Fatty acid specific δ13C values reveal earliest Mediterranean cheese production 7,200 years ago

Abstract

The earliest evidence for cheese production in the Mediterranean is revealed by stable carbon isotope analyses of individual fatty acids in pottery residues from the Dalmatian coast of Croatia. Lipid residue data indicate the presence of milk in the earliest pottery, Impressed Ware, by 5700 cal. BCE (7700 BP). In contrast, by 5200 cal BCE (7200 BP), milk was common in refined Figulina pottery, meat was mostly associated with Danilo ware, cheese occurred in Rhyta, and sieves contained fermented dairy, representing strong links between specific function and stylistically distinctive pottery vessels. Genetic data indicate the prevalence of lactose intolerance among early farming populations. However, young children are lactase persistent until after weaning and could consume milk as a relatively pathogen-free and nutrient rich food source, enhancing their chances of survival into adulthood. Fermentation of milk into yogurt and cheese decreases lactose content. The evidence for fermented dairy products by 5200 cal BCE indicates a larger proportion of the population was able to consume dairy products and benefit from their significant nutritional advantages. We suggest that milk and cheese production among Europe's early farmers reduced infant mortality and helped stimulate demographic shifts that propelled farming communities to expand to northern latitudes.

Fig 1. Location of Neolithic sites with direct residue evidence for dairying in the Mediterranean littoral and cheese in continental Europe [9,10].

Inset: the study area, showing the location of Pokrovnik and Danilo Bitinj on the Dalmatian coast of Croatia.

Fig 2. Probability distributions of calibrated ¹⁴C data of pottery types with associated residues from the sites of Pokrovnik and Danilo Bitinj and the general regional pottery chronology [14,17].

Pottery samples were selected from stratigraphic levels with radiocarbon dates generated on bones and seeds (see S1 Table for details). Examples of pottery types from the Dalmatian Neolithic: a. Impresso Ware; b. Figulina; c. Danilo fine ware; d. Rhyton; e. fragment of a sieve. Photos printed under a CC BY license, with permission from Muzej Grada Šibenika 2018.

Fig 3. Stable carbon isotope compositions of individual fatty acids in lipid residues of animal origin from Neolithic potsherds from Pokrovnik and Danilo Bitinj, Dalmatian coast, Croatia.

Animal origins are indicated based on previous studies by Evershed and colleagues [32,33,36,51]. (See S2 Table for list of pottery samples and biomarker data).

Fig 4. Differences in % lactose, protein, and fat.

A. cattle (Bos taurus); B. goat (Capra hircus); and C. sheep (Ovis aries) dairy products [59,64]; see S3 Table for details.

Fig 5. Partial total ion chromatograms (TICs) of lipid extracts derived from representative ceramic vessels at Neolithic sites on Croatia’s Dalmatian coast.

A, Typical Danilo ware vessel that has molecular distributions indicative of degraded animal (ruminant) fats, such as a narrow distribution of triacylglyerols. B, Impresso style vessel that has molecular residue indicative of degraded fats vis-a-vis animal tissue and leaves. C, Figulina style vessel with molecular distributions indicative of dairy products, such as a wide distribution of triacylglyerols. D, Sieve with typical fermented dairy product lipid distributions, such as abundant branched fatty acids. E, Rhyton vessel that has molecular distributions indicative of firm cheeses, such as shorter-chain fatty acids. br, branched; DAG, diacylglyerol; FFA x:y, free fatty acid that has x carbon atoms and y unsaturations (i.e., double bonds); MAG, monoacylglycerol; TAG, triacylglycerol.