Sushi is vinegar rice, topped with other
ingredients, such as fish. Sliced raw fish alone is called
sashimi, as distinct from sushi.
The common ingredient across all the different kinds of sushi is sushi
rice. The variety in sushi arises from the different fillings and
toppings, condiments, and the way these ingredients are put together.
Sushi is made with white, short-grained, Japanese rice
mixed with a dressing made of rice vinegar, sugar, salt, and occasionally
kombu and sake. The essential quality of
short-grain Japanese rice is its stickiness or
glutinousness. Rice that is too sticky has a mushy texture; if not sticky
enough, it feels dry. It has to be cooled to room temperature before being used
for a filling in a sushi. In some fusion cuisine restaurants, short grain brown
rice and wild rice are also used.
The black seaweed wrappers used for wrapping sushi are
called nori. Nori is a type of algae, traditionally cultivated in the
harbors of Japan. Originally, algae was scraped from dock pilings, rolled out
into thin, edible sheets, and dried in the sun, in a process similar to making
Left: A sheet of nori.
Today, the commercial product is farmed, processed, toasted, packaged, and sold
in standard-size sheets about 18 by 21 centimetres (7.1 by 8.3 in). Higher
quality nori is thick, smooth, shiny, green, and has no holes. When stored for
several months, nori sheets can change color to dark green-brownish.
Fish serves as the common topping or filling for
sushi. For culinary, sanitary, and aesthetic reasons, fish eaten raw must
be fresher and of higher quality than fish which is cooked. Professional sushi
chefs are trained to recognize important attributes, including smell, color,
firmness, and freedom from parasites that may go undetected in commercial
inspection. Commonly-used fish are tuna, Japanese amberjack, yellowtail,
snapper, mackerel, and salmon.
Other seafoods such as squid, eel, conger, octopus, shrimp, clam, fish roe, sea
urchin, crab, and various kinds of shellfish (abalone, prawn, scallop) are the
most popular seafoods in sushi. Oysters, however, are less common, as the taste
is not thought to go well with the rice.
Apart from fish, pickled daikon radish, pickled
vegetables, fermented soybeans, avocado, cucumber, asparagus, yam, pickled ume,
gourd, burdock, and sweet corn may also be
used as toppings and fillings. Tofu
and eggs (in the form of slightly sweet, layered omelette called
Sushi is commonly eaten with condiments. Sushi may be dipped in Shōyu,
soy sauce, and may be flavored with Wasabi, a piquant paste made from the
grated root of the Wasabi japonica plant.
True wasabi has anti-microbial properties and may reduce the risk of food
poisoning. An imitation wasabi (seiyo-wasabi), made from horseradish and mustard
powder and dyed green is common. It is found at lower-end
sushi restaurants and at most restaurants
outside of Japan. If manufactured in Japan, it may be labelled "Japanese
Gari, sweet, pickled ginger, is eaten with
sushi to both cleanse the palate and aid in digestion. In Japan, green tea (ocha)
is invariably served together with sushi.