Evaluation of corn drying and storage techniques to mitigate damage and total aflatoxin contamination in Mozambique

Contamination of corn by molds and aflatoxins is a major problem in Mozambique, and appropriate drying and storage of this essential food crop is crucial. This study aimed to evaluate the effects of different drying and storage techniques traditionally employed by smallholder farmers in the province of Gaza, Mozambique, in preventing degradation and aflatoxin contamination of corn. Two trials, one for drying and one for storage, were carried out in 2024 and 2025, based on the information resulting from interviews applied to 90 farmers. For corncob drying, three methods were tested: ground, straw mat and tarpaulin. For grain storage, hermetic (metallic drums and PICS bags) and non-hermetic (raffia bags and traditional barns) methods were tested for 12 months of storage. Grain moisture, damage and total aflatoxins were evaluated. All drying methods resulted in a sharp corn moisture reduction, but tarpaulin drying showed the lowest grain damage. No significant differences were observed in aflatoxin content between drying methods. For storage, corn grains (initial 12 % moisture content) stored in metallic drums and hermetic bags were intact after 12 months, while storage in traditional barns and raffia bags resulted in highly (60–80 %) and completely (100 %) damaged grain after 3 and 6 months, respectively. Corn stored in raffia bags showed the highest aflatoxin contamination levels. This study confirmed tarpaulin and hermetic technologies as the most effective methods of corn drying and storage. However, information, demonstration and training are still required for farmers to implement these technologies, which are more expensive than the less effective ones. • Traditional Mozambican corn drying practices were tested. • Tarpaulin was the drying method resulting in fastest drying of corn combs. • Hermetic and non-hermetic storage devices were tested for corn long-term storage. • Hermetic bags and metal drums resulted in the lowest grain damage for 12 months. • Raffia bags and traditional barns led to total grain damage after 6 months of storage.