Analysis of Quality Characteristics of Winter Jujube from Different Regions Using Principal Component Analysis and Cluster Analysis

In this study, 18 quality indexes of winter jujube collected from five major production areas were determined. Quality evaluation and determination of the key indexes were carried out using multiple comparison, correlation analysis, principal component analysis, cluster analysis and Fisher discriminant analysis. Then, the feasibility of tracing the geographical origin of winter jujube was discussed according to the key quality indexes. The comprehensive analysis of principal component scores indicated that Xinjiang’s Hotan and Shandong’s Zhanhua were superior production areas. Further cluster analysis showed that the 18 quality indexes of winter jujube could be represented by eight key indexes, including soluble solid content, potassium, manganese, individual fruit mass, hardness, ethanol, color and water content. Fisher discriminant analysis showed that the eight key indexes could be used to trace the geographical origin of winter jujube with an overall discrimination accuracy of 100.0%, and a discrimination accuracy for cross-validation of 97.2%. This study provides a theoretical basis for the quality evaluation and key quality index determination of winter jujube from different production areas, which will be of great significance for the geographical origin traceability and production of winter jujube.