The thickness of the peel is not a good guide, since it varies according to variety as well as growing region.

Keep at room temperature for several days. To keep longer, refrigerate in a plastic bag or covered in the crisper of the refrigerator.
Some oranges, such as navels, tend to become bitter once they are cut and exposed to the air for a while.
Freezing is not recommended, except for the zest and the peels once the juice has been squeezed out.

Oranges are found in many dishes, whether as "supremes," or in zest or juice. To sweeten a mixture or to enliven a sauce you need only add some oranges.

Always cut oranges into "supremes" when using them in a recipe: cut lengthwise along the flesh of each segment to remove it from the membranes surrounding it. To heighten the flavor, soak them in orange juice or mist with orange flower water.

There are, of course, classics like duck à l'orange, frozen oranges filled with Italian meringue, orange sorbets and ice creams…

• Use orange juice instead of lemon juice or vinegar in a vinaigrette.
• Chilled orange avocado soup - make as you would a vichyssoise but replace the leeks with avocado and add some orange juice and a few cumin seeds at the very end.
• Sauce Maltaise - a hollandaise to which you add the zest and juice of blood oranges: an excellent accompaniment to asparagus.
• Simmer oranges with broccoli, carrots, chicken broth and shallots: thicken the cooking liquid with starch.
• Use in salsa to accompany chicken breasts: oranges, red onion, cilantro, garlic and chili pepper.
• Orange salad with cabbage, water chestnuts, green onions, Chinese noodles and sweet-sour dressing.
• Wild rice cooked in chicken broth with red onion, sweet pepper, sage and orange zest.

Spain
Macédoine of oranges and black olives - supremes of table oranges, sliced pitted black olives, toasted almonds, Sherry vinegar, virgin olive oil and orange flower honey.

Portugal
Bread pudding with orange marmalade - a change from the ordinary: make an orange marmalade, mix with hot milk and eggs, pour over stale bread and bake in the oven.