Chitosan for food packaging: Recent advances in active and intelligent films

The massive and uncontrolled use of food packaging derived from petroleum-based plastics has created a serious environmental problem. Hence, the food packaging industry needs to develop packaging from biodegradable polymers. Among the many raw materials studied in the literature, chitosan is one of the most abundant polysaccharides in the nature. Chitosan has attracted attention due to its non-toxicity, antimicrobial, and antifungal properties. Because of this, chitosan is considered a perfect material for the development of films for food use. In this review, recent studies on active and/or intelligent chitosan-based films has been evaluated. Active packaging maintains or improves the condition of packaged food or extends its shelf-life meanwhile intelligent packaging monitors the condition of packaged food or the environment surrounding the food. The effect of the addition of active compounds on the mechanical, barrier and functional properties of chitosan-based films has been assessed. The antimicrobial and antioxidant activity, as well as the potential application of these active and intelligent composite films have also been revised. Literature shows that the presence of phenolic compounds improves both mechanical and barrier properties of chitosan films. The antimicrobial and antioxidant capacity of the films improved significantly by the addition of essential oils, phenolic compounds, and other fruit extracts. Intelligent pH-indicator chitosan-based films have been extensively studied. Further research on chitosan and its combinations with other materials is needed to study which type of foodstuffs could be in contact with chitosan packaging.