Orange zest adds rich flavor and fragrance to any dish and thin strips of orange rind create a delectable marmalade. Most people know the pleasure of eating orange segments, savoring the juice of an orange wedge on hot summer days, or squeezing the fruit and creating a refreshing morning beverage. The inner rind produces a fragrant oil used for anything from cooking to furniture polish. Together, these elements of the orange fruit are recognized worldwide.
Oranges contain about 50 calories for the entire fruit (including the rind) and about 40-48 calories for a glass of fresh juice, with nearly all of the calories coming from carbohydrates. Besides being loaded with vitamin C, oranges carry a multitude of other vitamins (A, thiamine, riboflavin, niacin) and minerals (calcium, phosphorus, iron, sodium, potassium).
The orange fruit contains approximately 10-14 partitioned wedges, known also as ovary cells or juice sacs, arranged in a radius around a central axis. The segments produce the pulp and closely bunched juice sacs. Orange juice is traded as a commodity on the New York Commodities Market.
Some varieties of oranges are seedless, however, most contain 2-4 seeds per segment. The seeds contain protein, good for human consumption (e.g. added with the whole fruit when juicing) as well as for cattle feed and fertilizers.
Orange oil, found in orange seeds and in glands around the outer surface of the rind, creates a highly prized fragrance as well as flavor for cooking oils. The oil also produces a fragrant base for soaps and candles, plastics and furniture polish. Crushing or squeezing the skin releases the oils.
The somewhat rough rind (epidermis) contains two layers: the aromatic, orange outer layer (epicarp) and the white, pliable inner layer (mesocarp). The outer layer creates the fragrant oils used in soaps, candles and oils (furniture polish, essential oils) as well as flavors for marmalade and juicing and can be zested for baking and cooking of all sorts, though if eaten by itself, the rind tends to be bitter. The bitter-tasting inner rind (the white portion) is usually thrown away. Used in gardens, orange rinds repel slugs, and the oil also acts as a mosquito repellent.