Ergosterol (5, 7, 22-ergostatrien-3β-ol) as a potential biomarker for alcohol fermentation in lipid residues from prehistoric pottery

In this paper we explore the potential use of ergosterol (5, 7, 22-ergostatrien-3β-ol) as a possible biomarker for yeast and alcohol fermentation, applying the analytical technique previously used routinely in Swedish archaeology for the analysis of lipid residue in prehistoric pottery. Taking note on the connection between brewing, baking and agriculture the frequency of vessels showing gas chromatography mass spectrometry traces of this compound in lipid residues from a clearly agricultural Bronze Age/Early Iron Age population was compared with the same signal in a clearly non-agricultural Neolithic foragers pottery population. The result shows a small but statistically significant difference between the two populations, indicating a connection between the presence of ergosterol in lipid residues from pottery and agriculture. The results are also discussed in terms of varying cleanliness, degradation, deposition conditions and contamination. Suggestions for future research include the use of a more sensitive analytical protocol in order to improve detection limits and to include materials from clear agricultural Neolithic vessel populations.