Evidence suggests that pottery was used by humans for cooking as long ago as 15,000 to 11,800 years back, and that the pots were used for cooking freshwater and/or marine organisms, primarily fish.

A study published today (April 11) in Nature, based on ancient pottery samples, has another significance — lipids sticking to the “charred surface deposits” of pottery could be successfully recovered and studied despite the pottery being so old.

This is the “oldest pottery” so far investigated for lipid remains. Till now, not much was known about what these early pots were used for by humans. This is despite knowing that pottery production preceded farming and was therefore practised by hunter-gathers. It is a fact that pottery technology “flourished” only in certain groups.

The researchers used molecular and stable isotope analysis to study lipids. Though such methods have been used earlier for studying agricultural remains in vessels that are a few thousand years old, they have been never been put to use for studying pre-agricultural cooking. One reason for this could be that remains of pottery dating back to more than 12,000 years ago are quite rare.

Fatty acids

Lipids extracted from 101 samples from 13 sites from the Incipient Jomon period of Japan were studied. Oliver E. Craig from the University of York, U.K and the first author of the study and others were able to confirm that lipids came from freshwater and/or marine food — they contained medium- and long-chain saturated and mono-saturated fatty acids, isoprenoid fatty acids and alkylphenyl fatty acids.

Of the fatty acids, the alkylphenyl fatty acids provide unequivocal evidence of cooking as they are produced only at a “high temperature” (over 270 degrees C) and as a result of prolonged heating. The fatty acids also rule out the possibility of contamination or accidental presence from the depositional environment.

Also, the fatty acids are “typical of degraded aquatic oils” — hence the source could be only freshwater and/or marine food. Results of carbon isotope analysis further strengthen the findings. However, in one sample, aquatic biomarkers were absent. Instead, the saturated fatty acid found was typical of terrestrial animal fat.

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