Greetings I would drink water instead unless I had just finished a meal. Water dilutes stomach acid and makes it easier and is a healthier way to eliminate heartburn. It can be taken in between meals up to 20 minutes before a meal and some little time after the meal. At least 6.25 cups water for every 100 pounds body weight needs to be taken daily at minimum for most people and usually the real requirement is more so water should be freely taken.
Some things that might cause the heartburn include things with vinegar in them such as ketchup, salad dressing, mayonnaise, mustard, food additives, fruits, vegetables, and baked or cooked grain foods could be used as tolerated. Nut foods should be used to a small extent with thorough chewing after the stomach is mostly recovered as they are harder to digest. I would try to eat the meals 5 hours apart on a schedule and make the last meal very light. I would not snack to allow the stomach rest between meals. I would write a daily diary of foods used and whether or not there were symptoms and if so which ones.