Physical and biological approaches to prevent aflatoxin contamination in peanuts and the agricultural environment

The objective was to use physical (solar drying) and biological approaches (composting) to prevent aflatoxin contamination in peanuts and the agricultural environment. For solar drying, an indirect wooden solar dryer was constructed. The performance was determined by drying 18-72 kg of freshly harvested peanuts. Equal amounts of peanuts were dried simultaneously on cement concrete floor under open sun for comparison. Composting was conducted using aflatoxin-contaminated peanut meal as a model matrix at 40C for 6 wk. Water and three different commercial starters and/or an accelerator were added to the contaminated peanut. Aflatoxin B1, B2, G1 and G2 were quantified at the end of each week. Solar dried peanuts attained moisture content below 10% in four days. Peanuts in the solar dryer experienced much lower temperatures than those dried under the open sun. Solar dried peanuts had a lower level of lipid oxidation and a higher rate of germination compared to open sundried peanuts. Composting reduced aflatoxin levels in aflatoxin-contaminated peanut meal.