Edible Coatings and Films for Preparation of Grapevine By-Product Infusions and in Freshly Processed Products

Abstract

The wine industry is responsible for a considerable part of environmental problems because of the large amounts of residues. However, several studies have shown these wine industry residues, such as grapes, skins, seeds, and leaves, represent a complex matrix of bio-compounds, such as phenolic compounds, flavonoids, procyanidins, anthocyanins, tannins, catechin, quercetin, kaempferol, and trans-resveratrol, and nutrients such as vitamin C. These wine and vine by-products or their extracts have antioxidant, anti-inflammatory, cardioprotective, anti-aging, and anti-cancer activities, which benefit human health. Due to processing (drying, mincing), some vine by-products are perishable and may present a short shelf-life. The production of the developed products can be achieved by using edible films and coatings. The use of edible coatings is an innovative method for preservation in postharvest. This technique is gaining popularity since it is easy to apply, environmentally friendly, and highly efficient. Indeed, the application of edible layers on lightly processed foods can preserve their essential nutrients and protect them from attack by microorganisms in addition to preserving their appearance by maintaining their original color, flavor, and texture. More research must be carried out to optimize coating formulations to achieve the highest possible quality. This review aims to elucidate several techniques of making edible coatings and the different types of edible coatings that can be used in the preparation of grape by-products for foods and drinks, namely grapevine infusions made with dried minced grapes, dried minced grape pomaces, and in freshly processed products. Besides the usually used coating materials, such as chitosan, agar-agar, gelatin, and alginate, other compounds will also be discussed, namely guar gum, soy lecithin, maltodextrin, inulin, and propolis.