Nutrient composition and quality traits of dried jujube fruits in seven producing areas based on metabolomics analysis

Chinese jujube is a widely cultivated fruit of the Rhamnaceae family. However, there are few reports on the comprehensive evaluation of jujube fruit quality in the main jujube producing areas. Liquid chromatography tandem-mass spectrometry (LC-MS/MS), principal component analysis (PCA), cluster analysis, and ranking score were used to comprehensively evaluate the metabolic traits and quality of 20 dried jujube varieties in the seven main producing areas in China. A total of 29 categories of 463 metabolites were identified and detected; among them, alkaloids, amino acids, flavonoids, and lipids are the main nutrients in dried jujube fruits. An analysis of the content of metabolites in dried jujube fruits from seven producing areas showed that the difference in the fruit quality traits between the producing areas is significant, exhibiting the regional characteristics of the eastern and western regions in North China. In addition, jujube varieties HN-L-L (72 points), XJ-H-Hm (59 points), and XJ-H-Hp (59 points) with the highest scores are rich in nutrients and can be used as raw materials in the development of functional foods.