Only add the amount of soy sauce you need, rather than filling your sauce dish to the top. Once you have those things you can watch this video tutorial on how to clean Ahi Tuna for sushi and sashimi (part 1). The second part I will follow up with how to clean the belly for tuna rolls or tartar along with slicing the loins for the sashimi. The slices should be about 2.5 cm wide, 4 cm long and 0.5 cm thick. Wash frozen fish with tap water. Few foods can rival a sliver of raw fish, impeccably fresh and minimally adorned, whether it's perched atop a mound of sushi rice or swimming in a spicy citrus bath.And yet, despite the popularity of incredibly simple dishes like sushi, sashimi, crudo, poke, and tartares on restaurant menus, for many cooks, preparing raw fish at home remains a daunting task. Most of the cases have occurred in Colorado and New Mexico. Second you need to find a good source for high quality tuna. Basic sashimi etiquette. It should be as salty as the sea. To confirm it is salty enough, the frozen fish should float, not sink. Cut off any dark portions and throw away. (it will not be thawed at this point) Remove from the salt water and pat dry with paper towels. You probably only need around half a teaspoon. Cut straight down, cutting against the grain (the grain is the faint lines in the meat). Prepare a bath of lukewarm (35-40C) water saturated with salt. To get rid of germs, the Centers For Disease Control (CDC) says you should clean your produce before you cut, eat, or cook it. If you want to eliminate any "fishy" odor, pour a small amount of milk (or cream) over the fish. Experts recommend washing all produce under running water and drying with a clean cloth towel or paper towel to further reduce bacteria that may be present on the surface. An outbreak of listeriosis linked to cantaloupes has led to the deaths of four people. If you want to eat sashimi as the Japanese do, there are a few rules to follow. The Department of Agriculture do not recommend washing meat or poultry before cooking it.. Generally speaking, washing can be a useful way of removing bacteria. This realy does work! When ready to cut, get a sharp long knife (be careful). Other than that, it is not necessary to rinse the fillet. Let the fish sit for 3-4 minutes. You can always add more if necessary. You would do it with fresh catch only to remove any potentially loose scales. Wash the fish in cold water.