Résumé
OBJECTIVE：To optimize the formul ation of Polygala japonica cream，and to evaluate the quality of prepared cream. METHODS ：With centrifugal stability ，heat resistance stability and viscosity as evaluation indexes ，the weight coefficient was determined by analytic hierarchy process （AHP），criteria importance through intercriteria correlation （CRITIC）method and mixed weighted AHP-CRITIC ，and the comprehensive score was calculated. The amount of octadecyl alcohol ，hexadecanol and mixed emulsifier （polysorbate 60 mixed with glycerin monostearate at the mass ratio of 2.82）in the formulation of P. japonica cream were screened by central composite design-response surface methodology. The optimized formulation was validated. P. japonica cream prepared by the optimal preparation was evaluated in terms of apperance ，particle，pH，stability and rheological characteristics. RESULTS ：The weight coefficients of centrifugal stability ，heat resistance stability and viscosity were 0.428 5， 0.415 6 and 0.155 9 respectively，according to the mixed weighted AHP-CRITIC. The optimal formulations were 1.96 g of hexadecyl alcohol ，5.17 g of octadecyl alcohol ，2.48 g of mixed emulsifier ，1.83 g of polysorbate 60，0.65 g of glyceride monostearate，1 g of benzyl alcohol ，5 g of propylene glycol ，6 g of isopropyl myristate and 5 g of P. japonica extract，and then added water to 100 g. Prepared cream was a light yellow fluid paste with particle size of 0.5-2.5 μm and pH value of 6.5；the results of centrifugal test ，heat resistance test and cold resistance stability test showed that the cream had no oil-water separation or thickened paste. The prepared cream was shear-thinning non-Newtonian fluid. CONCLUSIONS ：P. japonica cream is prepared successfully，which shows good apperance ，particle，acidity and stability.