The 2012 ASHS Annual Conference

The composition and storage life of blackberries produced organically in North Carolina was determined for shiny (SB) and dull black (DB) ripeness stages. Subjective ratings, soluble solid content (SSC), titratable acidity (TA), total anthocyanin and phenolic contents, and antioxidant activity (FRAP) were determined in ‘Natchez’, ‘Ouachita’, and ‘Navaho’ blackberries held for 0 or 15 days at 1 °C and compared to fruit held for 13 days at 1 °C followed by 2 days at 20 °C. Weight loss was higher when berries were held at 20 °C for the last two days of storage. ‘Navaho’ had less leaky berries than ‘Ouachita’ or ‘Natchez’ at both storage temperatures. Decay incidence and softness were higher in ‘Natchez’ than in ‘Navaho’ and overall rating was highest for ‘Navaho’ blackberries. Lower leakage, decay incidence, and softness and higher overall rating were observed in SB than in DB fruit held at both storage temperatures. Storage condition, ripeness stage, and cultivar affected the composition of organic blackberries. SSC and TA were lower when berries were held at 20 °C for the last two days of storage compared to those held constantly at 1 °C. The TA was higher in SB fresh or stored berries compared to DB berries.  SSC, TA, and SSC to TA ratio were not different among cultivars before storage. However, SSC and TA were highest, and SSC to TA ratio was lowest, in ‘Navaho’ blackberry after storage. Total anthocyanin and phenolic contents and antioxidant activity of all berries were highest before storage. Neither ripeness stage or storage temperature greatly affected total anthocyanin, total phenolic content, or FRAP values. In this study, ‘Natchez’ had highest amounts of total phenolics and anthocyanin and ‘Ouachita’ lowest amounts (2609 vs. 2197 mg gallic acid equivalents/kg and 1284 vs. 944 mg cyanidin-3-glucoside equivalents/kg, respectively). The results suggest that organically grown ‘Natchez’, ‘Ouachita’, and ‘Navaho’ blackberries had excellent storage life and retained antioxidants when they were at the SB ripeness stage or stored constantly at low temperature.