Dye Binding Properties of Chitin and Chitosan

Abstract

ABSTRACT Chitin (β (1°4)‐N‐acetyl‐D‐glucosamine) and chitosan (deacetylated chitin) are currently available in large quantities as waste products and by‐products of the shellfish industry. Their potential as carriers for food additives was studied. Significant correlations were found between dye concentration ranging from 0.2–1.6 mg dye (FD&C Red No. 40) per g chitin or chitosan and dye‐binding capacity of chitin or chitosan. Within a pH range of 2.0–7.0, dye‐binding capacity of chitin was stable. Chitosan gelled below a pH of 5.5 and could not be evaluated but its dye‐binding capacity was constant between pH 7.0 and 5.5. Above pH 7.0 dye‐binding capacity decreased for chitin as well as for chitosan but between pH 2.0 and 6.0 no dye was released from dyed chitin containing 0.77 mg dye/g chitin.