The effects of moisture, propionic acid, sodium hydroxide and anaerobiasis on the stability of vitamin E in stored barley

SUMMARY Two experiments were designed to measure the effect of current barley storage systems on vitamin E stability. Whereas propionic acid and sodium hydroxide treatment of moist barley results in destruction of vitamin E, neither moisture per se nor anaerobic storage has such a detrimental effect. The destruction is most severe and rapid with alkali treatment, the reaction having substantially reached completion by 5 days. All the vitamin E isomers were affected to varying degrees, the order of susceptibility to decay being α-tocopherol > γ-tocopherol > α-tocotrienol > γ-tocotrienol. Possible explanations are given as to why the findings incriminating propionic acid in vitamin E destruction are at variance with currently held opinion.