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Food remains

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Description

Food remains are an important culture-historic and archaeological source of information to reconstruct the life of our ancestors. The available food supply also allows us to draw conclusions about possible climate change. If the food remains cannot be clearly identified macroscopically or using techniques of visualization because they are burnt or largely decayed, etc., element or isotope analyses may help identifying the material and therefore food components. Since plants are usually annual plants and the animals raised for dietary purposes only have short lifespans, radiocarbon dating of food remains provides a time frame for the processing and origin of the food.

Sample properties

The nature of food remains can be quite different. Sometimes there are only tiny adhesions on pots, bowls or in the ground. Ideally, it is possible to visually identify what the food remains are (corn, nuts, peas, etc.). If several analyses are to be carried out, such as 14C dating and stable carbon and nitrogen isotope analysis, please submit a correspondingly large quantity of the sample.

14C-dating

For radiocarbon dating, the sample material must be decontaminated, regardless of its consistency. In the case of macroscopically detectable food residues such as peas, nuts or corn grains, a whole grain or nut is sufficient. In the case of a crumbly mass, approx. 100 mg of the material should be available, since pre-treatment may cause considerable loss, depending on consistency and state of preservation. In the case of fatty films and similar adhesions or material seeping into the soil, only a component-specific analysis is meaningful, for which approx. 100-200 mg of material should also be provided. Please contact the laboratory in case of considerably smaller sample quantities.

Carbon and nitrogen isotope analysis

Carbon and nitrogen isotope analysis of the total material can give a rough indication of the material that is preserved as food crusts in vessels, whereas component-specific analyses are usually more informative.

Carbon and nitrogen isotope analyses are generally possible for a sample size of less than 10 mg. However, the required sample quantity varies depending on the C and N contents of the material and the demands on the analyses (multiple determinations, techniques of decontamination), so that initial weights between 50 and 100 mg are generally recommended.

Please contact the laboratory in the respective case.

Methods

Infrastructure

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