The effect of harvest, sorting and drying practices on aflatoxin contamination of maize

Abstract

Aflatoxins are the result of fungal metabolites that contaminate agricultural produce and can cause death to both humans and animals. The risks of using contaminated food and feed with aflatoxins have increased due to environmental factors, pre-harvest, post-harvest and socio-economic factors. This study revealed on harvesting, drying, and sorting practices that can reduce aflatoxin contamination. Experiments were designed in three districts; Kilosa, Gairo, and Mvomero with five (5) treatments replicated nine (9) times under farmers’ conditions. Samples were collected during harvesting, drying, and sorting; and analyzed for aflatoxin B1 using High Performance Liquid Chromatography (HPLC) at Tanzania Bureau of Standards (TBS) laboratory. Analysis of variance and comparison of means for moisture content, mold levels, grain damage, and aflatoxin levels were performed using GenStat® Executable release 16 Statistical Analysis Software. Results indicated that aflatoxin contamination levels were lower at maize grain harvested into bags (456.9μg/kg) compared to maize harvesting onto the ground (889.1μg/kg). It was also observed that maize dried on tarpaulin and raised platform had significantly (p<0.05) low aflatoxin levels (65.5 μg/kg, 67.1μg/kg respectively) while maize dried on the ground had higher aflatoxin infestation (179 μg/kg). Again, sorting maize by color significantly (p<0.05) reduces aflatoxin contamination. These results indicate that proper postharvest management of maize, such as harvesting maize on bags, drying maize on tarpaulin, raised platform and sorting maize by color gives the lowest aflatoxin contamination levels. Hence, proper education to farmers on harvesting maize using container/bags and drying maize on raised platform to be established in farmer level.