Czech Lager - The Bridge v2!

This is a repeat brew day. Exactly the same kit, the only difference is that I extended the primary fermentation time.

Notes

Brew Day

This time I’d get it right! I properly cleaned the fermenter, twice!

I’ve not got a lot of pictures from this brew day, it was really smooth again hot side. No issues at all.

My OG was 1.044. It finished a point drier this time at 1.006. Resulting in 5.1% ABV.

Fermentation graphs below have been smoothed - attached them via Brewfather too. OG was at 1.005 due to some trub on the pill seemingly.

This brew is still in progress.

Progress

After 12 days of fermentation, which is the recipe guideline, I tried the beer and there it was again: acetaldehyde.

It’s worth noting that I had ~3psi of pressure on the spunding valve as the ferment was finishing, just to prove I had no leak/oxidation risk. This has gone down very slowly but only due to absorbtion, I’ve kept it topped up but low to be absolutely sure zero oxygen contact.

I left it stable at 12c. The acetaldehyde was still there at 20 days.

As of writing this blog post, it’s been in primary for 30 days. Still lingering acetaldehyde. Today, I decided to rouse the yeast with CO2. Then it hit me, I realised what I’d done wrong on both of these batches. This is a lager yeast, it bottom ferments. I’ve had the yeast collection valve open on both of these ferments. The yeast cake has been trapped in a narrow collection vessel at the bottom of the tank meaning the majority of it has little/no contact with the wort. My problem has been stressed yeast/poor yeast health.

Maybe not conventional, but I lifted the fermenter up, released the full yeast cake back into the main vessel and then closed the valve, so that it would settle back down with more surface area and the yeast can do it’s thing. I had actually started the D rest but decided to drop back to 12c for a few days.

I hope it’ll turn around, I’ll keep tasting and see how it goes. I’ve not properly done the D rest yet. Fingers crossed.

The first batch keg is now drinkable, it’s mostly cleared itself up in the keg - it’s by no means perfect, but drinkable.

I don’t regret rushing into another batch, I enjoy the lager brew day/decotion process. Certainly learnt a lot to take forward on future batches, regardless of style. Anyway, I should end up with 2x19L kegs of Czech lager for the summer!