[thedoc (OP)]

Iona Edwards-Jones asked the Naked Scientists:

I poured boiling water over a juicy red apple. 24 hours later, the apple had red droplets on the surface. How did the liquid find it's way onto the surface, and what is it?

What do you think?

[Bored chemist]

Just a  guess, but apples are mainly water. They have a waxy layer on the outside to keep the moisture in. If the boiling water damaged that layer then the juice of the apple will leak out.