Ⅰ.Introduction to Supercritical CO2 and RSM
Supercritical CO2 extraction technology is a green and environmentally friendly extraction method that has been widely used in the fields of food, medicine and the chemical industry. White soursop oil, a natural oil that is rich in unsaturated fatty acids and a variety of bioactive components, possesses high nutritional and medicinal values. However, the conventional extraction process for white soursop oil is characterised by several drawbacks, including low efficiency, significant energy consumption and substantial pollution. Consequently, there is a significant need to study an efficient, green and environmentally friendly extraction process for white soursop oil.
Response Surface Methodology (RSM) is a methodology employed to optimise a multifactorial experimental design, whereby the optimal combination of process parameters can be predicted by mathematical modelling of the experimental results with a view to enhancing productivity and product quality. In this study, the response surface methodology was proposed for use in the optimisation of the supercritical C02 extraction process of white soursop oil. The objective of this study was to identify the optimal extraction conditions to enhance the extraction efficiency and quality of white soursop oil.
By optimising the process parameters of supercritical CO2 extraction of white foxglove oil, it is possible to enhance the extraction rate of white foxglove oil, reduce production costs and minimise environmental pollution. Furthermore, compositional analysis of the extracted oil can facilitate comprehension of its chemical composition and bioactive components, thereby providing a scientific foundation for the utilisation of white foxglove oil in the domains of food and medicine.
Ⅱ.Extraction Processes
Firstly, pretreatment of the white suet seed oil involves a series of processes, including filtration and decolourisation. The purpose of pretreatment is to remove impurities and pigments and improve the quality and stability of the oil. The resultant Bai Su seed oil was characterised by enhanced purity, a factor that was instrumental in facilitating the subsequent supercritical CO₂ extraction process.
Subsequently, extraction was carried out using supercritical CO₂ extraction technology. The specific operational procedure is as follows: the pretreated Bai Su seed oil is introduced into the high-pressure reactor, the appropriate temperature, pressure and residence time and other process parameters are set, and the supercritical CO₂ extraction is carried out. The employment of supercritical CO₂ extraction technology confers numerous advantages, chief among them being the capability to prevent the oxidation and escape of heat-sensitive components, thus ensuring the preservation of the active ingredients of Perilla frutescens seed oil. The technology is notable for its solvent residue-free operation, which ensures safety and environmental friendliness, while exhibiting a high level of extraction efficiency.
Following the completion of the extraction process, the extract is subjected to rotary evaporation, a process which results in the collection of the extracted Bai Su seed oil. The rotary evaporation process serves to remove the supercritical CO₂ that was utilised during the extraction process, thereby yielding pure Shirasu seed oil.
Finally, the extracted Perilla frutescens seed oil was analysed by gas chromatography-mass spectrometry (GC-MS), a technique that can accurately analyse the chemical composition of Perilla frutescens seed oil and provide a scientific basis for product quality control and application development.
Ⅲ.Conclusion
The findings of the response surface methodology optimisation study indicated that the pivotal factors influencing the supercritical CO2 extraction of S. alba oil were the extraction temperature, pressure, and residence time. The optimum extraction conditions were determined by the response surface method, with the temperature set at 45 ℃, the pressure at 30 MPa and the residence time at 40 min. White soursop oil has been found to be rich in unsaturated fatty acids, such as linoleic acid, oleic acid and linolenic acid, as well as vitamin E, phytol and other bioactive components. Notably, the content of linoleic acid and oleic acid accounts for more than 80% of the total fatty acids, signifying that white soursop oil possesses high nutritional value.
In comparison with conventional extraction methodologies, supercritical CO2 extraction of white foxglove oil exhibits significant advantages. Firstly, there is no solvent residue in the extraction process, which is conducive to ensuring the purity and safety of the product. Secondly, the method is green and environmentally friendly, which meets the requirements of modern industrial production. Finally, through the optimisation of the process parameters, the extraction rate and the quality of white soursop oil can be improved.
