Projects:Making cola

I (Sjors) recently saw this video by LabCoatz reverse engineering the Coca-Cola recipe using (among other techniques) a mass spectrometer: https://www.youtube.com/watch?v=TDkH3EbWTYc

Now I'm a bit of a Coca-Cola addict, so I'm intrigued and want to reproduce it.

Perhaps once we've done this we can also make other kinds of cola, like Toyen Cola, which has its recipe on the back. We could even do a taste test!

Overview

LabCoatz calls the end product of their recipe LabCola. One liter of LabCola is built off of four components:

• around 100g sugar
• 1mL of flavor solution A
• 10 mL of flavor solution B
• around 1 liter of carbonated water

Flavor solution A is made by adding the following components together (~100mL), then taking 20 mL from that and diluting to 1L using 95% ethanol:

• 45.8mL lemon oil (NOW)
• 36.5mL lime oil (NOW)
• 8mL tea tree oil (NOW, from Australian tea tree, Melaleuca Alternifolia)
• 4.5mL cassia cinnamon oil (NOW)
• 2.7mL nutmeg oil (aura cacia)
• 1.2mL orange oil (unknown brand, regular sweet orange)
• 0.7mL coriander seed oil (Edens Garden, coriandrum sativum)
• 0.6mL fenchol (any version of alpha-fenchol should work)

Flavor solution B is made by adding the following components together (~400mL), then diluting to 1L using water:

• 185mL caramel color (Durkee)
• 150 grams food-grade vegetable glycerin (Equate)
• 43mL 85% phosphoric acid (Duda Energy)
• 10 grams wine tannin (North Mountain)
• 9.65 grams caffeine
• 10mL 5% vinegar (any white vinegar?)
• 10mL vanilla extract (or a solution containing 0.95 grams per liter of vanillin)

It's important to note that this is not the Coca-Cola recipe, which uses coca leaf extract. It is supposed to be quite close, though.

Tools

• Mass scale
  • Max measurement is 150g, most precise measurement is 9.65g
  • source: Michiel has two: <200gr with precision 0.01g & <600gr with precision 0.1gr.
• micropipette + tips
  • ideally an adjustable micropipette, but these are quite expensive (€100+)
  • fixed 100µL micropipette is cheaper, €25 https://www.merkala.nl/minipet-microliterpipet.html
  • could also get a few doseerspuit at Kruidvat, €2, precision should be somewhere between 0.1mL and 0.5mL
  • setje graduated pipettes €15,85 https://www.amazon.nl/pipetten-Graduated-Reinigingsborstel-Roerstaaf-Laboratorium/dp/B07V3VC7YZ
• 50 mL graduated cilinder
  • €14,74 https://www.labshop.nl/maatcilinder-hoog-model-klasse-a-bruine-schaalverdeling/?attribute_pa_volume=10-ml
• some storage bottles (mainly 1L)
  • I'll produce 100 mL of pre-solution A, then dilute that into 1L of solution A and store the rest of the 80mL separately. Solution B is 1L at a time, so I'll need 3 storage bottles.
  • I'm considering to produce only 10 mL of pre-solution A then dilute that into 100mL of solution A. Since the solution offgasses it requires very little air in the bottle, so a 100mL bottle would be a good idea.
  • https://www.labshop.nl/labfles-glas-blank-gl45-blauw-simax/
  • €12,40 * 3 = €37,20
• heat-resistant glassware for preparing the syrup (1L)
  • €9,23 https://www.labshop.nl/bekerglas-laag-model/
  • or €7,45 https://labstuff.nl/contents/nl/p135.html
  • Ø 105mm, so watch glass ~€3 https://labstuff.nl/contents/nl/p253.html
• magnetic stirrer for mixing
  • source: Michiel has one
• 100mL volumetric flask to make the dilution steps easier
  • for pre-solution A
  • €22,63 https://www.labshop.nl/maatkolf/?attribute_pa_volume=100-ml-ns12-21-klasse-a
  • €11,15 https://labstuff.nl/contents/nl/p4695.html
• water carbonator / sodastream
  • Sjors has this at home
• gloves / safety glasses
  • gloves €4,17
  • Sjors already has safety glasses

If we don't need to buy the mass scale nor magnetic stirrer, tools come out to approximately €125.

