Thursday, September 24, 2015

Chocolate Butternut Squash Porter Recipe

Like my annual slice of pumpkin pie, I think I'm going to enjoy pumpkin ales more than I usually do. I never really love the standard formula: caramel-sweet amber/orange ale, overbearing spicing (sometimes augmented with ingredients like gram cracker flavoring), and no pumpkin flavor. Skilled brewers can make it work, one of my favorites is Selin's Grove's Pumpkin Ale, served only on nitro at the small central-Pennsylvania brewpub. The creamy head and subdued spice aroma combine to make it one of my favorites of the classic formulation.

As far as clean pumpkin ales go, stouts and porters provide a better base. As pumpkin-spice-latte devotees have discovered, restrained roast is an easy pairing for warming fall spices (cinnamon, allspice, ginger, nutmeg, clove, and vanilla). For beer, rather than add coffee to an amber base, I prefer chocolate and roasted malts. I brewed a small batch of Chocolate Pumpkin Porter seven years ago inspired by the description of Midnight Sun's TREAT (never having had it). Luckily I wasn't disappointed when I finally bought a bottle five years later!

For this batch, I originally intended to add canned pumpkin, but two local supermarkets weren't carrying it in early August. Instead I purchased two butternut squashes totaling 6.5 pounds. They are easier to dispatch than sugar/pie pumpkins thanks to smaller internal cavities, and their flavor is somewhat more characterful. Rather than roast the chunks of flesh, I steamed them, in the hopes of bringing out more of their squashiness.

With the flesh broken down enough to mash, I stirred in the Dutch-process cocoa powder, custom pumpkin pie spice mix, vanilla bean, and a half tin of black treacle (the English cousin of molasses - light molasses would be an acceptable substitute) and continued to cook the mixture a few more minutes. This took the place of the standard "blooming" process I usually execute with cocoa powder (rehydrating it with hot water). Unrefined sugar and vanilla compliment chocolate, they help to make it taste more deeply chocolaty. In this case I didn't want the treacle to be strong enough to identify, but something you'd miss if it was taken away.

I dumped the resulting "vegan brownie batter" into the fermentor and pumped the cooled wort on top of it. Squash has relatively little starch, so it isn't necessary to convert it in the mash. You could add it to the boil, but I find it imparts more flavor during extended contact in the fermentor (it settles out pretty well if given enough time). In the past I've added a spice tea at bottling/kegging when I want to taste the "true" spice flavor (as opposed to Belgian-style late-boil addition for spice complexity), but I wanted to try this method. At packaging I tasted the beer and decided it didn't need a spice boost.

This was only half of the batch, I left the rest as a plain porter - although I have a twist planned for it before it goes on tap... I'll talk about the base recipe (including stout malt) when I post the tasting notes for it.

Chocolate Butternut Porter Tasting

Appearance – As chocolate brown as a beer can be without being black. You get the feeling this would be a pretty ugly (muddy) beer if it weren’t so dark. Between the cocoa powder and the squash, there is plenty of haze when viewed at the margins. The head is creamy, but not as long-lasting as some of my other nitrogenated beers.

Smell – Rounded cocoa-roast leads, followed up by cinnamon (and other more nebulous fall spices). Like a spiced chocolate muffin, it doesn’t smell too sweet, with fresh bready maltiness filling out the background. Lots of different spice notes as it warms (nutmeg especially), luckily the clove is subdued. The squash comes through in the same way it does in pumpkin bread, as a pleasant sweet vegetable note.

Taste – Spices are saturated through the palate without overwhelming the other flavors. They aren’t as bright and distinct as when I’ve used a spice tea, but with such a complex beer this technique worked well. The chocolate is behind the spice, mixing with the roast. The treacle and vanilla are faint. Sweet enough to support the autumnal flavors, without being sticky. The squash flavor is subtle at best, but it adds a slightly fruity-savory flavor in the mid-palate. The flavors of the base beer itself are a bit lost with so much else going on, the hops and yeast are all but absent.

Mouthfeel – Really silky, one of the most viscous, unctuous, full bodied beers I’ve brewed! Especially considering the moderate alcohol. I’m sure the flaked rye and high FG helped, but I have to imagine the starches and fiber in the squash played a role as well. Carbonation is low, but the dense head only adds to the luxuriousness.

Drinkability & Notes – It’s a fun beer. Balanced, expressive, and drinkable for what it is. However, it’s such a rich/full beer that it isn’t exactly a second or third pint sort of beer. Glad I got it on early in the season so I can slowly enjoy it through the fall!

Chocolate Butternut Porter Recipe

Recipe Specifics
Batch Size (Gal): 6.00
Total Grain (Lbs): 15.00
OG: 1.066
SRM: 43.0
IBU: 24.2
Brewhouse Efficiency: 75 %
Wort Boil Time: 75 Minutes

66.7% - 10.00 lbs. Malting Company of Ireland Stout Malt
13.3% - 2.00 lbs. Flaked Rye
6.7% - 1.00 lbs. Weyermann CaraMunich III
3.3% - 0.50 lbs. Weyermann Carafa II
3.3% - 0.50 lbs. Simpsons Chocolate Malt
3.3% - 0.50 lbs. Simpsons Medium Crystal
3.3% - 0.50 lbs. Briess Midnight Wheat

1.13 oz. Crystal (Pellet, 3.25% AA) @ 60 min.
0.50 oz. Sterling (Pellet, 8.00% AA) @ 60 min.

