Milk is collected from the farm every 24 or 48 hours. The tankers that are used have a special stainless steel body which are heavily insulated to keep the milk cold during transportation to the processing factory. Milk tanker drivers are accredited milk graders, which allows them to evaluate the milk prior to collection. Tanker drivers grade and if necessary reject milk based on temperature, sight and smell.  A representative sample is collected from each farm pickup prior to being pumped onto the tanker. After collection, milk is transported to factory sites and stored in refrigerated silos before being processing.