Kettle Sour Issues

[Morrey]

Brewed a kettle sour and was epic fail. 50/50 wheat and pils base. Made starter with lacto from white labs brevis 672. Starter in 1L with airlock, no stir. Pitched in kettle after mashout, OG 1.049, 80F, but before lacto pitch, brought wort to 180F to ensure bacterial control and added lactic to start at 4.5ph. Souring went well and got to 3.8ph. Then wort started losing sweetness never getting below 3.8ph. My goal was 3.4. I tested my gravity and was at 1.010. This sucker was fermenting out on me. What in the world? I am "Mr Sanitizer" but it looks like yeast in my wort. And it had to be a fairly active fermentation to bring the wort from 1.049 to 1.010 in 2.5 days at 75F.

What went wrong here? I was planning to pitch yeast after I boiled the soured wort but never got to that point.

 

[Morrey]

Does anyone have a similar experience that yeast seems to have contaminated their White Labs lacto culture?

 

[KeyWestBrewing]

No experience but I remember reading this which says lacto can't ferment out like that.

http://www.milkthefunk.com/wiki/100%_Lactobacillus_Fermentation

 

[mattd2]

The WL catalogue notes that all cultures are intended to inoculate a secondary fermentation, i.e. they are not intended for kettle souring. The reason I can see for this is they are not going to guarantee that there is no yeast in the package.
http://www.whitelabs.com/sites/default/files/WL_catalog_2015.pdf

 

[Morrey]

The WL catalogue notes that all cultures are intended to inoculate a secondary fermentation, i.e. they are not intended for kettle souring. The reason I can see for this is they are not going to guarantee that there is no yeast in the package.

Good point. Time to shift labs. Like Key West noted, lacto will not ferment out like happened to me. That was some pretty active yeast to do that!

 

[crane]

Both white labs and wyeast are known for not selling pure lacto cultures so you can't use their products for kettle souring. I've had good luck with omega yeast's fast souring lacto blend.

Others have had good luck using Swanson's probiotic pills or good belly probiotic shots.

 

[Morrey]

Both white labs and wyeast are known for not selling pure lacto cultures so you can't use their products for kettle souring. I've had good luck with omega yeast's fast souring lacto blend.

Others have had good luck using Swanson's probiotic pills or good belly probiotic shots.

Good feedback, and after additional reading, I see others steer away from these two lab's lacto cultures for this very reason. I was a bit worried about ordering Omega OYL-605 in this summer heat. No worries as opposed to yeast was the response from Omega, so two packets ordered today. One wasted beer batch was down the tubes with a contaminated lacto culture...lesson learned.

Do you recall how long the souring time took? I will pitch from a starter and incubate about 90F ambient in my summer heat wave brew cave.

 

[crane]

I pitched into 110f wort, but let that drop to room temp 75-80f. I dropped the pH to 4.5 with lactic acid prior to pitching the bugs. After 3 days it was down to a pH of 3.2

 

[Sourz4life]

Take a look at Milk the Funks page and facebook. Alot of good info for this stuff. Could use good belly which is a drink people use which is just pure lacto, I forget which strain though. I'm not sure if this is something you can do but if you have a lab set or someone with it they can bank the lacto and then look at it and see if you've got yeast in there. If so you could separate them using an agar plate.