Barrier Packaging

Topic: Modified Atmosphere

Definition: Practice of modifying the composition of the internal atmosphere of a package (commonly food packages, but this technique is also used for drugs) in order to improve the shelf life.

Modified Atmosphere Packaging(MAP):< is a technique used for prolonging the shelf-life period of fresh or minimally processed foods. In this preservation technique the air surrounding the food in the package is changed to another composition. This way the initial fresh state of the product may be prolonged. It is the shelf-life of perishable products like meat, fish, fruits and vegetables that will be prolonged with MAP since it slows the natural deterioration of the product. MAP is used with various types of products, where the mixture of gases In the package depends on the type of product, packaging materials and storage temperature. Meat and fish need very low gas permeability films so for non-respiring products (meat, fish, cheese etc.) high barrier films are used. The initial flushed gas-mixture will be maintained inside the MA package. But fruits and vegetables are respiring products where the interaction of the packaging material with the product is important. If the permeability (for O2 and CO2) of the packaging film is adapted to the products respiration, an equilibrium modified atmosphere will establish In the package and the shelf-life of the product will increase.
In the instance of bird seed and grain commodities, the use of Modified Atmosphere packaging also offers extended shelf life if unopened, freshness of the product and controls the enviroment to prevent insect infestation. Products found in this web site that are now MAP are Royal Cuisine, Natures Trail, Tail Royal Jubilee and now in Easy Pickens.

Process: The modification process often tries to lower the amount of oxygen (O2), moving it from 20% to 0%, In order to slow down the growth of aerobic organisms and the speed of oxidation reactions. The removed oxygen can be replaced with nitrogen (N2), commonly acknowledged as an inert gas, or carbon dioxide (CO2), which can lower the pH or inhibit the growth of bacteria. Carbon monoxide can be used for keeping the red color of meat.
Armstrong has been using carbon Dioxide (CO2) for the past 4 years in the Royal Cuisine and has resulted in excellent results for freshess as well as shelf life.

Technology: There are two techniques used in the industry to pack vegetables namely gas-flushing and compensated vacuum. For its cheapness the gas-flushing is more widely used. In gas-flushing the package is flushed with a desired gas mixture, as in compensated vacuum the air is removed totally and the desired gas mixture then inserted. The label “packaged in a protective atmosphere” can refer to either of these; an example of a gas mixture used for non-vegetable packaged food (such as crisps) is 99.9% nitrogen gas, which is inert at the temperatures and pressures the packaging is subjected to.
This technology is new to the birdseed packing industry. Armstrong Milling has chose to lead the industry using Gas Flushing technology to ensure its freshness as well as insect control.

Portions of this article was provided by “Wikipedia”. For More information visit: http://en.wikipedia.org/wiki/Modified_atmosphere - Modified_Atmosphere_Packaging_.28MAP.29