Optimization of enzymolysis-alcohol extraction of violet cabbage pigment and its stability

The violet cabbage pigments were extracted from violet cabbage with methods of enzymolysis-alcohol extraction.The influence of enzyme sorts,ethanol concentration,enzyme con,liquid-solid ratio,extraction temperature and extraction time on the yield of the pigment were investigated. Based on single factor experiments,the extraction process of violet cabbage pigment was optimized by orthogonal test. In addition,the effects of temperature,pH and common food additives on the stability of the pigment were investigated. The results showed that the hemicellulose could improve the pigment yield,and the optimal technological parameters were fund as follows,hemicellulose dosage 3.2%(mL∶g),temperature45 ℃,enzymolysis time 2 h,water-material ratio 55∶1 (mL∶g),ethanol concentration 70%,under these conditions the maximum rate of the pigment was 13.45 mg/g.And there were bathochromic shifts from pH1 to 6 and hypsochromic shifts from pH8 to 12.The pigment decreased about 9.3% heated at 100 ℃ for 30 min.And potassium sorbate,DL-malic acid and sodium D-isoascorbate did not affect the pigment content,but lemon acid hadhyperchromic effect. Conclusion,the yield of the pigment extracted by enzymolysis-alcohol was the highest under the optimal conditions,and the pigments were sensitive to pH,relatively stableunder high temperature conditions,and it’s stability were not susceptible to common food additives.