Characterisation of ‘bog butter’ using a combination of molecular and isotopic techniques

The chemical analyses of “bog buttersâ€� recovered from peat bog of Scotland were performed with the aim of determining their origins. Detailed compositional information was obtained from “bog butterâ€� lipids using high temperature gas chromatography (HTGC) and GC-mass spectrometry (GC-MS). The results indicate the degree to which “bog buttersâ€� have undergone diagenetic alterations during burial to form an adipocere like substance, consisting predominately of hexadecanoic (palmitic) and octadecanoic (stearic) acids. GC-combustion-isotope ratio MS (GC-C-IRMS) was used to determine δ¹³C values for the dominant fatty acids present, revealing for the first time that “bog buttersâ€� were derived from both ruminant dairy fats and adipose fats. The results are compared and contrasted with modern reference fats and adipoceres produced in vitro.