Real foodborne-illness investigations work exactly this way: epidemiologists start from clustered retail cases and interview distributors backward, one hop at a time, because no single database records a product's full farm-to-fork path.
A live 3D food supply network — farms, processors, distributors and retail stores linked by flowing product lines. Infect a farm and watch contamination dilute and spread downstream in real time, then race to trace it back to its source and issue a recall.
Contamination spreads probabilistically: each batch leaving an infected node carries the source's current infection level, gets tested on arrival at a rate set by QC rigor, and is diluted whenever a node blends stock from several upstream sources — exactly why outbreaks are hard to trace.
Contaminate a farm, watch retail stores start flashing red, then switch to Trace mode and click backward through the real suppliers that shipped the tainted batch. Found the source? Issue a recall from it to block every lane still carrying contamination.
Higher QC rigor doesn't just catch more contaminated batches — it also shrinks the rolling infection level of every node downstream, since caught batches never enter a node's provenance history at all.