Abstract:To obtain the optimum ultra high pressure-assisted extraction technology of tea-polyphenols from low value tea. On the basis of single-factor test, the mathematical regression model is established about the dependent variable(extraction yield of tea-polyphenols ) and independent variables (alcohol concentration, time of maintain pressure and extraction pressure) through Box-Benhnken center composite design and response surface methodology. The results indicated that the optimal extraction conditions were alcohol concentration of 60%, processing time of 1.5 min, extraction pressure of 300 MPa. Under these conditions, the predictive maximum yield of tea-polyphenols from low value tea was 31.07%, the validation value was 30.87%. The relative error between them was 2.59% .The standardized regression equation was Y1=776.3561-1.3356X1+123.093X2+163.7406X3-274.2023X1X1-145.2251X2X2.
