Cereal plant of the genus Hordeum, in the family Poaceae (or Gramineae), and its edible grain. The three cultivated species are H. vulgare, H. distichum, and H. irregulare. Barley is adaptable to a greater range of climate than any other cereal. About half of the world's crop is used as livestock feed, the rest for human food and for malting. Most beer is made from malted barley, which is also used in distilled beverages (see malt). Barley has a nutlike flavour and is high in carbohydrates, with moderate quantities of protein, calcium, and phosphorus. Barley flour is used to make unleavened bread and porridge. Pearl barley, the most popular form in many parts of the world, is often added to soups.
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