Some Changes in Beer Flavour During Ageing

Bottled beers were stored for 5–6 months at 0° C., 25° C. and 40° C. At the highest temperature, decreases in the concentrations of ethyl acetate and isoamyl acetate were found. Ethyl formate showed an increase in concentration, and the concentration of acetaldehyde increased at the beginning of storage, and decreased thereafter. At the lower temperatures the changes in concentrations of these compounds were considerably smaller; at 0° C. they were hardly detectable in most cases. Different beer types, fermented with the same yeast strain, behaved differently on ageing.