Herbal distillates, also known as floral waters, hydrosols, hydrolates, herbal waters, and essential waters, [1] are aqueous products of hydrodistillation. They are colloidal suspensions of essential oils as well as water-soluble components obtained by steam distillation or hydrodistillation (a variant of steam distillation) from plants and herbs. These herbal distillates have uses as flavorings and cosmetics. Common herbal distillates for skincare include rose water, [2] orange flower water, [3] and witch hazel. [4] Rosemary, [5] oregano, [6] and thyme [7] are hydrosols that may be used in food manufacturing industries.
Herbal distillates are produced in the same or similar manner as essential oils. However, essential oils will float to the top of the distillate where it can be removed, leaving behind the watery distillate. For this reason, the term essential water is an apt description. In the past, these essential waters were often considered a byproduct of distillation, but are now considered an important co-product. [8] The produced herbal waters are essentially diluted essential oils at less than 1% concentration (typically 0.02% to 0.05%). [9] Several factors, such as temperature and a herb's growth cycle, impact the characteristics of a distillate, and therefore influence the timing of the distillation. Rosemary, for example, should be distilled in the peak of summer before it flowers. [10]
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1. Food industry: Herbal distillates are often used in culinary applications to add subtle flavors to foods and beverages. Their mild nature makes them ideal for infusing delicate flavors into dishes without the overpowering intensity of essential oils. Commonly used distillates in this context include rose water, orange blossom water, and peppermint hydrosol. Herbal distillates are also used to preserve food, and have been shown to be effective in achieving desirable effects, like reducing the degree of oxidation of some meats. [11]
2. Cosmetics: In the cosmetic industry, herbal distillates are prized for their gentle, skin-friendly properties. They are used in a variety of products, including:
3. Herbal Treatments: Herbal distillates are also employed in traditional and holistic medicine for their therapeutic benefits. Due to their lower concentration compared to essential oils, they are often used for:
4. Agriculture: Herbal distillates are also used as insecticides, herbicides, and antibacterial and antifungal agents in agriculture. Additionally, herbal distillates may be used in allelopathy, with possible applications including the manipulation of the timing of sprouting (see vivipary) and germination. [11]
5. Clothing: Herbal distillates can be added to water in a clothes iron to add a delicate scent into clothing. Since herbal distillates do not contain hard minerals such as plastic and metal, [13] it will also help keep clothing irons working properly for much longer. [12]
The science of distillation is based on the fact that different substances evaporate at different temperatures. Unlike other extraction techniques based on solubility of a compound in either water or oil, distillation will separate components regardless of their solubility. The distillate will contain compounds that vaporize at or below the temperature of distillation. The actual chemical components of these orange herbal distillates have not yet been fully identified, but plant distillates will usually contain essential oil compounds as well as organic acids and other water-soluble plant components. Compounds with a higher vaporization point will remain behind and will include many of the water-soluble plant pigments and flavonoids. [14]
Because hydrosols are produced at high temperatures and are somewhat acidic, they tend to inhibit bacterial growth but not fungal growth. They are not sterile, and should be kept refrigerated to preserve freshness. [15] Herbal distillates degrade over time and will degrade faster than essential oils, which are more stable. [16] Small-scale producers of hydrosols must be particularly aware of the risk of bacterial contamination and take steps to prevent it. Despite concerns that there may be significant amounts of heavy metals in popular herbal distillates, this has not shown to be the case. [13]
Distillation, also classical distillation, is the process of separating the component substances of a liquid mixture of two or more chemically discrete substances; the separation process is realized by way of the selective boiling of the mixture and the condensation of the vapors in a still.
Rose water is a flavoured water made by steeping rose petals in water. It is the hydrosol portion of the distillate of rose petals, a by-product of the production of rose oil for use in perfume. Rose water is also used to flavour food, as a component in some cosmetic and medical preparations, and for religious purposes throughout Eurasia.
Perfume is a mixture of fragrant essential oils or aroma compounds (fragrances), fixatives and solvents, usually in liquid form, used to give the human body, animals, food, objects, and living-spaces an agreeable scent. Perfumes can be defined as substances that emit and diffuse a pleasant and fragrant odor. They consist of manmade mixtures of aromatic chemicals and essential oils. The 1939 Nobel Laureate for Chemistry, Leopold Ružička stated in 1945 that "right from the earliest days of scientific chemistry up to the present time, perfumes have substantially contributed to the development of organic chemistry as regards methods, systematic classification, and theory."
An essential oil is a concentrated hydrophobic liquid containing volatile chemical compounds from plants. Essential oils are also known as volatile oils, ethereal oils, aetheroleum, or simply as the oil of the plant from which they were extracted, such as oil of clove. An essential oil is essential in the sense that it contains the essence of the plant's fragrance—the characteristic fragrance of the plant from which it is derived. The term "essential" used here does not mean required or usable by the human body, as with the terms essential amino acid or essential fatty acid, which are so called because they are nutritionally required by a living organism.
