Food Becomes You: Swimming in Sushi

By Wendy Gordon

Once exotic, sushi has made its way into the American mainstream. Shopping malls boast sushi bars; super markets sell plastic trayfuls of the stuff. Most Americans identify sushi with raw fish, but technically the term "sushi" refers to the specifically textured, vinegared rice. Beyond the rice, the contents of sushi are limited only by one's imagination. While raw fish is certainly one of the most traditional ingredients, cooked fish is also common, as are cucumbers, avocado, eggs, and tofu. Broccoli, red pepper, smoked salmon and even pork or ham have worked their way into sushi.

In its earliest form, centuries ago in Japan, dried fish was placed between two pieces of vinegared rice as a way of preserving it. The nori (seaweed) was added as a way to keep one's fingers from getting sticky.

Sushi is as much an art form as it is a food. The different names you see on a sushi bar menu are based on the style of preparation more than the contents. The same ingredients may be assembled in entirely different ways to different effect.

Makizuahi, or rolled sushi, is the form of sushi most familiar to Westerners. Two or three fillings are rolled up with rice in a sheet of nori, and then cut into six pieces. California rolls are probably the most common example of this type of sushi. The ingredients can also be rolled "inside out": veggies and nori on the inside, rice on the outside, in which case they are known as uramaki. Temaki are hand rolls, cones of nori filled with rice and other ingredients. Nigirizushi refers to hand-formed sushi, assembled without rolling and often tied up with a ribbon of nori. Less commonly seen are oshizushi, or pressed sushi (made with a mold) or inarizushi, a small pouch made from deep-fried tofu or eggs, and filled with rice and other fillings.

Sushi is often confused with sashimi. Sashimi does refer to raw fish--just fish--sliced thinly and served without the mitigating presence of the rice. When exquisitely fresh, it can be delicious but is a more acquired taste than sushi.

A trio of condiments accompany sushi on the plate. Shoyu is traditional soy sauce (different than the caramel-colored Chun King stuff). Soybeans, wheat, and salt are combined with water and a mold called "koji&qout;. Koji converts some of the sugars into alcohol, similar to the process of making beer or wine. Other enzymatic and chemical reactions also occur, and after a time the blackened liquid known as shoyu results.

Wasabi, that sinus clearing bright green paste, is made from a horseradish-like rhizome. Wasabi root is rarely grown outside of Japan, and what we think of as wasabi is actually garden-variety horseradish with food coloring. Traditional wasabi is sold in Japan and by mail-order in the US. It's extremely expensive, and while it may contain a few more subtle flavor notes, it doesn't really taste all that different.

Pickled ginger is the third member of the essential condiment trio. Ginger is sold in a seasoned vinegar marinade, grated or sliced razor-thin. Again, food color ing is used with abandon, resulting in the pinkish-orange shade we commonly see. Uncolored (tan) ginger is supposed to have a superior flavor, but I have never seen it in the market. You can easily make your own, though, by grating ginger root and combining it with seasoned rice vinegar.

Large green shiso leaves and shredded Japanese white radish (daikon) are often served with sashimi.

Many people worry about the safety of raw fish, and with good reason. Raw fish may contain parasitic or bacterial contaminants. Sometimes the illnesses they cause are hard to trace back to the fish, because the symptoms occur days after eating it. Saltwater fish are much less likely to be contaminated than freshwater, and within the saltwater category fish that travel widely (like tuna) are less likely to be infected than those which are reef-bound (like sea bass or grouper) Anisakiasis is a particularly dangerous gastrointestinal infection that is caused by microscopic roundworms that infest finned fish, and there are rare reports of infested yellowfin causing human illness. Raw wild-caught salmon, because it spends part of its life in freshwater, is particularly prone to roundworms. Fish caught in polluted waters may also carry hepatitis A, staphylococcus, or amoebas...

