International Standard
ISO 18787:2017
Foodstuffs — Determination of water activity
Reference number
ISO 18787:2017
Edition 1
International Standard
Read sample
ISO 18787:2017
Published (Edition 1, 2017)
This standard was last reviewed and confirmed in 2023. Therefore this version remains current.

ISO 18787:2017

ISO 18787:2017
CHF 63
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ISO 18787:2017 establishes basic principles and specifies requirements for the methods of determining water activity (aw) of food products for human consumption and animal feed within a measurement range of 0 to 1.

The measurement principles are based on the dew-point measurement or on the determination of the change in electrical conductivity of an electrolyte or in the permittivity of a polymer.

The method does not apply to products stored below their freezing point (equivalent to the temperature at which ice crystals appear in the product), neither to products corresponding to a water-in-fat emulsion, nor to crystal products such as sugars, salt or minerals.

For products containing volatile compounds, such as alcohols, specific equipment adaptations may be necessary to apply the method.

The results of the interlaboratory studies that were carried out are given in Annex B.

General information

  •  : Published
     : 2017-11
    : International Standard confirmed [90.93]
  •  : 1
     : 9
  • ISO/TC 34
  • RSS updates

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