Steven John Rowland, Paul A. Sutton

The analysis of a number of ad hoc samples of organic beach jetsam by Fourier transform infrared spectroscopy (FTIR), gas chromatography (GC), high temperature GC (HTGC), GC-mass spectrometry (GC-MS) HTGC-MS and derivatisation, is described. Many of these samples were found by members of the public and handed in for analysis in the hope that the material was ambergris. Jetsam ambergris is sometimes valued for its use in perfumery.

None of the materials reported here were ambergris. Rather, several were identified as hydrocarbon waxes and palm oils is various states of degradation. Such materials are common contaminants found on beaches worldwide. Also identified were a number of wood resins and amber-like materials; again, such materials are commonly transported by shipping, but may also have natural origins.

Use of HTGC-MS, in particular, proved advantageous for the analysis of the vegetable oils. Common oil components, such as intact triglycerides, are readily identified by such techniques. Additionally, HTGC-MS allows simultaneous identification of the co-occurring free acids, mono- and di-glycerides in partially degraded samples of vegetable oils. Measurements of the proportions of these latter relative to the triglycerides provides a useful index of the extent of degradation (hydrolysis) of the triesters. Such degradation is common in jetsam samples which may have spent long periods at sea.