°Lintner or degrees Lintner (per pound of grain) is a unit used to measure the ability of a

malt Malt is germinated cereal grain that has been dried in a process known as " malting". The grain is made to germinate by soaking in water and is then halted from germinating further by drying with hot air. Malted grain is used to make beer, ...

to reduce

starch Starch or amylum is a polymeric carbohydrate consisting of numerous glucose units joined by glycosidic bonds. This polysaccharide is produced by most green plants for energy storage. Worldwide, it is the most common carbohydrate in human diets ...

to sugar, that is, its

diastatic power Mash ingredients, mash bill, mashbill, or grain bill are the materials that brewers use to produce the wort that they then ferment into alcohol. Mashing is the act of creating and extracting fermentable and non-fermentable sugars and flavor c ...

. While the measurement is applicable to any

amylase An amylase () is an enzyme that catalyses the hydrolysis of starch (Latin ') into sugars. Amylase is present in the saliva of humans and some other mammals, where it begins the chemical process of digestion. Foods that contain large amount ...

, in general it refers to the combined

α-amylase α-Amylase is an enzyme (EC 3.2.1.1; systematic name 4-α-D-glucan glucanohydrolase) that hydrolyses α bonds of large, α-linked polysaccharides, such as starch and glycogen, yielding shorter chains thereof, dextrins, and maltose: :Endohydr ...

and

β-amylase β-Amylase (EC 3.2.1.2 , saccharogen amylase, glycogenase) is an enzyme with the systematic name ''4-α-D-glucan maltohydrolase''. It catalyses the following reaction: : Hydrolysis of (1→4)-α-D-glucosidic linkages in polysaccharides so as to ...

used in

brewing Brewing is the production of beer by steeping a starch source (commonly cereal grains, the most popular of which is barley) in water and fermenting the resulting sweet liquid with yeast. It may be done in a brewery by a commercial brewer, ...

. The term is also generalized to diastatic

malt extract Malt is germinated cereal grain that has been dried in a process known as "malting". The grain is made to germinate by soaking in water and is then halted from germinating further by drying with hot air. Malted grain is used to make beer, whi ...

s and separately prepared brewing enzymes. The abbreviation °L is official, but in brewing applications it may conflict with °L used for

degrees Lovibond When drinking beer, there are many factors to be considered. Principal among them are bitterness, the variety of flavours present in the beverage and their intensity, alcohol content, and colour. Standards for those characteristics allow a more o ...

. JECFA, the

Joint FAO/WHO Expert Committee on Food Additives The Joint FAO/WHO Expert Committee on Food Additives (JECFA) is an international scientific expert committee that is administered jointly by the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO). ...

, defines the degree Lintner as follows: :''A malt has a diastatic power of 100 °L if 0.1 cc of a clear 5% infusion of the malt, acting on 100cc of a 2%

solution at 20°C for one

hour An hour (symbol: h; also abbreviated hr) is a unit of time conventionally reckoned as of a day and scientifically reckoned between 3,599 and 3,601 seconds, depending on the speed of Earth's rotation. There are 60 minutes in an hour, and 24 ho ...

, produces sufficient reducing sugars to reduce completely 5cc of

Fehling's solution In organic chemistry, Fehling's solution is a chemical reagent used to differentiate between water-soluble carbohydrate and ketone () functional groups, and as a test for reducing sugars and non-reducing sugars, supplementary to the Tollens' re ...

.'' Note that the amylases used in brewing reach their peak efficiencies around 66 °C. Evaluation of a malt or extract is usually done by the manufacturer rather than by the end user; as a rule of thumb, the total

grain bill Mash ingredients, mash bill, mashbill, or grain bill are the materials that brewers use to produce the wort that they then ferment into alcohol. Mashing is the act of creating and extracting fermentable and non-fermentable sugars and flavor ...

of a mash should have a diastatic power of at least 40 °L in order to guarantee efficient conversion of all the starches in the mash to sugars. The most active

barley Barley (''Hordeum vulgare''), a member of the grass family, is a major cereal grain grown in temperate climates globally. It was one of the first cultivated grains, particularly in Eurasia as early as 10,000 years ago. Globally 70% of barley ...

malts currently available have a diastatic activity of 110 - 160 °Lintner (385 - 520 °WK). In Europe, diastatic activity is often stated in

Windisch–Kolbach unit °WK or degrees Windisch-Kolbach is a unit for measuring the diastatic power of malt, named after the German brewer Wilhelm Windisch and the Luxembourg brewer Paul Kolbach. It is a common unit in beer brewing (especially in Europe) that measur ...

s (°WK). These are related approximately to °Lintner by: :

^\circ\mbox = \frac

^\circ\mbox = \left ( 3.5 \times ^\circ\mbox{Lintner} \right ) - 16

. 100.0 °Lintner equals 3.014 × 10⁻⁷

katal The katal (symbol: kat) is the unit of catalytic activity in the International System of Units (SI) used for quantifying the catalytic activity of enzymes (that is, measuring the enzymatic activity level in enzyme catalysis) and other catal ...

or 18.08

enzyme unit The enzyme unit, or international unit for enzyme (symbol U, sometimes also IU) is a unit of enzyme's catalytic activity. 1 U (μmol/min) is defined as the amount of the enzyme that catalyzes the conversion of one micro mole of substrate per mi ...

References

External links

"Malt Carbohydrase", JECFA, 1971.
Gives definitions and procedures for measuring diastatic activity. Brewing Units of catalytic activity