Cereulide on adjacent meat: toxin transfer or de novo production?

Arki et al. provide a useful challenge study of microbial growth and cereulide formation in takeaway pork under different packaging and storage conditions. We highlight a mechanistic ambiguity in the interpretation of cereulide detected on meat placed on Bacillus cereus-inoculated pasta. Because viable B. cereus also transferred to the meat, the experiment cannot distinguish physical transfer of preformed cereulide from bacterial transfer followed by de novo toxin synthesis. This distinction is important because cereulide formation depends on food matrix and environmental conditions. In addition, recovery rates above 100% warrant caution when relating absolute bioassay-derived concentrations to intoxication levels, and toxin measurements only at 24 h limit kinetic inference. Purified-toxin controls, non-emetic B. cereus controls, time-resolved paired measurements, and targeted LC-MS/MS confirmation would resolve these pathways while preserving the study's central food-safety message.