Too acidic for yeast?

So I'm new to this forum but I've been brewing a while, and recently started really trying to improve the quality of my beers.

After reading about acidifying sparge water I gave it a try by using a relatively small amount of diluted lactic acid. Anyway brew day went smoothly got my 1.060 og IPA brewed and pitched with 2 packs of s-33 dry yeast. A few days went by with absolutely no noticeable fermentation. I added some yeast nutrients. Few more days went by with no fermentation. I then decided to check the ph (using those paper strips) it had appeared to be very acidic (my guess at the time was low 4's)

Today I got my digital ph meter and checked it and got a ph of 4.7 I then added a gallon of water and 3tsp of calcium carbonate and raised it to a ph of 5.1. I then checked the gravity of my beer which to my surprise was at 1.020. Now I know that the gallon of water would have dropped the gravity but I would have assumed by no more that .01. So should I assume it fermented very quickly one night and I missed it or am I missing something?

Also as a general question what is an ideal ph for most yeast and how much is it affected by the ph?

I'd be surprised if you had too low a pH to impact the health of your yeast - at least given the numbers you are reporting. I have brewed a beer using 15% acidualted malt in the grist, which gave a resulting wort with a pH of ~4.4 and it fermented fine.

I'm not sure what the ideal pH is for yeast however. pH is usually discussed in the context of mashing and tannin extraction. And, generally, if you take care of your mash pH, the rest will follow along fine. But if you are interested in reading more about pH in brewing (with a little bit on its effect on yeast), check out http://braukaiser.com/wiki/index.php/How_pH_affects_brewing

In this specific case, I wonder if you just had a slow fermentation - how did you determine that it was not fermenting at first? Did you take any gravity readings? The 1.020 reading indicated that you definitely had some fermentation - you are correct that your OG should have only dropped to 1.050 after the addition of the gallon of water (assuming this was a 5 gallon batch; now a 6 gallon batch). I think you may have jumped the gun a little by messing around with it too much, but hopefully it will finish OK.

Yeast fermentation will naturally reduce the wort pH from its typical low 5 pH range to the mid 4 pH range as the wort becomes beer. There was no need to adjust the pH of the beer upward.

That may be an odd tasting beer. Let us know how it turns out and don't be surprised with beer pH's in the 4 range in the future.

I wasn't taking gravity readings along the way, but I have not seen one bubble come from the blow off tube, and I have been checking. Normally my beers are fermenting (bubbling) rapidly by the next morning. I'll keep you posted. I've been learning some hard lessons lately. Accidentally killed a beer recently by using water that had been softened.

What's your fermentation vessel? A typical issue with buckets is that the lid might not be perfectly sealed, so there's an easy escape path for fermentation gases and your airlock won't bubble.

My guess is that it was fermenting perfectly, but you had a bad bucket seal. This isn't really a problem early in your fermentation anyway, as it's blowing so much CO2 out that very few things have a chance to get inside the beer.

FYI I recently brewed a 1.046 beer with >22% acid malt, and it fermented fine. So I don't think you had an acidity problem.

I typically do primary in a bucket and move to a glass carboy after a week or two. Never had an issue with the seals before, but I will definitely check that out. Still not one bubble seems a bit odd to me even if a seal was bad, the lid was still snapped into place.

So, is the consensus that ph has little effect on the yeast in general (within reason)?

cface said:

I typically do primary in a bucket and move to a glass carboy after a week or two. Never had an issue with the seals before, but I will definitely check that out. Still not one bubble seems a bit odd to me even if a seal was bad, the lid was still snapped into place.

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If you went from 1.060 to 1.020, you were actively fermenting. If you saw no airlock activity, there MUST be a leak somewhere. There's nowhere else for all that CO2 to go!

So, is the consensus that ph has little effect on the yeast in general (within reason)?

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Yep. I think it's unlikely that minor acidification to sparge water would have affected the final product in such a profound way that it caused fermentation to fail.

From braukaiser: http://www.braukaiser.com/wiki/index.php/How_pH_affects_brewing

"For all malt beers a pH range of 4.25 - 4.6 [Narziss, 2005] is generally accepted as optimal while adjunct beers can be as low as 4.0 [Kunze, 2007] and sour beers will be even lower."

A pH of 4.7 post-ferment may, actually, be a bit high.

What was your grain bill? What is your water like? Do you normally brew darker beers? For an IPA, you likely weren't using any roasted grains (which lower pH), and thus you might have had a high mash pH due to highly-alkaline water.

Now that you have a digital pH meter, you should start taking readings of your mash pH and your sparge water, and see where you stand.

Just so everyone knows, the beer did not turn out great, likely due to my changes to it. Lesson learned.

Not sure about ale strains, but I've used saccharomyces bayanus (champagne yeast) in lemonade just because I was bored during a beer conditioning, which is a ph of 2-3, and it worked well. That particular combination tasted fairly disgusting, but it worked.