To extract oil from a plant, there are several methods. Each extraction method offers specific advantages, producing unique extracts suited to different parts of the plant such as the flower, the fruit seed, the leaf, and the root. A thorough understanding of these methods is essential to best preserve the biological properties of the plants. However, it is important to note that some processes can alter this biological richness, while others offer variable yields. Thus, a careful analysis of the extraction methods used in the cosmetic industry is crucial to ensure high-quality products while respecting the environment. Let’s explore together the different extraction methods throughout history, with their advantages and disadvantages.
Cold pressing: A millennial tradition preserving all the benefits
Cold pressing, practiced since ancient times by Mediterranean civilizations, is a gentle method that preserves the nutrients and aromas of vegetable oils. The ancient Egyptians and Greeks used rudimentary presses to extract olive oil, the precursor to this traditional technique. Below, we will see how cold pressing is done.
Solvent extraction: industrial revolution and mass production efficiency
Solvent extraction emerged during the industrial revolution, offering efficient mass production. This method uses chemicals, like hexane, to dissolve oils from seeds or fruits. However, it can alter the quality of the oils and pose environmental challenges.
Hot pressing: a blend of tradition and modernity
In the 20th century, hot pressing became popular, combining the advantages of cold pressing and solvent extraction. Although heat facilitates the extraction process, it can alter the nutrients and natural flavors of the oils.
Maceration: an ancient method reimagined
Maceration, an ancient technique of soaking plants in a liquid, has been reinvented to extract vegetable oils. This method uses a solvent, such as alcohol or oil, to extract the active compounds from the plants, preserving their properties.
Distillation: steam to extract essential oils and hydrosols
Distillation, a technique used for centuries to extract essential oils from aromatic plants, relies on the vaporization of volatile compounds. The process of extracting essential oils and hydrosols is the same, involving steam distillation. After condensation, where steam is cooled by a coil immersed in cold water, it transforms into liquid and is collected in an essence container or bottle. Through decantation, we obtain essential oil, which is composed of aromatic molecules that are hydrophobic (usually lighter than water), and hydrosol, which contains hydrophilic molecules along with a tiny amount of essential oil suspended in the water. The aromas and benefits of the essential oils are thus preserved.
At Roots, we only use organically sourced vegetable oils extracted through first cold pressing. Here’s why:
Cold extraction process of vegetable oils: details and benefits
Cold extraction of vegetable oils is a method that respects the nutrients and flavors, preserving the quality of oils while minimizing heat generated during the process. Here’s a detailed overview of the process and its benefits:
Preparation of raw materials
Before extraction, seeds, nuts, or fruits are carefully sorted and cleaned to remove impurities. They are then dried at low temperatures to reduce their moisture content, thus preserving the quality of the oils extracted.
Cold Pressing
The prepared raw materials are placed into a screw press or mechanical press. Under controlled pressure, the seeds are crushed to release the oil. Although friction between the seeds and the pressing surfaces can generate heat, this is kept at a low level through precise control of pressure and pressing speed. The goal is to maintain the temperature below 50°C (122°F) to avoid any deterioration of nutrients and flavors.
Oil Collection
The extracted oil is collected as it is released from the seeds. It then passes through a filter to remove solid particles and impurities, ensuring that the oil is clean and pure, ready for use.
Heat Control
In the cold pressing process, precise heat control is crucial to preserve the quality of the oils. Cold presses are designed to minimize the heat generated by adjusting the pressure and pressing speed. Additionally, modern machines are equipped with cooling devices to maintain a constant temperature and avoid excessive heat buildup.
Benefits of Cold Extraction
- Preservation of Nutrients: By avoiding excessive heat, cold extraction preserves the vitamins, antioxidants, and essential fatty acids naturally found in vegetable oils.
- Preserved Flavor and Aroma: The low temperature of the process helps retain the delicate flavors and aromas of the oils, offering superior taste quality.
- Quality and Versatility: Oils obtained through cold extraction are considered higher quality due to their gentle, unaltered process. They are ideal for cooking, skincare, and health products, offering versatility in use.
Cold extraction is a method that respects the nutrients and flavors, producing high-quality vegetable oils while preserving the benefits of seeds, nuts, or fruits.
