The vocabulary of brewing can quickly make your head spin. Here’s a lexicon of the main terms — from ingredients to styles, by way of tasting — to consult as you read.
A
Alcoholic fermentation — The transformation of sugars into alcohol under the action of enzymes of yeast or bacterial origin, in the absence of oxygen. It also produces carbon dioxide (CO₂) and various aromatic compounds.
Ale — A top-fermented beer. Along with lambics and lagers, ales form one of the three great families of beer. In Belgium the term evokes top-fermented beers of English influence: a copper colour, moderate alcohol (~5%), a malty sweetness with biscuity notes, light bitterness, a fruity and faintly spicy aroma. “Everyday” beers. Examples: Vieux-Temps, De Koninck, Palm.
Alpha acids — Made up of humulone, cohumulone and adhumulone, these are the bitter resins of hops. Poorly soluble, barely volatile and naturally bitter, they must be isomerised by heat to become soluble in the wort. It’s their level that determines a hop’s bitterness: the higher the concentration, the more bitterness the hop brings.
B
Barley — An annual grass whose seeds, used in the form of malt, serve to make beer. Two-row spring barley is preferred to six-row winter barley. Climate and terroir influence the flavour of the beer.
Barley wine — Literally “wine of barley”. A very strong beer (8 to 12%), top-fermented, full-bodied with a fruity bouquet. Bottle-conditioned, it withstands long cellar maturation and improves over the years.
Beer — An alcoholic drink obtained by yeast fermentation of an infusion of cereals, based on water, malt and hops. Since Antiquity and across every civilisation, a popular, festive and nourishing drink.
Beer colour — It varies with the malts used and is measured in EBC (European Brewing Convention). A blonde sits between 6 and 12 EBC, an amber between 13 and 30 EBC; from 60 EBC, the beer is black.
Bitterness — The characteristic sensation felt on the palate, caused by the iso-alpha acids from the hops. For comparison, you meet this bitterness when you bite into the white pith of a grapefruit.
Bottom fermentation — Yeasts are added to wort cooled to 10 °C. Fermentation lasts several weeks, between 8 and 12 °C, and leaves room for the aromas of malt and hops. The generic term “lager” designates these beers.
Brettanomyces — Wild yeasts present in the air, at work in spontaneously fermented beers. After several years of maturation, they impart a fruitiness (apple, lemon) and complex scents (wet leather, farmyard, earth, hay).
Brew — The volume of wort produced in one brewing session. It’s usually the size of the mash tun that sets it. The baker has their batch, the brewer their brew — and they have every interest in doing several a day to cut their fixed costs.
Brewer — The person in charge of making the beer. They must have full command of their brewery’s particular process to ensure consistent quality.
Brewery — A facility equipped for the various stages of making beer. Bottling is sometimes done elsewhere.
D
Double / Dubbel — A name used for abbey or Trappist beers. By playing on the malts, the brewer obtains a russet or brown colour and an alcohol of 6 to 8%. Soft, malty beers, rich and complex, with notes of raisins, prunes, banana, caramel and rose.
Dry hopping (cold hopping) — Once the alcoholic fermentation is over, the brewer adds hops (1 to 2 g/L) to the young beer. As the infusion happens cold, it brings no bitterness, but the essential oils of the hop — usually lost in the boil — diffuse thanks to the alcohol. After 2 to 3 weeks the hops are removed: the beer is highly aromatic, with intense hoppy notes.
H
Haze — A feature of unfiltered, bottle-conditioned beers. It’s caused by fine organic particles (proteins, yeast, hop resins) naturally held in suspension in the beer.
Head — It depends above all on the presence of CO₂ bubbles. This gas is produced and dissolved naturally during fermentation (it can also be injected). Its quality — stability, texture, bubble size — depends on the raw materials and the brewing process. The glass matters too: its shape, its cleanliness and the tiny imperfections of its inner surface all influence the head.
Hops — A perennial climbing plant of the Cannabaceae family. Its flowers, little cones of leaflets, shelter tiny yellow glands of lupulin, which hold bitter resins and essential oils. Hops bring aromas and bitterness; thanks to their tannins, they also act as a natural preservative and clarifier.
