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The partitioning of predominant lipophilic olive bioactives (squalene, β‐sitosterol and α‐tocopherol) in olive oil processing was studied for the first time using common integrated olive milling plant. 7% of the oil and 5% of the squalene present in the olives was lost in the last pomace. β‐sitosterol and α‐tocopherol, which are mainly concentrated in the seed of the olive fruit, was recovered in virgin olive oil to a lesser extent (66%, 67%) while 10% were lost in last pomace. Thus, the loss of β‐sitosterol and α‐tocopherol was higher than that of squalene and oil, due to nonrecovered bound forms. 19% of the α‐tocopherol and 21% of the β‐sitosterol loss was unaccounted for, which can be attributed to degradation of α‐tocopherol and incomplete recovery of sterols from the olive and pomace matrices. This study provides a basis for process development studies.

Galanakis, Charis M./0000-0001-5194-0818; Secmeler, Ozge/0000-0002-5348-2782 WOS:000562474900009 Olive oil is one of the most reputative traditional foods in the world. Indeed, the cultivation of olives to produce olive oil has deep roots in the history of the Mediterranean region. Worldwide olive oil production was about 2.5 million tons in 2017, the majority of them (87% in 2017) in Mediterranean countries (IOC Production data, year 2016/2017). Spain, Italy, Greece, and Turkey (followed by Tunisia, Portugal, Morocco, and Algeria) are the biggest olive oil-producing countries, generating B1.3 and B0.2 million tons in 2017, respectively. Outside the Mediterranean basin, olives are cultivated in the Middle East, the United States, Argentina, and Australia.

45 Páginas.-- 3 Tablas.-- 2 Figuras, Hydrothermal pretreatments including steam explosion and subcritical water (SCW) facilitate hydrolyses of plant cell wall materials and supply environmentally friendly extraction solvents to recover value added compounds. In this study, effect of steam and SCW and temperature (160, 180 and 200 °C, 5 min) on yield and β-sitosterol content of pomace oil and phenolics were compared for value added utilization of olive pomace. Compared to acid hydrolysis, hydrothermal pretreatments yielded similar oil recovery. 54–76% of the bound oil and 18–32% of the bound β-sitosterol of the pomace were recovered by hydrothermal pretreatments. Steam pretreatment was more effective than SCW pretreatment at lower temperatures, however SCW showed increasing trend on oil yield related to steam pretreatment. As further research on process development, use of sequential temperature might be investigated, starting with steam explosion (200 °C) to obtain multiple, aqueous and meal, fractions for total valorization of olive pomace., This work was supported by the TUBITAK National Scholarship for PhD Students (2211c). Özge Seçmeler would like to thank Food Phytochemistry and Modifications of Lipids Departments of Instituto de la Grasa-CSIC for their help during her study.

The analytical methodologies utilizing HPLC or GC techniques for the determination of predominant lipophilic bioactives in olive oil (β-sitosterol, squalene, and α-tocopherol) may include a number of sample pre-treatment steps (such as clean up (using TLC and SPE), saponification, and derivatization) making them rather lengthy and impractical. The objective of this study was to develop a rapid and in-house validated GC-FID method for the simultaneous determination of these bioactives using response surface methodology for optimization of critical parameters (time and temperature of saponification and derivatization). In-house method validation based on method performance parameters (linearity, limit of detection (LOD), limit of quantification (LOQ), repeatability, and recovery) was carried out using optimized method parameters (10 min derivatization time for 30°C derivatization temperature, 56°C saponification temperature, and 10 min saponification time). The linear range of β-sitosterol, squalene, and α-tocopherol was determined to be between LOQ value (8.4; 16.0; 12.5 mg/100 g, respectively) and upper end (500; 700 mg/100 g for β-sitosterol; squalene, respectively) with acceptable accuracy, recovery (92–97%; 93–95%; 93–110%) and repeatability. Practical applications: The in-house GC-FID method developed in this study offers a rapid, accurate and validated method alternative to current official methods and simultaneous methods recently published in the literature. Time of analysis was reduced to ∼5 h for every six samples compared to ∼20 h specified in official methods. The developed method was fully validated covering all parameters; linearity, LOQ, LOD, recovery, and repeatability. This method can be incorporated into quality control programs for olive oil and its application areas can be expanded to include other plant oils after further validation studies. A new rapid multicomponent in-house validated method was developed to determine predominant lipophilics of olive oil.