Residual nitrite and nitrate levels of frankfurters along with their shelf-life

Nitrite and nitrate levels of vacuum-packaged frankfurters from four commercial brands were tested over 145 days' storage at 3 degrees C. The use of both curing salts, KNO3 and NaNO2, was indicated by only two manufacturers on the label. However, nitrate levels from 36 to 88 mg KNO3/kg were also found in those where only nitrite was mentioned among the ingredients. A good correlation between nitrite and nitrate levels and storage rime was shown by multiple linear regression analysis. The results obtained were compared with those from frankfurters prepared in a pilot plant with different concentrations of NaNO2, alone or combined with 200 mg KNO3/kg.