The total moisture percentage includes both bound water and free water. The Aw value indicates the amount of free water in the moisture percentage. The proportion of free water determines whether microbiological growth is possible. This is why measuring the Aw value is so important.
Preventing microbiological growth
To prevent microbiological growth, you must keep the Aw value below 0.600 Aw. This can be done by binding the free water using salt, other binding agents or using methods such as smoking the product.
Aw value interesting in many sectors
You’ll understand that measuring the Aw value is important in the food industry. It is used to determine the shelf life of the product and, among other things, so you can prove your product has been kept below the listeria limit.
Measuring the Aw value is also essential in other sectors. For example, the pharmaceutical industry uses the Aw value to determine whether a tablet will disintegrate quickly. It is handy to know when the tablet releases its active ingredient. Seed improvement companies use the Aw value to monitor seed germination and the Aw value also plays a major role in the animal feed industry.