Four millennia of dairy surplus and deposition revealed through compound-specific stable isotope analysis and radiocarbon dating of Irish bog butters

Bog butters are large white or yellow waxy deposits regularly discovered within the peat bogs of Ireland and Scotland. They represent an extraordinary survival of prehistoric and later agricultural products, comprising the largest deposits of fat found anywhere in nature. Often found in wooden containers or wrapped in animal bladders, they are considered to have been buried intentionally by past farming communities. While previous analysis has determined that Irish bog butters derive from animal fat, their precise characterisation could not be achieved due to diagenetic compositional alterations during burial. Via compound-specific stable isotope analysis, we provide the first conclusive evidence of a dairy fat origin for the Irish bog butter tradition, which differs from bog butter traditions observed elsewhere. Our research also reveals a remarkably long-lived tradition of deposition and possible curation spanning at least 3500 years, from the Early Bronze Age (c. 1700 BC) to the 17th century AD. This is conclusively established via an extensive suite of both bulk and compound-specific radiocarbon dates

Compound‐specific stable isotope analysis and radiocarbon dating of Irish bog butters reveal four millennia of dairy surplus and deposition

Bog butters are large white or yellow waxy deposits regularly discovered within the peat bogs of Ireland and Scotland. They represent an extraordinary survival of prehistoric and later agricultural products, comprising the largest deposits of fat found anywhere in nature. Often found in wooden containers or wrapped in animal bladders, they are considered to have been buried intentionally by past farming communities. While previous analysis has determined that Irish bog butters derive from animal fat, their precise characterisation could not be achieved due to diagenetic compositional alterations during burial. Via compound‐specific stable isotope analysis, we provide the first conclusive evidence of a dairy fat origin for the Irish bog butter tradition, which differs from bog butter traditions observed elsewhere. Our research also reveals a remarkably long‐lived tradition of deposition and possible curation spanning at least 3500 years, from the Early Bronze Age (c. 1700 BC) to the 17th century AD. This is conclusively established via an extensive suite of both bulk and compound‐specific radiocarbon dates.European Research CouncilNatural Environment Research Counci

Radiocarbon Dating of Single Compounds Isolated from Pottery Cooking Vessel Residues

From the 17th International Radiocarbon Conference held in Jerusalem, Israel, June 18-23, 2000.We have developed and demonstrated a practical methodology for dating specific compounds (and octadecanoic or stearic acid—C18:0—in particular) from the lipid material surviving in archaeological cooking pots. Such compounds may be extracted from about 10 g of cooking potsherd, and, after derivatization, can be purified by gas chromatography. To obtain sufficient material for precise dating repetitive, accumulating, GC separation is necessary. Throughout the 6000-year period studied, and over a variety of site environments within England, dates on C18:0 show no apparent systematic error, but do have a greater variability than can be explained by the errors due to the separation chemistry and measurement process alone. This variability is as yet unexplained. Dates on C16:0 show greater variability and a systematic error of approximately 100-150 years too young, and it is possible that this is due to contamination from the burial environment. Further work should clarify this.The Radiocarbon archives are made available by Radiocarbon and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform February 202

Marsaglia's lattice test and non-linear congruential pseudo random number generators

Copy held by FIZ Karlsruhe; available from UB/TIB Hannover / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Radiocarbon Dating of Single Compounds Isolated from Pottery Cooking Vessel Residues

From the 17th International Radiocarbon Conference held in Jerusalem, Israel, June 18-23, 2000.We have developed and demonstrated a practical methodology for dating specific compounds (and octadecanoic or stearic acid—C18:0—in particular) from the lipid material surviving in archaeological cooking pots. Such compounds may be extracted from about 10 g of cooking potsherd, and, after derivatization, can be purified by gas chromatography. To obtain sufficient material for precise dating repetitive, accumulating, GC separation is necessary. Throughout the 6000-year period studied, and over a variety of site environments within England, dates on C18:0 show no apparent systematic error, but do have a greater variability than can be explained by the errors due to the separation chemistry and measurement process alone. This variability is as yet unexplained. Dates on C16:0 show greater variability and a systematic error of approximately 100-150 years too young, and it is possible that this is due to contamination from the burial environment. Further work should clarify this.The Radiocarbon archives are made available by Radiocarbon and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform February 202

Characterisation of ‘bog butter’ using a combination of molecular and isotopic techniques

The chemical analyses of ‘bog butters’ recovered from peat bogs of Scotland were performed with the aim of determining their origins. Detailed compositional information was obtained from ‘bog butter’ lipids using high temperature gas chromatography (HTGC) and GC-mass spectrometry (GC-MS). The results indicate the degree to which ‘bog butters’ have undergone diagenetic alterations during burial to form an adipocere like substance, consisting predominately of hexadecanoic (palmitic) and octadecanoic (stearic) acids. GC-combustion-isotope ratio MS (GC-C-IRMS) was used to determine δ13C values for the dominant fatty acids present, revealing for the first time that ‘bog butters’ were derived from both ruminant dairy fats and adipose fats. The results are compared and contrasted with modern reference fats and adipoceres produced in vitro

Determination of the δ 2H Values of High Molecular Weight Lipids by High Temperature GC Coupled to Isotope Ratio Mass Spectrometry

Rationale: The hydrogen isotopic composition of lipids (δ 2Hlipid) is widely used in foodscience and as a proxy for past hydrological conditions. Determining the δ 2H values of large,well-preserved triacylglycerides and other uniquely microbial lipids, such as glycerol dialkylglycerol tetraether (GDGT) lipids, is thus of widespread interest but has so far not been possible due to their size which prohibits analysis by traditional gas chromatographypyrolysis isotope ratio mass spectrometry (GC-P-IRMS).Methods: We determined the δ 2H values of large, polar molecules and applied hightemperature gas chromatography (GC) methods on a modified GC-P-IRMS system. Themethods were validated using authentic standards of large, functionalised molecules(triacylglycerides, TAG), purified reference standards of GDGTs, and compared to δ 2Hvalues determined by elemental analyser pyrolysis isotope ratio mass spectrometry (EA-PIRMS); and subsequently applied to the analysis of GDGTs in a sample from a methaneseep and a Welsh peat.Results: δ 2H values of TAGs agreed within error between different between GC-P-IRMS andEA-P-IRMS, with GC-P-IRMS showing 3-5 ‰ precision for 10 ng H injected. Archaeal lipidGDGTs with up to three cyclisations could be analysed: δ 2H values were not significantlydifferent between methods with standard deviations of 5 to 6 ‰. When environmentalsamples were analysed, δ 38 2H values of isoGDGTs were 50 ‰ more negative than those ofterrestrial brGDGTs.Conclusions: Our results indicate that the high temperature GC-P-IRMS (HTGC-P-IRMS)method developed here is appropriate to determine the δ 2H values of TAGs, GDGT lipidswith up to two cyclisations, and potentially other high molecular weight compounds. Themethodology will widen the current analytical window for biomarker and alimentary lightstable isotope analyses. Moreover, our initial measurements suggest that bacterial andarchaeal GDGT δ 2H values can record environmental and ecological conditions</div