Determination of the water activity of some hygroscopic food materials by a dew‐point method

Abstract

Abstract A dew‐point apparatus for the determination of the water activity of stored foods and other substances is described and its precision assessed. The results of measurements at two temperatures and over a range of moisture content on a number of varieties of foods are presented; they are discussed in relation to the phenomenon of hysteresis and used to test two published equations relating water activity to moisture content and temperature.