Oranges, limes, lemons, shaddocks, citrons, and grapefruits are all grouped under the category of citrus fruit. All such fruits are considered by botanists to be berries of a special type called hesperidium. Where citrus fruits growCitrus fruits grow only in warm subtropical and tropical regions. Earlier, few people in the cooler regions were able to get citrus fruits. However, the development of fast transportation and cold storage made it possible to preserve and carry the fruits over great distances. Physical characteristicsCitrus fruits have leathery peels, or rinds, and fleshy, edible interiors. The flesh, or pulp, is divided into eight or more sections that contain many seeds and tiny juicy pouches. Many of the more popular varieties of citrus fruits are grown to be seedless. How citrus fruits are grownCitrus trees, such as orange trees, are grown in groves using a technique known as grafting. A twig or a bud is cut from the stem or branch of an orange tree. This portion called the scion is then placed on the stem of another orange seedling that is well rooted. The rooted plant is called the rootstock. Tape, rubber, and even nails can be used to tightly join the scion and the rootstock. The two halves later grow together neatly, and a new orange plant comes up. Citrus trees need rich soil. The ground is fertilized with nutrients to encourage the growth of the plant. The trees begin to bear fruit anytime from three to six years after planting. Citrus trees may live as long as 150 years. Insect pests and fungus diseases can attack the groves. Scale insects are pests that attack the orange tree. Certain insects, such as the Australian ladybird, eat the scale insects. This means of natural control helps reduce need to use chemical sprays. Excessive spraying of chemicals can be harmful. Types of fruitsOrangesOranges grow on trees that reach 15 to 30 feet (4.6 to 9.1 meters) in height. The trees have fragrant, waxy, white blossoms. The leaves are glossy and evergreen, and the branches have small thorns. In the United States oranges are grown in the states of Florida and California and, to a lesser extent, Texas and Arizona. The typical Florida orange is thin-skinned. Its natural color is yellowish or yellowish-orange. Florida also grows Valencia and mandarin oranges. Although most Florida oranges are processed into juice, Valencia and mandarin oranges are mainly sold as fresh fruit. The seedless navel orange became a major fruit in California after it was introduced from Brazil in 1873. California has a long fruit-bearing season. Navel oranges are picked from November to May. GrapefruitGrapefruit is so named because it grows in grapelike clusters of three or more. The trees can grow to a height of about 50 feet (15 meters). They are grown to a height of 15 to 25 feet (4.6 to 7.6 meters) in groves. The leaves are dark and shiny green with large, white, sweet-smelling flowers. The young trees begin to bear fruit in five or six years. Trees begin blossoming from February to May, and the fruit ripens in about eight months. The fruit is grouped into two categories, white-fleshed and pink-fleshed. The grapefruit was introduced into Florida in about 1823, but nobody tasted it until about the 1880s. Today, growing and marketing grapefruit is a major industry in southern Florida, Arizona, and the Rio Grande valley of Texas. The United States, Israel, Cuba, Argentina, Cyprus, South Africa, and Mexico are large producers of grapefruit. ShaddockShaddock is probably named after the sea captain who introduced the tree to the West Indies. It is also called pummelo and is probably native to Malaysia and Polynesia. The tree grows to a height of 20 to 40 feet (6 to 12 meters). The leaves of the shaddock resemble those of the orange. The flowers are large and white. The fruit is big and almost pear-shaped. It is lemon yellow in color and has a tart but pleasant flavor. The pulp segments are either pale white or red and shell out easily. The fruit is very popular in Asia. LimesThe lime is a small round fruit with greenish-colored pulp. It has a thin rind, or peel, and sour, acidic juice. The lime tree is a native of southeastern Asia and South Asia, particularly India. It is very sensitive to cold weather. Most of the limes sold in the United States come from plantations in the West Indies, Mexico, and Florida. There are two major types of limes, the Mexican lime and the Tahiti lime. The Mexican lime is also called West Indian or Key lime and has a small seedy fruit. The Tahiti lime, sometimes called the Persian lime, has a larger seedless fruit. Lime trees do not grow as tall as other citrus trees, and they start bearing fruit in the third year. They are fully grown when they are six or seven years old. LemonsLemon trees cannot bear cold as well as orange trees. Hence, the area of its growth is more restricted. Lemons have long been grown in Spain, Portugal, Italy, Sicily, and Corsica. In the United States California is an important lemon producer. Lemons are grown in much the same manner and regions as oranges. The lemon tree has straggling branches, unlike the dense foliage of the orange tree. Lemon flowers are purplish. The lemon tree flowers continuously and has fruit at all stages of development most of the year. A tree may bear as many as 3,000 lemons annually. Most lemons ripen naturally in autumn and winter when the demand for lemons is low. Therefore, the growers pick the lemons green and store them for sale in the spring and summer. Lemons are picked when they reach a satisfactory size and juice content. UsesIn the late 19th century, James Lind, a Scottish naval surgeon, found that people with a disease called scurvy could be cured if they drank the juice of citrus fruits. Scurvy is a disease caused by a deficiency of vitamin C in the diet. Later, scientists discovered that citrus juice is beneficial because it is rich in vitamin C. The demand for citrus fruits increased greatly after this discovery. Citrus juice also contains vitamin A, vitamin B, and some minerals needed by the body. In 1944 scientists found a way to preserve orange juice in a vacuum and then freeze it without destroying the flavor and nutrients. The frozen juice became widely available and popular. Most of the orange crop in the United States goes to processing plants that pack canned juice, orange segments, and marmalade. After the oranges have been processed for these products, the rest is used as a feed for livestock, pectin for making jellies, citric acid, essential oils, molasses, and candied peel. Grapefruit is generally eaten raw. Sometimes it is peeled and the segments are canned for salads and appetizers. The juice is canned or frozen. Lime juice is often concentrated by evaporation and marketed as a flavoring. British sailors are called “limejuicers” or “limeys” because of the British law requiring a regular allowance of lime or lemon juice at sea to prevent scurvy. The lemon is used in more ways than any other citrus fruit. The pulp yields juice containing a substance called citric acid. The juice is used in flavoring foods and drinks. Lemon juice can also be used as a bleaching, or color lightening, agent in the printing of cotton fabrics. Lemon oil is obtained from the rind. This extract is used in flavoring and in making perfume and some medicines. The rind can be cooked with sugar to make candied lemon peel. HistoryCitrus fruits are native to southern China and South and Southeast Asia. They have been grown there for approximately 4,000 years. Arab traders in Asia carried lemons, citrons, limes, oranges, and shaddocks to eastern Africa and the Middle East between the 2nd and 8th centuries. During the Arab occupation of Spain, citrus fruits arrived in southern Europe. From Europe they were carried to the Americas by European explorers. Citrus fruits were well known in Florida and Brazil by the 16th century. Superior citrus varieties from Southeast Asia arrived in Europe with Portuguese traders in the 16th century. By the 1800s citrus fruits had been distributed worldwide by explorers and missionaries. |