Effect of two edible coatings with different permeability characteristics on mango (Mangifera indica L.) ripening during storage

Two types of fruit coatings were tested for their effect on external and internal mango fruit atmospheres and quality factors during simulated commercial storage at 10 or 15 degrees C with 90-99% RH followed by simulated marketing conditions of 20 degrees C with 56% RH. One coating was polysaccharide-based while the other had carnauba wax as the main ingredient. These two coatings exhibited markedly different O-2 permeability characteristics under laboratory conditions. This confirmed what has been reported in the literature, that polysaccharide coatings are less permeable to respiratory gases, such as O-2, and more permeable to water vapor compared to carnauba wax. When applied to fruit under simulated commercial conditions, however, the difference between the coatings in permeance to respiratory gases were much reduced, most likely due to the high humidity during chilled storage. Both coatings created modified atmospheres, reduced decay, and improved appearance by imparting a subtle shine; but only the polysaccharide coating delayed ripening and increased concentrations of flavor volatiles. The carnauba wax coating significantly reduced water loss compared to uncoated and polysaccharide-coating treatments. (C) 1999 Elsevier Science B.V. All rights reserved.