https://www.thekitchn.com/what-is-su...ligence-204696
What is sushi grade fish?
Although stores use the label “sushi grade fish,” there are no official standards for using this label. The only regulation is that parasitic fish, such as salmon, should be frozen to kill any parasites before being consumed raw. The best practice for this is flash freezing on the boat immediately after the fish is caught, which preserves freshness and texture.
The label sushi grade means that it is the highest quality fish the store is offering, and the one they feel confident can be eaten raw. Tuna, for example, is inspected and then graded by the wholesalers. The best ones are assigned Grade 1, which is usually what will be sold as sushi grade.
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