Investigation of deproteinzation and decoloration technology for polysaccharide from mango pomace

The different methods of removing protein and pigment of polysaccharide from mango pomace were studied. Nine methods were used in our study to select the best deproteinization method with the rate of deproteinization and polysaccharide retention as indexes, including TCA method, TCA-n-butanol method, Sevage method, HCl method, papain method, TCA+Sevage method, papain+TCA method, papain+Sevage method, and papain+TCA-n-butanol method. Then, activated carbon was used to study the decoloration of polysaccharide solutions after removal of protein with the rate of decoloration and polysaccharide retention as indexes, the best conditions were optimized by orthogonal test on the basis of single factor experiments. The results indicated that the method of TCA-n-butanol was found to be most effective for mango pomace polysaccharide and its operation was:the volume ratio of TCA-n-butanol to sample liquid 2:1, the volume ratio of TCA to n-butanol 1:20, and the shaking time 2 h. Under this condition, the deproteinization rate and polysaccharide retention rate were 90.08% and 94.40%, respectively. The optimum decoloration conditions of activated carbon were added 1.5% active carbon at sample pH3.0, with temperature at 50℃ for 75 min, the decolorization rate and the retention rate of polysaccharide were 70.98% and 92.77%, respectively. The optimal method was feasible and can be used for deproteinization and decolorization of polysaccharide from mango pomace.