Volume Number: 21 (2005)
Issue Number: 12
Column Tag: Reviews

MacTech 2005 High-Tech Gift Guide

It Came Inside A Midnight Beer

by Aaron Adams

This Jingle Isn't A Bell

Company holiday functions populated by the inane and the insipid. A Christmas Eve spent with distant relatives, unseen since last Christmas, yammering on about the minutiae of their boring personal lives. Mounting credit card debt. The same boring Christmas specials that have been on television for twenty straight years. A freezing Saturday afternoon spent hanging uncooperative lights and decorations. In-laws.

What do all these things have in common?

Beer!

Whether it's being consumed on a silent night at home, at a holiday party, or to take the edge off of awkward social situations, alcohol is part of the holiday ritual for many of us. And what could be better on a cold winter night than an overstuffed recliner, a crackling fire, and a cold glass of thick, black, bitter stout? I speak, of course, of Guinness, the magic wonder brew that seems, at times, to be the solution to all of life's problems.

Guinness drinkers may have noticed of late a jingle in the can or bottle of their favorite holiday hops. That noise is none other than the Guinness widget, a clever device invented by Alan J. Forage and William J. Byrne, according to the widget's patent, which forms Guinness's characteristic creamy, foamy head once a can or bottle is opened.

What's so special about Guinness that it needs a widget?

Beers are carbonated to different degrees as a consequence of the yeast metabolizing sugars in the fermentation process. Sometimes additional carbon dioxide is dissolved into the brew as it is packaged. The dissolved CO2 in the beer causes the container to become pressurized. Later, when the beer is opened, the pressure is relieved and the CO2 bubbles out of solution to the surface and creates a head on the beer. Guinness is a little different. It contains less CO2 than most beers so nitrogen is added, which works in combination with CO2 to create the smaller bubbles that enable Guinness to have its thick, creamy head. The nitrogen dissolves into the beer, but not very well, so it bubbles out easily when the container is opened. The CO2 in Guinness, however, is more difficult to extract - the beer isn't saturated with enough CO2 for it to naturally bubble up and create a head during decompression.

Enter the widget (no, not that kind of Widget). The widget resembles a ping pong ball about 3 cm in diameter with a small hole 0.61 mm in diameter created by a laser. After the widget is dropped into an empty can, the can is filled with beer and a quick shot of liquid nitrogen is added. The can is immediately sealed and proceeds to pasteurization where it is heated to 60 degrees Celsius for 15 to 20 minutes and the liquid nitrogen in the can boils into gas. The expanding gas creates pressure of about 25 PSI inside the can, causing some of the nitrogen and beer, 10 - 15 ml, to be forced into the hole in the widget. The can and its delicious contents are then distributed to retailers.

Sometime later, the Guinness is purchased and opened. The pressure inside the can equalizes with the ambient pressure outside, and the beer and nitrogen contained inside the widget is forced out. The subsequent jet disturbs the Guinness around it, essentially shaking it from the inside out, and the remaining nitrogen and stubborn CO2 bubble out of solution, rising to the top to create the thick, creamy head Guinness is famous for.

This seemingly simple system took Guinness 20 years and more than 100 failed attempts to perfect.

Widgets are present in Guinness bottles as well as cans. The bottle widget works on a similar principle--compress nitrogen and beer in a plastic container and release the contents when the pressure changes--but is shaped like a rocket instead of a ball. When the bottle is opened, the rocket launches off the bottom, disturbing the beer inside and creating the head. Each time the bottle is tipped back for a drink, the rocket releases a little more foam-producing gas and the head on the bottle is topped off. And the rocket does have fins, not for aerodynamic reasons, but to keep the widget from exiting the bottle where it could be swallowed, hence ruining the taste of the beer.

This holiday season, take a moment to salute the geniuses ("Brilliant!") behind the widget when popping the top of a bottle or can of smooth black. Their contribution to seasonal stress relief is immeasurable

Aaron Adams is a network administrator, consultant, former star of Apple's "Switch" campaign, and an avid Guinness drinker. He can be reached via e-mail at adamsa@mac.com.