Castration of pigs is given an increased attention among consumers and a future scenario might be a stop of castration. A part of the pigs that are not castrated develop a very unpleasant smell, called boar taint, which is unacceptable for the consumer. Therefore the carcasses have to be sorted at the slaughterhouses. So far there is not any generally accepted method for measuring the boar taint compounds: indole, skatole and androstenone. In the future the need for a new sorting analysis that is fast, cheap, robust and exact is present. An optimal method is also capable of measuring all three boar taint compounds.
Proton transfer reaction - time of flight mass spectrometry (PTR-TOFMS) was successfully tested for measuring indole and scatole in the headspace above heated back fat. PTR-MS is useful as a technique for online quantification of volatile organic compounds (VOCs) in air. However, the three boar taint compounds are very lipophilic and will not be present in the headspace above the back fat at the temperature at the slaughterhouse. As the Henry constant is high for androstenone it is not possible to detect the compound under the same conditions as indole and skatole except at very high concentrations. Using a system at the slaughterhouse where a partial sample is taken directly from the carcass and transferred to the lab followed by heating and thereby melting of the back fat and then measuring the indole and scatole in the headspace using PTR-TOFMS gives quick analyses with minimal sample preparation. Initial measurements show good linear correlations between measurements of indole and scatole in the headspace using PTR-TOFMS and extracts of back fat analysed for indole and scatole using DMRI’s reference method based on HPLC. Further work is going on testing the method for measuring androstenone.
1Schäfer, A., 1Kjærsgaard, 1N.C., Borggaard, C., 1Kristensen, L.,
2Sulzer, P, 2,3Jürschik, S.
1DMRI – a division in the Danish Technological Institute, Maglegaardsvej 2, DK-4000 Roskilde, Denmark
2Ionicon Analytik Gesellschaft m.b.H., Eduard-Bodem-Gasse 3, 6020 Innsbruck, Austria.
3Institut für Ionenphysik und Angewandte Physik, Leopold Franzens Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria.