In brewing, 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). This is often done with the intention of cutting costs, but sometimes also to create an additional feature, such as better foam retention, flavours or nutritional value or additives. Both solid and liquid adjuncts are commonly used. Definition 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 Germany 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, rice, oats, unmalted barley and rye. The use of ingredients as substitutes for the main starch source is where the term adjunct is most often used. Types of adjuncts and adjunct products Adjuncts can be broadly classified according to the physical form in which they are used into solids and liquid syrups. Solid adjuncts are either starchy adjuncts which need to be converted to simpler sugars, or solid sugar adjuncts which can be added after conversion. Solid starchy adjuncts are normally produced from cereals and are used in the form of flakes, grits, flour or purified starch and must be added before the mash tun to convert the starch into simple sugars which the yeast can use during fermentation. Cereals with a higher gelatinisation temperature than the standard mashing temperatures must be cooked in a cereal cooker to gelatinise the starch before adding to the mash. Solid sugar adjuncts include granulated sugar and glucose chips. Liquid adjuncts are either sucrose syrups or syrups from a grain (maize, rice or wheat), are added directly to the wort kettle and therefore can be used to reduce loading on the mash and lauter tun and effectively increase the brewhouse capacity. Liquid adjuncts may also be