Controlled atmosphere (CA) storage delays ripening and senescence changes in apples and preserves many important quality attributes such as firmness, acidity and soluble solids (sugar) concentration. However, one negative consequence of the use of CA storage for prolonged periods is the reduced production of compounds that contribute to aroma and flavour.
In order to increase the flavour of Cox apples:
- Harvesting should not be earlier than is necessary to achieve the period of storage that is required. Delay in harvesting maximises flavour potential, but harvesting too late reduces storage life and has adverse effects on fruit texture.
- Reserve the use of ultra-low oxygen or ULO (1.2% O2) for medium or long-term storage provided that the firmness of fruit stored short-term is adequate for the requirements of the market.
- Raise the oxygen concentration in ULO stores to 2% O2 4-5 weeks prior to opening the store provided that firmness is adequate for the requirements of the market.
- Practices to maximise flavour in stored Cox apples should only be implemented when there is unlikely to be any detrimental effects on other quality parameters. Full knowledge of the condition of the fruit in store is essential in the decision making process which can be achieved by regular store monitoring.
- The advice provided above on conditioning is likely to be appropriate to all dessert cultivars stored in ULO conditions.