“I always recommend pouring beer into a glass. Why? One of the bi-products of fermentation in beer is carbon dioxide. In beer, carbon dioxide delivers the aromas of the hops, yeast and malt from the glass to your nose; it creates the tingle on your tongue, and is the principal backbone for beer’s signature foam top.”
Unfortunately, all of that CO2 doesn’t just disappear- it has got to wind up somewhere. If you’re eating some good grub to go with that beer, your next bite will essentially act like a detonator that releases the gas from the beer inside of your stomach, contributing to that awful bloating feeling.