A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

Adjunct

Any non-enzymatic fermentable. Adjuncts include: unmalted cereals such as flaked barley or corn grits, syrups, and sugars.

Aerate

To mix air into solution to provide oxygen for the yeast.

Aerobic

A process that utilizes oxygen.

Aldehyde

A chemical precursor to alcohol. In some cases, alcohol can be oxidized to aldehydes, creating off-flavors.

Ale

A beer brewed from a top-fermenting yeast with a relatively short, warm fermentation.

Aleurone Layer

The living sheath surrounding the endosperm of a barley corn, containing enzymes.

Alkalinity

The condition of pH between 7-14. The chief cause of alkalinity in brewing water is the bicarbonate ion (HCO3-1).

Alpha Acid Units (AAU)

A home brewing measurement of hops. Equal to the weight in ounces multiplied by the percent of alpha acids.

Amino Acids

An essential building block of protein, being comprised of an organic acid containing an amine group (NH2).

Amylase

An enzyme group that converts starches to sugars, consisting primarily of alpha and beta amylase, which is also referred to as the diastatic enzymes.

Amylopectin

A branched starch chain found in the endosperm of barley. It can be considered to be composed of amylose.

Amylose

A straight-chain starch molecule found in the endosperm of barley.

Anaerobic

A process that does not utilize oxygen or may require the absence of it.

Attenuation

The degree of conversion of sugar to alcohol and CO2.

Autolysis

When yeast run out of nutrients and die, they release their innards into the beer, producing off-flavors.Back to Top

Bacteria

Most of the intentional microbial activity is facilitated by yeast; however bacteria also play an influential role in beer production.

°Balling, °Brix, or °Plato

These three nearly identical units are the standard for the professional brewing industry for describing the amount of available extract as a weight percentage of cane sugar in solution, as opposed to specific gravity. Eg. 10 °Plato is equivalent to a specific gravity of 1.040.

Beer

Any beverage made by fermenting a wort made from malted barley and seasoned with hops.

Beerstone

A hard organo-metallic scales that deposits on fermentation equipment; chiefly composed of calcium oxalate.

Biotin

A colorless crystalline vitamin of the B complex, found especially in yeast, liver, and egg yolk.

Blending

We commonly blend beers that are in different barrels or produced at different times to ensure we have a consistent beer or achieve a flavor we desire.

Blow-off

A type of airlock arrangement consisting of a tube exiting from the fermenter, submerging into a bucket of water, that allows the release of carbon dioxide and removal of excess fermentation material.

Buffer

A chemical species, such as a salt, that by disassociation or re-association stabilizes the pH of a solution.Back to Top

Carmelization

Is a chemical process that takes place when sugar is heated to a high temperature. In this process, sugar is broken down in a complex series of chemical reactions. This causes the sugar to gradually pick up a brown color and makes its flavor much more complex.

Cellulose

Similar to a starch, but organized in a mirror aspect; cellulose cannot be broken down by starch enzymes, and vice versa.

Cold Break

Proteins that coagulate and fall out of solution when the wort is rapidly cooled prior to pitching the yeast.

Conditioning

An aspect of secondary fermentation in which the yeast refine the flavors of the final beer. Conditioning continues in the bottle.Back to Top

Decoction

A method of mashing wherein temperature rests are achieved by boiling a part of the mash and returning it to the mash tun.

Decoction Mash

During the mash in process, decoction mash is a type of mash in which the various mash temperatures are achieved by removing part of the mash, boiling it in a separate vessel, and then using it as infusion water to heat the remainder of the mash. It is traditional in many continental European beer styles, especially in Germany and the Czech Republic.

Dextrin

A complex sugar molecule, left over from diastatic enzyme action on starch.

Dextrose

Equivalent to Glucose, but with a mirror-image molecular structure.

Diastatic Power

The amount of diastatic enzyme potential that a malt contains.

Dimethyl Sulfide (DMS)

A background flavor compound that is desirable in low amounts in lagers, but that at high concentrations tastes of cooked vegetables.Back to Top

Endosperm

The nutritive tissue of a seed, consisting of carbohydrates, proteins, and lipids.

