Gelatin Films: Renewable Resource for Food Packaging

Abstract

The renewable origin of gelatin, high number of sources for easily extraction and the relatively low prices result in a very attractive biopolymer for application in food packaging. The acceptance of gelatin as "Generally Recognized as Safe" (GRAS) substance in the area of food additives by the U.S. Food and Drug Administration (FDA) together with its excellent film-forming ability, gel-forming properties around 35°C, excellent versatility due to its a-amino acid composition, abundance, low cost and biodegradability make gelatin an attractive protein in the design and development of functional films with potential application in the food sector. However, these beneficial characteristics are counterbalanced by the hydrophilic nature of gelatin, which imparts high moisture sensitivity to the derived films compromising their broader application. Numerous attempts have been undertaken to improve and modulate gelatin film properties to meet comparable performance to that of the conventional non-biodegradable plastics used in food packaging including chemical, physical and enzymatic cross-linking, plasticizing, compounding with other polymers, laminating and reinforcing with micro- and nano-size reinforcements. All these strategies offer the possibility to be incorporated to obtain a very wide range of tailor-made materials.