Integrated strategies for water removal and lipid extraction from coffee industry residues

Valorization of spent coffee grounds into biofuels and value-added products: Pathway towards integrated bio-refinery

“…Couto et al, [190] reported that utilization of ethanol as a co-solvent at ethanol:CO2 mass ratio of 6.5:93.5 (w/w), 20 MPa and 323 K achieved oil yield of 19.4% higher than without ethanol (13.1%) at the same pressure and temperature and higher than soxhlet extraction with n-hexane (18.3%). Mechanical extraction using hydraulic ram pressing and screw press has been reported in [192] and applying pressure with minimum quantities of solvents (ether or ethyl alcohol) that can be recycled back has been reported in [7]. This method has been developed at Università di Napoli Federico II, Italy.…”

Factors Affecting the Efficiency of Pressurized Solvent Extraction of Oil From Spent Coffee Grounds

“…Regarding the impact of ASE extraction temperature on the energy content of the obtained lipids, the HHVs of ICG oil samples extracted with hexane at temperatures of 125°C, 145°C and 165°C were found to be 38.53 MJ/ kg, 38.90 MJ/kg and 38.84 MJ/kg respectively, showing no systematic impact of extraction temperature on the oil energy density. It is also interesting to note that a previous study that examined the calorific value of SCG lipids obtained with hexane and ethanol through ASE found minor differences in their HHV, indicating that they contain similar amounts of carbon and hydrogen atoms, although this does not necessarily signify an equivalent lipid content (Efthymiopoulos, Hellier, Ladommatos, Kay, et al, 2018).…”

“…The fatty acid profile of ICG oil obtained through solvent extraction at atmospheric pressure conditions has been previously determined by gas chromatography, with linoleic (42% w/w), palmitic (32% w/w), oleic (10%w/w), stearic (8% w/w), eicosanoic (4% w/w) and linolenic acid (1% w/w) being the main fatty acids present (Efthymiopoulos et al, 2017). Previous studies have also shown that the unsaponifiable content of SCG oil extracted with hexane represented approximately 3% w/w to 5% w/w of total oil mass, based on transesterification yields achieved (Efthymiopoulos, Hellier, Ladommatos, Kay, and Mills-Lamptey, 2018;Kwon, Yi, and Jeon, 2013;Rocha et al, 2014).…”

Extraction and Characterization of Coffee Silverskin Oil With Potential Application for Enzymatic Synthesis of Fatty Acids

“…However, the oil extracted by soxhlet was shown to have a physical aspect (viscosity, coloring) more suitable for future applications. On the other hand, the oil obtained from ultrasound-assisted extraction was affected due to shear forces generated by the ultrasound cavitations, cell wall ruptures occurred, increasing the contact area between the solvent and the materials, intensifying the general oil extraction process and other compounds [12]. Considering the yields and quality of the extracted oil, the soxhlet extraction was ISSN: 2357-7592 selected as the most promising for the characterization of physicochemical properties and hydrolysis of the crude oil.…”