Kolsch Brewday Report

[caedus]

I made a planning post for a Helles Recipe on the reddit.com/r/lagerbrewing sub, but have been craving Kolsch, and wanted to give my new system a test batch before jumping into the Helles.

The System

I built a mash tun, after getting frustrated with the limitations of my BIAB system and my old cooler mash tun.

It features the standard output ball valve, with an inlet about 8 inches above it for recirculating the mash. I use a domed false bottom, because I didn't feel like paying for a custom one, and I use the canning rack that came with the kettle on above it. I doubt I need it, but I was worried about mash scorching with directly heating the tun. I realize now that it probably isn't needed.

The mash tun has a silicon "gasket" I made around the lid to prevent air from being transferred too much. I plan on running more tests, and the hope is to have a mash tun where I can fill, purge with CO2, and then "seal" it with a one way valve.

Boil kettle is nothing elaborate, just an aluminum kettle with a ball valve, and I will be adding a whirlpool arm.

The Recipe

Gewinner Kolsch

85% Pils (Weyermann)

12% Pale Wheat (Weyermann)

3% Carahell Malt (Weyermann)

13 IBU Tettnanger (1 oz, 3.9AA) @ FWH

11 IBU Tettnanger (1 oz, 3.9 AA) @ 30 minutes

2L Starter of WLP 029 Kolsch

The Process

So I filled my boil kettle with 9 gallons of water, boil it, chill it partially, add SMB, then transfer into the mash tun with the grain already in there. Checked my temp, and adjusted it accordingly to hit my standard Hochkurz temps.

I was getting nervous, as it seemed like conversion was taking forever. Usually by the time I raise to the second step I am ~60% done with conversion. This brewday I was at 1.020 by the time I raised temps. I ended up stirring the mash once, just to break up the grain that was so tightly clumped together.

Transferred to Boil Kettle again with First Wort Hops already in there. Raised heat and began to boil. Never in my 2.5 years and ~60 batches have I seen such a gnarly looking boil. I understand now why the Germans refer to it as "Breaking the Boil". Huge chunks of nasty looking protein scum made a film, which I scraped off as best I could without scooping out hops.

Boil went as expected, went on to chill using my new SS immersion chiller. I don't like immersion chillers much. Bulky, and the weight of the hoses made it bend and awkward to work with.

Into the fermenter, pitch yeast. Wait an hour to oxygenate, then oxygenate a second time after another hour.

The Results

Mash out DO : 0.84 PPM (sample taken from the boil Kettle after transfer).

Pre-pitch DO : 0.64 (sample taken from carboy)

Efficiency : 70%

The Takeaway

1. Get some fucking quick disconnects. Bargain fittings is where I went to purchase camlocks. I have no doubt that the splashing and the extra work led to more O2 uptake.

2. Ditch the unnecessary mash equipment. I will just use the false bottom. I don't think scorching will be an issue with the near constant recirc.

3. Build a water proof switch setup for the pump. This was a Frankenstein brew day, so I just manually plugged it in, away from the brew. I love the pump though, so much cleaner and easier.

4. Get pre-chiller set up. The groundwater was 70 degrees, and still took a while to get down to temp. My counterflow chiller has spoiled me.

5. Get a second burner. Right now I only use one, and I have been satisfied with that, but I think using my smaller burner during the mash to keep temps will prove to be much better.

Bonus :

Gallery of the brew day

[caedus]

I should add:

I tasted the characteristic commonly found in German Lagers, the grainy-sweet aroma and flavor. It was awesome. The mash was far less effervescent than usual, as per your guys' predictions. I look forward to brewing more with this. Next brew planned in an Altbier. Anyone done LODO with darker styles?

[Brew4Fun]

Looks like a definite step in the right direction. Nice photos, thanks for sharing. Maybe one day I'll have a DO meter to play with (jealous!).

In regards to purging headspace with CO2: With cold/room temp liquids is futile because the CO2 absorbs so quickly into solution that more gas is needed, quite frequently, in order to keep headspaces purged. I've used co2 for purging headspaces many times and am always amazed at how quickly I see suction on airlocks afterwards. I took a couple times before I realized what was going on (i.e. co2 going into solution). I suspect that nitrogen or argon are better options here since they are less "dissolvable" into liquid solutions.

[caedus]

I might be able to find some argon... Thanks for the heads up on the solubility of CO2.

I think I am going to jump in and shoot for the Helles Next. I will take better notes this time, too, now that I am a bit more adjusted to how the brew day will go down.

[Kit_B]

Nice!
The lighter color is something we all experienced & were shocked by.
Incidently, this allows you to load up on cara malts, if you need/want to.

[Owenbräu]

Yeah, I've brewed lodo altbier. Great work today, btw.

[Bryan R]

I have done dunkel and so has Wobdee and Brandon has done the ski beer.

[bensonledbetter]

Great write up! Any issues with the aluminum kettle? I learned today that the office layer that aluminum forms is a no no for low DO brewing.

[Techbrau]

The oxide layer on aluminum should be stable down to a pH of about 4.5. So it's cutting it a bit close but I am thinking aluminum may not be a problem.

[caedus]

From what I understand the aluminium oxide layer is quite stable. I was under the impression that it starts to break down at 3.5 pH, having no formal chemistry education, I will let that become a topic discussed by smarter minds than mine.

I would like to invest in a stainless kettle, but I can't justify the extra 100 or so dollars to build one myself, yet without data to back up aluminium and its affect on lodo.