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Orange (fruit)

Oranges, raw,
all commercial varieties
Nutritional value per 100 g (3.5 oz)
Energy 197 kJ (47 kcal)
11.75 g
Sugars 9.35 g
Dietary fiber 2.4 g
0.12 g
0.94 g
Vitamins
Vitamin A equiv.
(1%)
11 μg
Thiamine (B1)
(8%)
0.087 mg
Riboflavin (B2)
(3%)
0.04 mg
Niacin (B3)
(2%)
0.282 mg
Pantothenic acid (B5)
(5%)
0.25 mg
Vitamin B6
(5%)
0.06 mg
Folate (B9)
(8%)
30 μg
Choline
(2%)
8.4 mg
Vitamin C
(64%)
53.2 mg
Vitamin E
(1%)
0.18 mg
Minerals
Calcium
(4%)
40 mg
Iron
(1%)
0.1 mg
Magnesium
(3%)
10 mg
Manganese
(1%)
0.025 mg
Phosphorus
(2%)
14 mg
Potassium
(4%)
181 mg
Zinc
(1%)
0.07 mg
Other constituents
Water 86.75 g

Percentages are roughly approximated using US recommendations for adults.
Source: USDA Nutrient Database

The orange (specifically, the sweet orange) is the fruit of the citrus species Citrus × sinensis in the family Rutaceae.

The fruit of the Citrus × sinensis is considered a sweet orange, whereas the fruit of the Citrus × aurantium is considered a bitter orange. The sweet orange reproduces asexually (apomixis through nucellar embryony); varieties of sweet orange arise through mutations.

The orange is a hybrid, between pomelo (Citrus maxima) and mandarin (Citrus reticulata). It has genes that are ~25% pomelo and ~75% mandarin; however, it is not a simple backcrossed BC1 hybrid, but hybridized over multiple generations. The chloroplast genes, and therefore the maternal line, seem to be pomelo. The sweet orange has had its full genome sequenced. Earlier estimates of the percentage of pomelo genes varying from ~50% to 6% have been reported.

Sweet oranges were mentioned in Chinese literature in 314 BC. As of 1987, orange trees were found to be the most cultivated fruit tree in the world. Orange trees are widely grown in tropical and subtropical climates for their sweet fruit. The fruit of the orange tree can be eaten fresh, or processed for its juice or fragrant peel. As of 2012, sweet oranges accounted for approximately 70% of citrus production.

In 2013, 71.4 million metric tons of oranges were grown worldwide, production being highest in Brazil and the U.S. states of Florida and California.

All citrus trees belong to the single genus Citrus and remain almost entirely interfertile. This includes grapefruits, lemons, limes, oranges, and various other types and hybrids. As the interfertility of oranges and other citrus has produced numerous hybrids and cultivars, and bud mutations have also been selected, their taxonomy is fairly controversial, confusing or inconsistent. The fruit of any citrus tree is considered a hesperidium, a kind of modified berry; it is covered by a rind originated by a rugged thickening of the ovary wall.


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Wikipedia

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