Controlled Atmosphere Cold Storage

Controlled Atmosphere (CA) is used to buffer fresh produce immediately after harvest, making it available for longer at the market, at better selling prices. It is a storage method in which the concentrations of oxygen and carbon dioxide, as well as the temperature and humidity, are optimized in gastight cold stores. CA is often used for long-term storage of apples, pears, kiwis and various types of berries, but also for example for cabbages and green beans. The combination of an altered gas atmosphere and a lowered temperature prevents loss of quality due to ripening, moisture loss, and storage aberrations. The oxygen level is greatly reduced and carbon dioxide is increased as much as possible. Outside air consists of approximately 78% nitrogen (N₂), 21% oxygen (O₂), 0.045% carbon dioxide (CO₂). CA lowers the oxygen level generally to 0.5-2.5%, depending on the type of product and the variety. CA conditions extend the shelf life of fruit and vegetables with a factor of 2 to 4, which means that apples, for example, can be stored all year round, and berry varieties can be stored for several months.

Sigma designs, installs and services CA equipment and control systems. But we also act as a consultant when it comes to cooling systems for fresh produce and the construction of cold stores. We offer wide capacity range of storage system starting from 500 MT to 50,000 MT and above.