I am copying information from a fact sheet available from Ohio State University Extension about meal moths. As you will see, it is possible to treat possibly infected foods in your freezer at the times listed below. Just putting them outside will not ensure that they would be consistently below 0°F. You could also be exposing the food to additional contaminates. It is not good for canned foods to be exposed to freezing temperatures.
The information referenced below also provides great information on cleaning to prevent re-contamination.
Let me know if you have additional questions.
[11/2/2010 9:53:39 AM]
3. Foods of questionable infestations or even lightly infested can be super-cooled or super-heated. Place exposed or suspect foods in a freezer at 0°F. for four to seven days or in a microwave oven for five
minutes or in a shallow pan or tray in the oven at 140°F for one hour or 120°F for two hours. Spread
the material thinly to permit effective cold or heat penetration to kill all life stages of the pest. If in
the oven, stir food periodically to prevent possible scorching. Dried fruits can be placed in cheese cloth
bags and dipped into boiling water for six to ten seconds to kill external pests. However, seeds saved
for planting may have the germination reduced after super-heating or cooling. Sifting the food material
will remove possible insect fragments and any remaining will not cause harm if consumed. After
insects are killed, contaminated food might be used outdoors during winter months for bird feed.