Seiryu-buai (整粒歩合)
Seiryu-buai refers to one of the criteria of determining the state of rice and represents in percentage how many seiryu, that is, rice grains each having an ordered excellent shape are present in a specific amount of unmilled rice.
Seiryu
Seiryu refers to rice grains left after removing cracked rice grains, broken rice grains, dead rice grains, immature rice grains, other kinds of grains, etc., from rice grains. Especially, when seiryu-buai is used to refer to rice, a term, seiryu-mai is also used. There is a term having similar meaning, 'kanzen-mai' (complete rice).
Class of eating rice
As to eating rice, rice having 70% or higher seiryu-buai is classified as itto-mai (first-class rice), that having 60% or higher seiryu-buai is classified as nito-mai (second-class rice), and that having 45% or higher seiryu-buai is classified as santo-mai (third-class rice).
Classes of rice suitable for producing sake
As to the rice suitable for producing sake (saka-mai), rice having 90% or higher seiryu-buai is classified as tokujo-mai (special-excellent-class rice), that having 80% or higher seiryu-buai is classified as tokuto-mai (excellent-class rice), that having 70% or higher seiryu-buai is classified as itto-mai (first-class rice), and that having 60% or higher seiryu-buai is classified as nito-mai (second-class rice), and that having 45% or higher seiryu-buai is classified as santo-mai (third-class rice).