Kettle Sour Help

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Rudeboy

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I want to make a Kettle Sour. I know some purists are against it but when people cut it down for being cheap and easy. I thought "Cheap? Easy? That sounds like me."

So not planning on hitting a style or cloning anything. If you're in Canada Russell's The Kettle Sour is about what I'm looking for. But not a clone just the ballpark. Nice tart lawnmower beer for summer.

I have read the BYO article, watched the Basic Brewing episode, and searched forums but some of the advice is contradictory or steps missed out entirely in one and emphasized in others. So I'm not sure of best practices.

So planning on 50% 2-Row, 50% white wheat for 1.050'ish wort. Normal mash and sparge. Using Wyeast 5335.

Question 1: Heat to 180 for 15 minutes to pasteurize, or boil quickly?

Question 2:Cool to 110 F, or 90 F? Is it important to keep it tight to 90 or can I bounce between 90 and 110 with no ill effects?

Question 3: CO2 blanket? I take it the Lacto will be working anaerobically, is a CO2 blanket necessary? Would boiling help de-oxygenate the wort?

Question 4: Some say to pre-acidify the water with bottled 88% Lactic acid to give the lactobacillus a head start, how much? What pH am I looking for at the pre-acidification stage.

Question 5: How long? 24 hours 48 hours? They say to taste but I don't think I'll be able to tell in a non-hopped sweet wort. What pH should I be looking for?

Question 6: If I get dirty diapers smell is it a dumper or will it change to something palatable over time?

Then boil add cascades to IBU's in the teens and ferment out with US-05. Does that sound good?

Thanks
Rudeboy
 
Hi Rudeboy,

I made a lot of sours with wyeast 5335. Yes, pasteurizing is enough. Lacto likes it warm if you keep it inside the recommended temperatures it will be fine. No need for a co2 blanket. Don't add any acid, the lacto will lower the ph it more than enough. I normally let the lacto work for 3 days. Why don't you sour in the fermentor, its even easier ?
 
Cross contamination concerns. Can heat sanitize with the boil in the kettle. Also going to add hops in the boil for IBU's in the teens after the souring and I'd worry they would suppress the lacto.

Thanks for the info.

Rudeboy
 
Rude boy, I'm trailing your efforts. Can you link me to some of the resources you have found?
 
Brewed yesterday. pH meter said 5.56 at room temp, but that was the first time I'm using a meter so I'm not sure of its' accuracy.

In keeping with the Cheap & Easy theme, no pre-acidification, no CO2 blanket, no starter.

Pitched one pack of Wyeast 5335 Lactobacillus buchneri, manufacture date of April 25, 2017.

Wyeast says 60-95 F. Michael Tonsmeire says 120 F. Basic Brewing says 120 F (although with a different strain). Milk the Funk's charts seem to suggest 100 F is best. I went with 100 F, because it's in the middle, it confirmed my preconceptions and they had charts.

I've tried to keep it around 100 F. It's holding it's temp pretty well. I have it on my stove and direct fire it every once and a while. Took it up to 110 f last night at 10:00 and only down to 88 F this morning at 7:00. Over shot to 120 F before work today. I hope the up and down doesn't have a detrimental effect.

I haven't lifted the lid but no bad smells coming from it yet. Planning on letting it go 48 hours from pitch then take pH reading, looking for 3.5.

Resources: Michael Tonsmeire in BYO. Jan/Feb 2016 "Overnight Acidification" and December 2016 "Hoppy Sour Beers". This is where I got the CO2 blanket and the pre-acidification from. Although on closer reading I think he recommends this if you have an unknown mixed source, like a handful of malt. I assume if you have a pure pitch of Lacto from White Labs or Wyeast you don't need that but he doesn't say.

Basic Brewing Video. October 31, 2016 "Fruity Tart 100% Rye Session Ales"

Milk the Funk Lactobacillus Wiki. http://www.milkthefunk.com/wiki/Lactobacillus Very good.

I'll update when out of the kettle and in fermenter (or down the drain). I'm interested to see how the US-05 does in the low pH environment.

Rudeboy
 
Great report, i think you made the right choice going with 100F. 120F seems excessive, i would be uncomfortable heating the lacto to this temperature. It might be effective if you do a "wild" starter with grain. Maybe it keeps the yeast and unwelcome bacteria at bay.
 
