Sour Mash Advice

I sour mashed 100% of a berliner wiesse for 5 days at room temp. It was too long and left a nasty aroma. I would advise using an air lock to keep oxygen from the part you are souring and only souring 3 days. It might also help that you are only souring 20-30%.

 

Flush your mash tun with co2 and dont over aerate the mash while stirring. I've had good luck mashing as normal then gently mixing in a pound of unmashed grain in a co2 flushed cooler. waited over night then boiled, hopped, cooled, pitched etc.

I've done the same without flushing and it turned into a vomity mess.

 

I commonly do a 3 day sour mash that ends up with a very clean lactic bite.

I keep everything in my cooler mash tun, after temps drop to 110F I mix in a few handfuls of grain stir, and then flush with CO2 to create an anerobic environment. I then cover the top with saran wrap and seal the lid. In summer time I leave the mash tun outside for 3 days to maintain temps above 90F.

After 3 days I drain, no sparge, and then boil and hop as usual. So far I have had great success with this method and my wife has made award winning Berliner Weisses using the same technique.

The key is to make sure there is as little oxygen as possible, you want nothing that will lead to butyric acid production in the mash as that will ruin a beer.

 

I do sour 100% of my mash for 3 days. I do not feel like i get an overpowering sourness from it. In terms of no sparging. I do intentionally use about 50% more grain (a stronger mash) than I normally would to compensate for the lack of sparge. I then will dilute the 1st runnings in the boil kettle to hit my target pre-boil gravity. With this method my volume isn't always spot on but I'm not as concerned with volume as much as I am with gravity and flavor.

I read somewhere you shouldn't sparge a sour mash. I can't remember the exact reason why but they had one. I've never sparged one and all ten or so that I've done have turned out perfectly.

 

I just started kegging and thus have a new CO2 tank. How does one go about flushing the MLT with it? I have a 10-gallon Rubbermaid.

 

If you want anything near a sour beer, you need to sour 100% of the mash. Even then, you will typically only produce a beer that could really be described as "tart".

Oxygen is your absolute biggest enemy with sour mashing. At home, I like to sour mash in a corny keg that I purge prior to mashing in and then keep it under CO2 pressure for the duration of the sour mash. Using this technique, you can easily mash for a week with no off aromas. But the pH typically levels off at around 3.7 by day 3. On brew day, just dump the mash back into your usual MLT, and brew as normal.

If you are diligent about oxygen control, your mash will never take on any off aromas at all, it will just smell like dough/bread with a slight sour twang. If you don't control oxygen, you can get garbage aromas, pukey aromas, poopy aromas, all sorts of nastiness. And if you smell it in the mash, you will be able to taste it in the mash, and if you don't have a good long hard boil, and a good rapid fermentation, you will taste it in the final beer. Even with those things you will probably get some subtle nastiness in the final product.

 

These are great pointers, as I've been thinking about trying a sour mash. My hesitation comes from not wanting to ruin a whole batch. So, a few questions.
1) to restate the "flush with CO2" question: ideas on how to do this? I have a CO2 tank b/c I keg. My guess is I detach the keg attachment quick release and slowly open the bottle with the hose pointing in the cooler.
2) the guy at my LHBS said to do a "mini sour mash". Make a mash w/ 1/3 or 1/2 the grains. When the temp falls to 120 deg toss in a handful or two of grain. Let it sit for 2 days. Then brew as i usually would with the rest of the grains. I drain the liquid off the sour mash by pouring it through a strainer.
3) I like the mash in a corny keg idea, but is it big enough? Can I reuse it or once it's used for sour, it's only for sour?
4) How do you keep the temp up? I was told to pitch the extra grain at 120 deg b/c at that temp the bad bugs are killed and the good things live. Below that and the bad bugs live. But it shouldn't go below 100. I'm thinking a sleeping bag and heating pad, but wondered what you use.
Thanks.

 

Glad to see Kennedy chime in with his experience.
I did an article on sour mashing a while back and all my sour mashes were partial mashes, I think I did up to 30% or so, doing beers like a dry stout, a summer wheat & berliner. None came out truly sour, but the only one I was really going for that with was the berliner. My buddy did the full mash souring and the beer ended up being a dumper...mainly because he just put the lid on his mash tun with pretty much no O2 control. My mashes were done in erlenmeyer flasks that I could mash & keep in the flask without any movement or way to introduce O2, then topped off & sealed with wrap. I could then even bring temp of mash up to boil to drive off as much 02 as possible (maybe overkill). Kept them very clean.

1)Yes, let it flow for 15 seconds or so.
2)Your call there, sounds like the most up-to-date from experienced sour mashers would be found on this thread
3)You should be able to get upwards of ~12lbs of grist with strike water @1.25qts/# in a 5gal vessel. If you're looking for an 11gal batch size, then probably not, but for a 5gal flemish red with moderate abv, that should be more than enough. Yes, just clean with PBW/oxyclean soak & then hit with star san and it will be good to go.
4)I had a boiler closet that worked great during the winter. Not sure if you have a "hot space" but just try to keep temp up. If you do everything correct controlling O2, your mash should turn out fine whether you're at 90 or 110F.

