Evaluation of the Factors Affecting the Phosphine Residue in the Fumigation–Aeration Process of Stored Wheat Using Orthogonal Array Design

Abstract

Factors that affect the phosphine residue in the fumigation–aeration process were studied. Simulated experiments were carried out on the samples in nine different conditions (nine treatments using L9 orthogonal array on four factors: amount of aluminum phosphide, fumigation time, aeration time, and fumigation temperature). The extracted phosphine residue of grains was quantified by UV/visible spectrophotometry at 410 nm. The results revealed that the most important factors are the aeration and fumigation time. The fumigation temperature has negligible effect on the phosphine residue, and there is no significant effect from the amount of aluminum phosphide. Under optimum conditions, the phosphine residue content was 0.0067 mg/kg of wheat grain, which is very less than the reported amounts by related organizations.