[edvinjonsson]

So I did the quick souring method as I read on zymurgy and some forums. 2 liter starter with some grains kept at 100-120 F for 3 days, then put that in the wort and kept at around 100F. Its been 2 days right now and it seems like there's a 3/4'' krausen on top of the wort, not a pellicle, it looks more like a normal yeast krausen, and there's a lot of airlock activity. Is this normal?. I took a sample, and the pH is down to 3.9, and gravity is down from 1.055 to 1.044. It smells kinda like sauerkraut, and tastes somewhat sweet and sour, pretty nice actually. Would the beer be noticeably sour if I boil, chill and ferment normally at this pH? Or should I wait for the pH to drop further? Also, should I boil or just pasteurize?

[kramerog]

Lactobacillus, IIRC, emit CO2 and lactic acid.  What kind of beer are you trying to make?  The gravity drop is pretty substantial.  IIRC, I did a Berliner Weiss that had a pH of 3.9; fairly sour and refreshing, but not sour enough for the style.  Lacto will survive a 140 deg pasteurization so if you pasteurize you want to hit at least 170 F.

[brewsumore]

I used the sour worting procedure once, successfully thank goodness.  I had read that the malt-based lacto introduction sometimes results in a big specific gravity drop that you are experiencing by souring your mash/sparge runoff, I believe based on creating an aerobic reproduction cycle vs. anaerobic reproduction.  I'm sorry I don't recall the specifics.  It was enough of a risk, and purportedly avoidable by inoculating the starter with a commercial lacto strain (Wyeast), that decided me to use the commercial strain.  The problem is that any alcohol created by the lacto starter souring process (if that indeed occurs) is lost when you boil the wort with hop additions.  So, the starting gravity of your beer will be the final gravity after the starter is done souring the runoff, although it will increase just slightly due to evaporation during the boil.  You will end up with a low ABV beer after the beer yeast fermentation.

When I added my sour starter my runoff was at 1.053.  When soured after 67 hours, the SG was 1.050, but part of the drop I attributed to adding the 1/2 gallon 1.033 lacto starter.  For my situation I added 10 oz. of DME, and ended up with an OG of 1.057 for 11 gallons after a 90 minute boil.

Sounds like you have a good degree of sour in your wort so go ahead and boil with hop additions when you're ready, and I would calculate how much DME or LME you need to add to bring your wort up to a proper starting gravity prior to inoculating with brewer's yeast.

[Jimmy K]

What sort of container is it in? You want to eliminate oxygen from your wort while it is souring to inhibit other organisms. Boiling to kill the lacto and then adding ale yeast to complete fermentation is a common method. Most berliner weisses I've had were soured from 24-36 hours.

[kylekohlmorgen]

The level of sourness won't change during the boil, but boiling will stop the souring. When it tastes sour enough for your liking, boil and ferment as normal.

To kill off all organisms, you can just bring it up to a simmer and then cool it right back down.

[edvinjonsson]

Thanks a lot. I boiled with the hop additions before I pitch the lacto starter, so I just wanted to kill all organisms. I ended up boiling for 5 minutes at that point, and pitching the ale yeast. I did add a bit more extract to bring the gravity up a bit, and am planning on adding raspberries after primary. Just wanted to know if it was gonna taste more sour after fermentation, or if it was gonna stay that way. Anyway I hope it turns out alright, this is my first time messing with bugs. 

[brewsumore]

Yep, as previously stated it won't sour anymore once you boil after the wort is soured.  I hope you got a level of sour you like.  I felt my 67 hours was just right for my tastes.

[tom]

What type of sour beer are you making?
German Berliner Weisses are 3.0-3.2 pH.

[kylekohlmorgen]

pH doesn't matter. Its all about how much acidity you want in the flavor of the beer.

I usually don't take pH readings of my finished beers, just so I don't have any preconceived ideas of what the beer tastes like before I actually taste it.

[mabrungard]

One of my fellow FBI members has been quite successful with sour beers and this sort of souring treatment.  He mentions that you have to let the initial grain and water ferment go for several days.  Apparently the various populations of microbes compete, with the lactic bacteria finally out-acidifying the others and killing the others off.  The aroma of this competition changes over time.  Its kind of rank at points, but finally settles into that smooth sour lactic aroma.  Its at that stage that you want to pitch it into a major volume of wort.  The natural selection will have already run its course.

[tom]

pH doesn't matter. Its all about how much acidity you want in the flavor of the beer.

That's certainly one way of doing it.

[drjones]

Based on a recent read of Kristen Burton's 2010 MA thesis ("The Citie Calls for Beer: the introduction of hops and the foundation of industrial brewing in London 1200-1700" - highly recommended) I just attempted a traditional unhopped, unboiled (yes) ale.  This experiment consisted of 2 pounds of Crisp ale malt, mashed (150F) and sparged to produce a roughly 2-gallon wort at 1030.  This was cooled and then pitched with a half pack of dry California ale yeast (because it was handy).  I've heard of similar no-boil approaches to making Berliner Weiss.  I expect this unboiled wort to produce lacto and a notable sourness in a week or so.  I'm three days into the fermentation now - it is very active and looks "normal" (it is basically a cloudy 2-gallon yeast starter at this point).
Have any other brave souls tried this?  The traditional, unhopped ales noted in the thesis did not last long - I expect this one will also require rather quick consumption before it spoils!  I just hope it settles out before going rotten...

[kramerog]

Based on a recent read of Kristen Burton's 2010 MA thesis ("The Citie Calls for Beer: the introduction of hops and the foundation of industrial brewing in London 1200-1700" - highly recommended) I just attempted a traditional unhopped, unboiled (yes) ale.  This experiment consisted of 2 pounds of Crisp ale malt, mashed (150F) and sparged to produce a roughly 2-gallon wort at 1030.  This was cooled and then pitched with a half pack of dry California ale yeast (because it was handy).  I've heard of similar no-boil approaches to making Berliner Weiss.  I expect this unboiled wort to produce lacto and a notable sourness in a week or so.  I'm three days into the fermentation now - it is very active and looks "normal" (it is basically a cloudy 2-gallon yeast starter at this point).
Have any other brave souls tried this?  The traditional, unhopped ales noted in the thesis did not last long - I expect this one will also require rather quick consumption before it spoils!  I just hope it settles out before going rotten...

Here's a link: http://dc.library.okstate.edu/cdm/singleitem/collection/theses/id/2657/rec/9

I've done a no boil Berliner Weiss using a lacto culture from Wyeast.  It was pretty stable with standard sanitization techniques and without refrigeration over the two months it took for me to drink it up.

[kylekohlmorgen]

I've been doing the same thing in principle for my last few sours. I double-batch into the kettle, heat to a near-boil (200F+), and (before adding hops) pull off half. I cool this half to about 100F while proceeding with the other half as normal.

I change up the bugs going into the sour batch, but it always includes a nice, healthy pitch of Wyeast lacto from a culture I keep going in a growler. My last batch (from a saison/wheat-type grist) was pleasantly sour after a week with just lacto and a small dash of mixed culture (lacto, various bretta, sherry flor).

Not the most complex beer in the world, its a lot like unsweetened lemonade. I'm hoping it will be a knockout with a few gallons of unsweetened cranberry or blackberry juice.

[edvinjonsson]

It's been fermenting REALLY vigorously for 5 days now, at 68F. I wonder if I didn't kill the bugs.