Modified atmosphere and controlled atmosphere are two food preservation methods used to increase the shelf life of food products. However, although they have similarities, they are two different techniques that involve different packaging processes.
Predominantly used for packaging perishable foods, these two systems require the use of specific food packaging products, machines and food additives. We look at what modified atmosphere and controlled atmosphere mean and what the main differences and uses are in the food industry.
What controlled atmosphere means for food
Controlled atmosphere is a food product packaging technique that protects foods from oxidation and prolongs their shelf life, preventing the products from coming into direct contact with oxygen. In the controlled atmosphere packaging process, air is removed from the inside of the packaging and replaced with a mixture of gases. Then, the packaging is hermetically sealed.
In this method, the atmosphere inside the packaging is controlled using a specific mixture of gases according to the type of product and the storage performance. The gases that can be used in the mixture include:
- Oxygen
- Carbon dioxide
- Hydrogen
- Nitrogen
After the initial processing, the mixture of gases remains stable over time, generally at a temperature of around 3–4°C, and allows the product to be preserved for up to 6 to 8 months. The gases used are considered additives, so they are identified by standardized initials used across Europe (e.g. E290 for carbon dioxide, E941 for nitrogen and E948 for oxygen).
Modified and controlled atmosphere: what are the differences?
There are substantial differences between controlled atmosphere and modified atmosphere. With controlled atmosphere, the air is replaced with a mixture of gases, while with modified atmosphere the concentration of oxygen inside the packaging is reduced (and sometimes the concentration of carbon dioxide is increased) to extend the shelf life of perishable food products and combat the proliferation of microorganisms.
Modified or protective atmosphere packaging does not control the mixture of gases, and the interaction between the food and the atmosphere inside changes the original mixture during storage. Therefore, in the modified atmosphere, the food breathes and interacts with the gases inside in the packaging, while in the controlled atmosphere, the mixture of gases remains stable and uniform.
Which is better, controlled or modified atmosphere packaging?
There isn’t actually one technique that is better than the other between controlled and modified atmosphere. Both are useful in certain circumstances and should be used in specific contexts. Generally, controlled atmosphere is used especially for food preservation in cold storage or containers, using special sensors and tools to monitor the mixture of gases.
For food packaging, on the other hand, modified or protective atmosphere is often used, for example for the packaging of meat, fish, vegetable products and fresh foods like fruit. This technique is also used for cheese packaging, the packaging of baked products and pasta packaging, including fresh filled pasta.
Volmar offers a wide range of high-quality solutions for protective atmosphere packaging, including vacuum-sealed packaging. This is professional packaging like laminated paper, pillow bags and flow packs or rigid films often made from composite materials, which are compatible with modified atmosphere packaging (MAP) systems.