Immunological detection of denatured proteins as a method for rapid identification of food residues on archaeological pottery Jaroslav Pavelka a , Ladislav Smejda b, c, * , Radovan Hynek d , Stepanka Hrdlickova Kuckova d a Centre of Biology, Geosciences and Environmental Education, University of West Bohemia, Univerzitni 8, 30614, Plzen, Czech Republic b Department of Archaeology, University of West Bohemia, Univerzitni 8, 30614, Plzen, Czech Republic c Department of Ecology, Czech University of Life Sciences Prague, Kamycka 961/129,165 00, Praha 6-Suchdol, Czech Republic d Department of Biochemistry and Microbiology, University of Chemistry and Technology, Prague, Technicka 3,166 28, Prague 6, Czech Republic article info Article history: Received 25 June 2015 Received in revised form 18 June 2016 Accepted 11 July 2016 Keywords: Immunological assays ELISA Food Organic residues Archaeological pottery Past diet patterns abstract Our understanding of human diet in different periods of history can be enhanced by investigating direct evidence represented by accidentally preserved food remains found on pottery. So far, this task has been accomplished by the application of gas chromatography/mass spectrometry, often in combination with stable isotope analysis. These methods require specialised laboratories and their cost prevents wider penetration into the daily practice of archaeology and related disciplines. We have tested commercially available immunochromatographic kits for this task, which are designed to detect contaminants and allergens in the modern food industry. Unlike the previously published studies on archaeological ma- terial, we focus specifically on the identification of damaged and denatured proteins, which correspond better to the state of preservation of proteins in desiccated and carbonised organic residues that have survived from antiquity. We report the first successful qualitative detection of bird eggs, animal meat, milk (and species of origin), and to some extent also the presence of plant food, especially cereals and hazelnuts. The immunoassay is a methodology that is well suited for use in the field and resource-poor environments, so it is ideal for most archaeological excavations and museums. With necessary caution, the results can be used as a proxy for human diet in the past and reconstructions of anthropogenically modified environments. © 2016 Published by Elsevier Ltd. 1. Introduction It is occasionally possible to find ancient food residues attached to archaeological pottery, usually in the form of accidentally desiccated or charred organic material. Analysis of such remains is highly desirable, as the results may suggest the final purpose of a particular vessel, before it went out of use and was discarded (Pollard et al., 2007 :22e23). The significance of this type of research is twofold. It may reveal a cultural association between certain types of pots and meals that were cooked in them and possible variations in the use of ceramic inventories of households. Secondly, it provides data on human diet in specific cultural and social contexts, if these can be recognised from the archaeological record. Alternatively e and complementarily e approaches that help study subsistence on the basis of archaeological finds include the compositional analysis of animal bones and finds of preserved botanical macrofossils. Well preserved bones and plant remains are not ubiquitous on ancient sites, depending heavily on local taph- onomic conditions (Dincauze, 2000; van der Veen, 2007; Wright, 2003). Indirect approaches, which can detect only broad types of diet, include complex dental analysis and the analysis of stable isotopes in human bones (Day, 2013; Forshaw, 2014; Klippel, 2001; Landon, 2005; Reitsema et al., 2010). For a detailed analysis of carbonised food residues usually found as attachments on the surface of cooking vessels, there are currently two dominant approaches available, each with its own pros and cons. The more widespread method is the analysis of lipids through the identification of fatty acids by gas chromatography-mass spectrometry (GC-MS), sometimes coupled with the analysis of carbon stable isotopes, which allows the distinction between ruminant and non-ruminant fat in remains of animal origin (Cramp et al., 2014; Dudd et al.,1999; Regert, 2011; Salvini et al., 2008). A possible advantage of the study of lipids * Corresponding author. Department of Archaeology, University of West Bohemia, Univerzitni 8, 30614, Plzen, Czech Republic. E-mail address: smejda@kar.zcu.cz (L. Smejda). Contents lists available at ScienceDirect Journal of Archaeological Science journal homepage: http://www.elsevier.com/locate/jas http://dx.doi.org/10.1016/j.jas.2016.07.004 0305-4403/© 2016 Published by Elsevier Ltd. Journal of Archaeological Science 73 (2016) 25e35