Use of multi-element profiling for the traceability of Australian pork offal and its relationship to the pork meat physi-trace database

[Truncated abstract] With an increasing demand for high quality product and a rise in the complexity of the globalised food chain the need to rapidly detect and mitigate a health and safety incident in the food industry is essential. As a result, traceability systems are becoming a focus of research and development in many different food sectors. A paper based system known as PigPass is used for traceability of product in the Australian Pork Industry. Such paper based systems are not only time consuming, requiring all individuals to be accurately documented, but with the increasing complexity of the food chain paper based systems are finding it difficult to keep up with the needs of the industry. Furthermore, papers can be fraudulently fabricated with ease and thus validation of trace backs can be slow. To rectify such issues the Australian Pork Industry developed a chemical traceability system known as Physi-Trace. Unique multi-element chemical profiles of pigs from different farms are incorporated into a chemical database that can be used to assign an unknown pig to a geographic region of origin. As chemical signatures are difficult to falsify, chemical traceability is an unambiguous, rapid and robust means of assessing geographic provenance of a suspect sample. However, the current Physi-Trace database consists of multi-element profiles for pork muscle only. Pork offal is a significant export commodity for the Australian Pork Industry with large export markets in Singapore and Hong Kong. Despite the demand for such product, offal is highly susceptible to a multitude of health and safety issues. It is therefore critical for the consumers that any incident can be rapidly traced back to the source and removed from the market. Due to the differential accumulation of elements between different tissue types, direct comparison of chemical profiles in non-lean muscle tissue to the Physi-Trace database is not possible. Therefore, the primary objective of this thesis is to investigate the potential of chemical traceability for pork offal products including tongue, stomach, heart, liver and kidney tissue. Factors that may alter the robustness of chemical signatures at a farm were investigated with particular emphasis on the influence of pig sex, and the change in chemical signature with season. However, for chemical traceability to be a feasible commercial initiative the use of a single traceability database is desirable. Therefore this thesis also outlines the potential to normalise and integrate chemical data for offal into a muscle specific database such as the Physi-Trace system...