Chitosan can be used as adhesive, moisturizing agent, clarifying agent, filling agent, emulsifier, polishing agent and thickening
stabilizer in food industry; as a functional oligosaccharide, it can reduce cholesterol, improve immunity, enhance disease
resistance and infection resistance of the body, especially has strong anti-tumor effect. Because of its rich resources and high
application value, it has been widely developed and used. Enzymatic or acid hydrolysis of shrimp or crab shell is often used to
extract chitosan in industry.