Skip to main content

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

Abstract

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

This is a preview of subscription content, access via your institution.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5

References

  1. 1.

    INRA (2009) Report on the practice of castration. PIGCAS: Attitudes, practices and state of the art regarding piglet castration in Europe, Deliverable D2.4. French National Institute for Agricultural Research, http://w3.rennes.inra.fr/pigcas/Publicreports/D2:Reportpractice.pdf. Accessed May 2014

  2. 2.

    European Commission (Accessed May 2014) Commission implementing decision of 27 April 2011 amending Decision 89/471/EEC authorising methods for grading pig carcasses in Germany. Accessed L 110/29 89/471/EEC

  3. 3.

    von Borell E, Baumgartner J, Giersing M, Jaeggin N, Prunier A, Tuyttens FAM, Edwards SA (2009) Animal welfare implications of surgical castration and its alternatives in pigs. Animal 3(11):1488–1496. doi:10.1017/s1751731109004728

    Article  Google Scholar 

  4. 4.

    Leidig MS, Hertrampf B, Failing K, Schumann A, Reiner G (2009) Pain and discomfort in male piglets during surgical castration with and without local anaesthesia as determined by vocalisation and defence behaviour. Appl Anim Behav Sci 116(2–4):174–178. doi:10.1016/j.applanim.2008.10.004

    Article  Google Scholar 

  5. 5.

    Maribo H (2012) Screening of organic boars. http://eng.vsp.lf.dk/Research%20results/Finishers/955.aspx. Accessed May 2014. Publication No. 955

  6. 6.

    Prunier A, Brillouet A, Merlot E, Meunier-Salaun MC, Tallet C (2013) Influence of housing and season on pubertal development, boar taint compounds and skin lesions of male pigs. Anim Int J Anim Biosci 7(12):2035–2043. doi:10.1017/s1751731113001596

    CAS  Article  Google Scholar 

  7. 7.

    van Wagenberg CPA, Snoek HM, van der Fels JB, van der Peet-Schwering CMC, Vermeer HM, Heres L (2013) Farm and management characteristics associated with boar taint. Animal 7(11):1841–1848. doi:10.1017/s1751731113001328

    Article  Google Scholar 

  8. 8.

    Colin F, Martin S (2011) Alternative to surgical piglet castration, overview and opportunities to reduce animal pain. Bulletin De L'Académie Veterinaire De France 164(2):155–159

    Article  Google Scholar 

  9. 9.

    Turkstra JA, van der Staay FJ, Stockhofe-Zurwieden N, Woelders H, Meloen RH, Schuurman T (2011) Pharmacological and toxicological assessment of a potential GnRH vaccine in young-adult male pigs. Vaccine 29(21):3791–3801. doi:10.1016/j.vaccine.2011.03.023

    CAS  Article  Google Scholar 

  10. 10.

    Vold E (1970) Fleishproduktionseigenschaften bei Ebern und Kastraten. IV. Organoleptische und gaschromatografische Untersuchungen Wassedampfflüchtiger Stooffe des Rückenspeckes von Ebern. Meldinger Nordandbruckhoegskole 49:1–25

    Google Scholar 

  11. 11.

    Walstra PM, H (1970) Onderzoek geslachtgeur van mannelijke mestvarkens. Researchgroep Vlees en Vleesvare TNO, Zeist, The Netherlands (Rap. C-147):1–30

  12. 12.

    Patterson R (1968) 5alpha-androst-16-ene-3-1 - compound responsible for taint in boar fat. J Sci Food Agric 19(1):31–38. doi:10.1002/jsfa.2740190107

    CAS  Article  Google Scholar 

  13. 13.

    Wilkins CK (1990) Analysis of indole and skatole in porcine gut contents. Int J Food Sci Technol 25(3):313–317

    CAS  Article  Google Scholar 

  14. 14.

    Claus R, Weiler U, Herzog A (1994) Physiological aspects of androstenone and skatole formation in the boar—a review with experimental data. Meat Sci 38(2):289–305. doi:10.1016/0309-1740(94)90118-x

    CAS  Article  Google Scholar 

  15. 15.

