ELEVATED CARBON-DIOXIDE STORAGE OF ANJOU PEARS USING PURGE-CONTROLLED ATMOSPHERE

'Anjou' pears (Pyrus communis L.) were placed in controlled-atmosphere (CA) storage immediately after harvest (<24 hours) or after a 10-day delay in refrigerated storage, and held there for 9 months at 1C. Oxygen in all atmospheres was 1.5% and CO2 was at either 1% or 3%. Atmospheres in the flow-through system were computer-controlled at +/- 0.1%. After removal from CA storage, pears were evaluated immediately and after ripening at 21C for 8 days. Pears stored in 3% CO2 were firmer, greener, and displayed less scald, internal breakdown, and stem-end decay than pears stored in 1% CO2. In addition, no internal discoloration of 'Anjou' pears was evident when held with 3% CO2. 'Anjou' pears held in 3% CO2 retained the ability to ripen after long-term storage. A 10-day delay in atmosphere establishment had little or no influence on the long-term keeping quality or ripening ability of 'Anjou' pears.