Protein biofortified sorghum : effect of processing into traditional African foods on their protein quality

Abstract

Protein biofortification into crops is a means to combat childhood protein-energy malnutrition (PEM) in developing countries, by increasing the bioavailability of protein in staple plant foods and ensuring sustainability of the crop. Protein biofortification of sorghum has been achieved by both chemically induced mutation and genetic engineering. For this biofortification to be effective, the improved protein quality in the grain must be retained when it is processed into staple African foods. Suppression of kafirin synthesis by genetic engineering appeared to be superior to improved protein digestibility by chemical mutagenesis, because both the lysine content and protein digestibility were substantially improved and maintained in a range of African foods. For the genetically engineered sorghums, the protein digestibility corrected amino acid score was almost twice that of their null controls and considerably higher than the high protein digestibility sorghum type. Such protein biofortified sorghum has considerable potential to alleviate PEM.