Brief characteristics of oxidative stability, fatty acids and metal content in selected berry seed extracts obtained by the SFE technique and used as potential source of nutrients

•By carrying out the scCO2 extraction process of berry seeds, in selected parameters, oils rich in unsaturated fatty acids (UFA) with good n6/n3 fatty acid ratio were obtained.•Fractions collected during scCO2 extraction showed differences in FAs quantity composition and measured acid and peroxide values.•Changes in the area of several dozen units meq O2 per kg were shown for the peroxide values, confirming the ongoing oxidation processes.•By controlling the acid value as an indicator of the hydrolysis degree, in a given time unit, the shelf life of extract can be determined. Berry seeds are rich source of high quality oil containing valuable compounds such as polyunsaturated fatty acids and therefore, have been gaining increasing significance as potential source of nutrients for food, cosmetic or pharmaceutical industry. Supercritical carbon dioxide extraction of seeds was performed, for which oxidative stability analyzes and determinations of fatty acids, selected microelements and toxic metals were carried out. An attempt was made to evaluate unclassified scCO2 oil extracts from berry seeds, taking into account the lack of legislative documents specifying the required contents of metals and biologically active ingredients. The obtained extracts are products with the consistency of liquid oil. The total fatty acid content range from 59% to 98%, with unsaturated fatty acids predominating and very good n-3/n-6 fatty acids ratio. The analyzed samples were taken systematically from one extraction sequence also determining the acid and the peroxide values in subsequent fractions.