Asked by: Jo Drysdale, Bristol
The same bacteria that is used to ripen many cheeses, including Munster, Limburger and Port-du-Salut, also lives on our skin and eats dead skin cells. It’s called Brevibacterium; as it digests it gives off S-methyl thioesters, which smell cheesy.
Another skin-munching bacterium is Staphylococcus epidermidis, which produces the cheesy, vinegary-smelling isovaleric acid. The final ingredient in this ‘socktail’ is Propionibacterium, which converts sweat into the sour-smelling propanoic acid.