title: Effect of microwave heating during alkaline-cooking of aflatoxin contaminated maize.
abstract: To evaluate the effectiveness of maize detoxification achieved with a modified tortilla-making process (MTMP), maize contaminated with aflatoxin B(1) (AFB(1)) and aflatoxin B(2) (AFB(2)) at levels of 22.46, 69.62, and 141.48 ng/g (AFB(1)+ AFB(2)) was processed into tortillas. Aflatoxin content was determined according to the 991.31 AOAC official method. Based on the results obtained with spiked samples (0.78 to 25 ng/g), the mean recovery was 92%, with a standard error of 1.2, and a coefficient variation value of 4.4%. The MTMP caused 68, 80, and an 84% decrease in aflatoxin content, respectively. Extract acidification (as occurs during digestion) prior to mycotoxin quantification caused some reformation of the aflatoxin structure in tortillas (up to 3%). According to these results, the MTMP seems to be safe for decontamination since a low percentage of the initial aflatoxin concentration can be reverted to the original fluorescent form upon acidification.
  
  
  CONCLUSIONS
  The potential presence of aflatoxins in maize destined for human consumption is a serious problem to the Mexican food supply, as these toxic compounds may persist during the traditional alkaline-process for tortilla elaboration. Consequently, new detoxification procedures are needed that eliminate or at least minimize the aflatoxin risk, through lowering aflatoxin concentration in maize-based products. Under these considerations, the use of MTMP is recommended, since it has definite advantages including non-production of wastewater and reduced energy/time consumption.
authors.affiliation: UNAM-FESC, Campus 4, UNIGRAS, Unidad de Investigación Multidisciplinaria, Cuautitlán Izcalli CP 54714, México.
authors.forename: G C
authors.initials: GC
authors.lastname: Pérez-Flores
authors.forename: E
authors.initials: E
authors.lastname: Moreno-Martínez
authors.forename: A
authors.initials: A
authors.lastname: Méndez-Albores
mesh_terms: D016604:Aflatoxin B1 / Q000032:analysis*; D001231:Aspergillus flavus / Q000302:isolation & purification; D003296:Cooking; D003666:Decontamination; D005506:Food Contamination; D005511:Food Handling / Q000379:methods; D006361:Heating; D008872:Microwaves; D003313:Zea mays / Q000737:chemistry / Q000382:microbiology*
chemical_list: D016604:Aflatoxin B1