Saskatoon TechWorks Forum

So, yesterday I revived a project that I have been thinking about for years, and started collecting ingredients for last summer.

Last summer I bought the ingredients necessary to make OpenCola based on the recipe floating around. The process involved mixing a bunch of essential oils with a bit of water (yes, they don't mix) and then adding gum arabic to emulsify the mixture. It didn't work for me. The gum lived up to it's name and I got a lumpy paste about the consistency of partially chewed chewing gum. I got frustrated and gave up.

However, while researching for OpenCola, I had also come up with some recipes that were a bit different. In particular, many of the early recipes used food grade alcohol (Ethanol / "Everclear") to dissolve the oils and allow them to mix into the syrup in the next step. I decided I would use this method with the oils specified in the OpenCola recipe. (Since that's what I have)

The one problem I had, now, is that the syrup recipe calls for 10ml of the "flavoring formula" but since I made it with different components, it would be difficult to determine exactly how much I should be using now. In addition, I have read that modern essential oils are far (as much as 4x) more potent than in the late 1800s, when some of the recipes I've read were written.

In any case, I took a best guess, and I think I guessed VERY high. The cola I ended up making was rather "flowery"

First try:
20ml of 88% Ethanol. (That's what I had. Go to Alberta and buy some Everclear.)
3.5ml orange oil
2.75ml lime oil
1.25ml cassia oil
1.00ml lemon oil
1.00ml nutmeg oil
0.25ml coriander oil
0.25ml neroli oil
0.25ml lavender oil

This made a total volume of 30ml of flavor formula. (This is referred to as 7x in many documents)

Next, I mixed up the syrup. I used:
2.36kg sugar
2.28l water
30ml caramel color
3.5tsp (17g) citric acid
3.65g of caffeine
15ml of the flavor formula

This produced about 3.9 litres of syrup.

The syrup gets mixed 5:1 with water.

So, I took 330ml of syrup, added it to enough cold water to fill a 2 litre bottle, and carbonated.

If you were at the space on May 5th, that's the stuff you tried.

In order to cut down the essential oils in my remaining batch of syrup, I mixed up another batch of syrup minus the flavor formula.

2.36kg sugar
2.28l water
30ml caramel color
25g citric acid (I bumped this up a bit, and changed the measurement to weight)
3.5g caffeine

With these two batches combined, the "flavor" will be effectively halved.

More updates to come...

Also, a few practical notes:

The ratio of sugar to water is pretty high. In other words, it takes quite a bit of agitation for that much tap-cool water to dissolve that much sugar. It might be wise to start with warm (or even some hot) water to help the sugar dissolve more easily.

The anhydrous caffeine powder I got doesn't dissolve very well. I found a few white clumps in the bottom of the first pail of syrup when mixing it with the second batch. I don't have a solution to this, currently. It might be worth reserving some of the water and dissolving the caffeine in another container before adding to the syrup.

Caramel color is really thick, black gunk. The container I used to measure the 30ml had a lot stuck to the sides after pouring it into the syrup. On the first batch, I used the syrup to rinse the measuring device, but by this time the syrup is also a fairly thick mixture. For the second batch, I reserved some of the water and used that to rinse the measuring cup.

Oh, and don't taste the flavoring formula. I know it's tempting, but trust me, just don't. Even the syrup doesn't taste pleasant.

And, a huge disclaimer: Caffeine is dangerous. Don't be tempted to "wing it." Use an accurate scale and double-check your calculations. My recipe above comes out to about 156mg / litre of finished cola, or about 55mg per "can". (about the same as Mountain Dew) Still, don't trust my calculations... do your own.

I worked a summer at a camp. They had concentrated flavouring for the recirculated juices. Bet a kid $2 he couldn't take a shot of the concentrated lime ricky. He gagged for around 5 minutes. Totally worth it.

This is the recipe we used at the open house in November 2016. Actually, we mixed up 3 times the recipe of 7x and used the rest to make cola soap.

OpenCola Mk III

Mix up some 7x:
1.75ml Orange Oil
1.375ml Lime oil
0.625ml Cassia Oil
0.5ml Lemon Oil
0.5ml Nutmeg Oil
0.125ml Coriander Oil
0.125ml neroli Oil
Plus a little bit of everclear. (10ml?)

Mix up the syrup.
2.36kg of sugar
2.28l of water, but reserve some for later. Try hot water to better dissolve the sugar.
30ml of caramel color. Use some of the reserved water to rinse the container.
25g of citric acid
3.65g of caffeine. Try mixing this in some of the reserved water.
Then add the 7x.

This should make about 3.9l of syrup.

Mix 5:1 with cold water. Carbonate.
(or remove 330ml of club soda from a 2l bottle, replace with syrup. mix.)

This recipe should make 23.4l of cola.


Corny Keg is 18.9l.
Use 15.75l of water +
3.15l of syrup.

Enough syrup left to flavour 2 x 2l bottles of club soda!