PERMEABILITY OF DIFFERENT WAX COATINGS AND THEIR EFFECT ON CITRUS-FRUIT QUALITY

Gas and water vapor permeability (WVTR) of seven coatings, used commer cially for citrus, was determined by coating these on highly permeable films. Oranges and mandarins were coated with the same seven coatings , and weight loss, appearance, internal gas composition, presence of e thanol and acetaldehyde, and flavor of these fruits were determined. T here was a relationship between low concentrations of oxygen, which le ad to off-flavors, and the presence of ethanol and acetaldehyde the fr uit. There was also a relationship between WVTR and weight loss of the fruit with most coatings, but no correlation between CO2 and O-2 perm eability of the coatings and concentration of these gases in the fruit . The above findings were validated in a semi-industrial trial.