Sponges: from microwave to boiling water, how to disinfect them and precautions to take

In the kitchen, there are little gestures we repeat automatically… and which sometimes conceal bigger questions. The sponge, for example: we rinse it, wring it out, and put it back on the edge of the sink, thinking we’re doing the right thing. Yet, behind its harmless appearance, it can become a veritable invisible breeding ground. Should we microwave it? Boil it? Or replace it more often than we think? Before changing your habits, there are a few truths worth knowing.

Why does the sponge so quickly become a breeding ground for microbes?

Unfortunately, the kitchen sponge ticks all the boxes for absolute comfort… for bacteria. It stays damp, absorbs food residue, and is handled several times a day. Its highly porous structure retains water and dirt, creating a perfect environment for rapid and invisible proliferation. According to Francesco Poliandri, a culinary consultant and food hygiene specialist, microorganisms settle deep within the fibers and form a kind of natural shield. The result: a simple rinse with clean water gives an illusion of cleanliness, but is absolutely insufficient.