The fate of B-aflatoxins was studied during the toasting and boiling of contaminated maize. One lot of aflatoxin-free grain served as the control Lot 1 (L1). Lot 2 (L2) and Lot 3 (L3) had aflatoxin concentrations of 120.7 and 575.0 mug kg(-1). In the case of contaminated pinole-powder, the aflatoxin content was 22.9 for L2 and 171.0 mug kg(-1) for L3 and, after atole preparation (a Mexican porridge-like drink), the aflatoxin content was 9.7 and 68.2 mug kg(-1) for L2 and L3, respectively. According to these results, higher reductions in mycotoxin levels were achieved during the toasting process and only a moderate extra-reduction occurred during the boiling process. (C) 2004 Elsevier Ltd. All rights reserved.