Research conducted by Air Products has shown that the amount of carbon dioxide (CO2) used in Modified Atmosphere Packaging (MAP) can be reduced to as low as 20% while still maintaining the ability to extend the shelf life of food products.

MAP is an established and effective technology, proven to extend the shelf life of packaged foods without the need for added preservatives. It works by replacing the atmospheric air present in food packaging with CO2, nitrogen or oxygen, either on their own or in combination, depending on the product.

The role of CO2 is to inhibit the growth of microorganisms and extended the shelf life.

Air Products carried out the research to clarify the relationship between shelf life and the reduction of CO2 in the MAP mix. The research evaluated several gas mixtures with differing CO2 concentrations to determine the lowest CO2 content able to prolong food shelf life.

The study tested four gas mixtures with CO2 concentrations of 10, 20, 30 and 40% balanced with nitrogen, and one control, using air, and measured their impact on a sample of ready-to-eat meatballs inoculated with microorganisms.

Findings from the research showed that the longest shelf life of at least 28 days was achieved using a CO2 ratio of between 30%-40%. When the level of CO2 was dropped to 20%, a maximum shelf life of 21 days was achieved, while CO2 concentrations of below 20 % delivered shelf life results equal to that of meatballs packed in air, which is typically limited to a maximum of 14 days.

Neil Hansford, Industrial Cryogenic and Food Expert at Air Products said: “Understanding the impact that changes inCO2 concentration can have on the shelf life of a product has always been of interest to food producers.”

“Thanks to this research, a greater understanding of the link between CO2 concentration and shelf life has been established. Food producers can be assured that even relatively low levels of CO2 can still have a positive impact of shelf life.”