We use to sell 25kg sacks of milk powder and each one used to pass over a check weighter before being palletised. We've also despatched powder in the tanker load and this is usually weighted. We are now supplied with ingredients in 25kg boxes or bags, and each of these has a decleration of weight on them.
Also with IBC or pallecons, they are usually individually weighted, and the weight usually attached.
Milk is usually weighted in a tanker, however the milk collected at the farm is measured in litres as there are flow meters attached to the tankers and this needs to tally with the BCT55 / weightbridge ticket.
Caz