Reducing deoxynivalenol content in wheat by a combination of gravity separation and milling and characterization of the flours produced

Abstract

Deoxynivalenol (DON), which is produced by Fusarium graminearum complex, seriously affects the safety of wheat. The high cost and low quality of conventional control methods have hampered the development of efficient and safe methods for reducing DON content. In the present study, wheats infected by Fusarium head blight (FHB) were separated and milled using gravity separation and a laboratory mill to obtain flours of different densities. Analysis conducted to examine the rheological properties, composition, particle size, DON content and total bacteria revealed that DON, total bacteria and α-amylase showed high concentrations in low-density flour, which also contained a weak gluten network, small particle size and low starch content. Moreover, using the gravity separation and milling methods led to 62.35% and 58.02% decrease in total bacteria and 30.85% and 32.62% reductions in the DON content, respectively. Combining the methods further reduced the total bacteria and DON by 88.40% and 63.09%, respectively, and improved the gluten index and rheological properties of the dough. In addition, removing the lowest flour fractions enhanced the safety and rheological properties. These results suggest that a combination approach can significantly decrease the mycotoxins and improve flour quality, which is a promising strategy for grain processing.