Vegetable glycerin is nowadays increasingly used as a humectant in cosmetic products. This means that glycerin is able to maintain a certain amount of water content where it is applied, basically it maintains moisture. Dry skin and hair need not worry! To be added to your cosmetic preparations, cream, milk, shower gel, shampoo, it presents a real protective interest.
Vegetable glycerin is generally presented in the form of a rather viscous and thick liquid, colorless and odorless. It is usually obtained by saponification of oils of ... vegetable origin, we would have guessed it from its name!
What is saponification?
Saponification is the chemical reaction to obtain soap. During this reaction, a fatty substance, associated with a strong base often soda, allows to obtain soap but also another product: the famous glycerin.
fatty acid triglycerides + soda → soap + glycerin
Glycerin can then be extracted and used for its many properties in cosmetics and domestic use.
Humidifying and moisturizing: Vegetable glycerin allows to attract and retain water thanks to its hygroscopic properties, it will thus help to maintain a perfect hydration at the cutaneous level. Obviously, it is necessary to respect the recommended dosages ;)
Skin protection: The moisturizing and humectant properties of vegetable glycerin help maintain a certain balance of the hydrolipidic film. The skin barrier will only be strengthened to protect the skin from external aggression.
Emollient: Vegetable glycerin is an excellent emollient, meaning that it softens and smoothes the skin but also the hair. It makes the treated areas more supple.
Lubricant: Glycerin is often used as an excipient in pharmaceutical products such as cough syrups or suppositories for example.
Solvent: Vegetable glycerin is very often used to facilitate the extraction of active plant ingredients in the preparation of hydroglycerinated macerates of plants for example. It also plays a role of preservative by absorbing water conducive to microbial development.
Stabilizer and thickener: In a cosmetic product, vegetable glycerin can promote a certain stability to your product, especially in the case of emulsions.
For use in cosmetics, vegetable glycerin must be added and dosed between 2 to 8% in an aqueous phase. Beyond this percentage, the humectant effect of glycerin is reversed. It attracts all the moisture it finds, even that present in the skin and hair and can then instead dry them out. Moreover, glycerin is of real interest if the ambient air is humid, it will capture the humidity and place it on the skin and hair for example. In the opposite case, if the ambient air is dry, glycerin risks to dry your skin or your hair by absorbing the water which it finds in the latter.
Namely, vegetable glycerin is suitable for all skin and hair types, especially fordry and dehydrated skin and hair. It is added in most aqueous cosmetic products. It should be mixed well so that it is dispersed throughout the preparation. Do not hesitate to perform skin tests on small areas, some skins may react badly.
In cosmetics, vegetable glycerin must be used diluted on the skin at the risk of causing irritation or mild allergies.
It is best to store your vegetable glycerin at room temperature and away from light, but especially away from moisture!
Obviously, in an ecological and responsible approach, we favor the use of glycerin of vegetable origin. However, as you know, glycerin can have various origins:
Note that you can find glycerin in many hygiene or cosmetic products. Be sure to check its origin. Whether it is of vegetable, animal or synthetic origin, it appears under the INCI name "Glycerin". However, if the glycerin is vegetable, the mention "vegetable" should be put forward ;)