Hey there,

I suppose it's too late since you already started but I have some thoughts.

Some people cut down kettle sours only because they lack the depth of flavor that only a mixed fermentation can achieve. There's certainly truth to that but I think kettle sours have their place too since being cheap and easy goes a long way for availability.

Based on my reading Wyeast 5335 seems to produce only a mild sour and may be somewhat slow. Other strains (such as L. plantarum) can lower pH further, faster, and with less dependence on temperature (e.g. L. plantarum is great at room temp). Still, some people use 5335 and say it's great.
Note that 5335 is heterofermentive, meaning it may produce some alcohol, which will evaporate off in the subsequent boil.

Boiling the wort is the best option. Pasteurization can be hit-or-miss for removing unwanted microbes. Also as you already mentioned, it removes oxygen from the wort.

CO2 blanket isn't necessary but anything you can do to minimize oxygen exposure helps reduce risk of contamination with aerobic bacteria.

Preacidification with lactic or phosphoric acid to pH 4.5 is another precautionary step to minimize risk of contamination. Not necessary, but potentially helpful.

How long it takes to sour depends on the species of Lacto you are using, among other factors like the gravity, temperature, etc.
3.6 mildly sour
3.5 semi-sour
3.4 getting there
3.3 you got to like sours to be here
3.2 you got to LOVE sours to be here
Calibrate your pH meter every time you need to take a reading; it is the best way to get accurate measurements.

I think feces beer would go down the drain. I've never seen anyone say they kept it and got good results later.

I'd suggest rehydrating the yeast when you pitch it.

Cheers
 
The other benefit of pre-acidifying is to improve head retention. There's an enzyme that's active above 4.5 that will impact your head retention.
 
Well that did not work out at all. Calibrated my pH meter and tested known sample and it was pretty accurate.

24 hours no smell. 48 hours smelled a little sour but kinda pedo (which I did not add) only down to 5.2. Fairly thick white stringy pellicle. 72 hours (well 69 hours) only down to 5.0. I gotta boil (going away for our long weekend). Doesn't taste sour but hard to tell in sweet wort, tastes a little funky. Not unpleasant no Butyric Acid smell or taste.

Hopped with Cascade to 10 IBU pitched US-05.

So that was a fail. Gotta learn to lose before you learn to win, they say.

Gonna try and save this by adding bottled lactic after fermentation. There is something funky going on, so that and the bottled lactic should give me something like an easy drinking tart lawnmower beer I was looking for.

Things I'll do next time. Pre-acidify to 4.5. Make a starter. Keep it near 100 F don't let it get up to 120 F. Build in the possibility of longer than 72 hours for souring. One of the above resources said Wyeast Lactobacillus brevis 5223 works better for kettle sour but its a PC release and not available right now. I only really have a line on Wyeast products not White Labs or others.

I'll get it next time.

Rudeboy
 
I just made a hoppy kettle sour using Sour Weapon from Bootleg Biology (pedio strain) and it is fantastic! PH got down to 3.3 in 24 hours. Fermented with Funk Weapon #2, dry hopped with Belma and hibiscus. Next time I'll be trying to sour it with probiotic pills containing L. plantarum. Lots of people recommend using the pills since its a lot cheaper to use and no need for a starter with similar souring level/times.
 
Pretty sure the problem was your lacto species; 5335 isn't the best. On the other hand probiotics can be a great source of Lacto; no need to use lab cultures.

Adding bottled lactic acid is a bad idea, it probably won't taste good.

You might consider just keeping that batch around for a while and blending it with your next batch of sour! You could even add some oak cubes or something.
 
Is there a source of proven probiotics? How about brand names, amounts to pitch etc?
 
http://www.milkthefunk.com/wiki/Alternative_Bacteria_Sources
Anything with L. plantarum is commonly cited as working great (Goodbelly, Swansons). It sours quickly at room temperature, no need to heat.

http://sourbeerblog.com/lactobacillus-2-0-advanced-techniques-for-fast-souring-beer/
Pitch about 38 billion cells per gallon although you may get away with less. This isn't quite like pitching yeast. Under-pitching shouldn't create off-flavors but may take longer or increase risk of contamination. Published information is a bit lacking.

