Tanaka A, Nose N, Masaki H, Kikuchi Y, Iwasaki H
J Assoc Off Anal Chem. 1983 Mar;66(2):260-3.
A simple, sensitive, and practical method is described for determination of nitrite in egg, egg white, and egg yolk. Egg is deproteinized by adding a mixture of ammonium thiocyanate, mercuric chloride, and zinc acetate, and centrifuged. Nitrite in the supernate is converted to tetrazolophthalazine by reaction with hydralazine in acidic solution and then determined by gas-liquid chromatography with an electron-capture detector (GLC-ECD) and a column of OV-225 on Chromosorb W(HP). Nitrite concentrations from 5 to 50 ng/mL are calculated from peak height; the detection limit is 3 ng/mL extract. Recoveries from eggs, egg whites, and egg yolks ranged from 91.7 to 98.0%. The mean nitrite concentration in 50 egg samples was 0.04 ppm (0.01-0.11 ppm) with a detection limit of 4 ng nitrite/g.
本文描述了一种简单、灵敏且实用的方法，用于测定鸡蛋、蛋清和蛋黄中的亚硝酸盐。通过加入硫氰酸铵、氯化汞和醋酸锌的混合物使鸡蛋脱蛋白，然后离心。上清液中的亚硝酸盐在酸性溶液中与肼反应转化为四唑酞嗪，然后用带电子捕获检测器（GLC - ECD）和Chromosorb W(HP)上的OV - 225柱的气液色谱法进行测定。根据峰高计算出5至50 ng/mL的亚硝酸盐浓度；检测限为3 ng/mL提取物。鸡蛋、蛋清和蛋黄的回收率在91.7%至98.0%之间。50个鸡蛋样品中亚硝酸盐的平均浓度为0.04 ppm（0.01 - 0.11 ppm），检测限为4 ng亚硝酸盐/克。
