INTERNATIONAL FOOD SAFETY CONSULTANCY
DR WILLEM MARSMAN
Refrigerators should stay at 41 degrees F (5 degrees C) or less. A temperature of 41 degrees F (5 degrees C) or less is important because it slows the growth of most bacteria. The temperature won't kill the bacteria, but it will keep them from multiplying, and the fewer there are, the less likely you are to get sick form them.
Freezing at zero degree F (minus 18 degree C) or less stops bacterial growth (although it won't kill all bacteria already present).
Hot foods should be refrigerated as soon as possible within two hours after cooking. But don't keep the food if it's been standing out for more than two hours. Don't taste test it, either. Even a small amount of contaminated food can cause illness.
Date leftovers so they can be used within a safe time. Generally, they remain safe when refrigerated for three to five days. If in doubt, throw it out, "It's not worth a foodborne illness for the small amount of food usually involved.”