Comprehensive gas chromatography with mass spectrometry analysis of sterols in red goji berries (Lycium sp.)

[Display omitted] •25 sterols were detected in fresh red goji berries (L. barbarum and L. chinense).•The rare campesta-5,24(25)-dienol was abundant in all red goji berry samples.•Examination of changes in the sterol pattern during the drying of red goji berries.•A new method of merging GC/MS chromatograms of separated seeds and flesh.•Food authentication of red goji berry samples possible based on sterol patterns. Gas chromatography with mass spectrometry (GC/MS) and fractionation steps were used to determine the sterol patterns of red goji berries in detail. Twenty-five sterols were detected in fresh berries of two species (Lycium barbarum and L. chinense) from bushes grown in the botanical garden of the University of Hohenheim, and 20 sterols were identified. The rarely occurring campesta-5,24(25)-dienol, β-sitosterol, Δ5-avenasterol, campesterol, and cycloartenol represented >60 % of the total sterol content. Maturity and drying of fresh red goji berries caused small changes but did not affect the characteristic sterol pattern. This was confirmed by analyzing various commercial dried red goji berry samples from different sources. Separated flesh and seed samples revealed pronounced differences in the sterol pattern. A new method of merging GC/MS chromatograms showed that ∼75 % of the sterols were present in seeds and ∼25 % in flesh. The unique sterol profile may be exploited to authenticate red goji berries.