More than any other fruit, the orange is associated with and valued for its vitamin C content. It is, in fact, the primary source of vitamin C for the majority of Americans. But oranges have more to offer nutritionally than just this one nutrient. A small orange (about five ounces) contains generous levels of folate (folic acid), potassium, and thiamin, as well as some calcium and magnesium. And compared to other citrus fruits, oranges have a broader range of uses: They can be added to various cooked or cold dishes, eaten as snacks, or squeezed for their delicious juice.Americans consume most of their oranges in the form of juice, which provides 140% of the current suggested daily intake of vitamin C. However, if you choose to eat a whole orange instead of drinking a glass of juice, you’ll get about the same amount of vitamin C with the added benefit of more than 3 grams of dietary fiber.

Orange trees are semitropical non-deciduous trees and, like other citrus fruits, they probably originated in Southeast Asia. We take oranges for granted now (they are the third most popular fruit in the U.S., right behind bananas and apples), but at one time they were expensive and only rarely available in cooler climates. Columbus brought orange seeds and seedlings with him to the New World, and by the 1820s, when Florida became a U.S. territory, there were thriving orange groves in St. Augustine. By 1910, Florida was on its way to its current status as the number-one citrus-growing state.

In the Forties, scientists developed frozen orange-juice concentrate which led to oranges becoming the main fruit crop in the United States. Today, Florida produces about 70% of the country’s oranges, and about 90% of the crop is processed into juice. California and Arizona are the other two states where oranges are extensively cultivated. Their oranges, however, have thicker skins than Florida fruits, a characteristic that helps to protect them against the drier climates of the West. They are also more prized as eating oranges.

Varieties : There are two types of oranges, sweet and sour. Only sweet oranges are grown commercially in the United States, and those you are most likely to find include:

Hamlin: One of the earliest maturing oranges, Hamlins are grown primarily in Florida. Although they are practically seedless, their flesh is rather pulpy so they are better for juicing than for eating. Small in size, Hamlins have a very thin skin. Season: October through December.

Temperature and storage time affects the percent of vitamin C content of orange fruits and orange juice.Different varieties of oranges also have different levels of vitamin C.

The mid-season variety, Pineapple Orange had the highest levels, followed by the main early-season variety, Hamlin Orange.

The late-season Valencia Orange had the lowest vitamin C content. Additionally, it was found that the longer the Valencia Orange fruit stayed on the tree, the lower the vitamin C level.

Research also found that in orange juice containers, vitamin C loss was due to oxidation by a residual air layer trapped within the container during processing. The loss was faster in the first 2 weeks and was more evident at higher storage temperatures. Therefore, orange juice must be kept cool to prevent vitamin C degradation as it is excellerated at high storage temperatures.