We've bought some fresh sushi-grade mackerel, and would like to make saba sushi from it. We were told that we should treat it with vinegar to kill any parasites.
Some online recipes I've seen recommend a two step process of first salting for 30-40 mins, then marinating in vinegar for 30-40 mins. Others extend the salt step to 3 hours.
Is the salting necessary for de-parasiting? I ask because the fish store guys, who are usually very knowledgeable, didn't mention it. If so, is 3-4 hours really necessary, or is 30-40 minutes more like it?
Clearly I'm eager to eat this fish, but I'd like to play it safe :)