可见分光光度法测定惠州梅菜中亚硝酸盐含量的方法

Visible Spectrophotometric Determination of Nitrite in Huizhou Preserved Vegetable

通过对国标《食品中亚硝酸盐与硝酸盐的测定》（GB/T 5009.33-2010）第二法进行研究和优化,建立了惠州梅菜中亚硝酸盐的检测方法.研究表明：亚硝酸盐含量x（μg）与吸光度A在538 nm处具有良好的线性关系,在亚硝酸盐的量为0～10μg· （50mL）^-1水溶液中,服从Beer定律,y=46.708x-0.024,相关系数为0.999 9.蛋白质沉淀剂的使用量对惠州梅菜中亚硝酸盐含量测定有一定影响,添加量为2～3.5 mL时,回收率在98.8％～103％之间,回收效率较理想.沉淀剂添加量为2.5mL时,进行方法加标回收试验,平均加标回收率在98.8％～98.9％之间,RSD在1.03％～4.70％之间.

Detection of nitrite content by changing dosage of protein precipitators was studied according to method 2 of detection of Nitrite and Nitrate in Foods （ GB 5009.33--2010）.The results showed that the calibration graph for aqueous procedure was obtained by plotting absorbance values at 538 nm against nitrite concentration. Beer＇s law was obeyed over the range 0-10 p,g of nitrite in an overall aqueous volume of 50 mL. The calibration graph is a straight line, obeying equation y = 46.708x-0.024, where y is the absorbanee and x （μg） is the amount of nitrite, with correlation coefficient R2=0.999 9. The dosage of protein precipitators had certain influence on detection of nitrite content. The recovery reached to 98.8%-103% when dosage was 2 to 3.5 mL.The mean recovery rate was 98.8%-98.9% and the RSD was 1.03%-4.70% when dosage was 2.5 mL.