How to succeed at sour mash?

[joshesmusica]

I really am starting to like sour beers. But I wouldn't mind having only a bit of the sour if it meant that I didn't have to wait a year to get it.
Been thinking about the concept of souring the mash. While I read that it's possible to do it this way, and brew dogs even did on their show, I'm wondering if anybody's had any success with it, and what exactly your process was.

 

[iijakii]

Everything I've read states that there's three main things that help:

• Keep the temp at 100-110F so the lacto can go nuts.
• Minimize oxygen. Supposedly it can lead to some nasty aromas if you get lots of oxygen. Most cover the mash with saran wrap, some go so far as to purge with CO2.
• And lastly, getting the pH down quickly to avoid other things taking growth. Whether you pitch a healthy lacto starter or use some acid/acidmalt after the mash.

I'm going to try my first sour kettle (not souring in the mash, going to drain/sparge and then sour) this Sunday, will report back my experiences and hope it helps.

 

[joshesmusica]

so you're doing the mash, and then letting it cool down to 100-110F and then keeping it at that temp? for how long?
how low a ph are you talking?
what do you mean by souring in the kettle?

 

[aprichman]

Everything I've read states that there's three main things that help:

• Keep the temp at 100-110F so the lacto can go nuts.
• Minimize oxygen. Supposedly it can lead to some nasty aromas if you get lots of oxygen. Most cover the mash with saran wrap, some go so far as to purge with CO2.
• And lastly, getting the pH down quickly to avoid other things taking growth. Whether you pitch a healthy lacto starter or use some acid/acidmalt after the mash.

I'm going to try my first sour kettle (not souring in the mash, going to drain/sparge and then sour) this Sunday, will report back my experiences and hope it helps.

One time I left my spent grains in my cooler mash tun for 2 days because I came down with a cold. When I opened it up one of the most disgusting smells I have ever experienced had developed.

 

[pdxal]

Sour mash is simple- mash, cool down to 110-120, pitch some raw malt onto it, cover with saran wrap and maintain the warm temp for 24-48 hours and you'll end up with a sour wort that can then be boiled/hopped after sparging and have regular yeast pitched to ferment.

 

[Black Island Brewer]

Another option is to sour the wort. My first Berliner Weisse was done this way: mash as normal, cool slightly, then rack into a 5 gallon carboy on top of a pound of unmilled wheat malt. Top off to within an inch of the top of the carboy, then cap it with a plastic wrap covered drilled bung. Hold at 110F (I did this in my temp controlled freezer), tasting daily until desired sourness. Mine took 2 days. The souring process did overflow the carboy a bit, but I got no vomit or diaper aromas or flavors (a known problem).

 

[Swab]

Is it possible to sour mash using an electric setup? Just set the pid to 110 and walk away for a couple of days?

 

[stpug]

You need to pick your temperature based on the strain of lacto you're using. You may be served better in the 80s or 90s depending on strain.

 

[revco]

I've done a couple and what I'll tell you is that it's slightly different from a typical sour. It tends to be really "clean" in nature, not "funky" like a lot of sours are. That said, it is a quick way to get a beer to sour up.

Basically, the gist is mentioned above, but you can let the lacto stay above 90 (to prevent other bugs from taking hold) for some time, usually 60-72 hours, to increase the levels of sourness. I prefer to add pure lacto, rather than just grain, to help get the lacto culture going. After it's done souring, you proceed as normal with the sparge and boil. Keep in mind this will kill all the lacto so the beer will never get more sour or funky from the time you boil it, unlike a regular sour.

What I learned from my first is I had to add a few cups of boiling water to the mash every 24 hours or so to maintain a temp over 90. This means that most people who use the cooler method should probably mash a little thin up front to allow these water additions.

Other than that, and the good advice above, I find it to be a pretty enjoyable method. I strongly prefer regular sours, but this works to experiment a bit, in a pinch or if you just don't have the patience to wait out a proper sour.

Have fun!

 

[joshesmusica]

Nice thanks guys! I'm pretty sure I'm going this route on the next batch! Prolly gonna go with the Berliner weisse. Got a good recipe for that? Has anybody ever tried this with an IPA?

