Enhancing utilization of cowpeas through gamma irradiation modification of functional properties

Abstract

A major reason for the low utilization of cowpeas in southern African countries is the absence of variety in the foods prepared from cowpeas in these areas. In these countries, this legume is utilized primarily in the form of boiled whole seeds. Processing cowpea seeds to flour as well as to protein and starch functional ingredients may broaden the application of cowpeas. This may facilitate the production, promotion and use of cowpeas. To achieve tailored and specific uses in food systems, modification of functional properties of cowpeas may be required. Several techniques including the use of gamma irradiation are available to Food Scientists in this respect. Gamma irradiation has the potential to modify the functional properties of cowpeas mainly through its effects on inherent protein and starch components. The effects of γ-irradiation on the functional properties of cowpea flour, as well as on protein and starch isolated from irradiated cowpea flours, were studied. The results show that most protein-related functional properties were significantly modified at 10 and/or 50 kGy whereas starch-related functional properties were modified at doses as low as 2 kGy. Some of the implications of these functional modifications of cowpea flour and its main components in relation to food systems are highlighted in this paper.