Saliva-like, brown-tinged vomit in 1 year old

[idislikeorchids]

DS has just thrown up a 5inch x 5inch patch of brown-tinged saliva. It was just after a very big lunch (he did not throw up any of the lunch.)

He has done this a few times before - when I know he has a full stomach, but he'll vomit coloured saliva/water.

In your experience what is this?

One of mine often pukes like this when they've had a lot of liquid. So lots of milk or soup or water. And it's usually tinged with the colour of whatever they've eaten.
In hindsight maybe it's a bit of reflux or some thing.