A validated gas chromatography-mass spectrometry (GC-MS) detection method for the quantitative analysis of sterol oxidation products (SOPs) in serum is described. After a lipid extraction procedure with chloroform/methanol, a cold saponification and purification by solid phase extraction, oxysterols were derivatizated to form trimethyl-sylil-ethers which were subjected to GC-MS analysis. Calibration curves for cholesterol oxidation products showed determination coefficient (R 2 ) of 1.0, with low values for the coefficient of variation of the response factors (<1%). Detection and quantification limits were below 5 ng/mL and 10 ng/mL, respectively. Recovery data were between 77.65 and 110.29% (CV<10% for all compounds).Good results were obtained for within and between day repeatability, with values below 10%. In conclusion, the method performed is suitable for the determination and quantification of SOPs in serum.2

An evaluation of the capacity of a lyophilized water extract of borage leaves to delay the lipid oxidation process in dry fermented sausages enriched with ω-3 PUFAs has been performed. Lyophilized extract (340ppm) showed an antioxidant capacity equivalent to 200ppm of a butylhydroxyanisol (BHA) and butylhydroxytoluene (BHT) mixture. Two batches of dry fermented sausages enriched in ω-3 PUFA were developed. One of them was supplemented with a synthetic antioxidants mixture (200ppm of BHA+BHT) and the other one with natural antioxidants (340ppm of lyophilized water extract of borage leaves). Furthermore, a traditional formulation of this type of dry fermented sausage (Control), was also manufactured. The natural extract gave rise to lower amount of volatile compounds (including hexanal), than the mixture of synthetic antioxidants (2202 and 2713ng dodecane/g dry matter, respectively). TBARS and Cholesterol Oxidation Products (COPs) did not show significant differences between products with different antioxidants. The sensorial analysis showed that lyophilized water extracts of borage leaves did not affect the sensorial properties of the products. From the economical and safety standpoints, the use of a by-product (borage leaves) and water as extracting solvent are valuable alternatives for obtaining natural antioxidants to be added to dry fermented sausages enriched in ω-3 PUFA.