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View Full Version : pH .vs. TA (titratable acids) conlflict



iNeedMead
03-04-2011, 05:04 PM
This is my first Mead, using a recipe (before finding GotMead!) which had me use lime, lemon and orange juice up front.
15# honey
4G H20 (~5 Gal must)
1/4 C lime
1/4C lemon
1/4C Orange juice
1 cup strong Early Gray tea.
Lalvin EC-1118 yeast

So obviously my pH is too low and the yeast struggled but came through. OG was 1.10x and SG looks like .998.
I added 2tsp potassium bitartrate (Cream of Tartar) at day 5 with my feedings and 1tsp at day 6 an another 1tsp at day 7. pH still below 4.0 using beer test strip (range is 4-7). Ran out of COT and gave up.

So I went to my LHS and sought advice - he sold me a tritatable acid test kit but could not explain how to use it -- kept insisting I ignore the pH even though that was why I was there.

So here is my dilema. My acid content is .40 or 4g/L The 'desireable' acid for white grape wine is .75% and fruit wine is .60% I don't know what mead should be. Assuming I am looking for .60 or more this suggests I need to INCREASE acidity which is confusing since that would further lower my pH which is counter intuitive to the whole point of this pursuit.

What am I missing here?

Once the numbers were stabilized I am planning to save 1G as traditional Mead and transfer 4G to secondary with Oregon Raspberry puree, but have no clue about TA .vs. pH at this point.
Help, please????

wayneb
03-04-2011, 05:51 PM
This is my first Mead, using a recipe (before finding GotMead!) which had me use lime, lemon and orange juice up front.
15# honey
4G H20 (~5 Gal must)
1/4 C lime
1/4C lemon
1/4C Orange juice
1 cup strong Early Gray tea.
Lalvin EC-1118 yeast

So obviously my pH is too low and the yeast struggled but came through. OG was 1.10x and SG looks like .998.
I added 2tsp potassium bitartrate (Cream of Tartar) at day 5 with my feedings and 1tsp at day 6 an another 1tsp at day 7. pH still below 4.0 using beer test strip (range is 4-7). Ran out of COT and gave up.

So I went to my LHS and sought advice - he sold me a tritatable acid test kit but could not explain how to use it -- kept insisting I ignore the pH even though that was why I was there.

So here is my dilema. My acid content is .40 or 4g/L The 'desireable' acid for white grape wine is .75% and fruit wine is .60% I don't know what mead should be. Assuming I am looking for .60 or more this suggests I need to INCREASE acidity which is confusing since that would further lower my pH which is counter intuitive to the whole point of this pursuit.

What am I missing here?

Once the numbers were stabilized I am planning to save 1G as traditional Mead and transfer 4G to secondary with Oregon Raspberry puree, but have no clue about TA .vs. pH at this point.
Help, please????

My suggestion would be to return the TA kit while it is still unused (unless you used it to find your 4 g/l number), and if your LHBS proprietor wants to know why, point him to this forum and ask him to search on the terms "gluconic acid" and "gluconolactone." He will learn a lot.

In summary, though, testing TA with a honey based must, even with other fruit adjuncts, is prone to significant error, because of the gluconolactone-gluconic acid equilibrium reaction that occurs in every mead must. Essentially, while you would be busily trying to look for indicator color change during your titration, the equilibrium reaction will be just as busily "restoring" the natural acid balance of the must, and so your results will be severely skewed. The only quantitative test that makes any sense in a honey based must is one for pH.

In the future (and perhaps even in this batch, if the pH is below about 3.4 - you really need to get either an electronic pH meter or pH strips that measure down to about 3.2), try using potassium carbonate or potassium bicarbonate rather than the bitartrate to adjust pH up. Additions of potassium bitartrate won't actually affect the pH of your must to any great extent, and it will eventually form a supersaturated solution which could cause bitartrate crystals to precipitate out of the finished mead when it is in the bottle. Did the LHBS guy tell you to use bitartrate? If so, then I might suggest actually finding a different homebrew shop to deal with.

iNeedMead
03-04-2011, 07:09 PM
Thank you. The kit is now used (I followed directions like a good little sheep). I had come to the same conclusion re: finding an alternate LHBS before I had even left the shop - too bad he is the ONLY game in town. I am a NewBee, but I felt he was even more ignorant and quite argumentative. I did go there in search of KOH and came home with K2CO3.

