Chemical Alteration and Use of Beeswax Through Time: Accelerated Ageing Tests and Analysis of Archaeological Samples from Various Environmental Contexts

Abstract

In order better to interpret the chemical composition of ancient organic residues and artefacts containing beeswax, the degradation of this raw material was accelerated in the laboratory by controlled heating. During the course of degradation, deposits were condensed above the beeswax. Both degraded beeswax and these deposits were analysed. These experiments definitively proved that n‐alkane depletion is due to a sublimation process that depends on the molecular weight of these hydrocarbons. The formation of benzoic and cinnamic derivatives due to the degradation of flavonoid precursors initially present in beeswax has also been highlighted for the first time. The analysis of samples from Neolithic and Roman periods led to the identification of beeswax characterized by different degradation patterns linked to their environmental context.

Widespread exploitation of the honeybee by early Neolithic farmers

“…n Alkanes were detectable but the distribution is skewed towards the higher homologues compared to that expected in fresh beeswax, although such distributional changes are frequently seen in historical and archaeological beeswax, assumed to arise by sublimation during ageing or heat treatment 10 . The tentative identification of this very early beeswax residue at Çatalhöyük is supported by the discovery of a strik ing depiction of a honeycomb like pattern painted on a wall at the site 21 .…”

“…Although the most obvious reason for exploiting the honeybee would be for honey, a rare source of sweetener for prehistoric people, bees wax would likely have been an equally important material for various technological, ritual, cosmetic and medicinal applications 10 . Indeed, beeswax has been regularly detected in later archaeological and historic periods in lipid extracts from the fabric of unglazed pottery vessels 11 where it is assumed to be a residue of honey use in cooking, or from the use of vessels for processing wax combs [12][13][14] , with beeswax being absorbed through repeated contacts.…”

“…The hydrophobic nature of beeswax makes it relatively resistant to degradation. Hence, if protected from extensive microbial attack and/or exposure to high temperatures during anthropogenic manip ulation, the aforementioned chemical characteristics can be used in assessing its presence 10,19 (Figs 1 and 2).…”

Organic Residues in Archaeology: The Highs and Lows of Recent Research

“…The effects of degradation on the chemical composition of organic materials during their use and subsequent burial is reasonably well understood (3,4,6,8,(26)(27)(28)(29)(30). However, the increasing importance of isotopic analysis of various types of materials raises the question of whether isotopic values are stable under burial conditions.…”

Pastoralist Foodways Recorded in Organic Residues from Pottery Vessels of Modern Communities in Samburu, Kenya

“…Dudd and Evershed 1998;Evershed et al 2002;Copley et al 2003;Evershed et al 2008;Dunne et al 2012;Debono Spiteri et al 2016). Likewise, aquatic products (Patrick et al 1985;Hansel et al 2004;Craig et al 2007;Hansel and Evershed 2009;Shoda et al 2017), plant oils and waxes denoting vegetable and plant oil consumption/ processing (Evershed et al 1991;Copley et al 2001a;Copley et al 2001b;Reber et al 2004;Copley et al 2005;Cramp et al 2011;Dunne et al 2016) and beeswax (Heron et al 1994;Charters et al 1995;Evershed et al 1997b;Regert et al 2001;Evershed et al 2003;Roffet-Salque et al 2015), resins, tars and bitumen (Beck et al 1989;Mills and White 1989;Evershed et al 1997a;van Bergen et al 1997;Urem-Kotsou et al 2002;Stern et al 2003;Buckley et al 2004;Stern et al 2008;Connan et al 2013;Brown et al 2014: Brettell et al 2014 have been identified in connection with a wide range of technological and cultural activities. On a broader scale, lipid residue analyses can provide insight into the domestication of plants and animals, the development of animal husbandry practices and ecological and environmental changes through time (Evershed 2008b;Evershed et al 2008;…”