Physical Methods for Reduction of Aflatoxins Exposure in Groundnuts in Some Low-Income Countries: A Review

Aflatoxin (AF) is a powerful carcinogen primarily produced by some strains of the fungus Aspergillus flavus and Aspergillus parasiticus, which frequently infest nuts and cereal crops. Groundnuts are among the most widely studied substrates of Aspergillus spp., growth and AF contamination. Aflatoxin contamination is a significant public health concern since chronic exposure is linked to causing carcinogenicity, teratogenicity, hepatotoxicity, estrogenicity, neurotoxicity, childhood growth impairment, and immunotoxicity in humans and animals. Acute exposure to AF contamination is associated with fatal aflatoxicosis due to nausea, vomiting, abdominal pain, and convulsions. Good agricultural practices, control of plant diseases, and favourable storage conditions can limit AF contamination yet do not guarantee complete elimination. Looking for an effective technique to reduce AF to an acceptable regulatory limit has been a great subject among researchers. Physical methods like manual visual sorting, screening, density, roasting, dehulling, winnowing, and decortication can reduce AF contamination while maintaining the quality of the kernel and render the kernels harmless to humans and animals compared to AF degradation by chemicals. Therefore, the present review article found that physical removal/visual sorting efficiently lowered the mean AF content commonly used in low-income countries. We briefly enumerated the effectiveness of various common physical methods in reducing post-harvest AF contamination in groundnuts, particularly their percentage AF reduction and outsort/loss, sufficient AF reduction evidence, feasibility, and scalability. We also highlighted the merits and demerits of these methods and essential information that could be helpful for further investigation.