By Toi Degree

Rowan Cooperative Extension

When was the last time you checked the temperature of your refrigerator or freezer? Have you ever?

If not you might want to do that. Did you know that the numbers used to adjust the temperature of most home refrigerators only raise or lower the temperature? They do not match specific temperatures.  Or that a different setting may be needed during the warmer months than colder months to maintain the same temperature?  Using a refrigerator/freezer thermometer is the only way to assure your refrigerator and freezer is at the correct temperature.

Refrigerator temperature
It should be 40 degrees or lower is the recommended refrigerator temperature to slow bacterial growth and maintain quality. Freezing occurs at 32 degrees; adjust refrigerator accordingly between 32 and 40 degrees to present unwanted freezing, such as freezing milk.

Freezer temperature
Zero degrees or lower is the recommended freezer temperature. At this temperature, bacterial growth will be stopped. However, freezing does not kill most bacteria, nor does it stop flavor changes that occur over time. Though food will be safe indefinitely at 0 degrees, quality will decrease the longer the food is in the freezer.
Freezing to 0 degrees inactivates any microbes — bacteria, yeasts and molds — present in food. Once thawed, however, these microbes can again become active, multiplying under the right conditions to levels that can lead to food borne illness. Since they will then grow at about the same rate as microorganisms on fresh food, you must handle thawed items as you would any perishable food.

In order to be sure that your refrigerator and freezer are kept at the correct temperature, buy thermometers to keep accurate readings.  Most refrigerator/freezer thermometers are either liquid-filled or bimetallic-coil thermometers.

The United States Department of Agriculture describes these thermometers as follows:
Liquid-filled thermometers are the oldest types of thermometers used in home kitchens. As the temperature increases, the colored liquid (usually an alcohol solution) inside the thermometer expands and rises to indicate the temperature on a scale.

Bimetallic-coil thermometers contain a coil made of two different metals with different rates of expansion that are bonded together. The bimetal element is coiled, fixed at one end, and attached to a pointer stem at the other end. As the temperature increases, the pointer will be rotated by the coiled bimetal element to indicate the temperature.

Buy refrigerator/freezer thermometers in the housewares section of department, appliance, culinary and grocery stores. Buy two. Place one in your refrigerator and one in your freezer. It may be the best $10 to $20 investment you ever make.

Two more tips:
·         Place the thermometer in the front of the refrigerator/freezer in an easy-to-read location.
·         Check temperature regularly — at least once a week.

Note: If the freezer compartment isn’t a separate freezer compartment, but a compartment inside the refrigerator, it may be impossible to obtain a 0 degree temperature. One sign of this will be soft ice cream. Plan to use food within a few weeks.

Information adapted from: Cook it Quick August Newsletter. Recommended Refrigerator and Freezer Temperatures, by Alice Henneman, MS, RDN, Nebraska Extension in Lancaster County
, Joyce Jensen, REHS, CFSP, Lincoln-Lancaster County Health Department.
For more information, contact Toi N. Degree, Family & Consumer Education Agent, at the Rowan County Cooperative Extension office, 704-216-8970, or email toi_degree@ncsu.edu