Ingedients

Ingredient	Source link	Quantity	Quantity necessary	Order amount	Price per piece	Price total	Makes L solution12	Makes L cola	Price per L cola
Overall
Sugar	Makro (Van Gils kristalsuiker)	1kg	Around 100g	1	€0,75	€0,75		10L	7,5 cents
Carbonated water	Self-made		Around 1L
Flavor solution A
Food-grade 95% alcohol	Makro (Chauffe coeur)	1L	1L	1	€32,42	€32,42	1L	1 kL	3.24 cents
NOW Lemon oil	iHerb (alternative Bodystore)	30mL	45.8mL	2	€7,01	€14,02	6,55L	6,55 kL	0,23 cents
NOW Lime oil	iHerb (alternative Bodystore)	30mL	36.5mL	2	€12,47	€24,94	8,22L	8,22 kL	0,19 cents
NOW Tea tree oil	iHerb (alternative Bodystore)	30mL	8mL	1	€9,42	€9,42	18,75L	18,75 kL	0,05 cents
NOW Cassia cinnamon oil	iHerb (alternative Bodystore)	30mL	4,5mL	1	€8,04	€8,04	33,33L	33,33 kL	0,03 cents
Aura Cacia Nutmeg oil	Amazon.com out of stock (alternatives different brands iHerb, Berivita no GC/MS available)Ordered from VeniVida.com, different brand but with very similar GC/MS measurements, so should taste equally.	10mL	2.7mL	1	$5,99	€5,19	18,51L	18,51 kL	0,03 cents
NOW Orange oil	iHerb (alternative Bodystore)	30mL	1.2mL	1	€5,53	€5,53	125L	125 kL	<0,01 cents
Edens Garden Coriander seed oil	Edens Garden (alternative Amazon.com, different brand bol.com)	5mL	0.7mL	1	$14,95	€13,33	35,71L	35,71 kL	0,06 cents
Alpha-Fenchol	Amazon.com (alternative Pellwall (UK), eBay, pevgrow (€27,90 incl shipping?), terpenes (£32 incl shipping)	30mL	0.6mL	1	$12,99	€11,25	42L	42 kL	0,02 cents
Total flavor solution A						~ €120	1L	1kL	€0,03 when produced at scale €0,12 for first liter
Flavor solution B
Durkee caramel color	Amazon.com (alternative Pantryful)	32 oz. (946 mL)	185mL	1	$17,95	€15,54	5,11L	511L	2,3 cents
Food-grade vegetable glycerin	Amazon.nl (alternative Labshop, werkenmetmerken.nl €9 for 1L)	250mL	150g (~150mL?)	1	€5,99	€5,99	1,67L	167L	4 cents
85% Phosphoric acid	Labshop	1L	43mL	1	€20,27	€20,27	23,26L	2326L	0,8 cents
North Mountain Wine tannin	Amazon.com (alternative different brand Brouwland)	56g	10g	1	$20,66	€17,89	2L	200L	3 cents
Caffeine powder	VoordeelkruidenIf we want more: Woele alternative: Laboratiumdiscounter	50g	9,65g	1	€2,60	€2,60	5,18L	518L	0,5 cents
5% vinegar	Makro (Burg natuurazijn 4%, dus gebruik 25% meer?)	1L	10mL	1	€1,01	€1,01	100L	10kL	<0,01 cents
Vanilla extract	Amazon.nl (alternative Laboratoriumdiscounter but expensive shipping, alternative Makro.nl but don't know vanillin strength)	100g	1g (dissolve in 100 mL water, take 0.95mL)	1	€9,80	€9,80	10kL	1ML	<0,01 cents
Total flavor solution B						~ €70	2L	200 L	€0,11 when produced at scale €0,35 for first liter

(1) The essential oils in solution A, quantities as under "Quantity necessary", together make 100mL of pre-solution. "Flavor solution A" then consists of 20 mL of pre-solution, diluted to 1L using alcohol. So for each mL of essential oil in the pre-solution, a fifth (0.2 mL) goes into a liter of the actual solution. So quantity times order amount is the amount of ingredients we have, divided by quantity necessary is the amount of 100mL pre-solution we can make with the order. We can make 5L of solution with that, so the formula is: (quantity * order amount * 5) / (quantity necessary). Since 1mL of solution A goes into a L of cola, 1L solution makes 1000L cola.

