Your baby is too cute for words!!
I agree with MarkFromSea, Kaji does this too when he eats food too fast, drinks too fast, the water was too cold (which happens often since my house is a freezer these days) or he got into something he shouldn't have. The last one is almost like he has heartburn from the food he shouldn't be eating, but he somehow manage to steal.
We're good about putting food away, but you know how it is with these furry ones... they find it one way or another.