Citrus Pages / Sour oranges

Finnish

Sour orange
Citrus aurantium

	History Uses Taste Varieties Names Sour orange Common sour orange Seville orange Bittersweet orange Leather-head sour orange Perfumery varieties Myrtle-leaved orange Chinotto Daidai sour oranges Tosu orange Bergamot
Sour orange, Citrus aurantium © CCPP Citrus Clonal Protection Program

History

The sour orange is thought to have originated in the northwestern parts of India and the neighbouring southeastern parts of China and northern Burma. Its cultivation spread slowly and reached the eastern Mediterranean at the beginning of the Christian era. Arab conquerors brought the sour orange to southern Europe and it is known to have grown in Sicily in 1002 A.D. and in southern Spain, around Seville, at the end of the 12th century. All through the Middle Ages in parts of central and southern Europe the sour orange was the only known citrus fruit and it was considered an important medicinal plant. The fruit was used as a spice and to make marmalade. The flowers were used as a scent. The sour orange was among the first fruit introduced to the New World. It soon naturalized in Florida and Paraguay where the biggest plantations emerged. The sweet orange came to Europe at the end of the 15th century and because it could be eaten fresh, it slowly displaced the sour orange.

Citrus aurantium 'Chinotto' © Tradewinds

Uses

Sour oranges are not eaten fresh. Their importance lies in the oil that can be extracted from the flowers, leaves, seeds and rind. This oil gives its typical orange-like flavour to spices, sweets, liqueurs etc. Some types of the Citrus aurantium family impart their aroma to expensive perfumes, soaps and after-shaves. The oils from sour oranges are used in aromatherapy and many health products.

The dried flowers and buds as well as some oils are used in blendings of fine tea. The whole fruit is used to make the orange marmalade the British prefer. Certain sour oranges are caramelized whole and eaten as a dessert. The main constituent in the aroma of many soft drinks is sour orange. More detailed information on uses can be found in the description of each variety.

Taste

Quite often the taste of orange in food products comes from the sour orange. Marmalade made of sweet oranges only does not have a strong taste of orange, surprisingly enough. The same is true of sweets, chocolates and liqueurs. But when a few drops of the essence of sour orange is added a strong taste of orange emerges. The alcohol products marketed as orange liqueurs are all made of sour orange. Several varieties are planted for ornamental purposes because of their thick and beautiful foliage as well as their plentiful fruit, which remain on the trees for most of the year. Visiting Spain and other Mediterranean countries one may have thought it peculiar that so many beautiful orange trees in full fruit line the promenades and boulevards. Picking a fruit to taste it one may have been disappointed to find it inedible. Most likely it was one of the several varieties of sour orange.

Varieties

More than fifty cultivated varieties of sour orange are known. About twenty are of commercial importance. Sour oranges are divided into four main groups. The varieties described below are mentioned after each group:

1. Common sour oranges: Sevillano

2. Bittersweet oranges: Bittersweet and Leather-head
3. Ornamental varieties: Bouquetiers (Perfumery varieties) and Myrtle-leaved orange
4. Variant sour oranges: Daidai, Tosu and Bergamot

Names

Chinotto, Citrus aurantium var. myrtifolia

This page describes the sour orange, Citrus aurantium, which is a species of its own. In culinary uses and recipes it is often called Seville orange. The name bitter orange is also used. The sweet orange or Valencia orange (Citrus sinensis) has a page of its own.

Recent study using the latest technology has confirmed that these two kinds of citrus are two separate species in spite of their deceivingly similar appearance. One is not a mutation or variety of the other. They most likely arouse one after the other from the same parentage (as hybrids of pomelo and mandarin, cf. The genus Citrus) but each containing a different genetic structure manifesting different traits. It is also possible that both parents had already mutated a little with slightly different characteristics resulting in a new kind of hybrid.