(2) For solution B, the ingredients together make about 400mL of pre-solution. "Flavor solution B" then consists of those 400 mL, diluted to 1L using water. So the "quantity necessary" goes directly into 1L of "Flavor solution B". Since order amount is 1 for all of these, the formula is: quantity / (quantity necessary). Since 10mL of solution B goes into a L of cola, 1L solution makes 100L cola.

Expiry

After the first batch I'll have a liter of solution A, which is almost fully alcohol, so I expect it not to expire at all. This bottle is good for a thousand liters of cola, which is probably enough for a lifetime.

I'll also have 80 mL of pre-solution A, which I'll store separately. I also expect it not to expire, but to be sure, I could add alcohol to this as well, and label the bottle as such so I know exactly how much diluted pre-solution contains 20 mL of the original pre-solution.

As for solution B, I'm not sure but I expect that will expire faster. The original ingredients probably don't expire if closed well? If I make 1L that's enough for 100 L of cola, which probably lasts a few months unless it's really popular.

Knowing nothing at all about food safety I asked Claude for secondary advice. ("This is a cola syrup, isn't it?") They said the solution A mixture would remain safe indefinitely, but chemical degradation would affect aroma over the years; they advise to reduce air in the bottle, reduce repeated opening (freshening of the oxygen), reduce heat and reduce light exposure. With that, realistically expiry could be pushed well beyond 5 years. For solution B, they said microbial stability is also very good due to the phosphoric acid (1.0-1.5 pH). Again, chemical degradation is the limiting factor. Sealed, room temperature and out of light, Claude expects 12-18 months for peak flavor, and "probably safe well beyond that". It says the main thing to watch out for is sediment from the tannin, and flavor decreasing. Neither makes it unsafe. Commercial cola syrups like this one carry 6-12 month best-by dates, and it says our threshold for "still good" may be more forgiving.

As for the original ingredient bottles, I should check if they are labeled with best-before dates and label them with the date I first opened them. Claude says the essential oils are most perishable; they will degrade in 6-12 months. For vanilla extract it's often commercially dated 2-4 years. All other things are either really easily purchaseable or very long-lived (5+ years).

Conclusion:

• Keep the bottles at room temperature (or colder), in the dark, and with little air headspace in the bottle.
• For the solution A bottles, I'll mark them with their production date and "expected best before date" of 5 years.
• For the solution B bottles, I'll mark them with their production date and "expected best before date" of 12 months.
• For the original ingredient bottles, I'll store them the same way. I could consider making more pre-solution with alcohol for preservation.

Financial overview

This is a hobby project, so it's OK if it costs money and isn't cost-effective. However, I wanted to get an overview for myself.

Initial, one-time investment into tools is €125. The initial investments into ingredients for the first run is ~€200, and shipping is €100. That means the first batch costs €425 and we can produce around 200 liters of cola from this. If it tastes great and is popular and people want to drink it instead of Coca-Cola, I could sell it at a cost price of €2,13 per liter.

If we actually (expect to) make more than 200 liters, then for the next 200 liters I'd only need to purchase additional wine tannin. So for the first batch of 400 liters, at a cost of ~€450, it'd already be €0,88 per liter. So that's what the price becomes if it turns out to be quite popular. Eventually, if it's really popular it would cost €0,14 for the flavor solutions, plus some sugar and carbonated water.

