To ensure that fruit retains its consistency, ingredients, colour and flavour for as long as possible, it is stored in cold rooms at constantly low temperatures and high humidity. In addition to this, the composition of the storage atmosphere also has a significant influence on storage ability. Normal air consists of about 78 % nitrogen, 21 % oxygen, and small amounts of carbon dioxide (0.04 %) and various inert gases. In CA storage, the oxygen content in the storage room is reduced to a constantly low oxygen level by adding nitrogen, while at the same time the CO2 content is increased. This slows down the natural ripening process and maintains the quality of the fruit for a longer period of time.
The ideal composition of the atmosphere in CA storage depends on the particular fruit or vegetable type. Typical storage conditions are mostly in the following ranges:
- < 2% O2
- 0.5-5 °C
- 0-5% CO2
- up to 98% RH