Assessment of milk fat content in fat blends by 13C NMR spectroscopy analysis of butyrate. (September 2018)

• Record Type: Journal Article
• Authors: Sacchi, Raffaele; Paduano, Antonello; Caporaso, Nicola; Picariello, Gianluca; Romano, Raffaele; Addeo, Francesco
• Is Part Of: Food control. Volume 91(2018)
• Page Start: 231
• Page End: 236
• Publication Date: 2018-09
• Subjects: 13C NMR -- Milk fat -- Butyric acid -- Authenticity -- Fat blends; IDF International Dairy Federation -- GC High Resolution Gas-liquid Chromatography -- TAGs Triacylglycerols -- EI Electron Ionization -- MS Mass Spectrometry -- LC-APCI-MS/MS Liquid Chromatography-Atmospheric Pressure Chemical Ionization-Mass Spectrometry -- BA Butyric Acid -- NMR Nuclear Magnetic Resonance -- FAMEs Fatty Acid Methyl Esters -- NOEs Nuclear Overhauser Effects -- BB Broad Band -- TMS tetramethylsilane; Food -- Quality -- Periodicals; Food -- Analysis -- Periodicals; Food handling -- Periodicals; Food industry and trade -- Quality control -- Periodicals; Aliments -- Industrie et commerce -- Qualité -- Contrôle -- Périodiques; Aliments -- Qualité -- Périodiques; Aliments -- Analyse -- Périodiques; Hygiène alimentaire -- Périodiques; Food -- Analysis; Food handling; Food -- Quality; Periodicals; Electronic journals; 664.07
• DOI: 10.1016/j.foodcont.2018.04.011
• Languages: English
• ISSNs: 0956-7135

Abstract

Abstract: Butyric acid (butyrate) is a candidate marker of milk fat in complex fat blends, since it is exclusive of milk triacylglycerols (TAGs) from different ruminant species. In this work, we determined the amount of milk fat used for the preparation of fat blends by 13 C Nuclear Magnetic Resonance ( 13 C NMR) spectroscopy-based quantification of butyrate. When tested on fat samples spiked with known amounts of reference bovine milk fat (BCR-519 certified material), the relative composition of the mixtures was reliably assessed through the integration of the diagnostic 13 C NMR carbonyl (C1) or α-carbonyl methylene (C2) resonances of butyrate. NMR data exhibited strict correlation with high resolution-gas chromatography (GC) of fatty acid methyl esters (R 2 = 0.99), which was used as an independent and well-established method for the determination of butyrate. Thus, 13 C NMR can be used for the direct assessment of milk fat content in fat mixtures, at a limit of detection lower than 5%, with clear advantages over the traditional GC methods in terms of speed, robustness and minimal sample handling. The natural variability of butyrate in milk has been taken into account to estimate the uncertainty associated with the milk fat content in unknown fat blends. Highlights: Triacylglycerol-esterified butyrate is a valuable marker of milk fat in fat blends. Butyrate can be determined by 13 C NMR through diagnostic C1 or C2 resonances. 13 C NMR enables the direct assessment of milk fat content in fat mixtures. 13 C-NMR-based determination exhibited strict correlation with GC analysis of fatty acids. Natural butyrate fluctuation affects the accurate determination of milk fat in fat blends.