All orders done for the first batch:

• Edens Garden $14,95 (€13,33)
  • Edens Garden Coriander Seed essential oil
• Amazon.com $86,06 (€76,55) $66,17 (€59,67)
  • Durkee caramel color
  • Alpha fenchol
  • Aura Cacia nutmeg oil (refunded, not in stock)
  • North Mountain wine tannin
• VineVida.com $13.73 (€11,36)
  • VineVida nutmeg oil
• iHerb €61,95
  • NOW Lemon oil
  • NOW Lime oil
  • NOW Tea tree oil
  • NOW Cassia cinnamon oil
  • NOW Orange oil
• Amazon.nl €31,64
  • Graduated pipettes
  • Vanillin powder (foodgrade)
  • Glycerin 99.5% (foodgrade)
• Labstuff.nl €35,57
  • Glassware (beaker, watch glass, volumetric flask)
• Labshop.nl €81,30
  • Graduated cylinder
  • Storage bottles
  • 85% Phosphoric acid
• Voordeelkruiden.nl €7,55
  • Caffeine powder
• Makro €38,35
  • Sugar
  • Vinegar
  • Pure alcohol (food-grade)
  • Gloves
• Shipping MyUS USA/FL -> Netherlands $110 (€100,60)
  • ~$40 base charge
  • $30 "dangerous goods surcharge" (unexpected, since the items were below the "limited quantity threshold", but the company refused to waive)
  • $30 prepaid customs fees (unexpected, since the total shipment value should be below threshold, but I wanted to prevent any customs issues)
  • $3,50 liability coverage
  • mark "for personal use" and include a proforma invoice

Total paid: €441,32

To purchase:

• two tiny 5mL bottles for dilutions to make pipetting easier - https://www.glazen-en-potten.nl/helder-glazen-flessen-5ml-met-wit-schroefsluiting-st-4937.html
• one 100mL bottle for the vanillin dilution

The process

This is, at least initially, exactly from this video: https://www.youtube.com/watch?v=TDkH3EbWTYc specifically the recipe in the description at the time of writing (version 111C)

Equipment preparation & training

For every step, even those later in this chapter:

• Wear gloves (and potentially, safety glasses)
• Measure accurately
• Don't taste any of the unmixed/undiluted ingredients

I've prepared by doing equipment training, first. I have a graduated pipette with lines every 0.01mL. I'm quite comfortable to give a 0.01mL margin for every measurement I do with it, after playing around with it a bit. The smallest oils (0.07mL coriander and 0.06mL fenchol) I will make dilutions for; the others, I will pipette directly. Between every pipette usage, I'll rinse three times with 95% alcohol.

• Experiment with taking and dispensing ~0.1mL oil with a precision of 0.01mL.
• Experiment with measuring and dispensing exactly 9.65 grams of powder. This is necessary for caffeine.
• Experiment with mixing/diluting in bottles and the volumetric flask.

Make 7X concentrate and syrup 1

What we're making:

• ~10mL of 7X concentrate - the raw oil mixture
• ~500mL of syrup 1 - the 7X concentrate diluted in ethanol, used at 1mL per liter of final cola.

Note that the original video recipe makes 100mL of concentrate and then uses 20mL of that for 1L of syrup - the total mixture is the same, but there's a lot more potential waste.

Preparation:

• Re-read safety instructions above
• Prepare a bit of ethanol (a.k.a. food-grade 95% alcohol) and a waste container for pipette rinsing (~15mL)
• Warm up/melt the fenchol in hot water until fully liquid before beginning
• Prepare a fenchol solution: 0.5mL fenchol + 4.5mL ethanol, label with "1:10 fenchol dilution", production date and the best before date of the fenchol bottle
• Prepare a coriander solution: 0.5mL coriander oil + 4.5mL ethanol, label with "1:10 coriander oil dilution", production date and the best before date of the coriander bottle

Now, we make the 7X concentrate. Take a clean 1L glass bottle. Label the bottle "Syrup 1 - 2% oil in ethanol - use 1mL per liter of cola", and add the production date and the earliest best before date of any of the ingredients. Add the oils in the following order, rinsing the pipette twice with ethanol between each ingredient (begin with 0.5mL pipette, switch to a larger one as convenient while keeping exact measurements):

