Natural Additives in Bioactive Edible Films and Coatings: Functionality and Applications in Foods

Abstract

Incorporation of natural additives to active packaging systems or biopolymer-based edible films can modify the film structure and, as a result, modify their functionality and application to foods. This paper reviews the effect of the incorporation of natural additives from plant extracts or their isolated active compounds and vitamins on the functionality of edible films and the application of these films to foods. The final functionality of edible films is related to their bioactive properties (such as antioxidant, antimicrobial, and antibrowning activities) and functional properties (such as barrier to oxygen, carbon dioxide, and UV–vis light); water vapor permeability; tensile stress; elongation at break; and physical properties (such as opacity and color). Several categories of natural antioxidants found in plant, spices, and herbs (organic acids, plant natural extracts, and plant essential oils) have been incorporated into edible films and coatings, resulting in an improvement of the bioactive properties of the films. However, a wide range of plant natural sources with bioactive properties has not yet been characterized with respect to their ability to be applied directly on foods and used to develop active packaging or biopolymer-based edible films for preserving and adding value to foods. In addition, in vivo studies of the use of bioactive films to preserve the quality, shelf life, and nutritional value of foods remain limited.