THE EFFECTS OF TEMPERATURE, OXYGEN AND CARBON DIOXIDE ON TIE STORAGE QUALITY OF `YORK IMPERIAL' APPLES
York Imperial is an important processing apple cultivar in the mid-Atlantic region and is often stored for up to eleven months. This experiment was designed to further examine the optimum CA storage conditions for this cultivar. Six orchards were used as statistical blocks. The factorial experiment was set up with 2 temperatures (0 and 2C), 2 oxygen (1 and 2%) and 3 carbon dioxide concentrations (2,3.5 and 5%). Sample size was 20 fruit at all analysis periods (at harvest, 4, 6, and 8 months). The apples were stored in a recirculating CA research facility and evaluated for firmness, soluble solids and weight loss. In the overall statistical analysis, orchard blocks, harvest dates and storage times significantly influenced all 3 quality parameters. Differences between blocks at harvest were substantial with firmness ranging from 9.5 to 11.3 kg and the soluble solids ranging from 12.8 to 14.8%. At the third storage removal (8 months), low oxygen increased firmness and decreased weight loss during storage while at the lower temperature, apples were firmer, had higher soluble solids and less weight loss than at the higher temperature. Although statistically significant, the differences may not be commercially important Block differences were generally maintained throughout storage.