Comparison of different extraction methods for the determination of fatty acid methyl esters in mussles samples

The profiling of fatty acids (FAs) involves an analytical approach that offers detailed information regarding the qualitative
and quantitative distribution of FAs in food products. This technique, when combined with high-capacity analytical
methods, aids in addressing numerous questions related to the nutritional quality and authenticity of food. In natural
samples, FAs are primarily found in esterified forms as triglycerides, necessitating their conversion into fatty acid methyl
esters (FAMEs) prior to gas chromatography analysis for precise profiling. Prior to any derivatization reaction, lipid
extraction from complex matrices, apart from pure fats and oils, is necessary. In this work, three methods for the
extraction and derivatization of FAMEs are used. In particular, the fatty acids profile obtained with the microwaves-
assisted extraction and derivatization (MAED) was compared with the one obtained from the conventional FAMEs
preparation method. The microwave-assisted method proved to be fast, simple, and effective for analysing complex
samples like mussels. The FAMEs were subsequently analysed using reversed fill/flush differential-flow modulation
comprehensive two-dimensional gas chromatography (GCxGC) coupled with flame ionization detection (FID) to identify
and quantify individual fatty acids. GCxGC analysis offers superior separation power compared to one-dimensional GC
and generates structured chromatograms based on the chemical patterns, enhancing the reliability and accuracy of
identification. Additionally, the environmental impact of the method was evaluated based on the recently published
PrepAGREE criteria, demonstrating superior performances compared to official methods in terms of greenness.