Adjuncts

Adjuncts are unmalted grains (such as corn, rice, rye, oats, barley, and wheat) or grain products used in brewing beer which supplement the main mash ingredient (such as malted barley), often with the intention of cutting costs, but sometimes to create an additional feature, such as better foam retention, flavours or nutritional value or additives. Both solid and liquid adjuncts are commonly used, as well as spices.

Ingredients which are standard for certain beers, such as wheat in a wheat beer, may be termed adjuncts when used in beers which could be made without them — such as adding wheat to a pale ale for the purpose of creating a lasting head. The sense here is that the ingredient is additional and strictly unnecessary, though it may be beneficial and attractive. Under the Bavarian Reinheitsgebot purity law it would be considered that an adjunct is any beer ingredient other than water, barley, hops, and yeast; this, however, is an antiquated view. This purity law originated in 16th-century German and did not initially include yeast due to the fact that it had not been discovered yet.

The term adjunct is often used to refer to corn and rice, the two adjuncts commonly used by pale lager brewing companies as substitutes for barley malt. This use of ingredients as substitutes for the main starch source, (to lower the cost of production or lighten the body) is where the term adjunct is most often used.

Adjuncts can be broadly classified according to the physical form in which they are used into solids and liquid syrups.

Barley is used as an un-malted grain at up to 10% of the grist. Barley provides both carbohydrates and proteins to the wort, on the negative side the cell walls of the un-malted barley contain high levels of beta-glucans impacts on wort viscosity and haze problems in the bright beer. Barley is also used in the mash as roasted barley to provide colour to the beer.

Cassava is a novel adjunct used in Africa either as a wet cake or as a purified starch.

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