Optimization of the biocide properties of chitosan for its application in the design of active films of interest in the food area

• Published in: Food hydrocolloids Vol. 23; no. 3; pp. 913 - 921
• Main Authors: Fernandez-Saiz, P., Lagaron, J.M., Ocio, M.J.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.05.2009; [New York, NY]: Elsevier Science; Elsevier
• Subjects: accuracy; active films; Active packaging; Antimicrobial properties; Autoclaves; biocide properties; Biocides; Biological and medical sciences; Biopolymers; Chitosan; coatings; culture media; edible films; experimental design; Food additives; Food industries; Food microbiology; food packaging; food pathogens; Foods; Fundamental and applied biological sciences. Psychology; General aspects; glucosamine; laboratory techniques; measurement; Microorganisms; Nutrients; Optimization; protonated glucosamine; reliability; reproducibility; Salmonella; Staphylococcus aureus; sterilizing; temperature; thickness; Chitosan; Antimicrobial properties; Biopolymers; Active packaging; Film; Biopolymer; Conditioning; Antimicrobial agent; Optimization
• ISSN: 0268-005X; 1873-7137
• DOI: 10.1016/j.foodhyd.2008.06.001

The influence on biocide performance of some unprecedented physicochemical features of chitosan cast films such as film thickness, pH of the nutrient broth, film neutralization, film autoclave sterilization and temperature exposure were analyzed against Staphylococcus aureus and in some experiments also against Salmonella spp. The work demonstrates for the first time the influence of the release or positive migration of protonated glucosamine fractions from the biopolymer into the microbial culture as the responsible event for the antimicrobial performance of the biopolymer under the studied conditions. From the results, a reliable and reproducible method for the determination of the bactericidal activity of chitosan-based films was developed in an attempt to standardize the testing conditions for the optimum design of active antimicrobial food packaging films and coating applications.