Fatty acid composition and preservation of the Tyrolean Iceman and other mummies

Abstract

In anthropology, objective parameters to adequately describe storage conditions and the preservation of mummies have yet to be identified. Considering that fatty acids degrade to stable products, we analysed their profile in human mummies and in control samples by gas chromatography coupled to mass spectrometry (GC/MS). Originating from different epochs and civilizations, samples of the Tyrolean Iceman, other glacier corpses, a freeze dried mummy, corpses from a permafrost region, a corpse mummified immersed in water, and a desert mummy were evaluated. Chemometric analysis based on the concentrations of 16 fatty acids revealed the degree of similarity between anthropologic and fresh corpse samples, which was mainly influenced by the content of palmitic acid, oleic acid, and 10-hydroxystearic acid. The presence of 10-hydroxystearic acid was associated with immersion in water, whereas dry mummification was accompanied by high contents of oleic acid. Samples of the Tyrolean Iceman clustered between fresh tissue and those of other glacier corpses indicating the good preservation of this mummy. Thus, environmental post-mortem conditions were associated with characteristic fatty acid patterns suggesting that chemometric analysis of fatty acid contents may add to our knowledge about post-mortem storage conditions and the preservation of human corpses.

Exploration of anthropological specimens by GC‐MS and chemometrics

“…In this section, we summarize our studies on fatty acid concentration profiles measured on tissue samples from different mummies and on fresh reference tissues (Makristathis et al, 1996(Makristathis et al, , 2002 and give additional experimental details. In the following section, we report on new results from chemometric data evaluation.…”

“…In this context, the most intriguing characteristic of fatty acids is their preservation in almost all investigated anthropological specimens. Because they degrade slowly in dependence on environmental conditions, the evaluation of the fatty acid pattern is useful to gather information about the circumstances of the conservation process (Makristathis et al, 2002). Moreover, fatty acids may be conserved in adipocere and are, therefore, often observed at easily detectable concentrations.…”

“…Based on the feasibility of fatty acid speciation in anthropological findings, a completely different approach was recently chosen by our group (Makristathis et al, 2002). The aim of this investigation was to compare the fatty acid patterns of mummies from different epochs and civilizations.…”

“…Analyses of tissue samples were performed as previously described (Makristathis et al, 2002). Briefly, lipid material was saponified in a mixture of 7.5 N sodium hydroxide and methanol.…”

Solid‐phase extraction in combination with GC/MS for the quantification of free fatty acids in adipocere

“…The characterization of the chemical composition and properties of adipocere is a subject of continuous interest and has been reported in a number of studies [1][2][3][4][5][6][7]. Also known as "grave wax" or "corpse wax", this greyish, white caseous material is one of the late post-mortem changes associated with the decomposition of adipose tissue in a body.…”