Enzymes

Protein-based catalysts that effect specific biochemical reactions.

Esters

Aromatic compounds formed from alcohols by yeast action. Typically smell fruity.

Ethanol

The type of alcohol in beer formed by yeast from malt sugars.

Extraction

The soluble material derived from barley malt and adjuncts. Not necessarily fermentable.Back to Top

Fatty Acid

Any of numerous saturated or unsaturated aliphatic monocarboxylic acids, including many that occur in the form of esters or glycerides, in fats, waxes, and essential oils.

Fermentation

The total conversion of malt sugars to beer, defined here as three parts, adaptation, primary, and secondary.

Finings

Ingredients such as isinglass, bentonite, Irish moss, etc, that act to help the yeast to flocculate and settle out of finished beer.

Flocculation

To cause to group together. In the case of yeast, it is the clumping and settling of the yeast out of solution.

Fructose

Commonly known as fruit sugar, fructose differs from glucose by have a key tone group rather than an aldehydic carbonyl group attachment.

Funk

More and more brewers are experimenting with brettanomyces (Brett ) yeast. Yeast consumes the sugars and transforms them into alcohol. Brett creates a rustic, barnyard, distinctive flavor that brewers find it gives their beer that extra kick that the Belgians have had for years.

Fusel Alcohol

A group of higher molecular weight alcohols that esterify under normal conditions. When present after fermentation, fusels have sharp solvent-like flavors and are thought to be partly responsible for hangovers.Back to Top

Gelatinization

The process of rendering starches soluble in water by heat, or by a combination of heat and enzyme action, is called gelatinization.

Germination

Part of the malting process where the acrospire grows and begins to erupt from the hull.

Glucanase

An enzyme that acts on beta glucans, a type of gum found in the endosperm of unmalted barley, oatmeal, and wheat.

Glucose

The most basic unit of sugar. A single sugar molecule.

Gravity

Like density, gravity describes the concentration of malt sugar in the wort. The specific gravity of water is 1.000 at 59F. Typical beer worts range from 1.035-1.055 before fermentation (Original Gravity).

Grist

The term for crushed malt before mashing.Back to Top

Hardness

The hardness of water is equal to the concentration of dissolved calcium and magnesium ions. Usually expressed as ppm of (CaCO3).

Hopback

A vessel that is filled with hops to act as a filter for removing the break material from the finished wort.

Hops

Hop vines are grown in cool climates and brewers make use of the cone-like flowers. The dried cones are available in pellets, plugs, or whole.

Hot Break

Proteins that coagulate and fall out of solution during the wort boil.

Hot Water Extract

The international unit for the total soluble extract of a malt, based on specific gravity. HWE is measured as liter*degrees per kilogram, and is equivalent to points/pound/gallon (PPG) when you apply metric conversion factors for volume and weight. The combined conversion factor is 8.3454 X PPG = HWE.

Hydrolysis

The process of dissolution or decomposition of a chemical structure in water by chemical or biochemical means.Back to Top

Infusion

A mashing process where heating is accomplished via additions of boiling water.

International Bittering Units (IBU)

A more precise unit for measuring hops. Equal to the AAU multiplied by factors for percent utilization, wort volume and wort gravity.

Invert Sugar

A mixture of dextrose and fructose found in fruits or produced artificially by the inversion of sucrose (e.g. hydrolyzed cane sugar).

IPA

and Double IPA

Irish Moss

An emulsifying agent, Irish moss promotes break material formation and precipitation during the boil and upon cooling.

Isinglass

The clear swim bladders of a small fish, consisting mainly of the structural protein collagen, acts to absorb and precipitate yeast cells, via electrostatic binding.

Lactose

A nonfermentable sugar, lactose comes from milk and has historically been added to Stout, hence Milk Stout.

Lauter

To strain or separate. Lautering acts to separate the wort from grain via filtering and sparging.

Lipid

Any of various substances that are soluble in nonpolar organic solvents, and that include fats, waxes, phosphatides, cerebrosides, and related and derived compounds. Lipids, proteins, and carbohydrates compose the principal structural components of living cells.

