Spatial fingerprinting: horizontal fusion of multi-dimensional bio-tracers as solution to global food provenance problems

Building the capacity of efficiently determining the provenance of food
products represents a crucial step towards the sustainability of the
global food system. Whether it is for enforcing existing legislation or
providing reliable information to consumers, technologies to verify
geographical origin of food are being actively developed. Biological
tracers (bio-tracers) such as DNA and stable isotopes have recently
demonstrated their potential for determining provenance. Here we show that
the data fusion of bio-tracers is a very powerful technique for
geographical provenance discrimination. Based on 90 individuals of Sockeye
salmon that originate from 3 different areas for which we measured 17
bio-tracers, we demonstrate that increasing the combined bio-tracers
results in stronger the discriminatory power. The generality of our
results are mathematically demonstrated under simplifying assumptions and
numerically confirmed in our case study using three commonly used
supervised learning techniques.