Development of a Method for the Analysis of Sterols in Sterol-Enriched Deli-Style Turkey with GC-FID

Plant sterols have been recognised by the European Food Safety Authority for their cholesterol-lowering properties and are currently added to several food formulations. The objective of this study was to develop a method based on formation of sterol trimethylsilyl ether derivatives and separation and quantification by GC for the determination of three phytosterols (beta-sitosterol, stigmasterol and campesterol) in sterol-enriched deli-style turkey. The assay was linear (concentration range 4.3-172.1 mu g/ml, R (2) a parts per thousand yenaEuro parts per thousand 0.9868) and accuracy and precision were within the acceptance criteria of the U.S. Food and Drug Administration (USFDA) guidelines for method validation, set at < 20 % RSD at the lower limit of quantification (LLOQ) and < 15 % RSD for all other standards. Accuracy measured by relative response factor (RRF) also met the USFDA validation criteria. No matrix effects were observed. The response factors (RFs) of the three sterols differed significantly to that of the internal standard (ISTD) used, leading to RRF dissimilar to 1 (campesterol = 1.0167, stigmasterol = 1.4458, beta-sitosterol = 0.9029). This method is suitable for quantification in meat matrix, and it has been successfully applied to the determination of sterols in sterol-enriched deli-style turkey (21 mg sterols/0.5 g sample).