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We hereby investigate the pitch used for coating three Roman amphorae from San Felice Circeo (Italy) through a multidisciplinary study. The identification of molecular biomarkers by gas chromatography—mass spectrometry is combined with archaeobotanical evidence of pollen and plant tissues of Vitis flowers. Diterpenic chemical markers together with Pinus pollen and wood revealed Pinaceae tar coating. Aporate 3-zonocolpate pollen, identified as Vitis, together with tartaric, malic and pyruvic acids elucidate the grape-fermented nature of the content. Our conclusions open new consideration on the use of grape derivatives that cannot be supported by traditional analytical methods. Based on the finds of aporate Vitis pollen, found also in local modern and Middle Pleistocene samples, we hypothesize the use of autochthonous vines. The presence of a medicinal wine (historically reported as oenanthium) is also considered. We interrogate Vitis pollen capacity to target grapevine domestication, thereby providing innovative tools to understand such an important process. We anticipate our study to encourage a more systematic multidisciplinary approach regarding the analyses of wine amphorae.

International audience; With the aim of addressing the impact of extractive protocols in molecular characterization of ceramic content, sixteen archaeological shards and waterproofing coatings of Roman amphorae were studied to compare the extractive capacities of protocols prevalently mentioned in wine amphorae analysis. A microwave-assisted protocol is developed in order to esterify grape-derivative markers from archaeological pitch and shard. Gas chromatography-mass spectrometry is used to highlight the great capacities of a two-step protocol that combines organic extraction with BF3-etherate complex butylation applied on archaeological shards. Instead, simultaneous alkaline fusion and direct-resin acid-catalyzed butylation are favored for the characterization of waterproofing material. The identification of tartaric acid, together with succinic, fumaric pyruvic and syringic acids provide valuable insights on the archaeological grape-derivative content, possibly wine. Diterpenic markers highlighted Pinus pitch and wood tar, originally used to waterproof the amphorae. Since markers are reliable tools in organic residue analyses, protocols exhibiting high extractive capacities are favored to avoid false conclusions drawn through the absence of markers.

In this paper, we propose the application for the first time in the Mediterranean area of the combination of the study of chemical residues in floors and ceramics, with the aim of providing information about the activities carried out in archeological buildings. We chose the Garum Shop at Pompeii to test the method. In fact, due to the peculiarity of this archeological context, it provided an ideal case in which the activities performed are in part known, and the ceramic vessels recovered are still in situ. Floor samples were studied by means of spot tests developed in Mexico aimed at identifying the presence of phosphates, fatty acids, and protein residues, while the organic residues preserved in the ceramic matrix of amphorae, dolia, and other ceramic vessels were studied by gas chromatography coupled with mass spectrometry. Moreover, we integrated the data obtained with specific studies directed at better identifying the solid residues found inside two of the amphorae studied: botanical studies of fruit stones recovered in a Dressel 20 amphora and the characterization of the lime preserved in an African amphora. The research allowed for the identification of the traces of some of the activities performed, such as cooking and producing garum in the floors of the building, and the use and re-use of amphorae and dolia before the Vesuvian eruption.

Research already carried out on the use of the recently patented electroless nickel ceramic codeposition technique as a method of manufacturing solid oxide fuel cell (SOFC) electrodes has thus far indicated that, while functional electrodes can be manufactured by the technique, for optimum performance of the cell, amplification of the ceramic content of the coatings is still required.By mainly employing external agents such as surface active agents (surfactants) and magnetic fields (in a bid to aid ceramic particle stability), this research focused on the prospect of increasing the ceramic content of cermets co-deposited for use as SOFC electrodes. A total of 137 co-deposited samples were produced from different bath compositions.As a prelude to the study, the interactions between the ceramic powders used (yttria stabilised zirconia (YSZ) / lanthanum strontium manganate (LSM)) and the medium for the deposition process – the electroless nickel solution, were investigated by zeta potentiometry and ultraviolet-visible spectroscopy techniques. The results obtained from the studies led to a variation of a series of fundamental plating factors such as the ceramic bath loading and particle size of the powders. While the former was found to yield the highest ceramic content in the coating at a bath loading of 50 g/l, variation of latter notably produced mixed results.With the introduction of surfactants, it was noted that above the surfactant’s (sodium dodecyl sulphate) critical micelle concentration, the incorporation of ceramic particles (YSZ) into the nickel matrix steadily increased to as much as 60 volume %. An inverse relationship was though found to exist between the coating thickness and the surfactant’s bath concentration.Uniform coatings were found to be associated with low magnetic field strengths while although increased magnetic field strengths positively resulted in the amplification of particle incorporation into the coating, a lack of cohesion between the coating and the substrate – as indicated by coating flake-off, was observed at such strengths. It is suggested that because the magnetic flux was more dominant than the normally ionic plating mechanism, the particles co-deposited under the influence of a high magnetic field were relatively unstable after the coating process.Since LSM is alkaline in nature this work confirms that future research on the application of electroless nickel ceramic co-deposition as a method of manufacturing SOFC cathodes, be focused on the use of alkaline electroless nickel baths rather than the acidic solutions, which better suite YSZ particles.