Raw milk contain lots of bacteria that are not good for human health and they should be killed before we drink milk. Pasteurization of milk is the process which makes the raw milk drinkable.
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There are different ways to pasteurize milk some of them are efficient which can make milk almost free from bacteria. To Pasteurize milk you need a pot or a double boiler and regular milk filter. Temperature is very important so for exact measurement of temperature you need a thermometer and then to cool down milk quickly you need some ice.
To start the process you need to filter the milk with the help of regular milk filter so that solid particle does not remain in the milk. After that take water in a larger pot and boil it and put the container of the milk in larger pot. Put thermometer in it so that you can measure the temperature. Heat milk for 165 degrees until 15 seconds or 164 degrees for 15 seconds.