title: Occurrence of odorant polyfunctional thiols in beers hopped with different cultivars. First evidence of an S-cysteine conjugate in hop (Humulus lupulus L.).
abstract: Forty-one thiols, mainly β-sulfanylalkyl acetates, β-sulfanylalkyl alcohols, and β-sulfanylalkyl carbonyls, were recently evidenced in hop. In a beer hopped with the Tomahawk cultivar, most of them were found at higher levels than expected. The aim of the present work was to investigate the polyfunctional thiols in beers hopped with different varieties. A few thiols proved not to come only from hop (mainly 2-sulfanylethyl acetate, μg/L levels, and 1-sulfanylpentan-3-one and 1-sulfanylpentan-3-ol, ng/L levels, internal standard (IST) equivalents). The thiol profile of Saaz-hopped beer proved similar to that of the reference beer produced without hop. A high level of 3-sulfanyloctan-1-ol emerged as an indicator of the use of Tomahawk hop (140 ng/L, IST equivalents; FD (flavor dilution) = 65536). In both Cascade- and Tomahawk-hopped beers, 3-sulfanylhexan-1-ol and 3-sulfanylheptan-1-ol were smelled at high flavor dilutions, although only for the latter, significant amounts of the unreduced 3-sulfanylheptanal were found in hop. As already claimed for hop authentication, 3-sulfanyl-4-methylpentan-1-ol remains a good marker of Nelson Sauvin-hopped beers (548 ng/L, IST equivalents; FD = 65536), together with 4-sulfanyl-4-methylpentan-2-one (128 ng/L, FD = 4096). As illustrated by the huge production occurring during fermentation, accurate prediction of hop varietal impact requires quantitating thiol adducts in hop. S-3-(1-Hydroxyhexyl)cysteine was evidenced here for the first time in Cascade hop.
authors: Unité de brasserie et des industries alimentaires, Earth and Life Institute ELIM, Faculté d'Ingénierie biologique, agronomique et environnementale, Université catholique de Louvain, Louvain-la-Neuve, Belgium.
authors: Jacques
authors: J
authors: Gros
authors: Florence
authors: F
authors: Peeters
authors: Sonia
authors: S
authors: Collin
mesh_terms: D001515:Beer / Q000032:analysis*; D002849:Chromatography, Gas; D003545:Cysteine / Q000031:analogs & derivatives* / Q000032:analysis; D006801:Humans; D027582:Humulus / Q000737:chemistry*; D009812:Odorants / Q000032:analysis*; D010936:Plant Extracts / Q000737:chemistry; D012903:Smell; D013438:Sulfhydryl Compounds / Q000032:analysis*
chemical_list: D010936:Plant Extracts; D013438:Sulfhydryl Compounds; D003545:Cysteine