"My favorite fermented challenge, because I'm a cheese lover but am mortally repulsed by worms, is casu marzu. Casu marzu is a sheep cheese popular on the Italian island of Sardinia. The name means "rotten cheese" or, as it is known colloquially, "maggot cheese," since it is literally riddled with live insect larvae.
To make maggot cheese you start with a slab of local sheep cheese, pecorino sardo, but then let it go beyond normal fermentation to a stage most would consider infested decomposition (because, well, it is).
The larvae of the cheese fly (Piophila casei) are added to the cheese, and the acid from their digestive systems breaks down the cheese's fats, making the final product soft and liquidy. By the time it is ready for consumption, a typical casu marzu contains thousands of larvae.
Locals consider it unsafe to eat casu marzu once the larvae have died, so it is served while the translucent white worms, about one-third of an inch long, are still squiggling. Some people clear the maggots from the cheese before consuming it; others do not. Those who leave the maggots may have to cover the cheese with their hands—when disturbed, the maggots can jump up to six inches.
It is no accident that you likely feel revolted by many of these descriptions. The most elemental purpose of the emotion of disgust is to make us avoid rotted and toxic food."
Revolted? Disgusted? Yes. Eating maggot-filled cheese or recently-filled-with-maggot cheese is gross any way I look at it.
Also disgusting? It's made from sheep cheese. If people are buying, let's get it made out of cow milk, at LEAST.