The effect of ultrasound pretreatment on some selected physicochemical properties of black cumin (Nigella Sativa)

• Autor(a) principal: Moghimi, Masoumeh
• Data de Publicação: 2018
• Outros Autores: Farzaneh, Vahid, Bakhshabadi, Hamid
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.1/10781
• topic: Ultrasound pretreatment; Physicochemical properties; Black cumin; Total phenols

Background In the present study, the effects of ultrasound pretreatment parameters including irradiation time and power on the quantity of the extracted phenolic compounds quantity as well as on some selected physicochemical properties of the extracted oils including oil extraction efficiency, acidity and peroxide values, color, and refractive index of the extracted oil of black cumin seeds with the use of cold press have been studied. Methods For each parameter, three different levels (30, 60, and 90 W) for the ultrasound power and (30, 45, and 60 min) and for the ultrasound irradiation time were studied. Each experiment was performed in three replications. Results The achieved results revealed that, with enhancements in the applied ultrasound power, the oil extraction efficiency, acidity value, total phenolic content, peroxide value, and color parameters increased significantly (P < 0.01). Enhancements in ultrasound irradiation time have not significantly increased the oil extraction efficiency, acidity value, total phenolic content, and peroxide value as well as the oil refractive index (P < 0.05). As the highest oil extraction efficiency (39.93%) was obtained from the seeds when the applied ultrasound power and time were 90 W and 60 min respectively, and the lowest acidity value of oil was achieved once the applied power and time of ultrasound were 30 W and 30 min respectively. The application of ultrasound as pretreatment has not shown any significant effects on the refractive index of the extracted oils (P > 0.05). Conclusions In summary, it could be mentioned that the application of ultrasound pretreatment in the oil extraction might improve the oil extraction efficiency, the extracted oil’s quality, and the extracted phenolic compounds content.