Effects of pretreatments and storage temperatureon the quality of lotus leaves

Abstract

This study aimed to investigate the effects of pretreatments blanching, roasting, drying, and storage temperatures (25℃, 4℃ and -10℃) on their quality of lotus leaves. As a result, the lotus leaves retained a good appearance when stored at 25℃ for 5 days, 4℃ for 30 days, and -10℃ for 90 days, regardless of the pretreatment used. At the same storage temperatures, pH, soluble solids, total acid content, polyphenols, and microorganisms were significantly different among the pretreatments (p<0.05). Soluble solids, pH, and total acid contents were not significantly different for the same pretreatments at different storage temperatures. However, the polyphenol, oxalic acid, and tartaric acid contents of lotus leaves were significantly different after drying and blanching treatments. In particular, it was shown that polyphenol content of the lotus leaf was affected by both pretreatment and storage temperature. In conclusion, the lotus leaves appeared in good condition until 5 days at 25℃, 30 days at 4℃, and 90 days at -10℃, regardless of the pretreatment while influenced by storage temperature.