Here is a useful glossary of terms used in the beer brewing process. Soon you’ll be throwing these around with your friends to compete over who makes the best ale!
Ale
A beer fermented with ale yeast (sometimes referred to as top-fermenting yeast because of the significant amount of activity on the top of the brew). Ale is normally fermented at temperatures above 16C.
Adjunct
Any fermentable sugar (cane sugar, dextrose, honey, etc.) added to the wort.
Attenuation
How far the yeast ferments the brew to final gravity.
Brewmaster
The person behind the beer.
Conditioning
Following full carbonation during secondary fermentation the beer continues to condition in the bottle, improving aroma and flavour, clearing the beer and making the yeast sediment more compact.
Dry Hopping
An addition of hops to the brew in the fermenting vessel, primarily imparting aroma to the finished beer. May be infused as a “hop tea” prior adding and may also be added very late into the serving vessel.
Dextrose
The equivalent to Glucose, but with a mirror-image molecular structure. Dextrose for home brewing is the shortened name for Dextrose Monohydrate, as it normally carries a water molecule.
Esters
Aromatic compounds formed from alcohols by yeast action. They typically smell fruity and are more common in ale rather than lager.
Ethanol
The type of alcohol in beer formed by yeast fermenting the sugars.
Fermentation
The action of yeast metabolising the sugars available in the wort, with the main bi-products being carbon dioxide and alcohol. Regardless of the yeast type (ale or lager), fermentation activity occurs throughout the brew.
Final Gravity
The specific gravity of the brew once the yeast has finished fermenting all the available sugars. FG is achieved once the specific gravity is stable over a couple of days.
Finings
Most commonly derived from gelatine, added around ¾ of the way through primary fermentation, to assist in clearing the brew. The addition of finings is an intrusive method which can increase the risk of spoilage. Delaying bottling for a couple of days after FG and extending the conditioning time will clear the brew just as effectively.
Flocculation
Once fermentation activity slows, the yeast clumps together and settles out of solution.
Fusel Alcohol
May be produced from very high temperature fermentation, fusels have sharp solvent-like aromas and flavours.
Glucose
One of the most basic units of sugar, a single sugar molecule.
Head retention
The beer’s ability to maintain foam.
Hops
Used to season beer in a similar manner to herbs in cooking. Primarily used for bittering the brew but also may be added for the purposes of flavour and aroma (see Late Hopping).
Hydrometer
A device (often made of glass) used to measure the specific gravity of a fluid normally by floating it in a sample tube and measuring where the fluid cuts across the scale.
International Bittering Unit (IBU)
The unit of measure for the amount of bitterness in the brew.
Krausen (kroyzen)
The foamy head formed on top of the brew in the early stages of fermentation.
Lactose
A non-fermentable, yet not very sweet, sugar. Lactose (derived from milk) may be added to Stout, for example, to increase residual sweetness.
Lager
A beer brewed from lager yeast (sometimes referred to as bottom-fermenting yeast because of the lack of activity on the top of the brew). Normally fermented below 16C then lagered (stored for an extended period) prior to carbonating and packaging.
Lag Phase
The period of adaptation and rapid aerobic growth of yeast upon pitching. The lag time typically lasts from 2-12 hours and is a time where nothing much appears to be happening.
Late Hopping
The addition of hops with, typically, 15mins or less of the boil remaining. Primarily for flavour and aroma with a small amount of bitterness (also see Dry Hopping).
Maltodextrin
A complex sugar with very little sweetness. Yeast does not ferment it completely, leaving more body (carbohydrate) in the brew.
Pitching
Term for adding the yeast to the brew. Sprinkle dry yeast and stir in liquid yeast.
Primary Fermentation
The initial fermentation, normally evident by krausen (and a scum ring), sediment (at the bottom of the fermenting vessel) and Carbon Dioxide. Most of the total attenuation occurs during this phase.
Priming
Adding a small amount of fermentable sugar prior to bottling to give the beer carbonation.
Racking
Transferring the brew from one vessel to another, normally with the intent of removing it from the sediment and other solids.
Sanitise
To reduce the amount of micro-organisms to a minimum, normally performed after cleaning the equipment, using a chemical sanitiser.
Secondary Fermentation
Fermenting the brew in a secondary pressure vessel, normally bottle or keg, with the addition of some priming sugar. This process carbonates the brew, giving it fizz.