There are three basic varieties of orange. The sweet variety are large and juicy. Their skins are difficult to remove than other types of orange. The valencia and the blood oranges are two popular types of sweet orange. Sour tasting oranges, known as bitter oranges, are mainly used in cooking or for orange liqueurs - where their essential oils and peel is often an important ingredient. Loose-skinned oranges are the sweet kind of orange that peel and segment easily.
Oranges originated in Southeast Asia - valued for their rich vitamin C content, they are grown in warm-climate areas across the world, including north america, africa, spain and portugal. The United States is the world's largest producer of oranges.
Always choose oranges than are heavy, firm and evenly shaped with smooth skins. As with lemons and limes, thicker skinned oranges will give less juice.
Oranges can be refrigerated or kept at room temperature for upto two weeks.