Optimization of the methods for extraction of chitin in crab shell and preparation of chitosan

摘要

A combination of both acid and alkali treatments was used to extract chitin from crab shell in this study. Then a three factors (NaOH) solution concentration, reaction time, reaction temperature) and three lev- els (35, 45, 55; 2, 6, 10; 70, 105, 140) L_9 (3~4) orthogonal experiment design is further adopted to conduct a de-acetyl treatment to prepare chitosan by considering the viscosity and de-acetyl degree of the chitosan as the main performance indexes.