LAT	Citrus aurantium L.
Syn	Citrus aurantium var. amara Engl.
	Sour orange, also known as bitter orange and in food contexts as Seville orange (top picture), very much resembles the sweet orange. The rind is usually much thicker, rough on the surface and hard to peel. The sour orange is seldom very juicy and it often has many seeds. When fully ripe the core at the centre of the segments becomes hollow. An important part of the world production is sold to England, Scotland and South Africa where it is made into marmalade. The orange marmalade preferred by the British is made out of sour oranges only and a marmalade made from sweet oranges is not acceptable. Some sour oranges are often added to regular sweet orange marmalade to improve its flavour. The dried peel of sour orange is used as a spice in baking and confectioneries. The flower of the sour orange (photos 2 and 3) is the source of Neroli oil (produced by steam distillation) and Neroli absolute (produced by solvent extraction). The flowers yield nectar for honey bees. Neroli petitgrain oil is made from leaves and twigs (photo 3 and photo 4) by steam distillation. Neroli bigarade oil is made from the peel of nearly ripe fruit by cold expression. These oils are widely used in perfumery and cosmetics, and as a flavouring agent in foods, alcoholic and soft drinks. They are also used in aromatherapy. For more information see citrus oils, bittersweet orange and perfumery varieties. Genuine orange flower-water is a by-product of the steam distillation of oils. The thick peel of certain types of sour orange, especially 'Jacmel' in Jamaica, is cut into segments, which are dried in the sun. They are then soaked in pure alcohol in a process called maceration. Later this mixture is distilled and the clear liquid obtained is used for flavouring citrus liqueurs such as Grand Marnier and Cointreau. The dried peel of a sour orange variety Citrus aurantium var. curassaviensis from the island of Curaçao is used in the making of citrus liqueurs Curaçao and Triple sec. The peel and seeds (bottom picture) also have medicinal uses and are used in making soap. All parts of the sour orange can be used. It adapts easily to varying conditions and survives with very little or no care. It can stand several degrees of frost for short periods. In proper conditions the tree can have exceptional longevity. Some trees in Spain are said to be over 600 years old and there is a tree growing in a container at Versailles, which was planted in 1421. The most common cultivated varieties are: Sevillano (see below), African, Brazilian, Rubidoux, Standard, Oklawaha and Trabut.
ENG	Sour orange, Common sour orange, Seville orange, Bitter orange
FRA	Orange amère (fruit), Oranger à fruits amers (tree)
GER	Bittere Orange, Pomeranze
I TA	Arancia amara, Melangolo
SPA	Naranja ácida, naranja agria (fruit), naranjo amargo (tree)
Photos		(1,2) with permission of Thomas Schoepke (3,4) © C. Jacquemond / INRA © UCR Citrus Variety Collection


LAT	Citrus aurantium 'Sevillano'
Syn	Citrus aurantium 'Real' Citrus aurantium 'Agrio de España' Citrus aurantium 'Sans épine'
	'Sevillano' is the sour orange variety grown in southern Spain in and around the city of Seville. The variety is also known by its Spanish name Real, the royal sour orange. This is the best known marmalade variety. It is exported chiefly to England and Scotland for orange marmalade production. The typical bitterness combined with its sour orange characteristics make it an ideal variety for this. The production area is around 5000 acres and the annual production around 20,000 metric tons (20 million kilos). This variety was brought to Spain by Arab conquerors in the 12th century from northern Africa via Morocco.
ENG	Seville orange, Common sour orange, Common bitter orange
FRA	Bigarade sans épine, Bigarade d'Espagne
Photos		(1) © C. Jacquemond / INRA © UCR Citrus Variety Collection


