11. Glossary

Water activity (A _w )

Activity Water, hence the symbol A _w .

Represents the proportion of free water in a product. It is one of the main parameters influencing the preservation of food or pharmaceutical products. The greater the amount of free water (A _w high), the greater the potential for micro-organisms to thrive.

Calculated as the ratio between the water vapor pressure of a wet product and the saturation vapor pressure at the same temperature.

Appertisation

Heat treatment of a product to sterilize it.

Bag-in-Box ^®

Flexible packaging for liquids (wine,...