Did I cook my lacto?

[stz]

Hello HBT.
Decided to try my first experiment with a sour. Mashed a bit more grain than usual for a .041 beer, sparged for the normal beer at 80C, continued collecting until I had another 19L @ .019 or so. Ran straight into a freshly sanitised container containing some table sugar bringing it up to .026, dosed it with about 20ml of 88% lactic acid. Left this to cool until the evening when it felt warm to the touch and then dumped in the contents of 6x lactobacillus plantarum supplements quoting 2 billion cells per capsule.

This was almost 84 hours ago now and nothing, no change in gravity, no change in taste, no sign of anything occurring. I've just dumped in another 14 capsules. What should I expect here? I was more concerned with yeast contamination due to the lack of a boil?

 

[doomy86]

Hi stz, at what temperature are you souring?

 

[stz]

Hi Doomy. I 'pitched' about 8 hours after sparging at 80C so I'd estimate the wort to have been above body temperature and it certainly felt warm to the touch. I would not have guessed it to be above 50C though which is the point where I'd have been concerned it was too hot. I placed it into my fermentation chamber (chest freezer) and ambient is about 25-26C at the moment. The following day the chamber still felt above body temperature still though it wasn't heated. My intent was for it to stay warm for at least 48 hours and that to be long enough to get the job done.

I sampled it today 24 hours after the larger (3x) repitch and it is definitely starting to show signs of being tangy. At this point it is no warmer than ambient (26C). I don't have any prior experience, I suppose my initial pitch was very low, perhaps too low to get the job done and maybe my increased pitch is what has done it, that or just simply time.

Commercial plantarum cultures designed for 19L of wort say things like 150 billion cells. My initial pitch would have only been 12 billion. My repitch brings that up to 40 billion. Other strains seem to get the job done with significantly less cells than plantarum. I just figured that exponential growth would get me there in short order with division every 15 minutes.

 

[doomy86]

Your plan is well thought out. Just measure the temperature before pitching next time. Some lacto cultures like it very warm. Well above room temperature. I once did a sour at room temp and for 2 days nothing happened. Only after raising to 35C the lacto started working.

 

[stz]

As an update today the wort is significantly more tangy, it isn't verging on tart or sour, but it is definitely at a point where I would be quite happy to brew with it. It is difficult to tell because it is still very sweet with unfermented sugars so my inexperience leaves me concerned that after normal fermentation the final 'dryness' of the beer might mean it actually ends up being very sour.

I guess there is where accurate pH measurements come into it, though I can't really be bothered to start messing around with my feeble book of test strips.

I'm going to brew it tomorrow and hope that it hasn't passed a point of no return by then, it isn't particularly warm at the moment, low/mid 20's.

What would be useful is if anybody has experimented in this way before did they find that once the wort starts to taste tangy the finished beer was quite sour enough, or did they find that the perceived sourness was about the same?

I recently had a delicious lemon gose which was a brilliant summer drop, bright, refreshing, palette cleansing and acidic without being too horrifically sour. I've had a margarita (lime) gose which again was just on the right side of fresh and delicious. I had a cherry gose which was a little more brutal. I've had berliner weiss which started to cross the line into difficult to quaff due to being genuinely sour and I can see why people add a shot of syrup to it when serving. I also had a gooseberry sour IPA which made me genuinely fear for my tooth enamel. At the moment the perceived sourness of my wort is a little weaker than the first beers I mentioned which is why I'm happy to brew it tomorrow, but I imagine left until the weekend it could be something which wants blending? I quite like sour beer, but when it is challenging to drink I fear making a regular sized batch.

I read that most people prefer a pH of 3.5-4 and plantarum tends to crap out around 3.3 or so. I'm not too fussed as a result because I'll just make a minor dilution during the boil if I've gone too far. It'd just be good to hear if people have found that tangy pre boil = brutal post fermentation.

My objectives here was to take something of limited value (extra process wort) and start to learn what happens, what that tastes like and develop my processes.

 

[stz]

What a difference a day makes. This afternoon the wort was physically slimy, a bit gooey and scattered with brown feathery clumps of material. Taste was slightly sharp, mostly tangy but very clean though a little grainy.

Currently coming to the boil with enough wheat and extra light DME to bring it up to 44 pre boil. Expect to gain two points. 10g herkules FWH. 10g cascade at knockout. Fermenting at 17C with a mixture of S04 and nottingham.

 

[trav77]

Have you seen this?
http://www.whitelabs.com/sites/default/files/R&D Wild Yeast and Bacteria Experiments.pdf

Not much background info as to their methods but I take a couple things away from it: L. plantarum seems to have a longer lag phase than other lacto species when cool (although their "cool' is still significantly warmer than your ambient). Also, pH seems to plateau at a higher pH when fermented warmer @ 110 (which is not relevant to your situation...).

