Effect of cold water and cold electrolyzed functional water treatments on the postharvest quality of cold stored jujube fruit ( Ziziphus jujuba Mill. “Hupingzao”)

Abstract

This study evaluated the effect of cold electrolyzed functional water (CEFW) treatment on the quality of cold-stored Hupingzao jujube fruit. In the study, the fruit firmness, total soluble solids (TSS), titratable acid (TA), TSS/TA ratio, color development, weight loss, respiration rate, vitamin C content, malondialdehyde (MDA) content were evaluated. In addition to this, the polyphenoloxidase (PPO), superoxide dismutase (SOD), and peroxidase (POD) activities were assessed. The results indicated that CEFW treatment inhibited the decline in firmness, weight loss, vitamin C content, and fruit brightness. On the 100th day, CEFW treatment reduced the fruit TSS/TA to 119.74, respiration rate to 32.91 CO2 mg kg−1 h−1, peel color reddening index a*/b* to 0.53, and PPO activity to 3.97 U min−1 g−1. The MDA content of CEFW-treated fruit was 1.31 μmol g−1, which was significantly lower than the control group; the activity of SOD and POD in CEFW-treated fruit was 35.49 U g−1 and 2.31 U min−1 g−1, respectively, which were significantly higher than the control group. In conclusion, cold water and CEFW treatments could delay the senescence of postharvest jujube fruit and maintain the fruit quality during cold storage, and CEFW treatment had better effect. Novelty impact statement The quality of Hupingzao jujube was declined during cold storage. The reddening of the jujube fruit peel was alleviated after cold water and cold electrolyzed functional water treatments, and the fruit quality was maintained. And the cold electrolyzed functional water treatment had better effect.