FISH WASTE, NOT A PROBLEM BUT A POSSIBLE SOLUTION: CHITOSAN EXTRACTS AND NEW PACKAGING POSSIBILITIES.

Abstract

The fishing industry is one of the oldest industries in Europe and also one of the most important economic resources in the Mediterranean area. However, to date, in addition to creating considerable economic wealth, the various sectors (markets, restaurants, shops, etc.) also create significant levels of fish waste. If not processed or recycled adequately, these waste streams can lead to environmental degradation and severe pollution (Gao et al., 2018). Although today fish waste is considered a potential resource to generate high-added value, current practices in the fishing industry do not fully exploit its biological potential. Amongst the various possibilities for reuse, the production of biodegradable polymers emerges as a point of considerable interest for the food industry in the development of packaging materials and in order to improve the quality and appearance of food products (Elsabee and Abdou, 2013). In this context, chitosan, a polysaccharide of natural origin, has been experimentally used to produce edible packaging films due to its antimicrobial activity and physical-mechanical properties (Peng and Li, 2014). It is obtained from chitin, one of the most abundant natural polysaccharides and a typical component of the exoskeleton of crustaceans, molluscs and insects, and fungal cell walls (Sivaramakrishna et al., 2020). Although good progress has been made in the production of chitosan biofilms, the type of packaging that can be obtained still needs to be perfected. This study, supported by the EU Interreg Italia-Malta V-A project Bythos – Biotechnologies for Human Health and Blue Growth (C1-1.1-9), shows the preliminary results from the production of chitosan biofilms and the potential for improvement. For the first time, chitosan biofilms were produced from the head part of the exoskeleton of Aristaeomorpha foliacea, a species of considerable economic interest in the Sicilian fishing sector. Methods of extraction and purification of chitosan were developed, and the biological activities of the biofilms were evaluated. The biofilms demonstrated an antibacterial potential against Gram-positive and Gram-negative indicator strains, thus constituting a possible resource against microbial and chemical contamination in the food industries. Although further research is needed to identify new packaging methods and natural compounds that could improve the physical properties and antibacterial/antioxidant activities of the films, the possibility to reuse waste from this leading species in the Sicilian economy plays a significant role from the perspective of sustainable development and green economy.