Final answer:
The most common non-fish ingredients in sushi rolls are seaweed and rice. These two components are fundamental to sushi structure, whereas health risks such as parasitic infections from raw fish, specifically from Diphyllobothrium species, should be considered when consuming sushi.
Step-by-step explanation:
The two most common non-fish ingredients used in sushi rolls are seaweed and rice. While ingredients such as avocado, cucumber, tuna, salmon, soy sauce, and wasabi are also popular, seaweed and rice are fundamental to the structure of most sushi rolls. Seaweed, often referred to as nori, is the outer layer that holds the sushi together, and rice is the essential sticky base that complements the soft texture of the fish and the other components.
Regarding health concerns, it is important to be aware that sushi containing raw fish, such as tuna or salmon, can carry the risk of parasitic infections, like those caused by Diphyllobothrium species, commonly known as fish tapeworms. Proper handling and preparation are crucial to prevent foodborne illnesses. Despite the popularity of sushi and sashimi, consumers should be informed about the potential risks linked to consuming undercooked or raw fish.