LAUSR

BACKGROUND Biodegradable and sustainable packaging with improved properties has increased interest in the food industry. Biopolymer materials based on renewable biomass can be used as an alternative version to conventional plastic packaging. A corn protein, zein, with its hydrophobic nature, possesses excellent film-forming properties. It can be used for making edible films as well as for producing nanofibrous layers. Combination with polysaccharide chitosan offers promising prospects in production of delivery systems for controlled release of active substances. The current trend is to minimize the content of chemical additives, thus essential oils are suitable alternative to synthetic antimicrobials. RESULTS This study aimed to develop various zein/chitosan-based film-forming solutions, films and coating with antimicrobial substances to prepare active food packaging. Thymol and three essential oils (thyme, cinnamon, oregano) have been applied as bioactive ingredients against bacteria, yeasts, and fungi. The incorporation of these natural active compounds led to a decrease in particle size in most film-forming solutions and a reduction of zeta potential compared to control. Release of the bioactive compound into an aqueous environment was proved during 24 hours by antimicrobial test. Zein/chitosan-based coating with thymol was applied on fresh strawberries. Microbiological analysis over ten days confirmed the efficient control of bacterial and fungal growth. CONCLUSION It can be concluded that zein/chitosan (7:1) systems are suitable as bioactive compound carriers to make a barrier and prevent moisture loss, ensuring microbial food quality and prolonging the shelf life of fruits. These systems can serve as sustainable active food packaging. This article is protected by copyright. All rights reserved.