I've done one kettle sour and I used a blend of Lacto species in a probiotic (one of which was plantarum). I pitched enough pills to get at least 38 billion cells per gallon and got superb results.

Similar to lab cultures, try to find a fresh probiotic, and keep it refrigerated until use.
 
June 5 still only down to 4.54 pH. Gravity only down to 1.014. The S-05 was slow to start then had a weird krausen. Big soap bubbles. I think the pre souring point above is right I think all head will be lost on this one. Tastes ok, kinda funky, not sour at all. Added two drops 88% lactic to sample tasted ok but not even a tang. Added more really sour and fake tasting. Added 2 ml's lactic to the keg. No appreciable difference. Will wait for CO2 to settle and add another 2 ml's. The one thing the sample showed me is you can definitely go too far. I'm hoping there's some middle ground that's just right.

Why is pre-acidifying with bottled lacto good, but adding bottled lacto after bad?

I gotta say unless some one has a different process do not use 5335 for kettle souring.

Rudeboy
 
pH is a logarithmic scale and wort does have some buffering capacity.... It takes much less lactic acid to drop pH to 4.5 than to drop pH to 3.5. The artificial acid added doesnt contribute to taste as much because there is a lot less of it ... And microbes produce a bunch of flavor compounds that the lab just can't match.

Edit: also the bacteria and yeast munching away can clean up a lot of that chemical taste.

Don't be afraid to use some L. Plantarum for future sours. It's easy to use and works great. Like I said before, you might want to save that batch to blend with your next one instead of adding artificial acid to it.
 
I finally dove into kettle souring last year with great results right off the bat (especially since Goses and Berliners are two of my favorite styles in the summer). I did a bunch of research first and I'll tell you the cheapest and easiest way turned out to be the best for me.

First I made my own lacto starter from uncrushed grains ala the 5 Blades Brewing write up so that I would have a mix of cultures and a lot of cells going into my wort.
Link to Laco Starter
I definitely added seltzer to rid the flask airspace of O2 and pre-added some 88% lactic, not for flavor, but to minimize the growth of unwanted baddies in my starter. I also de-oxygenate the full mash as well using the same method. You don't need tons of lactic because you are just trying to get the pH down to a level where unwanted/harmful organisms can't grow.

Then I mashed/sparged the entire batch of wort in my cooler two days later, cooled to 100F, and pitched the lacto starter then left it next to a heating vent in a spare room, top sealed. Each morning for three mornings I checked the temp and it was down in the 92F range so I added a little boiling water just to bring it up a little bit. Keep in mind if you do keep the temp up in the 100F range yeast is not going to survive all that well if at all. If you were to get wild yeast in with your sour mash it would start converting the sugar to alcohol which would be boiled off later (substantially bringing down you ABV of the final product). If I remember correctly my OG was 1.036 and gravity after 3 days in the mash tun was 1.034 so, I know I had no mixed fermentation going on.

After 3 days I boiled for 15 minutes with my hop/salt/coriander addition. It is hard to judge the true sourness of a sweet wort so I just let it go 3 days as I thought that was a good average. Let me tell you, mine was a little stringy as well and smelled like 6 gallons of Campbell's tomato soup. I thought, this is going to be nasty, but what the hell, lets go for it. Most say that dirty diaper smell is a deal breaker and a dumper, but any other bad smell will dissipate with boil off, fermentation, and time.

Post fermentation it was delicious and super clean and refreshing. Tartness was on the level of any some decent commercial Beliners.

BTW, I now use this lacto starter process to do partial quick sours with some saisons I want to be dry and tart. I'll siphon off 3-4L preboil of a 6 gallon batch, and lacto sour for three days, boil and add back into my clean fermentation vessel with already fermenting saison batch. The result is a clean a subtly tart farmhouse that's really nice in the summer.
 
I wish my result end up like everyone else's in this post.

My kettle sour ended as an epic fail...

I used L. plantarum and it the resulting wort smelt incredibly bad after 48 hours. I went ahead and boiled and fermented but was tossed. The whole apartment reeked of it for weeks! The aroma could be best described as bile / stomach acid which pointed to too much Butyric acid from an infection i guess.

