061212-055
Looking into Pots: To find out what pots wree used for in the past, the chemicals absorbed into the vessel walls during cooking are analysed. The most common organic chemicals that come from pottery are lipids, the fats, waxes, and oils found in a wide range of food and other natural products such as beeswax and birch bark tar. To extract lipids from pottery, a small amount of the pot is ground up and mixed with an organic solvent to dissolve any compounds lodged in the pores or stuck on the surface. Different lipids are then separated out by a process called gas chromatography and the chemical structures of the lipids are determined by mass spectrometry. These techniques are very similar to those used to measure the amound of satured and unsaturated fats in the food and drinks we buy. A Coppergate case Study: To find out what the viking Age people at Coppergate were eating, the inside rim area of a 16th century ceramic pot from this site was ground up. Residues often form around the top of a pot, particularly when foods are boiled, as the lipids rise to the surface and leave a mark where the original level of the liquid was, like the tide mark left after a bath. An extract of this sample contained trace elements (just several parts per million) of saturated fatty acids and cholesterol, derived from animal fats such as beef, lamb, and pork or perhaps ever milk. The sample also contained typical lipds of leaf wax, with a pattern that closely matched the Brassica gleracea (cabbage) family. this may have been leafy cabbage of a kale-like plant, a coarser version of the dense headed cabbages known today. Results from this small study suggest therefore that this pot had an everyday use, stewing meat and leafy vegetables to make a tasty and nutritious broth. Lipid analysis is very important when archaeologists want to know not just the species of foods eaten in the past but what other products people made from natural resources such as dairy foods, beeswax, and res
061212-055
Looking into Pots: To find out what pots wree used for in the past, the chemicals absorbed into the vessel walls during cooking are analysed. The most common organic chemicals that come from pottery are lipids, the fats, waxes, and oils found in a wide range of food and other natural products such as beeswax and birch bark tar. To extract lipids from pottery, a small amount of the pot is ground up and mixed with an organic solvent to dissolve any compounds lodged in the pores or stuck on the surface. Different lipids are then separated out by a process called gas chromatography and the chemical structures of the lipids are determined by mass spectrometry. These techniques are very similar to those used to measure the amound of satured and unsaturated fats in the food and drinks we buy. A Coppergate case Study: To find out what the viking Age people at Coppergate were eating, the inside rim area of a 16th century ceramic pot from this site was ground up. Residues often form around the top of a pot, particularly when foods are boiled, as the lipids rise to the surface and leave a mark where the original level of the liquid was, like the tide mark left after a bath. An extract of this sample contained trace elements (just several parts per million) of saturated fatty acids and cholesterol, derived from animal fats such as beef, lamb, and pork or perhaps ever milk. The sample also contained typical lipds of leaf wax, with a pattern that closely matched the Brassica gleracea (cabbage) family. this may have been leafy cabbage of a kale-like plant, a coarser version of the dense headed cabbages known today. Results from this small study suggest therefore that this pot had an everyday use, stewing meat and leafy vegetables to make a tasty and nutritious broth. Lipid analysis is very important when archaeologists want to know not just the species of foods eaten in the past but what other products people made from natural resources such as dairy foods, beeswax, and res