Do you know the “five second rule”? For many people, if food that has fallen to the floor is recovered in less than five seconds, it can be eaten normally.
But does this popular belief really work? Over the years, many researches have tried to prove this. Most of them concluded that the amount of bacteria transferred to food in contact with any surface depends not only on the time in which it was exposed, but primarily on the amount of microorganisms present.
For example, a loaf of bread that’s been left on your kitchen floor for five seconds is much less likely to get contaminated than if it’s dropped on a sidewalk on a busy city street. Provided, of course, that you keep your kitchen clean.
But, in addition, the type of surface can also affect pollution. Food that has fallen on carpeted areas, for example, is less contaminated than food that has been in contact with wood or tiled floors.
Study by University Clemson, in South Carolina (USA) found that less than 1% of bacteria that were on the carpet were transferred to the food. But when food came into contact with wood or laminate floors, between 48% and 70% of the bacteria were transferred.
Food on the ground: the level of contamination depends on the surface on which the food lands
Photo: iStock
But does the rule work or not?
Although the research gives us a certain advantage when considering the time, type of surface and food, from a food safety point of view, doctors do not recommend eating these foods.
The less time on the ground, the less chance of food contamination. But we cannot guarantee that a person will not develop an intestinal infection, for example, if he eats this food.
In principle, eating does not pose an imminent danger. The danger is that the bacteria that you swallow with food can multiply. and development inside our bodies and cause infection.
The risk of infection also depends on the type of bacteria present on the ground at the time of the fall. The most common viruses responsible for foodborne infections are rotavirus and norovirus. Among the bacteria are Salmonella, Shigella, Campylobacter.
Source: Cesar Barros, MD, an infectious disease doctor at the Emilio Ribas Institute of Infectious Diseases, in São Paulo; Tatiana tribesFood technician course coordinator Sinai Para sling
*With text from Cynthia Baio, in association with UOL