My fermentation freezer still carries the stench, two months after...

:(

Maybe I will work up the nerve to try again in the future because I do love sours.
 
I used L. plantarum and the resulting wort smelt incredibly bad after 48 hours. I went ahead and boiled and fermented but was tossed. The whole apartment reeked of it for weeks! The aroma could be best described as bile / stomach acid which pointed to too much Butyric acid from an infection i guess.

Did you boil your wort (and then cool it) before pitching lacto?
Did you pre-acidify?
Did you seal your kettle to prevent oxygen and bacterial contamination during the souring process?

These are the best ways to prevent wild bacteria some taking over. A starter would help as well, although it shouldn't be necessary as long as you pitch an appropriate cell count for your volume of wort.

Cheers
 
1. Yes
2. No
3. Nope. Just a kettle lid on the kettle. Not really sealed or weighed down. I think this was the big down fall.

Did you boil your wort (and then cool it) before pitching lacto?
Did you pre-acidify?
Did you seal your kettle to prevent oxygen and bacterial contamination during the souring process?

These are the best ways to prevent wild bacteria some taking over. A starter would help as well, although it shouldn't be necessary as long as you pitch an appropriate cell count for your volume of wort.

Cheers
 
I gotta say unless some one has a different process do not use 5335 for kettle souring.

Rudeboy

I learned the hard way myself. Dumped batch.

Once I shifted to Omega OYL-605 my results have been consistently 100%. Swanson L Plantarum caps are a secondary source of lacto if you want to try alternative methods.
 
I just did my first kettle sour and it was successful. Did the following:

1. Mashed normally, drained into kettle
2. Lowered wort ph to 4.4 using lactic acid to prevent other microorganisms and maintain proteins, measured with ph strips
3. Didn't pasteurize more than the mash itself should have
4. Transferred back to mash tun for souring in order to hold around 110 degress for as long as possible
5. Pitched 2 Goodbelly straightshots that are full of L. Plantarum
6. Waited 24 hours before boiling and pitching a blend of Bell Saison, 3724, and WLP 644

Bottled yesterday and it tastes like sour pineapple juice. I'll probably do the exact same method for future sours except I'll probably cold sparge a bit to get to 110 degrees faster.
 
3. Didn't pasteurize more than the mash itself should have

A very short boil will kill *all* the microbes. Pasteurization kills *almost all* of the microbes, so there is still a risk of contamination with wild bacteria.
Of course the wild bacteria might be fine, but it's still an unnecessary risk of producing off- flavors.

Spores (such as Clostridium botulinum) may survive a boil but they are generally killed by acid (pH<4.6).

Cheers
 
I've done three kettle sours and they have been ok. I still need to improve recipe and process.

Things that I would recommend:
1) Boil the wort for 10 - 15 minutes after mashing. This kills almost all bugs.
2) Preacidify to 4.5 using lactic acid. This will prevent contamination
3) Purge all O2 out of the boiled wort. For the first batch I used a keg and blew C02 through the dip tube and installed an airlock on the gas side. Purged for about 2 minutes.
4) I've tested serveral lacto alternatives. L.Plantarum pills (Swanson), yogurth, probiotic drink Yakult Casei Shirota. For the last batch I used starters from L.Plantarum and Casei Shirota to give it more "complexity"... I just liked the taste of the starters and the souring speed.
5) Monitor your PH and boil when you have your desired acidity (3.5-3.2). first batch took 72hrs and 3rd batch only 36hrs
6) Boil and hop. Keep IBU's under 15, I did not like sour and bitter taste together. If you want hop flavor, dryhop. I would suggest a 60min boil to eliminate any DMS.
7) I've been able to ferment ok with US-05 and Belle Saison. Make sure you rehydrate, I used two packs so double the yeast, as an insurance.

Hope this info is somewhat helpful.
 
Great tips!
Also forgot to mention boiling after the mash removes oxygen, further reducing contamination risk (and reducing oxidation during the souring process).
 
A very short boil will kill *all* the microbes. Pasteurization kills *almost all* of the microbes, so there is still a risk of contamination with wild bacteria.
Of course the wild bacteria might be fine, but it's still an unnecessary risk of producing off- flavors.

