I would appreciate answer soon, as the event is tomorrow. Thank you.
Commercial grade freezing is usually considered a way to make raw fish safer, because it kills parasitic worms that could be living in the raw fish flesh.
The FDA seems says that it is ok, http://www.fda.gov/food...
Sorry, for double posting. Anyhoo, most of the sushi that we consume in the US has been previously frozen to kill most parasites. So I think you'll be fine.
Thanks for the quick, helpful responses! Food 52 is great.
I have made this recipe several times but with fresh tuna, excellent recipe!! Enjoy!