基于GC-IMS技术分析五种市售不同工艺油莎豆油理化品质与风味差异

Analysis of Physicochemical Quality and Flavor Differences of Five Commercially Available Tiger Nut Oils with Different Processes Based on GC-IMS Technique

为研究市售不同工艺油莎豆油理化品质与风味的差异性,采用气相离子迁移谱(Gas Chromatography-Ion Mobility Spectroscopy,GC-IMS)技术结合主成分分析法对比不同工艺(物理压榨、热榨、亚临界萃取、高压冷榨和冷榨工艺)油莎豆油挥发性化合物之间的差异性。GC-IMS结果显示,不同工艺油莎豆油中共鉴定出76种挥发性化合物,其中包括酯类12种、醇类16种、醛类29种、酮类9种、酸类5种、呋喃类3种、吡嗪类1种、硫类1种。热榨组醛类、酯类和呋喃类物质相对含量较高(53.54%,13.06%,5.41%)。不同工艺油莎豆油风味差异性主要来源于四种关键风味物质:1-烯-3-辛醇、壬醛、(E)-2-辛烯醛和己醛。主成分分析(Principal Component Analysis,PCA)结果表明PC1和PC2分别为48.7%和30.1%,累计差异贡献率为78.8%,不同工艺油莎豆油风味物质差异显著,能够对不同工艺油莎豆油良好区分。Pearson相关性分析结果表明不同工艺油莎豆油b*值与酸价、过氧化值、p-丙二醛值和1-烯-3-辛醇之间呈显著正相关(0.57<r<0.88,P<0.05)。本研究结对市售油莎豆油生产加工、理论研究和质量检测等领域具有一定的参考价值。

In order to evaluate the differences in physicochemical quality and flavor of commercially edible tiger nut oil,gas chromatography-ion mobility spectroscopy(GC-IMS)combined with principal component analysis was used to compare the volatile compounds in tiger nut oil from different extraction methods(physical pressing,hot pressing,subcritical extraction,high-pressure cold pressing and cold pressing).The GC-IMS results showed that 76 volatile compounds including 12 esters,16 alcohols,29 aldehydes,9 ketones,5 acids,3 furans,1 pyrazine and 1 sulfur compound were identified in the oil from different extraction methods.The relative content of aldehydes,esters and furans(53.54%,13.06%,5.41%)in the hot-pressing group were higher than others.The flavor differences of tiger nut oil from different processes were mainly derived from four key flavor substances as 1-octen-3-ol,nonanal,(E)-2-octenal and hexanal.The results of principal component analysis(PCA)showed that PC1 and PC2 were 48.7%and 30.1%,respectively,with a cumulative difference contribution of 78.8%,and the differences in volatile compounds between different processes were significant,which could be well distinguished by different extraction methods.The results of pearson correlation analysis showed that there was a significant positive correlation between b*value and acid value,peroxide value,p-malondialdehyde value and 1-octen-3-ol(0.57<r<0.88,P<0.05).The research could provide some reference value for the production and processing,theoretical research and quality inspection of commercial tiger nut oil.