Why can a meat grinder develop an odor after cleaning?

Lingering odor usually traces back to fat or protein trapped in the screw chamber, the back of the perforated plate, shaft ends, or seals, often worsened by poor drainage and drying. Clean the machine as usual, then strip it down: where residue collects tells you whether the geometry or the procedure is at fault. If the smell returns, decide between revising the cleaning SOP and modifying components. For volume orders, attach the teardown-and-sanitation standard to the PO and use blade wear as the reference for batch re-checks.