Meat Authentication Using HPLC–MS–MS

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Researchers from the Institute of Food Chemistry at Westfälische Wilhelms‑Universität Münster in Germany have developed an optimized high performance liquid chromatography coupled with mass spectrometry (HPLC–MS–MS) method using multiple reaction mode (MRM) and MRM³ for detecting horse and pork in highly processed food. The paper published in the Journal of Agricultural and Food Chemistry outlines the detection of horse or pork meat in different sample matrices. ¹

The issue of food fraud came to the forefront of European news in 2013 when there were widespread reports product mislabelling. In the UK alone there were several cases where products labelled as beef were actually 100% horsemeat. Although eating horsemeat is not necessarily a danger to health, it does cause concern over food supply chain security.

The principle methods used by analysts are enzyme-linked immune sorbent assays (ELISA) and polymerase chain reaction (PCR) methods, but these techniques can lack sensitivity and specificity when applied to processed food samples. Mass spectrometry-based methods have been reported in the field for authentication of meat; the authors of the study report that they have previously published the first MRM-based method for the detection of raw horse and pork in raw beef and chicken by detecting species-specific marker peptides.¹

Samples of beef, pork, and horsemeat were bought in Germany and The Netherlands and were processed in‑house to form meat loafs and frikadeller (very similar to a fried hamburger patty). Commercial samples of salamis, sausages, and canned meat were used for comparison. Around 1 g of each sample was extracted using extraction buffer composed of 6 M urea, 1 M thiourea, and 50 mM Tris–HCL and were subsequently analyzed using HPLC–MS–MS in MRM.

The authors were able to detect trace levels of horse and pork meat at levels of 0.24% in beef meat matrix, and established that the marker peptides used were stable enough to resist thermal processing. The paper also states that the method does not require 2D-PAGE or off-gel fractionation and so the method could be applied in routine analysis. — B.D.

Reference
1. C.V. Bargen et al., Journal of Agricultural and Food Chemistry DOI:10.1021/jf503468t (2014).

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