 

I guess tagging on to this thread is as good a place as any.. hopefully it won't just get lost in the mass.
I'm in the midst of my first attempt at a sour mash, and I'm finding mixed information on the free internet sources I can get to. I'm also a biochemist, so I'm interested in what's really going on and really understanding how to optimize and select for what I want.

So without further ado- I'm working from a byo.com recipe for a farmhouse saison summer ale clone (flying fish brewery) clone. It gives super simple instruction: mash 3 oz 2-row pale malt at 150 deg F, cover, let sit 2-3 days. ha! well I did just that, but then I went reading. Well I lied, I always tweak, and decided I want more sour, so I did 1 lb of 2-row. Their recipe said 1 pint water. I have a growler around, so I did mine in that. I started with about 2 pints of water. Then I got to reading about how anaerobic is the way to go. Lots of people recommending CO2 flushing. That's tough for me to come by, so I decided instead to just top up the growler right to the rim with more hot (150 F) water. I sealed it tight. I put this growler in a big cooler, and I added hot water from time to time. I probably kept it 110 deg or so for the rest of that evening, and then it cooled down close to room temp over the course of that night.

Next morning I check it- 1) definitely producing gas- lots of pressure built up. I loosened the cap and let it go, seemingly a large volume of liquid was released. 2) smell was a little off, but not what I'd describe as terrible.


so I did more reading and now I'll start in on some questions.

My understanding is I want L. delbrueckii, and it's naturally in the husks. the goal of the hot ferment is that this bug will outlive the others, coupled with minimizing oxygen to prevent the acetobacters and such of the world getting involved.

I'm told to watch out for butyric acid- the smell of sweat/vomit. I'm sure that this is a component of what I smell, but compared to what I'm reading, I'm not sure if I'm worried. It's there, but I'm not gagging. So-- is it possible I have a mix of the delbrueckii and another guy?

on wikipedia butyric acid page, I'm told there's a few bacteria that can be responsible: clostridium butyricum, clostridium kluyveri, clostridium pasteurianum, fusobacterium nucleatum, butyrivibrio fibrisolvens, eubacterium limosum. a couple of those have their own wiki pages. to comfort me a little, at least one of them is actually included as probiotic in Japan- and then there are whole webpages out there talking about butyric acid being good for your gut (when produced by the neighboring colonic flora at least). That part is beside the point.

I learned a couple things: in the butyric acid production pathway, CO2 and elemental H2 gases are formed. in homolactic fermentation as delbrueckii should be doing, there should be no gassing. There are a number of guides I'm seeing out there telling one to totally seal the vessel, and to me this sounds like a bad plan with knowledge you might end up with another bug making gas. anyway H2 gas, that's neat--- since that's lighter than air, I imagine I could hold a match a couple inches above my vessel and prove it's H2 coming off... And the CO2 should actually make for a buffer in a way, so the H2 will just burn off and be gone.

anyway, on to at least one point/question: I don't see any real details about the temperature differences responsible for selecting a delbrueckii from a c. butyricum, etc. Both are anaerobic bacteria, both obviously live well at low pH, it's just a matter of getting lucky? Thinking I might have actually done more harm by heating all of my grain to 150 (according to that byo recipe), I tossed a bit more fresh grain in the same vessel last night. I also took a taste of the grain itself. As I said, while I do smell off-aroma, the taste is definitely soured already, but actually pretty clean. so there can't be that *much* butyric acid yes? if anyone actually has good information on the ranges of bacteria these bugs live at (both lacto and the butyricums of the world) I'd be interested to see.

now another question, somewhat related: I make sauerkraut, and that's dead easy. The right lactobacillus is present to start with, and provided there's some salt around, it's sealed off from air, it has always worked for me. I would kind of presume that in that case, there's just more of that lactobacillus naturally present on cabbage than there is delbrueckii on my malted grain. Even so-- the goal here is lactic acid- what if I took a small amount of my sauerkraut and tossed it in for my sour mash? I'm not sure exactly what lacto is responsible there- I'm sure it'd make lactic acid- but would it produce some other off flavors I'm not thinking of? would be a fun experiment... and the influence of the sauerkraut itself should be pretty negligible as I'd only use a small amount and could remove the sauerkraut prior to actual mashing.

As you might be able to see, a lot of this is just my curiosity. For now, I'm planning to keep my sour mash warm by putting hot water in the cooler from time to time, until Saturday, which will be 3 days souring. I'll smell it some more, taste it again, and make a game time decision on whether to put it in with my regular mash (extract brewer by the way.. and if I decide to toss the sour mash, I'm still gonna make a pretty good beer). I'm assuming if the flavor itself isn't bad, then it's unlikely to ruin the beer. it's ultimately a fairly small component over all.

but if anyone wants to chime in with advice on this particular mash prior to saturday I'm all ears.

Thanks to all who read and comment!

 

I did a post on the science as I understand it yesterday. Here's the link…

http://www.homebrewtalk.com/f36/hopping-sour-mashed-beers-440275/

 

@ChrisKennedy I love the corny sour mash idea. Would you dedicate a corny to sour mashing if you only had 1 or 2 kegs or would a heat cleaning/pbw soak make the corny good to go on the next microbe free beer?