A breakthrough study has unveiled optimized methods for extracting hemp seed oil, focusing on utilizing supercritical carbon dioxide (CO₂) combined with ethanol as a novel co-solvent. This research not only aims to boost oil yield but also enriches the oil's nutritional profile, making it more viable for health and industrial applications.
Hemp (Cannabis sativa L.) seeds are celebrated for their rich nutritional composition, comprising 25-35% lipids and 20-25% easily digestible proteins. These seeds are also abundant in unsaturated fatty acids, particularly polyunsaturated fats beneficial for cardiovascular health. The increasing demand for hemp products necessitates efficient extraction methods to maintain oil quality and safety standards.
The research employed response surface methodology (RSM) to optimize key extraction parameters: temperature, pressure, and ethanol proportion, aiming for the best yield of phenolic compounds alongside the oil. Findings indicated significant enhancements when using ethanol as co-solvent, particularly at 10% concentration, leading to oil yield surging to 30.13% and total phenolic content reaching 294.15 mg gallic acid equivalent (GAE) per kg.
Initially, supercritical fluid extraction (SFE) was tested using plain SC-CO₂. The researchers found optimal oil yield at 50°C and 20 MPa pressure over 244 minutes. These conditions resulted not only in reduced extraction time but also minimized the presence of undesirable components typically associated with other extraction methods.
"The best proportion was 10% ethanol, which significantly increased the oil yield to 30.13%, TPC to 294.15 GAE mg/kg, and total tocopherols to 484.38 mg/kg," the authors of the article reported, showcasing the method's efficiency.
Previously, conventional extraction methods like cold pressing and solvent-based approaches posed risks, including prolonged processing times and potential chemical residues. The introduction of supercritical CO₂ extraction delivers several advantages, such as eliminating harmful solvents and reducing the operational risk of oxidation during extraction, thereby preserving the structural integrity of the oil.
Phenolic compounds have garnered attention for their antioxidant properties. Effective extraction allows for higher concentrations of these compounds, contributing to the oil's stability and health benefits. The study’s results indicate the process not only retains the oil's nutritional profile but enhances it, laying groundwork for elevated health benefits and potential applications within the cosmetics and food industries.
This novel extraction process aligns with increased interest in sustainable production methods, avoiding harmful solvents, and addressing consumer demand for high-quality natural products. Utilizing ethanol as part of the extraction process has not only yielded more oil but also increased the oil's shelf life significantly—improving its oxidative stability index from 9.80 to 30.13 hours.
These advancements highlight the importance of optimizing extraction conditions to balance yield with the retention of bioactive compounds. By identifying optimal extraction conditions, the potential for hemp products expands even beyond culinary uses to functional food ingredients.
Further research is encouraged to explore the biological activities of the oil obtained through this method and to assess its applications across different sectors, including pharmaceuticals and skincare formulations. The insights garnered from this research promise to reshape how hemp seed oil is perceived and utilized, enhancing its position within the booming market for health-conscious consumers.
Overall, the findings denote significant progress toward sustainable and efficient methods for obtaining hemp seed oil, underscoring the quality, safety, and nutraceutical potential of hemp derivatives. The continued exploration of such methods will open new doors for hemp oil applications, aligning with modern consumer trends emphasizing health and wellness.