Open-source cola is anycola soft drink produced according to a published and shareablerecipe. Unlike the secretiveCoca-Cola formula, the recipes are openly published and their re-use is encouraged.[1][2] The texts ofOpenCola and Cube-Cola recipes are published under theGNU General Public License (GPL).[2][3][4]
The colas are produced as a flavour concentrate or syrup that is then mixed with bulk ingredients to produce the drink. Completed flavour concentrates are sold by some of the open cola producers.[5] The bulk ingredients include those such as sweeteners (sugar orartificial),caffeine and the source of acidity,phosphoric orcitric acid as these are added later, after the flavour blending stage, sugar and caffeine levels per batch can be tailored to a market's particular taste.
Coca-Cola's own flavouring syrup is known in-house as "Merchandise 7X", which is cross-referenced in the open recipes.[2]
A typical recipe is based on eightessential oils, listed here in approximate order of decreasing volume:[2]
These are based on the "Pemberton formula."[6] Although claimed as the Coca-Cola recipe, this has been denied byThe Coca-Cola Company.[7] This recipe is also similar to the Merory and Beal recipes. One ingredient that is missing from these recipes is the eponymouskola nut,[8] although this did appear inReed's recipe.
The use of lavender oil is considered something of a personal taste.[according to whom?] Neroli is frequently omitted altogether, owing to its high cost and relatively small contribution to the overall flavour.[4] Neroli alone may represent a third of the concentrate ingredients' cost.[9]
As well as the basic list of flavouring ingredients, there are other ingredients such as food gradegum arabic and a considerable degree of "art" in its manufacture. The precise quality and sourcing of ingredients makes an appreciable difference, particularly in the process ofemulsifying the concentrate.[4]
Small quantities of alcohol may be used to facilitate this process; as an open recipe, this is under the control of the manufacturer who may avoid such ingredients ifprohibition,halal, or similar rules would require it.
Examples includeOpenCola, produced as a promotion by theOpencola software company, and Cube-Cola, an open cola produced by theCube Microplex cinema inBristol.[7]
Tøyen-Cola fromNorway is one of the Cube-Cola offsprings.[10]
