Stable isotope and multi-element analysis coupled with DD-SIMCA for verification of Slovenian pork origin and Krškopolje pig authenticity

Pig farming in Slovenia has a long tradition and is known for producing high-quality pork; however, almost two-thirds is imported, raising concerns about mislabelling. In addition to modern Slovenian breeds (MB), the Krškopolje pig (KP), the only preserved autochthonous pig breed in Slovenia, is highly valued for its high-quality, marbled meat, which is sold at a premium price. This study presents the first Slovenian pork database on stable isotope (δ2H, δ18O, δ13C, δ15N, δ34S) and elemental composition, comprising 148 samples: 107 authentic Slovenian pork samples (MB and KP), 22 foreign samples, and 19 samples labelled as Slovenian collected from supermarkets. We investigated the geographical origin of modern-breed pork and the breed authenticity of Krškopolje pig pork using DD-SIMCA class modelling. The established DD-SIMCA models showed high sensitivity (97 % and 96 %) and specificity (100 % and 89 %), respectively. When applied to commercial pork products labelled as Slovenian, 79 % of the samples exhibited isotopic and elemental profiles that differed from the authentic Slovenian reference class established in this study. These findings demonstrate the potential of combined isotope–elemental profiling coupled with DD-SIMCA modelling as a complementary tool for pork origin authentication and traceability verification. However, classification results indicate consistency with the reference class rather than legal origin status and should therefore be interpreted accordingly