草莓汁中糖酸组成分析及其在掺假鉴别中的应用

Compostion Analysis of Soluble Sugars and Organic Acids in Strawberry Juice and Its Application for Authentication

为了解草莓汁的糖酸组成特点并探索其在掺假鉴别中的应用,采用高效液相色谱法对10个品种草莓果汁中可溶性糖、有机酸组成与含量进行分析,结合化学计量学方法探索其在草莓汁掺假鉴别中的应用。结果表明,草莓汁中可溶性糖主要由蔗糖、葡萄糖和果糖组成,有机酸主要是柠檬酸和苹果酸。不同品种草莓果汁中各种可溶性糖和有机酸的含量存在较大差异,但葡萄糖与果糖的比值受品种影响较小,柠檬酸占检测到总有机酸含量的62.39%~82.73%。通过分析草莓原汁及其掺假样品中可溶性糖和有机酸组成,结合主成分分析和线性辨别分析等模式识别方法,可以实现对草莓果汁与掺加梨汁、苹果汁、杏汁和桃汁等掺假样品的区分,而且掺假量越大,区分效果越好。草莓果汁可溶性糖和有机酸组成特征结合化学计量学分析能够对掺假草莓果汁进行较好地区分,可用于草莓果汁掺假鉴定和质量控制。

In order to understand the composition characteristics of sugar and acid in strawberry juice and explore its application in adulteration identification,the composition and content of soluble sugar and organic acid in 10 kinds of strawberry juice,the application of stoichiometry in the identification of strawberry juice adulteration was studied. Results showed that the soluble sugars in strawberry juices mainly consisted of sucrose,glucose,and fructose,while citric acid and malic acid were the main organic acids in strawberry juices. There were great differences among the contents of soluble sugars and organic acids in strawberry juices of different varieties,while the ratios of glucose to fructose showed little differences among varieties. Furthermore,citric acid was the predominant organic acid in strawberry juices of all varieties,accounting for 62.39%~82.73% of the total content of identified organic acids. By determining the compositions of soluble sugars and organic acids coupled with principal component analysis and linear discriminant analysis,strawberry juices could be discriminated from their adulterates with pear juice,apple juice,apricot juice,and peach juice. The composition characteristics of soluble sugar and organic acid in strawberry juice,combined with stoichiometric analysis,can be used for adulterated strawberry juice identification and quality control.