Wooden Spoon Over Boiling Poot

• Put a wooden Spoon across a boiling pot of water or milk or any thing to keep it from boiling over.
• The most popularly held belief is that the wooden spoon prevents heat from building up too much at the centre of the pot, thus preventing the liquid from boiling too high but this is not true.
• First, bubbles are unstable forms. When something hydrophobic (i.e. unable to absorb water) punctures the surface of a bubble, it subsides.
• A dry wooden spoon destabilises the bubbles when they come into contact with its water-repelling surface. This makes the boiling water retreat.
• Second, bubbles and foam created from boiling water are filled with steam (aka water in the form of a gas or vapour). If the bubble touches something whose temperature is below 100°C (212°F), the steam will condense (change back into a liquid) and break the surface of the bubble.
• At some point, your wooden spoon will heat up and the water will rise no matter what. And don't try using a metal spoon in lieu of a wooden one metals conduct heat much more quickly.
• One good quick fix: you can blow on the surface of a boiling pot and the foam will retreat, since your breath is most likely well below 100°C, temperature-wise.