Study on Extract of Pigment from Purple and Its Stability

[Objective]To study the extract methods and the stability of pigment from purple.[Method]The extraction conditions were obtained by single factor experiments,including the biggest absorption wavelength,organic solvent,extractive time and temperature;also the stability of pigment from purple were studied in this paper.[Result]The best extraction conditions of pigment from purple were showed as following: absorption wavelength was 530 nm,the best extraction solvents was citric acid at the concentration of 5%,the expected solid-liquid ratio was 1:10,1 h and 60℃for extraction.The research results showed that the stability and color of pigment was vulnerable to the effects of pH values.When in acidic environment,the pigment was found to have stable and light fastness nature,and the resistant to reinstate capacity of the pigment was stronger than its ability of resistant to oxidative.[Conclusion]These results may serve as basis to the extraction in large scale and application in industrial production.