When most people think of sushi today, they imagine fresh fish, vinegared rice, and beautifully prepared nigiri. But sushi did not begin as a luxury food — or even as a dish centered on raw fish. Its origins go back centuries, when preserving fish was far more important than serving it fresh. Sushi Began as Preservation One of the earliest forms of sushi was narezushi, a method in which fish was salted, packed with cooked rice, and fermented for long periods of time. The rice