Classification of impacted blueberries during storage using an electronic nose

BACKGROUND: An electronic nose (EN) was used to determine the effect of repeated impacts on changes in volatile characteristics of fresh blueberries during storage. Hand-harvested 'Misty' blueberries (Vaccinium corymbosum) were treated either as (1) undropped (control) fruits, (2) fruits poured six times from a picking bucket 200 mm into a plastic field lug or (3) fruits dropped as above ten times onto a steel surface. Fruits from all treatments were stored in vented polystyrene clamshell containers at 2 degrees C and 95% relative humidity. RESULTS: Repeated impacts caused no skin rupture or leakage after treatment or during storage. EN data were subjected to discriminant function analysis to classify samples by treatment at days 0, 2, 10, 17 and 24 (n = 5 per treatment). Correct classification rates (CCRs) for days 0, 2, 10, 17 and 24 were 0, 100, 100, 100 and 100% respectively. On day 0 there was no significant difference in sample volatiles, and CCRs for all treatments and storage times ranged from 80 to 100%. Cross-validation rates for different treatments and storage times ranged from 75 to 100%. CONCLUSION: The EN could be a useful tool to estimate the effect of impacts incurred during blueberry handling on quality based on changes in volatile characteristics. (C) 2011 Society of Chemical Industry