Effect of nixtamalization (alkaline cooking) on fumonisin-contaminated corn for production of masa and tortillas

Studies were undertaken to determine the fate of the mycotoxins, fumonisins, during the process of alkaline cooking (nixtamalization), using normal-appearing corn that was naturally contaminated with fumonisin B-1 (FB1) at 8.79 ppm. Corn was processed into tortillas, starting with raw corn that was cooked with lime and allowed to steep overnight; the steeped corn (nixtamal) was washed and ground into masa, which was used to make tortillas. Calculations to determine how much of the original fumonisin remained in the finished products took into consideration that FB1 will be converted to hydrolyzed fumonisin B-1 (HFB1) by the process of alkaline cooking. All fractions, including steeping and washing water, were weighed, and percent moisture and fumonisin content were determined. Tortillas contained approximately 0.50 ppm of FB1, plus 0.36 ppm of HFB1, which represented 18.5% of the initial FBI concentration. Three-fourths of the original amount of fumonisin was present in the Liquid fractions, primarily as HFB1. Nixtamalization significantly reduced the amount of fumonisin in maize.