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The Science of Green Beer

Connor McKoy
Connor McKoy
March 17, 2021

Annually on March 17th, "the Irish and the Irish-at-heart across the globe observe St. Patrick’s Day,” as the popular saying goes. It was originally a day of religious feasts for the patron saint of Ireland, but today it is an international celebration of Irish culture—complete with parades, dancing, special foods and a whole lot of green. Including green beer!

Best Green Beer Recipe - How to Make Green Beer
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According to the National Retail Federation, in the pre-pandemic days around 37 million Americans celebrated St. Patrick’s Day at a bar or restaurant, this year about half of all Americans plan to mark the occasion somehow—whether it’s a small celebration at home or attending a more intimate gathering.

In 2015, WalletHub reported "13 million pints of Guinness beer were consumed on St. Patrick’s Day."

Even though a lot of alcohol is consumed during this holiday, most are unaware how it is made. Alcohol production, in fact, is one of the most basic applications of industrial biotechnology.

Beer is made from water, a starch source such as barley, brewer’s yeast, and a flavoring such as hops. The starch in the barley must be converted to sugar by enzymes (which are activated when the barley is malted) then fermented (the brewer’s yeast metabolizes the sugars to produce alcohol and carbon dioxide). Enzymes and microbes are two common tools used in industrial biotechnology.

You may be asking yourself: if biotech can help produce beer, can it improve it as well? The answer is YES! The biotech industry came up with a solution for providing green beer without the use of green dye #3. For instance, one research company, Leavandary, produces designer yeast for craft brewers. Leavendary, located in Huntsville, Alabama, modified one of its strains to create green beer as a demonstration project for St. Patrick’s Day.

So, while you celebrate St. Patrick's Day with a mug of beer remember to toast industrial biotechnology and know that without science we may not have beer.