    Bonneau M (1998) Use of entire males for pig meat in the European Union. Meat Sci 49:S257–S272

    Article  Google Scholar 

  16. 16.

    Font-i-Furnols M (2012) Consumer studies on sensory acceptability of boar taint: A review. Meat Sci 92(4):319–329. doi:10.1016/j.meatsci.2012.05.009

    Article  Google Scholar 

  17. 17.

    Wysocki CJ, Dorries KM, Beauchamp GK (1989) Ability to perceive androstenone can be acquired by ostensibly anosmic people. Proc Natl Acad Sci U S A 86(20):7976–7978. doi:10.1073/pnas.86.20.7976

    CAS  Article  Google Scholar 

  18. 18.

    Mörlein D (2012) Boar taint: the sensory perspective—olfactory perception, consumer acceptance and trained sensory panel evaluation of boar taint. Zuchtungskunde 84(5):427–438

    Google Scholar 

  19. 19.

    Aluwe M, Tuyttens FAM, Bekaert KM, De Smet S, De Brabander DL, Millet S (2012) Evaluation of various boar taint detection methods. Animal 6(11):1868–1877. doi:10.1017/s1751731112000821

    CAS  Article  Google Scholar 

  20. 20.

    Babol J, Squires EJ (1995) Quality of meat from entire male pigs. Food Res Int 28(3):201–212. doi:10.1016/0963-9969(95)93528-3

    Article  Google Scholar 

  21. 21.

    Meier-Dinkel L, Sharifi AR, Tholen E, Frieden L, Bücking M, Wicke M, Mörlein D (2013) Sensory evaluation of boar loins: trained assessors' olfactory acuity affects the perception of boar taint compounds. Meat Sci 94(1):19–26. doi:10.1016/j.meatsci.2012.12.009

    Article  Google Scholar 

  22. 22.

    Desmoulin B, Bonneau M, Frouin A, Bidard JP (1982) Consumer testing of pork and processed meat from boars—the influence of fat androstenone level. Livest Prod Sci 9(6):707–715. doi:10.1016/0301-6226(82)90018-5

    CAS  Article  Google Scholar 

  23. 23.

    Bekaert KM, Vanden Bussche J, Francois S, Tuyttens FAM, De Brabander HF, Vandendriessche F, Vanhaecke L (2012) A validated ultra-high performance liquid chromatography coupled to high resolution mass spectrometry analysis for the simultaneous quantification of the three known boar taint compounds. J Chromatogr A 1239:49–55. doi:10.1016/j.chroma.2012.03.060

    CAS  Article  Google Scholar 

  24. 24.

    Dehnhard M, Claus R, Hillenbrand M, Herzog A (1993) High-performance liquid-chromatographic method for the determination of 3-methylindole (skatole) and indole in adipose-tissue of pigs. J Chromatogr Biomed Appl 616(2):205–209. doi:10.1016/0378-4347(93)80387-j

    CAS  Article  Google Scholar 

  25. 25.

    Hansenmoller J (1994) Rapid high-performance liquid-chromatographic method for simultaneous determination of androstenone, skatole and indole in back fat from pigs. J Chromatogr Biomed Appl 661(2):219–230. doi:10.1016/s0378-4347(94)80049-9

    CAS  Article  Google Scholar 

  26. 26.

    Garciaregueiro JA, Diaz I (1989) Evaluation of the contribution of skatole, indole, androstenone and androstenols to boar-taint in back fat of pigs by hplc and capillary gas-chromatography (cgc). Meat Sci 25(4):307–316. doi:10.1016/0309-1740(89)90048-x

    CAS  Article  Google Scholar 

  27. 27.

    Fischer J, Elsinghorst PW, Bucking M, Tholen E, Petersen B, Wust M (2011) Development of a candidate reference method for the simultaneous quantitation of the boar taint compounds androstenone, 3 alpha-androstenol, 3 beta-androstenol, skatole, and indole in pig fat by means of stable isotope dilution analysis-headspace solid-phase microextraction-gas chromatography/mass spectrometry. Anal Chem 83(17):6785–6791. doi:10.1021/ac201465q

    CAS  Article  Google Scholar 

  28. 28.

    Fischer J, Haas T, Leppert J, Schulze Lammers P, Horner G, Wust M, Boeker P (2014) Fast and solvent-free quantitation of boar taint odorants in pig fat by stable isotope dilution analysis-dynamic headspace-thermal desorption-gas chromatography/time-of-flight mass spectrometry. Food Chem 158:345–350. doi:10.1016/j.foodchem.2014.02.113

    CAS  Article  Google Scholar 

  29. 29.

    Buttinger G, Karasek L, Verlinde P, Wentz T (2014) In house validation of a reference method for the determination of boar taint compounds by LC-MSMS. JRC88197. Publications Office of the European Union, Geel, Belgium. doi:10.2787/88600

  30. 30.

    van den Berg F, Lyndgaard CB, Sørensen KM, Engelsen SB (2013) Process analytical technology in the food industry. Trends Food Sci Technol 31(1):27–35. doi:10.1016/j.tifs.2012.04.007

    Article  Google Scholar 

  31. 31.

    Sørensen KM, Petersen H, Engelsen SB (2012) An on-line near-infrared (NIR) transmission method for determining depth profiles of fatty acid composition and iodine value in porcine adipose fat tissue. Appl Spectrosc 66(2):218–226. doi:10.1366/11-06396

    Article  Google Scholar 

  32. 32.

    Mathur PK, ten Napel J, Bloemhof S, Heres L, Knol EF, Mulder HA (2012) A human nose scoring system for boar taint and its relationship with androstenone and skatole. Meat Sci 91(4):414–422. doi:10.1016/j.meatsci.2012.02.025

    CAS  Article  Google Scholar 

  33. 33.

    Mörlein D, Meier-Dinkel L, Moritz J, Sharifi AR, Knorr C (2013) Learning to smell: repeated exposure increases sensitivity to androstenone, a major component of boar taint. Meat Sci 94(4):425–431. doi:10.1016/j.meatsci.2013.03.020

    Article  Google Scholar 

  34. 34.

    Mörlein D, Trautmann J, Meier-Dinkel L (2013) Boar taint in male pigs procedure for the selection of test-persons. Fleischwirtschaft 93(4):105–110

    Google Scholar 

  35. 35.

    Lyndgaard LB, Sørensen KM, van den Berg F, Engelsen SB (2012) Depth profiling of porcine adipose tissue by Raman spectroscopy. J Raman Spectrosc 43(4):482–489. doi:10.1002/jrs.3067

    CAS  Article  Google Scholar 

  36. 36.

    Bak KH, Lindahl G, Karlsson AH, Orlien V (2012) Effect of high pressure, temperature, and storage on the color of porcine longissimus dorsi. Meat Sci 92(4):374–381. doi:10.1016/j.meatsci.2012.02.002

    Article  Google Scholar 

  37. 37.

    Beattie JR, Bell SEJ, Borggaard C, Moss BW (2008) Preliminary investigations on the effects of ageing and cooking on the Raman spectra of porcine longissimus dorsi. Meat Sci 80(4):1205–1211. doi:10.1016/j.meatsci.2008.05.016

    CAS  Article  Google Scholar 

  38. 38.

    Pedersen DK, Morel S, Andersen HJ, Engelsen SB (2003) Early prediction of water-holding capacity in meat by multivariate vibrational spectroscopy. Meat Sci 65(1):581–592. doi:10.1016/s0309-1740(02)00251-6

    Article  Google Scholar 

  39. 39.

    Cowcher DP, Xu Y, Goodacre R (2013) Portable, quantitative detection of bacillus bacterial spores using surface-enhanced Raman scattering. Anal Chem 85(6):3297–3302. doi:10.1021/ac303657k

    CAS  Article  Google Scholar 

  40. 40.

