Potential Use of Stable Isotope and Multi-element Analyses for Regional Geographical Traceability of Bone Raw Materials for Gelatin Production

Abstract

Geographical authentication of bone raw materials to determine whether they come from non-epidemic areas and natural pastoral areas is critical to quality control, food safety, and brand protection of gelatin. The establishment of an effective traceability method independent of paper records has become increasingly urgent. Therefore, the potential of the stable isotope and multi-element analyses for distinguishing the geographical origin of bone samples from various provinces in China was investigated. The C, N, and H isotopic compositions and the contents of 18 elements in bovine bone samples were studied by isotope ratio mass spectrometry (IRMS), inductively coupled plasma mass spectrometry (ICP-MS), and inductively coupled plasma optical emission spectrometer (ICP-OES), combined with one-way analysis of variance (ANOVA), principal component analysis (PCA), and linear discriminant analysis (LDA). It was shown that the values of δ13C, δ15N, and δ2H as well as the contents of 16 of the 18 elements in bone samples were significantly different among the regions. A total correct classification rate of 95.7% and 100% was obtained by the stable isotope traceability method and multi-element traceability method, while the cross-validation rate was 91.5% and 97.9%, respectively. It was concluded that both stable isotopes and mineral elements can be good indicators for tracing the geographical origin of bone raw materials. Due to the minor difference in the discrimination accuracy of these two methods, it is preferable to establish traceability models using stable isotope method in practical work considering economic feasibility and efficiency.