Abstract: Using ion chromatography and spectrophotometry methods to determine nitrite in milk powder according to the national standard GB 5009.33-2016 Determination of nitrite and nitrate in food. Colorimetric and injection the samples after pretreatment, good linear relationship in the range of 0.02~0.20 mg/L by 2 kinds of methods, correlation coefficient were above 0.999. Participate capability verification of determining nitrite in milk power in 2017, the detected value is within the allowable range of the capability verification reference value tested by 2 kinds of methods, Z was less than 2.0 and the results of the assessment was satisfactory, it shows that both methods were accurate and stable. Both methods can be used for the detection of nitrite in milk powder, ion chromatography has better repeatability and accuracy, and the method was superior to spectrophotometry in terms of sample preparation and environmental protection.

Key words: milk powder, nitrite, ion chromatography, spectrophotometry