Development of Biodegradable Films from Marine Ingredients Incorporated with Natural Antimicrobial Agents for Food Packaging

Abstract

The fish gelatin obtained from processed fish waste was used in the development of biodegradable film. The film was obtained by dissolving the fish gelatin with distilled water as a solvent and glycerol as a plasticizer. The developed film was stable and exhibited good tensile strength. Irish moss-I-Carrageenan and laminarin were added to improve the properties of the developed film. The films were also incorporated with micro- and nano-forms of curcumin to have antimicrobial properties. The developed films were characterised following the standard protocols. The developed films with incorporated curcumin extract exhibited enhanced mechanical properties. It was observed that there was 71.4% increase in Nano-curcumin Fish Gelatin Film (NCFGF) film compared to Fish Gelatin Film (FGF). Marginal decrease in the water vapour transmission rate (WVTR) of the film was observed. The scanning electron microscopic (SEM) images of the curcumin incorporated film showed the non-uniform distribution of the curcumin particles, while, in the nano-curcumin film, there was a uniform distribution with tubular pattern formation. FTIR studies showed that the some of the peaks were shifted to higher or lower wave numbers with the incorporation of curcumin and nano-curcumin. The incorporation of curcumin and nano-curcumin slightly transformed the molecular structure and intermolecular interactions in the film. There was increase in glass transition temperature as compared to the pure gelatin film, indicating that fish gelatin film and fish gelatin films added with curcumin and nano-curcumin particles have good miscibility. Shelf life studies of pangasius fish fillet packaged in the developed films showed less change in colour in curcumin incorporated film compared to the control. The microbial analysis showed decrease in total plate count (TPC) of FGF, CFGF, and NCFGF films. Yeast and molds count showed trends similar to TPC. The shelf life of pangasius fish fillets was of 8 days in the control, 10 days in FGF, 12 days in CFGF, and 15 days in NCFGF. Hence, NCFGF film can be used to pack food products like pangasius fish fillet to increase the shelf life.