Changes in firmness of apples affected by moisture loss during storage

SummaryApples (Malus domestica Bork. cv. 'Delicious Pilafa') from three cultivation periods (1999, 2000 and 2001) were stored in two traditional warehouses and in two controlled environment rooms (10°C; 85% RH and 0°C; 90% RH) to investigate the relationship between change in fruit firmness and loss of moisture. By regression analysis, a square-root model was found to be most suitable to describe the change in firmness with time or dehydration, and dehydration over time, for all 'treatment storage period' combinations. However, no single relation was found for change in firmness or dehydration against time, probably due to the highly variable storage conditions. A single equation describing change in firmness against dehydration was derived, for all the storage conditions studied. This relationship may be useful for quality assessment of cv. 'Delicious Pilafa' apples during storage.