title: SDE and SPME Analysis of Flavor Compounds in Jin Xuan Oolong Tea.
abstract: Simultaneous distillation-extraction (SDE) and solid phase micro extraction (SPME) are procedures used for the isolation of flavor compounds in foods. The purpose of this study was to optimize SDE conditions (solvent and time) and to compare SDE with SPME for the isolation of flavor compounds in Jin Xuan oolong tea using GC-MS and GC-O. The concentration of volatile compounds isolated with diethyl ether was higher (P < 0.05) than for dichloromethane and concentration was higher at 40 min (P < 0.05) than 20 or 60 min extractions. For SDE, 128 volatiles were identified using GC-MS and 45 aroma active compounds using GC-O. Trans-nerolidol was the most abundant compound in oolong tea. The number of volatiles identified using GC-MS was lower in SPME than SDE. For SPME, 59 volatiles and 41 aroma active compounds were identified. The composition of the volatiles isolated by the 2 methods differed considerably but provided complementary information.
authors.affiliation: Dept. of Food Science and Technology, Virginia Tech, Blacksburg, Va., U.S.A.
authors.forename: Ershad
authors.initials: E
authors.lastname: Sheibani
authors.affiliation: Dept. of Food Science and Technology, Virginia Tech, Blacksburg, Va., U.S.A.
authors.forename: Susan E
authors.initials: SE
authors.lastname: Duncan
authors.affiliation: Dept. of Food Science and Technology, Virginia Tech, Blacksburg, Va., U.S.A.
authors.forename: David D
authors.initials: DD
authors.lastname: Kuhn
authors.affiliation: Dept. of Civil and Environmental Engineering, Virginia Tech, Blacksburg, Va., U.S.A.
authors.forename: Andrea M
authors.initials: AM
authors.lastname: Dietrich
authors.affiliation: Dept. of Food Science and Technology, Virginia Tech, Blacksburg, Va., U.S.A.
authors.forename: Sean F
authors.initials: SF
authors.lastname: O'Keefe
mesh_terms: D028241:Camellia sinensis / Q000737:chemistry*; D057168:Distillation / Q000379:methods*; D005421:Flavoring Agents / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D006801:Humans; D052617:Solid Phase Microextraction / Q000379:methods*; D013649:Taste; D013662:Tea / Q000737:chemistry*; D055549:Volatile Organic Compounds / Q000032:analysis*
chemical_list: D005421:Flavoring Agents; D013662:Tea; D055549:Volatile Organic Compounds
keywords: GC-MS; GC-O; SDE; SPME; oolong tea