Quantification of Phenolic Compounds in Different Tissues and Juice of Satsuma Mandarin Fruit by High-Performance Liquid Chromatography

This study investigates the distribution and quantification of phenolic compounds in different tissues (juice, pulp, and peel) of six Satsuma mandarin (Citrus unshiu) varieties cultivated in Croatia. Narirutin and hesperidin were the dominant flavonoids in mandarin juice and pulp, with the highest concentrations observed in the “Okitsu” variety. Peel samples exhibited a higher flavonoid content, particularly hesperidin and polymethoxylated flavones, such as nobiletin and tangeretin. Extractable and bound phenolic acids, including ferulic, caffeic, and p-coumaric acids, were quantified. The “Okitsu” variety showed the highest levels of most phenolic acids. The optimized high-performance liquid chromatography method demonstrated high precision and sensitivity, enabling efficient quantification of 18 phenolic compounds. This study provides valuable insights into the phenolic composition of Satsuma mandarins, contributing to citrus quality assessment, dietary applications, and sustainable utilization of citrus waste.