# Brewing/Appendix
## A

* adjuncts Sources of fermentable sugar other than barley. In extract brewing, any grain added is sometimes referred to as "adjunct". Some brewers refer to coloured malts as adjuncts.
* ale A style of beer that uses top fermenting yeast.
* alpha acid An insoluble resin found in hops that provides the bitter characteristic of beer. The alpha acids are converted to more soluble iso alpha acids during the wort boiling in the brewhouse stage of the process.
* amylase The enzyme produced in the barley during malting that is needed for the conversion of the malt starches in the mash to malt sugars.
* amylose The technical term for large straight starch chains of glucose molecules.
* amylopectin branched starch molecules.

## B

* back a brewhouse vessel, for example under-back or hop-back.
* brewing Brewing is a generic term used to describe the entire beer production process, however it is technically correct only to refer to the time from beginning the boil until pitching yeast as brewing.
* beta acid An bitter insoluble resin present in hops that is not considered to add noticeable bitterness.

## D

* dunkel German word for dark.

## E

* enzyme a biological catalyst that helps a chemical reaction to take place. An enzyme is a special type of protein and in brewing the enzymes are provided by the malt.
* ester a flavour compound produced by the yeast during fermentation that results in a beer with a fruity flavour. Esters are promoted by higher fermentation temperatures and lower pitching rates. Examples of esters are: ethyl hexanoate (red apple flavour), iso-amyl acetate (banana flavour - sought after in a Bavarian weizen) ethyl acetate (solvent flavour - an unwanted ester).
* extract the sugars (and to a lesser extent amino acids) recovered from the mash. There are various measures of extract, the most popular are degrees Plato (°P) or specific gravity (S.G.)

## F

* fermentation The process in which yeast converts fermentable sugars to alcohol, CO$_2$, and flavouring compounds.
* fermentable sugars The most common fermentable sugars in an all malt wort are glucose, maltose and maltotriose. Other commonly occurring fermentable sugars are sucrose and fructose.

## G

* grist Milled grain from which fermentable starches are obtained; usually barley malt and sometimes adjuncts.
* gyle Unfermented wort set aside to provide sugars to be used in natural carbonation by krausening.

## H

* hops Flower buds of the hop plant used to bitter beer and provide flavor and aroma characteristics.

## I

* IPA or India Pale Ale A style of ale beer that originated from the liberal use of hops as a preservative in English beer destined for the India colony.

## K

* krauesen (noun) A layer of foam and dead yeast that forms on the surface of the fermenting beer during the primary fermentation stage.
* krauesen (verb) A method by which unfermented gyle is added to fermented beer, originating from the same initial wort, to prime natural carbonation.

## L

* lager (noun) A style of beer that is produced using lower fermentaion temperatures and a special bottom fermenting yeast.
* lager (verb) A method of conditioning beer by storing carbonated beer at near freezing temperatures.
* lautering The process by which spent grist and/or hops are removed from wort.
* lauter tun A vessel for producing clear wort from the mash. The slotted false bottom holds back the husk material which acts as filter material to produce clear wort.

## M

* malt Grain that has be allowed to germinate, and then dried.
* mash A process by which fermentable sugars, starches, and other flavor characteristics are extracted from malted grains.
* mash tun a vessel for the mixing of the malt grist and mashing liquor, and for the conversion of the malt starch to malt sugars. In the traditional British mash tun (or a two vessel brewhouse), the vessel is also used for wort separation.

## P

* pitch A term used to describe the indroduction of yeast to fermentable wort.

## S

* sparge A hot water rinse of grist (mash) to remove additional extract during the lautering process.
* steep the immersion in water - barley is steeped before germination to increase the water content in the grain to get the germination process started.

## T

* tun a brewhouse vessel, for example Mash tun, Lauter tun

## U

* ullage The space between the surface of a contained liquid and the top of the container.
* under-back A vessel between the lauter tun and the wort kettle used to hold the wort until the wort kettle is available. Normally only found in commercial breweries where multiple brews are produced per day.

## W

* wort (pronounced "wert") The product of the brewhouse process - a liquid rich in fermentable barley sugars with the hop bitterness components and nitrogen for yeast growth. The growth medium for the yeast.

## Y

* yeast Microorganisms that are applied to the task of converting sugars to alcohol, CO$_2$, and flavouring compounds.

## Z

* zymurgy The science of using yeast for fermentation. Also a magazine published by the American Homebrewers Association.

## Other

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