This review discusses the latest advances in the composition of gelatin-based edible films and coatings, including nanoparticle addition, and their properties are reviewed along their potential for application in the food packaging industry. Gelatin is an important biopolymer derived from collagen and is extensively used by various industries because of its technological and functional properties. Nowadays, a very wide range of components are available to be included as additives to improve its properties, as well as its applications and future potential. Antimicrobials, antioxidants and other agents are detailed due to the fact that an increasing awareness among consumers regarding healthy lifestyle has promoted research into novel techniques and additives to prolong the shelf life of food products. Thanks to its ability to improve global food quality, gelatin has been particularly considered in food preservation of meat and fish products, among others.

The interest for the development of new active packaging materials has rapidly increased in the last few years. Antimicrobial active packaging is a potential alternative to protect perishable products during their preparation, storage and distribution to increase their shelf-life by reducing bacterial and fungal growth. This review underlines the most recent trends in the use of new edible coatings enriched with antimicrobial agents to reduce the growth of different microorganisms, such as Gram-negative and Gram-positive bacteria, molds and yeasts. The application of edible biopolymers directly extracted from biomass (proteins, lipids and polysaccharides) or their combinations, by themselves or enriched with natural extracts, essential oils, bacteriocins, metals or enzyme systems, such as lactoperoxidase, have shown interesting properties to reduce the contamination and decomposition of perishable food products, mainly fish, meat, fruits and vegetables. These formulations can be also applied to food products to control gas exchange, moisture permeation and oxidation processes.

The migration of antioxidant (AO) agents, carvacrol and thymol, from polypropylene (PP) packaging films containing the studied compounds at 80 g/kg separately and an equimolar mixture of them into food simulants was investigated. Fast and reliable analytical procedures were developed and validated for the analysis of the studied AOs in food simulants. For aqueous food simulants, solid phase extraction followed by GC–MS analysis was performed. Fatty food simulants were directly analysed by GC–MS and HPLC-UV for isooctane and ethanol 950 mL/L, respectively. The release of AOs from the films was dependent on the type of food stimulant and AO incorporated. In particular, high levels of migration were obtained for both AOs into isooctane, showing thymol higher migration. The release kinetics of AOs from PP films showed a Fichian behaviour with diffusion coefficients ranging from 1 to 2 × 10−14 m2/s; except for the diffusion into isooctane where 4-6 higher values were obtained. The antioxidant activity of migration extracts was confirmed by the DPPH method, showing thymol a higher antioxidant capacity especially into isooctane with a 42.2% of inhibition. The obtained results suggest that carvacrol and thymol show a potential use as AOs for active packaging for extending the shelf-life of food products.Spanish Ministry of Economy and Competitiveness (MAT-2011-28640-C02-01). Marina Ramos would like to thank University of Alicante (Spain) for UAFPU2011-48539721S predoctoral research grant