(GRAINS OR STARCH)
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.
Adjunct is a bit of a moot word in the brewing industry, and refers to the use of a non-traditional ingredient outside the usual malted barley, hops, water and yeast. Adjuncts can be the addition of fruits are sugars. In this section the category of adjuncts relate to grain or starches used as inexpensive substitute for the primary ingredient – Barley.
Adjuncts are available in a variety of forms. They are most commonly found whole, torrified, flaked, or rolled, in meal or in starch/flour. The characteristics of each grain can vary depending on its milled form.
Whole grains: Often called “berries” (rye berries, wheat berries, and so forth), whole grains are the least processed form of adjunct.
Raw and Unmalted: Grains that have not undergone the malting process.
Grits and meal: Grits and meals are prepared by removing the hull and the germ from the kernel, then grinding the product to the desired fineness. This processing saves the brewer the step of cracking the grains, but grits and meals still require double mashing.
Flour: Flours are produced as by-products, during the manufacture of corn and rice. Flours must be cooked before being mixed in with the malt mash.
Groats: Groats are the hulled kernels of cereal grains such as oat, wheat, and rye. Groats are whole grains that include the cereal germ and fiber-rich bran portion of the grain as well as the endosperm.
Starch: Starches can be prepared from many cereal grains. In commercial practice, refined wheat starch, potato starch, and corn starch have been used in breweries; corn starches, in particular, are used in the preparation of glucose syrups. Wheat starch has been employed in breweries in Australia and Canada, where local conditions make it economical to use. However, the most important source of refined starch is corn.
Flaked and rolled grains: There are two different manufacturing processes used to produce brewing flakes. In the traditional process, corn and rice grits or whole barley are steam-cooked to soften the endosperm, which is then rolled flat and dried. Gelatinization occurs during the steaming process. Another process involves “micronizing” these materials prior to flaking by subjecting the grain to internal heating by infrared heat.
Torrefied grains: Produced by heating the grain quickly to 500 °F (260 °C), which makes the endosperm expand and pop, thus rendering the starch pre-gelatinized and easily milled. Once torrefied, grains can be added directly to the mash tun since the starch granules have been gelatinized. Most of the nitrogen is denatured in the kernel and is not solubilized, thus contributing little or no nitrogen to the mash.