成熟度指数对不同品种橄榄油脂肪酸、 酚类化合物及风味属性的影响

以甘肃省陇南市油橄榄研究所种质资源基因库的‘城固32号’和‘莱星’油橄榄果为原料提取橄榄油，运用GC-MS、HPLC和E-Nose对不同品种与不同成熟度指数的橄榄油脂肪酸、酚类化合物及风味属性进行检测分析，以探究成熟度指数与不同品种橄榄油品质的关系。结果表明：随着成熟度指数的增大，‘城固32号’橄榄油中的硬脂酸、油酸、亚麻酸、饱和脂肪酸（SFA）含量及单不饱和脂肪酸/多不饱和脂肪酸（MUFA/PUFA）和油酸/亚油酸值呈下降趋势，亚油酸和不饱和脂肪酸（UFA）含量呈上升趋势，‘莱星’橄榄油中油酸和UFA含量及MUFA/PUFA和油酸/亚油酸值呈上升趋势，而亚油酸、亚麻酸和SFA含量呈下降趋势；油酸/亚油酸和MUFA/PUFA值在2个品种间存在差异，可作为鉴别‘城固32号’和‘莱星’橄榄油的依据；2个品种橄榄油中酪醇和总酚含量总体呈下降趋势，香草酸和木犀草素含量总体呈上升趋势，而羟基酪醇含量在‘城固32号’中总体逐渐减少，在‘莱星’中总体逐渐增加，木犀草苷含量在2个品种中保持稳定；风味物质的E-Nose信号响应值在2个品种中均显著减小。利用橄榄油中脂肪酸和酚类化合物的组成与含量以及风味属性的信号响应值差异结合主成分（PCA）分析可有效鉴别和区分不同成熟度指数的‘城固32号’和‘莱星’橄榄油。

Effect of maturity index on fatty acids, phenolic compounds and flavor attributes of olive oil from different varieties

The olive fruits of Chenggu 32 and Leccino which were taken from the germplasm resource gene bank of Olive Research Institute of Longnan, Gansu Province were used as raw materials to extract olive oil. The fatty acids, phenolic compounds and flavor attributes of olive oil with different varieties and different maturity indexes were detected and analyzed by GC-MS, HPLC and E-nose technology to explore the relationship between qualities of different varieties of olive oil and maturity index. The results showed that with the increase of maturity index, the contents of stearic acid, oleic acid, linolenic acid and saturated fatty acid (SFA), and ratios of monounsaturated fatty acids to polyunsaturated fatty acids (MUFA/PUFA) and oleic acid to linoleic acid in olive oil of Chenggu 32 showed a decreasing trend, while the contents of linoleic acid and unsaturated fatty acid (UFA) showed an increasing trend. However, not only the contents of oleic acid and UFA, but also the ratios of MUFA to PUFA and oleic acid to linoleic acid were on the rise in olive oil of Leccino, while the contents of linoleic acid, linolenic acid and SFA were on the decline. The difference in the ratios of oleic acid to linoleic acid and MUFA to PUFA between the olive oils of Chenggu 32 and Leccino could be used as the basis for the identification of them. In addition, with the increase of maturity index, the contents of tyrosol and total phenol in olive oil of the two varieties showed an overall decreasing trend, but the contents of vanillic acid and luteolin showed an overall increasing trend. The content of hydroxytyrosol in Chenggu 32 gradually decreased overall while that in Leccino gradually increased overall. The content of cynaroside remained stable in olive oil of the two cultivars. The E-nose response signal values of flavor substances were significantly reduced in olive oil of both cultivars. The composition and content of fatty acids and phenolic compounds in olive oil as well as the difference of flavor attribute signal response values combined with principal component analysis (PCA) could be used to effectively identify and distinguish Chenggu 32 and Leccino olive oil with different maturity indexes.