°Lintner or degrees Lintner is a unit used to measure the ability of a malt to reduce starch to sugar, that is, its diastatic power.
While the measurement is applicable to any amylase, in general it refers to the combined α-amylase and β-amylase used in brewing.
The term is also generalized to diastatic malt extracts and separately prepared brewing enzymes.
JECFA, the Joint FAO/WHO Expert Committee on Food Additives, defines the degree Lintner as follows: Note that the amylases used in brewing reach their peak efficiencies around 66 °C.
Maltose, the main sugar produced in mashing, is a disaccharide of glucose with one reducing equivalent (one reactive aldehyde group).