Preliminary study of the influence of CO2 extraction conditions on the ester, aldehyde, ketone and hydrocarbon content of grape bagasses from jam production

Abstract

The main objective of this work was to assess the influence of temperature and pressure on the chemical characteristics of the essential oil obtained from CO2 extraction of grape bagasses in the production of jam. The experiments were performed in a laboratory-scale unit, where the effect of temperature (290 and 303 K) and pressure (15 and 25 Mpa) was investigated in terms of liquid yield and chemical composition of the extracts. The CO 2 mass flow rate was kept within a range of 2.5 to 3.0 g/min. The instrumental analysis was performed by gas chromatography with a mass spectrometer detector (GC-MS). The extraction conditions investigated in this work had no significant influence on the mass of essencial oil extracted. The main compounds identified in the extracts by the GC-MS spectra library (match quality higher tan 90%) were octadecane, dihydroxy ergostene-dione and phenylethyl n-decanoate when the temperature was increased from 290 to 303 K. Heptanal, ethyl ester of decosonoic acid and hexatriacontane were the individual compounds with the greatest increase in the chromatographic peak area when the pressure was increased from 15 to 25 Mpa. The most important class of compounds were hydrocarbons at 303 K and 15 MPa and were ketones and aldehydes at 25 Mpa and 290 K.