Changes of quality traits and phytochemical components of jujube fruit treated with preharvest GA3 and Parka during cold storage

Abstract

The study aimed to assess the effects of pre-harvest gibberellic acid (GA3) and Parka applications on fruit quality and bioactive components of jujube (Ziziphus jujuba Mill. cv. ‘Li’) fruit during the storage. Fruit were kept at 0±0.5 °C and 90±5% RH for 45 days. Parka and GA3 applications delayed weight losses and respiration rate in the cold storage. While the effect of the Parka application on the decrease in fruit firmness values depending on the storage time was not significant, it can be said that GA3 application was effective in maintaining the fruit firmness in the cold storage. The increase in soluble solids content (SSC) during cold storage was less with GA3 application. The decrease in titratable acidity with ripening in the cold storage was similar in the Parka and control applications. It can be said that GA3 application was effective in maintaining the titratable acidity during storage and this effect increased with the combination of Parka+GA3. The highest vitamin C at the end of the storage was recorded in fruit treated with Parka. Total phenolics, total flavonoids and antioxidant activity decreased in all applications during the storage. GA3 and Parka applications retarded the losses in total phenolics, total flavonoids and antioxidant activity in the storage. As a result, it can be said that the pre-harvest GA3 and Parka applications give positive results in maintaining the quality properties of jujube fruit in the cold storage.