Eating on the floor – how long do germs really last?

Question every day

Damn: You just wanted to take a bite of the generously spread jam bread—and down the good piece. Where there used to be just plain flooring, you can now marvel at the colorful artwork.

No problem: It's been less than three seconds, so you can still eat it. Or maybe not?

The famous three-second rule

No doubt many people have heard of the three-second rule because it is now outdated and well-established. We know it from childhood, passed down through siblings or picked up in the schoolyard. The meaning is there Hand Floor: Dropped food remains edible as long as it remains there for less than three seconds.

The simple theory behind this is that with shorter contact with the floor, germs have less time to spread on the food. But as Jonathan Frakes put it on “X Factor”: Is this story true or completely fictional? Researchers have already gotten to the bottom of this question.

Eating on the floor – what does science say?

A research team at Rutgers University in New Jersey previously put the truth of this rule to the test in a study conducted in 2016 – albeit in this case under the name of the five-second rule, which has established itself as an alternative rule in some places. . The team, led by food science specialist Donald Schaffner, proceeded as follows:

Different foods were dropped on different floor surfaces. The food was bread, buttered bread, watermelon and fruit gum. Carpet, tile, wood and stainless steel that the products landed on were previously primed with salmonella-like bacteria.

Finally, the food was left on the floor for different periods of time — less than a second, five seconds, 30, and 300 seconds — and then examined for bacteria.

The three-second rule: what we know

The team came to the conclusion that several factors play a role, and yes, time matters too: after a few seconds, fewer bacteria were found in the food overall than after 30 seconds.

But more important is the question of whether the food is moist, like watermelon, or dry, like a slice of bread. Because: The more moist the food is, the more germs stick to it.

It has also been found that hard floors such as tiles transmit less bacteria than soft floors such as carpets. It is better to apply the three-second rule to a slice of bread that falls on a hard floor than to a piece of watermelon that lands on the carpet.

However, Schaffner of Rutgers University explains: “The rule is an oversimplification of what actually happens when bacteria move from a surface to food. “Bacteria can become contaminated immediately.” So, whether you assume three or five seconds: you can't be completely sure either way.