PH to Concentration of Citric Acid

[Reinhardt]

I am working on making Meads (Honey wine) and after speaking to a master Vinter he advised I lower the pH of my starting water & honey mixture to 3.5 for various reasons. I'm interested in experimenting to see if this gives a noticeable taste difference to the mead.

I know honey is Basic but not horribly so (I think) so rather than sit with some litmus paper for lord knows how long to make things exact I figured I'd just add the mathematical amount required to get water to that level since the experiment is more about what is observable.

That said How much Citric acid (Dry white crystalline powder) do I add to make 1 gallon of water 3.5 pH? To make 5 gallons I would just multiply that number by 5, yes?

Thank you.

 

[Borek]

Less than 0.1 g per liter. However, this information is useless for your application, as you don't have pure water, so you can expect some buffering effects.

Are you sure honey is basic? I always thought it is slightly acidic.

 

[MrSid]

Borek is correct that your honey wort will be a buffered solution with unknown characteristics towards the acid. The honey in water may already be acid to Litmus; when you have added some of the salts used as nutrients (typically ammonium phosphates, and potassium phosphates) you may see this go more towards neutral.

If you only have litmus to test with, you could be able to do a practical test of making up the honey, the nutrient salts in your tap water at the appropriate concentrations but only a liter or less. You will have to be able to weigh the components at a 1% accuracy. Check the pH with litmus after getting everything dissolved.

Take and make a similar solution of citric acid in neutral (to litmus) water that will give you a way to back calculate your citric acid (for any added volume ) by weight.

Then take an aliquot of the honey wort and use the citric acid solution to do your titration with a eyedroper. You can also set up a set up test tubes and vary the amounts of citric acid to the aliquots of wort to see which stay strongly acidic to litmus. Make larger test solutions from the wort and citric acid that seem to agree to your best guesses from Litmus as to the acidic solutions. Then use taste to test for which acidified wort you are likely to to want to ferment.

Use ratios to set up the calculations to make your larger batch (make sure to convert the volume of citric acid to the weight of contained citric acid in that volume).

If possible you should also invest in some test strips that will change color nearer to the pH transition desired. If you use indicators or a pH pen to determine pH DO NOT TASTE TEST those aliquots! pH pens uses Calomel inside the glass electrode and could give you a dose of Hg.