Yes, rinsing pasta before cooking it can remove some of the starch on the pasta's surface, and as a result, it can reduce the flavor that would otherwise be released into the cooking water. The starch in pasta helps the sauce cling to the noodles, providing a better overall taste and texture. When you rinse pasta, some of this starch gets washed away, and the pasta may become less flavorful and less able to hold the sauce.
Many pasta recipes call for cooking the pasta directly in salted boiling water without rinsing it first. This method allows the pasta to absorb some of the flavorful cooking water, enhancing its taste. Additionally, the starch released during cooking helps create a more cohesive sauce that clings better to the pasta.
Rinsing pasta is typically not recommended, especially for dishes that involve tossing the pasta with sauce after cooking. However, there may be some specific instances where rinsing could be appropriate, such as when you're making a pasta salad and want to cool the pasta quickly to stop the cooking process and prevent it from becoming too soft. In such cases, you can rinse the pasta with cold water after cooking. Otherwise, for most pasta dishes, it's best to avoid rinsing to preserve the pasta's flavor and texture.