EFFECTS OF OXYGEN CONCENTRATION ON ETHYLENE SYNTHESIS AND ACTION IN STORED APPLE FRUITS

The response of apples (Malus domestica Borkh) cv. 'Cox's Orange Pippin' to removal of ethylene from storage atmospheres containing from 0.5% to 2%0₂ in flowing gas streams was examined in two seasons.

Both ethylene production and concentrations within the core cavity were decreased by lowering the oxygen concentration. The presence of an ethylene absorbent in containers also reduced internal ethylene concentration and the lower the oxygen concentrations the smaller the difference between store concentrations and levels of ethylene within the core cavity.

In these experiments, neither flesh firmness nor peel colour were affected by the presence of an ethylene absorbent in containers in either season. As this was not in agreement with trials using a 'static' system it was concluded that simulation of commercial stores using 'flow' systems may give misleading results.