A comparison of methods for establishing fatty acid concentration gradients across potsherds: A case study using Late Bronze Age Canaanite amphorae

Canaanite amphorae fragments in fabrics believed to be associated with the bulk transport of vegetable oils from the fourteenth century BC site of Ama rna, Egypt, have been examined. A comparison is made between solvent extrac tion, saponification and the use of TMTFTH (m-trifluoromethylphenyl)trimeth ylammonium hydroxide, used here for the combined extraction and derivatizat ion of ceramic-absorbed organic residues. Extracts were studied using gas c hromatography and gas chromatography-mass spectrometry. The extraction of f atty acids from small ceramic samples has established concentration gradien ts of absorbed organic matter from the inner to the outer surfaces of the s herds.