Pushing boundaries in brewing by using 100% alternative unmalted cereals and exogenous enzymes

Barley malt, the traditional raw material for beer production, faces challenges from climate change, including declining yields and quality. Additionally, consumer demand for more diverse, sustainable, and functional beers has increased. To combat these challenges, the use of alternative unmalted cereals has gained increased interest among breweries in recent years. However, much research on unmalted brewing has focused on barley, and little is known about alternative cereals and pseudocereals. Therefore, small-scale mashing experiments with exogenous enzymes were conducted on 11 unmalted cereals and pseudocereals (two- and six-row barley, wheat, khorasan, spelt, sorghum, einkorn, tritordeum, triticale, buckwheat, and rye). Preliminary mashing experiments with 100% unmalted barley were conducted to evaluate key parameters influencing wort quality, such as pH, milling size, and enzyme dosage. A lower pH primarily improved filtration, while finer milling improved filtration speed, increased original gravity, free amino nitrogen (FAN), and soluble high molecular weight (HMW) proteins in the wort. Higher enzyme dosages benefited filtration and FAN content and slightly lowered soluble HMW proteins. In further experiments, the effects of pH and milling size were evaluated for 100% unmalted alternative cereals and pseudocereals and custom enzyme blends. Filtration was significantly improved by a low pH and fine milling for wheat, khorasan, and spelt, but not so much for tritordeum, triticale, einkorn, and sorghum. Preliminary results for buckwheat and rye showed poor filtration related to viscosity. Triticum-related cereals showed good original gravities and FAN contents, except einkorn, but with increased soluble HMW proteins. Sorghum showed the lowest original gravity and FAN content. Sugar analysis showed high amounts of fermentable sugars, and that sugar composition was influenced by the enzyme blend. Overall, mashing with 100% unmalted alternative cereals and exogenous enzymes proved successful. Further experiments on a 20 L scale should validate these findings and highlight possible challenges related to scale-up