Airtight or closed storage systems are called “hermetic storage” or “closed storage”. This method makes it possible for insects and other aerobic organisms present in the product or the product itself to create an altered atmosphere by reducing oxygen (O2) and increasing carbon dioxide (CO2) along with respiratory metabolism. The respiratory activity of living organisms creates an atmosphere containing about 1-2% oxygen and about 20% carbon dioxide.
The success of hermetic storage practices in insect control is comparable to conventional disinfectants (over 99.9% kill rate) and the damage caused by insect activity is minimal (0.15% weight loss for a 15 month storage period).
Low O2 and high CO2 environment kills insects and small pests; inhibits the growth of aerobic fungi. High CO2 and reduced O2 levels generally preserve the quality of stored grain for a long time.
Products such as cereals, oilseeds, pulses, cocoa and coffee can be safely stored for long months in this way, while maintaining their high quality and preventing moisture and mycotoxin formation.