1. Place bottles in vessel of warm water. Heat to 147° F. Keep at that
temperature thirty minutes. Take vessel off stove and cover with a
heavy blanket. Then pour off hot water and fill vessel with cold water
to cool the milk quickly.
2. Put milk in double boiler and raise to a temperature of 150° to 155°
F. Let stand at this temperature for twenty to thirty minutes.
Pasteurizing milk does not kill the ferments in the milk, but it kills
almost all bacteria except the spore-bearing bacteria, of which the gas
bacillus is the most important.