    Nie L, Liu F, Ma P, Xiao X (2014) Applications of Gold Nanoparticles in Optical Biosensors. J Biomed Nanotechnol 10(10):2700–2721. doi:10.1166/jbn.2014.1987

    CAS  Article  Google Scholar 

  41. 41.

    Xie W, Schluecker S (2013) Medical applications of surface-enhanced Raman scattering. Phys Chem Chem Phys 15(15):5329–5344. doi:10.1039/c3cp43858a

    CAS  Article  Google Scholar 

  42. 42.

    McNay G, Eustace D, Smith WE, Faulds K, Graham D (2011) Surface-enhanced Raman scattering (SERS) and surface-enhanced resonance Raman scattering (SERRS): a review of applications. Appl Spectrosc 65(8):825–837. doi:10.1366/11-06365

    CAS  Article  Google Scholar 

  43. 43.

    Das RS, Agrawal YK (2011) Raman spectroscopy: recent advancements, techniques and applications. Vib Spectrosc 57(2):163–176. doi:10.1016/j.vibspec.2011.08.003

    CAS  Article  Google Scholar 

  44. 44.

    Lee PC, Meisel D (1982) Adsorption and surface-enhanced Raman of dyes on silver and gold sols. J Phys Chem 86(17):3391–3395. doi:10.1021/j100214a025

    CAS  Article  Google Scholar 

  45. 45.

    Leopold N, Lendl B (2003) A New method for fast preparation of highly surface-enhanced Raman scattering (SERS) active silver colloids at room temperature by reduction of silver nitrate with hydroxylamine hydrochloride. J Phys Chem B 107(24):5723–5727. doi:10.1021/jp027460u

    CAS  Article  Google Scholar 

  46. 46.

    Sørensen KM, Engelsen SB (2014) Measurement of boar taint in porcine fat using a high-throughput gas chromatography–mass spectrometry protocol. J Agric Food Chem 62(39):9420–9427. doi:10.1021/jf5022785

    Article  Google Scholar 

  47. 47.

    Martens H, Næs T (1991) Multivariate Calibration. John Wiley & Sons, Ltd, Chichester

    Google Scholar 

  48. 48.

    Nørgaard L, Saudland A, Wagner J, Nielsen JP, Munck L, Engelsen SB (2000) Interval partial least-squares regression (iPLS): a comparative chemometric study with an example from near-infrared spectroscopy. Appl Spectrosc 54(3):413–419. doi:10.1366/0003702001949500

    Article  Google Scholar 

  49. 49.

    Savitzky A, Golay MJE (1964) Smoothing + differentiation of data by simplified least squares procedures. Anal Chem 36 (8):1627-1639. doi:10.1021/ac60214a047

  50. 50.

    Barnes RJ, Dhanoa MS, Lister SJ (1989) Standard normal variate transformation and de-trending of near-infrared diffuse reflectance spectra. Appl Spectrosc 43(5):772–777. doi:10.1366/0003702894202201

    CAS  Article  Google Scholar 

  51. 51.

    MacDougall D, Crummett WB (1980) Guidelines for data acquisition and data quality evaluation in environmental chemistry. Anal Chem 52(14):2242–2249. doi:10.1021/ac50064a004

    CAS  Article  Google Scholar 

  52. 52.

    Alharbi O, Xu Y, Goodacre R (2014) Simultaneous multiplexed quantification of nicotine and its metabolites using surface enhanced Raman scattering. Analyst 139(19):4820–4827. doi:10.1039/C4AN00879K

    CAS  Article  Google Scholar 

  53. 53.

    Stewart A, Zheng S, McCourt MR, Bell SEJ (2012) Controlling Assembly of mixed thiol mono layers on silver nanoparticles to tune their surface properties. ACS Nano 6(5):3718–3726. doi:10.1021/nn300629z

    CAS  Article  Google Scholar 

  54. 54.

