Casu Marzu begins as Pecorino Sardo (Fiore Sardo), a cheese that’s typically soaked in brine, smoked, and left to ripen in the cheese cellars of central Sardinia. But to produce Casu Marzu, cheese makers set the Pecorino Sardo outside in the open – uncovered – and allow cheese flies (scientifically named Piophila casei) to lay eggs inside of it.
As the eggs hatch into a myriad of white transparent maggots, they feed on the cheese. By doing so, they produce enzymes that promote fermentation and cause fats within the Casu Marzu to decompose.
Sometimes, cuts are made into the rind of Pecorino Sardo and already-hatched maggots are introduced into the cheese. This speeds the whole cheese making process along.
What does it taste like?
How Casu Marzu TastesCasu Marzu is a local delicacy in very high demand. It’s a highly pungent, super soft cheese that oozes tears (“lagrima”), and fittingly so, as it tends to burn on the tongue.
Some say Casu Marzu tastes like an extremely ripe Gorgonzola. That is, of course, without the savoury blue veins and with a whole lot of larva. One piece of Casu Marzu may be populated by thousands of living, breathing maggots.
In fact, local Sardinians will tell you the spicy, creamy cheese is only okay to eat if the maggots are still moving. Apparently, once the maggots are dead, the Casu Marzu has gone bad – decayed to a point that’s too toxic for human consumption.