Chris Lennert, COO at Left Hand Brewing Co., explains it best in the video above: “It’s a little beautiful top hat. We pull little rabbits and magic out of it.” He’s explaining the tiny plastic widget that sits at the bottom of Left Hand’s Milk Stout Nitro cans that releases nitrogen when the can is opened to create wonderful draft quality beer on the go. Left Hand turned to Ball Corp. to help engineer nitrogenating in can form, and they both discuss it in the mini movie above.
It works like this: White, plastic, top hat-looking widgets are placed in the bottom of the Milk Stout Nitro cans. After filling with beer, liquid nitrogen is added, and the cans are sealed. Then, those cans get inverted, giving those widgets the head space. Soon, the liquid nitrogen turns to gas and expands by about 300 times. The widgets capture that gaseous pressure, and when the cans are opened, the nitrogen gas escapes through little holes in the widgets, agitating the beer, creating the nitrogen effect.
Or, just watch the video above. It explains it far better. Plus, you get to watch … mmmmm…. cascading bubbles.