What does the term 'kasu' refer to in sake brewing?

The term 'kasu' specifically refers to sake lees, which are the leftover solids that remain after the sake has been pressed from the fermented rice mash (known as 'moromi'). Sake lees consist primarily of rice particles, dead yeast, and other components that were part of the fermentation process.

Kasu plays a crucial role in sake brewing as it is a byproduct that can be utilized in various culinary applications. It has its own distinct flavor and nutritional properties, making it popular in traditional Japanese cooking for marinades, sauces, and soups. Additionally, it can be further processed to create products such as kasu sake or even incorporated into skin care products due to its beneficial qualities.

Understanding this term and its implications in both sake production and culinary possibilities highlights its significance in the overall context of sake and Japanese cuisine.