The text provides information about the origins and preparation methods associated with traditional sushi dishes.

According to the passage:

1. The rice used for sushi typically consists of Japonica variety, which is starchy.

2. Sushi rice differs from other types of rice due to its medium-grain size and rounded shape.

3. Regardless of the toppings or fillings involved, all forms of sushi always include this specific type of rice.

The term 'sushi' itself originates from Japanese words:

- 'Su' means 'vinegar'

- 'Shi' comes from 'meshi', which is the Japanese word for 'rice'

Therefore, when combined, the phrase literally translates to mean 'vinegared rice'. The primary characteristic associated with this dish lies in its sour flavour derived from being vinegated.

Historically speaking:

1. Initially, sushi was not primarily a food item but rather an ancient method of preserving fish through fermentation.

2. This practice involved placing raw or cured fish inside layers of short-grained white rice and allowing it to ferment over time.

3. The process allowed people in Southeast Asia, where this dish is believed to have originated from more than 2000 years ago, to extend the shelf life of their catch.

Over centuries, as food preservation techniques improved:

1. People began using vinegar instead of salt or other seasonings for fermentation, which resulted in a milder flavour.

2. Eventually, raw fish was introduced as an alternative to cured fish, and consumers started consuming both the rice and fish together.

3. This marked the birth of modern sushi as we know it today.

To sum up, sushi has evolved from its origins as a means of preserving food into a popular Japanese dish that typically consists of vinegared rice served with various types of fish or seafood.

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