 

[madscientist451]

The sour hour podcast episode #4 had a good explanation about kettle souring. I believe they used a Co2 "Blanket" technique and kept the temperature above 100 for 48 hrs. I think they pitched a specific lacto strain instead of getting it off of unmilled grain, but its been a while and can't remember all the fine points.
I prefer after boil souring, the sour character seems smoother to me than doing mash or kettle souring.

 

[Natdavis777]

My first sour mash, I mashed, cooled to 90F, drained to two fermentation buckets @ 90F, threw in some unmalted grain, purged with co2, then set the buckets in my garage attic (reason for using the buckets, attic maintained 90F+ temps) took 3 days to really sour. I then boiled, fermented with 05, and kegged. I didnt purge well enough with co2 during the sour mash, as many people said it had a stinky foot aroma (most likely acetobactar from either not high enough temps, or o2 presence).

Currently on my second go round. Did a quick extract brew, cooled to 90F, transerred to carboy, pitched lacto brevis, and set the ferm chamber to 110F. I think I killed my bacteria, as it only soured a bit, and really didnt attenuate. Later found out Brevis doesnt like 110F, but more 90F. I plan to blend this sour mix with my lambics. A few days ago, I swirled the carboy up real well, and am currently cooling a sample to see if my interventions have worked, if not, looks like Im pitching more lacto then.

But back to your original question, iijakii hit the nail on the head with his 3 suggestions.

 

[iijakii]

So I started this Sunday afternoon, the sour is going well. I think I'm only more in the high 90s, not quite 100-110F range. But it's starting to tart up nice, will let it go 1 or 2 more days most likely. I just have it in a bucket, no CO2 purge or anything. I did bring it up to 200 or so for a bit, then had a n apple juice starter.

 

[joshesmusica]

Yeah so basically the idea is to just keep tasting the mash until it's sour enough and then do the boil as normal? Also you mentioned that it needs lower ph? So if I was going to sour a brown would that bring the ph low enough if I'm normally in the 5.7 range for pales?

 

[stpug]

Yeah so basically the idea is to just keep tasting the mash until it's sour enough and then do the boil as normal? Also you mentioned that it needs lower ph? So if I was going to sour a brown would that bring the ph low enough if I'm normally in the 5.7 range for pales?

If you use a heterofermentative lacto bacteria then it will produce alcohol as well as lactic acid and co2. If you then proceed to boil this you will boil off some/most of the alcohol that has been created. If you want the LAB dead then you can simply heat to ~175F and by the time you get there the LAB will be dead, then quickly cool.

If you use a homofermentative lacto strain then boiling would be fine afterwards since it doesn't (should not) create an ethanol.

As for lower mash ph, if you can bring your primary wort to about a 4.5pH prior to inoculating with your LAB then you can provide yourself some protection against other bugs taking hold, most particularly those ones that create the nasty odors.

 

[iijakii]

I have a question on lacto/brett and DMS. I have a 60/40 pils and wheat sour mash going right now. ABV is nearing 7%. Should I still do a long boil since there's a good amount of pilsner? I know some people do either no or short boil Berliners, but I'm not too familiar with why they can get away with that.

 

[joshesmusica]

If you use a heterofermentative lacto bacteria then it will produce alcohol as well as lactic acid and co2. If you then proceed to boil this you will boil off some/most of the alcohol that has been created. If you want the LAB dead then you can simply heat to ~175F and by the time you get there the LAB will be dead, then quickly cool.



If you use a homofermentative lacto strain then boiling would be fine afterwards since it doesn't (should not) create an ethanol.



As for lower mash ph, if you can bring your primary wort to about a 4.5pH prior to inoculating with your LAB then you can provide yourself some protection against other bugs taking hold, most particularly those ones that create the nasty odors.

So if no boil afterward, should I be doing the souring after I've done my boil? I guess I'm confused about the souring of the mash then... I thought you just mashed like normal then added some grains in order to get some lacto in there, then after a couple of days (or however long it takes to get the sour you're looking for) proceding as normal.
Or if I was to just do the souring pre boil, would I just want to attempt to take this into account when making the recipe? It's not going to ferment a huge portion of the wort will it?

