Determination of Nitrite in Foods by Single-Sweep Polarography

Abstract

Abstract In an acid medium, nitrite diazotized with p-rosaniline and then coupled with 8-hydroxyquinoline in a weak alkaline medium produces azo compounds. The azo compounds produce a very sensitive polarographic wave at −0.70 V (versus the saturated calomel electrode). The height of the peak is linear with the concentration of nitrite in the range of 5 × 10−9 to 5 × 10−7 g/mL. The detection limit is 3 × 10−9 g/mL. The electrochemical characteristics of the polarographic wave are also discussed. The method was used to determine nitrite in sausage. The results agree well with those obtained by spectrophotometry.