猕猴桃品质指标差异分析及GC-IMS分析果汁中挥发性物质

Different Varieties of Kiwifruit:Analysis of Differences in Quality Indexes and Volatile Components in Juice by Gas Chromatography-Ion Mobility Spectrometry

以金艳、红阳、东红及万州红心4种猕猴桃为原料,比较样品间感官差异(外观、内部横切面形态)、品质差异(出汁率、可溶性固形物、总糖、pH值、可滴定酸、VC、总酚、花色苷、黄酮、单宁),结合主成分分析与聚类分析法对样品分析,同时采用气相色谱-离子迁移谱(gas chromatography-ion mobility spectrometry,GCIMS)技术对不同品种猕猴桃果汁中挥发性成分进行分析。结果表明,4个品种出汁率、总酸等含量差异不明显,万州红心猕猴桃品种中总糖、VC、总酚、黄酮及花色苷含量较其他3个品种高,金艳品种中单宁含量较高,主成分分析和聚类分析结果较一致,金艳聚为一类,红阳、东红及万州红心聚为一类;采用GC-IMS技术在4种猕猴桃果汁中共检测出55种挥发性物质,不同样品之间挥发性物质差异较大,按照挥发性成分进行主成分分析与聚类分析,对样品进行分类,结果与按照品质指标分类结果一致。

This study aimed to compare the differences in the sensory(appearance and cross-sectional morphology)and physicochemical characteristics(juice yield,total soluble solids(TSS),total sugars,pH,titratable acids,vitamin C,total phenolics,anthocyanins,flavonoids and tannins)of four different varieties of kiwifruit(Hongyang,Jinyan,Wanzhou Hongxin and Donghong).The fruit quality data were analyzed by principal component analysis(PCA)and cluster analysis(CA),and the volatile aroma compounds of juice samples were analyzed by gas chromatography-ion mobility spectrometry(GC-IMS).The results showed that there was no significant difference in juice yield or total acid content among varieties,and the contents of total sugars,vitamin C,total phenolics,flavonoids,anthocyanins in Wanzhou Hongxin were higher than those in the other varieties,while tannin content was higher in Jinyan than in the other varieties.The results of PCA and CA consistently showed that Jinyan was classified into one group,whereas Hongyang,Wanzhou Hongxin and Donghong were classified into another group.A total of 55 volatile components were detected across four juice samples,and there were significant differences in volatile compounds among these samples.The results of classification by PCA and CA based on volatile components were consistent with those based on quality index.