电子鼻结合顶空SPME-GC-MS联用技术分析贵州不同品种辣椒发酵后挥发性成分

以贵州5种不同辣椒品种为研究对象,采用电子鼻技术,结合顶空固相微萃取-气相色谱-质谱(solid phase microextraction-gas chromatography-mass,SPME-GC-MS)联用技术,对其发酵后挥发性成分进行分析。结果表明,电子鼻分析结果能够很好地区分不同辣椒品种发酵后的风味;采用主成分分析(principal component analysis,PCA)以及线性判别分析(linear discriminant analysis,LDA)可知,PCA和LDA主成分贡献率总和分别为99.93%、99.19%,均大于95%,说明传感器识别效应和样品间的风味区分度较好。SPME-GC-MS分析结果表明,5种样品共检出124种不同的挥发性风味物质。其中黄平线椒占97种,以酯类物质相对含量最高,为36.82%;施秉线椒和大方皱椒分别占88种和94种,且均以醇类物质相对含量最高,分别为31.88%、28.99%;百宜平面椒和花溪党武辣椒分别占89种和71种,均以烃类物质相对含量最高,分别为26.75%、35.08%。此结果与电子鼻PCA和LDA结果相一致。因此,通过SPME-GC-MS和电子鼻分析结果可知,电子鼻能够很好地区分贵州名优产地不同辣椒品种发酵后的风味。

Analysis of the Volatile Components of Fermented Hot Pepper from Different Varieties Grown in Guizhou by Electronic Nose Combined with SPME-GC-MS

In this research, electronic nose (E-nose) and solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) were used to evaluate and compare the volatile components of fermented hot pepper from different varieties grown in Guizhou. The results showed that the E-nose could distinguish among five different varieties of fermented hot pepper. In principal component analysis (PCA) and linear discriminant analysis (LDA), the cumulative contribution of the first 2 principal components accounted for greater than 95% (99.93% and 99.19% , respectively) of total variance, suggesting that the E-nose sensors had good recognition performance and discrimination between samples on the basis of their flavor characteristics was excellent with clear distinctions. A total of 124 volatile compounds were identified, 97 of which were found in fermented Huangping line pepper, with esters being the most abundant constituents (36.82%); 88 and 94 of which in fermented Shibing line pepper and Dafang wrinkle pepper, respectively, the predominant ones being alcohols (31.88% and 28.99%, respectively); and 89 and 71 of which in fermented Baiyi plane pepper and Huaxi Dangwu pepper, respectively, hydrocarbons being the major ones (31.88% and 28.99%, respectively). These results were consistent with PCA and LDA. Therefore, the electronic nose is useful for clear discrimination of fermented pepper from different varieties grown in Guizhou.