What does the term Nigori refer to in sake?

The term "Nigori" refers to roughly filtered sake, which is characterized by its cloudy appearance due to the presence of rice particles and yeast that have not been completely removed during the filtration process. This style of sake has a distinct texture and can offer a unique flavor profile that is often sweeter and creamier compared to clear sake. Nigori sake is typically unfiltered or lightly filtered, allowing the residual rice solids to contribute to its richness and body.

In contrast, the other terms do not align with the definition of Nigori. Highly polished sake (which involves a more refined milling process) results in clearer, more delicate flavors. Aged sake refers to sake that has been stored for a period of time, which can develop complexity but does not indicate the unfiltered nature of Nigori. Unfermented sake would not undergo the fermentation process necessary to convert rice into alcohol, which fundamentally differs from the characteristics of Nigori.