7. Glossary

Activité de l'eau; water activity A _w

Can be defined as the ratio of water vapor pressure in an environment in thermodynamic equilibrium with a substance containing water to that which would prevail under the same conditions with pure water. In this way, dehydration of a product (drying) enables this activity to be lowered below a certain threshold, so that the humidity of the environment in equilibrium with the product in its vicinity remains below a level favorable to the development of micro-organisms.

Modified atmosphere packaging (MAP)

Modified atmosphere packaging (or protective atmosphere packaging) involves modifying the composition of the internal atmosphere of a package (usually foodstuffs) in order to improve its shelf life. The process generally involves replacing oxygen with...