German Brewing

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This, folks, is my low oxygen brewhouse. I'm mildly embarrassed to show it, but it demonstrates how easy it is to get into low oxygen brewing, once you understand the concepts.

Brewday outline

Boil entire volume of water in the kettle

While the water is heating, I weigh out and condition the grain with 2% water by weight ie 4.5kg=90g

After the water has boiled for at least 5 minutes, I start chilling. I still use a... wait for it... copper immersion chiller . Add 100mg/L sulfite when it's below 80c and stir gently. Let chill to strike temp

Mill the grain directly into the empty lauter tun (cooler.) I then blow a little co2 into the cooler through the drain valve to hopefully flush some o2 out

Set the cooler on the ground and hook up the silicone hose. Fill the tun slowly from the bottom, stir VERY gently, but enough to thoroughly mix and hydrate grain

This part sucks. Lift the cooler up onto the sawhorses

Note - I've performed step mashes in two different ways. The first is to mash in with around 3L/kg, boil the remaining water in the kettle, and add infusions with a pitcher to hit the steps. The second is to mash in with the full volume, then lauter at the end of the first rest. The wort only is then heated through the remainder of the steps while in the kettle. I haven't decided which way I like better, yet...

When mash is done, runoff a pitcher's worth of wort via the hose to flush out any grain particles, then very gently add back to the top of the mash. Hook up hose to boil kettle and run off the wort

First wort hops are sitting in the kettle to meet the wort. I start the burner, but keep the temperature below 80c for at least 45 minutes

Boil the wort. I partially cover the kettle to keep the boiloff rate under control. I'm usually at 98c and 10% evaporation for a 60 minute boil

Chill with the immersion chiller. I stir gently, but pretty frequently. I can usually have the wort down to 15c in about 15-20 minutes. Runoff via the pickup tube

Honestly, I think this is a fantastic way to go! I always say I thought my old cooler mash tun used to make me the best beers. It's when I scaled up and had to add pumps and such that things got complicated. Becoming conscious of aeration, heat and sheering stresses dialing everything in now I have easy precision control, can scale, and don't have to lift anything (for what all that is worth).

That is the sole reason I dislike my current setup - lifting. I need to either setup a HLT at a height above the mash tun, or just get a pump. Lifting a full volume no sparge sucks

PART 2: FERMENTATION

Currently being used to bottle/keg condition weissbier, but you get the drift

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Fermentation chamber is an old refrigerator with an STC1000 controller and a hair dryer heat source. High tech, I know...

Cooled wort is sitting in the kettle

I use kegs with shortened dip tubes for fermenters

Yeast pitch goes in the keg first, then the wort is runoff via the hose to the bottom, so there's no splashing

The wort is at 15c or so upon pitching, but immediately goes in the fermentation chamber set at pitching temperature. It will cool down within a few hours, before the yeast is active enough to cause any ill effects. I'd rather do this than wait and risk the wort oxidizing without yeast

A blowoff tube is hooked up to the gas fitting of the keg

A couple hours after pitching, once the wort is chilled to pitching temp, I'll hook up the aquarium pump (with filter) to the beer tube of the keg. It would be better to have an aeration stone on the end, but this has worked well enough that I haven't bothered with it

I'll run the pump for a few minutes, until foam starts to come out the blowoff tube. Stop, come back later and do it again. I keep repeating this process every few hours until the fermentation is releasing co2 - usually within 12-24 hours

Once blowoff is finished and the fermentation starts slowing down, I swap the blowoff hose for a spunding valve set to low pressure, 3-4 psi. Just enough to push samples out a picnic tap

When the gravity is 1.5p above the expected final gravity, I transfer to a purged keg via gravity siphon and jumper hoses

Harvest yeast cake from primary keg

Spunding valve goes on secondary keg, set to full carbonation pressure

Eventually this keg gets moved to the kegerator for lagering, and then serving from the same keg. I no longer filter or transfer to a serving keg. Clear beer two weeks faster isn't worth the risk of picking up oxygen during the transfer, and losing "it"

I have 3 questions so far:

1.) Have you measured DO or sulfite concentration to estimate uptake?
2.) Your slow(er) chill intrigues me. Primarily because I'd rather not buy a second SS chiller, either to use as an IC in my 5G BIAB or as a pre-chiller to the plate for our 1/2 bbl.
3.) Speaking of chillers...did you say a copper IC?!

Asking purely because a lot of this resembles my smaller system, which is way easier for me to brew on more often..

I am by no means the example one should follow, and some of the other guys are way ahead of me in equipment and process. If you can't tell, I'm cheap.

However, the takeaway is that my system is far from perfect, but doing the best I can with what I've got is STILL night and day between pre- and post- low o2.

Copper is bad. People should be discouraged from using it anywhere it touches the wort, but, you can overcome a lot of less than ideal things when you have an active chemical scavenger at work. I rinse my chiller with star san each time before dunking it in water, in the hopes that the acid is removing some of the oxide layer.

Also, as I mentioned, I'm cheap, so I don't have a DO meter yet. I have some sulfite test strips to estimate how much is being consumed, but haven't had a chance to use them much yet.

Good work, Steve. Honestly, pumping is the easiest way to introduce oxygen and best way to ensure the most surface area gets exposed to air. I would bet a static vessel is the easiest way to preserve fresh, lingering malt flavors. I went full tri-clove (1.5", not the 1/2") because those provide the most surface area of gasket seals of any quick disconnect out there. Some call it overkill; I call it insurance.