Optimization of the Extraction Technology and the Physiochemical Properties of Theabrownin from Liupao Tea

The optimum extraction technology of theabrownine from Liupao tea was studied, and the physiochemical properties of theabrownine were analyzed. The effects of material-liquid ratio, extraction temperature, extraction time on yield of theabrownine were investigated by single factor experiment. Response surface methodology (RSM) was used to investigate the optimum extraction conditions of Liupao tea's theabrownine. Then the physiochemical properties of the obtained theabrownine were analysized. Results showed that, the yield of theabrownine was 10.33%±0.04% under the optimum extracting conditions:material-liquid ratio 1:37 g/mL, extraction temperature 96℃, extraction time 86 min. The theabrownine contains polysaccharides 25.16%±0.11%, proteins 15.45%±0.06%, total acid groups (5.5±0.02) mmol/g, carboxy groups (1.34±0.05) mmol/g, phenolic hydroxyl groups (4.16±0.06) mmol/g. Response surface methodology (RSM) was feasible to optimize the theabrownin's extraction conditions, that theabrownine was mainly composed of phenolic compounds and carboxylic compounds, accompanied with proteins and polysaccharides.