We’ve all done it. You put on a pot of water to boil, add the pasta, look away for just a second, and bam. It’s boiling over and your stove-top is sizzling away in victory; the question is why? And how can you stop it from happening again?
Well, the answer is more scientific than you may think. Pasta is made out of water, flour, and sometimes egg, so it’s primarily starch and protein. When starch is heated, it continues to absorb water until it bursts. The white foam you see when you’re making pasta is just a bunch of tiny starch molecules from this mini-explosion.
This white foam layer of starch molecules makes the bubbles in the boiling water stretchy and therefore, less likely to burst. The bubbles prevent the water underneath from properly ventilating out steam and the steam then becomes super-heated and trapped. The hot steam makes the bubbles expand and pop up, making the water boil over, and leaving you with a mess to clean up on the stove.
Pasta, because of the high-starch content, is the most likely food to cause water to boil over as it requires such a large amount of water to cook. There are also several other foods that are high in starch, like dried beans and rice, that can cause water to boil over.
So how can you stop your pasta from boiling over ever again and is it even possible? Luckily, the answer is yes and there are a few ways. The first thing you can do is stop leaving a lid on your pasta pot. When you use a lid, you’re trapping heat in the pot that can cause the pasta to boil over faster than if you allow the water to ventilate.
Another way to help prevent your pasta from boiling over is by using wooden utensils or chop-sticks. By placing a wooden spoon or a few chop-sticks across the top of the pot, you can break up the bubbles that trap the steam and effectively stop the water from boiling over. Some people also recommend using a larger pot or less water, frequently stirring while cooking, and lowering the heat once the water has reached the boiling point.
You can also a small amount of butter or oil to your boiling water to help prevent boilover as they too can break up the bubbles. One thing to be careful of with this method though, is that if you add too much you can make your pasta oily and then your sauce will have a tough time sticking to it. If you’re not using sauce, though, then this does not apply.