Rapid identification and quantitation of pork and duck meat of binary and ternary adulteration in minced beef by 1H NMR combined with multivariate data fusion

Rapid identification and quantification of pork and duck meat adulterated in ground beef were successfully performed by 1H NMR spectra combined with chemometrics. In principal component analysis (PCA), beef had a higher content of methionine and glutamine, which may be the key to distinguishing beef from pork and duck. Both of the binary and ternary adulterated beef could be successfully discriminated by orthogonal partial least squares discriminant analysis (OPLS-DA), with a discrimination accuracy of 100%. Leucine, isoleucine, methionine and glutamine were screened out as the potential markers for beef adulteration. After verification by external samples, the partial least squares (PLS) model was proved to be accurate in predicting binary and ternary adulteration levels in beef, with the determination coefficients R2p of 0.9153 and 0.9348, respectively, and the root mean square error (RMSEP) of 0.1112 and 0.0821, respectively. These results provide a comprehensive perspective on beef adulteration and improve understanding of the relationship between metabolites and meat.