General info about Fruit
The sour orange is native to southeastern Asia. Natives of the South Sea Islands, especially Fiji, Samoa, and Guam, believe the tree to have been brought to their shores in prehistoric times. Arabs are thought to have carried it to Arabia in the 9th Century. It was reported to be growing in Sicily in 1002 A.D., and it was cultivated around Seville, Spain, at the end of the 12th Century. For 500 years, it was the only orange in Europe and it
was the first orange to reach the New World. It was naturalized in Mexico by 1568 and in Brazil by 1587, and not long after it was running wild in the Cape Verde Islands, Bermuda, Jamaica, Puerto Rico and Barbados. Sir Walter Raleigh took sour orange seeds to England; they were planted in Surrey and the trees began bearing regular crops in 1595, but were killed by cold in 1739.
Spaniards introduced the sour orange into St. Augustine, Florida. It was quickly adopted by the early settlers and local Indians and, by 1763, sour oranges were being exported from St. Augustine to England. Sour orange trees can still be found in Everglades hammocks on the sites of former Indian dwellings. The first sweet orange budwood was grafted onto sour orange trees in pioneer dooryards and, from that time on, the sour orange became more widely grown as a rootstock in all citrus-producing areas of the world than for its fruit or other features. Today, the sour orange is found growing wild even in southern Georgia and from Mexico to Argentina.
It is grown in orchards or groves only in the Orient and the various other parts of the world where its special products are of commercial importance, including southern Europe and offshore islands, North Africa, the Middle East, Madras, India, West Tropical Africa, Haiti, the Dominican Republic, Brazil and Paraguay.
How to choose a ripe and fresh Fruit
The fruit is round, oblate or oblong-oval, 2 3/4 to 3 1/8 in (7-8 cm) wide, rough-surfaced, with a fairly thick, aromatic, bitter peel becoming bright reddish-orange on maturity and having minute, sunken oil glands. There are 10 to 12 segments with bitter walls containing strongly acid pulp and from a few to numerous seeds. The center becomes hollow when the fruit is full-grown.
Ways to prepare and serve the Fruit
Edible Parts: Fruit.
Edible Uses: Condiment; Oil.
Fruit - raw or cooked. Very bitter. It is used in making marmalade and other preserves. The fruit is about 5 - 7cm in diameter. The rind of the fruit is often used as a flavouring in cakes etc. Used in ‘bouquet garni’. An oil obtained from the seeds contains linolenic acid and is becoming more widely used as a food because of its ability to reduce levels of cholesterol in the blood. The flowers are used for scenting tea. An essential oil from the dried peel of immature fruits is used as a food flavouring.
Health Benefits and Warnings of eating Fruit
Antibacterial; Antiemetic; Antifungal; Antispasmodic; Antitussive; Aromatherapy; Carminative; Contraceptive; Diaphoretic; Digestive; Miscellany; Sedative; Stimulant; Stomachic; Tonic.
Citrus species contain a wide range of active ingredients and research is still underway in finding uses for them. They are rich in vitamin C, flavonoids, acids and volatile oils. They also contain coumarins such as bergapten which sensitizes the skin to sunlight. Bergapten is sometimes added to tanning preparations since it promotes pigmentation in the skin, though it can cause dermatitis or allergic responses in some people. Some of the plants more recent applications are as sources of anti-oxidants and chemical exfoliants in specialized cosmetics. The plants also contain umbelliferone, which is antifungal, as well as essential oils that are antifungal and antibacterial. They also contain the pyrone citrantin, which shows antifertility activity and was once used as a component of contraceptives. Both the leaves and the flowers are antispasmodic, digestive and sedative. An infusion is used in the treatment of stomach problems, sluggish digestion etc. The fruit is antiemetic, antitussive, carminative, diaphoretic, digestive and expectorant.The immature fruit can be used (called Zhi Shi in China) or the mature fruit with seeds and endocarp removed (called Zhi Ke). The immature fruit has a stronger action. They are used in the treatment of dyspepsia, constipation, abdominal distension, stuffy sensation in the chest, prolapse of the uterus, rectum and stomach. The fruit peel is bitter, digestive and stomachic. The seed and the pericarp are used in the treatment of anorexia, chest pains, colds, coughs etc. The essential oil is used in aromatherapy. Its keyword is ‘Radiance’. It is used in treating depression, tension and skin problems.
Essential; Hedge; Oil; Repellent; Rootstock.
This species is much used as a rootstock for the sweet orange, C. sinensis, because of its disease resistance and greater hardiness. Grown as a hedging plant in N. America. A semi-drying oil obtained from the seed is used in soap making. Essential oils obtained from the peel, petals and leaves are used as a food flavouring and also in perfumery and medicines. The oil from the flowers is called ‘Neroli oil’ - yields are very low from this species and so it is often adulterated with inferior oils. The oil from the leaves and young shoots is called ‘petit-grain’ - 400 kilos of plant material yield about 1 kilo of oil. This is also often adulterated with inferior products. Neroli oil, mixed with vaseline, is used in India as a preventative against leeches.
