyl acetate and ethanol were enhanced,and a large number of other characteristic flavor compounds such as n-propyl acetate,n-propanol,ethyl propanoate and butanone were generated.Through the principal component analysis of flavor substances,over-year and current-year Dongbei Suanbei occupied two relatively independent spaces and were distinguished accurately.Therefore,GC-IMS combined with principal component analysis could be used to quickly identify over-year Dongbei Suanbei.