Assessment of Nitrate Concentration in Some Leafy Vegetables in Brack Alshatti Local Market

Abstract

This study aimed to determine the concentration of nitrate content in eleven different leafy
vegetables collected from the Brack local market in Brack during the year 2023. These leafy
vegetables include chard, dill, parsley, lettuce, Spanish, coriander, salad rocket, chives, white
cabbage, red cabbage, and Lactuca sativa. Nitrate was determined using the spectrophotometer
method; the nitrate concentration was 235.97–249.54, 235.84–238.59, 235.57–249.26, 237.28–
249.22, 237.58–245.81, 236.91–241.07, 236.40–247.26, 237.71–24.23, 237.58–238.10, 237.06–
249.39, and 236.94–249.23 mg/kg dwt. Their nitrate concentration (mean ± SD) mg/kg dwt. was
245.15±4.06, 242.19±3.81, 240.94±4.73, 240.56±3.72, 240.8±3.13, 239.36±1.43, 237.75±0.85,
243.4±3.86, 237.92±0.18, and 244.2±5.86, respectively. The highest concentration among leafy
vegetables was determined in chard (245.15±4.06 mg/kg/dwt), while the lowest nitrate
concentration was determined in dill (237.75±0.85 mg/kg/dwt). The results indicate that the nitrate
concentration in the leafy vegetables did not vary significantly. The nitrate concentration in leafy
vegetable samples was lower than the permissible limits recommended by the FAO/WHO Expert
Committee on Food Additives. Multivariate statistics indicated that most vegetable samples
exhibited no correlation. Only three principal components were identified to interpret the results,
accounting for 100% of the total variation among the eleven leafy vegetables. The cluster analysis
produced a dendrogram that grouped the sampled vegetables according to their nitrate
concentration dissimilarity. This dendrogram revealed variations among the eleven vegetables
studied.