title: A novel method for the quantification of quinic acid in food using stable isotope dilution analysis.
abstract: Organic acids play an important role in the flavor and taste of plant-derived foods. Quinic acid (QA) is one of the major acids. In the past, several methods like HPLC/UV, GC, and capillary electrophoresis were used for identification and quantification of QA. For the first time, a novel, sensitive, and selective method for the quantification of QA in food using stable isotope dilution analysis with HPLC/MS/MS has been established. Uniformly labeled 13C-QA was used as a standard to reduce sample preparations and to overcome matrix and ionization effects. The method was used to determine the QA content of red wines, instant coffees, and cloudy apple juices. QA contents of instant coffees were 64.4 and 63.6 g/kg powder. The concentrations in red wines were 24.0 and 25.1 mg/L, and 1493.3 and 1705.2 mg/L in cloudy apple juices.
authors.affiliation: University of Kaiserslautern, Department of Chemistry, Division of Food Chemistry and Toxicology, Erwin-Schroedinger-Str. 52, 67663 Kaiserslautern, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Erk
authors.forename: Hannah
authors.initials: H
authors.lastname: Bergmann
authors.forename: Elke
authors.initials: E
authors.lastname: Richling
mesh_terms: D002138:Calibration; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005504:Food Analysis / Q000379:methods*; D007201:Indicator Dilution Techniques; D011801:Quinic Acid / Q000032:analysis*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D014920:Wine / Q000032:analysis
chemical_list: D011801:Quinic Acid