Dropped foods with high salt or sugar content may be safer to eat than other foods, study reports.
This finding has important implications for followers of the “3-Second Rule”, and was reported by researchers at Manchester Metropolitan University in England, on behalf of Vileda, a household products company.
Are you a proponent of the 5-second rule (or whatever time limit you choose to use)? There seem to be any number of variations on this rule, with the time limit often being modified based on how long it actually takes a person to retrieve their dropped food before the dog gets to it!
Call it what you like – superstition or conventional wisdom – this rule has certainly received some scholarly attention over the years, including this most recent study.
The researchers tested a variety of foods that are eaten commonly, and that contain different water activity levels – a major factor in determining whether food items will allow bacterial growth in just a few seconds.
Ham, cooked pasta, bread with jam, a plain cookie, and dried fruit were all dropped on the floor and then left for intervals of 3, 5, and 10 seconds. The foods were then evaluated to determine whether harmful bacteria found on the floor were then found on the dropped food.
They found that the level of water, salt, and sugar in a food type influenced how much bacteria it collected. Due to their low water content, cookies appeared to do best, and were relatively safe to eat after being on the floor for 3, 5, or 10 seconds. The salty ham and the sugary bread and jam seemed to do relatively well, showing little bacterial growth if they were removed from the floor within 3 seconds. But the cooked pasta and dried fruit showed growth of klebsiella after just 3 and 5 seconds respectively – a bacterial agent with the potential to cause a range of diseases such as urinary tract infection, pneumonia, and septicemia.
Overall this study showed that processed foods with their high sugar or salt content were less likely to allow harmful bacteria to survive on them, and may therefore present the least risk to health when eaten off the floor – maybe their only saving grace from a healthy eating standpoint!
But regardless of the results, it’s important to obviously remember that any dropped food becomes immediately contaminated, whatever its water, salt, and sugar content. So even though there may be degrees of contamination – when in doubt, throw it out!