Now that we had isolated our very own yeast strain, it was time to pray to the many gods of beer and hope that it would result in something drinkable. We wanted to use a fairly simple recipe to make sure the yeast would be the star player in terms of flavor. To determine the temperature that resulted in the best flavor profile (see ester post), the wort was split into three 1 gallon batches and placed under 3 different temperature regimes (Cold 45 °F, room temp 68 °F, warm 72 °F). The recipe is in the style of a Belgian pale ale and is as follows:
Fermentables
5.5 lb Light DME
.25 lb Caramel 40
.25 lb Caramunich
Hops
0.5 oz Galena 30 min
0.5 oz Hallertauer 15 min
.25 oz Chinook 5 min
Yeast
The Fringe
Estimated
OG: 1.050
FG: 1.018
ABV: 4.2%
IBU: 40
Starter:
A starter was made from the isolated yeast by going from a 100 ml starter to a 1 gal starter. The large starter was then allowed to ferment and settle. The liquid was decanted off until only approximately 2 L remained. I then swirled the solution to bring the yeast back into solution and filled 6 sanitized White Lab Vials. The remainder was then pitched into a 500 ml starter for this recipe.
Brew Day Notes:
The day went on without a hitch. Heated 4 gallons of water to 155 °F and steeped the grain for 30 minutes. The grain bag was then removed and the DME was then whisked in. The wort was then brought to a boil and the hops were added as is shows in the recipe. The wort was then cooled with the immersion chiller to 70 °F. The batch was poured into a bottling bucket for easy measuring and topped up to 3 gallons with filtered water. The batch was split between 3-1 gal jugs and 160ml of stater was added to each batch. The jugs were left at room temperature (68 °F) until fermentation had begun (about 12 hours). They were then placed at their respective temperatures (Warm, Room, and Cold temperatures).
It took approximately 2 weeks both the warm and room temperature batches to complete fermentation. The cold batch took about 3.5 weeks total. The vessel needed to be removed from the fridge for fermentation to begin again and then was placed back into the fridge. After fermentation seemed to slow the vessel was left at room temperature to finish fully and to clean up diacetyl.
Measured
Vol: 3 1-gal
OG: 1.051
FG: (Warm-1.018; Room-1.017; Cold-1.018)
ABV:4.3%
Tasting:
1-28-14:
Warm (72 °F): Pours copper with frothy white head. Aroma of clove, spices, slight fruit, slightly dry. Taste is slightly sweet up front with a bitter finish. Slightly tart. Very clean taste compared to the aroma. Light body.
Room (68 °F): Same appearance. Aroma of slight fruit otherwise clean. Taste is light grain, sweeter front than the warm with a slight bitter finish. No noticeable tartness. Light body.
Cold (45 °F): Same appearance. Aroma of light fruit, grain, Belgian spices, caramel, it is the sweetest of the three. Slight banana notes. bitter sweet finish. Light body.
Overall: This style and recipe was not exceptionally great, but we expected this one to be very mild in flavor because of the very simple light grain bill. The yeast strangely seems to be quite clean producing slight Belgian notes but otherwise no funk or noticeable off flavors. Amazingly this seems to be the case across the entire range of temperatures. The only real noticeable effect of the temperature was a longer fermentation (obviously) and the beer ended at a slightly higher FG and lead to a slightly sweeter beer overall at cool fermentation temperatures. This was quite surprising to us to have a first attempt wild yeast that both attenuated relatively well (64%) at all three temperatures and did not impart any crazy off flavors. It would be interesting to pitch this yeast into a more complex Belgian style where the grain bill is more complex, like a Dubbel or a Quad, especially to see how it handles the higher levels of alcohol.
Currently, the yeast is being worked up in the lab to determine what genus and hopefully species it is so that we can better characterize it. Updates will follow!
