Changes in quality properties and volatile compounds of different cultivars of green plum (Prunus mume Sieb. et Zucc.) during ripening

The variation in physicochemical characteristics, bioactive components, antioxidant capacity, and volatile compounds of different cultivars of green plum during the ripening was investigated. The alterations in bioactive components and volatile compounds of six cultivars green plum ('Baifen', 'Nangao', 'D-1', 'Yingsu', 'Qingzhu', and 'Changnong') during the ripening were determined by HPLC and GC-MS, respectively. The levels of total phenolics, ascorbic acid, organic acid, phenolic acid, and antioxidant capacity of green plum samples showed a first upward and then downward tendency during the ripening process. The cultivar had a great impact on the phytochemical compounds contents of green plum during ripening, and the 'Qingzhu' green plum (QZ) showed higher bioactive compounds concentrations and antioxidant capacity in comparison to the other cultivar green plums. Moreover, the volatile compounds of green plum were also affected by maturity stage and cultivar. The green plums ('Baifen', 'Nangao', 'D-1' and 'Yingsu') in the ripening stage presented the highest contents of esters and alcohols, while the main aroma substances of QZ and 'Changnong' green plum were aldehydes and terpenes, which were responsible for a strong fruit flavor. The results of this study provided valuable information for the processing and utilization of green plum.