Study on Pigment Extraction and Stability from Shizandra chinesis

Objective: To study the optimal extractive process and stability of the pigment extracted from Shizandra chinesis.Method: On the basis of single factor tests,the L9(34) orthogonal test was used in the optimization of technological parameters.The stability of pigment was discussed by the changes in absorbance.Result: The optimum extraction yield can be obtained by 45% ethanol heated up at 70℃ for 40 minutes with the material-solvent ratio of 1∶25(g/mL).The pigment holds good resistance to light.Also,the pigment is stable in acidic and alkalescency conditions,but discoloration emerges when pH is equal to or above 12.The pigment is relatively stable with carbohydrates and sodium chloride.Ascorbic acid and sodium sulfite have no adverse effects on the pigment but sodium benzoate and H2O2 do.Metallic ions Ca2+,Mg2+ and Na+ have no effect on the pigment,but Fe2+,Cu2+ and Al3+ have remarkable effects on it.