There are a lot of people on here who say that beer is one of the worst things they can drink for their IBS; it gives them gas cramps, gas and usually diarrhea to boot. I don't know that it causes a burning sensation, but it's definitely one of the (almost) universal IBS no-no's in terms of consumables. In fact, some people say they can tolerate hard liquor better than beer.
Have you been checked for stomach ulcers? I have heard they can feel like burning and beer is certainly acidic enough to upset them.
Next time that food bothers you like that, take note of what it was you ate. You may notice that, like the beer, the food that bothers you is acidic. That includes citrus fruits, but a lot of other fruits are acidic too, as are tomatoes (which are technically a fruit as well). So see if fruits, pizza, spaghetti, etc. items with tomato sauce set you off. Although that doesn't necessarily point to an ulcer; there are people with IBS who can't tolerate acidic foods and who don't have an ulcer, but it's something to look into. Ulcers, at least, are treatable.