Determination of Organic Acids in Brassica Rapa L. Leaves (Turnip Greens and Turnip Tops) Regulated by the Protected Geographical Indication “Grelos De Galicia”

Resumo

A rapid high-performance liquid chromatographic method for the determination of organic acids in Brassica rapa L. leaves is reported. Under optimum conditions the detection limits were between 0.26 to 8.00 µg/mL and quantification limits were between 0.28 to 12.50 µg/mL. The precision results showed that the relative standard deviations of repeatability and reproducibility were ≤ 0.84% and ≤ 1.49%, respectively. The recovery of the organic acids varied from 97.21 to 99.57%. Organic acids were determined in 44 samples of Brassica rapa var. rapa L. protected under the PGI “Grelos de Galicia” in the two plant status (turnip greens and turnip tops). The results showed that all of the samples presented a profile composed of at least four organic acids: citric, malic, oxalic, and ascorbic acids. However, these organic acids were present in different concentrations in turnip greens and turnip tops.