What was found
FLT#1568, PUJ-JFK. 'ON TAXI OUT, INFLIGHT CALLED UP REPORTING A PUNGENT ODOR. AGREED TO TAKE OFF TO SEE IF IT WOULD DISSIPATE. NO SMELL COMING FROM A/C OUTLETS. CALLED UP AGAIN ON CLIMB & CRUISE. ODOR WAS ONLY NOTICED IN GALLEY AND THE FIRST 4 ROWS. RAN ODOR PROCEDURE IN FCOM 1. THE SMELL DISSIPATED AROUND 2120 [Z] AND THEN CAME BACK DURING DESCENT AROUND 2145 [Z]; ODOR WAS ONLY OBSERVED ON ROWS 1-4, AND THE PILOT COULD NOT CONFIRM ODOR. ODOR REPORTED MORE AS PUNGENT SMELL AND NOT DIRTY SOCKS/OIL. COMPLIED WITH INFO NOTICE 2017-TO15 SECTION B[2]. THE AIRCRAFT IS OK FOR SERVICE. DUE TO ODOR BEING IN ROWS 1-4 SUSPECT EXTERNAL SOURCE, POSSIBLE BAGGAGE, OR CUSTOMER. AS PRECAUTIONARY, PERFORMED LEVEL A ECS DECONTAMINATION PER AMM 21-00-00-615 OPERATED PACK WITH ENGINE BLEED FOR 30 MIN. NO ODOR PRESENT.'