Isoflavone-rich extracts from okara using supercritical fluid extraction: Kinetic modeling and characterization

The lipid fraction and bioactive compounds from okara, a by-product of soybean processing, have been extracted by supercritical fluid extraction. The effect of operating parameters, pressure (20–40 MPa), temperature (40–80 ºC), and cosolvent usage (0–10 %wt. ethanol), on the extraction kinetics has...

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Detalles Bibliográficos
Autores: Díaz de Cerio Alonso de Mezquía, Elixabet, Barea Gómez, Pedro, Melgosa Gómez, Rodrigo, Illera Gigante, Alba Ester, Sanz, María Teresa, Beltrán Calvo, Sagrario
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2024
País:España
Institución:Universidad de Burgos (UBU)
Repositorio:Repositorio Institucional de la Universidad de Burgos (RIUBU)
OAI Identifier:oai:riubu.ubu.es:10259/10205
Acceso en línea:http://hdl.handle.net/10259/10205
Access Level:acceso abierto
Palabra clave:Okara
Soybean by-product
Supercritical fluid extraction
Isoflavones
Tocopherols
Biotecnología alimentaria
Alimentos-Composición
Biotecnología
Food-Biotechnology
Food-Composition
Biotechnology
Descripción
Sumario:The lipid fraction and bioactive compounds from okara, a by-product of soybean processing, have been extracted by supercritical fluid extraction. The effect of operating parameters, pressure (20–40 MPa), temperature (40–80 ºC), and cosolvent usage (0–10 %wt. ethanol), on the extraction kinetics has been investigated, satisfactorily correlating the experimental data to the Sovov´ a’s model. Extraction yield by SFE ranged from 0.1014 g extract/g insoluble solid (IS) at 20 MPa and 80 ºC to 0.1081 g extract/g IS at 30 MPa and 60 ºC (from 9.2 to 9.8 g extract/100 g okara, respectively), similar to Soxhlet extraction with n-hexane (9.2 ± 0.2 g extract/100 g). Pressure positively affected the initial extraction rate, which also increased with temperature except for the lowest pressure of 20 MPa, exhibiting a typical cross-over behavior. The use of ethanol as cosolvent promoted the extraction of phenolic compounds and isoflavones, and was less important in the extraction of tocopherols. Extraction yield using ethanol increased up to 0.1100 g extract/g IS at 40 MPa and 40 ºC. As expected, the higher content of bioactive compounds in the sc-CO2 + ethanol extracts positively affected the antioxidant capacity, with the maximum found at 20 MPa, 40 ºC and 10 %wt. ethanol.