Oil added to pasta cooking water ends up almost all going down the drain. There are better ways to minimize sticking.
Why Isn't Oil in the Pasta Cooking Water a Good Idea?
Oil is slippery , right, so you think putting oil in the water would work. But almost all the oil ends up going down the drain when you drain the pasta. While the little bit of remaining oil will help a bit to reduce stickiness, this technique is a real waste of oil and there are better ways.
Better Ways to Prevent Sticking Pasta
So how can you reduce sticking? Tossing the pasta with a little oil just after draining works much better. Or do as the Italians do, which is to mix the pasta with some sauce right away after you drain it. This has the added advantage of letting the flavors meld.
Other ways to reduce sticking problems include buying high quality pasta (which sticks less than the cheap stuff), by not overcooking the pasta, and by making sure you are boiling it in enough water, and by salting the water. Also, stirring the pasta for 10-20 seconds right after adding it to the boiling water makes stickiness less of a problem. If you are cooking the pasta for later use, or for use in a cold dish, try rinsing with cold water right after draining.
