Effects of Refrigerating Time on Nutrient Quality of Two Chemical-Ecotypes of Purple Perilla

In order to determine suitable preservation period, leaves of purple and common perilla were used as materials to study nutrient quality of two chemical-ecotypes of purple perilla while refrigerating at 4℃ for 0, 1, 3, 5, 7 and 14 days, respectively. The results showed that content of crude protein and crude fiber in leaves of purple perilla reached 25.8 g·hg^-1 and 8.0 g·hg^-1, respectively and were significantly higher than that of common perilla while content of crude fat in leaves of purple perilla reached 16.2 g·hg^-1 and was significantly lower than that of common perilla. At 4℃ there were significant differences of nutrient quality between two ecotypes. Content of Soluble sugar and soluble protein showed trends of firstly decline and then rising with prolonged refrigerating time. Content of total phenols and flavonoids showed little changes with prolonged refrigerating time. But content of total phenols and flavonoids in purple perilla were significantly higher than that of common perilla. Content of free amino acids showed rising trend at 4℃ for 3 days. Moreover, content of free amino acids in leaves of purple perilla was higher than that of common perilla. After 3 days at 4℃ content of free amino acids in leaves of purple perilla declined markedly and was lower than that of common perilla; Vc content in leaves of purple perilla declined sharply with prolonged refrigerating time and was higher than that of common perilla. while 7 days at 4℃ content of soluble sugar in leaves of common perilla decreased than fresh leaves by 42% while content of soluble sugar in leaves of purple perilla increased than fresh leaves by 33%; content of soluble protein in leaves of common perilla decreased than fresh leaves by 52% while content of soluble protein in leaves of purple perilla increased than fresh leaves by 76%; content of free amino acids in leaves of common perilla increased than fresh leaves by 191% while content of free amino acids in leaves of purple perilla decreased than fresh leaves by 10%; content of total phenols and flavonoids show no evidently changes. In general, leaves of purple perilla have richer nutrition than that of common perilla and stronger tolerance to refrigerating storage, but at 4℃ it should be stored below 7 days.