Can I eat food that might be spoiled if it smells okay?

This week's entries are brought to you courtesy of my brother who, as of today, is still living without power after severe storms passed through Southern Illinois several days ago. He and his wife came up to stay with us in the St.Louis area (just about 90 miles away) so they could enjoy the luxuries of hot showers, lights, internet access, and food that wasn't spoiled!
They had to return to their home before power was restored in order to get grades turned in for the semester end at Southern Illinois University where he is a professor. So after a lovely visit and some shared meals, we set about figuring out what they could bring home that would be safe to eat: without refrigeration, without electricity to heat a microwave dinner, or a freezer in which to keep any frozen; and without potable water (although they did purchase a portable camp stove so they could boil water and also cook in a pinch).
For now here are some facts on food safety, and tomorrow I'll bring you some ideas for what you can eat when you have no electricity. My brother had a great idea--he recommends you print this out now, while you have power for your printer and your computer, and while you have internet access. If you need this information when the power is out, you won't be able to access it!!
When Is Food Safe to Eat?
1) Never rely on smelling food to see if it's safe! Food does not always smell bad when it is teeming with bacteria. Yes, if it does smell funny you should throw it out. But just because it smells okay and looks okay, that doesn't mean you won't get food poisoning: There are more reliable ways to tell if it is safe!
2) Check the Temperature: Food has to remain within certain temperature zones to minimize replication of bacteria that are present. The so called "danger zone" (where you don't want the food to be) is between 40 and 140 degrees Fahrenheit; this is where bacteria multiply more quickly.
Notice that room temperature is in this danger zone, and so is picnic weather, and so is leaving it in your car while you do some more shopping and catch a movie! Food should be kept below 40 degrees Fahrenheit (which is the temperature in your refrigerator) or above 140 degrees (which happens when you cook it to the proper temperature and keep it warm until the guests arrive).
Your refrigerator should probably be at 36 to 38 degrees in order to be sure the food contained is all below 40 degrees. Keep a food thermometer on the top shelf or in the door to monitor this. After a power outage the foods in the fridge along with the insulation will keep it cool enough for several hours--maybe even overnight. So if the power outage is brief (say, six hours) you can check your trusty thermometer for assurance and as long as the temperature hasn't exceeded 40 degrees, you can keep all your food for safe consumption.

3) The Test of Time: Sometimes food will come into the danger zone and that's perfectly fine for a short period of time. For instance, while you are eating dinner, if you notice, as you reach for a second helping of meatloaf and mashed potatoes 15 minutes after it was set on the table, the food is not steaming hot. Testing the temperature with a food thermometer will show you that it has fallen below 140 degrees and is now in the "danger zone". But it does take time for the bacteria to multiply--you won't get food poisoning from food the instant it falls into this temperature range.

The safe guideline is to get food back to below 40 or above 140 degrees within two hours. So it's perfectly okay to have a leisurely dinner and put the leftovers back into the refrigerator 45 or even 90 minutes later.

This is why a brief power lapse will not affect the safety of refrigerated food. A four hour outage is no reason to dump all the contents of your refrigerator: It takes a while for the temperature to rise when everything inside is cooled. Certainly, though, after 24 hours or more the temperature is likely to have risen above 40 degrees inside the appliance, and the food will likely be creeping up into the danger zone. Having a thermometer in the refrigerator will be most helpful to determine at what point it's time to throw out the refrigerated foods.

Once power is restored to your neighborhood and your refrigerator is humming along, realize that it may take several hours (probably at least 12) for it to actually cool back down to below 40 degrees. Do not stock the refrigerator until the internal temperature is back in the safe zone. Use your thermometer to show you when you can safely purchase more milk, meat, spreads and sauces, and other perishables . . or you will have another load of spoiled food on your hands.
4) When in Doubt, Throw it Out! If you aren't sure about the safety of a food as a result of power outage, a questionable thermometer, or leftovers inadvertently left out for too long, just throw the food away. It's a shame to waste food, but it's even worse to make someone ill over eating something you aren't certain is safe. Food poisoning is uncomfortable at best, and can even be fatal in small children, older adults, and people with compromised immune systems.
So there you have it: after a power outage, mind the time that perishable food stays within the safe range below 40 degrees; take your time re-stocking the refrigerator when power is restored; and just toss anything that gets up to room temperature for more than a few hours. Be safe!