The start of the journal entry for my most recent batch of dry stout lists the changes from the previous batch. I did not expect much impact from the changes, so I felt comfortable changing five things at a time. Now that the new batch has fully conditioned and I can really appreciate it, I can say it is significantly different from the first. There are no overt flaws, but
- The roast flavor is harsher
- The body is thinner
- The head is lighter in color, thinner, is not long lasting, and leaves little lace
I want to look at the changes to see what I might want to do next time.
Changes in Base Malt
In batch 29, I used Thomas Fawcett & Sons Halcyon. In batch 32, I used Crisp Maris Otter. Country Malt Group is the exclusive distributor of Thomas Fawcett & Sons malts in the United States. Here is what they have to say about these two malts:
- Fawcett Maris Otter (2.3–3.0°L)
- Maris Otter has long been the favorite of English brewers for its brewhouse performance and rich, slightly nutty flavor. An excellent malt for any English beer style. All of Fawcett’s Maris Otter malt is still produced in their traditional floor maltings.
- Fawcett Halcyon (2.3–3.0°L)
- Halcyon is a barley variety that was bred from the Maris Otter and Sargent barley varieties. It tends to produce a less sweet wort than Maris Otter.
Also, while some variation between maltsters is to be expected, the discussion online indicates that Crisp Maris Otter is almost indistinguishable from Thomas Fawcett & Sons. So, if anything, batch 32 might be slightly sweeter than batch 29 as a result of this change.
I do not believe this change had much, if any, impact and will continue to use Maris Otter, as I am trying to standardize on a single base malt.
Changes in Roast Barley
As I said in the notes to batch 32, I thought I had a significantly different roast barley. Instead, I used one that was nearly identical. Even though the roast flavor is different between the two, I do not believe the selection of the malt is the cause.
Changes in Yeast
This was just serendipity and frugality. I had a second-generation cake of West Yorkshire Ale yeast that was going begging, so I used it. Yorkshire has never been known for their Dry Stout. The two chief areas have, and continue to be, London, characterized by the London Ale strain, and Dublin, characterized by the Irish Ale strain.
Wyeast has this to say about the Irish Ale yeast:
- YEAST STRAIN: 1084 | Irish Ale™
- This versatile yeast ferments extremely well in dark worts. It is a good choice for most high gravity beers. Beers fermented in the lower temperature range produce a dry, crisp profile with subtle fruitiness. Fruit and complex esters will increase when fermentation temperatures are above 64°F (18°C).
This is what they say about the West Yorkshire Ale yeast:
- Wyeast 1469-PC West Yorkshire Ale Yeast
- This strain produces ales with a full chewy malt flavor and character, but finishes dry, producing famously balanced beers. Expect moderate nutty and stone-fruit esters. Best used for the production of cask-conditioned bitters, ESB and mild ales. Reliably flocculent, producing bright beer without filtration.
It may be that some of the flavor difference is from a slight increase in fruity esters from the West Yorkshire Ale yeast. In the future, I will be using Irish Ale yeast.
Changes in Mash Schedule
This may be the single largest contributor to the change between the batches.
In my notes for batch 29, I referenced John Palmer’s How to Brew:
The typical Protein Rest at 120–130°F is used to break up proteins which might otherwise cause chill haze and can improve the head retention. This rest should only be used when using moderately-modified malts, or when using fully modified malts with a large proportion (>25%) of unmalted grain, e.g. flaked barley, wheat, rye, or oatmeal. —John Palmer
At the time I expressed curiosity at the need for a protein rest, but I think I have seen the value. I believe the “thinness,” both in the head and the body, may be from this one change.
From a process standpoint, I did get a stuck mash on batch 32. The recipe does consist of 30% unmalted grain. The protein rest on batch 29 may have helped with this.
Changes in Brewhouse Efficiency
This certainly had an impact, though I am hard pressed to explain what happened. Let me try.
I have simplified my process, based on my system and the typical beers I brew, to use 5 gallons of liquor in the mash and 3½ gallons to sparge. This leaves me with 6.7±0.2 gallons at the start of the boil and a mash thickness of 1 to 2 quarts per pound.
When I came up with the infusion mash schedule for batch 29, I was very careful to make sure I ended up with 5 gallons of liquor in the mash. Despite my efforts, I ended up only getting 6⅜ gallons of wort at the start of the boil.
On batch 32, I used my normal single infusion mash, but ended up with 7⅛ gallons of wort at the start of the boil.
Both batches seemed to be outliers: one high, one low. Both had a 16% boil off rate and both had 71–72% attenuation, leaving batch 29 at 6.9% ABV, well above the BJCP range of 4 to 5% for a Dry Stout, and batch 32 below, at 3.7%.
I think next time, I will follow the same process as batch 29, but check the volume and gravity after the sparge. I will add water to adjust the boil gravity to the expected volume to end up around 4.5% ABV.
Plans for the Next Batch
Here is what I am planning for the next batch of Night Horse based on this analysis:
- Crisp Maris Otter base malt
- Crisp Roasted Barley run through the mill twice
- Wyeast 1084 Irish Ale™ yeast
- Protein rest at 120 °F for 15 minutes, followed by saccharification rest at 150 °F for 60 minutes.
- After collecting the second runnings, adjust the boil volume to target 4.5% ABV, assuming a 16% boil off rate and 72% attenuation.