Gas Mixture Guidelines for Food Products

Bridge Analyzers provide the reliable testing you need to ensure your gas flushed food product is successfully being packaged in the correct atmosphere for increased shelf life and to maintain quality.

Gas flushing is a type of modified atmosphere packaging (MAP). This process involves displacing the air with a controlled, desired mixture of gases. The gases used are typically oxygen, carbon dioxide, and nitrogen:

CO2 is the most important gas in the MAP of foods because it inhibits bacteria and fungi from reproducing.

O2 promotes several types of reactions in foods including fat oxidation, browning reactions, and pigment oxidation which lower quality and appearance.  Most of the common spoilage bacteria and fungi require O2 for growth. For these reasons O2 is either excluded or reduced to as low a concentration as possible in packaging. Exceptions occur where it is needed for the respiration of fruits and vegetables or the retention of color in meat. Myoglobin (the protein responsible for meat color) is what requires high oxygen levels. Highly pigmented meats like beef require higher oxygen concentrations than meats with low pigmentation levels such as pork.

N2 is an inert gas with no odor or taste. It has a lower density than air and low solubility in water and other food components. This makes it a useful filler gas in MAP to counteract package collapse caused by CO2 dissolving in the food.

The chart below provides MAP guidelines for retail packaging of gas flushed foods.