Kitchen sponge gross? Here’s why.

Kitchen sponge gross? Here’s why.


Even if your kitchen is spotless, your kitchen sponge might be loaded with bacteria. But take heart: it’s not a sign of kitchen uncleanliness. In fact, new research shows it has to do with the way sponges are built.

Duke University researchers have uncovered a common but uncomfortable truth: The kitchen sponge is a better bacterial incubator than a laboratory Petri dish. And it’s not just about the food residue trapped in a sponge. It has as much to do with the structure of the sponge itself.

Kitchen sponges are separated into different sections of various sizes. The researchers determined structure — known as spatial partitioning — is an ideal home for various bacteria. The germs, it turns out, are like people: Some prefer to be around other organisms. Others like being by themselves. And the typical kitchen sponge accommodates both environments, leading to a bacterial boom.

To establish their findings, the scientists tested the types and amounts of bacteria living in kitchen sponges. A sponge, the researchers concluded, contains many chambers and small wells that offer an optimal breeding ground for bacteria.

What’s the best way to keep bacteria at bay? The short answer is to discard or disinfect them. A scientific study published in 2017 suggests replacing kitchen sponges every week. If that feels inconvenient or wasteful, the U.S. Department of Agriculture recommends wetting the sponge and heating it in a microwave for one minute. Another option is putting the sponge in the dishwasher during a heated drying cycle. Both methods kill more than 99.99% of bacteria.

So, as you’re tidying up after dinner, don’t overlook the humble kitchen sponge.

 

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