In response to increasing consumer demand for new beer flavours and styles, this project investigated the applicability of unmalted alternative cereals and pseudocereals. It explored how brewers can implement these alternative raw materials into the brewing process. This involved scaling up from lab to industrial scale. The impact on the flavour, quality and stability of the innovative beers was examined.
The alternative cereals that were investigated are the ancient wheat varieties einkorn, emmer wheat, spelt and khorasan; the pseudocereals quinoa, amaranth and buckwheat, and other less common cereals such as sorghum, teff and tritordeum.
The cereals were characterised by macronutrient (carbohydrate, protein and fat), micronutrient (metal ions and beta-glucans) and enzymatic (diastatic power, alfa-amylase and beta-amylase) composition. Particle size distribution after grinding, gelatinisation temperature, general flavour profiling, and aldehyde content were determined.
Brewing with 40% of the unmalted cereals and pseudocereals was developed on an experimental scale, incorporating a pregelatinisation step when necessary (sorghum, teff and amaranth). The obtained experimental wort and beer samples were analytically characterised to rationally assess the impact of the addition of the alternative raw materials. After descriptive sensory evaluation of the beers, the preferred ingredients were einkorn, khorasan and teff.
When scaling up to pilot scale, both a conventional lauter tun and a thin bed filter were used. The behaviour of the cereals during the brewing process was monitored in comparison to reference brews. After several trials, with einkorn, khorasan and teff, good beers were obtained on each installation with good efficiency. Excessive amounts of husk (einkorn) resulted in lower yields with the lauter tun. Teff was very difficult to grind due to its small grain size, both via dry grinding (lauter tun) and wet grinding (thin bed filter). All fresh beers were characterised analytically and sensorially. Insight was also gained on beer preservation, which is especially important for export.
Based on the obtained knowledge and experience on pilot scale, the alternative cereals could be implemented on an industrial scale with relative ease, resulting in innovative high-quality beers with a lot of commercial potential. Brewing experiences were compiled in the form of information sheets in a detailed manual for brewers to get started.