What was found
CLT - DESCENDING THROUGH 9,000 FEET, CREW REPORTED AN UNUSUAL ODOR THAT CAME ON STRONGLY. SMELLED LIKE BURNT OIL. ODOR DISAPPEARED/DECREASED ON TAXI-IN. MAINTENANCE ACCOMPLISHED JOB CARD 03L10025001, OIL/SMELL IN CABIN - OIL LEAK CHECK. NO LEAKS FOUND (APU, ENGINES, ACM'S). RAN EACH PACK INDIVIDUALLY WITH APU, ENGINE NR 1 AND ENGINE NR 2. NO SMELLS DETECTED. REMOVED AND REPLACED AIR RECIRCULATION FILTER PER MM 21-21-23. WHILE CHECKING FOR ELECTRICAL SMELLS, FOUND TWO SPOILED FISH DINNERS IN FORWARD GALLEY OVEN. CLEANED OVEN. NO HISTORY FOR 120 DAYS. AIRCRAFT OK FOR SERVICE.