Here’s a tip that TV chefs and YouTube channel owners will tell you every now and then: add a little olive oil to your pasta water. It should keep the noodles from sticking together. But Reader’s Digest explains, there’s a rational and scientific reason why that’s not really true: oil just doesn’t mix with water.
Look at oil and water on a molecular level, and you’ll see that oil molecules are repelled by water molecules—not attracted to them. That’s why oil and water won’t mix when you add one to the other. Instead, the oil will float on top of the water as it’s less dense than it.
Scientific American goes further and describes the specifics why oil and water molecules don’t mix. Water molecules are polar and carry a partial negative charge. Oil molecules are nonpolar and carry no charge. Like attracts like in chemistry, which (unlike salts and sugars) is not really the case for oil and water.
Since oil won’t mix with pasta water, it will simply float on top. This not only means that little-to-no oil makes it to the pasta noodles as they’re cooking, but that the oil will coat their surface when you strain the pasta, effectively preventing the absorption of sauce.
Adding oil to pasta water is unnecessary and can be counterproductive to your pasta dish. It might feel like you’re doing something, but the outcome is actually going to be worse.
Oil won’t prevent the pasta from sticking together. Instead, it will prevent the sauce from clinging to the pasta noodles, leading to bland pasta.
Since I discovered this fact about pasta several years ago, I stopped adding oil to my pasta water. And I haven’t had any of my noodles stick. Here’s why.
Should I Toss Pasta With Olive Oil After It’s Done Cooking?
Some TV chefs and YouTube personalities will, for some reason unknown to me, tell you to toss pasta with a little olive oil after it’s done cooking. Do not follow their advice.
Unless you’re making pasta with oil and garlic sauce (in which case you will be tossing the pasta with the sauce directly in the sauce pan), tossing pasta noodles with olive oil will prevent the tomato sauce from sticking to them.
Cook pasta in salty water until al dente, which is usually 2-3 minutes before the cooking time. Toss the pasta with the sauce, ideally in the sauce pan and right after the sauce is done cooking, for 1-2 minutes, then serve.
Leave olive oil only for pasta aglio e olio and pasta salads. It’s going to prevent you from making good pasta, not help you, for all other recipes.
How to Keep Pasta Noodles From Sticking Together
So what should you be doing to keep pasta noodles from sticking together? Three things: buy quality pasta, use a large pot of water, stir the noodles in the beginning and don’t cook them too much.
Buy dry pasta made from 100% semolina. Semolina is a hard wheat flour that gives pasta flavor, making your pasta dish tastier, and firmness, helping the noodles hold up in the cooking process. Check out my list of the best Italian pasta brands you can find at grocery stores.
Use a large pot of water. As a rule of thumb, use 4 quarts of water for every 1 pound of pasta. Pasta noodles need the right amount of water to cook correctly, especially as starches will start to dissolve in the water and make it thicker and cloudier.
Add the pasta noodles to a rolling boil and stir them in the beginning. Bring the large pot of water to a rolling boil before adding in the pasta noodles. A rolling boil happens at medium-high to high heat and is when the water bubbles are rolling vigorously. Stir the noodles occasionally in the first 1-2 minutes of cooking.
Don’t overcook your pasta. Perhaps the biggest reason why Americans see their pasta sticking is that they are cooking it too much. Pasta should only be cooked until it becomes soft, but it still firm to the bite and gives you some resistance when you bite into it. This is what Italian chefs call “al dente” or “to the tooth.” Learn how in my post, This Is How to Tell When Pasta Is Cooked.
The formula is simple: Quality Pasta + 4 Quarts Water per 1 Pound Noodles + Cook In Rolling Boil and Stir Only Initially + Cook Al Dente = Great Pasta.
Should You Save Pasta Water?
Using a little bit of pasta water in your pasta sauce is my secret for making Italian restaurant-grade pasta dishes.
Don’t throw pasta water away when boiling pasta noodles. The cloudy, salty, and starchy liquid can help you elevate an okay plate of pasta into the pasta dish of your dreams.
Pasta water’s cloudiness comes from the starches contained in it. Pasta noodles consist of gluten, a mix of two wheat proteins that give pasta its elasticity, and starch, a carbohydrate that gives pasta water its distinct white color.
When you’re done boiling the noodles, save a cup of the pasta water. Then add 2-3 tablespoons of it when you’re cooking the pasta sauce in the sauce pan (no matter if the sauce is garlic and oil, canned tomatoes, or cheese based).
The starches contained in the pasta water are going to dissolve in the sauce—helping it cling to the pasta noodles when you toss them with it.
Here’s a neat trick I learned from someone in a cooking forum several years ago:
“The water that you used to cook in has a lot of starch in it from the pasta. When you go to drain your pasta, you can reserve a small bit of the water you cooked your pasta in. When the time comes to serve, simply pour and stir the reserved water over the sitting pasta. Not only does this help prevent stickiness, but it also warms your pasta again after sitting for 5-6 minutes, or however long you wait to serve your meal.”Jacob R. (Cooking on Stack Exchange)
Try this out and let me know how it turned out in the comments below.
Adding olive oil (or any other oil or fat) to your pasta water won’t keep the noodles from sticking together. In fact, it’s going to do more harm than good. The oil will coat the pasta and keep the sauce from clinging to it when you toss the noodles with it.
Instead of adding olive oil to pasta water, use a large pot with enough water (4 quarts water for every 1 pound of pasta), stir the noodles in the first 1-2 minutes when you add them in, and boil the noodles just enough, until they’re cooked al dente and still firm to the bite.