[Study on enzyme extraction technology of total flavonoids from Cryptotaenia japonica].

OBJECTIVE: To study the optimum enzyme extraction process of total flavonoids from Cryptotaenia japonica. METHODS: The process was optimized by single factor experiments and orthogonal, the yield of total flavonoids was used as index. RESULTS: The optimum extraction technology was as follows: enzyme dosage: 1U/mL, pH value: 6.0, enzymatic hydrolysis temperature: 60%, enzymatic hydrolysis time: 1 h, the rate of material to liquid: 1 : 30, extraction temperature: 70 degrees C, extraction time: 1 h, the average extraction rate of total flavonoids from Cryptotaenia japonica was 4.76%. CONCLUSION: The method is an effective way to extract total flavonoids from Cryptotaenia japonica with high extract rate.

Study on lipolysis-oxidation and volatile flavour compounds of dry-cured goose with different curing salt content during production.

The effect of dry-curing salt content (4% low salt (LS), 8% high salt (HS)) on lipolysis, lipid oxidation and volatile compounds in dry-cured goose was investigated in our study. The activities of acid lipase and neutral lipase increased during dry-curing, while phospholipase reached its maximum at the end of marinating. Lipoxygenase (LOX) and thiobarbituric acid reactive substances (TBARS) values increased during dry-curing and marinating then decreased during dry-ripening. Total free fatty acids (TFFA) increased at dry-curing and dry-ripening points and decreased during marinating. Total peak area of lipids derived volatile compounds (TPALDVC) and total peak area increased during entire stages. Compared to LS, HS group has higher lipolytic and LOX activities, TBARS, TFFA, unsaturated fatty acids and TPALDVC. The higher TPALDVC in HS could be attributed to higher lipid hydrolysis and oxidation during processing.