The following articles are necessary for the pasteurization of milk: Pail or deep kettle, rack such as is placed under meats in cooking, or a perforated pie tin, dairy thermometer.
Place the rack or an inverted perforated pie tin in the bottom of the pail. Arrange the bottles of milk on the rack. Do not remove the caps from the bottles. With a towel wrung out of hot water cleanse the caps and mouths of the bottles. Make an opening in the cap of one of them large enough to insert a thermometer. Surround the bottles with cold water. Fill the pail sufficiently full that the water will entirely surround the milk. Place the pail containing the bottles over the fire and bring quickly to a temperature of 145° to 150° F. as is indicated by the thermometer within the bottle of milk. As soon as this temperature is reached, remove the bottles to a table or shelf out of a draft, cover with a towel and let stand 10 to 20 minutes. Then cool by placing in warm water and gradually replacing with cold water. Set on ice and do not remove the caps until the milk is needed.
The word sterilized is really a misnomer in this recipe, as the process is one of pasteurization rather than of sterilization.
Use only sweet cream. Pasteurize it the same as for pasteurized milk. It may be more convenient to use a double boiler for this purpose. If so, bring the cream to a temperature of 145° to 150°, and proceed the same as for pasteurization of milk. Cool the cream to about 50°. Churn the cream, keeping it at as nearly 50° as possible. Collect the butter and work with a paddle, scalded and then chilled, and press into a mold or a roll. Sweet butter is usually served without salt, though if preferred some salt may be used.
Heat sour milk very slowly until the whey rises to the top; pour it off, put the curd into a bag and let it drip for six hours without squeezing it. Put it into a bowl and break it fine with a wooden spoon. Season with salt and mix into a paste with a little cream or butter. Mold into balls and keep in- a cold place. It is best when fresh.
Cut a pound of butter into 32 one-half ounce squares.
Scald and soften the butter paddles with hot water. Scrub with brush and hot soap suds and chill in cold or ice water. Roll the butter between the paddles to form the balls.