Mash acidification with Coca Cola

[Drunkula]

I've just looked it up and Coke is the same as 17% phosphoric acid. For acidifying the mash on my last brew I had to use 0.15 ml of 60% lactic acid per litre - I could do the same thing with 0.5 ml / litre of coke. That's nothing - would you taste that in a beer? Probably not. Anyone wanna give it a go?

As a caveat I haven't worked out if the carbonic acid from the fizz would play a factor but I'm sure that would be driven off at mash temperatures.

Yeah, just whiling away the hours until I don't get scowled at if I start to drink.

 

[Ghillie]

Cool idea! Could be a nice way of imparting some colour in a brew as well @Drunkula.

 

[Ghillie]

@Drunkula, when I first read your post I had visions of me pouring a can into the mash. I ran it through Bru'n Water and I'd need just 20.2ml of coca cola for a mash pH of 5.2 on my flagship IPA! 9ml to acidify my sparge water.

I really want to try this!

 

[MyQul]

No that's something Ive never heard of. Go for it and report back.

 

[Drunkula]

Excellent. Ok, coke zero is 14.7% apparently. If I find any more things I'll get back. Rah! Coke mash, for when CRS isn't enough.

 

[braziliain]

I think Coke is essentially a diluted and flavoured phosphoric acid, which is what I use for reducing alkalinity.

 

[Druncan]

Awesome discovery, got loads of OOD coke to dispose of and in a high temp alcal base level, will report back!

 

[Argentum]

Where is the data for Coca-Cola acidity coming from? I would imagine that 17% phosphoric acid is appreciably more acidic than Coca-Cola. I believe that standard Coca-Cola is about 2.53 pH. What pH do you read for 17% Phosphoric Acid?

 

[IainM]

No chance that cola is 17% phosphoric acid. It has a pKa of 2.15, so at 17% that would give a pH of around 1.5. I think someone may have confused 60mg per can with 60g per can. Back of an envelope. you might need closer to 1 part cola to 2 parts liquor.

 

[Argentum]

Transitioning from 2.53 pH for Coca-Cola to 1.5 pH for 17% phosphoric acid indicates that 17% phosphoric acid is about 11 times more acidic than Coca-Cola.

 

[IainM]

OK, lets do this properly. From Coca-Cola: "A glass (250 mL) of Coca-Cola provides 43 mg of phosphorus".

That is 172 mg/litre of phosphorous. Phosphoric acid has mass of 98, of which 31 is phosphorous, so this gives 172*98/31 = 544 mg of H3PO4 per litre. So, coke is a 5.6mM H3PO4 solution, which at pKa of 2.15 gives a pH of 2.43. This is in line with the figure @Argentum gives.

So, rather than 17% phosphoric acid, cola is closer to being a 0.5% solution.

 

[MyQul]

OK, lets do this properly. From Coca-Cola: "A glass (250 mL) of Coca-Cola provides 43 mg of phosphorus".

That is 172 mg/litre of phosphorous. Phosphoric acid has mass of 98, of which 31 is phosphorous, so this gives 172*98/31 = 544 mg of H3PO4 per litre. So, coke is a 5.6mM H3PO4 solution, which at pKa of 2.15 gives a pH of 2.43. This is in line with the figure @Argentum gives.

So, rather than 17% phosphoric acid, cola is closer to being a 0.5% solution.

Completely dont understand what you've just said (apart from the last line) Ian but thanks for the clarifaction, as I'm finding this thread rather intriguing :hat:

 

[strange-steve]

OK, lets do this properly. From Coca-Cola: "A glass (250 mL) of Coca-Cola provides 43 mg of phosphorus".

That is 172 mg/litre of phosphorous. Phosphoric acid has mass of 98, of which 31 is phosphorous, so this gives 172*98/31 = 544 mg of H3PO4 per litre. So, coke is a 5.6mM H3PO4 solution, which at pKa of 2.15 gives a pH of 2.43. This is in line with the figure @Argentum gives.

So, rather than 17% phosphoric acid, cola is closer to being a 0.5% solution.

Since I read the OP I thought it didn't sound right but I'm wasn't smart enough to work it out so thanks for that

 

[IainM]

So, rather than 17% phosphoric acid, cola is closer to being a 0.5% solution.

EDIT: that should be 0.05%

 

[ACBEV]

So, rather than 17% phosphoric acid, cola is closer to being a 0.5% solution

What @IainM is really saying... You need shedloads more coke.

 

[AdeDunn]

Cherry Cola stout anybody?

 

[IainM]

I was was just looking at the water calcs for the TT Landlord clone I'm putting on tonight. If I use 100% cola, then I'd hit the numbers.

 

[-Bezza-]

Anyone else now wondering if they can get a few litres of pop into their next brew? Few extra points with all that sugar too.

 

[Norfolk79]

The question is what drink would you have if you tried to ferment 100% full fat coke?

 

[IainM]

The question is what drink would you have if you tried to ferment 100% full fat coke?

A weak version of this: https://www.thehomebrewforum.co.uk/threads/alco-coke.11583/

I brewed it once. I won't be doing it again.