The Original
The following recipe is supposedly the original coca-cola recipe that was unearthed in an old notebook that belonged to coca-cola inventor J. S. Pemberton. This recipe was largely substantiated by a second source who had been employed by coca-cola in the USSR during the 1940's. The recipe and account of how it was found is detailed in the book For God, Country and Coca-Cola by Mark Pendergrast (see Bibliography).
Ingredients:
1 oz Citrate Caffeine 30 lbs. Sugar
3 oz Citric Acid 4 oz F.E. Coco*
1 oz Ext. Vanilla 2.5 gal.Water
1 Qt. Lime Juice Caramel - sufficient
2.5 oz Flavourings (see below)
*It seems that "F.E. Coco" refers to a fluid extract from coca leaves (the original recipe has the spelling mistake).
Flavourings (7X formula):
80 Oil Orange 40 Oil Cinnamon
120 Oil Lemon 20 Oil Coriander
40 Oil Nutmeg 40 Oil Neroli
1 Qt. Alcohol
There is no indication as to what the numbers preceding the flavour ingredients refer to. However, they may refer to the number of drops.
Directions:
Mix Caffeine Acid and Lime Juice 1Qt.
Boiling water add vanilla and flavourings when cool.
Let stand for 24 hours.
Source: www.sodamuseum.com, www.therisenrealm.com, en.wikipedia.org/wiki/Coca-Cola_formula, "For God, Country and Coca-Cola" by Mark Pendergrast (see the Bibliography).
It is suspected that most, if not all of the lime juice has been replaced by lime oil and that glycerine is now added as a preservative (emulsifier). Also, phosphoric acid is now used instead of citric acid. In the USA at least, some of the sugar has probably been replaced with high fructose corn syrup and artificial sweeteners.
It seems that the cocaine was removed in about 1901 by Asa Candler who commissioned a company to provide decocainized coca leaf. Because of the extraction method used (mulching the leaf in 20% alcohol) there was probably never more than 8.5 mg of cocaine in a 6 oz bottle. J S Pemberton insisted that the drink derived its invigorating properties from fourteen alkaloids [6] that are found in coca leaf and not just cocaine. There is no mention of Kola nuts. The kola nuts were used for their caffeine content and it is supposed that artificially produced caffeine citrate was used from an early date.
The original recipe was for a drink that was not bottled but sold out of "soda fountains" that where situated inside chemist's shops. Therefore, the emulsion stability was not as critical as it is for drinks that are intended to be bottle and have a shelf life of several months.