FIA evaluation of nitrite and nitrate contents of liver pâtés

A comparative study on the nitrite and nitrate contents of 15 liver pâté brands, in a total of 45 samples (three batches per brand) is presented. The study was conducted on two different kind of pâtés: pork liver pâtés and fowl liver pâtés. For the simultaneous determination of nitrite and nitrate, an automated flow injection system with spectrophotometric detection was used. The manifold was based on the splitting of the flow after injection and subsequent confluence of the flow before reaching the detector, allowing the reduction of nitrate to nitrite in part of the sample plug on an on-line copper cadmium reductor column. Spectrophotometric determination was made after a diazotization coupling reaction. The levels of nitrites and nitrates ranged from 1.07 mg NaNO2 kg−1 ± 0.43 to 15.9 mg NaNO2 kg−1 ± 5.2 and from 24.5 mg NaNO3 kg−1 ± 2.7 to 207 mg NaNO3 kg−1 ± 14, respectively. The levels of concentration of these constituents were below the allowable limits. A significant dispersion in the results was observed between different brands and within some of the brands.