Rice and corn adjuncts contribute little or no soluble protein to the wort, while other adjunct materials, such as wheat and barley, have higher levels of soluble protein. Except for barley, adjuncts also contribute little or no polyphenolic substances. Adjuncts can be used to adjust fermentability of a wort. Adjuncts are often used for their flavor contribution. For example, rice has a very neutral aroma and taste, while corn tends to impart a fuller flavor to beer.
Wheat tends to impart a dryness to beer.
Semi-refined sugars add flavor to ales that has been described as imparting a luscious character. Adjuncts will also alter the carbohydrate and nitrogen ratio of the wort, thereby affecting for formation of byproducts, such as esters and higher alcohols. Adjuncts are used for color adjustment, as in the case with dark sugars. On the other hand, adjuncts such as rice and pure starches and sugars are used to dilute malt colors to produce lighter colored beers. Other adjuncts, low in protein, are used to improve colloidal stability since they will dilute the amount of potential haze-forming proteins.