There are various well-established forms of the sour orange. In the period 1818-1822, 23 varieties were described and illustrated in Europe. A prominent subspecies is the Bergamot orange, C. aurantium, var. bergamia Wight & Arn., grown in the Mediterranean area since the 16th Century but commercially only in Italy. Trees grown in California and Florida under this name are actually the ‘Bouquet’ variety of sour orange (see below). The flowers of the Bergamot are small, sweetly fragrant; the fruits round or pear-shaped, with strongly aromatic peel and acid pulp.
The myrtle-leaved orange (C. aurantium, var. myrtifolia), is a compact shrub or tree with small leaves and no thorns. It was found as a bud mutation on trunks of old sour orange trees in Florida. It is propagated and grown only on the French and Italian Riviera for its small fruits which are preserved in brine and exported for candying.
Apart from these special types, there are several groups of sour oranges, within which there are placed certain cultivars:
- Normal group (large, seedy fruits)
‘African’, ‘Brazilian’, ‘Rubidoux’, ‘Standard’, ‘Oklawaha’ and ‘Trabut’. ‘Oklawaha’ originated in the United States. It has large fruits rich in pectin and is prized for marmalade.
- Aberrant group
‘Daidai’, or ‘Taitai’, popular in Japan and China. Its fruits are large with very thick peel, very acid pulp, and many seeds. The tree is somewhat dwarf and almost thornless; immune to citrus canker in the Philippines. It is prized for its flower buds which are dried and mixed with tea for their scent.
‘Goleta’ has medium-large fruits with juicy, medium-sour pulp and very few seeds. The tree is of medium size and almost thornless.
‘Bouquet’ has small, deep-orange fruits, acid, with few seeds. The tree is less than 10 ft (3 in) high and is grown as an ornamental.
- Bittersweet group includes any sweet-acid forms of the sour orange introduced by Spaniards and formerly found growing in the Indian River region of Florida. These oranges are often seen in a naturalized state in the West Indies. The peel is orange-red, the pulp is darker in hue than that of the normal sour orange.
‘Paraguay’ was introduced from Paraguay in 1911. The fruit is of medium size, with sweet pulp, moderately seedy. The tree is large, thorny and hardy.
Among other forms of sour orange, there is in India a type called ‘Karna’, ‘Khatta’ or ‘Id Nimbu’, identified as C. aurantium var. khatta (or C. karna Raf.) but suspected of being a hybrid of sour orange and lemon. The fruits are typical sour oranges but the flowers are red-tinted like those of the lemon.
Two cultivars are grown as rootstocks for the sweet orange in China:
‘Vermilion Globe’ has oblate fruits containing 30 to 40 seeds. The tree has long, narrow, pointed leaves.
‘Leather-head’ has small, oblate, rough fruits with 20 seeds. The tree has elliptic, blunt leaves.
Cultivars grown especially for the production of Neroli oil in France and elsewhere, have flowers in large, more concentrated clusters than the ordinary types of sour orange. One of these, ‘Riche Défouille’, has unusual, wingless leaves.
Recipes made mainly with this Fruit
The normal types of sour orange are usually too sour to be enjoyed out-of-hand. In Mexico, however, sour oranges are cut in half, salted, coated with a paste of hot chili peppers, and eaten.
The greatest use of sour oranges as food is in the form of marmalade and for this purpose they have no equal. The fruits are largely exported to England and Scotland for making marmalade. Sour oranges are used primarily for marmalade in South Africa.
The juice is valued for ade and as a flavoring on fish and, in Spain, on meat during cooking. In Yucatan, it is employed like vinegar. In Egypt and elsewhere, it has been fermented to make wine.
“Bitter orange oil”, expressed from the peel, is in demand for flavoring candy, ice cream, baked goods, gelatins and puddings, chewing gum, soft drinks, liqueurs and pharmaceutical products, especially if the water-or alcohol-insoluble terpenes and sesquiterpenes are removed. The oil is produced in Sicily, Spain, West Africa, the West Indies, Brazil, Mexico and Taiwan.
The essential oil derived from the dried peel of immature fruit, particularly from the selected types -‘Jacmel’ in Jamaica and the much more aromatic ‘Curacao orange’ (var. curassaviensis)-gives a distinctive flavor to certain liqueurs.
“Neroli oil”, or “Neroli Bigarade Oil”, distilled from the flowers of the sour orange, has limited use in flavoring candy, soft-drinks and liqueurs, ice cream, baked goods and chewing gum.
‘Petitgrain oil’, without terpenes, is used to enhance the fruit flavors (peach, apricot, gooseberry, black currant, etc.) in food products, candy, ginger ale, and various condiments.
‘Orange leaf absolute’ enters into soft-drinks, ice cream, baked goods and candy.
The ripe peel of the sour orange contains 2.4 to 2.8%, and the green peel up to 14%, neohesperidin dihydrochalcone which is 20 times sweeter than saccharin and 200 times sweeter than cyclamate. Potential use as a sweetener may be hampered by the limited supply of peel.