Postharvest handling practices and occurrence of aflatoxins in Shea kernels randomly picked from households in Bungatira Subcounty Gulu district northern Uganda

Abstract

Aflatoxin contamination of food stuffs have become of serious concern across the globe especially in developing countries such as those in Africa and Asia (especially in the eastern region of Asia) due to their carcinogenic, immunosuppressive, growth retardation effects in both man and animals. This study evaluated post-harvest handling practices and Aflatoxin contamination of shea kernels in Bungatira Sub-County Gulu District. A questionnaire as well as critical observation was used to ascertain the post-harvest handling practices. Most (80%) of the farmers handled the shea kernels poorly by spreading them on the bare ground during drying. During storage, handling of the shea kernels was relatively proper with most (63.3%) stored in sacks. De-husking of shea kernels was widely (80%) practiced and also most (70%) of the farmers practiced accumulation, which prolonged storage periods and may have increased the vulnerability of shea kernels to Aflatoxin contamination. Moisture content of the shea kernel samples was determined to ascertain the level of drying; the mean moisture content was 7.4%, well below 12.5% safety limit which indicated that drying was adequate. Detection of Aflatoxin in the shea kernel samples was done by Thin Layer Chromatography. Most (90%) of the samples were positive for aflatoxins. Most (80%) of the samples tested positive for Aflatoxin type B, 40% were positive for Aflatoxin type G, similarly for both B and G types. Association between the handling practices and Aflatoxin contamination was determined by Pearson’s Chi Square Test at 95% Confidence Interval (P