Because of these dangers, raw fish is best eaten in a restaurant or bought from a market with a sushi bar. Reputable sushi restaurants and markets are very careful about their fish sources, buying only "sushi grade" seafood. Careful chefs and fishmongers look for fresh fish; bright clear eyes; bright red gills; secure scales; "bouncy" skin, and a clean smell. Much of this fish is flash frozen within hours of harvesting, which preserves freshness and kills any parasites that the fish may harbor. Home freezers cannot match the rapid deep freezing of these professional cooling devices. When patronizing sushi bars, look for ones with open, sparkling clean kitchens, no fishy odor, and a brisk business with lots of turnover While "conveyor belt" sushi restaurants are popular, I prefer restaurants where the sushi is made to order and not potentially touched by so many hands.

If you want to make sushi at home, I would suggest using cooked seafood (crab, shrimp, high quality canned tuna, and smoked salmon all work great), tofu, and vegetables. You may be able to locate a store that sells sushi grade fish to the public. If there is an Asian market in your area, I would definitely check that out.

Sushi is one of those rarities, a low calorie food with the feeling of luxury. Calorie counts vary according to the fillings and thickness of the roll but rarely exceed fifty calories for two pieces. A typical restaurant sushi plate of ten pieces amounts to roughly 450 kcal. While white rice is not a nutrition powerhouse, many of the fish are excellent sources of essential fatty acids and iron. Some sea creatures, such as eels and sea urchin, provide lots of vitamin A. Nori seaweed used to be scraped from docks and dried; now the Japanese farm it in large sea forests. It packs a remarkable amount of nutrition in a virtually calorie-free package: low in sodium, high in fiber, and forty percent protein.

Making sushi at home can be fun but requires skill, practice, and investment in a few pieces of basic equipment. You will need a sharp knife, a bamboo rolling mat, and chopsticks for positioning small pieces of filling.

Proper rice preperation is essential to successful sushi. Rice that is not sticky enough will fall apart and rice that is too sticky won't roll properly and will taste gluey. You are best off buying rice that is specifically intended for sushi (Japonica is the traditional variety), but in a pinch other short-grain rices, such as Arborio, will do. The proportion of water is less than the 1.5/1 ratio generally recommended for long grain rice. Some recipes call for a 1:1 ratio, and others for a 1:25/1. You are best off experimenting and discovering what works best for you. Some recipes call for the rice to be rinsed several times before cooking, but this recommendation dates back to the time when rice was dusted with talc. Now rice is usually coated with cereal starch, so this step can be omitted. Bring the rice and water to a quick boil, simmer covered for approximately 20 minutes (or until all the water is absorbed), and then let it stand for 10 minutes after removing it from the heat. Some recipes recommend a rice cooker, but I do not think that is strictly necessary.

The hot rice then needs to be transferred to a bowl and mixed with flavored vinegar. Seasoned rice vinegar works just fine, or you can make your own, combining one-third cup white vinegar, 2 tablespoons sugar, and one and a half teaspoons salt in a small saucepan. Bring to a boil, stir until the sugar and salt are dissolved, then remove from the heat. Use one tablespoon of vinegar per cup of rice. Mix it into the rice with quick strokes, fanning the rice at the same time to cool it quickly.

California Roll

Almost everybody likes California rolls! They are a great first introduction to sushi. California rolls contain crab, avocado, and cucumber, and of course, sushi rice and nori. Many rolls are made with imitation crab, but I'd recommend the real thing if it all possible.

You will need a bamboo sushi mat (available in Aisle 6). Place a sheet of plastic wrap on top of the bamboo mat. Lay one piece of toasted sushi nori on the plastic, and spread about a cup of rice over the nori, leaving about an inch of uncovered nori at one end farthest from you. The rice should be less than a quarter inch thick or it will be hard to roll. Put avocado slices, one slice thick, on top of the rice, near the edge closest to you. Top the avocado with a piece of crab meat. Then add several small strips of cucumber next to the crab and on top of the avocado.

Slowly fold the mat over, tucking the end of the nori to start the roll. Continue rolling with medium pressure, lifting up the mat and plastic wrap as you go. Remove the roll from the mat and cut it into six even pieces with a moistened knife. Serve with wasabi, ginger, and a small bowl of shoyu. (For instructions with pictures, go to www.edenfoods.com/issues_sushi_steps. html.

Wendy Gordon is a writer and restaurant reviewer who lives in Portland, Oregon. She has a Masters Degree in Clinical Nutrition from the University of Chicago, and is on the Board of Directors of Food Front Grocery, a co-op in Portland.