Chemical characterization of gurguéia nut (Dipteryx lacunifera Ducke) and press cake oil obtained by hydraulic pressing and supercritical extraction
Gabriela Polmann, Gerson Lopes Teixeira, Pedro Henrique Santos, Gerardo Álvarez Rivera, Elena Ibañez, Alejandro Cifuentes, Sandra Regina Salvador Ferreira, Jane Mara Block
March 2023
https://doi.org/10.1007/s13399-023-04042-x
Abstract
Dipteryx lacunifera, known as gurguéia nut, is a potential crop for obtaining specialty oils. The processing of gurguéia nut to obtain the oil generates circa 635 g kg−1 of cake, a biomass rich in residual oil. A sequential approach using hydraulic pressing (HP) and supercritical fluid extraction with CO2 (SFE-CO2) has been employed to maximize the oil recovery from gurguéia nut. High contents of β-sitosterol (55.8 mg 100 g−1), stigmasterol (38.6 mg 100 g−1), campesterol (13.9 mg 100 g−1), squalene (668.7 mg 100 g−1), total phenolics (6.1 mg GAE 100 g−1) and antioxidant potential (4.2 mg TE 100 g−1 in FRAP; 5.4% in DPPH; and 54.3% in ILP) were observed in the oil from SFE-CO2 as compared to HP and Soxhlet oils. Significant contents of γ- and α-tocopherol (3.5–4.2, and 18.2–21.5 µg g–1) were found in oils. Oleic (~ 60%), palmitic (9.9–18.9%), and linoleic (11.6–12.9%) were the major fatty acids. As a result, the main triacylglycerols were OOO (23.0–35.5 wt%), POO (13.4–31.3 wt%), and OLO (2.1–15.6 wt%). Thermal analysis revealed two major exothermic events during crystallization and a single peak on melting, also showing that gurguéia oils are liquid at 20 °C. Combining sustainable technologies was useful for valorizing residual biomass from hydraulic pressing to obtaining a high-quality oil with potential uses in the food, cosmetic and pharmaceutical industries.
