Unless the recipe you are making calls for a full box of pasta, it is easy to accidentally cook more than you actually need. When cooked, un-sauced pasta sits, it gets sticky, and clumps together.
Luckily, there are a few different methods for saving cooked pasta to incorporate into dishes at a later time. You can do this with any kind of pasta, from spaghetti to penne to small shells; lasagna noodles and large shells for stuffing can be stored, but don't work as well as the smaller types of pasta. Refrigerating and freezing cooked, plain pasta or even pasta with sauce makes fixing a quick dinner later in the week (or month) a cinch.
Storing Plain Pasta in the Fridge
One of the most important factors when saving leftover cooked pasta is to package it up soon after it is made. Cooked pasta should not sit out for longer than two hours to avoid the noodles going bad before their time. Otherwise, all you need is a container with a tight-fitting lid or a zip-top bag and a little bit of oil or butter.
Place the leftover pasta in the container or bag and drizzle with a little bit of olive oil or mix with a small amount of butter, tossing well to make sure the pasta is not sticking together and is lightly coated. The type of oil is up to you. Use olive oil if you know it will complement the dish you will be preparing; if you aren't sure what you will use the pasta for then a more neutral oil like canola or vegetable is a good choice. Whether using oil or butter, a teaspoon or two (depending on the amount of pasta) should do the trick. The goal here is to keep the noodles from sticking to each other. (If you are storing freshly cooked homemade pasta, toss with a little bit of flour instead.)
If the pasta is still warm, make sure it is completely cool before you close the container. It is crucial that the container or bag is sealed very well because when exposed to air, the moisture in the cooked pasta creates the perfect environment for bacteria and mold to grow. If using a storage bag, squeeze out as much of the air as possible before sealing.
The cooked pasta should last three to five days stored in the refrigerator. After that, it will lose its flavor and the potential for mold increases.
Storing Plain Pasta in the Freezer
If you need to store the pasta for a longer period of time, you can place plain cooked pasta in the freezer. Freezer bags work well for this method, as their thin material is better than the thicker walls of storage containers. Similar to the refrigerating method, you need to toss the pasta with a little oil or butter and remove the air from the bag before sealing.
Frozen pasta can last three months or so, but for optimal freshness, you'll want to eat the noodles within two months. High water content foods like pasta have the potential for freezer burn if left too long. It is best to thaw the pasta in the refrigerator, which will take a few hours.
Storing Pasta With Sauce
You can choose to store the sauce separately from the cooked pasta or mix them together before placing it in the refrigerator or freezer. The advantage of storing them separately is that you have more flexibility later on and can use the pasta for another dish. In addition, as the pasta sits in the sauce it can become mushy over a few days. If you think you will be using the pasta in a day or so, the sauce and pasta mixed together does allow the flavors to penetrate the noodles and may make for a more delicious dish. Store in a tightly sealed container or bag with as much air removed as possible.
Using Leftover Pasta
If the recipe calls for cool or cold pasta, such as in a casserole, pasta salad, or pasta frittata, use the pasta straight from the refrigerator. If you need the noodles to be warm, you can reheat the pasta by dropping it into a pot of rapidly boiling water for 30 to 60 seconds, just until hot. Make sure not to leave the pasta in the water for longer than one minute or it will overcook. Reheat the sauce separately and then combine with the hot pasta as you would if you had made it fresh.
If you are reheating sauced pasta, it is ideal to do so in the oven at 350 F for 20 minutes and to cover the dish with aluminum foil to lock in the moisture and prevent the pasta from drying out. You can also warm up the sauced pasta on the stovetop, just be sure to stir frequently to avoid sticking. A microwave may be convenient, but it can heat unevenly and cause the dish to lose flavor.