Japanese Sake Terminology Nihonshu-do Acidity Amino Acids

Japan — sake technical vocabulary developed systematically by the Brewing Society of Japan (Jozo Gakkai) during 20th century

Japanese sake quality and character is described through a vocabulary of technical measurements that, when understood together, provide a complete flavour map of any given bottle. The three most important parameters are nihonshu-do (日本酒度, sake meter value or SMV), san-do (酸度, acidity), and amino-san-do (アミノ酸度, amino acid content). Nihonshu-do measures the specific gravity of sake relative to water on a scale where 0 is neutral, positive values are dry, and negative values are sweet — most modern premium sake falls between -3 (sweet) and +7 (dry). San-do measures the total organic acid content (lactic, malic, succinic acids) on a scale from 0.9 to 2.2+ — higher acidity produces sharper, more food-complementary sake; lower acidity creates rounder, gentler profiles. Amino-san-do (typically 0.5–2.5) measures glutamic acid and other amino acids that contribute umami, body, and richness — higher values create savouriness and weight; lower values produce cleaner, thinner profiles. The interplay of these three measures determines the overall impression: a sake with high nihonshu-do (dry), high san-do (acidic), and low amino acids is lean, sharp, and refreshing; high nihonshu-do with low acidity and high amino acids is dry but rich and savoury. Beyond these three, ginjo-ka describes the fruity ester aromatics of cold-fermented ginjo and daiginjo, while nama (unpasteurised) indicates freshness and slightly wild character. Tokubetsu (special), junmai (pure rice, no added alcohol), and honjozo (small amount of brewer's alcohol added) describe production categories, not flavour directly.

Conceptual framework — nihonshu-do, san-do, and amino-san-do together predict the sensory experience: dry, lean and sharp versus rich, savoury, and round