Sour mash/kettle souring - affordable setup?

Best approach is to mash in, complete your mash, sparge and bring up to 180*F to pasteurize, then cool to 100*F and pitch a Lacto strain that will work at lower temps (room temp) and let it ride until it hits the acidity pH you want. Then boil and chill for fermentation, pitch with yeast. I recommend Lacto plantarum as it works super fast (2-3 days) at room temp.

 

If you want to you can just mash in and leave it and you'll be fine. There's already lactobacillus delbrueckii on the grain. It'll smell really bad after a day or two, but it'll give you a nice, rounded sourness. Then just sparge and boil as usual, or if you want, and you've set up to get the gravity you need, you can simply skip the boil and just transfer it to the fermentor. It's a little known fact, but "white ales" used to be very popular in the United States - they were basically just a Berliner Weiss.

 

The issue with using the grains is that there are other bacteria that respond to oxygen and can still thrive at lower temps that will ruin your batch... been there, done that. With the easy access we have to pure cultures of Lacto today (Good Belly, yogurt, supplements, Omega & Giga yeasts, etc) there really isn't a reason to tempt fate using the random bacteria and yeast living on the grains.

 

I guess I live dangerously, because I sour using grain inoculation in a keg. But I also keep it at ~115F and purge the O2, so that reduces the risk of the wrong nasties taking over.

 

Of course, but that requires temp control and the ability to purge O2. A much easier and cheaper way is to use a different Lacto source that doesn't require either and get er dun in 2 days.

 

The anti-air recommendation for kettle souring is actually not for the benefit of the Lacto but for the nasty bacteria present on the grains that require oxygen to multiply and do their damage. Lacto doesn't care about oxygen one way or the other. It will work in the presence of O2 or absence, and the presence of it won't cause flavor issues. If you are using a pure culture like the pro-biotic pills and pasteurize the wort before pitching (to kill all bacteria from the grains still in the wort) then you should be fine. For piece of mind you can drop some saran wrap on top of the wort inside the kettle.

That said, my biggest concerns would be leaving the wort to sour in a kettle made of Aluminum as it is possible that there might be a reaction to the low pH? If your kettle is Stainless Steel you should be fine, or if you put it into a spare bucket. My other concern, and this is the biggest one for me, keeping freaking fruit flies out of the wort. As long as you can keep them buggers out of the wort while it sours it should all be fine. Although, the boil will kill them, and without any alcohol present they can't make acetic acid, I just hate the little critters.

 

Give this a quick read if you have some time:
http://www.milkthefunk.com/wiki/Lactobacillus

 

To a certain extent I'll agree with jbakajust1 on this as it's just easier buy something and pitch it - and it saves you time, and the smell of it - but I used to brew 542 gallons at a time and I never had a problem with any "other bacteria" getting involved. Another Philadelphia brewer did the same for his Berliner Weiss, and they constantly made that, it was like a "regular". And if you're going to mash-sour it, it will get covered in white mold.

As to procedure, I never used any form of temperature control but I was using a jacketed SS mash tun so it was insulated. However, later on at a different brewery we did the same thing in smaller batches (@ 15-20 gallons) to create a sour addition for our summer ale and we just did it in plastic storage bins. The lacto will get going and you shouldn't have to worry about temperature even if it's winter, the grain itself acts as insulation and it should hold some heat.

jbakajust1 does make an incredibly good point though, you shouldn't use an aluminum pot.

Good luck with it, and let us know how it turns out. And if things do somehow go wrong, remember that you can always just add fruit ;P

 

As a side note, most (if not all) the Oregon "kettle sours" are made by dumping Nancy's yogurt into the boil kettle and allowing it to sour for a few days.

 

I've been having fantastic luck with probiotics for souring. Ultimate Flora is the brand. 10 different lacto strains. Contents of 5 capsules into a 500ml starter for a few days. Then brew your beer as normal, rack to sanitized carboy when chilled to 70 ish F. Pitch probiotics first for 12 hours followed by your favorite saison strain/WL644/us05 or really whatever you like. Will only take 1-2 weeks to ferment out depending on your yeast strain and pitch count. Will have a very similar acidity to Anderson valley Gose. Oh other thing is keep your ibus below 5 or don't hop it at all.

I don't boil off the lacto. A solid cleaning regime will prevent your equipment from becoming infected unless your using a bucket or tubing with large scratches in them.

One pack of these pills is like 15$ but that's enough for 6 batches of sours so that's pretty damn cheap!!

 

Yes, cover it. No, you don't have to have an airlock, you can use foil like a yeast starter. I took a bar and new Apple juice, poured off a pint, and refilled with Good Belly and then put the cap on just leaving it a little loose. Still rocking. I put a paint strainer bag over all my starters to keep out any fruit flies.

 

When I brewed small batches I sour worted like this:

1. Mash like normal.
2. At end of mash add some acid malt to lower pH. Cool to 110-115.
3. Transfer wort into a big Ziploc bag, pitch raw grain or lacto vial. Get the air out of the bag.
4. Put the Ziploc into an ice chest and fill the ice chest with 110-115F water (easy if you have a tankless water heater).
5. Make sure the bag doesn't pop if you happen to have a hetero strain.
6. Refill water as needed in cooler and check sourness (mostly by smell for me) daily.

Have fun. This also works on 5 gallon batches but you need a big giant zip loc bag.

 

Just a thought...what kind of apple juice did you use? Does it contain preservatives? I don't know how sensitive Lacto would be to whatever preservatives your juice (may have) contained, but it did come to mind.