    Jarvis RM, Goodacre R (2004) Discrimination of bacteria using surface-enhanced Raman spectroscopy. Anal Chem 76(1):40–47. doi:10.1021/ac034689c

    CAS  Article  Google Scholar 

  55. 55.

    Cowcher DP, Jarvis R, Goodacre R (2014) Quantitative online liquid chromatography-surface-enhanced raman scattering of purine bases. Anal Chem 86(19):9977–9984. doi:10.1021/ac5029159

    CAS  Article  Google Scholar 

  56. 56.

    Mabbott S, Correa E, Cowcher DP, Allwood JW, Goodacre R (2013) Optimization of parameters for the quantitative surface-enhanced Raman scattering detection of mephedrone using a fractional factorial design and a portable Raman spectrometer. Anal Chem 85(2):923–931. doi:10.1021/ac302542r

    CAS  Article  Google Scholar 

  57. 57.

    Thygesen LG, Jørgensen K, Møller BL, Engelsen SB (2004) Raman spectroscopic analysis of cyanogenic glucosides in plants: development of a flow injection surface-enhanced Raman scatter (FI-SERS) method for determination of cyanide. Appl Spectrosc 58(2):212–217. doi:10.1366/000370204322842959

    CAS  Article  Google Scholar 

  58. 58.

    Aliaga AE, Osorio-Roman I, Leyton P, Garrido C, Carcamo J, Caniulef C, Celis F, Diaz FG, Clavijo E, Gomez-Jeria JS, Campos-Vallette MM (2009) Surface-enhanced Raman scattering study of L-tryptophan. J Raman Spectrosc 40(2):164–169. doi:10.1002/jrs.2099

    CAS  Article  Google Scholar 

  59. 59.

    Leyton P, Brunet J, Silva V, Paipa C, Victoria Castillo M, Antonia Brandan S (2012) An experimental and theoretical study of L-tryptophan in an aqueous solution, combining two-layered ONIOM and SCRF calculations. Spectrochim Acta A Mol Biomol Spectrosc 88:162–170. doi:10.1016/j.saa.2011.12.023

    CAS  Article  Google Scholar 

  60. 60.

    Combs A, McCann K, Autrey D, Laane J, Overman SA, Thomas GJ (2005) Raman signature of the non-hydrogen-bonded tryptophan side chain in proteins: experimental and ab initio spectra of 3-methylindole in the gas phase. J Mol Struct 735:271–278. doi:10.1016/j.molstruc.2004.11.058

    Article  Google Scholar 

  61. 61.

    Bunte SW, Jensen GM, McNesby KL, Goodin DB, Chabalowski CF, Nieminen RM, Suhai S, Jalkanen KJ (2001) Theoretical determination of the vibrational absorption and Raman spectra of 3-methylindole and 3-methylindole radicals. Chem Phys 265(1):13–25. doi:10.1016/s0301-0104(01)00274-9

    CAS  Article  Google Scholar 

  62. 62.

    Guler Z (2005) Quantification of free fatty acids and flavor characteristics of Kasar cheeses. J Food Lipids 12(3):209–221. doi:10.1111/j.1745-4522.2005.00018.x

    CAS  Article  Google Scholar 

  63. 63.

    Nahar L, Turner AB, Sarker SD (2010) Convenient synthesis of monomeric steroids from steroidal oxalate dimers using flash vacuum pyrolysis (FVP). Turk J Chem 34(3):359–366. doi:10.3906/kim-0907-111

    CAS  Google Scholar 

Download references

Acknowledgments

The authors would like to thank Chief Research Scientist Hanne Maribo (Danish Centre for Pig Research, Axelborg, Axeltorv 3, DK-1609 Copenhagen V, Denmark, http://www.pigresearchcentre.dk/) 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.

Author information

Affiliations

Authors

Corresponding author

Correspondence to Klavs M. Sørensen.

Additional information

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

Electronic supplementary material

Below is the link to the electronic supplementary material.

ESM 1

(PDF 1142 kb)

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

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). https://doi.org/10.1007/s00216-015-8945-2

Download citation

Keywords

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