Gentle debranning as a technology to reduce microbial and deoxynivalenol levels in common wheat (Triticum aestivum L.) and its application in milling industry

In order to improve the hygienic characteristics of the wheat kernels and flours, gentle debranning technology was employed in this study. The physical, chemical and microbial modifications associated with the debranning of common wheat at a peeling rate of 0???5% were examined. Results showed that 80.1% of microorganisms and 15.82% of deoxynivalenol were removed when 1.08% of the total weight of the grain was peeled. The breakage rate of wheats increased from 0.23% to 0.38%, and there was no significant difference in hardness index compared with unpeeled kernels. Microstructure analysis showed an evenly removal of majority of outer pericarp (thickness of 25???35 ??m), while the middle layer and aleurone layer remained intact. A further increase of debranning level led to moderate reduction of contamination but the mechanical strength of kernels decreased sharply. Therefore, gentle debranning at a peeling rate of 1.08% was deemed appropriate for milling industry. A significant decrease in ash content was observed for the three commercial flours, which could generate economic benefits. At the same time, the microbial contents of wheat products decreased by 23.0%???41.3%, and the deoxynivalenol contents decreased by 11.78%???20.75%. This study demonstrated the possibility of employing gentle debranning for reducing contaminants in wheat without compromising the milling characteristics.