Use of GC-olfactometry to identify the hop aromatic compounds in beer

This paper describes a sensorial aroma extract dilution analysis (AEDA) app roach to the analysis of beer aromas derived from hops. To obtain an extrac t with an odor representative of the original product, the XAD extraction p rocedure was applied and the experimental conditions were optimized. The ar omagrams of three beers were compared: one brewed without hops, one brewed with Saaz hop pellets, and one brewed with Challenger hop pellets. One spic y/hoppy compound, unmodified from hop to beer, proved responsible for the m ost intense odor in both hopped beer extracts. Another flavoring compound i n hops, linalool, also survives through the process to the final beer. Othe r compounds such as gamma -nonalactone and humuladienone, although not foun d in our extracts of hop, significantly modify beer aromagrams after hoppin g. Sulfur compounds characteristic of Challenger hops proved to be at least partially responsible for the unpleasant flavor found in the corresponding beer.