4TEV Water Activity Meter

Description

The AquaLab 4TEV Water Activity Meter is an analytical instrument designed to measure water activity (aw) in a wide variety of materials, from food products to pharmaceuticals and industrial materials. Its key feature is the inclusion of two distinct sensors: a standard dewpoint sensor for non-volatile samples and a dedicated volatiles capacitance sensor for samples containing compounds like ethanol or propylene glycol. Users can select the appropriate sensor via the instrument's menu. For measurement, a 7.5 ml sample is placed in a cup and sealed within the chamber. The dewpoint method, used for non-volatiles, employs an infrared beam to determine the dewpoint temperature of the sample vapor, translating it to a water activity value with an accuracy of ±0.003 aw. For volatile samples, the polymer-based sensor measures the equilibrium relative humidity in the sample headspace, with a stated accuracy of ±0.015 aw. The meter delivers readings typically within five minutes, offers verifiable calibration with independent salt standards, and is noted for its repeatability across different users and locations. It has a measuring range from 0.030 to 1.000 aw, weighs approximately 7 pounds for portability, and includes features for administrative data security. Its applications span baked goods, meats, cereals, nuts, spices, cosmetics, plastics, and tobacco.