Test Price:
$46 per analysis
Acceptable Matrices:
Nearly all foods and food products
Unacceptable Matrices:
Samples containing high levels of propylene glycol
Detection Limit:
0.250 aw units (lower limit)
Sample Size Requirements:
10 grams
Equipment:
Water Activity Meter
Reportable Units:
aw Units
Water activity (aw) is the ratio of the vapor pressure of the water in the sample to the vapor pressure of pure water at the same temperature.
Turnaround Time:
7-9 business days
Is rush testing available?
Yes
Method Reference:
AOAC 978.18
Method Description:
This method is a measurement relating to the free, unbound water present in food and food products.
The atmosphere of a special sampling cell is evacuated, repressurized, and measured manometrically. The results are correlated to water activity in the sample.
Additional Information:
Water activity has little, if any, relationship to the total moisture content of the food. Water activity does provide a means of assessing the storability and bacterial susceptibility of shelf-stable foods. It is known that microorganisms cannot survive below certain aw levels, depending on the type of microorganism with botuli at <0.93; bacteria at <0.86; yeast cells at <0.78, and mold spores at <0.65.
Contact Us:
If you have questions about our testing services, please contact us at +1 (800) 245-5615.