The Oenocarpus distichus species is a native palm from Brazilian Amazon biomes, popularly known as bacaba-de-leque. Its economic value is mainly based on the palm heart exploitation and the fruits pulp oil extraction, used for edible purposes. Despite this, there is little knowledge about this species, especially regarding its functional characteristics and its nutritional contribution to local populations and society in general. Therefore, in this thesis, three research manuscripts were produced in order to promote the valorization of the species in the industrial scenario. The studies were carried out by applying supercritical carbon dioxide (Sc-CO2) for the extraction of oil from the lyophilized bacaba-de-leque pulp under different process conditions. In the first article, the operating temperatures of 50 °C was applied, combined with pressures of 150, 220 and 350 bar, and 60 °C, combined with pressures of 190, 270 and 420 bar, to obtain the best oil yield. Its chemical composition was evaluated, as well as the bioactive compounds contents present in the pulp before and after extraction. The maximum oil yields were reached at 50 ºC/350 bar (45.23%) and 60 ºC/270
bar (45.90%). The oleic, palmitic, and linoleic acids, as well as the predicted triglycerides OLiO, PLiO, OOO, POP, and POO were predominant in the oil composition, independent of the extraction conditions, and presented excellent functional quality. There was an increase in phenolic compounds, total anthocyanins contents, and antioxidant capacity of the bacaba-deleque pulp extracts after the Sc-CO2 extraction. In the second article, the nutritional and physicochemical properties of the oil extracted by Sc-CO2 at 50 °C/350 bar were investigated, as well as its thermal stability, the presence of functional compounds and the cytotoxic effect. The extracted oil showed 21.36 μg/g oil of total carotenoids. The quality parameters evaluated, which define the physicochemical properties, presented values within the standards recommended by the legislation for crude vegetable oils, and were similar to those of edible oils marketed in Brazil and in other countries. The thermogravimetric profiles indicated relative thermal stability at 210 ºC. The spectral bands, determined by FTIR, showed that the extraction method and the operating conditions applied did not alter the characteristic functional group profile. The cytotoxicity tests revealed that the extracted oil had no cytotoxic effect. The third article consists of a study of the supercritical extraction kinetics of bacabade- leque oil in two extraction vessels (V1 and V2) at different solvent flows (𝑄𝐶𝑂2) at 50 °C/350 bar and 60 °C/270 bar. The experimental data were properly adjusted by modifying the Broken-and-Intact Cell (BIC) model, proposed in the literature. Lastly, experimental and predicted scale-up procedures were evaluated, correlating operational variables in different bed geometries. The operational parameters applied did not influence the final oil yields. However, the initial stages of extraction were visibly affected. The use of the correlation between bed height and diameter (Hb/Db) and 𝑄𝐶𝑂2 , for the same feed mass (F), was not enough to reproduce the experimental kinetic curves from V1 (5×10-5 m3) to V2 (10-4 m3). However, when expressed as a function of solvent consumption, the curves converged to the same line, showing that the total amount of CO2 consumed was responsible for the process efficiency. In predicting scale-up, the increase of F and 𝑄𝐶𝑂2 for the same Hb/Db proved to be adequate to reproduce the kinetic behavior of the experimental scale in larger scales. The results of these studies showed that bacaba-de-leque oil is presented as a high-quality product, which is attributed to its chemical composition and functional properties, and provide information that allows the improvement and technical feasibility of oil extraction for possible application on a commercial scale.
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