Genuine or imposter? Authentication of Kakadu plum powders using iso-elemental analyses
Kakadu plum (Terminalia ferdinandiana) is a medium-sized fruiting tree species endemic to northern Australia. As a commercial product, its fruit has multiple health benefits attract consumer interest. This thesis determined the prevalence of food fraud in the e-commerce Kakadu plum market. Stable isotope analysis and elemental profiling were used to evaluate the authenticity of powders purchased from 9 overseas providers. Australian powders were purchased from local enterprises and provided directly from First Nations harvesters. Overseas and Australian powders were found to have distinct isotopic and elemental profiles. All overseas powders showed enriched δ13C values indicating they were fakes, not derived from Kakadu plum. Non-metric multi-dimensional scaling (nMDS) of elements also displayed distinct groupings between Australian and overseas powders, whilst analysis of similarity percentages (SIMPER) differentiated the elemental composition between groups. It was also observed that most overseas powders advertised as Kakadu plum were deceptively labelled as other plant products, potentially to bypass border control screening. Collectively, iso-elemental analyses showed the infiltration of fraudulent overseas-sourced Kakadu plum powders. Given the complexities of multi-national food systems, a collaborative approach incorporating regulation, scientific validation and First Nations oversight may be the most appropriate response to prevent food fraud in the supply chain.
