ANTI-NUTRIENTS OR ANTI-OXIDANTS IN CEREAL GRAINS: AN EVALUATION OF THE COMPOSITION AND FUNCTIONALITY OF PHENOLIC COMPOUNDS WITH SPECIAL REFERENCE TO SORGHUM AND BARLEY T Beta

Phenolic compounds (phenolics) in cereal grains encompass a diverse group of secondary plant metabolites. They can be conveniently divided into three broad groups, phenolic acids, flavanols, and polymeric flavanols including condensed tannins. Agronomically, the presence of phenolics is associated with diminished pre-harvest losses due to bird predation and post-harvest losses due to storage pests. However, tannins bind proteins, carbohydrates and minerals, thereby affecting the nutritional and functional value of the bound constituents. Phenolics may also impart undesirable colours in grain products during food processing. Recent investigations using sorghum grains have focused on examining the types and levels of phenolic compounds as constituents that adversely affect nutritional and sensory quality of food. The protocol included identification of widely cultivated sorghums, determination of phenolic compounds, and investigations on effective methods of processing tannin-rich sorghums. The primary objective is to improve the acceptance and utilization of sorghum for food as well as overall food security. The use of chemical treatments to reduce phenolics, reduce the enzyme inhibitory power of sorghum tannins and improve dry- and wet- milling properties of sorghum is discussed. Data is presented on phenolic compounds in barley. The functionality of cereal phenolics as anti-oxidants is also discussed