So, to make sure I understand. Just add K2CO3 (1/2 tsp at a time?) until my pH is at target and completely ignore the TA, correct (exact opposite of LHBS advice)?

Fyi, I did find the following article to back up what you said:
http://www.washingtonwinemaker.com/blog/2009/02/23/difficult-acidity-problems/
I could swear I had found a similar thread in GotMead but no longer can.

Unfortunately I found several others that include mead and wine in the titration excersises with no differentiation.

wayneb
03-04-2011, 07:27 PM
So, to make sure I understand. Just add K2CO3 (1/2 tsp at a time?) until my pH is at target and completely ignore the TA, correct (exact opposite of LHBS advice)?



Yup - that is the recommended approach.

And for future reference, Dan McFeeley is our own resident expert on the acid-lactone reaction in mead musts. His most recent post on the subject is here: http://www.gotmead.com/forum/showpost.php?p=159406&postcount=5 but if you'd like to read more, do an advanced search on the terms I provided earlier with McFeeley as the author, and you'll find lots of his posts discussing the reaction and its effect on TA in mead musts.

Chevette Girl
03-04-2011, 07:50 PM
<sigh> and for those of us without paypal accounts with which to procure patron status, here's a good one... http://www.gotmead.com/forum/showthread.php?t=17001, I looked up "gluconolactone".

wildoates
03-04-2011, 08:04 PM
Don't feel bad about taking the less than sterling advice from your LHBS guy--first, they're kind of like doctors to noobs, holding the key to the most arcane brewing knowledge, and we who go to them for advice have no way of knowing whether the advice is good or bad. Next, while the basics of brewing are rather simple on their face, there can be a lot of variables to trip you up even when you are following good advice. Also, most brew shop guys brew beer or wine, not mead. They just don't know the differences. Finally, you made your way here, which is the best thing you could do. There's very little than can happen that the mentors haven't already seen and know a remedy for...I don't think offhand I've ever seen the advice "you totally ruined it, dump it down the sink." They do know mead, and if it can be saved and made awesome (or at least drinkable ;D), they'll know how to do it!

iNeedMead
03-04-2011, 08:23 PM
Thank you all for the support. I'm learning more brewing mead, beer and hydrogen than I ever did in chemistry classes! 3 Tsp Potassium Carbonate did the trick. I did a TA for grins (what else can I do with the kit -- I aint driving 90 minutes to go back there!) and it showed .30 -- so at least it indicated the correct direction (less acid in must now)

I'll search for a related thread, but is there a recommended affordable pH Meter? I figure the imported ones would be less accurate or consistent than strips.

wildoates
03-04-2011, 08:36 PM
Oh, and I just noticed that you're at least semi-local to me!

mmclean
03-04-2011, 09:14 PM
Thank you all for the support. I'm learning more brewing mead, beer and hydrogen than I ever did in chemistry classes!

Your brewing hydrogen? Do tell.

wayneb
03-05-2011, 01:33 PM
<sigh> and for those of us without paypal accounts with which to procure patron status, here's a good one... http://www.gotmead.com/forum/showthread.php?t=17001, I looked up "gluconolactone".

Sorry, guys! I thought I grabbed one that wasn't in the Patrons section... really I did. :-\

Medsen Fey
03-08-2011, 06:40 PM
So obviously my pH is too low and the yeast struggled but came through. OG was 1.10x and SG looks like .998.


Whatever the pH issues were, at this point, the EC-1118 has successfully fermented the mead. Once fermentation is complete, you don't really need to worry about adjusting the pH (unless it is over 4.0 - and maybe not even then). We adjust the pH to allow the yeast to function, and once they are done, knowing the pH can be helpful for getting the dose of sulfites to the right level, but you no longer need to adjust it.

Adjustments made after fermentation is finished should be done to get the right flavor balance, and that can involve sweetening, or acid adjustments. For this you can toss the pH strips aside and just use your taste buds - you can trust them to know when it tastes best.