Why Does Milk Freeze in the Refrigerator?

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Milk is a dairy product and requires refrigeration at or below 40 degrees Fahrenheit. The colder milk is kept, the longer it will keep without spoiling. Milk freezes in the refrigerator when the temperature is set too low or the controls are malfunctioning.

Freezing Point of Milk

Unprocessed milk taken from a cow freezes at an average temperature of 31.091 degrees Fahrenheit. If the fat content or other components of the milk are reduced or water is added, the freezing point rises. Milk that freezes in a refrigerator is colder than 32 degrees.

Refrigerator Temperature

Refrigerators are designed to operate at temperatures between 33 and 40 degrees Fahrenheit. If the temperature rises above 40 degrees, foods like milk spoil faster. If the temperature falls below the freezing point of 32 degrees, milk and other foods begin to freeze.

Refrigerator Freezing

A refrigerator that freezes foods is allowing the temperature to drop below 32 degrees. Increasing the temperature control slightly may reduce freezing if the refrigerator is operating correctly. Some locations inside a refrigerator are colder than others. Moving the milk to a different location may stop it from freezing.

Temperature Check

Place a refrigerator thermometer inside the refrigerator during a period when the door will be closed for five to eight hours, such as overnight. Open the refrigerator and read the thermometer. If it is below 32 degrees, increase the temperature control setting. If you cannot adjust the temperature to keep milk from freezing, you may need to repair the temperature control and sensing unit.