Prolamins are a group of plant storage proteins having a high proline content. They are found in plants, mainly in the seeds of cereal grains such as wheat (gliadin), barley (hordein), rye (secalin), corn (zein), sorghum (kafirin), and oats (avenin). They are characterised by a high glutamine and proline content, and are generally soluble only in strong alcohol [70-80%] solutions, light acids, and alkaline solution. They do not coagulate in heat. They hydrolyse into prolin and ammonia. Some prolamins, notably gliadin, and similar proteins found in the tribe Triticeae (see Triticeae glutens) may induce coeliac disease in genetically predisposed individuals.