Spores (such as Clostridium botulinum) may survive a boil but they are generally killed by acid (pH<4.6).

Cheers

Part of the reason I lowered the pH! A short boil also carries the risk of DMS without enough time to drive it off, but there is no risk of DMS if you don't boil. I would argue that the lowered pH, heat of the mash, and a significant amount of hardy bacteria is plenty to get the sour done without off flavors. Others may opt to do more thorough kill step by boiling, but I'm just sharing what worked for me just recently.
 
I think DMS is created during the mash, but regardless the post-sour boil will remove it as normal.

Glad your process works! You might be right about overkill, just depends how comfortable you are with chancing wild bacteria. Some brewers ferment sours with only wild bacteria and usually get good results although less consistent & predictable. YMMV.

Rock on!
 
I think DMS is created during the mash, but regardless the post-sour boil will remove it as normal.

Glad your process works! You might be right about overkill, just depends how comfortable you are with chancing wild bacteria. Some brewers ferment sours with only wild bacteria and usually get good results although less consistent & predictable. YMMV.

Rock on!

I think the majority of DMS is formed and then driven off as the boil starts, and it isn't produced in significant amounts otherwise. I could be wrong though. That is a good point about it just getting driven off anyway when you boil it later, silly me. I definitely take more care with contaminants when I start primary fermentation, but because I'm boiling the kettle sour wort after 24 hours I just care that the souring happens without off flavors, and it at least seemed to work that one time. We'll see about next time . . .
 
My first kettle sour went terribly wrong. It was like sewage before the boil and vomit after the boil. That one went down the toilet. I was dumb enough to try again and I think it worked this time but IDK what it should actually smell like. It's been 2 days and I would say it has a vitamin/damp basement smell. Is that good? I haven't checked the PH yet.
 
Sounds ok to me. Vomit or feces would be the unrecoverable bad smells/flavors from what I've read.

There are a few relatively simple precautions outlined in this thread that will all but eliminate the possibility of contamination.

Probably want to check the pH at this point with a calibrated pH meter if available.
 
Has anyone had any ill effects equipment wise after kettle souring? I am in process of doing my first sour and just transferred to primary tonight. I've got all of my hoses and kettle soaking overnight in PBW but I'm still worried about potential contamination on a future batch.

Quick run down on my process -

- BIAB electric kettle - mash process completed here
- transferred to an old kettle, co2 blanket, pitched 8oz of unmilled 2row in a muslin bag, and laid plastic on top of the surface of the wort
- kept kettle in garage the last 4 days with ambient temps around 85-90. pH was 3.36 today. Definitely did its job as it was disgusting when I opened the kettle up but no horrendous smell.
- transferred back to primary kettle and did a 20 minute boil, hop addition. then transferred to carboy.

Shouldn't be any problems with the primary equipment since I did boil right? Should I do a boil in the kettle I soured in to be safe as well?

Appreciate any help!
 
Generally for a home brew kettle sour, the bacteria are added to wort in the boiling kettle (hence the name), which is then sterilized afterwards during the boil.... And no other equipment is used besides taking a pH reading. Elimination of risk of future contamination is half the advantage to kettle souring.

In your scenario, the kettle in which you did the sour, as well as any equipment used to transfer the wort with live bacteria into your boiling kettle might contaminate future batches if it comes into contact with cold-side wort.... Especially since you used wild bacteria.
As long as you clean your equipment it might be fine. I don't think anyone can really tell you how big a risk there is of future contamination but most people seem to prefer to play it safe.

Unrelated but a 20-minute boil sounds short, is that what you'd normally do?
 
Thanks, I've already went ahead and dedicated the tubing I used for the transfer as "sour only" and the kettle I actually soured in I plan on adding a heating element and be able to dedicate for souring and do a true kettle sour process.

20 minutes is definitely not my typical time but I have been going 30 - 45 minutes for the last 6 months with no issues. I was strapped for time yesterday and remembered the xBmt about the short and shoddy process so I was like why not.
 
I soured 5 gallons in a glass carboy with a ziplock bag tied tightly over the top. Left it in my garage where the temp stayed between 85-100. Today is day 3 and the PH is at 3.5. :D
 
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