Contents of nitrites and nitrates during the production cycles of Edam cheese

The aim of our study was to observe the contents of nitrates and nitrites during the six stages of manufacture of Edam cheese. Samples were taken of raw milk, of pasteurized milk, of milk with nitrates added, of pressed cheese curd, of whey, of ripening cheese and the final product. The samples were drawn from a commercial operation in cheese factory in the eastern part of Slovakia. The mean natura NaNO₂ content in raw and pasteurized milk was 0.10 and 0.13 mg/kg, respectively. The mean natural NaNO₃ content in raw and pasteurized milk was 0.60 and 0.66 mg/kg, respectively. In milk with nitrate added the mean content was 96.58 mg/kg NaNO₃; the maximum value being 105.54 mg/kg NaNO₃. After pressing, the mean value of nitrate was found to be 15.45 mg/kg NaNO₃. A considerable quantity of nitrates passed into the whey, where the mean nitrate content was 76.58 mg/kg NaNO₃. The final product had a markedly decreased content of nitrates (1.69 mg/kg NaNO₃) and nitrites (0.61 mg/kg NaNO₂) when compared with the values in cheese during maturation (7.92 mg/kg NaNO₃ and 1.69 mg/kg NaNO₂).