Sushi-like sour tasting food which includes fish has a pretty long history in Southeastern Asian countries. Originally, sushi was fermented salty and sour fish, which can be preserved. The food was introduced to Japan in the 8th century.
Those type of sushi are called nare-zushi (image to the right), and used cooked rice in between the fish to help the fermentation. Both fish and rice were eaten together when it was ready. This type of sushi still exists at some areas of Japan. Nare-zushi has little resemblance to the modern nigiri-zushi we know. I’ve never had a chance to try nare-zushi myself, but I heard that it has strongly fermented smell.
Nare-zushi has to wait for fermentation to take place, but the Japanese have tried to quicken the process over the time. Eventually vinegar was used to add the sour flavor instantly. Sushi’s “su” means sourness or vinegar.
Currently, there are many forms of sushi in Japan. Nigiri-zushi, which are made by professional sushi chef piece by piece, are the most sophisticated form of sushi. Nigiri-zushi are deceptively simple looking tiny morsels, but it takes years of learning and training to make those properly. Japanese housewives don’t even attempt to make nigiri-zushi. They can be prepared only by professionals.
However, there are several different types of sushi Japanese people regularly make at home. Chirashi-zushi, which means scattered sushi, is one of them. Chirashi-zushi is usually served in a bowl. On the bed of seasoned rice, fish, eggs, vegetables are scattered. When it’s prepared at home more vegetables are used, but many different raw fish are used at sushi restaurants.
Maki-zushi (rolled sushi) is a cylinder shaped sushi wrapped in nori (black seeweed). Sushi restaurants regularly serve them and it requires some practice, but some Japanese housewives can make them quite beautifully.
Temaki-zushi (hand rolled sushi) also can be served at sushi restaurants, but can be made at home easily as self serving sushi. Prepare seasoned rice, nori (black seeweed), and fish or vegetables are put inside of the roll. Raw fish, avocado, cucumber, atsuyaki-tamago (eggs seasoned with dashi and sugar), boiled shrimp, canned tuna fish mixed with mayonnaise can also be put inside. This is great for a party at home.
Another popular home made sushi is inari-zushi (see recipe), which is recommended for vegans and children. In short, it is seasoned rice stuffed in a pouch made of tofu. The pouch is fluffy deep fried tofu called abura-age, and has a pocket inside, just like a pita bread.
Abura-age is sliced in half and stewed in sugar and soy sauce to absorb the flavor.
After I came to the United States, I started to use smoked salmon for sushi (see recipe). It is difficult to get sufficiently fresh fish here, but smoke salmon is readily available in many area. Using plastic wrap, I make bite size seasoned rice balls with a piece of salmon on the top.