Characterization of chitosan meant for antimicrobial food packaging

Chitosan (CAS nº 9012-76-4) is a natural polysaccharide obtained by the partial deacetylation of chitin. It is a linear polymer of β (1-4) 2-acetamido-2-deoxy-D-glucose and 2-amino-2-deoxy-D-glucose in different proportions. Chitin is the most abundant polysaccharide after cellulose and the main source is the shells of crustaceans. It has been demonstrated that some important properties are directly related to the antimicrobial activity of chitosan. Some of these properties are the molecular weight (Mw), the degree of polymerisation (DP) and the degree of deacetylation (DD). In this work several analytical techniques (FTIR (Fourier-transform Infrared Spectroscopy), NMR (Nuclear Magnetic Resonance Spectroscopy) and SEM (Scanning Electron Microscopy)) were attempted to characterize two different samples obtained from shrimp waste. It can be concluded that sample 1 should be more suitable to be added as an active agent to a film.This work was funded under Project ‘Preparation of active packaging with antioxidant and antimicrobial activity based on astaxanthin and chitosan’ (PAPAAABAC, in Spanish PEACAABAQ) no. 95935 from FONCICYT C002-2008-1/ALA – 127 24