Well, probably depends on the predator. Realistic preds, you could be in there for hours, despite not being conscious for most of the digestion, cause you don't have air. Or it could be a toonier or more powerful predator that can power-churn you, or make you disappear with a big glorp noise!

Antacids help prolong things, too. I'd imagine there's some pills that might even give more air. So that'd prolong the squirming, if you're wanting to have prey move for longer!

Also, a taur would be a huge meal, so...