For the frying processing, samples were fried at approxi-
mately 180 C using soybean oil for an average of 30 min and then
drained on absorbent paper. For breads, including both industrial
and traditional, samples were dried in an oven at 60 C for 24 h;
before and after heating, samples were weighed and the ratio of
two measurements were considered for
final calculation of total
nitrate/nitrite content. Table 1 provides detailed descriptions of
food samples preparation.