Onion cultivars with low pungency have been increasing in popularity because they are more attractive for fresh, uncooked use. The pyruvic acid amount is commonly used as a measure of onion pungency. For the first time the validation of a reversed-phase high-performance liquid chromatography method for the quantitative analysis of pyruvic acid in onion extracts was carried out. The established chromatography method based on the use of a 50 mM phosphate buffer (pH 2.5) eluent system provided good precision (RSD% in the range of 1.25-1.29, in the long-period) and accuracy (recovery% in the range of 97.70-111.62, in the long-period) as well as appreciably low limit of detection and limit of quantitation values (11.03 and 33.41 ng/mL, respectively). The validated method proved successful in the analysis of the onion extract from Dorata di Parma cultivar after a preliminary solid-phase extraction step. A significant adherence with results from previous spectrophotometric determinations turned out.
Quantitative evaluation of the pyruvic acid content in onion samples with a fully validated high-performance liquid chromatography method
IANNI, FEDERICA;MARINOZZI, Maura;SARDELLA, Roccaldo;NATALINI, Benedetto
2016
Abstract
Onion cultivars with low pungency have been increasing in popularity because they are more attractive for fresh, uncooked use. The pyruvic acid amount is commonly used as a measure of onion pungency. For the first time the validation of a reversed-phase high-performance liquid chromatography method for the quantitative analysis of pyruvic acid in onion extracts was carried out. The established chromatography method based on the use of a 50 mM phosphate buffer (pH 2.5) eluent system provided good precision (RSD% in the range of 1.25-1.29, in the long-period) and accuracy (recovery% in the range of 97.70-111.62, in the long-period) as well as appreciably low limit of detection and limit of quantitation values (11.03 and 33.41 ng/mL, respectively). The validated method proved successful in the analysis of the onion extract from Dorata di Parma cultivar after a preliminary solid-phase extraction step. A significant adherence with results from previous spectrophotometric determinations turned out.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
