Recent developments in gum edible coating applications for fruits and vegetables preservation: A review

Gums are a class of naturally occurring polysaccharides/carbohydrate polymers derived from renewable sources, which have the capacity to hydrate in water either by forming a gel or stabilizing emulsion systems. Among the substitutes recently considered to replace the application of petroleum-derived polymers against postharvest diseases and shelf life extension, gums and their derivatives have been considered as promising biocontrol products. Polysaccharide gum coatings provide a semipermeable barrier on the surface of produce to reduce respiration rate, weight loss and maintain the nutritional value. Gums have been used as excellent vehicles for active substances, also controlling the speed of diffusion of these, and improving the control of the maturation of fruit and vegetable. Additionally, plant extracts, essential oils, phenolic compounds, and vitamins can be incorporated into polysaccharides edible coatings in order to improve their mechanical barrier, antioxidant and antimicrobial properties. Gums have many advantages over the synthetic polymers, because they have been approved as GRAS by FAO, and their use is safe for the consumer and eco-friendly. This review aims to highlight the most relevant and current information in the use of polysaccharides in postharvest shelf life extension and preservation of overall quality of fruits and vegetables.