CHANGE IN APPLE FRUIT VOLATILES AFTER STORAGE IN ATMOSPHERES INDUCING ANAEROBIC METABOLISM

Delicious apple fruit (Malus domestica Borkh.) stored in 0.05% O2/0.2% CO2, 1-degrees-C, for 30 days developed large concentrations of ethanol and acetaldehyde. The accumulation of products of anaerobic metabolism resulted in altered synthesis of fruit volatiles, most notably a large increase in the amount of ethyl acetate. Several ethyl esters, not detectable from control fruit, were present in headspace samples collected from apples stored in 0.05% O2/0.2% CO2 including ethyl propanoate, ethyl butyrate, ethyl 2-methylbutyrate, ethyl hexanoate, ethyl heptanoate, and ethyl octanoate. The increase in the emission of these compounds was accompanied by a decrease in the amounts of other esters requiring the same carboxylic acid group for synthesis.