ISO 9622:1999 PDF

Scope: This International Standard describes the operating conditions for instruments used for the determination of fat, protein and lactose content of ex-farm milk, based upon the measurement of the absorption of mid-infrared radiation at wavelengths which are representative of each component analysed. NOTE 1 In practice, these measurements are made using commercial automatic or semi-automatic instruments defined in clause 5 and called "infrared instruments" in this International Standard. Any model of instrument which does not comply with the principle of analysis given in this International Standard or which incorporates modifications that may alter the principal characteristics of the apparatus (repeatability, accuracy, conditions of use), as well as the means of adjusting the calibration, will require a separate specific standard. NOTE 2 Not all instruments allow determination of the lactose content. Moreover, some instruments allow direct measurement of the water content. The total solids content can be estimated by adding together the fat, protein and lactose contents, a constant being used to correct for the salt content. The method described is applicable to the determination of the fat, protein and, as appropriate, lactose content of ex-farm milk. The method is also applicable to the analysis of milk of other species (goat, ewe, buffalo, etc.) and processed milk provided a specific calibration of the instrument (see clause 7) is made.

ISO 9622:1999 Referenced Document

ISO 1211 Milk — Determination of fat content — Gravimetric method (Reference method)*， 2010-06-01 Update
ISO 5765-1 Dried milk, dried ice-mixes and processed cheese — Determination of lactose content — Part 1: Enzymatic method utilizing the glucose moiety of the lactose*， 2002-09-01 Update
ISO 5765-2 Dried milk, dried ice-mixes and processed cheese — Determination of lactose content — Part 2: Enzymatic method utilizing the galactose moiety of the lactose*， 2002-09-01 Update
ISO 8968-1 Milk and milk products — Determination of nitrogen content — Part 1: Kjeldahl principle and crude protein calculation*， 2014-02-01 Update
ISO 8968-2 Determination of milk nitrogen content Part 2: Batch dissolution method (macroscopic method)*， 2024-04-17 Update
ISO 8968-4 Milk and milk products — Determination of nitrogen content — Part 4: Determination of protein and non-protein nitrogen content and true protein content calculation (Reference method)*， 2016-04-01 Update
ISO 8968-5 Determination of milk nitrogen content Part 5: Determination of protein nitrogen content*， 2024-04-17 Update

2013 ISO 9622:2013 Milk and liquid milk products.Guidelines for the application of mid-infrared spectrometry
1999 ISO 9622:1999 Whole milk - Determination of milkfat, protein and lactose content - Guidance on the operation of mid-infrared instruments