As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LHR - CREW REPORTED ELECTRICAL ODOR IN MID CABIN GALLEY. GALLEY EMERGENCY POWER CONTROL SWITCH TURNED OFF ODOR THEN DISSIPATED. FLIGHT LANDED LHR WITHOUT INCIDENT. FOUND ON INVESTIGATION OVENS 4A/B PRODUCING ODORS. REPLACED OVEN 4A/B. SYSTEM GROUND CHECK NORMAL OPERATION.