Casu Marzu – Casu frazigu

Casu Marzu – Shardan CC BY-SA 2.5

Casu Marzu – Casu frazigu

Casu Marzu is a cheese made in Sardinia banned in the US and European Union. This cheese contains larvae from P. Case.

From Wikipedia, the free encyclopedia.
The casu fràzigu or casu martzu (in Italian Formaggio Marcio) is a food product of Sardinia characterized by its particular formation process. It is a sheep’s cheese, or preferably goat’s cheese, colonized by the cheese fly’s larvae called the cheese fly (Piophila casei). Depending on the island’s historical regions, it is also known in the Sardinian language as casu marzu, casu mùchidu, casu modde, casu bèiu, casu fatitu, casu giampagadu, casu ‘atu, casu cundítu. It is also produced in Corsica, known as casgiu merzu.

How it is obtained

In the family, it is still obtained naturally by the Piophila casei, also known as cheese fly, an insect from whose eggs, laid in the form of pecorino, larvae are born that draw nourishment by feeding the structure itself and developing inside it. The production period is the spring and summer and can continue until late autumn. During the production of cheese, some tricks are usually used to create favorable conditions for the reproduction of Piophila casei, such as reducing the time of brine or making small holes filled with oil to soften the rind and attract the insect.
Another trick is to limit the turning of the pecorino wheels, which are placed in open rooms, to be attacked (pricked) by the insect that lays its eggs. After hatching, the larvae use their enzymes to transform the pecorino’s cheese paste into a soft cream. The maturation period lasts from three to six months. When the cheese is mature, and the larvae have considerably decreased, the wheel is opened by removing the upper part (su tapu). The inside of the form comprises a homogeneous yellowish cream with a very particular and intense flavor.

Metamorphosis of larvae

We can observe four stages in the metamorphosis process.
egg deposition by the cheese fly
development of the larva that will feed on the cheese
pupa stage
the unfurling of the midge.
Once they have sprouted wings and become midges, the time they have to lay their eggs is minimal: before dying, they must find another wheel of cheese on which to lay their eggs, from which the new generation of larvae will then hatch. In dairies worldwide, these larvae are well known and feared as they attack all types of cheese. As a result, entire batches of cheese can be irreparably contaminated, and at that point, all that is left to do is to destroy part of the dairy’s production and then disinfect the premises.

Protection of the product

The Casu fràzigu is included in the traditional Italian food products of the Ministry of Agriculture, Food, and Forestry. It is one of those that the Region of Sardinia wants to protect and has applied to the European Union for the PDO mark to protect its denomination of origin, Casu Martzu, and safeguard it from food piracy.

Similar cheeses

In Italy there are some cheese varieties that require a biological process of constitution similar to Sardinian cheese, such as:
il marcetto or cace fraceche – Abruzzo, (L’Aquila);
cas cu i vierm – inland area of Potenza, Basilicata;
the gorgonzola with crickets (with “crickets” are dialectally meant the worms in the act of jumping) – Genoa hinterland (Liguria);
il salterello – Friuli, (Udine);
furmai nis (nisso cheese) – Piacenza (Emilia-Romagna)
the Graukäse – Alto Adige, very similar but without the larvae.
il fermagge pengiute (point cheese) – Bari;
casu du quagghiu – Calabria;
caciè punt (point cheese) – Molise;
il bross ch’a marcia (walking cheese) – Piedmont;
casu puntu – Salento.
il formaio coi bai – Veneto.

Casu Marzu – Casu frazigu is a Regional Recipe from Sardinia

Enrico Massetti was born in Milan, Italy.
Now he lives in Washington, DC, USA.
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