2, followed by running water defrosting, preferably sealed bags vacuum, at least with a plastic wrap wrapped in a plastic bag, put on the tap under the rinse, the cold flow of water defrosting, the loss of water is less, the defrosting time is fast, but a waste of water! Large pieces of fish are easy to surface fish temperature to room temperature, the internal has not been thawed, the surface of the fish for a long time may not be fresh
Note: tuna is generally eaten raw or fried to half-cooked, so in the defrosting process, be sure to seal, so as not to cause contamination