Relationship of Stage of Ripeness and Holding Temperature to Decay Development of Blueberries1

Abstract

Abstract The relationship of holding temperature and stage of ripeness to decay development of blueberries (Vaccinium corymbosum L) was determined comparing 6 sets of 5 ripeness classes (light-sorted; 740-800 nm) stored at 1.1°, 10.0°, and 22.2°C. On each of 6 dates, 1 set (3 temperatures × 5 ripenesses × 4 replications) was removed from storage and sorted for decay. Regardless of cultivar or stage of ripeness, all blueberries stored at 22.2° decayed rapidly (within 5 days). Only when the blueberries were held at 1.1° did the time and expense of light-sorting appear economically justifiable; i.e., overripe berries (% soluble solids (SS)/% acid (Ac) ratio = 30) required about 12 days while just-ripe blue fruits (SS/Ac = 10) required about 32 days to develop 20% decay. Estimates of maximum degree of ripeness (SS/Ac) for fresh marketing (< 20% decay at retail) were made: Trans-Atlantic (up to 20,) transcontinental (up to 27), and local (⋜ 1200 km) (up to 30). Fruit riper than SS/Ac = 30 should be processed within 24 hours.