An acoustic apparatus and method for using a combination of low-frequency and high-frequency vibration of dried food, grain being an example, such that there are a large number of collisions among the individual grain particles for destroying microorganisms that reside on the surface or just below the surface of the grain, are described. Embodiments of the invention permit bulk and continuous processing of the food. It is expected that such collisions do not produce any chemical changes in the food, nor should it have any adverse effects on the taste thereof. Embodiments of the apparatus are applicable to destruction of airborne microorganisms.

Methods and apparatus for separating and removing aflatoxin-contaminated corn from batches of corn by a floating process, thus producing a distinguishable floating mat of contaminated corn and a separate submerged bed of uncontaminated and less contaminated corn. The methods of this disclosure include removing the floating contaminated corn mat by a vacuum mechanism or by liquid flow. The methods reduce the aflatoxin level in the submerged corn bed as much as 80% from the initial aflatoxin level, while removing no more than 15% from the batch of corn.

Methods and apparatus for separating and removing aflatoxin-contaminated corn from batches of corn by a floating process, thus producing a distinguishable floating mat of contaminated corn and a separate submerged bed of uncontaminated and less contaminated corn. The methods of this disclosure include removing the floating contaminated corn mat by a vacuum mechanism or by liquid flow. The methods reduce the aflatoxin level in the submerged corn bed as much as 80% from the initial aflatoxin level, while removing no more than 15% from the batch of corn.