The bones of Buddha are called “Butsu shari” which translates literally to “Buddha’s ashes”. Although there are a variety of theories, rice was first called “shari” because it resembles bones both in color and shape.
Cooked rice mixed with sushi-vinegar in which sugar and salt are added. In sushi term, it is called “shari (sushi rice or vinegared rice)”. It is said that fish ingredient counts up 40% and shari is responsible for 60% to make tasty sushi. Bad-taste shari spoils entire sushi even if a good fish ingredient is used.
Then when you put the sushi in your mouth and bite down, it should ideally come apart to fill your mouth easily, the shari should have harmonious synergy with the topping, and it should pass down your throat smoothly. The right temperature for sushi is around skin temperature, so that the chef can make it comfortably.
The flavoring of shari differs between Kanto (the East) and Kansai (the West). In Kansai, there tends to be more sugar used for a sweeter seasoning to bring out the flavor of shiromi. In Kanto, a lot of akami is eaten so very little (or no) sugar is used, and instead, the focus is on utilizing the acidity of the vinegar. “Akazu”, which is made by maturing sake lees for a long period of time, was available at a cheap price during the Edo period, so it was the standard for Edo-style sushi at the time. Due to the mild acidity and unique body and flavor, more and more young sushi chefs have started using akazu again.
Furthermore, each restaurant chooses rice based on whether the glutinous, sweetness, kernel size and firmness will be suitable for the shari or not. Generally, the first crop of the year tends to be more glutinous, so it is avoided, but the chef makes original shari by using rice matured at low temperatures, blending different rices, etc. The shari you enjoy is the result of the chef’s experience and pursuit for excellence in type, composition, steaming method, etc.