Rotronic redefines Water Activity measurement with HygroLab and technical briefing

white-paperRotronic AG
August 12th 2020

The measurement of water activity (aw) or equilibrium relative humidity (ERH) are key parameters in the quality control of moisture sensitive products and materials. Water activity is defined as the free or non-chemically bound water in foods, pharmaceutical, cosmetics and other products.

Rotronic, a world-leading manufacturer of measurement and monitoring equipment, has raised aw measurement to a new level with the release of HygroLab as an innovative high-end laboratory benchtop analyzer for water activity monitoring.

HygroLab allows simultaneous or asynchronous measurement using the tried-and-tested AW Quick measuring function within the HW operating system. Its modern and intuitive interface via touch screen allows standalone operation, while it can also be connected via internet for remote control via PC or tablet, allowing measurements to be thus be observed and reports downloaded remotely.

From concepts to technicalities

To accompany HygroLab, Rotronic has also prepared a technical white paper on the reliable measurement of aw and ERH in substances, including pharmaceutical products and fine chemicals.

The White Paper Water Activity downloadable from Rotronic AG (see Resources) covers all the key aspects of quantifying water activity.

After defining basic concepts such as ‘What is water activity’ the paper goes on to explain why it is important to measure it, the concepts of ‘water migration’ and ‘static equilibrium’ and real-world applications of aw measurement.

The paper also covers the technicalities of carrying out precise aw measurements, including calibration and adjustment, speeding up process and using Rotronic HW4 software to analyse results.


Click on HygroLab Laboratory Device for product information.
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