 

[stpug]

So if no boil afterward, should I be doing the souring after I've done my boil? I guess I'm confused about the souring of the mash then... I thought you just mashed like normal then added some grains in order to get some lacto in there, then after a couple of days (or however long it takes to get the sour you're looking for) proceding as normal.
Or if I was to just do the souring pre boil, would I just want to attempt to take this into account when making the recipe? It's not going to ferment a huge portion of the wort will it?

You are correct on the method of sour mashing: "I thought you just mashed like normal then added some grains in order to get some lacto in there, then after a couple of days (or however long it takes to get the sour you're looking for) proceding as normal." The definition of "proceeding as normal" is where things can go various different directions. Sour mashing with grain, I believe but may be wrong, generally leads to a heterofermentative fermentation thus creating ethanol in the process. It's this production of alcohol you want to take into account if you want to preserve most of it.

Heterofermentative strains have differing levels of attenuation and is also based on how long you let it go. I do not believe there is a concrete answer to this question - it's very strain and circumstance dependent since some strains can utilize homo- or heterofermentative pathways depending on various conditions that are present.

Pasteurizing after a souring period is pretty much a safe bet in any regard since you can kill the bacteria and preserve the alcohol. You would simply wait until your batch has reached the level of sourness you desire and then heat to ~165-190F for anywhere from 1-15 seconds (of course, sparging first if you're using sour mashing). I generally choose ~175F since pasteurization should be well completed by the time I get there. Then simply cool as normal and pitch your yeast(s).

 

[zmanzorro]

Pasteurizing after a souring period is pretty much a safe bet in any regard since you can kill the bacteria and preserve the alcohol. You would simply wait until your batch has reached the level of sourness you desire and then heat to ~165-190F for anywhere from 1-15 seconds (of course, sparging first if you're using sour mashing). I generally choose ~175F since pasteurization should be well completed by the time I get there. Then simply cool as normal and pitch your yeast(s).

When would you add hops in this scenario?

 

[NateLTB]

I just attempted my first sour mash and it's currently fermenting with S-05. I mashed in like regular and then after two hours I left the lid off (my mash tun is a 10 gallon Igloo cooler) and let the temperature drop to 105*. I then pitched a pound of un-milled grain along with a packet of GigaYeast's Fast Souring Lacto, blanketed the top of the mash with co2 and wrapped it in saran wrap. I checked the temperature every 12 hours and added hot water as needed making sure to re-blanket it with co2 after every hot water addition. I tasted the mash daily and after 72 hours it was nice and sour (and it smelled like sourdough bread baking). I mashed out like normal and did a short 15 minute boil with half an ounce of Tettnanger and some yeast nutrient. I tasted it after I mashed into my kettle and it was very tasty with a good amount of sourness. I then let it cool overnight (didn't want to run it through my plate chiller) split the batch into two five gallon carboys the next morning and pitched my S-05. Since the ph was pretty low it took about a day for the yeast to start kicking but it should be done fermenting in the next day or so. iijakii was 100% correct with his three tips and if you follow those you should come out with a nice sour beer.

 

[stpug]

When would you add hops in this scenario?

Depends on your goals, but some options are:
-during the decoction
-during the mash
-during the boil (assuming you boil prior to souring)
-during pasteurization
-hop tea is also a good possibility

But, keeping in mind the levels of IBUs that are detrimental to lactobacilli (specifically), you'll want to keep them low or make sure you get most IBUs after the souring process.

 

[signpost]

I did a sour mash Berliner Weisse that turned out pretty well. I took the more rustic/simple approach of pitching some uncrushed grain into the slightly cooled mash. Then let sit covered and in the garage for a couple days. It was in the summer, so I only had to add hour water once in order to keep it above 100°F.

After that, ran it off into the kettle, sparged as normal, and did a short boil (maybe 15 minutes) with just a little hop addition. Chilled and pitched done US-05.

It has just a bit of funkiness and plenty of sourness. My guess is pitching a pure strain of lacto from Wyeast, White Labs, or another company would give a cleaner sour. I personally enjoy the bit of funk I got in mine.

Although, as much as I like the end result, the mash itself was one of the most disgusting things I've ever smelled.