Reduction of fumonisin B1 in corn grits by single-screw extrusion

This study was designed to determine the efficacy of extrusion in reducing fumonisin 131 in corn flaking grits in the presence and absence of glucose. In addition, degradation products of fumonisin 131 during extrusion were identified and quantitated with a mass balance approach. Uncontaminated clean corn grits, grits spiked with 30 mu g/g fumonisin B-1, and grits fermented with Fusarium verticillioides M-2552 (40-50 mu g/g fumonisin B-1) were extruded in the presence and absence of glucose (10%, w/w) using a single-screw extruder. Extrusion decreased fumonisin B-1 by 21-37%, whereas the same process with added glucose further decreased fumonisin B, by 77-87%. LC-fluorescence and LC-MS showed that most fumonisin in the extruded samples without added glucose was the fumonisin 131 form, whereas the main degradation product in grits extruded with glucose was N-(deoxy-D-fructos-1-yl)fumonisin B-1. The formation of hydrolyzed fumonisin B, was not significant during extrusion. Results suggest that extrusion in the presence of glucose may reduce fumonisin B-1 in corn grits significantly.