Analytical and sensory profiles of Slovenian and Czech hop genotypes in single hopped beers

Abstract

The sensory profile of beer is influenced by the hop variety and hopping technology. This study examined pilot (50 L) pale lager beers, hopped in the kettle with (or without) single dry hopping. Seven Slovenian, four Czech and one American genotypes were used to determine the impact of dry hopping on the sensory and volatile profiles of beer. Descriptive and bitterness lingering assessment sensory methods were used. The essential oil composition of the hops and beers was accessed using GC/MS so as to clarify their correlation to sensory profiles of both brewing processes. Changes in essential oils and aroma profiles of beer related to storage were evaluated. Results showed differences among the genotypes in the hop oil profiles in the kettle-hopped beers. Based on the hop dose, dry hopping increased the monoterpene alcohol (r = 0.60) and monoterpene hydrocarbon (r = 0.74) content. Hoppy flavour correlated to the monoterpene alcohols and hydrocarbons. Hop-derived aroma profiles of the genotypes differed. Dry-hopped beers tended to have a more bitter aftertaste than solely kettle-hopped beers. Both kettle and dry hopped beers of all genotypes showed good sensory acceptance (3-4.5; nine-point scale). After storage of beer, the content of most essential oils and hoppy flavour significantly decreased. The sensory aging of the kettle and dry-hopped beers was comparable.