Methodological Approach for Identification of Organic Residues Preserved in Roman Amphorae

Several studies have focused on local workshops in the Picton territory, the western center of Gaul. Picton potters notably reproduced the forms of amphorae imported from the north of Spain (Pascual 1, Dressel 2/4), or from the Narbonensis province (Gauloise 4 and 5). To ascertain to what end these amphorae were manufactured in the region, the chemical study of the organic residues left in the vessels was undertaken. An analytical protocol with a two-step analysis is proposed herein. Firstly, py-GCMS of sherds gives rise to a global print of the different compounds present in their pores, and permits to choose an adapted protocol of extraction for further GCMS analysis. In the present work, the methodology is tested using amphorae sherds originating from local workshops-hence never used-that we soaked in a wine of known composition, before analyzing them via both GCMS and py-GCMS showing the complementary of these approaches and their efficiency in the study of archaeological organic residues originating from amphorae found in consumption sites in Poitiers .