Current methodologies for phytosterol analysis in foods

Plant sterols (PS) (phytosterols and phytostanols) are bioactive compounds of all vegetable foods where can be found as free sterol alcohols and as conjugates. These latter forms have been less studied, although they may have potential beneficial effects, whereas some PS have several approved health claims, especially in lowering blood cholesterol levels. In this context, it is necessary to establish analytical methods for food authentication, assessing PS health benefits and unfolding future applications. Several extraction methodologies have been employed for the extraction of PS from food matrixes (usually solvent extraction and saponification) although solid-phase extraction, solid-phase microextraction or enzymes have also been applied. In addition, the determination of PS may also need a subsequent saponification, purification or enrichment step before their determination. Gas chromatography after derivatization has historically been the method of choice for analysis, although liquid chromatography simplifies the analysis. Furthermore, although various detectors have been employed in analysing PS, mass spectrometry can address many of the challenges observed in other methodologies. Therefore, it has been widely used in conjunction with other separation techniques due to its sensitivity and selectivity by the application of tandem mass spectrometry. This review provides an overall and critical picture of the current methodologies used for the analysis of PS in foods, particularly focused on the individual applications and limitations.

Automated summary

Plant sterols are bioactive compounds found in all vegetable foods, with potential beneficial effects on lowering cholesterol levels. Analytical methods are needed to assess their health benefits and future applications. Current methodologies include extraction and analysis, with mass spectrometry widely used for its sensitivity and selectivity.