论文部分内容阅读
建立了面粉及其制品中氨基脲的液相色谱-串联质谱(LC-MS/MS)测定方法,并研究了面粉及其制品中偶氮甲酰胺降解规律及氨基脲污染水平。面粉及其制品等经0.1 mol/L HCl溶液水解,邻硝基苯甲醛衍生化,乙酸乙酯提取,正己烷脱脂后,采用LC-MS/MS测定,内标法定量。氨基脲的线性范围为0.5~100μg/L;在面粉、馒头、面包等基质中添加浓度为0.5,1.0,5.0μg/kg时,氨基脲回收率范围为89.0%~99.4%,相对标准偏差在4.8%~12%之间;氨基脲定量限为0.5μg/kg。面粉制品中氨基脲的含量与偶氮甲酰胺的添加量呈线性关系。市售面包中氨基脲的阳性检出率为92.0%,阳性样品中氨基脲污染水平为17.6~353.0μg/kg,表明目前我国面包制品中氨基脲污染状况较为严重。
A liquid chromatography-tandem mass spectrometry (LC-MS / MS) method was developed for the determination of semicarbazides in flour and its products. The degradation of azodicarbonamide and the pollution level of semicarbazides in flour and its products were studied. Flour and its products were hydrolyzed with 0.1 mol / L HCl solution, derivatized with o-nitrobenzaldehyde, extracted with ethyl acetate and defatted with n-hexane. LC-MS / MS and internal standard method were used for quantification. The linear range of semicarbazide was 0.5 ~ 100μg / L. The recoveries of semicarbazide ranged from 89.0% to 99.4% at the concentrations of 0.5, 1.0 and 5.0μg / kg in the flour, bread and bread substrates. The relative standard deviations 4.8% ~ 12%; semicarbazide quantitative limit of 0.5μg / kg. The content of semicarbazide in flour products is linear with the amount of azodicarbonamide added. The positive detection rate of semicarbazide in commercial bread was 92.0% and the level of semicarbazide in positive samples was 17.6-353.0μg / kg, indicating that the status of semicarbazide pollution in China’s bread products is more serious.