Fatty acids profiling of avocado seed and pulp using gas chromatography–mass spectrometry combined with multivariate chemometric techniques

Abstract

In the present study, the profiling of 17 fatty acids (FAs) in avocado seed and pulp was investigated. The fatty acids were extracted with vortex-assisted extraction, methyl esterified and finally preconcentrated by dispersive liquid–liquid microextraction. The preconcentrated fatty acid methyl esters (FAMEs) were analyzed using gas chromatography–mass spectrometry (GC–MS) to obtain qualitative and quantitative information. The GC–MS data were analyzed using multivariate curve resolution-alternating least squares (MCR-ALS) method to overcome general chromatographic problems such as overlapped peaks, background interference and peak shifts. The calibration data were prepared using pure analytical information obtained by MCR-ALS. The linear dynamic ranges and regression coefficients (R ²) for FAMEs were in the range of 0.19–65 mg L⁻¹ and 0.990–0.999, respectively. The relative standard deviation (RSD%) for determination of FAs in avocado seed and pulp was 0.17–8.84 and 0.64–17.93, respectively. The main FAs in the avocado pulp were: oleic acid (74.25 g Kg⁻¹), linoleic acid (26.87 g Kg⁻¹), palmitic acid (26.02 g Kg⁻¹), palmitoleic acid (1.22 g Kg⁻¹) and stearic acid (0.05 g Kg⁻¹). And, the main FAs in the avocado seed were: linoleic acid (1.09 g Kg⁻¹), palmitic acid (0.47 g Kg⁻¹), oleic acid (0.33 g Kg⁻¹), linolenic acid (0.12 g Kg⁻¹), and palmitoleic acid (0.04 g Kg⁻¹).