Preparation of biodegradable antibacterial, antioxidant, and pH- sensitive hydrogel films based on carboxymethyl cellulose and collagen for fish freshness monitoring

Abstract From ancient times until present day, preservation of aliments as long as possible has been of particular importance. For this, it is necessary to limit as much as possible the multiplication and proliferation of micro-organisms on food which make it toxic for human consumption. Extending the life of a product is the area where packaging can contribute the most to reducing food waste. There are various types of food packaging. Not all are equal in terms of risk. Nevertheless, each of them has its own faults and contaminants. Among the lot of promising materials are so-called “intelligent” packaging. One of the most crucial points is to design packaging based on natural and biodegradable materials that do not harm the environment after use. Additional innovation is the introduction of antibacterial and antioxidants properties into food packaging materials. Indeed, in this research work, we prepared an active antimicrobial and antioxidant biodegradable blended hydrogel films based on natural polymers such as carboxymethyl cellulose (CMC), collagen (COL) incorporated with active natural agents such as Eucalyptus leaf extract (ELE) or quercetin (QCT). The effects of eucalyptus extracts and quercetin on the physical and functional properties of the films, including morphology and structure, pH sensitivity, antioxidant and antibacterial properties were investigated. For the evaluation of the freshness of fish, the total volatile basic nitrogen (TVB-N) content was determined. The results of TVB-N, antibacterial and antioxidant activities, and observed color change indicate that the prepared films have a high potential for preserving fish meat and can be used as an indicator to monitor the freshness of fish.