It’s in the can: Mathematical formula holds secret to perfect Guinness head

FINALLY, after spending millennia defending their work from claims it has next to no relevance to daily life, applied mathematicians have found a fool-proof equation to support their profession.

And, with just days to go until St Patrick’s Day, the discovery could not have come at a more appropriate time.

New research from the University of Limerick has uncovered a potentially lucrative answer to the age-old riddle of how to get a perfect head on a poured can of Guinness.

The issue had previously resulted in the brand’s owners Diageo spending a small fortune on a device called the widget in an attempt to solve the problem.

However, led by Prof Stephen O’Brien, the research team of applied mathematics lecturer William Lee, intern Scott McKechnie and Phd student Michael Devereux, have uncovered a far simpler solution.

As stouts bubble less than lagers or other carbonated drinks when poured because they contain dissolved nitrogen as well as the carbon dioxide that drives the fizz, Guinness poured from a can regularly has a below-par head.

However, using a mathematical equation, researchers from UL’s Mathematics Applications Consortium for Science and Industry group have found that adding nitrogen makes the drink less acidic — giving it a longer- lasting head with small bubbles which are key to a stout drink’s smooth texture.

As such, the mathematical equation-based research published in the highly-regarded Nature science journal could make existing solutions to the problem obsolete.

“It really came about by chance,” Mr Lee told the Irish Examiner.

“We had an intern in last year, Scott, and I gave him a task to do, more with the purpose of showing why Guinness doesn’t get a good head and the science behind it.

“He came back and said if you add this or that it would work, so I obviously went back and checked his results, and was more than surprised.

“You need about 100 million bubbles to get a proper long-lasting head.

“Our model suggested that stout should in fact produce bubbles, and when poured onto cellulose fibres there were bubbles everywhere,” he added.

While to date no stout-makers have contacted the researchers, the details behind the published study will have a significant impact on the drinks industry.

The research is also likely to come in useful for anyone who faces the trauma of being handed a can of the dark stuff.

Punters can now rest assured that even complicated mathematical riddles are on their side when fishing out change come the last orders call.

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