Berliner Weisse - over a month at 80+? Slow souring

[greaserdan]

First Berliner Weisse - Standard no boil, 50/50 Wheat and Pilsner Malt. OG 1.045.

I pitched a 1L starter of WLP677 (about a 1 week process) that tasted very sour and kept the fermenter around 80F with a heating pad. Two weeks later it was not very sour and the ph had only dropped slightly. I then pitched a 1L starter of WLP 672 (also 1 week) that also tasted very sour and kept the fermenter around 80 with the same heating pad. Saw pretty active airlock activity for a few days after. Two and half weeks later it was still not very sour and had a ph of around 3.8. I moved it to the attic where the temperature remains 95+ degrees, maybe even hotter. A little less than 2 weeks in the attic and it is around 3.5 ph.

My questions:
- This process seems awfully slow for a pre-fermentation souring. What's wrong?
- Is it ok to taste this wort after sitting for so long at room+ temperatures? Its not showing any signs of infection but it makes me nervous to have a wort sit this long without a yeast fermentation. No sanitizing process is THAT thorough to get everything.

What should I do now (or next time)?

 

[xico]

First Berliner Weisse - Standard no boil, 50/50 Wheat and Pilsner Malt. OG 1.045.

I pitched a 1L starter of WLP677 (about a 1 week process) that tasted very sour and kept the fermenter around 80F with a heating pad. Two weeks later it was not very sour and the ph had only dropped slightly. I then pitched a 1L starter of WLP 672 (also 1 week) that also tasted very sour and kept the fermenter around 80 with the same heating pad. Saw pretty active airlock activity for a few days after. Two and half weeks later it was still not very sour and had a ph of around 3.8. I moved it to the attic where the temperature remains 95+ degrees, maybe even hotter. A little less than 2 weeks in the attic and it is around 3.5 ph.

My questions:
- This process seems awfully slow for a pre-fermentation souring. What's wrong?
- Is it ok to taste this wort after sitting for so long at room+ temperatures? Its not showing any signs of infection but it makes me nervous to have a wort sit this long without a yeast fermentation. No sanitizing process is THAT thorough to get everything.

What should I do now (or next time)?

I'm not sure if this helps but I have a couple possible suggestions on how to proceed with the batch (don't dump it) and some ideas to consider for the next version. If the wheat was flaked and not malt then the bacteria may well be working on the slow food available. If it was malt then it should be working its way to final gravity soon.

With the pH that low I wouldn't worry about getting sick from tasting it. I would be more attentive to oxidizing the beer. I would minimize tasting unless you have a CO2 tank you can purge the air out of afterwards.

My only experience with lacto are from wild cultures I've built up for kettle sours. If you are looking for a quick sour beer I would humbly suggest you look into this process. I made a way too sour berliner weisse by building the culture (100g of malt and a wort starter of 1.035 kept at 100F with almost no headspace for O2) for 24-36 hours before brewday. I mashed, sparged boiled and pitched and waited three days.

The wait was because I wanted a puckering punch and didn't get it until then. Once it was brought up to 160F and a yeast was pitched to finish fermentation it was way to sour. I learned from an veteran brewer that the sourness we perceive in a young, warm, uncarbonated beer is muted compared to a cold fizzy beverage.

Somethings to learn from and adapt I hope.

 

[greaserdan]

Thanks xlco. This is very helpful.
The wheat was malted so maybe it's just a slow working lacto. I've heard that most commercial varieties aren't very aggressive or quick working.

 

[xico]

Please follow up and lets hear how it turns out.

 

[xico]

i just brewed a couple goses that i threw this culture into (one mash and one kettle sour). I kept it at 110 and had half my wort's initial sugars in 15 hours. Something else must be going on I think. How have things come?