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

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.