L
Lambic — A spontaneously fermented beer, aged in oak casks for 1 to 3 years, which gives it a sour taste and complex aromas. Little or not at all sparkling, it’s produced naturally in the Pajottenland, south-west of Brussels.
Lees — The yeast deposit: the build-up of yeast at the bottom of a tank or a bottle.
M
Malt — Obtained from cereals (most often barley). At the maltings, the grains are made to germinate then dried in hot air. A portion serves to make special malts, more or less coloured, caramelised or roasted. By combining them in varying proportions, the brewer achieves the colour and flavour sought. Malt holds the starch which, turned into sugars during the mash, is then converted into alcohol during fermentation.
O
Off-flavour — A tasting term for a sensory defect, the result of poor control of the process. The most common: smells of apple, plastic, clove, paint, vinegar, detergent, cooked vegetable, onion, wet sock.
Oxidation — Probably the most common defect. At bottling or kegging, the uptake of oxygen is to be avoided: the beer risks developing a wet-cardboard taste. In some cases, a “madeirisation” instead brings a complexity prized by enthusiasts.
P
Plato (degree) — A unit of measurement for wort density (written °P), expressing the percentage of extract by weight. 1 °Plato equals 10 g of sugar per kilo of wort. Handy, because the brewer then knows directly the amount of potentially fermentable sugar.
S
Saison — A top-fermented beer, moderately alcoholic, blonde to amber in colour. Well hopped, with fruity aromas and a dry finish, sometimes slightly sour. A refreshing summer beer born in the farmhouse breweries of Hainaut, where it was brewed in winter to quench the thirst of farm workers in summer.
Spéciale Belge — A top-fermented beer created by Belgian brewers in the early 20th century to compete with German Pils: amber, malty, with pronounced hopping (~5%). Today the term “bière spéciale” covers many Belgian beers with a particular brew or an original ingredient.
Spontaneous fermentation — After cooling, the wort is left in contact with the ambient air for several hours to take on wild yeasts and bacteria. These beers — the “lambics” — are brewed in winter and fermented in oak tuns. The result: tart, complex beers.
Stout — A style of the ale family, of English origin, successor to the Porter. Brewed with a portion of roasted barley grains, hence its black colour and its coffee aromas. The bitterness, clearly present, contributes to the balance. Many variants: sweet (or milk) stout, dry (or bitter) stout, oatmeal stout, foreign extra (or export) stout, imperial (or Russian) stout.
Strong blonde — A category in its own right (7.5 to 10.5%), almost exclusively Belgian, created after the Second World War to rival Pils. Top-fermented, a clear golden colour, a compact head, fine effervescence. Often bottle-conditioned, they give off complex aromas, fruity and slightly spicy. Today they’re distinguished from Triples, though the two styles are close.
T
Top fermentation — Yeasts are added to wort cooled to 20 °C. Fermentation lasts a few days, between 15 and 25 °C, and releases complex, fruity aromas. The generic term “ale” designates these beers.
W
Water — It may seem obvious, but beer is 90% water. Its quality is crucial: it influences the brewing and the fermentation, and shapes the colour, the nutritional qualities and the flavour of the beer.
Wheat — A cereal used for certain beers, including witbier. Added as raw grains, malted grains or flakes, rich in proteins, it brings body, a natural haze and a light, refreshing acidity.
Witbier — Brewed in equal parts with barley malt and raw wheat, often flavoured with spices (ground coriander, bitter orange peel). Unfiltered, it stands out for its natural haze and its slightly tart taste. Lightly alcoholic (4.5 to 5.5%), it’s a refreshing summer beer, brought back into fashion in the 1960s by Pierre Celis, creator of Hoegaarden witbier.
Wort — The sweet liquid obtained after lautering the cereal infusion. It’s then boiled with hops, then cooled to fermentation temperature, where the brewer adds the yeast.
Y
Yeast — Single-celled microscopic fungi that live and multiply by consuming sugars. In the absence of air, they turn these sugars into ethyl alcohol and carbon dioxide: fermentation. Along the way, they produce a host of aromatic substances that give beer its character.
