Sensory and analytical characterization of nonvolatile taste-active compounds in bottom-fermented beers

A systematic sensory and analvtical screening of nonvolatile substances in beer and the determination of thresholds of those compounds in water and beer, as well as clarification of additive and synergistic effects, were earried out to give a clearer insight into the constitution of beer. While investigating amino acids, organic acids. B-group vitamins, and minerals and anions, it was accrtained that potassium, citric acid, γ-amino-butyrie acid, magnesium, malie acid, pyruvic acid, lactic acid, acetic acid, L-glutamic acid, and L-aspartic acid contribute to beer taste and are used to calculate their taste activity value (TAV). It was also shown that taste threshold values TTV) of the investigated substances vary in regard to the media in which the determination is carried out. However, it could be shown that TTV in beer are not nceessarily higher than those in water. The chemical composition of the beer type or beer brand plays an important role in the TTV and, therefore, also to the TAV. Compounds that contribute through their concentration to the laste of one beer might not contribute to the beer taste in a different beer because of the beer's anique matrix. The compounds that have been found taste active can he associated either with the raw materials or with their genesis in the course of the brewing process. This knowledge provides the possibility to modify technological processes to shift the beer last in a specified direction in a cuntrolled manner.