Lavender oil is an essential oil obtained by distillation from the flower spikes of certain species of lavender. There are over 400 types of lavender worldwide with different scents and qualities. Two forms of lavender oil are distinguished, lavender flower oil, a colorless oil, insoluble in water, having a density of 0.885 g/mL; and lavender spike oil, a distillate from the herb Lavandula latifolia, having a density of 0.905 g/mL. Like all essential oils, it is not a pure compound; it is a complex mixture of phytochemicals, including linalool and linalyl acetate.
Thymol, C10H14O, is a natural monoterpenoid phenol derivative of p-Cymene, isomeric with carvacrol, found in oil of thyme, and extracted from Thymus vulgaris, ajwain, and various other plants as a white crystalline substance of a pleasant aromatic odor and strong antiseptic properties. Thymol also provides the distinctive, strong flavor of the culinary herb thyme, also produced from T. vulgaris. Thymol is only slightly soluble in water at neutral pH, but it is extremely soluble in alcohols and other organic solvents. It is also soluble in strongly alkaline aqueous solutions due to deprotonation of the phenol. Its dissociation constant (pKa) is 10.59±0.10. Thymol absorbs maximum UV radiation at 274 nm.
Steam distillation is a separation process that consists of distilling water together with other volatile and non-volatile components. The steam from the boiling water carries the vapor of the volatiles to a condenser; both are cooled and return to the liquid or solid state, while the non-volatile residues remain behind in the boiling container.
Rose oil is an essential oil that is extracted from the petals of various types of rose. Rose ottos are extracted through steam distillation, while rose absolutes are obtained through solvent extraction, the absolute being used more commonly in perfumery. The production technique originated in Greater Iran. Even with their high price and the advent of organic synthesis, rose oils are still perhaps the most widely used essential oil in perfumery.
β-Pinene is a monoterpene, an organic compound found in plants. It is the less abundant of the two isomers of pinene, the other being α-pinene. It is a colorless liquid soluble in alcohol, but not water. It has a woody-green pine-like smell.
Fragrance extraction refers to the separation process of aromatic compounds from raw materials, using methods such as distillation, solvent extraction, expression, sieving, or enfleurage. The results of the extracts are either essential oils, absolutes, concretes, or butters, depending on the amount of waxes in the extracted product.
A florentine flask, also known as florentine receiver, florentine separator or essencier, other shapes called florentine vase or florentine vessel, is an oil–water separator fed with condensed vapors of a steam distillation in a fragrance extraction process.
Eau de toilette is a lightly scented perfume. It is also referred to as aromatic waters and has a high alcohol content. It is usually applied directly to the skin after bathing or shaving. It is traditionally composed of alcohol and various volatile oils. Traditionally these products were named after a principal ingredient, like geranium water, lavender water, lilac water, violet water, spirit of myrcia and "eau de Bretfeld". Because of this, eau de toilette was sometimes referred to as "toilet water".
Jeanne Rose was an herbalist and aromatherapist who changed the practice of American herbalism when she began her public work in 1969 with the publication of her first book, Herbs & Things: Jeanne Rose's Herbal. She began her herbal career in California as an undergraduate with studies in botany and science and a degree from San Jose State College. She went on to graduate work in marine biology and ecology. In 1969, she wrote the first modern book of herbalism, Herbs & Things. She taught herbs and aromatherapy at the University of California Extension throughout the 1970s and privately throughout the United States. She has lived in San Francisco since 1967 and established a herbal/aromatic garden and study center. Becoming concerned about the environment and the production of aromatic plants, she organized the aromatherapy industry and a group, The Aromatic Plant Project, to support local and organic production of aromatic plants, to provide resources for growers and distillers, to ensure high quality aromatherapy products and to educate consumers as to the appropriate and beneficial uses of these aromatic products.
Attar, also known as ittar, is an essential oil derived from botanical or other natural sources. Most commonly these oils are extracted via hydrodistillation or steam distillation. The Persian physician Ibn Sina was the first to derive the attar of flowers from distillation. Attar can also be expressed by chemical means but generally natural perfumes which qualify as attars are distilled with water. The oils are generally distilled into a wood base such as sandalwood and then aged. The aging period can last from one to ten years depending on the botanicals used and the results desired. Technically attars are distillates of flowers, herbs, spices and other natural materials such as baked soil over sandalwood oil/liquid paraffins using hydrodistillation technique involving a still and receiving vessel. These techniques are still in use at Kannauj in India.
Cymbopogon citratus, commonly known as West Indian lemon grass or simply lemon grass, is a tropical plant native to South Asia and Maritime Southeast Asia and introduced to many tropical regions.
Sandalwood oil is an essential oil obtained from the steam distillation of chips and billets cut from the heartwood of various species of sandalwood trees, mainly Santalum album and Santalum spicatum.
Aromatherapy is a practice based on the use of aromatic materials, including essential oils and other aroma compounds, with claims for improving psychological well-being. It is used as a complementary therapy or as a form of alternative medicine, and typically is used via inhalation and not by ingestion.
Bergamot essential oil is a cold-pressed essential oil produced by cells inside the rind of a bergamot orange fruit. It is a common flavouring and top note in perfumes. The scent of bergamot essential oil is similar to a sweet light orange peel oil with a floral note.
Ganjam Kewda Rooh is a plant native to the Indian state of Odisha primarily in the Ganjam district. Kewda has been identified as a Geographical Indications in India.