This refers to the practice of modifying the head space or air surrounding the food or beverage in the package. This technique is used to extend the shelf-life of food and beverages. Pharmaceuticals, cosmetics and art can also be preserved in this way.
The modification process often tries to lower the amount of oxygen (O2), moving it from 20.9% 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 or inhibit the growth of bacteria. Carbon monoxide can be used for preserving the red color of meat. The mixture of gases in the package depends on the type of product, packaging materials and storage temperature.
Re-balancing of gases inside the packaging is often done through the use of active techniques such as gas flushing and compensated vacuum or passively by designing “breathable” films known as equilibrium modified atmosphere packaging (EMAP).
In gas-flushing, the desired gas mixture is instilled in quantity in the packaging, pushing out the air, whereas in compensated vacuum the air is removed and the desired gas mixture is then instilled.
What gas mixture is best for your product?
For details of the recommended gas mix, temperatures, shelf life and typical spoilage info, consult the extensive MAP Gas Selector on the Air Products website.
How do Oxygen & Carbon Dioxide (Head Space) Gas Analysers work?
Gas analysers are used to ensure that the Modified Atmosphere within packages meet quality standards. Analysis focuses on O2 and sometimes also on CO2 measurements. Too much O2 can result in increased growth of undesirable micro-organisms.
Random MAP testing is usually done as part of a Quality Assurance Programme:
- Spot checks are performed on the line at pre-determined intervals.
- A thin needle pierces the package and a pump draws out a tiny sample into the analyser.
- The measurement is recorded and the data stored on the instrument and / or a computer.
It is good practice to ensure good quality MAP for products, as incorrect gas levels can cause product waste.
Specifications of Headspace Analysers:
Trackback from your site.