Egg sushi is seldom ordered or hardly even noticed today. It is a traditional Edo style sushi which dates back to the earliest days and unfortunately most of its tradition has been forgotten. Egg sushi is usually ordered last and treated similar to as a dessert. It is cooked slightly sweet and acts as an appetite suppressant.

Egg sushi used to be a big deal in the old days and is nothing compared to what you typically see in sushi restaurants today. They consisted of ground white fish (halibut, red snapper..etc), reduced rice wine, sweet rice wine, bonito broth, and grated yamaimo which is a potato root local to Japan. The omelets took about an hour to cook both sides on very low heat. This made the omelet very fluffy and the texture becomes similar to a sponge cake, while the ground fish added deeper flavor to the omelet. The omelet were made thinner and made into nigiri sushi with the now seldom practiced hontegaeshi method so the egg sushi sticked to the rice without using a belt of nori to fasten the egg to the sushi rice(see typical egg sushi image). 

Recent egg sushi are made as thick omelets, and consist of egg, bonito broth, and sugar. Some sushi restaurants still make the old fashion egg sushi (left image), but they are thicker, and are not made into the jigami style(left image) which requires more skill.  

[Via Hot Pepper &  Kanpachi Sushi  ]

Osaka’s boxed style sushi (Hako Sushi, Hakozushi) is a traditional form of sushi unique to the Osaka region. Unlike Tokyo’s Edo style sushi, all the ingredients are either cooked or cured. They are not made with the hands and instead use a square or rectangular shaped sushi box (oshigata) which acts as a mold (right image). The sushi box is first filled with sushi rice, and then thinly cut individually sized ingredients are placed on top so they neatly fill the whole surface of the sushi box. Sometimes an extra layer of ingredients are placed in between the sushi rice as seen in the left image. They are then pressed with the lid, and result in a big block of sushi. The sushi are cut into individual sizes before they are served. The ingredients used in this particular Osaka style sushi are, sea eel, cured red snapper, egg omelet, and poached shrimp. Osaka’s boxed mackerel sushi is made in the same fashion, but with a longer rectangular box. 

There is a rarely known area of the blue fin tuna that has an equal amount of fat content as the widely known toro (tuna belly) and that is the flesh around the collar bone (kama). This section is nicknamed the “kama toro”, and is rarer and more expensive than the regular toro sections. The marbling patterns of the kama toro resemble a hanger steak, and it is sliced against its grain. The section is very soft and melts as you put it in your mouth. The kama toro is high in fat, but has a more concentrated taste than the toro sections from the belly since it is close to the gills and there is more blood flow to the muscles in this area.    

Fatty tuna or toro is a rich section of the tuna that is enjoyed by many sushi lovers around the world. In most cases, toro refers to the belly section of the blue fin tuna which has a higher fat content than the rest of the tuna. The tuna belly is classified into 3 sections medium (chutoro), regular (toro), and supreme (otoro). These sections are expensive compared to other fish since they only consist of about 15 to 20% of the whole tuna, and the amount available for each tuna vary and are unpredictable every day.

Moreover, the kama toro only consists of less than 1% of the tuna body and not many people have heard of it or tasted it before. When blue fin tuna is imported to the United States or other countries around the globe, the head section (where the collar bone is located) is usually removed since they are considered scrapings or trimmings. But this is not true to some chefs that know their tuna. Unfortunately, it is rare for an average sushi restaurants even in Japan to carry this section, and you may have to travel to cities close to major fishing ports in to enjoy this sushi. Even if they had it, they would probably not put it on the menu and wait for customers who know about it to order them. So now you are one of those cool customers .

[Via Uomaru]

Shrimp sushi has definitely lost its reputation throughout these years. Unfortunately, smaller and cheaper alternatives are used for the scarcity of the originally used kuruma shrimp(above images). There are many species of shrimp but the kuruma shrimp was solely used for Edo style sushi, since it was the best shrimp available around the current Tokyo bay. Kuruma shrimp is also available in the west coasts of Africa, the Red Sea and South East Asia, but they are becoming rare and expensive, therefore seldom make it to an average sushi bar in Japan. They are hardly ever seen in sushi bars in the western world.   

[Via tripvader & yasuki sushi]

The black tiger shrimp (left) is a delicious shrimp and they are very abundant. It is what you typically see at your local sushi restaurant and is the best alternative to the kuruma shrimp, but when they are compared, there is no match. The kuruma shrimp is much larger, has a meatier flesh, and has a sweeter aftertaste. The black tiger  shrimp is not jucy and tasty enough to match with the sushi rice. Kuruma shrimp is considered tasty as much as Japanese Ise lobster (Ise-ebi), and they are enjoyed not only as sushi.

 [Via maracus]

Sea urchin sushi or uni sushi is usually made in to a ship roll (gunkanmaki). The reason for this is that the sea urchin is very loose and fragile that it can be disfigured if squeezed into a nigiri. The ship roll is not officially a traditional Edo style sushi, and it was only a solution to hold loose sushi ingredients. Many people say that the strong ocean scent of the seaweed (nori) interfered with the aromas of the sea urchin which totally goes against the traditions of Edo style sushi which is to intensify the flavors and aromas of the single and main ingredient.   

A radical sushi chef  thought of a way of making a ship roll with thinly sliced cucumbers(right image). This was a very good alternative to the regular ship roll since cucumbers have less aroma than seaweed. However, cucumber is considered an independent ingredient in Edo style sushi, and the water content slightly diluted the sea urchin’s flavors which created a different concern.  The crisp texture from the cucumber was also another concern. Chefs continued to think of a way to make the sea urchin sushi without extra ingredients that can alter its taste and the best way was to divert back to the basics.

The only way to make the sea urchin into a nigiri (left image)was to constrict its flesh (sea urchin is a gonad) and the best way to do it was to use a mild acid. A marinade made of sudachi juice diluted with kombu broth and reduced rice wine was used to immerse the sea urchin for a few minutes and this helped tightening the sea urchin just enough to retain its creaminess and natural flavors. It is still loose, so the nigiri is quickly made by the tategaeshi (vertical flip) method.

[Via Tokyo Selection & Sushi-Yu]