MAP is a modern packaging technique that involves modifying the atmospheric composition within food and medicine packaging. This is typically done by manipulating the gases and packaging conditions, including the temperature and pressure within the packages, to increase the resistance of the enclosed products to decomposition and the incubation of aerobic organisms (germs).
CAS (Controlled Atmospheric Storage) has been used to provide food products for retail sale in foreign ports since the 1930s. Development began with the introduction of high levels of CO2 into cargo cells, especially on ships, and has since become MAP.
Modified atmosphere packaging (MAP) involves packaging food products in hermetic containers within controlled atmospheric environments, with the appropriate temperature, pressure and gas mixture. There are two main types of MAP packaging that are used for breathable and non-breathable products.
Types of food
MAP is generally used for food products that are raw or have undergone minimal processing before being packaged. Examples of these types of foods are processed fruits and vegetables, meats, seafood, bakery or dairy products, and cooked or cured meats.
MAP is beneficial especially in the case of meat products, as it often improves the shelf life to more than a week. Products that do not breathe are products that must be packed in hermetic and inert containers, so they are packed in high barrier material (low permeability to gas and humidity) with carbon dioxide or nitrogen.
Breathable products such as fruits and vegetables require interaction with the packaging material and therefore require packaging material with specifically adapted permeability to correlate with the respiration of the product, increasing freshness and therefore shelf life.