What is water activity?
Water activity is the
measurement of water vapor pressure generated by the free or
non-chemically bound water in foods and other products. The bound water
and moisture content cannot be measured directly with this method.
Aw value (range: 0.00...1.00 aw) is an important indicator for the
shelf life of foods, pharmaceutical and cosmetic products and it
strongly influences the occurrence and growth of micro-organisms. The
free water in a product influences its microbiological, chemical and
This is of great
importance especially for perishable products such as foods, grains,
seeds and particularly for pharmaceutical powders and tablets. If there
is too much free water, the food is spoiled. Too little water can
adversely affect product properties.
new station probe HC2-AW-USB offers new possibilities. The USB probe
can be directly connected to a PC running HW4-P-QUICK-Vx software
enabling water activity measurement capability. The HC2-AW-USB is the
perfect device for a multi station application, as multiple probes can
be attached to a single PC.
USB station probes
probes can be ordered as single probe or as a set including the HW4
software with Aw Quick function. The set offers all possibilities to
measure water activity.
- Complete set of probe and HW4 including Aw Quick function available
- Measurement range: 0.00…1.00 Aw (0…100 %RH), -40…85 °C (-40..185 °F)
- USB interface for direct connection to a PC (HC2-AW-USB)
insertion probe is suitable for measurement in dust-free bulk
materials, bricks, concrete, etc. It measures humidity and temperature
and calculates the dew/frost point.
Water activity measurement, mobile measuring units with handheld instruments and data loggers
- Range of application: -40…85 °C / 0…100 %rh
- Digital interface (UART) and scalable analog outputs, 0…1 V
- Standard output scaling: 0…1 V = -40…60 °C / 0…100 %rh
- Adjusted at 23 °C and 10, 35, 80 %rh
provides a high-end laboratory device – the HygroLab C1 – for water
activity measurements with up to four probes. Connect station probes and
insertion probes for measuring water activity in cheese, meat, tobacco,
building materials, animal feed, pharmaceuticals products and much
and intuitive, the laboratory grade indicator can be used by anyone.
HW4 running on a PC provides remote monitoring with charting and data
input channels for HC2 station probes or HC2 insertion probes can be
connected for measurement of water activity, relative humidity and
- Aw Quick function for fast measurement results (typically 4-5 minutes)
- Audible alarm to indicate completed measurement
- Saves up to 2,000 data records with %RH, °C/°F, date and time