Who has never picked up food that has fallen on the floor (a crisp, a lettuce leaf, etc.), blown on it and eaten it? A study conducted at Rutgers University in the United States, and published in the journal Applied and Environmental Microbiology , may well put an end to a popular belief:the 5-second rule. According to her, it was possible to eat food that had fallen to the ground as long as it had not been in contact with the ground for more than 5 seconds. Well… that would actually be enough for it to get contaminated with the bacteria. Fine, then!
The researchers tested four different surfaces and four different foods:melon, bread, buttered bread and a gummy candy. They also experimented with four contact times:less than one second, five seconds, thirty seconds and three hundred seconds (five minutes). They then observed contamination by bacteria of the Enterobacter aerogenen type, close to salmonella. Verdict? The results indicate that it is the melon that becomes contaminated the fastest and the candy that resists the best. If the food is contaminated regardless of the time it remains on the ground, it should however be specified that the time of contact with the ground affects the quantity of bacteria transferred. Clearly:the 5-second rule is not totally wrong since the proliferation is less important if the food is very little in contact with the ground, but it will still be contaminated. Other studies have also proven that the type of floor has an impact on the proliferation of bacteria:for example, carpet is less conductive of bacteria than wood.
So if you're still tempted, it's better to opt for the candy combo on carpet than melon on parquet...
