[Occurrence of nitrates and nitrites in certain frozen fruits, jams, stewed fruit and fruit-vegetable juices for children and in certain types of bee honey]

Abstract

Nitrates and nitrites were evaluated spectrophotometrically by the method of Griess reaction, with previous reduction of nitrates to nitrites in a column filled with cadmium dust. The content of nitrates in frozen fruit (strawberries, black and red currant and plums) ranged from 2.50 to 57.38 mg KNO3/kg, with the highest content in garden strawberries. In cherry, strawberry, black and red currant jams the concentrations were from 6.30 to 97.38 mg KNO3/kg, the highest content was in cherry jam. In plum jam nitrates were found in low amounts from 11.65 to 12.09 mg/kg. In "Bobofrut" juices the nitrate content was higher than in the above products, ranging from 26.37 to 182.75 mg KNO3/kg. Nitrite content in all these groups of products was low, not exceeding 1 mg NaNO2/kg, with the exception of plum jam where the maximal value was found 1.65 mg NaNO2/kg. In stewed fruit and herb syrups and in honey nitrates ranged from 1.0 to 94.5 mg KNO3/kg. Nitrite content ranged from 0.17 to 1.92 mg/kg in herb syrups, from 0.0 to 1.20 mg/kg in stewed fruit, and from 0.0 to 0.40 mg NaNO2/kg in honey. The study showed that higher levels of nitrates were present as a rule in vegetable juices. However, the found concentrations were not harmful to the health of children, although this is possible in the case of carrot juice, especially when kept at room temperature for 24 hours.