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 in ternal mango fruit atmospheres and quality factors during simulated commerc ial storage at 10 or 15 degrees C with 90-99% RH followed by simulated mark eting conditions of 20 degrees C with 56% RH. One coating was polysaccharid e-based while the other had carnauba wax as the main ingredient. These two coatings exhibited markedly different O-2 permeability characteristics unde r laboratory conditions. This confirmed what has been reported in the liter ature, 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 d ifference 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 appearan ce by imparting a subtle shine; but only the polysaccharide coating delayed ripening and increased concentrations of flavor volatiles. The carnauba wa x coating significantly reduced water loss compared to uncoated and polysac charide-coating treatments. (C) 1999 Elsevier Science B.V. All rights reser ved.