Batch pasteurization (VAT pasteurization)
All milk was initially processed using batch pasteurization. A batch pasteurizer consists of a temperature-controlled, closed vat. The milk is pumped into the vat, heated slowly to a minimum temperature of 145° Fahrenheit, held at that temperature for a minimum of 30 minutes, cooled, and then pumped out of the vat. This method is relatively rare today, and is used mainly by local and regional creameries. The milk in Kalona SuperNatural™ fluid milk, butter, kefir and cream top yogurt has been batch pasteurized.