What was found
AFTER TAKEOFF, FLIGHT ATTENDANT EXPERIENCED AN UNUSUAL SMELL IN FWD CABIN. AS A PRECAUTIONARY MEASURE, FLIGHT CREW ELECTED TO RETURN TO MAIN MAINTENANCE BASE. INSPECTED AIRCRAFT, OPERATED BOTH ENGINES, INSPECTED APU, AIR CONDITIONING DUCTING IN GALLEYS. NO DEFECTS NOTED. AS PRECAUTIONARY MEASURE, REPLACED THE LT AND RT COALESCER BAGS PER MM21-00. SYSTEM OPS CHECKED GOOD.