A biological procedure was devised to evaluate de Ruyter and Brunet's heat transfer computer simulation for sterilizing particulate foods in a swept surface heat exchanger (SSHE). Turkey cubes measuring 12.7 mm were inoculated with spores of Clostridium sporogenes PA3679, using a so‐called “knotted string” method. Inoculated cubes were introduced into a viscous starch medium and thermally processed in a SSHE to a fractional survivor endpoint. Processed product was packaged aseptically, incubated and examined for survivors. Biological sterilization values calculated from the inoculated packs support the validity of the simulation. Also, a novel method was devised to measure particle residence times in hold tubes using electro‐magnetic induction.