Identifying wine and oil production: analysis of residues from Roman and Late Antique plastered vats

Archaeometry, in particular the chemical analysis of the organic residues left by substances, is valuable for identifying the substances that were actually produced and in interpreting the function of these structures. In particular, analyses can be carried out on the plastered coatings of the vats found in these installations. In this paper, we present the results of the analyses of samples of opus signinum (broken ceramics mixed with lime) used to coat vats from installations that were thought to have produced wine or oil. The vats were found in different Roman and Late Roman sites in Italy and in the Balearic Islands and were investigated in order to verify the preservation of the organic residues and their origin. The samples were analysed by gas chromatography/mass spectrometry to identify the presence of oil or wine markers.