【作者】 常敬华；

【导师】 刘阳；

【作者基本信息】 中国农业科学院 ， 农产品质量与食物安全， 2014， 博士

【摘要】 脱氧雪腐镰刀菌烯醇（DON）属B族单端孢霉烯族毒素，主要由禾谷镰刀菌和黄色镰刀菌产生，是世界上分布最广泛的真菌毒素之一，因其具有急性毒性、慢性毒性、细胞毒性、免疫毒性等多种毒性作用而严重影响人和牲畜的健康。DON毒素可通过污染的小麦、大麦、玉米等原料进入食品和饲料中。另外，家畜和家禽食用污染的饲料会使DON毒素少量进入牛奶、肉和蛋中从而间接影响人类健康。因此，分析食品加工中DON毒素含量的变化规律，探讨合理的加工方法降低DON毒素的含量，成为降低DON毒素危害的重要方法及合理评估其危害的重要手段。1.采用9个不同污染程度（DON）的小麦面粉为材料加工及煮制挂面，和面时分别添加0、0.3%、1.0%碳酸钠，检测湿挂面、干挂面及煮制后DON含量。结果表明挂面煮制可有效去除DON，无碱及碳酸钠为0.3%时，两种挂面加工及煮制DON毒素的去除效果均无显著差异，DON毒素的去除只发生在煮制过程，主要原因为DON毒素在汤中的溶解；碳酸钠添加量为1.0%时，干燥及煮制对DON毒素有去除效果，其DON的去除率高于其余两种挂面，主要为DON毒素在汤中溶解及热和碱的作用导致降解。通过DON标准品与碳酸钠溶液的加热反应，通过HPLC和Q-TOF检测发现DON毒素在碳酸钠溶液中可产生6种已知产物C15H20O6(iso DON, lactone DON)、C15H20O5（nor DON D）、C14H18O5（norDONA, B, C），其毒性显著降低。2.分别采用0-1.0%的碳酸钠添加量及40℃、50℃、60℃、70℃温度下对湿挂面进行干燥及挂面煮制，分析DON的去除效果，结果表明：1%碳酸钠添加量，70℃干燥的挂面加工及煮制，其DON毒素的去除效果远高于低温或无碱挂面加工及煮制的挂面。1%碳酸钠，70℃条件干燥挂面可将DON毒素由1.92mg/kg降至国家标准（1mg/kg）；干燥后再煮制可将DON毒素由4.50mg/kg降至国家标准。添加1%碳酸钠，高温干燥显著增加了挂面干燥及煮制对DON毒素的去除效果。3.通过采用不同碱含量加工DON毒素污染的面条并蒸制，分析DON毒素去除效果，水分含量为38%，加碱量为0.35%时，蒸制后DON毒素含量预测曲线为y=0.8203x-0.0982，R2=0.9947，可将DON毒素含量由1.34mg/kg降至国家标准；碱的加入在一定程度上促进了DON毒素的降解，优于无碱挂面蒸制。4.通过煮制水中加入碳酸钠判断对DON毒素去除效果，0.25%碳酸钠浓度煮制挂面对熟挂面无显著不良影响，且具有一定的毒素去除作用。水中加入0.25%碳酸钠煮制挂面后，获得DON毒素去除的预测曲线y=0.4546x-0.0377，R2=0.9605，通过曲线可知，加碱煮制面条可将DON毒素含量由2.30mg/kg降至国家标准，显著了的增加了煮制对DON毒素的去除效果。5.通过采用自然污染DON的小麦面粉进行面包加工，分析面包加工过程及还原性添加剂对DON毒素的影响，结果发现：发酵结束后，面团中DON毒素含量与原始面粉相比变化不显著；烘烤结束后，面包皮中DON毒素的含量降低7.9%-15.1%，面包囊中DON毒素的含量降低7.4%-17.1%，但面包皮与面包囊中DON毒素含量无显著差异，证明美拉德反应对DON毒素无显著降解作用；面包加工中添加抗坏血酸(200mg/kg)、L-半胱氨酸(60mg/kg)、L-谷胱甘肽(60mg/kg)后，还原性添加剂在面包发酵过程及烘烤过程中对DON毒素均无显著降解作用。更多还原

【Abstract】 Deoxynivalenol (DON) is a natural-occurring mycotoxin which belongs to a wide family ofmycotoxins known as trichothecenes produced by several Fusarium species, mainly F. graminearumand F. culmorum. It is a significant contaminant due to its frequent occurrence in toxicologicallyrelevant concentrations worldwide. DON affects animal and human health causing acute toxicity andimmunotoxicity. In addition, livestock and poultry consumption of the DON contaminated feed, it ispresent in small amount in the milk, meat and eggs and thus indirectly affect human health. Since therate of the occurrence of DON in wheat is high, effective procedures to remove or eliminate DON fromfood products is essential to minimize exposures in those who consume large amounts of wheat.1. The present study analyzed the level of DON removal in different noodle making processes andits content was determined in the processed and cooked noodles. Nine different DON contaminatedwheat flours were used as raw materials in the noodle making process. During the kneading of thedough, sodium carbonate was added at0,0.3%and1%, and the level of DON was detected in wet, dryand cooked noodle. The results showed that cooking is a effective way of removing DON, reduction ofDON content in1%sodium carbonate was higher than the other two kinds of noodle. No significantdifference in the non-alkaline and0.3%alkaline noodle. Presence of1%sodium carbonate in the wetand dry noodle had brought some changes in DON concentration. Boiling DON in0.3%sodiumcarbonate solution could generate a new product and its molecular structure needs further evaluation.2. To analyze the reduction of DON in the dried noodles and cooked noodles by different sodiumcarbonate concentration and different drying temperature. The results showed that the reduction of DONin the noodles processing and cooking by1%sodium carbonate added and dried at70°C was higherthan low temperature dried noodles and no alkaline noodles and the content of DON in the dried noodlecan be reduced from1.92mg/kg to the maximum tolerable limits of DON in China. After noodles werecooked, DON can be reduced from4.50mg/kg to national standards. Added1%content sodiumcarbonate and dried by high-temperature significantly increased reduction of DON.3. To analyze the reduction of DON after noodles steamed by using different processing of DONcontamination. The results showed that if the alkaline content was0.35%and the water content was38%, The prediction curve of DON in steamed cooked noodles was y=0.8203x-0.0982, R2=0.9947.The DON content reduced from1.34mg/kg to the maximum tolerable limits of DON in China aftersteaming. The alkaline condition played an important role in the reduction of DON.4. To determine of reduction of DON, contaminated noodles was cooked by alkali water. TheDON content predicted curve by the0.25%sodium carbonate cooked was y=0.4546x-0.0377, R2=0.9605. From the curve, the DON can be reduced from2.30mg/kg to the maximum tolerable limits ofDON in China after noodles was cooked in alkali water. The alkaline significant increased the reductionof DON. 5. Deoxynivalenol (DON) contaminated wheat was used in making bread and the role of breadprocessing and bread additives on deoxynivalenol reduction was analyzed. The results showed that afterfermentation, no significantly difference in the DON content from the original flour was observed. Afterbaking, the DON reduction in bread crust is7.95%to15.08%, and the DON reduction in inner parts ofbread is7.39%to17.06%. The content of DON in bread crust had no significant difference from innerparts of bread. Maillard reaction had no significant influence on the reduction of DON content. Theadditives Vc (200mg/kg), L-cysteine hydrochloride (60mg/kg), and glutathione (60mg/kg) had nosignificant impact on the DON reduction in bread fermentation and baking process.更多还原