post-fermentation pH too high (second failed berliner attempt)

[napx]

Hey all. I've been experimenting with kettle souring because I love sour beers but can't (yet) justify a second set of equipment. However, I've yet to knock even the simplest sour (a berliner) out of the park. The first batch ended up the victim of a stuck fermentation. It's rare that I dump a batch, but I dumped that one. Sadness.

This time around I smartened up and made a proper starter with a kolsch yeast, as I figured it was more likely to survive the harsher pH. The pH coming out of 24 hours of 95-100F souring with goodbelly shots was 3.4. The kolsch yeast went in, and started fermenting like a champ. I left for a prolonged work trip. Came back, prepared to bottle, and it looks like fermentation has completed (super low FG at 1.002) but my pH is 4.0. Needless to say, it doesn't taste very sour.

So 2 questions:

(1) is there any way to save this batch? And by save, I mean, ratchet up the sour (lactic acid? no?). Honestly it's drinkable, just not at all what I was looking for, and

(2) what did I do wrong so I can avoid it next time? Any thoughts? Is a kolsch yeast not the right fit? Did I let it sit in the fermenter too long? Was my temp profile off (70F)? I'm thinking it may have been the temp, but I've heard of others having no problem fermenting at that temperature. Maybe I misread.

Thanks in advance for any tips!

 

[Zigs6]

Well, You could have soured for longer shooting for a PH of around 3.2. You should achieve that after 36 hours or so. You could try putting a little lactic in it to taste. It will definitely make it sour, it will just lack the complexity that the lacto sour has. I've used good belly before and it worked really well for me pitching 2 big jugs per 10 gallons and letting it ride for 36 hours in the 90's. That's interesting how the kolsch yeast brought up the PH though. I used US-05 and mine stayed around the same post fermentation.

 

[crane]

It seems unlikely that it would rise that much after fermentation. How are you measuring PH? Strips or a meter? If meter, are you calibrating the meter before each use?

 

[napx]

I would have soured it more but it tasted perfect going into primary and I didn't expect the pH to rise so much after fermentation (weird?). Also, the first batch I did I let it go to 3.2 and then ended up with a stuck fermentation which I (perhaps incorrectly) blamed on too much acidity in the wort.

As for measuring, yes, I've been using a meter. And yes, recalibrating before use.

 

[napx]

I've heard some say that adjusting with lactic acid isn't a bad way to go. Another route might be racking it over some fruit to add more sourness / complexity (sour cherries or rhubarb maybe). Any opinions?

 

[TheMadKing]

I don't understand what would cause pH to rise during fermentation unless you have a measurement error somewhere. I did the exact same thing you did, and ended up with a great berliner-weisse. I wouldn't sour it much below 3.4 because then you start interfering with the yeast health.

Also, just FYI, a berliner-weisse is not a super sour beer, it should be a gentle tartness. You can increase the sourness by adding tart syrups (raspberry is traditional), or straight lactic acid works too. Something like 15mL should get you in the ballpark of where you want to be.

I personally love a cranberry syrup in mine, Hibiscus or huckleberry are also great.

 

[MrFancyPlants]

Just throwing another idea out there but you could pitch some lacto planterum (good belly) in there now and it would likely make it more sour as long as there isn't too much IBU to restrain it's growth. It's might make it too tart though.

 

[napx]

So I ended up adding just a bit of lactic acid, bringing the pH down to around 3.7. Still not quite as tart as I'd have liked but I was nervous about any more of it contributing to off-flavors. It still has a nice taste to it, just lacking that edge / tang that I usually associate with a nice crisp Berliner. Next time around I'll let the goodbelly work a bit longer, but I'm still at a loss as to why the pH rose back up so much post-fermentation. And seriously, I calibrated and double checked my numbers, as well as tasted before and after... *shrug*

I'll see how it tastes after it's been in bottles for a couple weeks and then try another batch (maybe with some fruit in the mix this time). Practice makes perfect.

 

[Morrey]

What kind or type of ph meter are you using?

Raising ph in your final beer after souring has me stumped. I have made many batches of Gose beers and not a single time has my ph gone up once soured.

May I suggest you try OYL-605 lacto (L Plantarum) from Omega Labs. You need to get a decent sour under your belt to get in your happy place with kettle sours. Make a starter with the lacto packet and keep it at 80F for two days. Keep it airtight and no stirring

I played with WLP001 and WLP029 yeasts before figuring I was wasting my money on the more expensive liquids. I rehydrate a sachet of Safale US-05 and pitch after it hit 3.2 ph. It takes off like a rocket and finishes nice and dry with a very neutral influence.

 

[napx]

Using a Jellas pH meter.

I tried WLP029 for my first attempt at a lacto beer before finding the forums here and milkthefunk and realizing that probiotics were a far better source for bugs.

Still no idea why the pH dropped so much after fermentation. Wish I knew exactly what I did wrong so it won't happen again . But oh well. Will give it another shot anyway.

I'd love to try a Gose next time around... any pointers?

 

[JosephN]

Here are my thoughts and opinions. When using sacc to ferment a beer, any beer and any sacc, the sacc will "lower the pH, but there will be a point in time when the pH starts raising again. If you leave the beer sitting on the yeast too long it can and will cause a rise in pH. This has been covered on The Jamil Show or Brewing With Style a few times. I made a Berliner a few weeks ago and used Giga yeast fast souring lacto. I let it go for 3 full days, and I used wlp001 to ferment it. When I tasted the wort after the first 3 days of souring I noticed a nice tart sourness, but after fermentation it was more malty and less sharp of a sour. However this all changed after I cooled the beer and carbonated to around 3-3.2 volumes. The higher carbonation level made the lacto pop and gives it a really crisp finish. This might also be part of the issue because a finished beer isn't the same out of the fermentor as it is on CO2.

I hope this helps some.