Division 4.2.2.1 Mix the milk by an appropriate procedure, before sampling.

To mix the contents of large vessels or of storage, rail or road tanks, the use of mechanical agitation is advised (4.2.2.2.).

The extent of mixing shall be appropriate to the period of time over which the milk has been at rest. The efficiency of the procedure of mixing applied in any particular circumstances shall be demonstrated as being adequate for the purposes of the analysis envisaged; the criterion of mixing efficiency particularly influences the similarity between analytical results from samples taken either from different parts of the consignments, or from the outlet of the tank at intervals during discharge. A procedure of mixing milk (untreated milk or whole milk) shall be considered efficient if the difference in fat content between two samples, taken under these conditions, is less than 0,1 %.

In a large vessel with a bottom discharge outlet there may be, at the discharge point, a small quantity of milk which is not representative of the whole contents even after mixing. Therefore samples should preferably be taken through a manhole. If samples are taken from the discharge outlet, run off sufficient milk to ensure that the samples are representative of the whole.