Food & Pharmaceuticals

Aqualab TDL - Tunable Diode Laser Water Activity Meter

Measure the water activity of any sample with the first water activity sensor completely unaffected by volatiles. Anyone, from a technician in the lab to an operator at the line, can measure water activity in 5 minutes or less to 0.005 aw

How It Works

Put a 7.5 ml product sample in a disposable cup, seal the sample chamber lid over the sample, and wait for vapour equilibrium. At equilibrium, the relative humidity of the air in the sample chamber is equal to the water activity of the sample.

  • Fast - water activity readings in about 2 minutes
  • Accurate:  ±0.005 aw
  • Accurately read any sample, including those with volatiles
  • Verifiable with independent salt standards
  • Repeatable - different users, different locations, same result
  • Portable - weighs just 7 pounds
  • Easy to use - precise aw readings with minimal training
  • Secure - offers administrative control over calibration and data

Tunable Diode Laser Sensor

The Aqualab TDL's sensor measures the relative humidity of the air in the sample chamber by emitting a finely-tuned infrared laser beam across the headspace above the sample. Because water vapour has strong absorption bands in the near infrared (NIR), the sensor can measure the presence of water vapour in the headspace very precisely.

Unaffected by Volatiles

The beam of the laser, which is less than one nanometer wide, is specific for the commonly occurring isotope of water. Other vapour molecules, even those from different isotopes of water do not affect the reading.

Read Any Sample

The sensor is powerful enough to measure the water activity of previously impossible to measure samples, including soy sauce, ethanol and even gasoline.

Secure Data

AquaLab TDL stores time, date and user information with every measurement and calibration and can store up to 8,000 secure data points. Set up to 25 unique users and passwords to control access to data.
Use AquaLink software to maintain compliance records and archives, do statistical analysis and print reports for customers and decision-makers.

Measurement Range Water Activity 0.030 to 1.000
Resolution +/- 0.0001
Accuracy +/- 0.005
Sample Time Less than 5 Mins
Sample Size Up to 14 ml
Sample Type Powder, Liquid or Solid
Sample Temperature Control 15°C to 50 °C +/- 0.2°C
Output Download direct to PC
Input Mains 110/240 VAC
Sensor Type Tunable Diode Laser
Warranty 1 year parts and labour

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Robust, Easy to Clean

The sensor has no moving parts, and is housed in fully-sealed sample chamber. The clamshell lid offers easy access to all parts of the sample chamber for cleaning.

Use (Almost) Anywhere

Water activity is temperature dependent. Internal temperature control lets you set a measuring temperature between 15° and 50° and use the instrument anywhere, even outside a climate-controlled facility.

Use the Aqualab TDL to get lab-quality water activity measurements at the line, receiving dock, processing plant, storage facility-anywhere you need to test and verify the safety and quality of your products and ingredients.

TDL Leaflet
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Aqualab Catalogue
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Water Activity Chart
Size: 1.0 MB (1,081,938 bytes)

Quotation Request

Email us to request a quotation for the Aqualab TDL