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Orientador(es)
Resumo(s)
A sequential injection analysis (SIA) system for the spectrophotometric determination of nitrate in dairy samples was developed. A test
portion was aspirated into a carrier solution containing ethylendiaminetetracetic acid (EDTA) and ammonium buffer, which flowed into
a copperized cadmium reduction column installed in-line for the determination of the nitrate plus nitrite contents of samples. For the
nitrite determination, another test portion of sample was aspirated and directly sent to the detector without reduction. Nitrate content
was calculated from the difference between nitrate plus nitrite (expressed as nitrite) and nitrite content. The spectrophotometric
determination is based on the Griess reaction. The proposed method was used to test several dairy samples (ultrapasteurized milk with
1.7% milk fat, whey, raw bovine milk and several cheese varieties). Results were statistically in good agreement with those provided by
the reference procedure, with a detection limit of 0.15 mgL 1. A sampling rate of 21 determinations per hour can be achieved with this
procedure.
Descrição
Palavras-chave
Sequential injection Copperized cadmium column Nitrate Nitrite Dairy samples
Contexto Educativo
Citação
LIMA, M.J. Reis ; FERNANDES, Sílvia M.V. ; RANGEL, António O.S.S. - Determination of nitrate and nitrite in dairy samples by sequential injection using an in-line cadmium-reducing column. International Dairy Journal. ISSN 0958-6946. Vol. 16, n.º 12 (2006), p. 1442–1447
Editora
Elsevier