Abstract:
【Objective】 To investigate the effects of different preservation and packaging methods on the sprout suppression effect and storage quality of sweet potato, to develop a safe and environmentally friendly post-harvest preservation technology, and to provide new ideas for sweet potato post-harvest sprout suppression and storage and transportation preservation. 【Method】 Using Watermelon Red sweet potato as test material, under room temperature(16-20 ℃) storage conditions, polyethylene film freshness bag(CK), polyvinyl alcohol(PVA) freshness bag and MP20 spontaneous airconditioning packaging bag were used to package sweet potato after healing treatment, and 3 fruits of uniform size were packed into each bag, and the samples were taken on the 0
th, 10
th, 20
th, 30
th and 40
th d of storage, respectively. The changes in postharvest quality-related indexes such as germination rate, hardness, weight loss, gas composition, vitamin C(Vc), starch, reducing sugar, sucrose, polyphenol oxidase(PPO) and peroxidase(POD) were determined. 【Result】 After 10 d of storage at room temperature, the sweet potato in CK had obvious buds on the roots, with a germination rate of 77%, while the sweet potato treated with PVA packaging still had no buds after 40 d of storage, with a germination rate of 0. Compared with CK, the PVA packaging treatment could obviously inhibit the growth of sweet potato buds, maintain higher hardness, and maintain a more stable O
2 and CO
2 contents inside the bag, providing a low O
2 and high CO
2 gas environment was conducive to the storage and preservation of sweet potato. Until the 40
th d of storage, the sweet potato starch contents of PVA and MP20 packaging treatment were 11.67 and 10.25 mg/g, and the Vc contents were 144.53 and 125.28 mg/g, which was extremely significantly higher than that of CK(
P<0.01, the same below); PVA and MP20 packaging treatments could maintain the higher content of reducing sugar and sucrose in post-harvest sweet potato. On the 40
th d, the reducing sugar and sucrose contents of PVA packaging treatment were 5864.52 μg/g and 37.82 mg/g, respectively, which were 20.61% and 15.62% higher than that of CK, respectively. PVA packaging treatment also significantly inhibited the increase of PPO and POD activities, and by the end of the storage period, the activities of PPO and POD were reduced extremely significant compared with that of CK. 【Conclusion】 PVA packaging treatment can effectively inhibit the sprouting of sweet potato buds. MP20 spontaneous air-conditioning packaging and PVA packaging treatment can delay the decline in nutrient content and hardness of sweet potato, which is conducive to maintaining nutrients and commodity value, improve the storage resistance of sweet potato, and the preservation of freshness is better with PVA bags.