Barack Obama was right: Guinness really does taste better in Ireland

Barack Obama drinks Guinness on his visit to Ireland
Barack Obama enjoys a Guinness at Ollie Hayes pub in Moneygall, Ireland, on Monday. 'Youre keeping all the best stuff here!' he joked. Photograph: AP


"The first time I had Guinness," Obama said, "is when I came to the Shannon airport. We were flying into Afghanistan and so stopped in Shannon. It was the middle of the night. And I tried one of these and I realised it tastes so much better here than it does in the States ... You're keeping all the best stuff here!"

Maybe he's right. According to research published in the Journal of Food Science in March, Guinness does not travel well.

Like all great funny stories to come out of a pub, it started with an Irishman, an Englishman, a Dutchman and a German walking into bars. They spent a year of their spare time (probably quite happily) testing the stout in 14 different countries.

During what the authors lightheartedly describe as "extensive pre-testing", a number of factors that might be involved in making the perfect pint were considered. This included such things as the height of the head on the pint, its temperature and its flavour.

In addition, to capture the entire experience, factors such as the temperature of the pub, the sex and nationality of the bartenders, their level of experience and pint-pulling technique were also considered.

They were certainly thorough. Even the presence or absence of female company was considered: it turned out that having women drinking companions did not "inflict any unplanned blinding of the testers, who were all dedicated to the measurements".

From the variables measured, the authors were able to score each pint using a specially designed Guinness Overall Enjoyment Score (GOES) which allowed the drinking experience in different countries to be compared. They used what is known as Student's t-test: a relatively simple way of establishing whether there are significant differences between two groups of data, in this case, between pints in Ireland and pints consumed outside Ireland.

This is particularly apt, given that the t-test was developed at the Guinness brewery in Dublin by one William Sealy Gossett. In 1908, Gossett developed the test to monitor and improve the average annual yield of barley. Due to the competitive advantage using the test could provide over other brewers, Guinness was reluctant to let Gossett publish the work under his own name, so he used the pseudonym Student.

The results of the Guinness-tasting t-test were clear. Pints consumed in Ireland had a mean GOES score of 74, compared with a score of 57 in pubs outside Ireland. While Ireland may not necessarily keep the best stuff to itself, the science is clear: Guinness tastes better over here.

Eoin Lettice is a lecturer in the School of Biological, Earth and Environmental Sciences at University College Cork, Ireland. He blogs at Communicate Science