分光光度法同时测定肉制品中的硝酸盐和亚硝酸盐

[目的]探讨更适用于实际肉制品分析的分光光度法,用于测定肉制品中硝酸盐和亚硝酸盐的含量。[方法]以氨基磺酸去除亚硝酸盐后在波长210 nm处直接测定肉制品中的硝酸盐含量,采用盐酸萘乙二胺偶合法在波长538 nm处测定肉制品中亚硝酸盐含量。[结果]在0.1~1.0 mg/L范围内硝酸盐线性关系良好,相关系数为0.999 9,样品在0.20、0.30和0.50 mg 3个添加水平的平均回收率为98.91%(RSD为1.32%),检出限0.04 mg/L。在0.1~2.0 mg/L范围内亚硝酸盐线性关系良好,相关系数为0.999 7,样品在0.20、0.30和0.50 mg 3个添加水平的平均回收率为98.55%(RSD为0.26%),检出限0.02 mg/L。[结论]与国标方法相比,该研究方法更简单,易于操作,适用于检测机构对肉制品中大批量样品的检测工作。

Determination of Nitrate and Nitrite in Meat Products by UV Spectrophotometry

[ Objective] To study the content determination method of nitrate and nitrite in meat products by UV spectrophotometry. [ Method] The nitrate content was determined by UV spectrophotometry at 210 nm after masking nitrite with aminosulfonic acid. The nitrite content was de- termined by UV spectrophotometry at 538 nm after conjugate with N -（ 1 -naphthyl） -ethylenediamine dihydrochloride. [ Result] The linear ran- ges of nitrate and nitrite were 0. 1 -1.0 and 0. 1 -2.0 mg/L, respectively. The average recovery of nitrate and nitrite were 98.91% and 98.55%, respectively. The method with the limits of detection of 0.04 mg/L for nitrate and 0.02 mg/L for nitrite. [ Conclusion] Compared with the determination method of nitrate and nitrite by spectrophotometry in national standards, this method is simplicity, high sensitivity and good re- producibility, h is suitable for the determination of nitrate and nitrite in meat products.