Ceratonia siliqua, commonly known as the carob tree (from Arabic خَرُّوبٌ kharrūb and Hebrew חרוב haruv), St John's-bread, or locust bean (not to be confused with the African locust bean), or simply locust-tree, is a species of flowering evergreen shrub or tree in the pea family, Fabaceae. It is widely cultivated for its edible pods, and as an ornamental tree in gardens. The ripe, dried pod is often ground to carob powder, which is used to replace cocoa powder. Carob bars, an alternative to chocolate bars, are often available in health-food stores.
Carob consumed by humans is the dried (and sometimes roasted) pod. The pod consists of two main parts: the pulp accounts for 90% and the seeds for 10% of the pod weight.
While chocolate contains levels of theobromine which are toxic to some mammals, carob contains absolutely no caffeine and no theobromine, so is used to make chocolate-flavored treats for dogs.