Beer: Milk Stout Nitro
Brewery: Left Hand Brewing Co.
Style: Milk Stout
ABV: 6 percent
Greetings, fellow scientists! Beer may seem simple on the surface, but there's a fair amount of chemistry, physics and other magical disciplines involved in both the creation and serving of our favorite drink. The devoted scientists at the Chow Bella laboratory are always hard at work investigating the mysteries of our favorite beverages to share with you, and our lead researcher is ready to take your questions. Today's topic: nitrogen. Prepare to be blinded by science!
What is nitrogen and what does it have to do with beer?
Oxygen and carbon dioxide get all the press, but nitrogen is the most abundant gas in our planet's atmosphere. It's an important element in draft beer -- most draft systems utilize a blend of carbon dioxide and nitrogen to push the beer along the lines, with the percentage of each gas varying based on factors such as distance, temperature and resistance. While CO2 dissolves in beer and can cause it to become overcarbonated, nitrogen tends to dissolve in beer less.
How does a beer that's carbonated differ from one served from a nitro-tap?
Nitro taps delivers beer pressurized with a higher ratio of nitrogen to CO2. Because our atmosphere is composed mostly of nitrogen, bubbles composed of the gas are less resistant to breakage. The result: a dense, long-lasting head that's a feast for the eyes and a silky, creamy body that's a treat for the mouth.
Why do the bubbles in a nitro beer seem to flow downward?
Perhaps the most visually stimulating aspect of a nitro beer is the way the bubbles seem to cascade toward the bottom of the glass, and the cause of this phenomenon is friction. While bubbles on the sides of the glass have to fight against the resistance of the glass' surface, the ones in the center rise without any struggle. The bubbles on the side of the glass flow downward to fill the space left by their quickly rising brethren.
Can you bottle a nitro beer?
Guinnes has done it for a while using widgets that release nitrogen, but Left Hand Brewing Co. recently perfected the art of nitrogenating a beer without the use of these tools. The breakthrough came after more than two years of research and development.
How do you they get the nitrogen into the beer?
Very carefully with tiny tweezers.
What's it taste like?
Nitrogen? Air, mostly. The beer, however, is the quintessential milk stout. Grab a bottle and pour it straight into the bottom of a tall glass -- this hard pour will knock the nitrogen out of and create the desired head. Colored a deep and inviting dark chocolate-brown, the brew's completely opaque with a two-finger head of light sandy tan that's as dense as pancake batter and seems like it might never leave. The aroma is laden with coffee, as espresso, milk chocolate, oven-roasted peanuts and toasted bread swirl. On the palate, first noticeable is bread that seems to have been charred to a crisp in a toaster. Peanuts, dark roast coffee and sweet cream appear soon after, and in that order, before acrid roasted malts return to linger on the palate at the finish. The mouthfeel, influenced by nitrogen as well as flaked oats and barley, is thick and smooth as whipped cream. Magnum and U.S. Goldings hops lend just a touch of bitterness -- 25 IBUs, to be exact.
Where can I get it?
Milk Stout Nitro is making its premiere in Arizona on Feb. 16 with a rollout that includes 14 different tastings in the greater Phoenix area. Bottles of milk stout nitro will start hitting the shelves after that. If you prefer the classic milk stout, fear not -- Left Hand will continue to brew the carbonated version of the beer as well.
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Thanks for visiting the Chow Bella lab. Until next time, nerds.
Food pairing suggestions:
Bold and filling, Left Hand Milk Stout is best after dinner next to a dessert. It's milky characteristics make it especially appropriate for chocolate baked goods like cake or brownies, but a cream-based dessert like panna cotta will provide interesting contrast.
Zach Fowle is a Certified Cicerone, an accredited guide to beer.