The trick to grinding cacao on the metate (grindstone).

Now grinding seeds is always hard so it’s no wonder that Beatrice resorted to the coffee grinder, especially because she was working with a pestle and mortar, which, even if it is used to shear, is not as effective as a grindstone.

Even if you have a grindstone, though, even if you know how to grind, it’s tricky to work with cacao because as you grind the mixture seizes up.  The time-honored Mexican way of dealing with this is to heat the grindstone.

Here in this classic engraving from Nicolás de Blegny´s 1687 Le bon usage du thé, du caffé et du chocolat an aproned gentleman is shown gingerly wielding the mano of the grindstone.  Underneath you can just see the brazier that is warming the stone. Cristina Potters, always informative on Mexican customs,  has a series of photos showing Doña Lupe of Patzcuaro in the state of Michoacán in Central Mexico grinding beans.  Since Doña Lupe says she processes 20 to 30 kilos a day, I suspect there are actually a number of other (and perhaps less elegantly dressed) women helping her.

Because given the hard work of grinding as I discovered here or as Lesley Téllez is now discovering, grinding over a heated grindstone is work indeed.

Now back to some archaeology.  A recent article in Nature pushed back the origin of chocolate consumption to 500 BC.

The first chemical evidence of cacao use came about 15 years ago after the analysis of residue from a vessel found at the Mayan site of Rio Azul in northeastern Guatemala and belonging to the Early Classic period of Maya culture—approximately A.D. 460. But Michael Coe, co-author of The True History of Chocolate, believes based on a slew of evidence, some linguistic, that the roots of chocolate go much further back to the great Olmec civilization, which preceded the Maya.

Mayan teapots have always fascinated Terry Powis, an archaeologist at the University of Texas at Austin, which is how his investigation began. “Spouted vessels are very distinct from other Mayan ceramics and quite rare, typically associated with elite burials,” he explained.

Fortunately for Powis, fourteen such vessels were excavated in 1981 from a site at Colha, which lies close to the Caribbean coast in northern Belize, and have since been housed at the University of Texas, Austin. The Maya occupied Colha, which is known for its production of stone tools and its Preclassic spouted vessels, continuously from about 900 B.C. to A.D. 1300.

He scraped residue from the vessels and sent the samples to W. Jeffrey Hurst, who has a delicious job as an analytical biochemist at the Hershey Foods Technical Center in Hershey, Pennsylvania.

Using “high performance liquid chromatography coupled to atmospheric-pressure chemical ionization mass spectrometry,” Hurst analyzed all the samples. The first instrument separates all the components of the mixture and the other measures the molecular weight of each. Cacao is a blend of more than 500 chemical compounds. Of this tasty compendium the signature chemical is a compound called theobromine—the chemical marker of cacao.

Of the 14 samples analyzed, 3 were positive for theobromine, “chocolate, that is,” said Powis.

OK, well and good.  Theobromine in pots from 500 BC.  The trouble is that, if my memory serves, metates on legs do not appear until the Classical Period in Mexico, that is, until around 200 BC.

So whether you take Powis´s proven 500 BC or Michael Coe´s plausible earlier date of something close to 1000 BC, how were they grinding the chocolate? Or were they?  Were they just simply making nibs?

I’m sure some archaeologist has addressed this.  I just haven’t run across it.

• ← The long road from cacao to chocolate
• Speculations, please: the griddle-seared pastry (warka-popiah) across Eurasia →