Abstract

Development and Characterization of Antimicrobial Packaging Films

Zinash Assefa and Shimelis Admassu

The purpose of this work was to develop and study the effect of bioactive component towards the inhibition of microbial activities of films; aiming to assess their performance in employing for antimicrobial packaging film. In order to achieve appropriate inhibition effect of the antimicrobial agent, the structure of the films was changed from a highly asymmetric and porous to the dense by the modulation of the composition of the initial casting solution. The results on inhibition effect of starch-based films prepared from 90-100% (w/w) starch and 0-10% (w/w) bioactive component (saponin) revealed antimicrobial activity in a growth of bacteria (Escherichia coli, Salmonella typhi and Entrobacter erogenous). An increase in saponins concentration in the casting solution decreased the growth of microorganisms and the inhibition activities of the films increased. Results on moisture content, transparency, swelling, solubility and mechanical properties of the films at different concentrations of bioactive component and levels of film thickness reveled significance differences at p<0.05. The film with 10% saponins concentration showed better inhibition effect in a growth of Salmonella typhi, E. erogenous and E. coli for 0.02 and 0.04mm film thickness. The maximum antimicrobial activities and tensile strength of the films increased with an increase in an amount of the bioactive component in the casting solution. In conclusion, this study confirms that the saponins extracted from haricot bean seeds and incorporated in the films had antibacterial activity on pathogenic bacteria. The films may be used for food packaging that are extremely vulnerable to microbial growth or directly used as a surface coating on perishablefruits and vegetables consecutively to augment their microbial safety and extend shelf stability of food products. Undoubtedly, this area of research holds considerable potential on food delivery systems.