Oleoresins are a blend of oil and spices that is naturally found in plants. They are endowed with a whole range of properties that provide umpteen health benefits. However, these positive health impacts are realized only when the correct process is used for oleoresin extraction. The supercritical fluid extraction (SCFE) process is suitable for oleoresin oil extraction because it extracts the oleoresin molecules in their largely pure form.
Speaking of the desired properties of oleoresins, these include:
Due to these properties, oleoresins are useful against multiple health conditions such as:
- Mitigating Risk of Diarrhea and Cancer
- Colic Flatulence
- Digestion Issues
- Urinary Infections
- Muscle and Joint Ache
Factors promoting the use of oleoresins are as follows:
- Availability of oleoresins in a concentrated form, something that simplifies their storage and transport.
- Rising cognizance of the health benefits of natural extracts vis-a-vis their synthetic counterparts.
- Growing consumption of health supplements.
All these drivers have teamed up and will propel the worldwide oleoresin market to a healthy $1.9 billion in 2025 after registering an impressive 6% CAGR from 2019 onwards.
Paprika will continue to be the most popular source of oleoresins over the near future. Other sources of oleoresins include:
- Cinnamon & Cassia
- Seed Spices
Two main methods utilized for oleoresin extraction are:
- Supercritical Fluid Extraction (SCFE)
- Solvent Extraction
SCFE uses a supercritical fluid (SCF) – a fluid that is at a pressure and temperature that is more than its critical pressure and critical temperature respectively. When the pressure of the SCF changes, its solvent power i.e. ability to dissolve compounds from the raw material changes. By carefully controlling the pressure, its solvent power is fine tuned to extract just the required compound (also called target molecule). Other molecules in the raw material are not disturbed, or disturbed as little as possible.
What happens because of this is that the extraction action of the SCFE process becomes highly focused. If SCFE is used for oleoresin oil extraction, say for example paprika extraction, it will separate only the paprika molecule. Very little or zero part of other molecules will get added to the extract.
Carbon dioxide (CO2) supercritical fluid extraction (SCFE) uses supercritical CO2 (sCO2). Numerous desirable properties make CO2 the ideal supercritical fluid (SCF). CO2 has a:
- Critical temperature of 31.10C, which is around the ambient temperature.
- More manageable critical pressure of 73.9 bar.
- Non-flammable and non-toxic nature.
- Customizable density to upgrade its solvent power.
- Ample availability in pure form.
- Comparatively low cost.
The first feature is particularly important given the heat-sensitive nature of oleoresins. A low critical temperature, hovering around the room temperature, of CO2 means the CO2 SCFE process temperature is not very high. This makes it ideal for oleoresin extraction as also for oleoresin oil extraction because they do not get distorted on account of heat and high temperatures.
Other properties of CO2 enlisted above – namely its availability, non-toxic and non-inflammable nature, and relatively low critical pressure – improve other aspects of the SCFE process by cutting costs and making it more operationally manageable.