How can I tell if a fish can safely be prepared "crudo"?

Question

Is there something you can look for? Am I left to the seller's word and my own discernment?

Answer 1

General food safety guidelines give you four hours of time between 40F and 140F; more than that, and unsavory bacteria exceed nominally safe limits.

So, there's your safety limit. Total time counts, that is, in a bag back from the grocer for 2 hours, then in the fridge and back down to 34F and then out for 1 hour on the counter = 1 hour left until it needs to go over 140 for ten minutes (or 165 for 1 minute) or into your mouth.

And of course, there's the amount of time it was left on the dock, etc. etc.

That said, if you left fish in the fridge for a week, it would be mushy and bad tasting raw -- so you also must use your tastebuds and nose to see if you want to eat it raw; food safety isn't the only concern.

Answer 2

Well, your discernment is indeed what you are looking for. You want really fresh fish. The usual advice for detecting really fresh fish apply. It can't hurt to have a fish source that you have good reason to trust.