Influence of kilned specialty malt odorant markers on the aroma composition and sensory profile of beer

Specialty malt beers are brewed with the intention of providing distinct flavour and colour. To this end, special malts have different chemical compositions. More specifically, the availability of enzymes, small peptides, organic acids, Maillard products, low-molecular weight sugars and amino acids depend on the malting procedure applied and thus vary between the malt styles. To investigate the influence of kilned specialty malts (KSM) on the properties of wort and beer, brewing trials were carried out adding 10 and 20% of pale ale, Vienna, Munich or melanoidin malt. Alongside sensory analysis, the aroma composition of each beer was investigated throughout their brewing processes, revealing significant losses of the KSM odorant markers after the boiling process. Statistical analysis indicated a major influence of KSM-derived Maillard aldehydes on the sensory profile of the beers. Finally, the transfer rates of the odorants were calculated from the malt to the beer, suggesting a high influence of the brewing process on the formation of KSM odorants and thus on the aroma composition of the final beer.