title: Stable isotope ratio measurements of royal jelly samples for controlling production procedures: impact of sugar feeding.
abstract: The carbon and nitrogen stable ratios of royal jelly (RJ) samples from various origins are determined using an elemental analyser linked online to an isotope ratio mass spectrometer to evaluate authenticity and adulteration. The (13)C/(12)C and (15)N/(14)N stable isotope ratios are measured in more than 500 RJs (domestic, imported and derived from feeding experiments) in order to obtain isotopic measurements that take into account seasonal, botanical and geographical effects. Authenticity intervals are established for traditional beekeeping practices, without feeding, in the range -22.48 to -27.90‰ for δ(13)C. For these samples, the δ(15)N values range from -1.58 to 7.98‰, depending on the plant sources of pollen and nectar. The δ(13)C values of the commercial samples vary from -18.54 to -26.58‰. High δ(13)C values are typical of sugar cane or corn syrups which have distinctive isotopic (13)C signatures because both plants use the C4 photosynthetic cycle, in contrast to most RJs which are derived from C3 plants. These differences in the (13)C-isotopic composition allow the detection of the addition of such sugars. RJs from traditional sources and from industrial production by sugar feeding are thus successfully distinguished.
authors.affiliation: UMR5280, CNRS-Service Central d'Analyse, Echangeur de Solaize, Chemin du Canal, 69360 Solaize, France. g.daniele@sca.cnrs.fr
authors.forename: Gaëlle
authors.initials: G
authors.lastname: Daniele
authors.forename: Marine
authors.initials: M
authors.lastname: Wytrychowski
authors.forename: Magali
authors.initials: M
authors.lastname: Batteau
authors.forename: Sylvie
authors.initials: S
authors.lastname: Guibert
authors.forename: Hervé
authors.initials: H
authors.lastname: Casabianca
mesh_terms: D000818:Animals; D001516:Bees; D002241:Carbohydrates / Q000737:chemistry / Q000145:classification; D002247:Carbon Isotopes / Q000032:analysis*; D005227:Fatty Acids / Q000032:analysis / Q000737:chemistry* / Q000592:standards; D013058:Mass Spectrometry; D009587:Nitrogen Isotopes / Q000032:analysis*; D013549:Sweetening Agents; D000099219:Royal Jelly
chemical_list: D002241:Carbohydrates; D002247:Carbon Isotopes; D005227:Fatty Acids; D009587:Nitrogen Isotopes; D013549:Sweetening Agents; D000099219:Royal Jelly