Monday 10 April 2017

Brewing a Coffee Milk Stout

When you're really into hoppy beers and sours, sometimes it's a little too easy to get caught up in brewing those styles, so much that it can lead to forgetting to brew other, almost-as-delicious beers. By late December (yeah, I'm behind in posting again), it occurred to me that I hadn't brewed any really dark beers in quite some time; when I looked at my brew log, I was surprised to see it had been even longer than I originally thought. I brewed a Black IPA in November, 2015, and that's still a hoppy beer; the last time I had brewed a Stout was in May of 2014. Yikes!

For someone reading this blog, you couldn't be blamed for assuming I don't normally drink dark beers like Stouts or Porters. While my beer consumption definitely leans heavily towards lighter, hoppier (or Belgian) styles, I still really do enjoy darker beers as well. The last Stout I brewed was a Sweet Stout (aka Milk Stout); this was the second time brewing this recipe, with a few tweaks, and it was a very tasty beer. Sweet Stouts are great because they give you plenty of roast character, plus a little bit of extra sweetness and mouthfeel from the addition of lactose powder. Throw in that they're in the 4-6% ABV range, and you're laughin'.

I was originally going to just brew up the same Sweet Stout recipe as before. However, I've been drinking more and more excellent Coffee Stouts lately, and the more I thought about it, the more I figured coffee in a Sweet Stout would be a fabulous addition. And it turns out I'm not the only one, as there's plenty of commercially brewed Coffee Sweet Stouts out there; I just didn't discover them until after. Oops.

When it comes to adding coffee in beer, there are many methods. I won't do what others have done and list them all here, but brewers definitely feel strongly about some over others. Personally, I had no desire to add coffee beans in the mash, or the boil, or in primary, as I suspect (and others have confirmed) that at least some coffee character is ultimately lost during fermentation. I narrowed it down to two other approaches: adding cold-brewed coffee at packaging, or adding coffee beans for a short time in secondary.

The former approach seems to be the most popular one used, and I can see why, especially when you're talking about a commercial-size batch. You can brew a concentrated, large batch of coffee and add it to a brite tank, as opposed to trying to add (and eventually remove) a crapload of beans. We homebrewers, luckily, don't have to worry about stuff like that! While I initially was planning on taking the cold-brewed approach, I decided on adding beans in my dry-hop keg with the beer - the filter I have in there would work perfectly for transferring the beer to the serving keg (via CO2), with very minimal clean-up. And after talking with Derek Dellinger of Kent Falls Brewing, who has had success with this method as a homebrewer, it made more sense to me.

But, how much coffee? I really didn't have anything to go by, experience-wise, but after speaking with several friends who have brewed with coffee, I settled on 150 grams of beans for a 5.5 gallon batch. I preferred to use coffee that wasn't your typical blend, and luckily had recently met up with Kent and Tanji, two good friends who live in Freeport, ME. They own a coffee roasting business, Freeport Coffee Roasting, and they're turning out some really excellent products (I suggest you check them out and order some... don't worry, I don't work for the White House, nor do I have any business ties to any coffee companies, so it's ok!). I used their Kenya Kichwa Tembo, a medium-roast described as "citric, floral, with medium acidity" (Note - this is why I like coffee beers - you could use so many different types of excellent coffee and always have a different result).

For my grist, I went with the same recipe as I've used in the past - Maris Otter as the base, some Black Patent, CaraMunich, Pale Chocolate malt, and a full pound of lactose sugar added during the boil. In my experience, this produces a beer that is roasty, creamy, and only slightly sweet. Bittered to just ~20 IBUs (use whatever variety you want at 60 mins), I fermented the beer with London Ale III. Why? Because it was the only English strain I had on hand. I've used Irish Ale before, and that worked great, but I figured with the roast character and coffee, LAIII would do fine.

I brewed and fermented the beer, then racked it to my dry-hop keg on top of the coffee beans. After about 30 hours (Derek had said roughly a day should do the trick), I pushed the beer to the serving keg with CO2, and carbed it up. It was really nice to have a dark, non-hoppy beer on tap for a change (the beer just kicked a week or so before I finished this post), and for my first go at a coffee beer, I was pretty happy with it. The coffee character was perfect for me; I've definitely had coffee stouts with MORE coffee presence, but too much coffee can overwhelm some of the actual beer, in my opinion. The beer is pretty creamy; I think the lactose could come through a bit more, which may have to do more with the coffee shadowing it a bit. I can't imagine more than a pound of lactose powder is necessary.

So, what would I change? I think I'd cut back on the coffee just a bit (maybe down to 125 grams to start), and I'd like to try a coffee blend with a little less acidity, which I think would let the lactose sweetness come through some more. Overall, though, a really nice beer that was very popular with most of my beer-drinking friends (yeah, yeah, it's free, of course they're going to say they liked it!), and definitely one I'll be coming back to tweak in the near future. My recent trip to San Diego allowed me to bring back some Modern Times coffee, so look for a follow-up, soon.

Recipe Targets: (5.5 gallons, 75% efficiency) OG 1.060, FG ~1.020, IBU ~21, SRM 37, ABV ~5.3%

Grains & Sugars:
4 kg (74.7%) Maris Otter
400 g (7.5%) Black Patent
300 g (7.1%) CaraMunich
200 g (3.7%) Pale Chocolate malt
454 g (8.5%) Lactose sugar (added during the boil)

Polaris - 10 g (17% AA) @ 60 min

1/2 tab Irish Moss at 5 min
150 g Coffee beans (Freeport Coffee Roasting Kenya Kichwa Tembo blend)

Yeast: Wyeast 1318 London Ale III (with a starter)

Water: Fredericton city water, carbon-filtered; 4 g Gypsum and 6 g calcium chloride added to mash

- Brewed on November 30th, 2016, by myself. 50-minute mash with 14 L of strike water; mash temp on target of 152 F. Mashed-out for 10 minutes with 6.75 L of boiling water to 165 F. Sparged with ~3.75 gallons of 168 F water for final volume of ~6.75 gallons.

- 60-minute boil. Final volume ~5.5 gallons; OG 1.062. Chilled to 64 F, then poured into Better Bottle. Aerated with 70 seconds of pure O2, pitched yeast at 65 F.

Appearance: Pours with a moderate-low, tan-coloured head that fades fairly quickly to a thin ring. Body is jet-black in colour and opaque.

Aroma: Even weeks after kegging, the coffee aroma is still coming through wonderfully - roasty, slightly floral as promised.

Taste: Big flavours of roast from the coffee, and I'm really digging the slightly acidic, citrusy flavours that go along with it. Slightly sweet, could probably be a bit higher in that department.

Mouthfeel: Medium-bodied, medium-low carbonation.

Overall: For a first attempt, I'm pretty happy with this one. I think this particular coffee works really well in a stout like this - the blend of acidity, roast, and citrus and floral notes is spot-on. Changing the grist a bit, and decreasing the coffee slightly, may help bring out the sweetness a bit more; I don't really think adding more lactose powder is the answer. I'm also happy with doing the bean-steep as a means of adding coffee, as it's pretty simple and effective, from what I can tell.