Influence of Aeration Rate and Atmospheric Composition during Simulated Transit on Visual Quality and Off-odor Production by Broccoli1

Abstract Rates of air flow that permitted accumulation of CO 2 up to 18% and O 2 depletion to 1% or lower resulted in the development of off-odors in broccoli ( Brassica oleracea L. Italica group) following 8 days of simulated transit at 2.5°C Production of off-odors under restricted aeration was more pronounced at 0° than at 2.5° or 5°. Added CO 2 (10%) under normal aeration retarded yellowing and did not affect odor after 10 days at 2.5°, but after 17 days it resulted in a slight off-odor that disappeared upon holding in air at 5° for 2 days. O 2 levels of < 1% caused offensive off-odors that were still detectable after holding in air. After 9 days at 2.5° the effect of 1% O 2 + 20% CO 2 on off-odor production was similar to 0.5% O 2 alone. Respiration rate of broccoli flower heads held in 0.5% O 2 at 2.5° was about 60% of the rate in air.