Doctor double dip

Log cfu/ml of bacteria recovered from sterile water in which crackers had been dipped 3 or 6 times, discarded after each dip, with or without being bitten before dipping. Credit: Data courtesy of Paul Dawson" />Log cfu/ml of bacteria recovered from sterile water in which crackers had been dipped 3 or 6 times, discarded after each dip, with or without being bitten before dipping. Credit: Data courtesy of Paul Dawson Who hasn't in

Written byMargaret Guthrie
| 3 min read

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Who hasn't invoked the five second rule? After all, food that falls to the kitchen floor is still safe to eat, if you pick it up fast enough. Isn't it?

Paul Dawson, of Clemson University's food science program, roots out the science behind such questions and in doing so has found a way to engage undergraduate students, teach them the rigors of scientific investigation, and even encourage some to seek advanced degrees in the sciences. His formula is simple: Test the logic - or lack thereof - behind pop culture myths or stories. He started with the five second rule: if you drop a piece of food on the floor then pick it up in less than five seconds, it's safe to eat. Dawson's study set the popular wisdom on its ear. No matter how quickly the dropped morsel is retrieved, it's crawling with all kinds of bacteria.

After debunking ...

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