Excerpts from Sushi, by Mia Detrick
"Nigirizushi can be made with almost any freshly caught saltwater fish, shellfish, or high-quality processed
roe. Find yourself an excellent fish market and learn to recognize freshness and quality in all of these items.
When selecting a fish, look it in the eyes. They should be clear and bright, never cloudy. The gills should be bright red inside and the whole fish should smell fresh as a sea breeze, have no trace of sliminess, and be resilient to the touch.
Although the sushi chef buys his fish whole, you will probably want to have your selections cleaned, skinned, and filleted for you. One pound of cleaned fish will make two dozen sushi, and serve eight to twelve people as appetizers, four for a main meal. Keep it chilled until the last possible moment. Then place the fish on a cutting board, and with a very sharp knife cut the fillet across the grain into quarter-inch-thick slices, then trim them to form one-by-two-inch sections.
Pick up the fish morsel with your left hand, holding it gently between thumb and forefinger, and hold a rice pad in your right hand . Brush a streak of wasabi (buy it powdered in an Oriental market) down the center of the fish slice with your right forefinger . Cradle the fish slice in your left hand and press the rice pad into it . Then roll the sushi, fish side up, onto your fingers  and press in the top and sides to firm its shape . Place it on the serving tray .
Clams should be bought when they are tightly closed to be sure they are alive. Clams with protruding siphons will constrict somewhat when touched, indicating they are still alive and fresh. If you dig clams yourself, be sure to obey quarantine laws during the summer months. They are for your protection, not the clam's. Cover the clams with salted water and let them stand for fifteen minutes to rid them of sand, which will settle to the bottom of the bucket. Change the water and let the clams stand several times until no more sand appears.
Open and scoop small clams from their shells and rinse them in cold salted water and drain. Clams may be sliced nearly in half and spread open, butterflied, for a thinner and more manageable sushi. With large clams, open the shell and remove the body. Cut away the digestive organs, leaving the firm, meaty muscle. Slice the muscle thinly and add salt, massage well, then rinse under cold water. Score the slices with a sharp knife to make them more tender. Clams are pressed onto sushi rice as above.
Shrimp is very popular in sushi bars, and although raw shrimp is considered a great delicacy, it is not recommended unless the shrimp are purchased live and from pure waters. Most shrimp sold in the United States are frozen and should be cooked. If you do find fresh shrimp for sale, they should be firm, with tight-fitting shells, and should smell fresh. A stale shrimp has the smell of ammonia, and if even one smells bad, the whole batch is on its way out.
To cook shrimp, devein them, and leaving the shells on, skewer them on toothpicks to prevent them from curling as they cook. Drop them into boiling salted water to which you have added a dash of rice vinegar. Boil the shrimp for three minutes, until they turn opaque and pink, then plunge them into cold water. Remove the toothpicks and peel the shrimp, leaving the tails on for decoration. Split each down the underside, taking care not to cut all the way through. Spread open into a butterfly shape, and press the shrimp onto a rice pad as you did with sliced fish.
To make roe sushi, or any gunkan-style nigirizushi, toast a sheet of nori seaweed (available in cellophane packages in Japanese markets) over an open flame until it turns a bright green. Cut it into one-by-six-inch strips and wrap each one around a rice pad, sealing the hand with a bit of smashed rice. Spoon in roe, bits of fish or shellfish, and garnish with a sprinkle of lemon juice, a dot of wasabi, or a fresh quail egg.
To make two dozen salmon roe sushi, you will need two four-ounce jars of salmon roe and four or five sheets of nori. Seaweed loses its crispness quickly, so this type of sushi should be made just before serving.
Makizushi is a bit easier to make than nigirizushi. You will need a bamboo rolling mat, available in
Japanese stores, plus sushi rice, nori seaweed, and whatever ingredients you want to put inside -- sliced
cucumbers, bits of fish, pickled vegetables.
Toast a sheet of nori as for gunkan-style nigirizushi. Then place it on the bamboo mat, shiny side down .
The mat should lie so it rolls away from you, not from side to side. Keeping your hands moistened with
vinegar water, put two or three tablespoons of sushi rice in the center of the nori and spread evenly, about
three-eighths inch thick, over the seaweed .
Use the palm of your free hand at the side of the seaweed to form a firm edge, and leave a one-inch margin
at the top of the nori to seal the roll. Spread a streak of wasabi across the middle, then add layers of
fish and vegetables across the center of the rice .
To roll, fold the bamboo mat so the filling is enclosed in the center of the nori (4]. Press the mat around
the roll for about thirty seconds to shape it . then moisten the margin of seaweed and seal the roll as
tightly as possible. The most difficult part of making makizushi is getting the roll tight enough to prevent
it from disintegrating when it's sliced.
Remove the mat from around the roll, press in the loose ends and place it oil a cutting board, seam side
down. Slice the roll into one-inch rounds, using a wet, sharp knife . Do not saw, but cut firmly, straight
down, or the roll will come apart. Turn the slices rice side up for decorative effect."
Tomorrow: Last Lesson, what else? The Rice!