Optimization and validation of a simplified methodology for simultaneous extraction of fatty acids and tocopherol homologues in peanuts

Abstract

A new sample treatment methodology was developed for the simultaneous determination of oleic, linoleic, palmitic and stearic fatty acids (FA), and α-, β-, γ- and δ-tocopherol homologues in peanut samples. Usually, the determination of these compounds is carried out after oil extraction with an organic solvent at boiling temperatures of the solvent. The innovative analytical methodology developed in this work was performed in a 20 mL vial in which the FA and tocopherols were simultaneously extracted, and the derivatization of the FA was, afterwards, conducted. The reduction in analysis time from 1 h 30 min (reference methodology) to 20 min (new methodology) increased the sample throughput. Furthermore, the amount of organic solvent used decreased from 40 mL to 6 mL The new methodology was validated based on the analysis of a certified reference peanut butter sample and the results were compared to those obtained by using the reference methodology and a suitable agreement with the certified values was found. Finally, the new sample treatment approach was used to analyse toasted and fried (with and without tegument) peanuts.