It has been known for some time that lager yeast, i.e. Saccharomyces pastorianus, is a hybrid of Saccharomyces cerevisiae (ale yeast) and another ‘lager species’ of Saccharomyces. Libkind et al. (2011) recently discovered a new species of Saccharomyces, named Saccharomyces eubayanus, in the forests of Patagonia, and since it genetically matches the non-cerevisiae part of the pastorianus-genome, it now appears as if the ‘other parent’ has been found. Lager yeast is known for its capability of fermenting at low temperatures, and it is believed that this trait has been inherited from S. eubayanus. Because of the recent discovery, there hasn’t been much research on S. eubayanus yet, but I thought I’d try to brew a small test batch with the yeast this weekend on my old brewing equipment. I’m not really sure what kind of flavor profile to expect from S. eubayanus, but I’m assuming it will be quite estery and ‘non-clean’. The malt bill will be simple, featuring 80% Pale Ale malt, 10% Munich malt, 5% Crystal and 5% wheat, and I will aim for an OG around 1.050. I plan on mashing quite low, since from experience with experimental fermentations in the lab, S. eubayanus ferments quite slowly and attenuates relatively poorly. I will be aiming for about 30 IBU, and will hop with something I have available in the freezer, i.e. most likely Simcoe (since I have some 2011 harvest leaf hops I want to use up). I plan on fermenting at 12° C, as I want to minimize any potential esters and funky flavors.
Recipe: Eubayanus Blond Style: Blonde Ale TYPE: All Grain Recipe Specifications -------------------------- Boil Size: 19.68 l Post Boil Volume: 17.68 l Batch Size (fermenter): 13.00 l Bottling Volume: 11.00 l Estimated OG: 1.049 SG Estimated Color: 15.6 EBC Estimated IBU: 29.9 IBUs Brewhouse Efficiency: 60.00 % Boil Time: 60 Minutes Ingredients: ------------ Amt Name Type # %/IBU 2.800 kg Pale Ale (2-row) (6.0 EBC) Grain 1 80.0 % 0.350 kg Munich (20.0 EBC) Grain 2 10.0 % 0.175 kg Crystal Malt - 60L (Thomas Fawcett) (118 Grain 3 5.0 % 0.175 kg Wheat (6.0 EBC) Grain 4 5.0 % 8.00 g Simcoe [13.00 %] - Boil 60.0 min Hop 5 15.0 IBUs 16.00 g Simcoe [13.00 %] - Boil 15.0 min Hop 6 14.9 IBUs 16.00 g Simcoe [13.00 %] - Aroma Steep 15.0 min Hop 7 0.0 IBUs 1.0 pkg Saccharomyces eubayanus [124.21 ml] [Add Yeast 8 -