From:
http://www.ehow.com/list_6930222_correct-temperatures-refrigerators.html
Refrigerator Temperature
The FDA recommends keeping the refrigerator temperature at or below 40 degrees, which slows bacterial growth and maintains quality, according to the University of Nebraska extension service. A refrigeration repair website suggests 38 degrees as an optimum temperature. A unit set for 38 degrees can start cooling at that temperature and turn off at 35 degrees. Setting a temperature below 35 degrees requires a forced defrost cycle and uses additional energy.
Freezer Temperature
Keep the freezer at zero degrees, according to the FDA. The Nebraska extension service points out that zero degrees does not kill most bacteria, but it does stop bacterial growth. Flavor changes occur over time with frozen foods, and quality decreases the longer a product stays frozen.
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