Authentication of beef versus horse meat using 60MHz 1H NMR spectroscopy

TLDR

The study proposes a screening protocol that distinguishes beef from horse meat by comparing triglyceride signatures obtained with 60 MHz ¹H NMR spectroscopy. Using a chloroform extraction, the authors acquire low‑field triglyceride spectra in about 10 min and apply Naïve Bayes classification and PCA to separate the two meats, testing the method on freeze‑thawed and unseen samples. The approach correctly classifies 90 of 91 beef and all 16 horse samples, with freezing having no adverse effect, demonstrating that 60 MHz ¹H NMR is a feasible high‑throughput screening method.

Abstract

This work reports a candidate screening protocol to distinguish beef from horse meat based upon comparison of triglyceride signatures obtained by 60 MHz 1H NMR spectroscopy. Using a simple chloroform-based extraction, we obtained classic low-field triglyceride spectra from typically a 10 min acquisition time. Peak integration was sufficient to differentiate samples of fresh beef (76 extractions) and horse (62 extractions) using Naïve Bayes classification. Principal component analysis gave a two-dimensional "authentic" beef region (p = 0.001) against which further spectra could be compared. This model was challenged using a subset of 23 freeze–thawed training samples. The outcomes indicated that storing samples by freezing does not adversely affect the analysis. Of a further collection of extractions from previously unseen samples, 90/91 beef spectra were classified as authentic, and 16/16 horse spectra as non-authentic. We conclude that 60 MHz 1H NMR represents a feasible high-throughput approach for screening raw meat.