Preservation of aquatic food using edible films and coatings containing essential oils: a review

Edible films and coatings have recently received growing attention in the food packaging sector due to their protective ability from the external environment and biodegradability characteristic. Generally, any layer of biomaterial incorporated into food to prolong its shelf-life and that can be consumed along with the food with or without further peeling is defined as an edible film or coating. These biodegradable films improve mechanical properties, moisture and gas barriers, microbial protection, sensory perception, and the shelf-life of food products. In particular, films obtained from polysaccharides are characterized by better gas barrier properties, whereas proteins are known for their excellent mechanical properties. However, both polysaccharides and proteins show poor water barrier properties in films which can be improved by incorporating lipids as well as combining one or more hydrocolloids (proteins and polysaccharides). Moreover, essential oils (EOs) consist mainly of volatile components obtained from plants, which can be added to the film to improve antimicrobial and antioxidant properties. On the other hand, fishery products are highly perishable due to the combined action of chemical reaction, lipid oxidation, endogenous enzymes, and microbial growth. Cold storage and freezing with or without vacuum packaging are often used to preserve fishery products, but they do not always completely preserve quality. Therefore, this review aims to summarize the components and chemistry of edible films and coatings, and their application to aquatic food for quality preservation. Moreover, deterioration of aquatic food and how these films and coatings can improve antimicrobial, antioxidant, physical, and sensory properties are also discussed.