Replacing Total Moisture Measurements By Water Activity Determination

This short video explains the difference between total moisture content, headspace moisture, and the relation to water activity. The new USP <922> Water Activity chapter implemented this year, outlines the recommended methods to qualify, calibrate, and use water activity meters to accurately measure the water activity of raw materials and products. It describes laser-based headspace analysis as a non-invasive technique to measure water activity in sealed containers and the only method that can correctly measure water activity in the presence of other volatiles.