Dry stout is one of my favourite beer styles (try the Deèsse Nocturne at DDC if you want a great example) but I’ve been reluctant to brew one at home. However, a recent beer trick I’ve discovered has changed my mind.
The definitive dry irish stout recipe is 70% pale malt, 20% flaked barley, and 10% roasted barley with about 35IBU worth of bittering from english hops. In this recipe, I used 15% toasted flaked barley and 5% victory malt in place of the usual flaked barley to try and impart a toasty biscuity character. Yeast choice is actually quite varied in this style. One might think WLP004 (Irish Ale) would be the obvious choice, but that strain has quite low attenuation numbers, and a dry irish stout should be, well, dry. Higher attenuating english yeast or the good old california ale strain are both common picks. I went with WLP007 (Dry English Ale) which is on the higher end of the attenuation spectrum, and dropped the hop bitterness a little to compensate for the reduced residual sweetness.
I added about 1mL (yes, one milliliter!) of chalk to the mash after dough-in to keep the pH where it should be, and get a bit more calcium into the water as well.
Conversion efficiency was 92%, and extract efficiency was 72%. This is still more loss than I would like from the sparging process, but much better than last time. If I can get consistent extract efficiency around 75% in the long run I’ll be satisfied. The target rest temperature was 66.6C, which the oven did an amazing job of holding. I checked the temperature a few times, and it was never off by more than 0.2C. Here’s the mash at the end of the 80 minute saccharification rest . Delicious!
I elected to use a 15 minute boil addition to throw a touch more hop flavour into the mix than is typically present in a dry stout, but this should be quite a subtle difference when compared to the standard recipe. Wort chilling is a much quicker process now that the tap water temperature has plummeted to 10C. At the end of the brew day, 9L of 1.041 wort was collected, and I pitched the whole vial of WLP007. This would normally be overpitching, but this particular vial went through more temperature changes than usual during its trip to my fridge, and I lost some yeast exploding-pop-can style because I forgot to crack the vial before it warmed up, so the cell count below is a less accurate estimate than usual.
Batch Size: 9L
Boil Time: 65 min
Estimated OG (brewtoad): 1.043
Measured OG: 1.041
Estimated FG: (brewtoad) 1.010
Measured FG: 1.014
Estimated IBU (brewtoad): 31
Estimated SRM (brewtoad): 35
Estimated Extract Efficiency: 75%
Measured Extract Efficiency: 72%
1400g Maris Otter (Baird’s)
300g Toasted Flaked Barley
200g Roasted Barley (Baird’s)
100g Victory Malt (Briess)
Saccharification rest for 80 min at 66.6C, 2.6L/kg
Mashout for 5 min at 75C, 2.6L/kg
20g East Kent Goldings 5% AA @ 65 min
10g East Kent Goldings 5% AA @ 15 min
WLP007 Dry English Ale @ ~7.5 Million Cells/mL
18.11.13: Yeast pitched, temperature at 19C.
19.11.13: Water bath temperature steady around 18.5C, airlock activity beginning.
22.11.13: Fermentation essentially done, ambient temp raised for diacetyl rest.
24.11.13: Ambient temp lowered, water bath temperature now at 17.5C.
30.11.13: Still a little bit of activity! Water bath temp raised to 19C.
04.12.13: No more airlock activity, temp back down to 18C.
07.12.13: Bottled 8.5L with 50 grams of table sugar (2.4 Volumes).
Note: The measured FG was 1.014, higher than expected. However, the finished beer did not have very much residual sweetness. Perhaps there are lots of unfermentables in the flaked and roasted barley that keep the FG high, and brewtoad doesn’t account for these?