Lipid residue analysis of Chinese ritual bronzes: Methodological and archaeological implications

Abstract

Ritual bronze vessels are the most important artefacts in the Chinese Bronze Age. Based on typological studies, different vessel types were linked with specific sacrificial offerings, for example meat, crop and alcohol, which further implied vessel functions and ritual traditions in early Chinese history. However, direct evidence of the original food and drink contents in the bronze vessels was largely missing and information was mostly inferred from casting inscriptions and historical records. To test the potentials of lipid residue analysis in ritual bronzes, we selected sediments associated with 17 bronzes from the Dahan Cemetery, Shandong Province, 11 bronzes from the Sujialong Cemetery and 1 from the Yangjiaping Cemetery, Hubei Province. Samples were collected from different positions of the vessels and characteristic types of bronzes to compare their lipid profiles. The results showed that solvent extraction yielded the highest concentrations of steroids at Dahan, while alkaline saponification recovered the most abundant lipid classes at Yangjiaping and Sujialong. Different extraction methods may be selected based on burial environments and research objectives. At Dahan, the lipid profiles from sediments attached to the interior bottom of the vessel which mixed with corrosion products displayed distinctive features in contrast to the lipids from environmental background, demonstrating their potentials in indicating original foodstuffs. The lipid results from Sujialong exhibited larger contributions from the burial environment. Sacrificial bronze vessels generally displayed different lipid compositions associated with their food and alcohol contents, showing the indicative significance of bronze residues. Long-chain fatty acids and plant steroids dominated the lipid profiles of Dui, Dou, Gui, Li and Fu, which have traditionally been considered as food containers, although the origins of plants cannot be confirmed. The presence of miliacin in the bronzes of Hu and Zunfou at Dahan points to the use of millets, probably as alcoholic beverage. At a later stage, fruit drink appeared in Houlou at Yangjiaping.