Is It Possible to Pasteurize Milk at Home?

Yes, you can pasteurize milk at home and yes boiling and rapidly cooling can be used to pasteurize at home. It is unlikely that home pasteurization will be a perfect substitute for commercial pasteurization. However, it can be done and it will work. There are a few methods you can use. The last step is in any process you choose is always rapid cooling using ice-water.

The most practical method for pasteurizing milk at home for most people is probably the double-boiler method (i.e. water bath or bain marie). A double-boiler is a method of gently heating over steam. For this, you can use a dedicated double-boiler which consists of a pan inserted into another pan. You put some water in the bottom pan and the second pan sits up top without making contact the water. You heat the pan and the steam heats the food in the top pan. If you don’t have a double-boiler, you can use a large stainless steel bowl sitting on top of a large pan with water. This method is used for heating or keeping warm foods that require gentle heating like custards, Hollandaise sauce, chocolate, etc.

How to Pasteurize Milk Using a Double Boiler

Have a large pan of cold water ready to go.

1. Place milk in the top and water in the bottom of the double boiler.
2. Insert a candy thermometer into the milk and keep it there the whole time you are heating the milk. It’s best to use a metal thermometer because a glass thermometer could break.
3. Stirring constantly, gently heat the milk over the steam until it reaches a temperature of 161 F (71.7 C). Then, hold the milk at that at least 15 seconds.
4. It is important to stir constantly as this makes sure the heat is evenly distributed and all the milk is heated to the proper temperature.
5. After holding the milk at 161 F for 15 seconds, place the top pan or bowl into a pan of cold water and continue stirring the milk to help it all cool faster. Continue to monitor the temperature.
6. Once the milk temperature reaches below 130 F, replace the cold water with ice water and continue cooling the milk, still stirring, until the milk reaches 40 F (4.5 C) or below (fridge temperature).
7. Pour the cooled milk into clean containers, cover the containers, and store them in the refrigerator at 40 F or colder until used.

You can also use bottles or cans placed inside a canner, or an electric home pasteurization unit. A microwave oven can also be used. For more on home pasteurization of milk, see Food Preservation: Pasteurization of Raw Milk for Home Consumption by Ohio State University Extension.