Evaluation of Postharvest Storability of Ponkan Mandarins at Different Storage Temperatures Based on Principal Component Analysis

To reduce postharvest losses of Ponkan mandarins caused by outdated storage facilities and preservation technology, we evaluated the preservation effect of different storage temperatures on Ponkan mandarins (5 {+/-}1, 10 {+/-} 1, 15 {+/-} 1, and 20 {+/-}1 {degrees}C), and obtained a comprehensive score using principal component analysis (PCA) to determine its suitable storage temperature. The results indicate that, relative to the other three storage temperatures, storage at 10 {degrees}C significantly maintains high total soluble solid content, titratable acid, and vitamin C contents; the accumulation of malondialdehyde (MDA) and hydrogen peroxide (H2O2) content decreased and changes in the relative conductivity (REC) were suppressed; and high activities of superoxide-dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX), as well as high contents of total phenol and total flavonoid were maintained. The PCA and clustering heat map results show that that the comprehensive score was the highest when stored at 10 {degrees}C. The data indicate that the suitable storage temperature of Ponkan mandarins at 10 {degrees}C significantly decreased MDA accumulation and reactive oxygen species metabolism, maintains high antioxidant capacity, maintains good fruit quality and achieves good storage and preservation effect, which is the appropriate storage temperature for Ponkan mandarins.