A packaging gas is used to pack sensitive materials such as food into a modified atmosphere environment.
The gas used is usually inert, or of a nature that protects the integrity of the packaged goods, inhibiting unwanted chemical reactions such as food spoilage or oxidation.
Some may also serve as a propellant for aerosol sprays like cans of whipped cream.
[2] These gas types do not cause a chemical change to the substance that they protect.
Hydrocarbon gases approved for use with food need to be used with extreme caution as they are highly combustible, when combined with oxygen they burn very rapidly and may cause explosions in confined spaces.