Flavor Characteristics of cis-3-Nonenal in Beer. Shuso Sakuma and Masahiro Kowaka, Technology Development Department, Beer Division, Kirin Brewery Co. Ltd., 17-1 Namamugi 1-chome, Tsurumi-ku, Yokohama, 230 Japan. J. Am. Soc. Brew. Chem. 52:0037, 1994.

The flavor threshold of cis-3-nonenal in beer was determined to be 0.5 µg/L by the ascending method of limits test. The flavor imparted by cis-3-nonenal was not a cardboard flavor but a soybean-oil-like flavor. Various concentrations of cis-3-nonenal were added to fresh beer, which was then stored at 5° C. After one day of storage, the flavor intensity of the sample containing the added substance had increased and the beer was considered to have a cardboard flavor. An analytical method was developed to determine the independent concentrations of cis-3-nonenal and trans-2-nonenal in beer. Fresh bottled beer was aged at 38° C for eight days, and the concentrations of cis-3-nonenal and trans-2-nonenal were determined during the storage period. In fresh beer, a concentration of 0.05 µg/L of trans-2-nonenal was detected, but cis-3-nonenal could not be detected. During storage, the concentration of trans-2-nonenal continued to increase; however, cis-3-nonenal was not detected.

Keywords: Beer, cis-3-Nonenal, Determination, Flavor threshold, trans-2-Nonenal