This article investigates the use of cereal barley (hordeum vulgare) in Islamic society between the 9th and 15th centuries. Among barley products, barley bread, boiled barley water, barley porridge, and parched barley are attested in dietetic works (both cuisine and medicine), agricultural manuals, works of literature, and so forth.
Works of adab literature and the sole extant agriculture manual from the period (10th c.) show that between the 9th and 12th centuries, barley bread was the staple food of the peasantry and that barley was deemed the cereal most suitable to the peasants' nutritional needs.
Among the many references to food in the hadith, both barley bread and barley porridge are mentioned as dishes enjoyed daily by the Prophet and his followers.
The dietetic sources treat barley as a medicament for cooling the body. On the other hand, in the sole extant book of cooking recipes from the period (10th c.), barley does not appear except as the main ingredient of barley water. While barley continued to be prescribed for medicinal purposes, the members of the Abbasid court and the urban elite apparently did not consider it an important ingredient of their food.
Sources from the 13th century on describe barely products being used in urban society under such conditions as hot weather, outbreaks of plague, or high fever. They show in particular that barley water was a daily household necessity for urban dwellers.
The spread of the consumption of barley water and other barley products in the urban society from the 13th century on reflects the incessant outbreaks of famine and plague that cities in the Islamic society were suffering at that time.