Sushi Rice - Sushi Knowledge

Short grain only!

Sushi should really only be made using short grain Japonica rice from either Japan or California. Because sushi has been developed and refined in Japan over the course of centuries, using local ingredients, it is perhaps only natural that Japanese rice works best, although Californian rice also gives good results.
see Japanese glossary - Rice & Rice Products

How absorbing

Moreover, because the absorbency of rice varies according to age, it is also believed that very new rice does not make the best sushi rice, because it does not absorb liquid well, and therefore the rice does not properly take in the sushi vinegar. Thus, many sushi restaurants leave their new rice for two to three months before using.

The perfect strain

In the past there existed a number of varieties of rice that were considered particularly suitable to making sushi, thanks to their size, texture and absorbency. Nowadays, the increasing importance placed on disease resistance means that many of these are no longer grown, although the Koshi Hikari and Sasa Nishiki varieties are generally said to be well suited to sushi making.