Let’s face it: we’ve all dropped a piece of food on the floor and uttered the ’5-second rule’ expression. But considering that 1 in 6 people suffer from a foodborne illness every year is it really okay to do so? Can harmful microbes really leap off the floor onto the food in only a matter of seconds? Scientists at Rutgers University put the colloquialism to the test.
In their research published in the medical journal Applied and Environmental Microbiology, the scientists led by Professor Donald Schaffner assessed the validity of the expression, citing concerns of the widespread nature of the practice as the rationale behind their review. They assessed whether harmful bacteria could transfer from the floor to the food within only 5 seconds or less. They used 4 different surfaces: wood, stainless steel, ceramic tile and carpet contaminated with a type of bacteria known asEnterobacter aerogenes, which is a cousin of Salmonella.
They tested four different foods on each of the surfaces: watermelon, bread, bread with butter and gummy candies. Then they assessed four different contact times: 1 second, 5 seconds, 30 seconds and 300 seconds. So what did they find? Drumroll please.
Photo by Wimena Kane