If odour or visible residue remains after washing, inspect the container and cleaning workflow instead of guessing the cause. Odour alone does not diagnose biofilm.
Check hard-to-reach surfaces such as gasket channels, corners, shelf joints, drains and removable trays. Photograph cracks, wear or retained moisture.
Remove loose soil first; clean with detergent and rinse. If disinfection is needed, do it after effective cleaning and follow product-label and site instructions for concentration and contact time.
Check fixed points at hard-to-reach areas such as gasket channels and removable parts after cleaning. Record the visual or verification method, result and corrective action.
If ATP or similar rapid tests are used, interpret them as process indicators for specified surfaces; alone they do not prove absence of pathogens or biofilm.
If odour persists, send container ID, product group, cleaning batch and findings to quality. Decide return to use under the approved hygiene procedure.
