ELECTRONIC SENSING OF AROMATIC VOLATILES FOR QUALITY SORTING OF BLUEBERRIES

An electronic sniffer using semi-conductor gas sensors that nondestruc tively measured aromatic volatile gas emissions from fruit was develop ed to assess blueberry quality. The sniffer detected soft and damaged fruit in packaged containers at a 5% level of damage and distinguished four of five fruit ripeness classes: (1) mature-green and green-pink; (2) blue-pink; (3) blue; and (4) ripe fruit. Sniffer response increas ed as fruit ripened, as did total concentration of aromatic volatiles. Sniffer response correlated with berry firmness, pH, titratable acidi ty, and color, and detected differences among 10 cultivars, as did imp act response analysis. The electronic sniffer is rapid, nondestructive and may be used to sort and quality check for presence of unripe or d amaged fruit in closed packs of fresh berries.