There are several things that can cause gas but remember each person is different and other foods may cause problems that are not listed, so keep a diet history and watch for trends. You will be able to look back and see that every time you eat/drink .... "I get more gas".
If you have this problem, Simethacone will help relieve the gas and discomfort and this medicine comes in many brand names (ie Gas-X)
Another way to relieve gas is to drink a hot liquid and then lie over your abdomen on two pillows. It will help push the gas out.