should be thin, smooth, and fine-grained. The skin on navel oranges, the large seedless “eat-
ing orange,” is thicker; it comes off easily when you peel the orange.*
Storing This Food
Refrigerate oranges if you plan to keep them for longer than a week or two.
Refrigerate fresh orange juice in a tightly closed glass bottle. The key to preserving
vitamin C is to protect the juice from heat and air (which might seep in through plastic
bottles). The juice should fill the bottle as high as possible, so that there is very little space
at the top for oxygen to gather. Stored this way, the juice may hold its vitamin C for two
weeks. Frozen juice should be kept frozen until you are ready to use it; once reconstituted, it
should be handled like fresh juice.
Preparing This Food
Oranges may be waxed to prevent moisture loss and protect them in shipping. If you plan to
grate orange rind and use it for flavoring, scrub the orange first to remove the wax. Do not
grate deeper than the colored part of the skin; if you hit the white underneath, you will be
getting bitter-tasting components in with the rind.
Orange peel contains volatile fragrant oils whose molecules are liberated when the
skin is torn and its cell walls ruptured. These molecules are also more fragrant at room tem-
perature than when cold. “Eating oranges” have a much truer aroma and flavor if you let them
come to room temperature before peeling and serving.
What Happens When You Cook This Food
Heat destroys the vitamin C but not the flavoring oils in an orange. When oranges or orange
peel are cooked, they add flavor but no noticeable amounts of vitamin C.
How Other Kinds of Processing Affect This Food
Commercially prepared juices. How well a commercial orange juice holds its vitamin C
depends on how it is prepared, stored, and packaged. Sealed cans of orange juice stored in
- Oranges look most appetizing when they are a deep, vibrant orange, but on the tree a mature orange
is usually green-skinned. It will turn orange only if it is chilled and the cold temperature destroys
green chlorophyll pigments, allowing the yellow carotenoids underneath to show through. In a warm
climate, like the Mideast, oranges are always green, but in the United States oranges are green only if
they are picked in the fall before the first cold snap or if they are picked early in the spring when the
tree is flooded with chlorophyll to nourish the coming new growth. Green oranges will also change
color if they are exposed to ethylene gas which, like cold, breaks down the chlorophyll in the orange’s
skin. (Ethylene is a natural chemical found in all fruits that encourages them to ripen.) Oranges may
also be dyed with food coloring.
Oranges