建立一种使用离子色谱技术检测乳制品中亚硝酸盐和硝酸盐的方法.乳制品试样经水溶解后,使用亚铁氰化钾和硫酸锌溶液沉淀其中的蛋白质,上清液经C18柱、银柱、钠柱3种固相萃取柱净化后,进行离子色谱-电导检测器测定,使用外标法定量,然后对检测方法进行方法验证.结果表明:亚硝酸盐(以NaNO2计)和硝酸盐(以NaNO3计)含量分别在0.01～0.20 μg/mL和0.1～2.0 μg/mL内与峰面积线性良好,线性相关系数(R2)≥0.99,定量限分别为0.2、0.4 mg/kg,加标回收率为92.5%～102.0%,相对标准偏差为1.5%～6.6%.该方法结果准确、重复性好、操作简单,适用于乳制品中亚硝酸盐和硝酸盐的测定.
An ion chromatography with conductivity detector(IC-CD)method was developed for the determination of nitrite and nitrate in milk products.Samples were dissolved in water and added with potassium ferrocyanide and zinc sulphate solutions for protein precipitation.The supernatant was cleaned up on C18,Ag,and Na solid-phase extraction(SPE)columns,and analyzed by IC-CD.An external standard method was used for quantification.The IC-CD method was validated.Good linearity between the concentrations of nitrite(NaNO2)and nitrate(NaNO3)in the range of 0.01-0.20 mg/L and 0.1-2.0 mg/L,respectively and peak area was observed with correlation coefficient equal to or higher than 0.99.The limits of quantitation for nitrite and nitrate were 0.2 and 0.4 mg/kg,respectively.The spiked recoveries ranged from 92.5%to 102.0%,and the relative standard deviation(RSD)for precision from 1.5%to 6.6%.This method is accurate,repeatable,simple and applicable to the determination of nitrite and nitrate in milk products.
印杰;郑国建;叶寅颖
上海市质量监督检验技术研究院,上海 200233
轻工业
乳制品;亚硝酸盐;硝酸盐;离子色谱
milk products;nitrite;nitrate;ion chromatography
《乳业科学与技术》 2024 (001)
14-18 / 5
上海市科学技术委员会科研计划项目(22DZ2202400)
10.7506/rykxyjs1671-5187-20240401-014
评论