Barm, also called ale yeast, is the foam or scum formed on the top of a fermenting liquid, such as

beer Beer is an alcoholic beverage produced by the brewing and fermentation of starches from cereal grain—most commonly malted barley, although wheat, maize (corn), rice, and oats are also used. The grain is mashed to convert starch in the ...

wine Wine is an alcoholic drink made from Fermentation in winemaking, fermented fruit. Yeast in winemaking, Yeast consumes the sugar in the fruit and converts it to ethanol and carbon dioxide, releasing heat in the process. Wine is most often made f ...

, or feedstock for spirits or industrial

ethanol Ethanol (also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound with the chemical formula . It is an Alcohol (chemistry), alcohol, with its formula also written as , or EtOH, where Et is the ps ...

distillation Distillation, also classical distillation, is the process of separating the component substances of a liquid mixture of two or more chemically discrete substances; the separation process is realized by way of the selective boiling of the mixt ...

. It is used to

leaven In cooking, a leavening agent () or raising agent, also called a leaven () or leavener, is any one of a number of substances used in doughs and batter (cooking), batters that cause a Effervescence, foaming action (gas bubbles) that lightens and ...

bread Bread is a baked food product made from water, flour, and often yeast. It is a staple food across the world, particularly in Europe and the Middle East. Throughout recorded history and around the world, it has been an important part of many cu ...

, or set up fermentation in a new batch of liquor. Barm, as a leaven, has also been made from ground

millet Millets () are a highly varied group of small-seeded grasses, widely grown around the world as cereal crops or grains for fodder and human food. Most millets belong to the tribe Paniceae. Millets are important crops in the Semi-arid climate, ...

combined with

must Must is freshly crushed Juice, fruit juice (usually grape juice) that contains the skins, seeds, and stems of the fruit. The solid portion of the must is called pomace and typically makes up 7–23% of the total weight of the must. Making must ...

out of wine-tubs and is sometimes used in English baking as a synonym for a natural leaven (

sourdough Sourdough is a type of bread that uses the fermentation by naturally occurring yeast and lactobacillus bacteria to raise the dough. In addition to leavening the bread, the fermentation process produces lactic acid, which gives the bread its dis ...

). Reinhart derived the term from his training unde
Monica Spiller
Various cultures derived from barm, usually ''

Saccharomyces cerevisiae ''Saccharomyces cerevisiae'' () (brewer's yeast or baker's yeast) is a species of yeast (single-celled fungal microorganisms). The species has been instrumental in winemaking, baking, and brewing since ancient times. It is believed to have be ...

'', became ancestral to most forms of

brewer's yeast ''Saccharomyces cerevisiae'' () (brewer's yeast or baker's yeast) is a species of yeast (single-celled fungal microorganisms). The species has been instrumental in winemaking, baking, and brewing since ancient times. It is believed to have been o ...

and

baker's yeast Baker's yeast is the common name for the strains of yeast commonly used in baking bread and other bakery products, serving as a leavening agent which causes the bread to rise (expand and become lighter and softer) by converting the fermentable ...

currently on the market. A barm cake is a soft, round, flattish

bread roll A bread roll is a small, oblong individual loaf of bread served as a meal accompaniment (eaten plain or with butter). Rolls can be served and eaten whole or are also commonly cut and filled – the result of doing so is considered a '' sandwic ...

from

North West England North West England is one of nine official regions of England and consists of the ceremonial counties of England, ceremonial counties of Cheshire, Cumbria, Greater Manchester, Lancashire and Merseyside. The North West had a population of 7,4 ...

, traditionally

ed with barm. In

Ireland Ireland (, ; ; Ulster Scots dialect, Ulster-Scots: ) is an island in the North Atlantic Ocean, in Northwestern Europe. Geopolitically, the island is divided between the Republic of Ireland (officially Names of the Irish state, named Irelan ...

, barm is used in the traditional production of barmbrack, a fruited bread. Emptins, a homemade product similar to barm and usually made from

hops Hops are the flowers (also called seed cones or strobiles) of the hop plant ''Humulus lupulus'', a member of the Cannabaceae family of flowering plants. They are used primarily as a bittering, flavouring, and stability agent in beer, to whic ...

or potatoes and the dregs of cider or ale casks, was a common leavener for those living in rural areas far from a brewery, distillery, or bakery from which they could source barm or yeast.

References

Leavening agents {{ingredient-stub

See also

References