Plant Hydrosols
Plant hydrosols, also known as the ‘mild sisters’ of essential oils, are highly effective yet often overlooked in favor of their more concentrated counterparts. They are particularly suitable for sensitive and older individuals, pregnant women, and children due to their gentle nature. But what exactly are plant hydrosols?
Plant Hydrosols: Natural Co-Products with a Wide Range of Effects
Hydrosols, or floral waters, are produced by steam distillation during the extraction of essential oils. During this process, water vapor moves through the plant material, cools down, and reverts to liquid form. The resulting aqueous solution, known as a hydrosol, contains the water-soluble ingredients of the plant, while the essential oil, which contains the volatile and fat-soluble ingredients, floats on the surface and can be skimmed off. For instance, lavender essential oil is known for its calming and disinfecting effects, and lavender hydrosol shares these properties, albeit in a milder form.
Historically, plant hydrosols were used by ancient civilizations such as the Romans, Egyptians, and Greeks. These distilled plant materials are rich in valuable ingredients and possess intense fragrances. However, ensuring high quality is crucial to prevent contamination, as hydrosols, being aqueous solutions, are more susceptible to germs compared to essential oils. Therefore, plant hydrosols should be stored in a dark, cool place. Products containing plant hydrosols are often packaged with a spray head to minimize oxygen exposure. A milky-cloudy appearance in a hydrosol does not indicate spoilage; rather, it signifies a higher concentration of active ingredients.
To extend the shelf life of pure plant hydrosols, ethanol can be added, preferably from sustainable organic alcohol production. It is advisable to avoid other additives and maintain high standards in the production and storage of plant hydrosols.
Plant hydrosols in cosmetics
Plant hydrosols provide the skin with the effect that the respective plant can also offer. Their areas of application include bath additives, facial tonics, refreshing sprays, room fresheners and aromatherapeutic applications. They can be used pure or integrated into cosmetic formulations. They are also suitable as cooling compresses for sunburn, inflammation, minor wounds and sports injuries.
Plant hydrosols can also be used as a complete water substitute, which significantly increases their natural cosmetic character and enhances their beneficial effect. Plant waters are often also available as upcycling substances and are therefore used in food production, for example. The advantage of the effect, including sustainability, can be effectively marketed with plant hydrolates.
Some of the best-known and most effective Plant hydrosols are presented below:
Neroli hydrolate
INCI: Citrus Aurantium Amara Flower Water
CAS number: 8016-38-4
EINECS number: 277-143-2
Alternative name: Orange blossom hydrolate
Description: a clear, colourless liquid
Possible uses: for facial toners, after-sun products, as a water phase in creams for mature skin and as a base for after-shaves
Main ingredients: linalool, alpha-terpineol, cis-phytol
Neroli hydrolate is a delicately scented floral water obtained from the distillation of white bitter orange blossoms. It has a germicidal effect and is therefore often used to treat skin irritations, acne and inflamed skin. As neroli plant hydrolates also have a decongestant, cooling and soothing effect, they are particularly suitable for use as a compress or facial toner. Neroli hydrolate is also known to support the skin’s regeneration process.
Rose hydrolate
INCI: Rosa Damascena Flower Water
CAS number: 90106-38-0
Possible uses: as facial toner, body spray, for emulsions and creams, as mouthwash for fresh breath
Main ingredients: vitamin B, vitamin C, pectins, tannins
Pure rose hydrolate is suitable for all skin types. It neutralises the pH value (good for sensitive skin), has an antibacterial and anti-inflammatory effect (ideal for blemished skin), provides dry skin with sufficient moisture and mattifies oily skin. Mature skin also benefits from rose water, as it prevents free radicals and can plump up wrinkles. Anyone suffering from rosacea will appreciate the toning and astringent effect of rose plant hydrolates. The scent of rose water has a relaxing effect and helps with inner restlessness. Sitz baths relieve discomfort after an episiotomy and in the case of haemorrhoids.
Peppermint hydrolate
INCI: Mentha Piperita (Peppermint) Leaf Water
CAS number: 84082-70-2
EINECS number: 282-015-4
Possible uses: as a body and face spray, shaving lotion and facial toner as well as after-sun care
Peppermint water has a clarifying and cooling effect. It cares for blemished skin, refreshes tired and heavy legs and can even relieve mild headaches. On hot days or after sunbathing, it provides a soothing freshness boost. Peppermint plant hydrosols can also promote concentration in stressful situations or when driving, for example.
