Development of a headspace solid-phase microextraction gas chromatography–mass spectrometric method for the determination of short-chain fatty acids from intestinal fermentation

The determination of short-chain fatty acids produced by colonic fermentation can provide useful information as a tool to evaluate prebiotic effects of foods with beneficial effects on human health. In this study, we developed and validated a headspace solid-phase microextraction gas chromatographic–mass spectrometric method for the determination of underivatised short-chain fatty acids produced in an in vitro fermentation model. A divinylbenzene/Carboxen/polydimethylsiloxane fibre was used. Solid-phase microextraction conditions, i.e., extraction temperature, extraction time and salt addition were optimised by means of a central composite face-centred experimental design. The method was validated in terms of limit of quantification, accuracy, precision and linearity. The developed method was then applied to the analysis of short-chain fatty acids produced by the fermentation of faecal cultures derived from bread enriched with different kinds of dietary fibres.

► Development of an HS-SPME method for the extraction of short-chain fatty acids (SCFAs).
► Optimisation of the SPME conditions by an experimental design.
► Validation of the method (limit of quantification, linearity, precision, and accuracy).
► Determination of SCFAs produced from fermentation of bread enriched with dietary fibre.