不同方法提取油茶籽油品质比较及电子鼻分析

Quality comparison and electronic nose analysis of Camellia oleifera Abel seed oil extracted by different methods

采用气相色谱-质谱、化学法对浸出法、冷榨法和超临界流体CO2提取法所制油茶籽油的主要感官和理化指标进行了测定,并利用电子鼻技术对不同提取方法所制油茶籽油进行了鉴别。结果表明,3种提取方法所制油茶籽油在多项理化指标方面存在显著性差异。其中,超临界法所制油茶籽油的酸价、碘值与过氧化值均小于其他两种茶油,且其过氧化值与其他两种茶油相比具有显著性差异;3种茶油的中性色泽指标均具有显著性差异。其中,以冷榨法最低,浸出法最高;在脂肪酸组成和出油率方面,冷榨法所制的油茶籽油不饱和脂肪酸含量最高,浸出法出油率最高;而皂化值的结果表明,3种提取方法差异不显著。电子鼻技术的主成分分析和判别因子分析结果表明,累积方差贡献率分别为99.622%和99.999%,鉴别指数都为88,电子鼻技术能够对不同提取方法所制得的油茶籽油进行准确鉴别。

Gas chromatography-mass spectrometry and chemical methods were used to determine physical and chemical indicators and main sense of Camellia oleifera Abel seed oil extracted by cold pressing method,leaching method and supercritical CO2 method.The Camellia oleifera Abel seed oil extracted by three methods was analyzed and distinguished using electronic nose technology.The results showed that there were significant differences in many physical and chemical indicators of Camellia oleifera Abel seed oil extracted by different methods.The acid value,iodine value and peroxide value of Camellia oleifera Abel seed oil extracted by supercritical CO2 method were lower than those of two other Camellia oleifera Abel seed oil,and the peroxide value was significantly different from that of two other Camellia oleifera Abel seed oil.Furthermore,the neutral color indicators of three Camellia oleifera Abel seed oil had significant differences,among them,cold pressing method was the lowest and leaching method was the highest.In terms of fatty acid composition and production rate,the fatty acid composition of Camellia oleifera Abel seed oil extracted by cold pressing method was the highest,but the production rate by leaching method was the highest.The saponification values results indicated that the differences were not significant in three extraction methods.The principle component analysis of Camellia oleifera Abel seed oil analyzed and distinguished by electronic nose technology showed that cumulative variance contribution rate was 99.622%.The results of discriminant factor analysis showed that the cumulative contribution of the principal component was 99.999%,and the discriminant index was 88.The electronic nose technology can accurately identify Camellia oleifera Abel seed oil extracted by different processing methods.