Quiz Yourself! Check Your Knowledge about Food Temperatures

Are the statements below fact or fiction?  Read them carefully and jot down your answers.  (Don’t cheat. Do this before you read the answers below.)  Then check your knowledge. If you answered most of the questions correctly, give yourself a pat on the back (which is challenging).  If you get several wrong, well, live and learn how to keep foods safe.

1. Raw meat can be marinated on the counter because bacteria can’t live in acidic marinades.  _____

2. It’s dangerous to heat up a cup of water in the microwave.  ______

3. If your turkey comes with a pop-up cooking timer, you don’t need to use a food thermometer to test for doneness. 

4. Adding salt to water for cooking pasta will speed up the cooking time. ______

5. Bacteria cannot grow in frozen food. ______

 6. On packaged frozen foods, the standing time (the length of time food should be held before consuming) is an optional instruction, given to keep people from handling the product while it’s very hot and could burn them.  ______

7. Your entrée cooked with alcohol can be consumed by a teetoler guest because all of the alcohol “burns off” during cooking.  ______

8. It’s a good idea to let hot leftovers cool for awhile before refrigerating them.  ______

9. Leftover cooked food should be reheated only once. ______

10. To avoid the risk of food-borne illness, cook chicken and ground beef to a higher temperature than fish or roasts.  _____

Okay, now you can read the answers:

1. Raw meat can be marinated on the counter because bacteria can’t live in acidic marinades.

Wrong.  FoodSafety.gov says the following: “Even in the presence of acidic marinade,  bacteria can grow very rapidly at room temperatures.”  Marinate perishables in the fridge.

2. It’s dangerous to heat up a cup of water in the microwave.

Believe it or not, this is a fact, and it can be a painful one to learn the hard way. The Tufts University Health and Nutrition Letter and many other sources have warned against mistakes that involve heating food either too little (not enough to kill pathogens) or too much (to cause “superheating.”)  The FDA has received reports of injuries due to superheating, which occurs when water is heated above the boiling point, and it then erupts when moved or stirred.   This risk is greatest with plain water in a clean cup, so add the teabag, instant coffee, or hot cocoa BEFORE you warm your beverage in the microwave.  For more information about microwave dangers, click on this link: http://shelflifeadvice.com/content/microwave-ovens-whats-safe-whats-not

3. If your turkey comes with a pop-up cooking timer, you don’t need to use a food thermometer to test for doneness. 

Get out that food thermometer.  These pop-up timers can’t be trusted because they are too short.  They don’t go deep enough into the turkey to tell you if it’s done in the middle.  According to Morton Satin, author of Food Alert!, they are accurate as far as they go, but, for a turkey weighing more than 10 pounds, they are not telling you when the whole turkey is safe to eat.  Also, recommendations are to test  the turkey for doneness in 3 places.  Obviously, one pop-up thermometer can’t do that.  For more information on checking a turkey for doneness, click here: http://shelflifeadvice.com/content/how-should-turkey-be-baked

4. Adding salt to water for cooking pasta will speed up the cooking time.

Wrong. Our authority is Robert Wolke, author of What Einstein Told His Cook (a classic book on kitchen science).  Adding salt may improve the flavor but, says Wolke, “Dissolving salt (or anything else…) in water will indeed make it boil at a higher temperature than 212ºF at sea level.  But, in cooking, the rise is nowhere near enough to make any difference, unless you throw in so much salt that you could use the water to melt ice on your driveway.” 

5. Bacteria cannot grow in frozen food.

True.   However, the important point to remember is that freezing food doesn’t kill bacteria either; it just keeps them from growing. When you defrost contaminated food, the bacteria will grow.  For the source of this statement, click here: http://shelflifeadvice.com/content/why-does-refrigeration-keep-bacteria-multiplying

 6. On packaged frozen foods, the standing time (the length of time food should be held before consuming) is an optional instruction, given to keep people from handling the product while it’s very hot and could burn them. 

Wrong. That may be an additional benefit to waiting, but it’s not the main reason for the statement. According to the FDA, the stand time is a required part of the cooking time.  Why? It allows time for the heat to reach the inner part of the product.  It’s a good idea to use a thermometer to tell if the internal part has reached the proper temperature (commonly165ºF).

7. An entrée cooked with alcohol can be consumed by a teetoler guest because all of the alcohol “burns off” during cooking. 

Wrong. Again, our authority is Robert Wolke, food science writer.  Here’s a summary of what he says: Many cookbooks say that the alcohol burns off, by which they mean it evaporates.  (It doesn’t burn off unless you light it.)  The “explanation” (which Wolke says is incorrect) is that alcohol boils at a lower temperature than water, so the alcohol will burn off before the water does.  BUT a mixture of alcohol and water will boil at a temperature somewhere between 173ºF and 212ºF (closer to 212ºF if it’s mostly water, closer to 173ºF if it’s mostly alcohol).  How much alcohol will remain in the food?  Experiments have shown it’s somewhere between 4%-49%.

8. It’s a good idea to let hot leftovers cool for awhile before refrigerating them.

Actually, this is a bad idea.  Because bacteria grow rapidly at room temperature, the goal is to get those leftovers below 40ºF as quickly as possible, certainly within 2 hours after cooking was completed.  If you don’t want to put very hot food in your refrigerator because you’re concerned about its effect on the other foods if the temperature rises in the fridge, here are two things you can do:

1) Put large amounts of hot food into 2 or 3 smaller, shallower containers and then on different shelves in your fridge. Smaller amounts of food will cool faster. OR 

2) Cool the food by setting its container in an ice bath.  For more information on handlng hot leftovers, click on this link: http://shelflifeadvice.com/content/should-hot-food-go-fridge

9. Leftover cooked food should be reheated only once.

That’s the advice of food scientist Susan Brewer.   Here’s her warning: “Every time food is heated, then cooled, then reheated, it goes through the “danger zone” (40F-140°F), the temperature range at which bacteria multiply quickly. Therefore, it’s best not to reheat the same food twice.” 

10. To avoid the risk of food-borne illness, poultry and ground beef must be cooked to a higher temperature than fish or roasts. 

That’s correct.  If you don’t have a chart that gives you the safe cooking temperatures for various foods, Shelf Life Advice has one.  Click here: http://shelflifeadvice.com/content/why-you-need-safe-cooking-temperature-chart-and-how-get-one-right-now  Read the article, and click on the link in line 4 to reach the chart.  Download it, print it, and post it on your fridge.

Sources: 

Wolke, Robert L., What Einstein Told His Cook, 2002.

Satin, Morton, Food Alert! 2008.

FoodSafety.gov “Food Safety Myths Exposed”

http://www.foodsafety.gov/keep/basics/myths/

FoodSafety.gov “Mythbusters: Learn the Truth about Food Safety in Your Home”
http://www.foodsafety.gov/blog/mythbusters.html

Environmental Nutrition (newsletter) “”8 Food Safety Myths Busted” August 2011. 

Susan Brewer, Ph.D., University of Illinois, Department of Food Science and Human Nutrition

Tufts University Health and Nutrition Letter, December, 2010, vol.28, number 10, “Ask Tufts Experts,” p.7.

(If you click on the links within the above article, you’ll find additional sources for the content in these answers.)