Author:

Keywords:

residue analysis, Anglo-Saxon, ceramics, lipid biomarkers, mid-chain ketones, degraded animal fat, brassica leaf wax, fish, marine, beeswax, gas chromatography, mass spectrometry, Social Sciences, Science & Technology, Physical Sciences, Archaeology, Chemistry, Analytical, Chemistry, Inorganic & Nuclear, Geosciences, Multidisciplinary, Chemistry, Geology, Residue Analysis, Ceramics, Lipid Biomarkers, Mid-Chain Ketones, Degraded Animal Fat, Brassica Leaf Wax, Fish, Marine, Beeswax, Gas Chromatography, Mass Spectrometry, ARCHAEOLOGICAL POTTERY VESSELS, IONIZATION MASS-SPECTROMETRY, MADAGASCAR INLAND WATERS, ORGANIC RESIDUE ANALYSIS, BRASSICACEAE SEED OIL, DOUBLE-BOND POSITION, FATTY-ACID PROFILES, LONG-CHAIN KETONES, GC-MS ANALYSIS, ANIMAL FATS, 0402 Geochemistry, 0403 Geology, 2101 Archaeology, 4301 Archaeology

Abstract:

Absorbed lipid residues from twenty-four 7th to 9th century coarseware potsherds from the major Anglo-Saxon trading centre of Hamwic (Southampton, UK) were analysed by gas chromatography mass spectrometry (GC-MS) in order to reconstruct dietary habits of its population. The results show that the vessels were used for preparing ruminant fats and leafy vegetables. In addition, evidence was found for a minor contribution of aquatic foods. Beeswax was found once and most likely relates to a sealing function or to honey. Remarkable features were (i) the isomeric mixture of octadecenoic acid (C18:1 Δ7,8,9,10,11,12,13,14,15,16) and 8- to 16-hydroxyoctadecanoic acid, and (ii) the co-occurrence of C17:1, C19:1 and isoprenoid fatty acids. These features were proposed as biomarkers for ruminant and aquatic food sources, respectively. Furthermore, the carbonyl position distribution in mid-chain ketones was used to identify mixtures of animal and plant derived ketones. The paper highlights the difficulty in interpreting complex lipid signatures which show a mixture of various foods, as observed in the majority of the samples. This was linked to the preparation of stews or the recycling of vessels. The results are considered alongside ceramic usewear data and to existing data relating to environmental remains recovered from the Hamwic excavations.