Essential corrections of interference reactions in the determination of protein contents of Nigeria foodstuffs using fast neutron activation analysis

Using the 14N(n, zn)13N reaction, the protein contents of some Nigeria staple foods were estimated. The contribution of some elements in these foods such as Br, P, K and the recoil proton to the 511 KeV photopeak commonly used in this technique was investigated. While Br was found absent from the high carbohydrate foods such as the cassava tuber based “gari’, maize and rice, this element was shown to produce significant interference in broad beans and soya beans. The contribution of Br to the 511 Kev line in protein measurement in the latter set of food materials ranged between 12% and 62%. Proton recoil were found to be a significant source of interference in virtually all the food stuffs investigated. The result of protein contents using 14 MeV compared favourably, within experimental errors, with that of the wet kjeldahl method, except in the case of soya beans which indicates an underestimation of the contribution from the recoil proton.