Brewing with Starchy Adjuncts: Its Influence on the Sensory and Nutritional Properties of Beer

Abstract

In brewing, the use of cereals (wheat, barley, maize, rice, sorghum, oats, rye or millet), pseudo-cereals (buckwheat, quinoa or amaranth) and tubers (sweet potato), as starch adjuncts, is being promoted for the production of a variety of high-quality beers, from sensory and nutritional points of view. The sensory properties of the obtained beer depend on the characteristics of each adjunct but also on the forms in which the adjunct is added: whole cereal, grits, malted, extruded grains, torrefied and syrup. Among these common forms, the extruded grains (maize or rice) produce a higher content of aroma compounds in beer. From a nutritional point of view, the use of non-conventional starch adjuncts, such as black rice, buckwheat or sweet potato, leads to an increase in the polyphenol content of the beer, and thus, its antioxidant capacity. Cereals such as maize, rice, sorghum or millet are the most promising for the production of gluten-free beers. A close relationship can be developed between the use of adjuncts in the beer industry and the use of commercial enzymes. Advances made by biotechnology to design new enzymes with different functionalities could be associated to a future increase in adjunct usage in brewing.

Buckwheat and Amaranth as Raw Materials for Brewing, a Review

“…Buckwheat is recognized as a good source of high biological value proteins that do not form gluten and a balanced amino acid composition (high levels of lysine and arginine, compared to cereals), lipids, antioxidants, organic acids, dietary fibre, mineral substances, and vitamins [ 2 , 25 , 41 , 42 , 73 ].…”

“…There is little information in the literature on the use of amaranth as a raw material in the beer industry, but its use as an unmalted adjuvant can be considered an innovation that will attract consumer interest [ 25 , 45 ].…”

“…Adding a small amount of unmalted amaranth, due to its nutritional and sensory properties, can contribute to the qualities of the finished product, in addition to enriching the beer wort with metal ions essential for the multiplication of yeasts in the fermentation process. According to Cadenas et al, 2021 [ 25 ], the use of amaranth as an adjunct in brewing increased the ratio of Mg 2+ /Ca 2+ , necessary for the efficient transformation of fermentable carbohydrates from beer wort into ethyl alcohol, as well as the content of Zn 2+ and Mg 2+ , even at an amount of 10% amaranth used in the manufacturing recipe.…”

“…In recent years, studies investigating the use of 100% alternative ingredients instead of barley malt in gluten-free beer production have increased [ 24 ]. Raw materials that have been investigated for making gluten-free beer include cereals such as sorghum, maize, rice, and millet, and pseudocereals such as buckwheat, amaranth, and quinoa [ 24 , 25 , 26 , 27 ]. However, techniques for producing beer from cereals (other than barley and wheat) and pseudocereals are not yet well developed.…”

“…Constant consumption of buckwheat can prevent some “diseases of the civilization born of food” (indigestion, obesity, constipation, cholesterol, diabetes, hypertension, etc.) [ 25 ]. Buckwheat is currently attracting increasing interest as a raw material for functional foods and pharmaceuticals [ 1 ].…”