Pasta Water Boils Over and Plain Water Does Not — Starch Builds a Structure

Plain water boils hard for ten minutes and stays where you left it. Put the pasta in and within a minute it climbs the pot. The temperature has not changed and the boiling has not changed. What appeared is a pile of bubbles — and a pile of bubbles is a structure, with a height, holding its own weight. This video explains what makes a bubble last. A bubble is not a hole in the water, which is what you assume; it is a film, and water has high surface tension so its films break at once — in plain water nothing interrupts that sequence. Starch dissolving off the pasta collects at the surfaces of the film and holds it together, and once bubbles survive, steam collects underneath and lifts the whole pile. We check two common explanations and show both are wrong, look at why a film touching a dry surface breaks on contact, why turning the heat down is a large change for a small improvement, and why one drop of oil ends it instantly. ⏱ Chapters: 00:00 Plain water stays, pasta water climbs 01:13 A bubble is not a hole in the water 02:26 Water breaks its own films 03:40 Starch coming off the pasta 04:52 One long-lived bubble is still one bubble 06:07 A film that touches something dry 07:20 Why turning it down barely helps 08:32 One drop of oil ends it #physics #cooking #chemistry #science