The second batch in my oak experimentation series was an English style brown porter. I again brewed ten gallons of wort and split the batch into two six gallon carboys. Each carboy received half of the washed yeast slurry from the UK IPA batch. After seven days of fermentation, I oaked one carboy with one ounce of medium toast American oak cubes and let the oak stay in contact with the beer for 27 days before kegging. The other carboy was oak free as a control.
The oak presence did not seem as strong as I would have expected. Trying both beers side by side, they seem like two completely different batches. For one, the non-oak version is much more clear than the oaked version. Surprisingly, the oaked version finished at 1.009 and the non-oaked version finished at 1.015. I don’t think it was an infection from the oak because I boiled the cubes in water before pitching them. That slight difference in finishing gravity gave the oaked version a drier finish and accentuates the roasted, bitter finish which borders on astringent. I think the oaked version would be better if it hadn’t finished so dry. There is a slight astringent, tannic flavor that is present in the oaked version as well as subtle notes of vanilla and campfire. The non-oaked porter seems more balanced and easier to drink because of the slight residual sweetness expected in a brown porter. This sweetness also allows the fruit and berry notes produced by the yeast to play a bigger role.
I feel like this was the correct oak choice (as opposed to French or Hungarian oak), but I would like to brew this again to see if the finishing gravity phenomenon happens again. If the oak somehow kick starts another fermentation and dries out the beer further (which I find hard to believe), I would bump up the crystal malts in the recipe to account for this or possibly mash a bit higher.
Both beers were delicious on their own, but I blended half of each batch into one keg and the results were amazing. So amazing that I served it at the Lagunitas Tap Takeover/Kyler’s Homebrew event at Brouwerij Lane a few weeks ago and it seemed to be the most popular of the three beers that I poured. So amazing that every time I try these beers side by side I end up dumping one glass into the other.
Brown Porter Size: 14.44 gal Efficiency: 82.0% Attenuation: 83.0% Original Gravity: 1.053 (1.040 – 1.052) Terminal Gravity: 1.009 (1.008 – 1.014) Color: 22.27 (20.0 – 30.0) Alcohol: 5.79% (4.0% – 5.4%) Bitterness: 28.8 (18.0 – 35.0) Ingredients: 13.75 lb (51.9%) Maris Otter – added during mash 6.0 lb (22.6%) Standard 2-Row – added during mash 2.0 lb (7.5%) White Wheat – added during mash 1.5 lb (5.7%) Brown Malt – added during mash 20 oz (4.7%) 2-Row Caramel Malt 80L – added during mash .75 lb (2.8%) 2-Row Caramel Malt 40L – added during mash 10 oz (2.4%) Pale Chocolate – added during mash 10 oz (2.4%) Chocolate Malt – added during mash 3.0 oz (67.8%) Fuggle (4.2%) – added during boil, boiled 60 m 12.0 g (9.6%) Warrior® (17.2%) – added during boil, boiled 60 m 1.0 oz (22.6%) Fuggle (4.2%) – added during boil, boiled 20.0 m .5 tsp Wyeast Nutrient – added during boil, boiled 15 m 1 ea Whirlfloc Tablets (Irish moss) – added during boil, boiled 15 m WYeast 1028 London Ale™ Slurry Notes Mash @ 152F for 60 mins. Did not wet grains prior to crushing, expecting efficiency drop London Ale repitch from UKIPA, one carboy will get oaked 10g chalk (mash) 2g gypsum, 7g CaCl mash pH 5.7 at room temp Chilled to 75 and put in fridge set at 65. Pitched yeast. No airlock until two days later. Raised temp to 70 after four days. Oaked one carboy w/ American medium toast oak cubes on 8/2/12 Kegged oaked batch on 8/29, oak isn’t too strong even after this long, 1.009, unoaked was 1.016?