Rotronic AwTherm water activity meter

Rotronic AwTherm water activity meter

Rotronic Logo

Products & Services | Rotronic AG


Rotronic’s AwTherm water meter offers a professional-standard, high-end laboratory unit than can provide temperature-stabilized measurement of water activity in foodstuffs, cosmetics and pharmaceutical products.

AwTherm is a stand along desktop device. Placing a sample under the closable reader will provide a highly accurate reading of free water, acting as a valuable guide to its microbiological, chemical and enzymatic stability.

Measuring water activity also provides useful information about characteristics such as cohesion, storage life, clotting or pourability of powders, tablets, etc., or the adhesive properties of coatings.


The Rotronic AwTherm meter offers a wide control range that permits measurements to be integrated directly in the tempered manufacturing or storage process. Water activity measurement reacts very sensitively to variances in temperature. Stabilizing the temperature prevents imprecise results due to external temperature influences.

The unit features a removable and exchangeable measuring head, allowing the Rotronic HYGROMER® IN-1 probe to be temperature-calibrated or adjusted for ultra-high precision.

For ultimate ease of operation, the AwTherm can be used in stand alone ‘island’ mode. For even greater precision, plus data logging, the unit can be Ethernet or MODBUS TCP/RTU connected to a PC to run in conjunction with ROTRONIC HW4 laboratory software.

The precise water activity (Aw) reading can indicate presence of bacteria, yeasts or mildew, as per the table below:

Water activity Contaminants
aw 0.91-0.95 Various bacteria
aw > 0.88 Various yeasts
aw > 0.80 Various mildews
aw > 0.75 Halophile bacteria
aw > 0.70 Osmiophile yeasts
aw > 0.65 Xerophile mildew



Other features include:

  • Reference Probe: ROTRONIC HYGROMER® IN-1, exchangeable for calibration or cleaning
  • Highest precision through exact stabilization of temperature
  • Wide temperature-control range
  • Excellent reproducibility
  • Excellent long-term stability
  • Variable size of sample container
  • Quickest measurements with the AwQuick function
  • Simple operation via Touch Interface
  • Conforms to ISO 21807 / EMC 2008/108/EC / IEC EN 61010-1:2010


Click on Rotronic AwTherm water activity meter for more information.
Click on Rotronic to contact the company directly.
Click on Products for more information on Rotronic measurement solutions.

Supplier Information
Supplier: Rotronic AG
Address: Grindelstrasse 6, CH-8303 Bassersdorf, Switzerland
Tel: +41 44 838 1144
Fax: +41 44 838 1487

Comments are closed.