The Internet is flooded with articles and videos advising you to put the oil in the pasta cooking water For don’t let it attack. He is one of those false myths handed down from grandmothers, according to whom the oil slippery it wouldn’t make the pasta stick. It’s all false: adding oil to the water to prevent the pasta from sticking is useless. Oil and water have density different, the first one floats and therefore cannot “divide” the dough. The advice is always to use plenty of water and a large pan so as to “dilute” the starch but we will surprise you: adding oil to the cooking water actually has a very specific “benefit”.
The oil is used to prevent foaming
The oil prevents foam from forming, that annoying phenomenon that causes the water to overflow from the pan when you cook pasta with the lid on. The foam is formed because thestarch of the pasta creates a “cork” on the surface of the liquid which does not allow all the vapor to escape. This accumulates and so at a certain point the starch “cap” salt until the water comes out.
Why does oil stop water from foaming? We asked him Alberto Colellafamous food blogger and esteemed chemist: “Most oils act as antifoamwe use them even in the laboratory”. Antifoam is a silicone-based compound used forculling of foam in water-based systems.
In practice we have to imagine the oil divided in two”souls“: one adore substances similar to water, the other he hates. “In graphics – continues Colella – we can see the little orange head who loves water and tail who hates her. Like dissolves like: the heads join together with what makes the foam because there is an affinity with the air-liquid surface, the tails join together and the foamy structure disappears”. The chemist also gives us another example linked to household world: “The same concept applies to chemical agents detergents: they bind to dirt and remove stains with the same functioning as oil in water which prevents foam”.
Adding oil to the cooking water is therefore useless for anything except the foam. To avoid this inconvenience actually a few small precautions are enough: always use plenty of salted water (1 liter for every 100 grams of pasta) and mix frequently during cooking. If you do these two things you can also avoid adding oil.
