In addition to keeping the temperature in your fridge at 40 °F, you can take additional steps to make sure your refrigerated foods stay as safe as possible.
Avoid "Overpacking." Cold air must circulate around refrigerated foods to keep them properly chilled.
Wipe Up Spills Immediately. In addition to helping reduce the growth of the Listeria bacteria (which can grow at refrigerated temperatures), getting rid of spills — especially drips from thawing meats — will help prevent "cross-contamination," where bacteria from one food spread to another.
Keep It Covered: Store refrigerated foods in covered containers or sealed storage bags, and check leftovers daily for spoilage.
Check Expiration Dates On Foods. If food is past its "use by" date, discard it. If you're not sure or if the food looks questionable, the simple rule is: "When in doubt, throw it out."
Clean The Fridge Out Frequently. Make this task part of your kitchen cleaning routine!