How to Clean a Rough Kitchen Sponge Properly
You use a kitchen sponge to wipe the roughest objects in the sink, so it makes sense that a fairly large bacteria can accumulate in it. But can this sponge be cleaned or disinfected? Yes, it turns out, but only as a short-term solution.
Headline : ” Scrubbing a dirty sponge only helps kill the most dangerous bacteria,” says study (New York Times)
History : A team of German scientists analyzed bacteria on 14 kitchen sponges , some of which were cleaned regularly and some were not. The results are of interest to microbiologists, but not groundbreaking for the everyday sponge wearer. To summarize:
- Kitchen sponges contain a lot of bacteria
- None of them are likely to kill you
- After you clean the sponge, it will become dirty again.
When you kill all or most of the bacteria in the germline, the bacteria bounce back, but sometimes the species balance is slightly different from the original: more of one type of bacteria, less of another. Here’s what they found here (although we have to remember that they only studied 14 of the world’s millions of kitchen sponges).
But don’t be afraid of these bacteria: even the “worst” ones mentioned in the New York Times article are pretty harmless. None of them cause disease in healthy people. Even the one they call proven, Moraxella osloensis, can live happily on your skin without causing problems .
Unsurprisingly, skin bacteria show up on objects you touch with your hands, and it certainly doesn’t mean that brushing is useless.
“Please note, we have not directly tested any sponge cleaning methods ourselves,” senior study author Markus Egert told me in an email. He does not yet have data on whether one cleaning method is better than another, but he still believes that cleaning sponges is a good idea and personally prefers to throw them in the washing machine with powdered detergent and bleach.
According to the Michigan State University extension, there are three other methods that effectively kill bacteria:
- Place the damp sponge in the microwave for one minute over high heat.
- Place it in the dishwasher at the longest and hottest temperature (plus the drying cycle)
- Soak in diluted bleach for one minute
Since the bacterial ecosystem of the sponge changes over time, Egert thinks it’s a good idea to donate the kitchen sponge over time for general cleaning tasks (such as using it in the bathroom). But we do not have data on how old the sponge is too old for use in the kitchen, so there are no definite recommendations here.
Conclusion : clean sponges get dirty again, but they still need to be cleaned.