The difference between CAS, MAP and Vacuum Packaging

Posted on 23 April 2020

Drying, freezing, pasteurization and much more — there are many methods of food preservation around, and have been, for ages. But it wasn’t until we took a closer look at the atmosphere around products that we were really able to make a big difference. Altering this changed the game: it turns out it’s not that CO2 was deadly to the bacteria, but lack of oxygen is.

With that knowledge, more products, and in more stages of the supply chain can be protected. From vacuum packaging to controlled and even modified atmosphere: in this blog, we look at three main types of packaging techniques that take advantage of low oxygen levels.


MAP is based on the modification of the air inside the package. In a nutshell, it is displacing normal air for a composition of gases. It creates an atmosphere that is low in oxygen, often with altered levels of nitrogen or carbon dioxide. The composition can be entirely changed based on the product.

Getting this composition right has great benefits:

  • Extended shelf life
  • Pests and contamination don’t stand a chance
  • No use of chemicals: suitable for organic products
  • Quality control

The process of creating a modified atmosphere starts with creating a vacuum, but unlike with vacuum packaging, it is not the goal to merely rid all the air in the package. After creating a tight vacuum, a process of gas flushing starts. This means that nitrogen gas is actively pumped in to displace oxygen. Nitrogen is used as a displacement of oxygen to delay oxidation, slows down spoilage, and acts as a filler to maintain package conformity.




Modified Atmosphere Packaging can be divided into two different categories, active and passive.

Active Modified Atmosphere Packaging is defined as the displacement of gases in the package, which is then replaced by a desired mixture of gases.

Passive Modified Atmosphere Packaging is when the product is packaged with a certain film type and the desired atmosphere within the package develops naturally as a consequence of the products’ respiration and the diffusion of gases through the film.


CAP or CAS is a storage technique, rather than a shelf-ready retail tactic. It allows alterations to the storage conditions of the packaging during its lifespan. With Controlled Atmosphere, the gas composition isn’t modified straight away. But later on, using proper films or coatings, you are able to change the gas, reacting to the respiration inside the bag. Think of adding oxygen absorbers or nitrogen to achieve the optimal gas composition to extend shelf life and eliminate the growth of pests, bacteria and diseases.


Modified Atmosphere Packaging:

The gas composition is modified initially, creating a custom atmosphere for each product type

Controlled Atmosphere Storage:

The atmosphere is continuously controlled throughout the storage period


With airtight vacuum packing, (almost) all air is removed from the packaging. The packaging is then hermetically sealed to maintain the vacuum. This technique has several benefits:

  1. It protects the contents from oxidation/slows down the oxidation process
  2. It prevents the buildup of moisture
  3. It inhibits the growth of oxygen-dependent microorganisms and reproduction of insects

However, a certain amount of oxygen will always remain in the packaging, limiting the use of vacuum packaging to certain products.


One of the biggest benefits of MAP in combination with our FIBCs is that it can be applied to a wide range of products, from rice grains to mining and mineral. Additionally, it can be entirely altered to the specific needs of the product in the bag, taking into account the unique characteristics of every product. Want to know how it can benefit your supply chain? Contact us to find out more.


Want to work towards sustainable supply chain management?

At Masterpack, we are continuously working towards better ways to pack and protect products. We proudly present our newest solution: Modified Atmosphere for FIBC’s. Download our latest whitepapers:

Testing and improving your packaging (1,6MB)
Modified Atmosphere in FIBC's (6,4MB)
Pest prevention and control in bulk packaging (2,8MB)
The Modified Atmosphere Packaging Process Whitepaper

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