What kind of fish is in sushi?
There is a range of types, but one of the most popular is tuna. Remember that the word 'sushi' doesn't actually refer to raw fish, but a boiled rice dish. Lots of sushi does not actually contain fish.
Yes it does but not all sushi has fish in it. "Sushi" is the art of the preparation and the presentation. Tamago, for example is a cooked egg omlet of sorts that is specially seasoned and placed on the formed rice ball in sushi preparation for what is called "nigiri" sushi. And not all sushi contains raw fish. The eel, or Unagi is cooked as is the shrimp. Sashimi is sliced raw fish. Sushi rolls…
What kind of sushi or sashimi would be best for someone who tends to dislike fish if they had to pick one?
If you dislike fish stay away from the sashimi as it is nothing but pure fish...no rice, nothing. For sushi i would recommend "California rolls" (crab and mayo), "vegeterian rolls" (cukes and advocados usually) and some places will have sushi with steak rolled inside (obviously not traditional). And you can never go wrong with "dynamite rolls"! Enjoy!
They roll sushi in many things. The most common thing used is seaweed and crabmeat. That would be your center, then rice and depending on the type of sushi different seasonings go on top. The California roll for example has sesame seeds on top of the rice. Any kind of fish can potentially become sushi.
Which kind of a raw tuna is suitable for sashimi and how can you recognize such a tuna in fishmonger's shop?
You need to go to a good fishmonger and request 'sushi grade' tuna. It will cost more than tuna you buy for cooking. Unless you have been trained on identifying sushi grade fish and know what parasites and imperfections to look for, leave it to the professionals. Another good source is to ask your local sushi shop where they buy their fish from.
What sushi is best depends on what you are looking for from your sushi dish. If you have never tried sushi before it's best to have a basic roll (like the california roll) and a few pieces of nigiri (try egg and crab and a raw fish if you are daring). Also, consider talking to the sushi chef, since he knows the best fish that he has.
Yes because it's raw fish - and raw fish will rot if it's not refrigerated. Sometimes the raw sushi fish is soaked in rice vinegar to "cook" the fish with acid, but at the end of the day the fish is still raw and won't last an hour if left in a car in the summer with the windows up, in pheonix, arizona. Say "sushi fish" ten times fast!
The concern about eating sushi when pregnant is because of the fish... it's thought that these days, because of pollution, there is enough mercury in ocean-caught fish to be a health risk, and this applies to both cooked and raw fish (mercury is a metal and does not cook out). Plenty of sushi rolls are vegetarian, though, and that's some of the healthiest stuff you can eat, pregnant or not. My own thinking, for what…