Extraction of Oil from Oilseeds using Supercritical Fluid

Significance of Supercritical Fluid Extraction in Oilseed Analysis

Supercritical carbon dioxide extraction provides a solvent free approach for oil quantitation in seeds. Elimination of organic solvents reduces environmental and safety concerns while delivering extraction conditions that mimic industrial processes.

Objectives and Study Overview

The study aims to evaluate the accuracy, precision and speed of supercritical CO2 extraction relative to standard soxhlet solvent extraction for various oilseeds. Two extraction protocols are compared: one to match industrial solvent recoverable oil and the other to achieve exhaustive total oil recovery.

Used Instrumentation

• Spe-ed SFE Supercritical Extraction System from Applied Separations
• Modifier pump for co solvent addition
• Spe-ed Matrix packing material
• Spe-ed Wool sample containment
• Industrial grade carbon dioxide supply

Methodology

• Weigh 2 g of ground oilseeds with 0.1 mg accuracy
• Load sample into a 24 mL extraction vessel with Spe-ed Wool and packing matrix
• Seal vessel and install in the SFE system
• Apply extraction conditions at 7500 psi and 100 °C
• Protocol one uses a CO2 flow of 6 L/min; protocol two uses 3 L/min CO2 and 0.9 mL/min ethanol modifier
• Collect extract in preweighed vials containing Spe-ed Wool and dry to constant weight
• Perform each extraction for 30 minutes dynamic time

Main Results and Discussion

Oil yields by SFE matched soxhlet extraction within one percentage point for soyflakes, canola and wet milled corn germ. Relative standard deviations remained below two percent, indicating comparable precision. Extraction time was reduced from several hours to thirty minutes, improving sample throughput. The absence of organic solvents enhanced laboratory safety and simplified waste handling.

Benefits and Practical Applications

• Elimination of hazardous solvents and improved safety
• Faster extraction supporting high throughput analysis
• Adjustable parameters for diverse seed matrices
• Relevance to industrial oilseed processing conditions

Future Trends and Potential Applications

• Coupling SFE with mass spectrometry for detailed compound profiling
• Automation and inline monitoring for process control
• Scale up for pilot and production scale extraction
• Exploration of alternative supercritical solvents and green cosolvents

Conclusion

Supercritical CO2 extraction offers an ecofriendly and reliable alternative to conventional solvent based methods for oilseed analysis. It achieves comparable accuracy and precision while shortening analysis time and eliminating hazardous waste.

Reference

• Taylor CA King JW Journal of the American Oil Chemists Society Vol 70 No 4 April 1993
• AOCS Official Method AM 3-96 Oil in Oilseeds Supercritical Fluid Extraction Method