Hope it turns out. I'm planning a kettle sour soon - something with a nice fruity dry hop.

 

[stz]

Thanks for the spreadsheet, I've saved it because I'm sure I will refer back to it. Ideally something like that was supposed to happen (almost there by 48 hours). Instead I had 'tangy tasting' at 144 hours. I'm disheartened that no other chart shows anything other than 'done' by about 72 hours, but then my culture was derived from a probiotic. My pitch rate was very low. My temperature was lower than optimal. So if I produce palatable beer I will consider this experiment a great success. Maybe in the future I will bother with the narrow range pH test strips. Maybe I will take samples into work to test with the pH meter.

I still have questions if anybody knowledgeable can weigh in?

- The appearance of the wort pre boil was quite strange. Whatever was going on was not producing co2 or gravity drop or another other classic signs of fermentation, but there was something happening (strands of alien like goo, brown fluffy clumping). I don't know when to rejoice and when to ditch something (it tasted ok).
- The wort was tangy and slightly sharp though still very sweet. Does the perception of this increase once the beer is 'done' fermenting? Obviously the pH of finished beer is much lower than the pH post boil and in the interest of pedantry post boil is lower than pre boil and the mash lower than the liquor still, but for future reference, I would like to know when to stop the souring.

Oh and on hops/dry hop etc. Man I was itching to let lose with the hops. I was hoping to have it sour by sunday last week when I could have really put some effort into the recipe design, but instead I'm brewing after work on a Thursday. All the way home I was thinking of what to do, handful of noble hops for bittering? Any aroma hops? Go crazy with the big american hops? what about some Aus or NZ varieties?

When I saw the wort looking so sickly I thought ok, I'm going back to basics here in case it isn't actually drinkable. Budget bittering addition and small cascade during whirlpool because I've quite a lot of cascade. I've nelson sav, vic secret, motueka, galaxy, mosaic, citra, amerillo, centennial, simcoe, columbus, maderina bavaria and others all on ice.

 

[trav77]

Oh and on hops/dry hop etc. Man I was itching to let lose with the hops. I was hoping to have it sour by sunday last week when I could have really put some effort into the recipe design, but instead I'm brewing after work on a Thursday. All the way home I was thinking of what to do, handful of noble hops for bittering? Any aroma hops? Go crazy with the big american hops? what about some Aus or NZ varieties?

When I saw the wort looking so sickly I thought ok, I'm going back to basics here in case it isn't actually drinkable. Budget bittering addition and small cascade during whirlpool because I've quite a lot of cascade. I've nelson sav, vic secret, motueka, galaxy, mosaic, citra, amerillo, centennial, simcoe, columbus, maderina bavaria and others all on ice.

There's a brewery near me that does various kettle sours with a good dose of late/dry hops... usually fruity/tropical US and NZ hops. I really enjoy them and that's what I was thinking for my next one. So I think a lot of your options above would be really good.

I would stay away from much on the early end. Bitterness and acid really clash.

 

[stz]

I've got the current experiment fermenting at the moment, it is very slow especially as it is double the usual pitch rate though I am fermenting at around 17-18C which I consider on the low side. I might re-pitch this if it doesn't start looking a little more lively by this afternoon.

I've taken off another 25L of process wort yesterday and done the same as before. This time I took a mash pH (5.47), pH after the sparge (5.57) and dropped it to a measured 4.4 with 88% lactic. Temperature before adding my plantarum was 42C and I added a lot more, like 50 billion cells according to the packaging.

Hopefully if it sours in a similar manner or a little faster my experiment will be 90% through fermentation before I have to make the decision as to proceed to the boil, if things are favourable I might be bold enough to let this one go a little longer and use a few more adventurous hops.

 

[trav77]

Sounds promising. Go metric system!

 

[stz]

The first experiment is pretty finished though it has a lot of yeast in suspension and was still around 015 on wednedsay. I roused it up and increased the temperature by a degree. The perceived sourness is significantly greater now it is almost fully fermented out. The beer is problematic though as it is quite bitter and the bitterness as suggested here and by others (of course I always think I know best I guess) is quite unpleasant. I'm going to give it some brett and leave it to age out and see what I get, no great loss, though I would not use much bittering hops for the sake of it in a hurry.

My second 'experiment' was much sourer after three days. It did not get slimy/stringy or develop any floating chunks like the first. For this I mashed some wheat with a smaller amount of rye and performed a 45 minute boil with the sour wort using no bittering hops. After setting a whirlpool going through the plate chiller I added 10g of lemon zest, 10g lime zest, 10g sea salt, a handful total of mostly manderina bavaria, citra and mosaic. I will dry hop this one if it comes out well. It got a double pitch of US05.