Depending on its use, in the USA much of the control is under the US Food and Drug Administration and here is one of their links: http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=184.1979c
By accessing the site I found other references that are also helping me. In the precinct of the National Archives there are references of standardized analytical methods for whey, which the codes are: 38235, 44024, 68120. These protocols are available?
Rodrigo, I believe the codes refer to official protocols published by AOAC International and referenced in US Government Documents. One can access AOAC International for a membership fee (expensive). You might wish to check with your library or your chemistry department do see if anyone is a member or has access. Many food processors also use the approved protocols because they comply with FDA requirements for import/export.