Rosemary hydrolate
INCI: Rosmarinus Officinalis (Rosemary) Floral Water
CAS number: 84604-14-8
EINECS number: 283-291-9
Applications: as facial toner especially for oily skin, for hair care products
Rosemary hydrolate plays an important role in aromatherapy as it has a revitalising and stimulating effect. In cosmetics, it is particularly suitable for the care of oily and blemished skin and for high-quality shower gels. However, it can also be used in hair care as it stimulates the scalp and is even said to counteract hair loss. Oily hair is gently and thoroughly cared for with rosemary hydrolate.
You can find more information about rosemary in our article Rosemary extract.
Birch hydrolate
INCI: Betula Alba Leaf Water
CAS number: 84012-15-7
Most important ingredients: flavonoids, potassium, tannins and bitter substances, resin, saponins
Possible uses: for skin and hair care
Birch hydrolate is rich in electrolytes, glucose and plant acids. For this reason, athletes like to use it as an isotonic drink. It also has antibacterial, antiviral, antimicrobial and anti-inflammatory properties. Scalp massages with birch hydrosol can help against hair loss, dandruff and eczema. Impure skin becomes cleaner and clearer with regular use of facial toner with birch hydrosol. Dry and barrier-damaged skin, on the other hand, benefits from the protective and moisturising properties. Birch hydrosol also has a collagen-stimulating and slightly brightening effect.
Cucumber hydrolate
INCI: Cucumis Sativus Fruit Water
CAS number: 89998-01-6
Possible uses: soothes and hydrates the skin.
Cucumber hydrolate has an antioxidant effect and clarifies the skin. It tightens the pores and refreshes. When used regularly with a suitable toner, the skin looks smoother and firmer. The ingredients also have a decongestant effect, which means that cucumber hydrosol is particularly helpful for a swollen eye area.
You can find more information about cucumber in our article.
Sandalwood hydrosol
INCI:Santalum Album Wood Extract
CAS number: 84787-70-2
Possible uses: clarifies the skin and promotes an even complexion.
Sandalwood hydrosol has a very warm and sensual fragrance. It has a cell-renewing and slightly sweat-reducing effect and is very suitable for anti-ageing products. Sandalwood hydrosol is also ideal for the care of blemished and oily skin. Rubbing with sandalwood hydrosol provides relief from muscle tension.
Disadvantages of Plant Hydrosols
While plant hydrosols offer numerous benefits in cosmetics, there are also some potential drawbacks to consider:
- Quality Variations: The quality of plant hydrosols can vary significantly based on the manufacturing process, the quality of raw materials, and storage conditions. These factors can influence the consistency and effectiveness of the hydrosol.
- Allergenic Potential: Although generally gentler than essential oils, plant hydrosols can still contain allergens that may trigger reactions in sensitive skin.
- Fragrance Longevity: The fragrance of plant hydrosols tends to evaporate more quickly compared to conventional perfumes or fragrance oils. As a result, the scent in cosmetic products may not be as long-lasting, which could affect the desired fragrance profile.
Plant Hydrosols in Sophisticated Cosmetics from Cosmacon
Thanks to their low fat content and natural ingredients, plant hydrosols can be utilized in a variety of cosmetic applications. Their uses and effects are generally aligned with those of the original plant, making them versatile components in formulations such as cleansing tonics, aftershaves, and body sprays. If you are interested in the numerous benefits of different plant hydrosols, we are happy to provide advice and support in developing high-quality cosmetic formulations with plant hydrosols upon request.
Sources:
Plant hydrolates – Antioxidant properties, chemical composition and potential applications.; Biomed Pharmacother. 2021 Oct;142:112033.
Amended Safety Assessment of Mentha piperita (Peppermint)-Derived Ingredients as Used in Cosmetics.; Int J Toxicol. 2023 Dec;42(3_suppl):117S-143S.
Chemical analysis, antioxidant and antimicrobial activity of three Greek cucumber (Cucumis sativus) cultivars.; Georgios Sotiroudis, Eleni Melliou, Theodore G. Sotiroudis and Loanna Chinou.Journal of Food Biochemistry, 34 (2010) 61–78.