Bloating: what happens?

I'm curious as to what exactly happens when we eat something that triggers a Candida assault. I've been following an anti-Candida regime, successfully I thought. Bloating had gone and I was feeling better. Then I ate something which didn't agree with me and within an hour, I was feeling dreadful. Huge bloated stomach and very uncomfortable. I thought I had killed most of them off but clearly not. What happens in the bowel to create this ball of trapped air?