- Sweet, dry
Equivalent terms for the basic adjectives amai (甘い, sweet,) and karai (辛い, dry; the character 口 meaning mouth). The sweet taste of sake is largely derived from the glucose component of its extract content. The primary processes in the fermentation of sake moromi are the creation of glucose from rice starch by the action of koji-derived enzymes, and the conversion of that glucose to alcohol by yeast. Sake containing a large quantity of unconverted glucose is sweet, whereas that in which the yeast has consumed large quantities of glucose, leaving little behind, becomes dry.
However, between the time of pressing and pasteurization (hi-ire), the amount of glucose can increase due to the breakdown of disaccharides, polysaccharides and dextrin, so its content can change according to the timing of pasteurization. Moreover, sake with identical glucose content tastes less sweet the greater its organic acid content, so it is not possible to judge how sweet or dry a sake is by glucose content alone.
Recently a new scale for measuring sweet and dry (the shin amakara-do(新甘辛度, “new amakara scale”), based on the percentage of glucose and the acidity (san-do) in millilitres, has been developed. The glucose concentration and acidity are calculated at two decimal places (rounded up), and the resulting values expressed as follows.
Dry: shin amakarado ≦0.2
Slightly dry: 0.3≦ shin amakarado ≦1.0
Slightly sweet: 1.1≦ shin amakarado ≦1.8
Sweet: 1.9≦ shin amakarado