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Técnicas analíticas aplicadas a la determinación de compuestos aromáticos en alimentos vegetales

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Abstract

El estudio del aroma de un alimento resulta relativamentedifícil, dada la gran complejidad y a la pocainformación que existe sobre este tema comparado con otros de la química de alimentos. La razón fundamental de esto es que los compuestos volátiles responsables del aroma se caracterizan por presentar una gran complejidad y variedad de estructuras químicas y por encontrarse en muy pequeña concentración. En este artículo se realiza una revisión actualizada de las distintas técnicas de extracción de volátiles: des ti !ación, extracción con solventes (continua y discontinua), extracción con tluidos supercríticos. extracción-destilación y técnicas de espacio de cabeza (estático y dinámico), seguido de análisis de la fracción volátil por cromatografía de gases (tipo de columna y naturaleza del relleno, gas portador y tipo de detector utilizado) y su aplicabilidad a alimentos vegetales. The study of flavour in food is difficult due to these compounds have received relatively little attention regarding with other food components. This review aims to present the curren! state of the different analytical techniques applied to the extraction of volatile compounds: distillation, solvent extraction (continous and discontinous), steam distillation-solvent extraction, extraction with supercritical fluids, headspace methods (static and dynamic), followed by gas chromatographic analysis of the volatile fraction (type of column, carrier gas. type of detector). A great number of references about volatile analysis in food vegetables is given.
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... Sampling and sample preparation (extraction, preconcentration, fractionation and isolation) are the steps that normally require the most time during the analytical procedure (Kataoka, Lord, & Pawliszyn, 2000;Maslamani, Manandhar, Geremia, & Logue, 2016). Sample preparation is a critical step, since a large amount of analyte can be lost and lead to significant errors (Andrade-Eiroa, Canle, Leroy-Cancellieri, & Cerdà, 2016a; Rodríguez-Bernaldo de Quirós, González-Castro, López-Hernández, & Simal-Lozano, 1996). Therefore, it is not an exaggeration to say that a good choice of the sample preparation procedure influences the analysis reliability and precision. ...
... Sample preparation techniques are based on different physicochemical properties of the analytes, such as their volatility, solubility in different organic phases, and their ability to be absorbed on a particular material. According to these properties, some extraction techniques can be classified as (Castro-Mejías et al., 2008;Rodríguez-Bernaldo de Quirós et al., 1996;Serrano de la Hoz, 2014): ...
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