Estratégias de utilização da noz pecã [Carya illinoinensis (Wangenh) C. Koch]: obtenção de óleo por fluidos pressurizados e aplicação de extratos bioativos em filme biodegradável

Abstract

This work aimed to evaluate the processes of obtaining pecan oil and pecan pie by pressurized fluids (carbon dioxide - CO2 and liquefied petroleum gas - LPG), as well as to elaborate bioactive extracts of pecan nut cake (PNC) and apply them to biodegradable and edible films. To obtain the oils, a planning 22 was prepared with a triplicate at the central point, varying the pressure and temperature conditions. For extraction with pressurized CO2, a pressure of 150-250 bar and a temperature of 20-60 °C were used; for the extraction with pressurized LPG, a pressure of 10-25 bar and a temperature of 20-40 °C were used. The study of pecan oil extraction sought to evaluate the extraction yield, antioxidant activity, fatty acid profile, bioactive compounds (squalene and β-sitosterol), and the chemical quality parameters of the oils. The highest yields were observed at 250 bar / 20 °C and 10 bar / 20 °C for CO2 and LPG extractions, respectively. All oils showed DPPH radical inhibition above 70%. Oleic acid was the predominant fatty acid in all samples. The highest values of bioactive compounds (squalene and β-sitosterol) were found in oils extracted with CO2. PNC oil was characterized in terms of extraction yield, fatty acid profile, lipid quality, squalene and β-sitosterol content and physical-chemical quality. The highest yields were obtained at 250 bar / 20 °C (CO2) and 10 bar / 20 °C (C-LPG). The chemical profile of oils is mainly characterized by fatty acids, where oleic and linoleic acids were the major compounds found in all samples. Squalene and β-sitosterol contents were also obtained in the oils. The results showed that PNC is an interesting biomass for oil extraction and whose separation processes using compressed fluids are an attractive option to process it. To obtain the extracts, a planning 22 with triplicate was used at the central point where the influence of the extraction parameters, such as ethanol alcohol content (%) and extraction time (min) on the content of phenolic compounds, was evaluated. The condition that presented the highest content of total phenolic compounds (101.61 mg GAE / g) was the one that used the lowest alcohol concentration and the shortest extraction time (condition 1 - 65% alcohol / 20 min), being the condition chosen to be incorporated into the films. The addition of 10 and 20% TNP extract to the films showed an increase in the elongation of the break, causing an increase in the opacity and darkening of the films. The incorporation of the PNC extract in the films significantly increased the antioxidant activity.