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The research brewery at Weihensttephan Institute |
Now you may have heard it said that this yeast is a "hybrid yeast". And you may be thinking it is a "hybrid" in the slang sense of the word, like a San Francisco lager yeast. Or like a "cream ale yeast." I want to assure you this is a strain of Saccharomyces Pastoranus, one of the two most prevalent strains of lager yeast. It is a hybrid only in the fact that it is hybridized from Saccharomyces carlsbergenis. We have to be careful with the word hybrid when we are talking about genetics. Genetically if something is a hybrid, it doesn't exist in nature. Of course if you want to get truly technical, all lager yeasts are hybrids.... but that is a topic for another blog entry. It was developed at the Weihenstephan Institue. But it isn't just a combination of S. Carlsbergenis and S. Cerevisiae; it is an actual lager strain, most commonly classified as a S. Pastoranus.
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Genome map of 34/70 and Saccchoromyces Pastoranus vs. S. Carlsbergenis |
Understanding yeast genetics and yeast genomes is not necessary to brew great beer. But it can be interesting. If you ever want to really geek out go to the TUMs website. There is so much information there, I think even the geekiest of home brewers would learn something new. The 34/70 strain does exceptionally well from 48.5 F to 71 F. Average attenuation is about 83%, in an 18 plato (1.064) wort. Marshal, over at Brulosophy reports great results up to 70 F with this yeast. I am not that brave. But I have used it for years at 62 to 65 F (16 to 18 C) with excellent results. I know this is just a blog on the internet. I know I am not a brewing scientist (wish I'd known that was a choice on junior high career day). I am just a guy sharing practical experience with you. So please do your own research and remember my 45% 45% 10% rule. Great brewing is 45% cleaning, 45% learning, 10 % brewing. But I will tell you this, I have done the research. I have read the articles and even struggled through the research studies. The knowledge I have gleaned is that this yeast will work fine at ale temperatures.
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Knowledge is power! |
So here is the recipe. Good ol' Merican Pilsner... 5.5 gallons of good "merican" beer. 72.5% efficiency. So adjust yours for your system. Remember we tend to not sparge this beer. I have never decocted this recipe, but I am considering it. To do that I'll dough in for a 132 initial rest / enzyme wash. When I dough in it will only be the barley. Then I'll pull a 2/3rds decoction. After I add back the decoction, I'll add the corn and rice for the remainder of the mash. But as you all know I enjoy decoction. It is not necessary, I just want to see what it would do to this recipe.

1.047 OG
1.007 FG
12.00 IBUs
3.00 SRM
4.8% ABV
Grain Bill - Mash at 148 for 60 minutes, rinse or sparge to volume.
7 lbs of Pilsner
1 lbs of flaked corn
1 lbs of flaked rice
Hops
.2 oz of Magnum 13% AA - 2.6 AAUs - at 60 minutes
.2 oz of Liberty 4% AA - .8 AAUs at 30 minutes
.5 oz of Liberty 4% AA - 2 AAUs at 0 minutes
Yeast
17 grams of Fermentis Saflager 34/70 - (that is 1 & 2/3 packs) Ferment at 62 for 5-7 days, then let rise to 70 for 2-3 days, then cold crash. Or make a starter, if you start with 1 pack of 34/70 then you only have to do a single step to get to 345 B Cells. Make sure you oxygenate well.
Extras
1 Whirlflock tablet
1 tsp of Wyeast yeast nutrient.
What's that? you say you don't like 12 IBU beers... fine... turn it into a Pivo Pilsner Clone... If you have never had Pivo Pilsner it is a 59 IBU pilsner beer made by Firestone Walker brewing. It is made to honor the classic Czech Pivo. But really it is more like an India Pale Lager to me. Either way it is delicious. This grain bill stands strong as a great back ground for many of your lager experiments.
A laundry tub and some frozen bottles of ice are all you need to make this fantastic lager. Anyone can do it. |
Pivo Pilsner Clone 145 calories
1.047 OG
1.007 FG
53.00 IBUs
3.00 SRM
4.8% ABV
Grain Bill - Mash at 148 for 60 minutes, rinse or sparge to volume.
7 lbs of Pilsner
1 lbs of flaked corn
1 lbs of flaked rice
Hops
1 oz of Magnum 13% AA - 13 AAUs - at First Wort Hop
1 oz of Spalt Select 5% AA - 5 AAUs at 10 minutes
1 oz of Spalt Select 5% AA - 5 AAUs at 5 minutes
2 oz of Saphir 3.4% AA - 6.8 AAUs 5 day dry hop
Yeast
17 grams of Fermentis Saflager 34/70 (that is 1 & 2/3 packs)- Ferment at 62 for 5-7 days, then let rise to 70 for 2-3 days, then cold crash. Or make a starter, if you start with 1 pack of 34/70 then you only have to do a single step to get to 345 B Cells. Make sure you oxygenate well.
Extras
1 Whirlflock tablet
1 tsp of Wyeast yeast nutrient.