Spaghetti is a long, thin, cylindrical, solid pasta. Like other pasta, spaghetti is made of milled wheat and water. Italian spaghetti is made from durum wheat semolina, but elsewhere it may be made with other kinds of flour.
Originally spaghetti was notably long, but shorter lengths gained in popularity during the latter half of the 20th century and now spaghetti is most commonly available in 25–30 cm (10–12 in) lengths.
Pasta provides carbohydrate, along with some protein, iron, dietary fiber, potassium and B vitamins. Pasta prepared with whole wheat grain provides more dietary fiber than that prepared with deformed flour.
At its simplest, spaghetti can be formed using no more than a rolling pin and a knife. A home pasta machine simplifies the rolling, and makes the cutting more uniform. Fresh spaghetti would normally be cooked within hours of being formed. Commercial versions of ‘fresh’ spaghetti are manufactured.
The bulk of dried spaghetti is produced in factories using auger extruders. While essentially simple, the process requires attention to detail to ensure that the mixing and kneading of the ingredients produces a homogeneous mix, without air bubbles. The forming dies have to be water cooled to prevent spoiling of the pasta by overheating. Drying of the newly formed spaghetti has to be carefully controlled to prevent strands sticking together, and to leave it with sufficient moisture so that it is not too brittle. Packaging for protection and display has developed from paper wrapping to plastic bags and boxes.