Effect of ripening in nitrates and nitrites contents in semihard cheeses

Abstract

Six batches of cheese, three of Chanco and three chilean Gauda with different additions of NaNO₃ to milk (0.015%, 0.02% and 0.03%) were studied. Cheese was stored at 10 to 12°C, during ripening, with a relative humidity of 85% to 90%. Nitrate and nitrite contents were determined by the method of cadmium reduction and photometry at 0, 3, 6 and 9 weeks of ripening. Also samples of semihard cheese were picked up, at random, from the market for the same analysis.
The nitrate contents reduction in Chanco and Gauda cheese manufacturad with different treatments of addition of NaNO₃ has exponential shape, being most evident in Chanco cheese.
Contents of nitrate market cheese samples Chanco, Chanco de campo and Gauda, was under the limit recommended by FAO/WHO (50 mg/kg). With mathematical functions describing the reduction of nitrates in cheese is possible to calculate residues in Chanco cheese.