Left Hand Brewing Co. is about to introduce what it is calling "craft beer's first nitrogen bottled beer."
The beer, Milk Stout Nitro, is hitting the Boston area this week in a series of events that include tastings at more than a dozen liquor stores and "rollout parties" at five local bars.
When a beer -- typically a stout -- is dispensed with a lot of nitrogen, it pours creamy and contains less carbonation. Most draught beer is dispensed with either pure carbon dioxide or a blend that contains a little nitrogen. Some bars put a stout or two "on nitro," using a mix that is roughly 75 percent nitrogen. Some canned beers -- Guinness, for instance -- are packaged with nitrogen, and a ball-like widget floating in the can helps create creamy head.
Left Hand's Milk Stout Nitro accomplishes the same thing in a bottle, without a widget. The brewery says the bottle is specially designed to help create a creamy head, so long as the beer is "poured hard" into a glass.
Poured hard I did. The beer cascaded into the glass, starting tan and gradually turning black over 30 seconds or so. When it was through cascading, a tan head settled on top -- milky and lumpy, like ice cream on a root beer float.
The beer is a twist on Left Hand's popular Milk Stout, which contains lactose and residual sugars that make it a bit sweeter than other stouts. Chocolate and coffee overtones came through in the aroma and taste, and the beer had a wonderfully milky mouthfeel. Cold, thick, and creamy, it was outstanding.
Milk Stout Nitro is 6 percent alcohol by volume. A six-pack costs about $11.
Here's the schedule of this week's Milk Stout Nitro events:
Thursday, 5 to 7 p.m.: tastings at Craft Beer Cellar in Belmont, Gordon Liquors in Waltham, Downtown Wine & Spirits in Somerville, Julio's Liquors in Westborough, Ball Square Fine Wines in Somerville, and Blanchard's Liquors in Allston, Jamaica Plain, and West Roxbury.
Friday, 5 to 7 p.m.: tastings at Kappy's Fine Wine & Spirits in Medford, Wine Emporium in Boston, Supreme Liquors in Cambridge, Marty's Liquors in Newton, Martignetti Liquors in Brighton, Brookline Liquor Mart in Allston, Whole Food Market in Allston, and Upper Falls Beverage Store in Newton.
Rollout parties will be held Thursday night at 8 at Meadhall in Cambridge, Cornwall's in Boston, and the Armsby Abbey in Worcester; and Friday night at 8 at Sunset Grill in Allston and Green Street in Cambridge.
Left Hand, based in Longmont, Colo., has provided these FAQs about Milk Stout Nitro:
Q: Where do you get your nitrogen?
A: We use only local, organic nitrogen that has not been fed any GMOs.
Q: Do you use a special bottle?
A: The bottle is specifically designed to release the beer as you empty it.
Q: What does the n2 do for you?
A: Nitrogen forms small densely packed bubbles which create a beautiful head on beer. Nitrogen bubbles are also less resistant to breakage in the atmosphere, because our atmosphere is mostly nitrogen. This lends itself to long lasting, visually stimulating head.
Q: Why does it cascade?
A: It is due to the friction on the side of the glass. The bubbles on the side of the glass have to fight with the friction of the glass surface. The bubbles in the center rush up the middle and then get pushed to the side by the bubbles behind them. This causes a downward flow on the sides of the glass as they cannot flow up they flow down into the center and out.
Q: What made you decide to do this?
A: Our Milk Stout Nitro bottle is designed to replicate our draught product that has been to successful. We love drinking our beer in our bars and restaurants, but wanted people to have that same experience at home.
Q: When do you add the nitrogen?
A: It starts in the brewhouse with designing the beer. We also take specific steps during fermentation, filtration and packaging to end up with the nitrogenated beer.
Q: How do you get the nitrogen into the beer?
A: Very carefully with tiny tweezers.
Q: Why don't you use a widget?
A: We found that due to the unique physical properties of our Milk Stout, the development of a widget would be an unnecessary waste of millions of pounds, er, dollars.
Q: Why is it necessary to "pour hard"?
A: In order to force the nitrogen out of solution in the beer to create the desired head. This is similar to using a restrictor plate on a draft nitro faucet.
Q: Whose idea was this?
A: It was a total team effort. It didn't take long for the whole company to buy in as we strived to become the first craft brewery to put nitro beer in a bottle.
Q: What about regular (CO2) Milk Stout 6pks?
A: We will continue to brew and package Milk Stout 6pks. We have found that some customers prefer Milk Stout carbonated with CO2, which is more effervescent, where others prefer Milk Stout Nitro for its silky smooth creaminess. Why deny our fans either one?