基于GC-MS-O香气成分分析和多元统计分析的柚子品种鉴别

以浙江、江西和福建3个产地的5个柚子品种为试材,对我国不同地区和品种的柚子香气成分进行鉴定。通过固相微萃取技术(SPME)和气相色谱-质谱-嗅闻仪(GC-MS-O)相结合,对柚子的香气贡献组分进行鉴定。通过主成分分析(PCA)结合偏最小二乘判别法(PLS-DA)的多元统计分析方法进行品种间差异分析。根据GC-MS-O结果,5种柚子中挥发性组分种类构成丰富,不同品种的含量差异较大,主要包括萜烯类、醇类、醛类、酮类、酯类等。从柚子中共鉴定出香气贡献组分38种,其中柑橘味、松香味、香脂味、青草味、木香味等为主要呈现的香气属性。结合多元统计分析结果显示:PCA分析能较好地区分5种柚子品种,确定不同品种香气差异的贡献组分。PLS-DA方法实现了不同柚子品种间香气特征的差异分析,其中青草味、薄荷味、花香味和松香味可作为区分不同品种的主要特征风味。研究结果表明,基于香气组分的GC-MS-O分析结合多元统计分析可以鉴定国内各种类型的柚子。本研究结果为我国柚子品种鉴定,品质特性比较,柚子加工工艺探索以及产地溯源提供了理论基础。

Volatiles Identification of Pomelo Based on GC-MS-O and Multivariate Statistical Analysis

To identify the volatiles and aroma-active components of different pomelo varieties,five kinds of pomelo varieties from Zhejiang,Jiangxi and Fujian were tested.Solid phase microextraction(SPME)combining with gas chromatography-mass spectrometer-olfactometry(GC-MS-O)were used in this research.The chemometric methods,such as principal component analysis(PCA)and partial least squares discriminant analysis(PLS-DA),were used to distinguish different pomelo varieties and explain the differences.According to the analysis of volatiles by GC-MS-O,terpenes,alcohols,aldehyde,ketones,esters et al.were identified to be the main classes of volatile components.The content of these classes were different in five pomelo varieties.There are 38 aroma-active components identified in these varieties presenting the aroma properties of citrus,turpentine,balsamic,grass,wood et al.PCA can distinguish different varieties and determine the contribution of volatile components amongthem.PLS-DA has achieved to descriminate aroma characteristics among different varieties,and given the result that the flavor of grass,flower,mint and turpentine could be recognised as the main characteristics to distinguish different varieties.The results showed that the GC-MS-O coupling PCA and PLS-DA could be successfully used to identify and distinguish these five kinds of pomelo in China.This study provides the basis forthe comparison of variety characteristics,the processing of pomelo and the localization of origin.