Determination of elevated levels of nitrate in vegetable powders by high-precision isotope dilution GC–MS. (15th July 2019)

• Record Type: Journal Article
• Authors: Pagliano, Enea; Mester, Zoltán
• Is Part Of: Food chemistry. Volume 286(2019)
• Page Start: 710
• Page End: 714
• Publication Date: 2019-07-15
• Subjects: Food safety -- Dietary nitrate -- Vegetable powders; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2019.02.048
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: Desiccation of vegetables does not impact the absolute content of inorganic nitrate. The nitrate content in vegetable powders may exceed the percent level. Consumption of vegetable powders may yield a major contribution to dietary nitrate. Abstract: A high-precision isotope dilution GC–MS method was employed for the determination of nitrate in processed vegetables. The samples were extracted in water, derivatized with triethyloxonium tetrafluoroborate and analyzed by headspace GC–MS (15 samples/h). The method was applied to estimate the effect of drying on the content of nitrate in vegetables. The absolute amount of nitrate in a spinach sample before and after drying did not change even when the material was baked at 105 °C. Elevated levels of nitrate were found in commercial vegetable powders where the nitrate mass fraction exceed the percent level: 1.2–2.3% NO3 − was found in spinach powders, 1.3–1.6% in kale powders, and 1.4% in a beetroot powder. The likely reduction of the antioxidant properties seen in vegetable powders along with their high nitrate content suggest the need to study the risk of endogenous N -nitrosation associated with these products.