New Technology Creates a More Eco-Friendly Head on Your Guinness

Just in time for St. Patrick's Day, Irish mathematicians discover a biodegradable alternative to the plastic widget in cans of Guinness.

As St. Patrick's Day draws near, many of you may be anticipating a nice chilled glass of Guinness, complete with a creamy foam head. But if you're not propping up a bar in Ireland, and are instead pouring your beer out of a can at home, that long-lasting head can only be produced with the help of a plastic widget.

Simply pouring a carbonated beer, such as a lager, from the can into a glass is enough to generate a head. But this is not the case for stouts, which are infused with nitrogen bubbles, rather than carbon dioxide, in order to create their uniquely smooth texture. The small plastic widgets in each can of stout contain pressurized nitrogen, which is released once the can is opened, triggering some of the dissolved nitrogen in the beer to bubble up into a head.

Using applied mathematics, including the ideal gas equation and a fourth-order Runge-Kutta scheme with a timestep of 10-3, however, a team from the University of Limerick in Ireland recently discovered that microscopic plant fibers made of cellulose, such as cotton, can also froth up a stout.

In a paper publishing their findings earlier this month, the Limerick mathematicians conclude:

A typical pouring time for a stout beer is 30 seconds. In this time about 108 postcritical nuclei must be released. A single fibre produces one bubble every 1.28 seconds. Therefore about 4.3 × 106 fibres are needed. If each fibre occupies a surface of area λ2 then the total area that must be occupied by fibres is 8.3 × 10-4 m2.

Or, in plain English, embedding a 1 inch square of food-safe biodegradable cellulose fibers in a Guinness can would produce a perfect creamy head, doing away with the need for plastic widgets altogether. And although the technology is a long away from the shelves yet, removing plastic from our food chain is certainly something to drink to.

Images: Thumbnail (cc) by Flickr user raygunb (1) Courtesy of Michael Devereux/Mathematics Applications Consortium for Science and Industry, via Wired, still showing how pockets of air trapped in tiny cellulose fibers, each between 10 and 50 microns wide, help nitrogen and carbon dioxide bubble out; (2) the Guinness widget (cc) by Flickr user slworking2, via Wired.


October is domestic violence awareness month and when most people think of domestic violence, they imagine mostly female victims. However, abuse of men happens as well – in both heterosexual and homosexual relationships. But some are taking it upon themselves to change all that.

Keep Reading Show less

At this point most reasonable people agree that climate change is a serious problem. And while a lot of good people are working on solutions, and we're all chipping in by using fewer plastic bags, it's also helpful to understand where the leading causes of the issue stem from. The list of 20 leading emitters of carbon dioxide by The Guardian newspaper does just that.

Keep Reading Show less
The Planet
via International Labour Organization / Flickr and Michael Moore / Facebook

Before the release of "The Joker" there was a glut of stories in the media about the film's potential to incite violence.

The FBI issued a warning, saying the film may inspire violence from a group known as the Clowncels, a subgroup of the involuntarily celibate or Incel community.

Incels an online subculture who believe they are unable to attract a sexual partner. The American nonprofit Southern Poverty Law Center describes them as "part of the online male supremacist ecosystem" that is included in its list of hate groups.

Keep Reading Show less

Since normalizing relations with Communist China back in 1979, the U.S. government and its companies that do business with the country have, for the most part, turned a blind-eye to its numerous human rights abuses.

In China's Muslim-majority province of Xinjiang, it's believed that over a million members of its Uighur population are being arbitrarily imprisoned and tortured in concentration camps. Female Uighurs in detention are being given forced abortions and subjected to sexual mistreatment.

Keep Reading Show less

The vaping epidemic is like a PSA come to life. A recent outbreak of vaping-related deaths and illnesses has affected people from across 46 states. More than 800 people fell ill, and at least 17 people died from vaping. In Illinois and Wisconsin, 87% of the people who got sick said they used THC, and 71% of people also said they used products that contained nicotine. Symptoms of the illness included coughing, chest pains, shortness of breath, nausea, and fatigue. We finally might now why.

Researchers from the Mayo Clinic believe toxic chemical fumes, not the actual chemicals in the vape liquid, might be the culprit. "It seems to be some kind of direct chemical injury, similar to what one might see with exposures to toxic chemical fumes, poisonous gases and toxic agents," Dr. Brandon Larsen, a surgical pathologist at the Mayo Clinic in Arizona, said in release.

Keep Reading Show less