If you’ve ever taken a swig of a bottled IPA and thought to yourself that it doesn’t taste quite like the beer you remember from the brewery or the bar, you’re probably right. Before you blame the brewery, though, you might want to consider how long that beer has been on the shelf.

According to an article by the National Center for Biotechnology Information, the iso-alpha acids in hops that are created in a boil are the major contributor to the bitter taste of beer, and also the reason that beer loses its hoppiness over time. Iso-alpha acids are very susceptible to oxidation, which leaves behind a stale taste and aroma in the place of bitterness.

“The fact that hops fade over time is widely known,” points out BJCP beer judge Patrick Dawson in his book about aging beer, Vintage Beer. In that chapter he explains that many breweries have diligently alerted their customers to the fading of hops over time. He cites Russian River Brewing Company’s Pliny The Elder Double IPA that’s plastered with messages like “Sit on Eggs. Don’t Sit on Pliny,” and “Hops Don’t Improve With Age.”

When Kieran McGill opened his first Irish pub in 1996 in the Buckhead Village community of Atlanta, the Summer Olympics hordes were descending on the city, and Guinness and fish and chips were the standard fare.

Nearly 20 years later, McGill is the CEO and President of Fado Irish Pubs, Inc. with 15 pubs stretching from Washington D.C. to Washington state, and menus featuring craft beer and cocktails and plenty of small plate offerings.

The newest Fado opened in Midtown Atlanta on St. Patricks’ Day 2015, hosting Irish Prime Minister Enda Kenny, who was Grand Marshall of Atlanta’s annual St. Patrick’s Day Parade.

But beyond that bit of tradition and a Six Nations Rugby match between Ireland and Wales on the TVs, the bustling urban location portrays a picture of the future – expressing many of the changes happening in Irish pub culture and offering a more international perspective on food and drink.

Not long ago, I sat down with McGill at Fado Midtown, where the soaring windows offer views of the cityscape, the tap handles cascade from the ceiling to the bar, and the draft list includes the likes of St. Bernardus Abt 12, Wild Heaven Invocation and Stone Smoked Porter.

Here’s a good portion of our conversation: