1. Milk is pumped directly from the milk can into the pasteurisation tank. The tank holds up to 20 gallons of milk.

2. The vat surrounding the pasteurisation tank is filled with hot water.

3. The tank and vat are turned on and heating begins.

4. An agitator attachment in the pasteurisation tank rotates during the heating process to ensure heat is distributed evenly through the milk.

5. An air space thermometer reads the milk temperature. When it reads between 140 and 143 degrees Fahrenheit, the tank heating is turned off.

6. A separate gauge reads the water temperature. It must be five degrees higher than the milk. Once the milk has reached between 140 and 143 the water temperature must correlate five degrees higher. If this does not happen naturally the temperature must be manipulated. Once the correct water temperature has been achieved, the vat heating is turned off.

7. While the heating is off, temperatures will continue to climb. When the milk reaches 147 degrees, water in the vat must be drained out.

8. The vat is immediately refilled with cool water and the temperature adjusted to chill the water further.

9. The milk is quickly cooled to 38 to 40 degrees. The agitator remains in, stirring the milk to ensure it is evenly cooled.

10. The milk is ready to be bottled.

The heating portion of the pasteurisation process takes between one and two hours depending on the quantity of milk being processed. The chilling process usually takes a further two hours.