Aspergillus is a fungus that essentially belongs to grains storage flora. It grows optimally at 25Â°C with a minimum necessary water activity of 0.75. It starts to produce secondary metabolites at 10-12Â°C, but the most toxic ones are produced at 25Â°C with a water activity of 0.95. Those toxic secondary metabolites named aflatoxins (AF) is a group of mycotoxins produced by a large number of Aspergillus species, basically by three phylogenetically distinct sections. The main producers are A. flavus, and A. parasiticus, but it has been demonstrated that A. nomius, A. pseudotamarii, A. parvisclerotigenus, and A. bombycis of section Flavi, A. ochraceoroseus and A. rambellii from section Ochraceorosei and Emericella astellata and E. venezuelensis from Nidulatans section also generate aflatoxins.