Effect of Temperature and Screw Speed on Stability of Fumonisin B₁ in Extrusion‐Cooked Corn Grits

Abstract

ABSTRACT Corn grits spiked with fumonisin B 1 (FB 1 ) at a level of 5 μg/g were extrusion cooked in a corotating twin‐screw extruder at different temperatures (140, 160, 180, and 200°C) and screw speeds (40, 80, 120, and 160 rpm). Good recoveries of FB 1 were obtained from the nonextruded as well as the extruded grits by using high‐performance liquid chromatography. Both the barrel temperature and the screw speed significantly ( P ≤ 0.05) affected the extent of fumonisin reduction in extruded grits. As expected, the FB 1 recovered decreased with an increase in temperature and a decrease in screw speed. The amount of FB 1 lost from cooking grits at the different extrusion parameters used in this study ranged from 34 to 95%. About 46–76% of the spiked FB 1 was lost when the grits were cooked at temperatures and screw speeds that resulted in acceptable product expansion and color.