Saturday, May 12, 2007
5 Second Rule
May 9, 2007, NYT
The Curious Cook
The Five-Second Rule Explored, or How Dirty Is That Bologna?
By HAROLD McGEE
A COUPLE of weeks ago I saw a new scientific paper from Clemson University that struck me as both pioneering and hilarious.
Accompanied by six graphs, two tables and equations whose terms include “bologna” and “carpet,” it’s a thorough microbiological study of the five-second rule: the idea that if you pick up a dropped piece of food before you can count to five, it’s O.K. to eat it.
I first heard about the rule from my then-young children and thought it was just a way of having fun at snack time and lunch. My daughter now tells me that fun was part of it, but they knew they were playing with “germs.”
We’re reminded about germs on food whenever there’s an outbreak of E. coli or salmonella, and whenever we read the labels on packages of uncooked meat. But we don’t have much occasion to think about the everyday practice of retrieving and eating dropped pieces of food.
Microbes are everywhere around us, not just on floors. They thrive in wet kitchen sponges and end up on freshly wiped countertops.
As I write this column, on an airplane, I realize that I have removed a chicken sandwich from its protective plastic sleeve and put it down repeatedly on the sleeve’s outer surface, which was meant to protect the sandwich by blocking microbes. What’s on the outer surface? Without the five-second rule on my mind I wouldn’t have thought to wonder.
I learned from the Clemson study that the true pioneer of five-second research was Jillian Clarke, a high-school intern at the University of Illinois in 2003. Ms. Clarke conducted a survey and found that slightly more than half of the men and 70 percent of the women knew of the five-second rule, and many said they followed it.
She did an experiment by contaminating ceramic tiles with E. coli, placing gummy bears and cookies on the tiles for the statutory five seconds, and then analyzing the foods. They had become contaminated with bacteria.
For performing this first test of the five-second rule, Ms. Clarke was recognized by the Annals of Improbable Research with the 2004 Ig Nobel Prize in public health.
It’s not surprising that food dropped onto bacteria would collect some bacteria. But how many? Does it collect more as the seconds tick by? Enough to make you sick?
Prof. Paul L. Dawson and his colleagues at Clemson have now put some numbers on floor-to-food contamination.
(Here is the link to the article, in the J of AM. All part of the service, here at the End)
(Nod to Anonyman, who counts to five very slowly. I've seen him.)