| Title: | Dry-Hopping to Modify the Aroma of Alcohol-Free Beer on a Molecular Level-Loss and Transfer of Odor-Active Compounds |
| Author(s): | Brendel S; Hofmann T; Granvogl M; |
| Address: | "Lehrstuhl fur Lebensmittelchemie und Molekulare Sensorik, Technische Universitat Munchen, Wissenschaftszentrum Weihenstephan fur Ernahrung, Landnutzung und Umwelt, Lise-Meitner-Strasse 34, D-85354 Freising, Germany. Leibniz-Institut fur Lebensmittel-Systembiologie an der Technischen Universitat Munchen, Lise-Meitner-Strasse 34, D-85354 Freising, Germany. Institut fur Lebensmittelchemie, Fachgebiet Lebensmittelchemie und Analytische Chemie (170a), Fakultat Naturwissenschaften, Universitat Hohenheim, Garbenstrasse 28, D-70599 Stuttgart, Germany" |
| ISSN/ISBN: | 1520-5118 (Electronic) 0021-8561 (Linking) |
| Abstract: | "There are mainly two options for the dealcoholization of beer: evaporation of ethanol by heat treatment, whereby desired aroma-active compounds are also removed, and stopped fermentation that leads to beers still containing high amounts of unfermented sugar in parallel with lower amounts of aroma-active fermentation products. Thus, dry-hopping could be an opportunity to compensate for these aroma deficiencies. Therefore, following the sensomics approach, odorants were characterized in dry-hopped (Hallertauer Mandarina Bavaria, Hallertauer Cascade, or Hallertauer Mittelfruh) top- and bottom-fermented alcohol-free beers either after thermal dealcoholization or stopped fermentation. Twenty-three odorants were quantitated via stable isotope dilution analysis, and odor activity values (OAVs; ratio of concentration to odor threshold) were calculated. Thermally dealcoholized samples showed high losses (up to 100%) of key odorants like 3-methyl-1-butanol or 3-methylbutyl acetate. During stopped fermentation, aroma compounds like ethyl butanoate or 2-phenylethanol were formed in relevant concentrations, leading to OAVs >/= 1, but the amounts were significantly lower compared to beers with normal alcohol contents. For hop-derived odorants (linalool, geraniol, myrcene, and esters), transfer rates between 20 and 90% were found, leading to OAVs >/= 1 in beer. Furthermore, hop addition apparently induced the formation of ethyl esters of hop-derived monocarboxylic acids" |
| Keywords: | Beer/*analysis Ethanol/analysis Fermentation Flavoring Agents/*chemistry Gas Chromatography-Mass Spectrometry Humulus/chemistry Odorants/analysis Volatile Organic Compounds/chemistry Humulus lupulus L.alcohol-free beer aroma extract dilution analysis dry; |
| Notes: | "MedlineBrendel, Sabrina Hofmann, Thomas Granvogl, Michael eng 2020/07/14 J Agric Food Chem. 2020 Aug 12; 68(32):8602-8612. doi: 10.1021/acs.jafc.0c01907. Epub 2020 Jul 28" |
