Assessment of the Nutritional Potential and Resistance to Oxidation of Sea Buckthorn and Rosehip Oils

Abstract

Cold-pressed oils from non-typical materials, such as wild rose and sea buckthorn, should meet certain requirements to be approved for consumption. The aim of this study was to evaluate the nutritional potential and selected quality parameters with particular emphasis on oxidative stability of two commercially available cold-pressed oils: rose hip oil and sea buckthorn oil. The fatty acid composition, including nutritional indexes (polyunsaturated fatty acid/saturated fatty acid ratio PUFA/SFA; atherogenicity index IA is as follows: hypocholesterolemic/hypercholesterolemic index HH; health-promoting index HPI), positional distribution of fatty acids, melting profile and oxidative stability were analyzed. The tested oils were characterized by a high content of unsaturated fatty acids, which were mainly represented by oleic and linoleic acids. In the case of one of the analyzed rosehip oil oils (R1), α-linolenic acid was also found at the level of 26%, which contributed to obtaining the recommended ratio of omega-6 to omega-3 fatty acids. The lowest value of IA and the highest values of HH and HPI were also recorded for R1 rosehip oil. This oil was also characterized by the highest resistance to oxidation, as indicated by induction times measured at various temperatures. The distribution of fatty acids in triacylglycerols molecules in the analyzed oils was typical for vegetable oils. In the case of tested oils, similar melting profiles with endothermic peaks recorded at negative temperatures, which resulted from the presence of triacylglycerol fractions with a high proportion of mono- and polyunsaturated fatty acids, were observed.