Advanced Quantification of Trans Fatty Acids in Biscuits Using Fourier Transform Infrared Spectroscopy with Attenuated Total Reflectance (FT-IR-ATR)

Abstract

The aim of the present study was to investigate the feasibility and applicability of Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FT-IR) techniques, without extraction, with prior extraction of fat and after hydrolysis and methylation, to fatty acid methyl esters (FAMEs) to evaluate the content of trans fatty acids (TFA) in filled biscuits and to compare the results obtained with those obtained when elaidic acid was determined by the GC-MS technique. Eight commercial brands of chocolate filled biscuits and one package of hydrogenated vegetable fat were selected to be used as secondary standards by ATR-FT-IR. The presence of TFA was identified by ATR-FT-IR by visualization of the band at 966 cm-1. No significant differences were found between the concentrations of TFA determined by the three methods tested. The study indicated that the ATR-FT-IR technique, when used to analyze the lipid extract and the samples in the form of FAMEs, is suitable for estimating the TFA content in chocolate filled biscuits.