PL
Przedstawiono wyniki badań zawartości azotanów i azotynów w zbiorczym mleku surowym, serach twarogowych i serach twardych dojrzewających z obszaru całej Polski. Do oznaczeń stosowano metodę opartą na reakcji Griessa, po uprzedniej redukcji azotanów do azotynów za pomocą aktywnego kadmu metalicznego. Stwierdzone stężenia azotanów i azotynów nie budzą poważniejszych zastrzeżeń toksykologicznych.
EN
During 1994-1995 nitrates and nitrites in 94 samples of raw milk, 111 samples of curdy cheese and 96 samples of rennet cheese were determined. The samples were collected in all regions of Poland. The concentration of nitrates and nitrites was determined by spectrophotometry after Griess reaction. Some levels of nitrates were detected almost in all (>95%) samples of milk and cheese. Mean nitrate concentration in raw milk and curdy chesse was 4.53 and 3.19 mg NaNO3/kg respectively. Mean level of nitrate in rennet cheese was higher, 17.41 mg NaNO3/kg. Nitrites were detected only in some samples of milk (6.3%) and rennet cheese (35.4%). The concentrations of nitrites were below 2.0 mg NaNO2/kg. The levels of nitrates and nitrites in milk and cheese were relatively low and not harmful to the health of the consumers.