LAT	Citrus aurantium var. bigaradia Hook f. *	Dummet 'Bittersweet of Florida' Paraguay Bittersweet Citrus aurantium var. bigaradia 'Apepu'
Syn	Citrus aurantium ssp. aurantium Citrus bigaradia Risso & Poit. Citrus bigarradia Loisel. Citrus vulgaris Risso
	The bittersweet orange came from the Near East to Europe with the crusaders in the 12th and 13th centuries. The tree is known to have been commercially grown in the Nice area from the year 1322. This is the sour orange that first reached Paris and Versailles and became the favourite of kings and aristocracy or anyone who could afford to build the special greenhouses called orangerie that were needed for growing them. The Apepu, as it became known, was also the first orange to reach the New World with the second voyage of Columbus. It quickly established itself in suitable surroundings like Florida and Paraguay, where the largest cultivated areas still are and where it soon also escaped and started to grow wild. The tree is large and thorny, the fruit medium size, globose and with a smoother rind texture than the common sour orange. The rind is medium thick and seeds are numerous. The taste is sweet but bitter at the same time, a combination or orange and lime perhaps. In its cultivation area the bittersweet orange is used for making marmalade. In the Caribbean islands dried peel is used for giving aroma to citrus liqueurs. The juice is also used for marinades. The mojo of Cuba is a marinade half sour orange juice and half oil, spiced with garlic and onions. The leaves and twigs of the bittersweet orange are used to make petitgrain (Paraguay) oil by steam distillation. The peel of the immature fruit is used to obtain bigarade oil by cold expression. These oils are not as highly esteemed as Neroli petitgrain or Neroli bigarade from the common sour orange, but they are largely used in perfumery and in aromatherapy. For more information see citrus oils. Cultivated varieties: 'Bittersweet of Florida' and 'Paraguay' ('Apepu')
ENG	Bittersweet orange, Paraguayan Bigarade
FRA	Bigarade Paraguay, Bigarade Apepu
	*Several taxonomists have omitted the Citrus aurantium var. bigaradia variety and included it directly in Citrus aurantium proper. Because the bittersweet oranges are still considered a separate group and because their taste and uses differ from those of other sour oranges, the author of these pages has decided to retain this distinction. Properly, however, these cultivars should be considered cultivated varieties of Citrus aurantium.
Photos		© UCR Citrus Variety Collection (3) © C. Jacquemond / INRA


LAT	Citrus aurantium var. gou tou
Syn	Citrus aurantium var. gao tao Citrus aurantium var. goutoucheng Citrus aurantium var. pi-tou-chêng
	The Leather-head sour orange is one of the most common varieties in China and south-east Asia. A member of the bittersweet oranges, the Leather-head is used as root stock for other citrus varieties, especially sweet orange and mandarins, because of its better resistance to several diseases. The fruit are smallish, oblate, slightly depressed at both ends with many seeds and medium thick rind. The colour is yellowish and resembles that of grapefruit. The taste is acid with lime overtones.
ENG	Leather-head sour orange, Goutoucheng sour orange, Pi-tou-chêng sour orange
FRA	Bigarade Gou Tou
Photo		(1) © C. Jacquemond / INRA © UCR Citrus Variety Collection


LAT	Citrus aurantium ’Bouquetier’	'Bouquet de fleurs' 'Bouquet de fleurs' 'Bouquetier de Nice à fleurs doubles'
	Cultivated varieties: Citrus aurantium ’Bouquet de Fleurs’ Citrus aurantium 'Bouquetier de Nice' Citrus aurantium ‘Bouquetier à Grandes Fleurs’ Citrus aurantium ‘Bouquetier de Nice à Fleurs Doubles’
	There is some confusion about these perfumery varieties. On the French Riviera and around the town of Grasse as well as in Algeria and Tunisia several sour orange varieties are grown solely for their flowers, which yield a superior quality of Neroli oil that is used in perfumery and aromatherapy. The trees are small, some even dwarfish, and the small fruit are often discarded, although they can be used for making petitgrain and bigarade oils. The flowers of these varieties differ from each other. The flowers of the most highly prized varieties are doubled. The lower picture is of one of the most valued varieties called the Double-flowered Bouquetier of Nice. The oil obtained from these varieties is more expensive than gold. The word bouquetier means either a small narrow vase for holding nosegays or a flower-seller, the feminine form bouquetière means a flower-girl. Bouquet is a bunch of flowers, among other things. There are several named cultivars, see above. For more information on the oils, see citrus oils.
ENG	Bitter orange perfumery varieties
FRA	Bigarade bouquet de fleurs (bouquet) (Bigarade riche dépouille) Bigarade bouquetier de Nice Bigarade bouquetier à grandes fleurs (à peau épaisse) Bigarade bouquetier de Nice à fleurs doubles (bouquetier à fruits plats)
Photos		© UCR Citrus Variety Collection (3) © Home Citrus Growers


