Determination of olive oil acidity by CE


Autoria(s): Balesteros, Manoela R.; Tavares, Marina F. M.; Ribeiro, Sidney José Lima; Polachini, Ferminio C.; Messaddeq, Younes; de Oliveira, Marcone A. L.
Contribuinte(s)

Universidade Estadual Paulista (UNESP)

Data(s)

20/05/2014

20/05/2014

01/10/2007

Resumo

In this work, a CE method for the determination of olive oil acidity was proposed. The method was based on an ethanolic extraction (at 60 degrees C) of the oil long-chain free fatty acids (LC-FFAs) components followed by CE determination in pH 6.86 phosphate buffer at 15 mmol/L concentration containing 4 mmol/L sodium dodecylbenzenesulfonate (SDBS), 10 mmol/L polyoxyethylene 23 lauryl ether (Brij 35((R))), 2% v/v 1-octanol and 45% v/v ACN under indirect UV detection at 224 nm. Although this electrolyte promoted baseline separation of myristic acid (C14:0) (internal standard (IS)) and olive oil major components (palmitic acid (C16:0), oleic acid (C18:1c) and linoleic acid (C18:2cc)) in less than 8 min, after a few injections, the electropherogram profiles were severely altered (peak broadening, migration time shifts, etc.) and the current increased substantially. An adsorption study was conducted revealing that the dissolution of the capillary external polyimide coating during the electrophoretic run caused the detrimental effect. After removal of the capillary tip coating, ten consecutive injections could be performed without any disturbances and this simple procedure was, therefore, implemented during quantitative purposes. The reliability of the proposed method was further investigated by the determination of acidity of an extra virgin olive oil sample in comparison to the established methodology (AOCS method Ca 5a40, alkaline volumetric titration (AVT)). No statistical differences were found within 95% confidence level. A % acidity of 0.39 +/- 0.02 was found for the olive oil sample under consideration.

Formato

3731-3736

Identificador

http://dx.doi.org/10.1002/elps.200700507

Electrophoresis. Weinheim: Wiley-v C H Verlag Gmbh, v. 28, n. 20, p. 3731-3736, 2007.

0173-0835

http://hdl.handle.net/11449/37862

10.1002/elps.200700507

WOS:000250657100018

Idioma(s)

eng

Publicador

Wiley-Blackwell

Relação

Electrophoresis

Direitos

closedAccess

Palavras-Chave #CE #long-chain free fatty acids #olive oil acidity determination
Tipo

info:eu-repo/semantics/article