AROMA COMPONENTS ANALYSIS BY HS-SPME/GC-MS TO CHARACTERIZE LAGER, ALE, AND SOUR BEER STYLES

The world of beer is a rich tapestry woven with diverse styles, each with its unique character. Lager, known for its crispness, ferments at lower temperatures, while ale, at warmer ones, boasts a wide spectrum of aromas. Belgian beers dazzle with their complexity, from fruity Trappist ales to sour lambics. German wheat beers, like hefeweizens, charm with their effervescence and fruity undertones. India Pale Ales (IPAs) showcase a hoppy burst, while sour ales tantalize with their tanginess. Craftsmanship, history, and regional ingredients intertwine in this world of brewing, offering aficionados an array of delightful experiences. To date, studies of craft beers aroma are still limited, and the identification of molecular fingerprint indicators could offer a key strategy to protect beer from food frauds. To the purpose, the present study aims to characterize the aroma profile of a wide range of beers by using HS-SPME/GC–MS (Head Space-Solid Phase Micro Extraction/Gas Chromatography-Mass Spectrometry) technique combined with multivariate data processing to identify specific product markers able to distinguish categories of beers styles. A total of 121 beer samples were collected and divided into five categories: Pilsen (n=28); Lager (n=24); Ale (n=31); Sour (n=25); and Belgian Ales (n=13). Among the Pilsen beers, 18 unique compounds were found for beers with hop extract and hops, and 2 for beers with hop extract (Octyl acetate; and alpha-Terpineol). When comparing the remaining groups to each other, Belgian beers exhibited 6 unique compounds, and Lagers had 2 (Isobutyl acetate; and Hexyl acetate). Sours and Ales did not have unique compounds but shared 2 distinct compounds with the Belgian group each. We concluded that Belgian beers are the most complex in terms of various aroma-related compounds, and that it is possible to distinguish beers that use pure hops from hop extract.