When the Hulk is first approached in The Avengers movie the following exchange happens1:
Natasha Romanoff: Doctor, we're facing a potential global catastrophe.
Bruce Banner: Well, those I actively try to avoid.
Natasha Romanoff: This is the Tesseract. [she shows him a photo of the Tesseract on her cell phone]
Natasha Romanoff: It has the potential energy to wipe out the planet.
Bruce Banner: What does Fury want me to do? Swallow it?
Natasha Romanoff: Well, he wants you to find it. It's been taken. It omits a gamma signature that's too weak for us to trace. There's no one that knows gamma radiation like you do. If there was, that's where I'd be.
Bruce Banner: So Fury isn't after the monster?
What happens if the Hulk swallows the Tesseract(the energy source cube from The Avengers movie) and then morphs back to human form?
My idea: Hulk wont need to pull ambient-gamma radiation to transform again. Will have it inside. Would need to eat an alien to help digesting.