Internal Atmosphere of Onion Bulbs Stored at Various Oxygen Concentrations and Temperatures

Abstract

Abstract The internal atmosphere of onion (Allium cepa L.) bulbs after 3 months of storage at 20°C was 3.1% CO2/16.2% O2. Bulb size and sampling location within the bulb did not significantly influence the level of particular gaseous components. The equilibrium level of internal O2 was lowest at 30° and highest at 0° and was dependent on external O2 level. Wax applied to the root plate caused a dramatic reduction of internal O2 and elevation of CO2. There was less effect when only the neck of the bulb was waxed. The effect of waxing the base plate and neck was greater at 15° and 30° than at 0°.