Distinguishing plant oils from animal fats in the archeological record of the eastern Mediterranean by isotope ratio mass spectrometry (CAT#: STEM-ST-0027-LJX)

Introduction

Distinguishing animal fats from plant oils in archaeological residues is not straightforward. Characteristic plant sterols, such as β-sitosterol, are often missing in archaeological samples and specific biomarkers do not exist for most plant fats. Identification is usually based on a range of characteristics such as fatty acid ratios, all of which indicate that a plant oil may be present, none of which uniquely distinguish plant oils from other fats. Degradation and dissolution during burial alter fatty acid ratios and remove short-chain fatty acids, resulting in degraded plant oils with similar fatty acid profiles to other degraded fats. Compound-specific stable isotope analysis of δ(13)C(18:0) and δ(13)C(16:0), carried out by isotope ratio mass spectrometry (IRMS), has provided a means of distinguishing fish oils, dairy fats, ruminant and non-ruminant adipose fats.