Wine & Spirit Education Trust (WSET) Level 3 Award in Sake Practice Exam 2026 - Free Sake Practice Questions and Study Guide

The shinpaku, which is the central core of the rice grain, is primarily composed of starch, making it almost completely pure starch. This distinction is crucial in sake production, as the starch content significantly influences the fermentation process and the flavor profile of the final product. The concentration of starch in the shinpaku is what allows for more efficient conversion into sugars during the koji mold application and subsequent fermentation.

In contrast, the outer layers of the endosperm contain higher amounts of protein, lipids, and other compounds that are not as concentrated in the shinpaku. This composition difference plays a vital role in the overall quality of the sake, as a higher starch concentration leads to a smoother and more refined taste.