Study On The Reduction Of Deoxynivaienol (DON) During The Wheat Processing

As one of the Trichothecene mycotoxins, Deoxynivalenol （DON） frequently occurs in cereals suchas wheat, barley, and maize that are used as raw materials for food manufacture throughout the northernChina, and it’s hazardous extremely. The research aimed at removing the deoxynivalenol thoughdifferent wheat processing methods from the dirty wheat to the products, and reducing the extent of itentering the food chain, so as to ensure the human health.The samples for the study were collected at two provinces in the south of China near the HuaiRiver. By these samples, we researched the removal efficiency of different wheat processing methods atexperimental ang industrial levels, including wheat cleaning process, wheat milling process, whearlayered milling process and wheat gluten extracting process. And also, we researched the DONdistribution rule in the wheat.1. The effect of DON removal in the wheat cleaning process was analyzed by detecting the DONconcentration of wheat and its impurities collected at different steps in the wheat cleaning process fromthe flour mill. During the wheat cleaning process, the concentration of DON was reduced from2.07μg/g in dirty wheat to1.65μg/g in cleaned wheat, which accounts for20.16%reduction of DON inwheat, and removed72.62g DON which existed in3174.50kg of impurities. The efficiency of thecleaned wheat cleaning stage to remove the DON was1.67times higher than the dirty wheat cleaningstage. When the wheat passed through scouring and brushing machine, followed by closed circuitaspirator, the reduction of DON was higher, as the DON concentration was reduced from1.83μg/g to1.71μg/g in the wheat. Among all the wheat cleaning types analyzed, pneumatic separation andscouring and brushing type were found to be the important cleaning processes for the removal of DONin wheat （accounting for55.86%,31.41%,12.72%respectically）. The grading technology could sort thedifferences between the highly contaminated and less contaminated wheat, which benefit to the removalof DON.2. The experimental milling was using9kinds of wheat contaminated by the DON naturally atdifferent levels, and the industrial milling was done in a flour mill of An Hui provience. By detectingthe DON concentration of the bran, storage and flours of different milling streams including straightflour got by the experimental wheat milling process, and flours of different milling streams collectedonline in the flour mill, so as to research the reduction effect of the wheat milling process to remove theof DON. The results: DON was removed effectively after milling process, the account of DON was30.85%⁵1.43%distributed in the flour, and mainly distributed in the epidermis of wheat.Theconcentration of DON was gradually increased from the inside to outside during the wheat endosperm.The concentration of DON in flour was decreased23.67%⁶0.31%on contrast to the wheat, and inthe reduction mill system was deceased to the most of70.27%. The DON concentration of the all theflour streams of1M and1B was blow the national standard of DON. The DON concentration betweenthe wheat and flour after milling showed a regression relationship, and the equation was y=0.498x^1.206,R²=0.991. The lower DON concentration of wheat was, the much more DON reduced after milling. In summary, the wheat milling process is a kind of effective removal process method of reducing DON inwheat.3. The layered milling process could reduce the DON concentration of wheat effectively bydedected the DON concentration of wheats and epidermis collected before and after layered milling.The lower DON concentration of wheat was, the much more DON reduced after layered milling, suchas22.88%DON was removed in the experiment. Especially, the DON centration was not highest in themost outside of the wheat, but turn to the rule of raise up fist and then decrease from the outside to theinside of the wheat.4. Wheat gluten extracting process could be efficiently and safely remove the DON of wheat, theremoval effiency was turn to100%. Moreover, by the experimental results, we concluded that DONcould not combine with proteins, which provided a theoretical basis for the reduction of the combinedfree of DON degradation.The four wheat processing methods above were proved to remove DON effectively by the resultsof the experiments. Our research finding suggests that the wheat processing methods could effectivelyremove the DON in wheat at higher level, and can be applied widely.