Hplc–uv and Gc–ms Characterization of the Flavonol Aglycons Quercetin, Kaempferol, and Myricetin in Tomato Pastes and Other Tomato-based Products

The amounts of three flavonoids, quercetin, kaempferol, and myricetin, in tomatoes (Solanum lycopersicum L.) and tomato-based products produced in Turkey has been determined by reversed phase high-performance liquid chromatography (RPHPLC) with UV detection. The HPLC profiles of five types of tomato, one commercial composite tomato juice, and three types of tomato paste, were obtained after acid hydrolysis and extraction. The presence of the flavonol aglycons was confirmed by gas chromatography with mass spectrometric detection (GC–MS). Tomatoes and tomato-based products contained primarily quercetin, kaempferol, and the minor flavonol myricetin. The total flavonol aglycon content of different varieties of tomato varied from 3.1 to 10.0 mg kg of fresh weight. Tomato juice and tomato salsa were rich in total flavonols, containing 19.8 mg L and 10.5–13.2 mg kg, respectively. The method enabled accurate and reproducible quantitative analysis of these flavonols in tomatoes and tomato-based products.