A Methodological Review of Strategies for Artificial Contamination of Solid Food With Aspergillus flavus and Aflatoxin B1: Insights Into Growth Dynamics, AFB1 Production, and Spiking Techniques for Cereals, Nuts, and Seeds

Abstract

Aspergillus flavus (A. flavus), is a prevalent contaminant of solid food and feed. It produces aflatoxin B₁ (AFB₁) and B₂ (AFB₂) posing significant toxicological risks to both humans and animals. Extensive research has been conducted to develop reliable methods for AFB1 detection, A. flavus control, and AFB1 reduction. However, these methods require consistent sampling of contaminated cereals, nuts, or seeds. Yet, naturally contaminated samples often pose challenges due to nonhomogeneous mold distribution, co-infection by other fungal genera, and multi-mycotoxin contamination. Therefore, researchers often rely on artificially contaminated samples to ensure accurate and reproducible results. Artificial contamination can be achieved either by inoculating A. flavus spores allowing in situ AFB₁ production under optimal conditions or by spiking grains or kernels with AFB₁. The objective of this review is to report protocols for artificially contaminating solid food, beginning with an overview of the morphology and life cycle of A. flavus. It critically analyzes methods used for contaminating cereals, nuts, and seeds, with attention to pretreatment procedures, experimental steps, and optimal growth conditions for A. flavus and AFB₁ production. It is intended as a comprehensive reference in the matter, providing essential information for preparing representative samples of artificially contaminated food with A. flavus or AFB₁.