Gah! Only a week in, and already I’ve missed out a day. BAD ScienceSponge.
Well, to make up for it, today’s factlet is all about how Penicillium moulds are more than just those annoying patches of fuzzy mould on your week-old bread. Moulds in the Penicillium genus are soil dwelling, and responsible for most cases of food spoilage (along with Aspergillus). But as well as infecting plants, animals and occasionally immunocompromised people, they can in fact be rather useful.
Penicillium chrysogenum is the fungus that was found to produce an antibiotic substance by Alexander Fleming. It releases it in response to stress to compete against other microorganisms in the area. The substance was later developed by Howard Florey and others to produce Penicillin. This antibiotic and its derivatives kill bacteria by preventing them from strengthening their cell walls, and have saved countless lives.
A couple of the relatives of this fungus are very handy when it comes to cheesemaking. P. roqueforti and P. glaucum are both used to produce blue cheeses like Roquefort, Gorgonzola and Stilton. They are mixed into the milk early on and develop the blue veins and pungent flavour of these cheeses. And P. camemberti is sprayed onto the outside of Camembert and Brie cheeses and develops their characteristic white rind. (If you want to know a bit more about cheesemaking, you can watch the Scrapbook video podcast I made on it for the Naked Scientists.)
I’d still stay away from mouldy bread though…