The growing popularity of sushi has caused some concern regarding its health benefits. Like any other food, there is a risk of getting food poisoning from sushi if the ingredients are old, not refrigerated or not handled according to food and safety regulations. Always make sure that you consume sushi from a trusted source and the busier the shop, the more likely the food is fresh.
In order to avoid food poisoning from sushi, it is vital that the preparation area and equipment used is clean, particularly as the process involves the handling of raw food. In sushi bars, any display cabinet must have doors in order to protect the food from contamination and ensure the correct temperature is maintained. A popular way of eating sushi involves picking up plates from a conveyor system in which case all plates should be covered.
The greatest cause of food poisoning from sushi comes from fact that raw fish is the main ingredient. Anisakiasis is the name of a condition caused by the ingestion of larvae of roundworms or nematodes that are sometimes present in raw fish. People become infected when they eat raw or undercooked fish which were hosts to the roundworm. The anisakid larvae penetrate the gastric and intestinal mucosa, which causes acute symptoms of food poisoning such as severe abdominal pain, nausea and vomiting.
The only way to prevent accidental ingestion of the anisakid larvae is to eat fish that has been cooked or frozen at recommended temperatures which kills the larvae. Care should be taken when ordering sushi in any restaurant that does not use fish that has been frozen first. The incidence of food poisoning from sushi is higher in areas where raw fish is eaten more often such as Japan and the Netherlands.
Many of the fish, particularly tuna and salmon, used in the making of sushi have been found to contain levels of pollutants such as mercury significantly higher than the recommended limits. This is only true of fish caught coastally, however, and does not normally apply to farmed fish. An awareness of where the fish comes from is important for this reason.
Another ingredient in sushi is acidified rice. Acidification of rice to a recommended level using rice vinegar helps in the prevention of the growth of pathogenic bacteria. There are cases, however, where the rice has not been acidified to an appropriate level and, if kept at room temperature for more than a few hours, this could also lead to problems such as food poisoning.
In order to prevent food poisoning from sushi, knowledge of the process of its manufacture and the source of the ingredients used is vital. Restaurants and sushi bars should be clean to the point of sterility due to the fact that raw food needs to be handled correctly according to food safety regulations. Anyone preparing sushi at home should also be aware of the need to follow strict guidelines.