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When Cacao Doesn't Foam
You prepare your cacao with care. The cacao melts, the molinillo turns between your hands, the spices blend… And on the surface?
No foam.
So what?
In Mesoamerican cultures, cacao foam was often sought after and appreciated. Among the Zapotecs, an Indigenous people of southern Mexico, it is still considered the “soul” of the beverage.
That puts quite a bit of pressure on our little foam… But don't worry: if your cacao doesn't foam, it doesn't mean it has lost its soul. Nor does it mean it is of lesser quality. A cacao considered to be of high quality may produce very little foam, while another may produce much more. After all, the very notion of “quality” depends on many different criteria and certainly cannot be measured by a few centimetres of bubbles on the surface of a cup.
Foam tells us something about cacao and how it is prepared. It simply doesn't tell us the whole story.
So, what does it depend on?
First, the gesture. As we explored in our article “The Molinillo: When Cacao Becomes a Dance”, researchers at the Institute of Biotechnology of the National Autonomous University of Mexico (UNAM) observed the molinillo in action using high-speed cameras. They discovered that it does not perform the same function depending on where it is positioned in the beverage.
Near the bottom, it helps disperse the cacao. At mid-depth, it promotes the mixing of water and cacao fats. And as it rises towards the surface, its teeth and grooves meet the interface between air and liquid, introducing bubbles into the beverage. This is where foam forms most easily.
Want more foam? Bring your molinillo slightly closer to the surface. Not particularly interested in foam? Simply keep letting it dance through your cacao.
But the gesture doesn't explain everything. The cacao itself also comes into play.
The formation and stability of foam also depend on the composition of the beverage. The way it is prepared influences the size and stability of the bubbles, as do the ingredients it contains. The fats, proteins and amino acids naturally present in cacao all play a role in these phenomena.
The researchers give a particularly interesting example: pataxte (Theobroma bicolor) (see our article dedicated to pataxte), which contains more fat than common cacao (Theobroma cacao). This composition gives it better foaming properties: the fats help form a kind of “protective network” around the bubbles, allowing them to remain stable for longer.
They also observed, under their experimental conditions, that the cacao content of the beverage could influence the formation of stable foam. In preparations made with cacao powder and water, 100% cacao reduced the surface tension of the water, favouring foam formation.
In other words, not all cacaos foam in the same way. And that's perfectly fine.
And while we watch what is happening on the surface, the molinillo quietly continues its work.
The cacao begins to move again.
The spices blend.
The beverage comes together.
And our hands accompany the gesture.
For us, this is also where something essential lies. The hands that turn the molinillo are connected to the heart: through the gesture, our intention and our energy enter the preparation, foam or no foam.
So, the next time your cacao remains perfectly still on the surface, there's no need to hold it against it.
After all, its soul isn't measured by its foam.
Foam is sometimes visible.
Love isn't always.
Yet it is always there.
***
With you.
Sakara
Sources
Holguín-Salas, A., Corkidi, G. & Galindo, E. (2017). La ciencia detrás de la receta de la abuela para preparar chocolate espumoso usando un molinillo. Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM).
Holguín-Salas, A., López-López, D., Corkidi, G. & Galindo, E. (2015). Foam production and hydrodynamic performance of a traditional Mexican molinillo (beater) in the chocolate beverage preparation process. Food and Bioproducts Processing, 93, 139–147.
Romero, L. (2016). El molinillo, tan eficaz como instrumentos modernos. Gaceta UNAM, 23 May 2016.
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