Hello, recipe people:
The Fluid Extract of Coca called for in this Coca-Cola formula is not the same thing described in A Treatise On Beverages. If you look in the picture of the Beal formula book on the left hand page, the top of the second column has the recipe for Fluid Extract of Coca used in Coca-Cola. Under the words "To Make F Ext Co", you'll see powdered coca leaf (it says coca-'fol', which is Latin for leaf), kola nut, two other ingredients I can't make out, alcohol, and water. Thus, the Beal recipe book holds its own evidence that what it called "Fluid Extract of Coca" was a compound preparation rather than a single ingredient.
The other thing I would like to bring to your attention is the drops of essential oils. These are being treated as weights, converted to grams; in fact, this is a liquid measure. According to the apothecary system in which this recipe was devised and written (check the left page recipe with its drams and minims), the flavoring is given in drops on the right page and minims on the left; these are interchangeable, and one drop or minim is 1/480 of a US fluid ounce, or about 0.06 ml. As an aside, the same Treatise on Beverages has a whole chapter about essential oils that makes it seem as though the strength of essential oils was very much controllable. It's kind of like the alcohol called for for both the 7X flavoring and the Fluid Extract Coca: the strength is not specified in the recipe, so anyone making it pretty much as to "wing it".
At first I thought the formula on the left was a scaled-down version of the formula on the right, since at first glance it appears to be a one-gallon equivalent of the five gallon recipe. The sugar, water, and lime juice are exact one-fifth equivalents. However, the weights and measurements of other ingredients don't match at all, and the left page has ingredients the right page lacks, including phosphoric acid – which was something Asa Candler is believed to have added to the formula, based on a broad hint given by his son in a private memoir. I'm attaching a document in which I made some general equivalents based on the liquid measures and solid weights on both versions of the formula, side by side.
- Michael Shoshani, Chicago