Steam is rising as a large pot of water comes to a boil. This scene is taking place right now in kitchens all over the globe, and an under appreciated life force is being created—pasta water. 

Americans consume over 6 billion pounds of pasta and noodles annually, or about 16 million pounds per day. Each pound of that pasta/noodle product cooks in a gallon of water with 1 to 2 tablespoons of salt added, so that is 16 million gallons of water heated up and mostly poured down the drain at the end of cooking. “Mostly” is the keyword here, since cooks in the know will save some of that water and use it to make some magic. 

Pasta water has many names. In Italy, it is “l’acqua di cottura della pasta” or “the cooking water of the pasta.” Chefs and home cooks in the know call it “liquid gold,” and Martha Stewart, the doyenne of the domestic art of cooking, calls it a “magic elixir.”

The water used to boil pasta and noodles is salty and cloudy. Fresh and frozen noodles are often dusted with cornstarch to prevent clumping, so these products add extra starch to the cooking water, in addition to the starch in the noodle itself that leaches out and absorbs water as gelatinization occurs.

The benefit of saving and using some of this cloudy, salty water is that it helps emulsify sauces and adds a silky texture to your finished dish. The cooking water also helps the sauce adhere to the noodles, especially when using an oil-based sauce like pesto. The starch in the cooking water allows the immiscible pesto to lightly coat each strand of noodle or pasta, improving the consistency, flavor, and texture of the finished dish.  

According to Food & Wine, “A little bit of pasta water is the key to making smooth, restaurant-level sauces. Some of the most classic Italian pasta dishes, like cacio e pepe and carbonara, depend on the starchy binding power of pasta water to make the sauce.” Blue Apron, the meal kit company that debuted in 2012, at the dawn, in America, of this type of home service, recommends adding a bit of pasta water “to create luxurious sauces for meals like Pasta al Limone.” Bon Appetit concurs that “pasta water can turn good pasta into the silky, saucy pasta of your dreams.”

How to Make Pasta/Noodle Water:

1. Use cold tap water to fill your 5-6 quart pot. Using hot water doesn’t speed up the process and can be hazardous, as it can leach contaminants from old pipes or the water heater. 
2. After the water comes to a boil, add 1 to 2 tablespoons of Kosher salt.
3. Add the pasta/noodles to the boiling salted water.
4. Gently agitate with a long pair of tongs, a pasta fork, or a wooden spoon to separate the product at the start of cooking to prevent clumping. 
5.  Cook the pasta/noodles according to the package instructions, or slightly less to achieve “al dente” perfection. 
6. Extract the pasta/noodles with tongs or a spider and save some of the water to add to your sauce and finish your dish. You can use a glass Pyrex measuring cup or even a coffee mug to do this safely. Reserve 1-2 cups of the liquid gold for your sauce and for reheating leftovers.
7. The remaining pasta water can be used in baking or in making a soup, like a minestrone, but remember that it is already salty. The starch in the water will lend the soup a silky texture. 

The website Serious Eats does a deep dive into pasta water and describes the best way to sauce your pasta. If you want a small education, check out the many variables they describe. The recipe for a lighter version of Fettuccini Alfredo also makes excellent use of the pasta water

Now that you are sold on the benefits of saving and using the cooking water, what happens if it gets accidentally thrown out?

If a well-meaning assistant discards your pasta water, you can make a cornstarch slurry to substitute. Add ½ teaspoon of cornstarch and ½ teaspoon of Kosher salt to a cup of water, stirring until dissolved. Voila--your workaround!

The water used to cook pasta and noodles is a valuable commodity that can lend your home-cooked meals a cachet reserved for fine-dining experiences. The cloudy water serves as an emulsifier, binding the fat to the liquid in your sauce. This is very evident in a preparation like Pasta Carbonara, where the fat from the rendered pancetta or bacon combines with beaten egg and grated cheese to form a sauce when a bit of the pasta/noodle water is added to the finished dish. It makes the dish silky smooth, with the disparate sauce ingredients clinging to each strand, inviting only a light dusting of additional freshly grated Parmesan and a finish of freshly ground black pepper to create a sublime mouthful. 

Should any of that Carbonara be left over, the pasta water can be added to help in reheating and prevent toughening and drying out the remaining pasta. 

In addition to the starch and salt in the pasta/noodle water, there are trace minerals—copper, selenium, and B vitamins—and the water can be used in baking, making soup, and cooking beans. Just remember that it is already salty. 

Pasta water is an effective tool to add to your culinary wheelhouse. The starch content serves as a binder, and the salt content adds flavor. It will make your pasta and noodle dishes taste like they just came out of a professional kitchen. The pasta water hack has got your back, says Grandma.