The use of essential oils has become "essential" for modern living. Essential oils can be primary ingredients in perfumes for cosmetics or soaps and detergents. They form the basis of the spices in our foods.
So then why the interest in using supercritical fluids (i.e. CO2)?
As with natural products, SCF CO2 extracts the essential oils more efficiently than petroleum based solvents, but, maybe more important upon returning to an ambient state, the CO2 becomes a gas, leaving no residue. The flavor or fragrance is in its unadulterated state. There is no solvent taste or smell.
With temperatures less than body temperature (37°C), little thermal degradation of sensitive compounds occurs. Steam distillation is used in many current procedures, but with this exposure to temperatures over 100°C destroy, many of the “top notes” are destroyed or are swept away, severely reducing their yield.
Load the feedstock into an extraction vessel only once and then by only changing pressure of the SCF CO2, you can make it have the solubility characteristics of a myriad of different petroleum based solvents. You don’t need to add or change solvents.