Determination of l-cysteine origin on the basis of its δ15N values. (15th September 2018)

• Record Type: Journal Article
• Authors: Bichon, Emmanuelle; Sitthisack, Parina; Sérée-Vattier, Ludivine; Prévost, Stéphanie; Schiphorst, Anne-Marie; Pouponneau, Karinne; Monteau, Fabrice; Le Bizec, Bruno
• Is Part Of: Food chemistry. Volume 260(2018)
• Page Start: 283
• Page End: 288
• Publication Date: 2018-09-15
• Subjects: EA/IRMS -- Cysteine -- Cystine -- Carbocysteine -- Validation -- Origin determination; Cysteine (PubChem CID: 5862) -- Cystine (PubChem CID: 67678) -- Carbocysteine (PubChem CID: 1080); Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2018.03.139
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: δ 15 N-EA/IRMS analysis of cysteine. Δδ 15 N of 2‰ between cystine extracted from feathers and from hair. Validation of the methodology based on a LAB GTA 25 requirements. Correlation between cystine origin and δ 15 N/δ 13 C values. Abstract: The majority ofl -cysteine is obtained industrially by hydrolysis of animal materials, such as poultry feathers. Despite widespread belief, there is little evidence that human hair is used as a source material and its use is explicitly banned in the European Union (2000/63/EC decision). We developed an isotope ratio mass spectrometric (EA-IRMS) method to determine carbon and nitrogen isotopic ratio in cysteine preparations and related compounds, e.g. cystine and carbocysteine. A threshold relying on the 15 N/ 14 N was established to differentiate between hair and feathers; a value below 6.6‰ indicates a poultry feathers origin. Global uncertainty of measurement was found to be 0.1‰ for δ 15 N (sample size of 0.5–1.8 mg).