Moisture Isotherm

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Price of the test:

$260 per analysis

Acceptable Matrices:

Moisture Isotherms can be performed on most food ingredients and finished products

Unacceptable Matrices:


Limit of Detection:


Sample Size Requirements:

125 grams


Salt Solution Chambers: (%RH) - 0,11,22,33,44,54,64,75, and 83

Reportable Units:

Graph depicting Equilibrium Moisture Content as a function of Relative Humidity

Turn Around Time:

20 Business days or until equilibrium is reached

Is Rush Available?


Method Reference:

Internally Developed Method

Method Description:

The lab weighs up a small amount of sample (as-is) and places it in one of nine jars. Each jar contains a salt solution which generates a specific relative humidity. The nine jars have the following % Relative Humidity (%RH) – 0/12/24/33/45/54/67/77 and 86. Intermediate points are difficult to obtain as there are not any safe salt solutions that represent such a RH. The sample is then left for anywhere from 3-6 weeks until it has equilibrated with the RH of the salt solution. Once it has equilibrated, the sample is evaluated for texture, appearance and any other pertinent physical characteristics at each of the 9 RH’s. The RH at which the sample is no longer acceptable is noted.

Additional Information:

The moisture isotherm data enables us to determine at what relative humidity (and moisture – critical moisture) your product will no longer be acceptable. In other words, it tells us the tolerance of a food product or ingredient.