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Simultaneous quantification of the boar-taint compounds skatole and androstenone by surface-enhanced Raman scattering (SERS) and multivariate data analysis


This study investigates the feasibility of using surface-enhanced Raman scattering (SERS) for the quantification of absolute levels of the boar-taint compounds skatole and androstenone in porcine fat. By investigation of different types of nanoparticles, pH and aggregating agents, an optimized environment that promotes SERS of the analytes was developed and tested with different multivariate spectral pre-processing techniques, and this was combined with variable selection on a series of analytical standards. The resulting method exhibited prediction errors (root mean square error of cross validation, RMSECV) of 2.4 × 10−6 M skatole and 1.2 × 10−7 M androstenone, with a limit of detection corresponding to approximately 2.1 × 10−11 M for skatole and approximately 1.8 × 10−10 for androstenone. The method was subsequently tested on porcine fat extract, leading to prediction errors (RMSECV) of 0.17 μg/g for skatole and 1.5 μg/g for androstenone. It is clear that this optimized SERS method, when combined with multivariate analysis, shows great potential for optimization into an on-line application, which will be the first of its kind, and opens up possibilities for simultaneous detection of other meat-quality metabolites or pathogen markers.

Artistic rendering of a laser-illuminated gold colloid sphere with skatole and androstenone adsorbed on the surface

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The authors would like to thank Chief Research Scientist Hanne Maribo (Danish Centre for Pig Research, Axelborg, Axeltorv 3, DK-1609 Copenhagen V, Denmark, for providing the biological sample material. The work was supported by the Danish National Advanced Foundation (Holbergsgade 14 3, DK-1057 Copenhagen, Denmark) in a project in cooperation with Carometec A/S, Transformervej 9, DK-2730 Herlev, Denmark. C.W. and R.G. thank UK BBSRC for the support of C.W. PhD studentship.

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Correspondence to Klavs M. Sørensen.

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Klavs M. Sørensen and Chloe Westley contributed equally to this work. All authors contributed to the experimental design and to the manuscript.

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Sørensen, K.M., Westley, C., Goodacre, R. et al. Simultaneous quantification of the boar-taint compounds skatole and androstenone by surface-enhanced Raman scattering (SERS) and multivariate data analysis. Anal Bioanal Chem 407, 7787–7795 (2015).

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  • Boar taint
  • Porcine fat
  • Androstenone
  • Skatole
  • Surface-enhanced Raman scattering (SERS)
  • Multivariate calibration