Techbrau's sauergut method

[Techbrau]

I don't have pictures yet, but I will update this thread with some next time I make sauergut. For anybody who would rather make sauergut in small batches rather than maintain a reactor, I'll describe what I've been doing.

Instead of keeping a reactor going constantly, I have been doing the small batch method of making sauergut. I make 2 liters at a time using an Anova sous vide cooker. My method takes 3 days start to finish, but because I use a sealed sous vide bag you can keep the sauergut in the fridge until you need it after it's done souring. Making your sauergut culture on the same day that you get your yeast starter going isn't a bad idea, just think of it like a second starter.

If you're planning on brewing batches in quick succession, you can save some preboil wort and use it to make the sauergut for your next batch. Otherwise, I do a mini-mash using my sous vide cooker.

To make a sous vide wort, you can either use a mason jar or the vacuum seal sous vide bags. The idea is to basically do a no-sparge mini mash. Preboil and cool your water (a large electric kettle works great for this), add salts and SMB, mill your grain. Target 10-12 plato wort using a grist similar to whatever you're going to be brewing. Put the grain in the mason jar or sous vide bag, then slowly and gently pour the water in without splashing. If you're using a sous vide bag, you're not going to want to attempt to vacuum seal it when it's full of liquid. Just use a heat sealer (i.e. no vacuum), squeezing as much air out of the bag as you can before you seal it up. Put the mason jar or vacuum seal bag in your sous vide water bath, and give it a standard hochkurz mash including a good 10 minutes at 170 F to kill anything nasty. Cool it back down to whatever temperature your lacto culture likes (100-120 F depending on the strain)

Next, I gently decant the cooled wort into a second sous vide bag to get it away from the spent grain. I'm considering toying with the idea of using a hop sock in the mash bag, so that rather than decanting the liquid I can just open up the bag, pull out the husks, inoculate, then re-seal it.

If you're souring in a sous vide bag, you're going to want to use only homofermentative strains of lacto (e.g. L. Delbrueckii, L. Amylovorus, L. Acidophilus, etc.) and avoid heterofermentative strains that will produce CO2 (e.g. L. Brevis). For this method, it may be better to source a pure culture rather than throwing in a handful of malt. I've used WLP677 and it made good sauergut, but worked a little slowly. I bought some L. Acidophilus probiotic pills on Amazon that I'll be using next. I would recommend using a small amount of technical lactic acid when you inoculate to drop the wort pH down to below 4.5 just as safeguard against anything dangerous like C. Botulinum. It should take 1 ml or less for a 2 liter batch, but measure to be on the safe side.

Set the sous vide to your strain's preferred fermentation temperature, drop the sous vide bag of wort + lacto in, and come back in 3 days.

[Owenbräu]

Nice work! This seems very manageable.

[bjanat]

Nice, wish I had a sous vide cooker. White labs cultures are said to contaminated with yeast in many cases, though, although it might be better with purepitch packaging. I don't have access to it, but Goodbelly products are common in the US for this, according to milk the funk, shots or juice.


Sent from my iPhone using Tapatalk

[Bryan R]

Awesome work Tech, curious on your go with probiotics. L. Acidophilus is the main acid in my daily probiotics regimen as well.

[Owenbräu]

I'm also intrigued about the role of organic acids (and other various compounds) in sauergut and their affect on HSO in brewing. I just finished an experiment using ascorbic acid (AA) and it was very effective as an oxygen scavenger. My theory is that sauergut is loaded with these and other types of organic acids and buffering compounds (which is also consistent with the redox potential) and is effective in mitigating HSO during the mash and boil. I suspect there may be much more to sauergut than we think. It likely may serve for pH correction, flavor additions and HSO prevention. This story has just begun for us...

I suspect that if you use CA and AA to initially reduce the pH in your sauergut, then you can pre-load it with antioxidants and increase its effectiveness. But, that's another experiement for another time.

[Bryan R]

I don't think it's very "uncharted" Kunze speaks of oxygen reduction potential of SG. My SMB dose is 30mgl but I only use 10mgl of my sulfites from dough in to yeast pitch( this is with a 3hr cold trub separation process with multiple rackings ) since I started using SG. The beers are lighter in color, better in flavor, better fermentations, and clearer beer faster. Hell my mash times even went down because it activates the enzymes faster. It's a NOTABLE improvement across the whole process.

[Owenbräu]

That's why I stated "for us"

I stated in another thread that I need to read up on it more. I know Kunze speaks of the redox potential but I can't recall any work on oxygen scavenging. Is it still theoretical or empirically tested? Do we even know all of the constituent compounds in SG?

[bjanat]

[Bryan R]

I will be posting my SG reduction tests later today or tomorrow.

[Owenbräu]