Tuesday, February 10, 2015

Toasted-Coconut Vanilla Milk Stout... On Nitro!

A half pint of toasted-coconut vanilla milk stout!This coconut-vanilla milk stout is my first beer carbonated and served with beer gas through a stout faucet. A "normal" tap essentially gives the beer a clear path from keg to glass. As a result, most of the carbonation stays in solution, ideally with just enough agitation to cause the desired head to form. Many bars push their beers with a blend of carbon dioxide and nitrogen to provide more pressure to push over long lines without dissolving excess carbonation in the beer. Nitrogen is only about 1% as soluble in beer as carbon dioxide, so not much ends up in the glass (especially with how quickly most large bars run through kegs).

With a stout tap the beer is forced through a restrictor plate (essentially a disk with a few small holes) before a flow straightener puts it back into a stream. This knocks most of the carbonation out of solution, producing that beautifully-cascading creamy head, with almost no carbonation left in the beer itself. The beer gas (70-75% nitrogen) provides the push. If you tried pushing with 30-35 PSI of pure carbon dioxide, so much would dissolve that the beer would pour nothing but foam.

Guinness is the archetype for beers served via a stout faucet, but it is a popular choice for dark beers from Old Rasputin to Black House. Low dissolved carbon dioxide tends to mute aromatics, so I shy away from IPAs served this way (which seem to be a popular choice).

Many brewers carbonate their beer with straight carbon dioxide, and then serve with beer gas. The mix is still required (rather than straight nitrogen) to prevent the beer from going flat as it sits on tap. No matter how much nitrogen head-pressure there is, carbon dioxide will come out of solution if its head-pressure is lower than what is in the beer. I did the carbonating/nitrogenating with beer gas in the hopes that some nitrogen would dissolve. Whether it did or not, the results are terrific!

Coconut-Vanilla Milk Stout

Appearance – Pours pitch black with a three-fingers of super-dense, brown head. Like a darker Guinness. There is no substitute for a stout faucet, love those swirling bubbles!

Closeup of the fine bubbles produced by beer gas and a stout faucet.Smell – Balance of toasted coconut, vanilla, and coffee. Not fake or artificial. The roasted barley comes through nicely, fresh grain. Otherwise clean and pleasant. Not leaping out of the glass, but plenty of enticing aromatics.

Taste – The flavors are similar, but more potent than the nose. They are joined by substantial sweetness. The coconut is there, but not to that coconut doughnut level. The vanilla blends with it well. The stout serves as a good base, with the roast helping to balance some of the sweeter flavors. Long finish, makes up for the lack of aroma. There is a hint of hop bitterness, but it quickly vanishes.

Mouthfeel – One of the fuller-bodied 5% ABV I’ve tasted. Almost no carbonation, just a faint tingle on the tongue when held. Coating, chewy, silky, and decadent.

Drinkability & Notes – A WOW beer! Bold sweet flavors, without being overwhelming or obscuring its beery-essence. Doesn't really remind me of a bourbon barrel stout as was my goal (would need to be drier and more potent), but it was still a great idea! Despite the oddball ingredients, I wouldn't call it a gimmick beer.

What makes a beer gimmicky anyway? I suppose it is one of those things that everyone thinks of the brewer one down the line. Germans think Belgians are gimmicky, Belgians the Americans, Americans the Danish etc. For me it’s about what’s in the glass. I added toasted coconut and vanilla beans rather than Mounds candy bars, or extracts, because I suspected they would add more of the flavors I wanted, without drawbacks. The beauty of homebrewing: making beers that only have to suit your tastes and opinions!


Unknown said...

I've been looking forward to this post, as the recipe post was enticing... and glad to hear it was a success!

So, say you were a guy without a fancy nitro tap. Is there anything you would change about the recipe?

Oh and please forgive the "Unknown" - I am internet unsavvy apparently can't figure out how to post without a blogger profile.
Jake from Madison WI

The Mad Fermentationist (Mike) said...

I'd just say aim for low carbonation, whatever your method. Nothing disrupts rich, velvety, and roasty like sparkling!

Years ago I had the blog open to comments from anyone. Spam got worse and worse. Then I added a CAPTCHA. Worked for awhile, before Spam got out of control. Forced me to go to accounts, and still I get a few annoying ads every month.

Brian said...

Mike, just curious how long it took you to carbonate using only the beergas. I've only done one beer on Nitro so far, and I initially carbed with CO2, then put it on beergas. I found that the head came out great, but didn't last as long as a typical Guinness head you'd get on tap that typically lasts for most of the glass. Wondering if carbing with beergas helps with this

The Mad Fermentationist (Mike) said...

Some sources do claim that because air is mostly nitrogen, having dissolved nitrogen in the beer does help head retention. Not sure on that because of how little nitrogen actually dissolves into the beer. It could be the other factors that go into head retention at work: protein structure, hopping rate, glass cleanliness etc.

Unknown said...

Great write up. Very envious of your new keezer set up. I whole-heartedly agree with your comments on nitro ipas. I haven't tasted one yet that led me to believe that it added anything. Cheers

Matt said...

This is a great beer.

Unknown said...

How long did you leave the beer on the coconut and vinalla beans?

The Mad Fermentationist (Mike) said...

I added the coconut and vanilla five days before kegging. All the timing details are in the notes at the bottom of the recipe post.