Effect of lactic and citric acid on the stability of B-aflatoxins in extrusion-cooked sorghum

Abstract

To evaluate the effect of the extrusion-cooking process with the addition of different acids concentration on the stability of B-aflatoxins in sorghum. Experimental units (EU) of sorghum flour contaminated with B-aflatoxins (140 ppb) were extrusion cooked with aqueous lactic or citric acid at six different concentrations. The effects of the two extrusion variables (moisture content and acid concentration) were analysed as a completely randomized factorial 3 x 6 design. Under some conditions, the aflatoxin reduction is more effective when using aqueous citric acid (up to 92%), than when using aqueous lactic acid (up to 67%). With citric acid, some extrusion treatments produced higher aflatoxin degradation rates, than those produced with lactic acid. Aflatoxin contamination is a great risk both for human as well as for animal health in underdeveloped countries; consequently, practical and economical detoxification procedures are needed that eliminate or at least minimize the aflatoxin risk, through lowering aflatoxin concentrations in grains. Under these considerations, extrusion process can be used for reduction in the aflatoxin content in contaminated grains.