Effect of acetic acid hydrolysis on the characteristics of water soluble chitosan

Abstract

Chitosan is a derivative product of chitin deacetylation and has many functions in food industry. However, it has limitation on application caused by low solubility in water. In order to increase the solubility in water, the hydrolysis using acetic acid was performed to reduce the molecular weight. The concentration of acetic acid, temperature of hydrolysis and hydrolysis time related to the solubility were investigated. Hydrolysis using 5% acetic acid was able to produce water soluble chitosan (WSC) with a molecular weight of 198.64 kDa and 46.10% solubility in water. WSC that was obtained at 60 oC for 90 min of hydrolysis process in 5% acetic acid had characteristics of viscosity, molecular weight, solubility in water and deacetylation degree were 0.85 cP, 166.34 kDa, 53.66% and 92.92%, respectively.