I ate a dinner last night and in the morning nine hours later, i was burping up bits of it. what causes this delayed digestion?

Indigestion: If this is a one time problem that you have noticed, it may be related to food intolerance for a specific food or perhaps a food poisoning. On the other hand, if you have this everyday, you need to get it evaluated by a gastroenterologist to make sure you don't have an inflammation in the lining of the stomach- gastritis or other conditions that make your stomach to move slower than usual.