一步分光光度法检测肉制品中亚硝酸盐的含量

Detection of nitrite in meat products using one-step spectrophotometry

采用引入π-共轭结构的策略,以2-硫代巴比妥酸为反应物,通过亚硝酸盐-硫醇反应,提高亚硝基的吸光度,建立一种灵敏的亚硝酸盐分光光度检测方法.研究结果表明,在0.1~10.0μg/mL的范围内,反应液的吸光值与亚硝酸钠的浓度具有良好的线性关系,相关系数大于0.99.该方法的检出限为0.02μg/mL,定量限为0.06μg/mL.利用该方法对两种市售猪肉火腿中的亚硝酸钠进行了检测,结果显示方法的回收率在85.0%~94.0%之间,相对标准偏差在1.8%~3.0%之间,两种产品中亚硝酸盐的含量分别为5.4μg/mL和4.0μg/mL,符合国家限量标准的要求(低于30 mg/kg).

In this study a sensitive spectrophotometric method for the determination of nitrite was developed by introducing aπ-conjugation structure.2-thiobarbituric acid was reacted with nitrite through the nitrite-thiol reaction,resulting in significantly enhanced absorbance.The results showed that the absorbance of the reaction mixture and the concentration of sodium nitrate had a good linear relationship in the range of 0.1~10.0μg/mL with a correlation coefficient of above 0.99.The limit of detection was 0.02μg/mL,and the limit of quantitation was 0.06μg/mL.This method was applied to the detection of sodium nitrite in two different pork hams purchased from the local market.The results showed that the recovery of this method was between 85.0%~94.0%,and the relative standard deviation was between 1.8%~3.0%.The content of nitrite in the two products were 5.4μg/mL and 4.0μg/mL respectively,which were below the national limit standard of 30 mg/kg.