title: Screening and identification of precursor compounds of dimethyl trisulfide (DMTS) in Japanese sake.
abstract: Dimethyl trisulfide (DMTS) is involved in the unpalatable aroma of stale sake, called "hineka"; however, the mechanism underlying the formation of DMTS during the storage of sake has not been elucidated. This paper investigates the precursors of DMTS in sake. An experiment using [methyl-d(3)]-methionine showed that Strecker degradation of methionine plays a minor role in the formation of DMTS. Separation of components in sake by cation exchange resin revealed that DMTS precursors are present in the acidic/neutral fraction rather than in the basic one. Purification of the DMTS precursor compounds was carried out through several chromatographic steps, measuring DMTS-producing potential as an index. High-resolution ESI-MS and 1D/2D NMR experiments enabled the identification of one of the precursor compounds as 1,2-dihydroxy-5-(methylsulfinyl)pentan-3-one.
authors.affiliation: National Research Institute of Brewing, Higashihiroshima, Japan. isogai@nrib.go.jp
authors.forename: Atsuko
authors.initials: A
authors.lastname: Isogai
authors.forename: Ryoko
authors.initials: R
authors.lastname: Kanda
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Hiraga
authors.forename: Toshihide
authors.initials: T
authors.lastname: Nishimura
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Iwata
authors.forename: Nami
authors.initials: N
authors.lastname: Goto-Yamamoto
mesh_terms: D000434:Alcoholic Beverages / Q000032:analysis*; D007564:Japan; D009682:Magnetic Resonance Spectroscopy; D009812:Odorants / Q000032:analysis*; D010422:Pentanones / Q000032:analysis; D021241:Spectrometry, Mass, Electrospray Ionization; D013440:Sulfides / Q000032:analysis* / Q000737:chemistry*
chemical_list: C534943:1,2-dihydroxy-5-(methylsulfinyl)pentan-3-one; D010422:Pentanones; D013440:Sulfides; C054170:dimethyl trisulfide