Czech Premium Pale Lager 2019

>> Sunday, July 07, 2019

Today I'm brewing a Czech Premium Pale Lager. I've brewed this beer three times now, with somewhat mixed results. The first time I brewed it, it won gold in competition. The next time, it got a brett infection from my counter-pressure bottle filler (the reason why I now always pasteurize the bottle filler before and after using). The third attempt had an acetaldehyde issue, a problem I had on a couple beers I was trying to rush to get ready for competition last year. For this beer, I'm hoping for a return to the gold medal example.

I'm changing the recipe slightly, using a different base malt and different yeast this time. I always like to experiment with new I'm ingredients, so that's the reason for changing up the malt.  Yeast-wise,  I want to try out 2124 in a few beers, so I'm hoping to reuse the yeast cake. I'm also doing a little experimenting based on comments in a recent Brewing Network podcast.

In S1 E12 of Hop and Brew School from The Brewing Network, Nick mentions using a small amount of Branched Chain Amino Acids (BCAA) as a yeast supplement to reduce the chance of diacetyl in finished beer. The only problem is he didn't provide much info with respect to usage/dosage. I sent a question to The BN on this subject, but it will likely be a while before their next Q&A show. I also posted a question about this subject on Reddit, and I was directed to a research paper titled, Influence of valine and other amino acids on total diacetyl and 2,3-pentanedione levels during fermentation of brewer’s wort.

Assuming I'm interpreting the findings correctly from this paper, supplementing between 100-300mg Valine per liter of wort, can reduce the overall amount of diacetyl produced, and seemingly increase the uptake of diacetyl at the end of fermentation. In my layman's interpretation, it basically means extra insurance against diacetyl issues and it could shorten the turnaround time when brewing lagers.

I went ahead and ordered some unflavored BCAA 2:1:1 from MyProtien and I'm going to try using it in this recipe. I'm planning on shooting for the low end of the 100-300mg/l dosage. Per the nutrition label on my package, each 7g of BCAA 2:1:1 contains:

  • 2.5g Leucine
  • 1.25g Isoleucine
  • 1.25g Valine
  • 2g Carbohydrates
That means at a dosage rate of 560mg/l BCAA, we're getting 200mg Leucine, 100mg Isoleucine, 100mg Valine, and 160mg Carbohydrates. A 5 gallon batch is ~19l, so 19*560 = 10640mg/5 gallons or 10.64g/5 gallons of BCAA would be the proper dosage to yield 100mg/l Valine. I could only find one other reference of a Homebrewer using BCAA, and that was with gluten-free brewing. The dosage rate mentioned was 0.5 tablespoon per 5 gallons. I weighed 0.5T and it came out to 4.66g. I decided it would be better to be a little low than too high, so on this first round, I'm going with 1T (9.32g).

If you're brewing a Czech Lager, you definitely want soft water. If you're in the same situation as me and your tap water is hard, plan on getting some distilled or RO water Here's the recipe as I'm making it today:

5 Gallons

8.0# 11 oz. Weyermann Barke Pilsner
9 oz Briess Carapils
1.0g BrewTan B in mash
34g Czech Saaz (60 min)
41g Czech Saaz (30 min)
20.5g Czech Saaz (10 min)
20.5g Czech Saaz (0 min)
Wyeast 2124
Wyeast Nutrient (5 min)
9.32g BCAA (5 min)

Mash at 154F. Start fermentation at 45F, ramping temps up to ~50F over 5 days. Start diacetyl rest when gravity is down to around 1.020. For the d-rest, I tend to bump it up a couple of degrees morning and night until I got about 65F. I leave it there for a couple of days before I start cold crashing.

Water Recipe
10 gallons distilled water
0.55g Epsom Salt
0.33g Calcium Chloride
0.44g Baking Soda
0.44g Chalk

Brewing Notes
No major issues. I was also kegging my latest batch of NZ Pilsner and had a very minor boil-over while attending to that. I would guesstimate I lost about 6-12 ounces of wort. I was only able to chill down to 70F, so it'll have to chill a while before I pitch the yeast. Gravity measured 1.055 per the Tilt.

Update 7/9/2019
I aerated and pitched the yeast last night. I also finally got logging working on my Tilt Hydrometer. I'm not sure exactly what the problem was, but I could never get it to write to the Google Sheets when I was hosting it on my own Google account. I ended up doing a couple things. First, I did some tweaks on my Nexus 6P to enable Always On Display and prevent it from going into sleep mode when charging. Then I upgraded to the Tilt 2 app, and now I'm successfully logging to the cloud using the default logging option. It'll be nice to be able to check gravity and temp from anywhere, especially with lagers and timing the diacetyl rest.

Update 7/10/2019 AM
I'm starting to get a little worried, I haven't seen any change to gravity yet and no signs obvious signs of fermentation. I'm crossing my fingers that we see something tonight.

Update 7/10/2019 PM
When I got home from work tonight, I was finally seeing signs of fermentation.

This is pure speculation, but I'm wondering if the higher concentration of amino acids could have contributed to an increase in the lag time as the yeast were trying to absorb all of the available nutrients. It would be impossible to confirm that at home without access to specialized equipment. About the only option I have is to repeat the conditions as closely as possible on another batch, and see if I experience similar results.

Update 7/12/2019
Gravity is down to 1.041 this morning.

Update 7/16/2019
Gravity was down to 1.020 yesterday, so I started ramping the temps up. Gravity is down to 1.014 today.

Update 7/27/2019
This beer went into a keg today along with gelatin for fining. The gravity finished at about 1.007, putting the ABV at 6.3%.