title: Assessment of the aroma impact of major odor-active thiols in pan-roasted white sesame seeds by calculation of odor activity values.
abstract: Eleven odor-active thiols, namely, 2-methyl-1-propene-1-thiol, (Z)-3-methyl-1-butene-1-thiol, (E)-3-methyl-1-butene-1-thiol, (Z)-2-methyl-1-butene-1-thiol, (E)-2-methyl-1-butene-1-thiol, 2-methyl-3-furanthiol, 3-mercapto-2-pentanone, 2-mercapto-3-pentanone, 4-mercapto-3-hexanone, 3-mercapto-3-methylbutyl formate, and 2-methyl-3-thiophenethiol, recently identified in an extract prepared from white sesame seeds, were quantitated in sesame using stable isotope dilution analyses. For that purpose, the following deuterium-labeled compounds were synthesized and used as internal standards in the quantitation assays: [2H6]-2-methyl-1-propene-1-thiol, [2H3]-(E)- and [2H3]-(Z)-2-methyl-1-butene-1-thiol, [2H3]-2-methyl-3-furanthiol, [2H2]-3-mercapto-2-pentanone, [2H3]-4-mercapto-3-hexanone, [2H6]-3-mercapto-3-methylbutyl formate, and [2H3]-2-methyl-3-thiophenethiol. On the basis of the results obtained, odor activity values (OAVs) were calculated as ratio of the concentration and odor threshold of the individual compounds in cooking oil. According to their high OAVs, particularly the 3-methyl-1-butene-1-thiols (OAV: 2400) and the 2-methyl-1-butene-1-thiols (OAV: 960) were identified as the most odor-active compounds in pan-roasted white sesame seeds. These compounds were therefore suggested to be mainly responsible for the characteristic but rather unstable sulfury aroma of freshly pan-roasted white sesame seeds.
authors.affiliation: Technical Research Institute, R&D Center, T. Hasegawa Company, Ltd., 29-7, Kariyado, Nakahara-ku, Kawasaki-shi 211-0022, Japan. hitoshi_tamura@t-hasegawa.co.jp
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Tamura
authors.forename: Akira
authors.initials: A
authors.lastname: Fujita
authors.forename: Martin
authors.initials: M
authors.lastname: Steinhaus
authors.forename: Eisuke
authors.initials: E
authors.lastname: Takahisa
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Watanabe
authors.forename: Peter
authors.initials: P
authors.lastname: Schieberle
mesh_terms: D003903:Deuterium; D006358:Hot Temperature; D007201:Indicator Dilution Techniques; D009812:Odorants / Q000032:analysis*; D012639:Seeds / Q000737:chemistry*; D031685:Sesamum / Q000737:chemistry*; D013438:Sulfhydryl Compounds / Q000032:analysis*
chemical_list: D013438:Sulfhydryl Compounds; D003903:Deuterium