Valorization of Camelina Cake by Fractionation: Characterization of Nutritional and Functional Properties

The objective of this study was to investigate the effects of fractionation by sieving on cold-pressed camelina cake by separating it into particle-sized fractions and evaluating their nutritional and functional properties. Two Camelina sativa varieties, NS Zlatka and NS Slatka, were mechanically cold-pressed using a screw press then ground into flour. The resulting material was fractionated into three particle-sized fractions, >250 µm, 250-180 µm, and <180 µm, using a laboratory dry sieving system. Both the whole cake and the separated fractions were analyzed for proximate composition, amino acid and fatty acid profiles, tocopherol content, antioxidant potential, color characteristics, and water and oil absorption capacities. The results indicated that the finest cake fraction (<180 µm) from both camelina varieties contained the highest content of protein (~40%), fat (17-19%), essential amino acids (~17 g/100 g), γ-tocopherols (254-266 mg/kg), and the lowest content of condensed tannins (0.5-0.9 g/kg). It also displayed a lighter color and increased yellowness. However, it contained the highest concentrations of glucosinolates (24-27 μmol/g) and phytic acid (38-41 g/kg). In contrast, the coarsest fraction (>250 µm) had increased crude fiber content (13-15%), higher antioxidant potential, the greatest water absorption capacity, and a darker color with a more pronounced reddish color. It also contained the lowest levels of glucosinolates (19-21 μmol/g) and phytic acid (17-20 g/kg). In conclusion, whole camelina cake and its fractions demonstrate considerable potential for use in animal feed and a variety of human nutritional products, due to their favorable nutritional composition and functional properties. Fine fractions with high levels of antinutritional compounds could be used as a substrate for the extraction of bioactive compounds and may find further application in the cosmetic and pharmaceutical industries.