Eat raw fish safely: how to do it at home (and at the restaurant)

Raw fish is a dish that has now spread steadily on our tables. In the seaside places it was tasted even before, but the cruditè (so often called in the menus) and / or carpaccio have conquered more and more palates thanks to the flourishing of the numerous Japanese restaurants and – in return – many Italian chefs have begun to propose them in their own version . Even at home, someone prefers raw fish on hot and sultry days.

The parasite of fish

Raw fish, however, poses problems not only of conservation (with high temperatures), but also of food safetygiven that it can house inside, often unnoticed, the parasite called anisakis. It is a parasitic worm of fish and shellfish that can infect salmon, herring, cod, mackerel, squid, halibut, snapper and others. From raw fish the larva passes to the human intestine causing pain, nausea and vomiting. Some patients may develop allergic reactions, swelling, skin rash, or anaphylactic manifestations. The anisakis larva can live for weeks in the digestive system, but dies before reaching adulthood. Before dying, however, it produces an inflamed mass in the esophagus, stomach or intestines. Diagnosis can be made bygastroscopic examination during which the larvae are visualized and removed.

How to kill the larvae

How to avoid taking risks? The anisakis larvae are not that small (they can be up to 2-3 centimeters long), so they could also be seen when cutting fish. The safest way, though, is freeze the fish then eat it raw later. Restaurants have to do this by law. According to the Centers for Disease Control and Prevention (CDC) in the United States, 15 hours at -35 ° C are sufficient, a temperature that can be reached thanks to the use of a professional blast chiller. In the case of home freezers, which do not allow the minimum necessary temperature to be reached, the freezing times must be extended: 7 days at -20 ° C.