Automatic periodical SO_2 fumigation improves the storage quality of tender ginger

摘要

Rhizome rot and quality deterioration of tender ginger after harvest were the restrictingfactors of tender ginger storage quality. In this research, cold storage withSO_2 fumigation function was designed and the effects of 0.2, 0.5, and 1.0 ml L~(−1) SO_2fumigation every 15 d on the storage quality of tender ginger was investigated. Theimproved cold storage and supporting equipment can automatically fill and removeSO_2 gas into the storage room, and keep the humidity stable at 92%–95%duringstorage. Experimental results showed that automatic periodical SO_2 fumigation oftender ginger with 0.5 ml L~(−1) SO_2 every 15 d can effectively maintain firmness (～56%),retard weight loss (～22%), reduce decay rate (～20%), and inhibit the accumulation ofmalondialdehyde (MDA) content (～26%). Meanwhile, the 0.5 ml L~(−1) SO_2 treatmentenhanced the disease resistance of tender ginger by enhancing phenylalanine ammonialyase (PAL) activity (～8%) and inhibiting polyphenol oxidase (PPO) activity (～25%),and the integrity of tissue structure was also well maintained. More importantly, theSO_2 residue in the tender ginger treated with the 0.5 ml L~(−1) SO_2 completely met theFDA food safety standard on the 50 d. Therefore, the combination of cold storagestructure innovation and 0.5 ml L~(−1) SO_2 periodical fumigation is more effective atimproving the storage quality of tender ginger.