LAT	Citrus aurantium var. myrtifolia Ker-Gawl.	'Chinois à grandes feuilles'
Syn	Citrus myrtifolia Raf. Citrus bigaradia Risso & Poit. var. chinensis
	Myrtle-leaved orange gets its name from the myrtle (Myrtus communis) because its leaves resemble those of the myrtle. The leaves grow densely and the fruit hang on the tree for most of the year, which makes it an attractive ornamental plant. The myrtle-leaved orange is grown on the Mediterranean coast of France and in Italy as well as in the citrus zones of the US. The French call it chinois (Chinese). The tree was introduced from China. The Americans call it by its Italian name chinotto. There is an Italian home page for "chinottofiles", friends of the chinotto. The Chinotto homepage tells you everything you want to know about this tree, and more. Surprisingly it lists dozens of different kinds of soft drinks and beverages made of chinotto. Presumably most of these are only available in Italy, the promised land of chinotto enthusiasts. The fruit are too sour to be eaten fresh but they are candied whole and eaten as a luxury dessert. Four main varieties of chinotto are grown: cv. 'Chinotto buxifolia' ('Chinois à feuilles de buis') Boxwood-leaved chinotto cv. 'Chinotto crispifolia' Crinkle-leaved chinotto cv. 'Chinotto grande' ('Chinois à grandes feuilles') Large chinotto cv. 'Chinotto piccolo' ('Chinois à petites feuilles') Dwarf chinotto
ENG	Myrtle-leaved orange, Ornamental orange Chinotto orange, Myrtle leaf orange (US)
FRA	Orange à feuilles de myrte, Bigaradier chinois
GER	Myrtenblättrige Bitterorange
I TA	Chinotto, Arancio a foglia mirtella
SPA	Naranja mirtifolia
Photos		(1) © C. Jacquemond / INRA (2) © Petr Broža © UCR Citrus Variety Collection


LAT	Citrus aurantium var. daidai L.	Citrus natsudaidai Citrus nanshô-daidai Citrus natsumikan
	Citrus natsudaidai Hayata Citrus nanshô-daidai Citrus dadai-mikan Citrus natsumikan Citrus taiwanica Tanaka
	The Daidai sour oranges are a group of relatives of the sour orange grown mostly in Japan, China and Taiwan. Some authors list these directly under Citrus aurantium. However, especially in Japan the natsudaidai, dadai-mikan and natsumikan are classified as separate species. Members of the daidai group have large fruit with a thick skin that is hard to peel. The fruit usually have sour juice and many large seeds. Fermented sour orange vinegar is made from the juice. The dried flower buds and flowers are used in fine grades of scented tea. The daidai varieties are used as ornamental plants because they produce fragrant flowers throughout the year and the fruit can hang on the trees for over a year. Sometimes the fruit only fall when pushed out of the way by developing new fruit. Unlike other sour oranges, in fact unlike most citrus trees, the fruit of the daidai mature in summer.
ENG	Daidai sour orange Japanese summer orange Japanese bitter mandarin
FRA	Bigarade natsudaïdaï, Bigarade nanshô-daïdaï
Photo		© UCR Citrus Variety Collection (3) © Petr Broža


LAT	Citrus aurantium ’Tosu’
Syn	Citrus neoaurantium Tanaka Citrus bigaradia var. tosu
	The tosu is a variety of sour orange that originates in Okitsu on the Honshu island of Japan. The fruit are somewhat depressed at both ends.
ENG	Japanese Tosu orange
FRA	Bigarade Tosu
Photo		(1) © C. Jacquemond / INRA © UCR Citrus Variety Collection


LAT	Citrus aurantium ssp. bergamia (Risso et Poit.) Wight & Arn. ex Engl.
Syn	Citrus bergamia Risso Citrus aurantium var. bergamia Loisel.
	The Bergamot is mostly grown in Italy. Bergamot oil is extracted by cold expression from the peel of half-ripe fruit (picture 2). It is used in aromatherapy and as a scent in Earl Grey tea. Bergamot oil is also used to flavour confectionery, sweets, marmalades and citrus liqueurs. Bergamot petitgrain oil is extracted from the leaves and twigs by steam distillation. It is used to scent after-shaves and toilet waters. The main scent in the original ’Eau de Cologne 4711’ is bergamot. A more inexpensive oil is derived by steam distillation of the crushed fruit. This oil is used in cosmetics, soaps and washing powders. See citrus oils. Cultivated varieties: 'Castagnaro', 'Fantastico' and 'Femmenillo'
ENG	Bergamot, Bergamot orange, Lemon bergamot
FRA	Bergamote, Bergamotier (tree)
GER	Bergamotte, Strauchorange
I TA	Bergamotta (fruit), Bergamotto (tree)
SPA	Bergamot
Photos		(1) © C. Jacquemond / INRA (2) © Franck Curk / INRA © UCR Citrus Variety Collection