Liquefaction

As alpha amylase breaks up the branched amylopectin molecules in the mash, the mash becomes less viscous and more fluid; hence the term liquefaction of the mash and alpha amylase being referred to as the liquefying enzyme.

Lupulin Glands

Small bright yellow nodes at the base of each of the hop petals, which contain the resins utilized by brewers.Back to Top

Krausen (kroy-zen)

Used to refer to the foamy head that builds on top of the beer during fermentation, which is also an advanced method of priming.Back to Top

Lager

A beer brewed from a bottom-fermenting yeast and given a long cool fermentation.

Lag Phase

The period of adaptation and rapid aerobic growth of yeast upon pitching to the wort. The lag time typically lasts from 2-12 hours.Back to Top

Maillard Reaction

A browning reaction caused by external heat wherein a sugar (glucose) and an amino acid form a complex, and this product has a role in various subsequent reactions that yield pigments and melanoidins.

Maltose

The preferred food of brewing yeast. Maltose consists of two glucose molecules joined by a 1-4 carbon bond.

Maltotriose

A sugar molecule made of three glucoses joined by 1-4 carbon bonds.

Mash

The hot water steeping process that promotes enzymatic breakdown of the grist into soluble, fermentable sugars.

Melanoidins

Strong flavor compounds produced by browning (Maillard) reactions.

Methanol

Also known as wood alcohol, methanol is poisonous and cannot be produced in any significant quantity by the beer making process.

Modification

An inclusive term for the degree of degradation and simplification of the endosperm and the carbohydrates, proteins, and lipids that comprise it.Back to Top

Pellicle

A protective layer that naturally forms on the top of beer fermented with "wild" yeasts such as brettanomyces. The layer protects against oxygen which would otherwise spoil the aging beer, turning it to vinegar.

Peptidase

A proteolytic enzyme which breaks up small proteins in the endosperm to form amino acids.

pH

A negative logarithmic scale (1-14) that measures the degree of acidity or alkalinity of a solution for which a value of 7 represents neutrality. A value of 1 is most acidic, a value of 14 is most alkaline.

Phenol, Polyphenol

A hydroxyl derivative of an aromatic hydrocarbon that causes medicinal flavors and is involved in staling reactions.

Pitching

Term for adding the yeast to the fermenter.

Points per Pound per Gallon (PPG)

The US home brewers unit for total soluble extract of malt, based on specific gravity. The unit describes the change in specific gravity (points) per pound of malt, when dissolved in a known volume of water (gallons). Can also be written as gallon*degrees per pound.

ppm

The abbreviation for parts per million and equivalent to milligrams per liter (mg/l). Most commonly used to express dissolved mineral concentrations in water.

Primary Fermentation

The initial fermentation activity marked by the evolution of carbon dioxide and Krausen. Most of the total attenuation occurs during this phase.

Priming

The method of adding a small amount of fermentable sugar prior to bottling to give the beer carbonation.

Protease

A proteolytic enzyme which breaks up large proteins in the endosperm that would cause haze in the beer.

Proteolysis

The degradation of proteins by proteolytic enzymes e.g. protease and peptidase.Back to Top

Racking

The careful siphoning of the beer away from the trub.Back to Top

Saccharification

The conversion of soluble starches to sugars via enzymatic action.

Sanitize

To reduce microbial contaminants to insignificant levels.

Secondary Fermentation

A period of settling and conditioning of the beer after primary fermentation and before bottling.

Sparge

To sprinkle, to rinse the grain bed during lautering.

Sterilize

To eliminate all forms of life, especially microorganisms, either by chemical or physical means.

Sterols

Any of various solid steroid alcohols widely distributed in plant and animal lipids.

Sucrose

This disaccharide consists of a fructose molecule joined with a glucose molecule. It is most readily available as cane sugar.Back to Top

Tannins

Astringent polyphenol compounds that can cause haze and/or join with large proteins to precipitate them from solution. Tannins are most commonly found in the grain husks and hop cone material.

Trub (trub or troob)

The sediment at the bottom of the fermenter consisting of hot and cold break material, hop bits, and dead yeast.Back to Top

Wort (wart or wert)

The malt-sugar solution that is boiled prior to fermentation.Back to Top

Zymurgy

The science of brewing and fermentation.