0.50 tsp Yeast Nutrient @ 6 min. (boil)
0.50 Whirlfloc @ 6 min. (boil)
6.50 lbs Butternut Squash
1 Vanilla Bean
5 oz Dutch Process Cocoa Powder
2.75 tsp Pumpkin Pie Spice
0.50 lbs Tate & Lyle's Black Treacle

WYeast 1318 London Ale III

Water Profile
Profile: Scandinavian RIS

Mash Schedule
Sacch Rest - 45 min @ 158F

Brewed 8/9/15

Made a 4L starter 24 hours in advance. Good activity quickly on the stir-plate.

2.25 g of chalk to the mash (dissolved in carbonated water first). Mash pH 5.34

Spice: 1.5 tsp cinnamon, .5 tsp grated nutmeg, plus .25 tsp allspice berries, and .5 tsp cracked ginger ground in a coffee grinder with 5 cloves.

6.5 lbs butternut squash peeled and diced, steamed with 1 cup water. Uncovered after 30 minutes, mixed in spices, 5 oz of Hershey's Special Dark Cocoa, 8 oz of Tate & Lyle's black treacle, and 1 split vanilla bean. Cooked 5 minutes uncovered. Then pulled off heat to cool, covered.

Collected 7 gallons with 1.5 gallon cold sparge. First runnings 1.059.

Added 4.5 g of sea salt to the boil. Chilled to 64 F with recirculated ice water.

Racked 5.5 gallons to each fermentor, one had the cooled chocolate-squash-spice paste. Shook to combine, pitched decanted starter, left at 64F to ferment.

8/15/15 Upped to 68 F to finish.

8/30/15 Kegged both halves with 2.35 oz of cane sugar each.

9/13/15 Hooked Butternut half up to beer gas in the kegerator. FG 1.026 (61% AA, 5.3% ABV). Likely a little higher alcohol and attenuation considering I didn't take an OG reading after mixing in the squash mixture.

9/23/15 Tasting notes above.

2/9/16 Tasting notes and process for the "plain" half, revived with cold-steep dark malts in the keg.


AndroidMike said...

Love the idea of the chocolate paste! Might have to try this recipe some time.

BTW, love your site. Thanks very much for all the good info (halfway through your sour book too)! Cheers

Tony B. said...

Can you comment on the salt addition? Were you trying to get the sodium up to a certain level or increase the chloride? Or both? Adding salt to a beer seems to have had a stigma associated with it that's been fading recently. I like a touch in a darker beer, but haven't experimented enough to have a firm opinion on just how much.

Cheers! Tony

James said...

"With the flesh broken down enough to mash..."

I definitely misread that as an indication that the stuff was going in the mash.

The Mad Fermentationist (Mike) said...

I was looking for both sodium and chloride, but not a huge amount of either. At .75 g per gallon of finished beer that's 80 PPM of sodium and 120 PPM of chloride (about 1/3 of what I've added for gose). My mother swears by a pinch of salt in hot chocolate. Sodium helps to heighten the chocolate flavor there as well as here. The chloride helps to boost the body as well. They are purely flavor active, so you can always pull a sample and dose to taste if you are interested in trying it before committing!

I was trying to phrase that to make it clear that it wasn't added to the mash, guess I didn't succeed!

Ben said...

What's the thinking between the 2 different types of hop at 60min? Just what you had around?

The Mad Fermentationist (Mike) said...

Exactly, this is the sort of beer/addition that I try to use up odds and ends just aiming for the target IBUs. Way too many varieties in the freezer with the new harvest right around the corner!

Unknown said...

Hi Mike. Can you clarify this:

"Batch Size (Gal): 6.00 "

"Collected 7 gallons..."

"Racked 5.5 gallons to each fermentor..."

How did you manage 11 gallons from a 6 gallon batch? Was it meant to say 3.5 galons to each fermenter? I'm thinking of trying this recipe, but with a full batch on the squash and chocolate. I'm trying to figure out if I need to double the extras for a regular batch.


The Mad Fermentationist (Mike) said...

I scaled the recipe down so it makes sense if you want to brew it as just the Chocolate Butternut Squash version. I've gone back and forth, it generally seems more confusing to people when I post it as I brewed it.

Jeffrey Paul said...

Love this! I'm about to brew a PSL stout, where I'll do a coffee milk stout with pumpkin and a touch of spice. I like the paste idea...I will probably do something similar. I really like the idea of the pumpkin and spice mixture going right into the fermenter.

Infinity Racing said...

Mike, what do you think about adding the spice/squash paste to the secondary? I just brewed a porter this last weekend and am thinking about splitting the batch to secondary half of it on the spices/squash. Then I would probably leave it to secondary for two weeks.

Think that would be enough?


Infinity Racing said...

Not sure if my comment went though...

What do you think about doing the spice/squash mix for the secondary. Just brewed a porter and might do a split batch. Think 2 weeks would be enough to impart flavor. If i'm doing it in the secondary do you think I should put the mixture in a hop bag so that it doesn't make the beer too cloudy?


The Mad Fermentationist (Mike) said...

I was getting so much spam (including 100+ in Arabic one morning alone) that I had to turn on comment moderation for older posts.

I'm sure adding to secondary would be fine, I just don't secondary many of my beers. Two weeks sounds like plenty of time. You may want to give the fermentor a swirl after it is filled to get the squash into suspension. Not sure how well it would work bagged, it seems to settle out pretty well. There is some starch in the squash, but I wouldn't worry too much about clarity in a dark beer.

Infinity Racing said...

Why don't you usually secondary? In your 11 tips for new home brewers I thought you recommended doing a secondary?

The Mad Fermentationist (Mike) said...

I'd suggest rereading the 11 Mistakes post, I specifically suggest against using a secondary in most cases.