One of the wonderful things about sushi is you don't always need to know the names of every item to be able to enjoy it, particularly if you frequent conveyor belt sushi restaurants, where you're free to select any delicacy that catches your eye.
But if you're ordering off a menu, it helps to have at least come familiarity with the main types of sushi, so that you know approximately what you'll be getting if you order each one. And in Japan, at least, the most popular type of sushi is called nigiri.
But First, What Is Sushi?
At its most basic, sushi is a Japanese dish featuring specially prepared rice and usually some type of fish or seafood, often raw, but sometimes cooked.
Sushi can be prepared in a number of ways and though the word sushi is often automatically associated with raw fish, the most important ingredient is vinegared rice. In fact, the word "sushi" is an amalgam of the Japanese words for vinegar and rice. The toppings and fillings can vary, but sushi always includes rice.
Sushi rice is a vast topic unto itself and sushi chefs in Japan undergo years of training just to learn how to make sushi rice before they ever pick up a knife and start cutting up fish.
But sushi rice in a nutshell is a medium-grained white rice that is prepared with vinegar and other seasonings such as salt and sugar. When properly prepared, sushi rice will have a sticky consistency that allows it to be molded or rolled into shape.
What Is Nigiri?
Which brings us to nigiri. Nigiri is that familiar style of sushi made up of an oval-shaped mound of rice with a slice of (usually) raw fish on top. The word nigiri comes from the Japanese nigirizushi, which translates as "hand-pressed sushi."
Thus nigiri is a type of sushi where the rice is molded by hand and the fish or other topping pressed by hand atop the rice. And it's the stickiness of the rice, combined with the moisture from the topping, that helps to adhere the strip of raw fish to the mound of rice underneath.
Occasionally the chef will place a small amount of wasabi between the rice and the fish. Some type of garnish, such as minced scallions or ginger, atop the fish is also common.
The fish is almost always raw. Typical examples include tuna, salmon, and yellowtail. Fatty tuna, which comes from the belly section of bluefin tuna, is another popular topping.
A couple of notable exceptions to the "almost always raw" statement include shrimp nigiri, which features shrimp that has been boiled and butterflied, and eel nigiri, which consists of a mound of sushi rice with a strip of grilled eel on top.
Whether cooked or raw, the fish and seafood for nigiri, and indeed for all sushi, must be exceedingly fresh and handled with great care.
Although sushi restaurants do offer chopsticks, the preferred method for eating sushi is to pick it up with your fingers and eat each piece in a single bite. Sushi etiquette is another extensive topic that requires deep exploration, but in general, nigiri should be dipped in the soy sauce so that the fish, not the rice, is immersed, and eaten upside down with the fish against your tongue.
The reason for dipping the sushi fish side down is so that the rice doesn't absorb too much soy sauce and also so that the soy sauce doesn't end up with grains of rice in it.
Nigiri Versus Maki
Nigiri sushi is distinct from what is, in the U.S. at least, the most popular type of sushi which happens to be the rolled style, known as maki.
Maki is shaped like a tube, held together by a sheet of dried seaweed called nori, with a layer of rice and then a layer of fillings, which can include ingredients such as raw fish, cooked shellfish, vegetables, and even cream cheese.
The rolled tube is then sliced into individual bite-sized sections. Sometimes the roll is constructed inside out, so that the rice is on the outside and versions with a thin strip of fish, eel or shrimp on the outside are also common. Like nigiri, maki is also best eaten by hand.
Nigiri Versus Sashimi
Another item that is common to Japanese sushi restaurants is sashimi, which is simply strips of raw fish with no rice at all (although rice can accompany sashimi). As such, sashimi is not technically a type of sushi, since sushi always features rice. Unlike nigiri and maki, sashimi is eaten with chopsticks.
Types of Nigiri Sushi
In addition to the main type of nigiri sushi described above, there is something called gunkan-maki. Gunkan-maki is a type of nigiri featuring some sort of soft or semi-liquid topping, such as minced tuna, fish roe, or sea urchin.
Gunkan-maki is thus distinguished by the fact that it has a strip of nori wrapped around the perimeter of the rice mound, making it look something like a battleship. The top edge extends above the rice, forming a sort of bowl or receptacle which holds the topping in place.
Another variation or subtype of nigiri is known as nori-ribbon nigiri, in which the topping is secured to the mound of rice by a thin strip of nori that is tied or affixed vertically around the nigiri. This is done when the topping lacks sufficient moisture to adhere to the rice properly, such as in unagi, made with strips of grilled or simmered eel, and tamagoyaki, which features a topping of sweetened omelet.