[nudephil (OP)]

A question from Anthony:

When pasta or rice is added to boiling water, there is a sudden surge of the boiling water to the point where the pot boils over with bubbles. Why is this?

Penne for your thoughts? What's the answer?

[alancalverd]

Adding any granular material can nucleate bubbles in superheated water. If the added material contains starch or gluten, the bubbles can form a strong mat instead of bursting at the surface, so the next group of bubbles pushes the mat upwards and the pan boils over. Same with milk and many other substances.   

[nudephil (OP)]

Thanks for this answer Alan. Your contribution was included when we answered the question on our most recent show "Code Making and Breaking" and on the QotW podcast feed.