Carob (Ceratonia siliqua)
FABACEAE, Legume Family
Many residents of southern California have seen carob trees (Ceratonia siliqua) planted around town. Carob is an evergreen tree with pinnately compound leaves (have 2 to 6 pairs of oval leaflets), which can grow to a height of 15 meters and be very handsome. Nevertheless, this species is grown around the world primarily as a food crop, for its sweet and nutritious fruits.
Carob is native to the eastern Mediterranean, probably the Middle East, where it has been in cultivation for at least 4000 years. The plant was well known to the ancient Greeks, who planted seeds of this plant in Greece and Italy. There are references to carob in the Bible. For example, this plant is also called St. John's bread or locust bean because the pods were once thought to have been the "locusts" that were eaten by John the Baptist in the Wilderness. That story was apparently wrong--he ate migratory locust. Seeds were used to weight gold, hence the word "carat." Mohammed's army ate kharoub, and Arabs planted the crop in northern Africa and Spain (Moors), along with citrus (Citrus) and olives (Olea). Spaniards carried carob to Mexico and South America, and the British took carob to South Africa, India, and Australia. Records show that carob was intentionally introduced into the United States in 1854, and the first seedlings were apparently planted in California in 1873. For commercial production cultivars with the finest quality fruits are bud grafted on common stock. Carob grows well anywhere that citrus is grown, and it prefers dry climates that receive more than 30 centimeters of rainfall--ideal mediterranean-type climates.
The fruit of carob is a pod, technically a legume 15 to 30 centimeters in length and fairly thick and broad. Pods are borne on the old stems of the plant on short flower stalks. Interestingly, most carob trees are monoecious, with individual male and female flowers. The dark-brown pods are not only edible, but also rich in sucrose (almost 40% plus other sugars) and protein (up to 8%). Moreover, the pod has vitamin A, B vitamins, and several important minerals. They can be eaten directly by livestock, but we know carob mostly because the pods are ground into a flour that is a cocoa substitute. Although this product has a slightly different taste than chocolate, it has only one-third the calories (total 1595 calories per pound), is virtually fat-free (chocolate is half fat), is rich in pectin, is nonallergenic, has abundant protein, and has no oxalic acid, which interferes with absorption of calcium. Consequently, carob flour is widely used in health foods for chocolate-like flavoring. A very fine polysaccharide gum--mucilaginous, odorless, tasteless, and colorless--can also be obtained from the pod and is now used in many products. There are also several putative medicinal uses of the plant, and singers formerly chewed the pod husks in the belief that this clears the throat and voice.
Most carob used in this country comes from the Mediterranean Region, especially Sicily, Cyprus, Malta, Spain, southern Sardinia, and Italy along the Adriatic Sea. Carob can be produced in California, and was grown for a while in the Southland, but this has not been economically successful because the land is too valuable to devote to this crop.
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