title: Determination of Nepsilon-(carboxymethyl)lysine in food systems by ultra performance liquid chromatography-mass spectrometry.
abstract: We report the use of ultra pressure liquid chromatography (UPLC), coupled to a tandem mass spectrometer operated in multiple reaction monitoring mode to determine the advanced glycation endproduct, Nepsilon-(carboxymethyl)lysine (CML). The procedure was applied to acid hydrolyzates of protein isolated from a range of foods (milks processed at different temperatures, butter, cheese, infant formulae, bread, raw and cooked minced beef and olive oil). Highest levels of CML were determined in white bread crust (15.2 +/- 0.63 mmol/mol Lys), wholemeal bread crust (13.1 +/- 0.61 mmol/mol Lys) and evaporated full-fat milk (4.86 +/- 0.77 mmol/mol Lys). Lowest levels of CML were measured in raw minced beef beef (0.03 +/- 002 mmol/mol Lys), raw full-fat cow's milk (0.08 +/- 0.03 mmol/mol Lys) and pasteurized skimmed cow's milk (0.09 +/- 0.002 mmol/mol Lys). CML could not be detected in olive oil.
authors.affiliation: Human Nutrition and Health Group, School of Biological Sciences, Queen's University Belfast, David Keir Building, Stranmillis Road, Belfast BT9 5AG, UK.
authors.forename: Shima H
authors.initials: SH
authors.lastname: Assar
authors.forename: Catherine
authors.initials: C
authors.lastname: Moloney
authors.forename: Maria
authors.initials: M
authors.lastname: Lima
authors.forename: Ronald
authors.initials: R
authors.lastname: Magee
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Ames
mesh_terms: D000818:Animals; D001939:Bread / Q000032:analysis; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005504:Food Analysis / Q000379:methods*; D008239:Lysine / Q000031:analogs & derivatives* / Q000032:analysis; D008460:Meat / Q000032:analysis; D008892:Milk / Q000737:chemistry; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: C048496:N(6)-carboxymethyllysine; D008239:Lysine