• 0.6mL liquid fenchol from the 1:10 dilution
• 0.7mL coriander oil from the 1:10 dilution
• 0.12mL orange oil (regular sweet orange)
• 0.27mL nutmeg oil
• 0.45mL cassia cinnamon oil
• 0.8mL tea tree oil (from Australian tea tree, Melaleuca Alternifolia)
• 3.65mL lime oil
• 4.58mL lemon oil

The glass bottle now contains slightly more than 10mL of pre-syrup, since the fenchol and coriander oils were diluted.

Now, very carefully fill to 500mL with the ethanol (food-grade 95% alcohol). Absolutely do not overfill, so if necessary do the last part with a pipette. The 500mL mark on a graduated bottle is approximate, but this only affects intensity of the final flavour, not its character.

Close the bottle tightly and invert several times to mix.

The video lets the concentrate age for a day or two before diluting in ethanol, but I won't, because (1) I'm concerned it'll offgas significantly into the 1L bottle, and (2) Claude says ageing is fine to do after adding ethanol instead of before (perhaps even better). TODO: watch Art of Drink video on this.

If it turns out that 1mL is too much or not sufficient for the perfect taste, add a note to the label to use more/less than 1mL as appropriate.

Make vanillin solution

What we're making:

• 100mL of vanillin solution at 0.95g/L (according to the original recipe), used in syrup 2

Steps:

• Weigh 0.10g vanillin powder (or slightly less) onto a paper funnel and tip into a clean 100mL volumetric flask
• Add water to roughly half full and swirl to dissolve
• Fill to the 100mL mark with water
• Add the stopper, invert several times to mix
• Label "Vanillin solution - 1.00g/L", add production date and best-before date

The recipe calls for 0.95g/L but we can't measure that accurately unless we switch to a 1L solution.

If the vanillin doesn't readily dissolve, try with warm water, or otherwise try with a few drops of ethanol.

Make syrup 2

What we're making:

• 100mL of water-based syrup, used at 10mL per liter of final cola.

Preparation:

• Re-read safety instructions above
• Gloves and safety glasses are especially important for the phosphoric acid step
• Have the vanillin solution ready
• Prepare a paper funnel for the powders

Into a clean 100mL volumetric flask, add ingredients in this order, swirling to fully incorporate each before adding the next:

• 20mL hot water
• 1.25mL vinegar (4% natural vinegar, was 1mL 5% vinegar)
• 0.97g caffeine - weigh onto paper funnel, tap carefully into flask
• 1g wine tannins - weigh into paper funnel, tap carefully into flask - swirl until both powders are fully dissolved
• (put on a scale and tare the scale for the next step)
• 15g glycerin - pipette directly into flask until scale reads 15g
• 4.3mL 85% phosphoric acid - add slowly by pipette
• 1mL vanillin solution from before
• 18.5mL Durkee caramel color

Once everything is dissolved, fill to the 100mL mark with water. Put the stop in and invert several times to mix.

Either keep this in the flask, or move it to a 1L bottle labeled "Syrup 2 - water based - use 10mL per liter of cola", add the production date and earliest best before date of the ingredients.

This syrup doesn't need to sit after making it.

Make the first solution

To prepare, make 1L of carbonated water and put it in the fridge so it's cold.

• Take a 1L beaker that's heat-proof.
• Add 104g sugar, and just enough water to dissolve the sugar (50-100mL?).
• Add 10mL of the water-based solution (syrup 2).
• Add 1mL of the alcohol-based solution (syrup 1).
• Swirl to combine.
• Mix and microwave (or otherwise heat) the mixture until nearly boiling, while covered with the watch glass.
• Allow to cool completely to room temperature.
• Once fully cooled, transfer to a 1L graduated bottle and dilute to a volume of 1L with cold carbonated water.

You can drink this directly, but for the most accurate flavor it's best to let it rest for a day or so in the fridge.

If the flavor is too mild, add more syrup 1; if too strong, add less.