Fat and fat-soluble biologically active compounds in the processing residue of sea buckthorn fruit

The valorization of secondary raw materials allows us to reduce negative environmental impact while maximizing the raw material's phytochemical potential. Sea buckthorn berries consist of pulp and seeds. The pulp is mainly used in juice production, leaving behind the fruit skin and seeds. Our study aimed to investigate the chemical composition of the residue using the GC method and select the optimal method for extracting fat and fat-soluble compounds. The GC analysis of the obtained fat mainly identified C16 and C18 fatty acids. SFE (using carbon dioxide) allows the extraction of fat and carotenoid preparation (working regime: pressure 350 bar at 50°C, carbon dioxide supply rate 20 g/min). US extraction used a "green" solvent—ethanol of different concentrations (50%, 75%, and 96% ethanol). The relatively higher fat yield of 20% was recorded with 96% ethanol extraction. The optimal conditions for fat extraction were selected as a solid-mass-to-solvent ratio of 1/30 for dried samples, temperature of 30°C, amplitude of 90%, frequency of 40KHz, power of 130W, working cycle - pulse, time - 20 minutes. The carotenoid content in the obtained fat was determined by the spectroscopic method and was 1.75 g/100 g based on dry mass. The physicochemical properties of the obtained fat were studied. The obtained preparations are characterized by high antioxidant activity.