Bitter pit reduction in ‘Cox's Orange Pippin’ apples by controlled and modified atmosphere storage

Abstract

Controlled and modified atmospheres reduced bitter pit in New Zealand ‘Cox's Orange Pippin’ apples stored for 5 weeks at 2°C. Fruit from orchards that had received calcium sprays during the season were stored in an integral container maintained with a gas atmosphere of 3% CO 2 plus 3% O 2, and had less than 6% bitter pit. In comparison, air-stored fruit from the same orchards had up to 26% bitter pit. Polyethylene bags containing different numbers of 9-mm holes were tested for their effectiveness in influencing bitter pit development. The incidence of bitter pit that developed during storage was progressively reduced from 50% to less than 5% as the number of holes per bag decreased. Fruit in polybags had less weight loss, higher firmness and improved quality compared with air-stored fruit. Practical problems relating to commercial use of polybags for bitter pit control are discussed.