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Prairie Fare: Don’t Fall Prey to the 5-second Rule

If food falls on the floor, throw it out.

By Julie Garden-Robinson, Food and Nutrition Specialist

NDSU Extension

“Where’s that national award I won for you?” my daughter asked.

“My plaques are in the boxes in my closet,” I said.

I think I might wrap it and give her the plaque this year for her high school graduation. She and the rest of my family certainly have inspired me many times in the years I have written this column.

I should have guessed my daughter would go on to enjoy theater roles and comedy improvisation because of this award-winning “scene.” I’ve updated the food safety tips.

“Would you like pancakes today?” my then-4-year-old asked as I entered our living room.

“Sure, that would be nice,” I said. “What kind of toppings do you have?”

“Today we have blueberries, raspberries and strawberries,” she noted as she pointed to an imaginary menu on the wall.

“I’ll have two pancakes with blueberries,” I said.

“We’re all out of blueberries,” she announced.

“Okay, I’ll have raspberries,” I said.

“The raspberries fell on the floor,” she exclaimed, wrinkling her nose. “They’re dirty. Really, really dirty!”

“When was the last time this restaurant was inspected, anyway?” I asked.

“You can have strawberries,” she said, ignoring my question.

“They didn’t fall on the floor, did they?” I asked.

She grinned and left the room to get my food. I’d have to say those were the best imaginary pancakes and strawberries I ever had.

I was happy to hear that my young daughter had not fallen prey to the “five-second rule.” According to this often-quoted rule, you have a few seconds to pluck food from the floor before it becomes contaminated. Think again.

Several years ago, a high school student from Chicago put the rule to the test during an internship at an Illinois university. She surveyed people and learned that women were more likely to eat food that fell on the floor. She also learned that cookies and candy were more likely to be retrieved than vegetables. Imagine that.

She sterilized ceramic tiles, inoculated the tiles with E. coli bacteria and then dropped candy or cookies on the tiles. The bad news for food retrievers: Cookies and candy instantly picked up bacteria.

In another test of the famous rule, Clemson University researchers considered the bacteria-transferring properties of several types of flooring, including carpet, wood and tile. The materials were inoculated with salmonella and allowed to stand 24 hours to see if bacteria would survive. The carpet retained the most bacteria, but all the materials retained thousands of bacteria per square centimeter of flooring material.

The researchers dropped bologna and bread on the contaminated flooring material. Within five seconds, the food picked up thousands of bacteria.

Yes, the food that was on the floor longer picked up more bacteria, but don’t take that as evidence to retrieve your cookies, sandwiches or other foods. For some types of bacteria, only a few cells can make you sick.

As we’ve learned from spinach and lettuce foodborne illness outbreaks, washing doesn’t always get rid of pathogens (disease-causing organisms) on produce. The best advice: Don’t take chances. If you drop food on the floor, toss it in the trash.

Cross-contamination is the transfer of harmful bacteria from surfaces to food or from one food to another. Cross-contamination is one of the leading causes of foodborne illness in the U.S. Consider these tips from the U.S. Department of Agriculture:

  • Use hot, soapy water and paper towels or clean cloths to wipe up spills or kitchen surfaces. Sanitize kitchen surfaces with a solution of 1 tablespoon of chlorine bleach per gallon of water (less than 1 teaspoon per quart). Or use another cleaner according to the manufacturer’s directions. Test a spot before using a sanitizer.
  • Wash cloths in the hot cycle of your washing machine.
  • Use clean cutting boards. Use one cutting board for fresh produce and a separate one for raw meat.
  • Separate meat, poultry and seafood from other foods in your shopping cart and in your shopping bags. Whenever available, place meat packages in plastic bags before placing them in your cart.
  • Keep raw meat, poultry and seafood in containers or sealed plastic bags on the lowest shelf of your refrigerator to help prevent their juices from dripping on other foods.

Here’s a family-favorite pancake recipe to enjoy with strawberries, blueberries or raspberries. You will want to rinse the fruit under running water before serving. If they fall on the floor, you know what to do.

Buttermilk Pancakes

2 c. buttermilk (or substitute reconstituted dry buttermilk)
2 eggs, beaten
1 tsp. salt
1 tsp. baking soda
2 tsp. baking powder
2 Tbsp. sugar
1 3/4 c. all-purpose flour
1 1/2 Tbsp. butter or margarine, melted

Preheat griddle to 375 degrees. Mix buttermilk and eggs together. In separate bowl, stir dry ingredients together (or use a sifter). Stir in buttermilk and egg mixture. Add melted butter and mix. Drop from ladle onto hot griddle, cooking each side about two minutes or until light brown.

Makes four servings. Each serving has 360 calories, 10 grams (g) fat, 55 g carbohydrate and 20% of the daily recommendation for calcium.

(Julie Garden-Robinson, Ph.D., R.D., L.R.D., is a North Dakota State University Extension food and nutrition specialist and professor in the Department of Health, Nutrition and Exercise Sciences. Follow her on Twitter @jgardenrobinson)

NDSU Agriculture Communication - May 20, 2021

Source: Julie Garden-Robinson, 701-231-7187, julie.garden-robinson@ndsu.edu

Editor: Ellen Crawford, 701-231-5391, ellen.crawford@ndsu.edu



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