Herbal distillates, also known as floral waters, hydrosols, hydrolates, herbal waters, and essential waters, are aqueous products of hydrodistillation. They are

colloidal suspension A colloid is a mixture in which one substance consisting of microscopically dispersed insoluble particles is suspended throughout another substance. Some definitions specify that the particles must be dispersed in a liquid, while others exte ...

s of

essential oil An essential oil is a concentrated hydrophobic liquid containing volatile (easily evaporated at normal temperatures) chemical compounds from plants. Essential oils are also known as volatile oils, ethereal oils, aetheroleum, or simply as the o ...

s as well as

water-soluble In chemistry, solubility is the ability of a substance, the solute, to form a solution with another substance, the solvent. Insolubility is the opposite property, the inability of the solute to form such a solution. The extent of the solub ...

components obtained by

steam distillation Steam distillation is a separation process that consists in 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 re ...

or hydrodistillation (a variant of steam distillation) from plants and herbs. These herbal distillates have uses as

flavoring A flavoring (or flavouring), also known as flavor (or flavour) or flavorant, is a food additive used to improve the taste or smell of food. It changes the perceptual impression of food as determined primarily by the chemoreceptors of the g ...

s and

cosmetics Cosmetics are constituted mixtures of chemical compounds derived from either natural sources, or synthetically created ones. Cosmetics have various purposes. Those designed for personal care and skin care can be used to cleanse or protec ...

. Common herbal distillates for

skincare Skin care is a range of practices that support skin integrity, enhance its appearance, and relieve skin conditions. They can include nutrition, avoidance of excessive sun exposure, and appropriate use of emollients. Practices that enhance appea ...

include

rose water Rose water ( fa, گلاب) 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 fla ...

, orange flower water, and

witch hazel Witch-hazels or witch hazels (''Hamamelis'') are a genus of flowering plants in the family Hamamelidaceae, with three species in North America ('' H. ovalis'', '' H. virginiana'', and '' H. vernalis''), and one each in Japan ('' H.&nb ...

Rosemary ''Salvia rosmarinus'' (), commonly known as rosemary, is a shrub with fragrant, evergreen, needle-like leaves and white, pink, purple, or blue flowers, native plant, native to the Mediterranean Region, Mediterranean region. Until 2017, it was kn ...

oregano Oregano (, ; ''Origanum vulgare'') is a species of flowering plant in the mint family Lamiaceae. It was native to the Mediterranean region, but widely naturalised elsewhere in the temperate Northern Hemisphere. Oregano is a woody perennial ...

, and

thyme Thyme () is the herb (dried aerial parts) of some members of the genus ''Thymus'' of aromatic perennial evergreen herbs in the mint family Lamiaceae. Thymes are relatives of the oregano genus '' Origanum'', with both plants being mostly indigen ...

are hydrosols that may be used in food manufacturing.

Production

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 is 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. The produced herbal waters are essentially diluted essential oils at less than 1% concentration (typically 0.02% to 0.05%). Several factors, such as temperature and an 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.

Usage

Distillates are used as flavorings, cosmetics and as herbal treatments. Herbal distillates are less concentrated than essential oils, possibly making them more suitable for some topical uses.

Science

The science of distillation is based on the fact that different substances vaporise 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 Plants are predominantly photosynthetic eukaryotes of the kingdom Plantae. Historically, the plant kingdom encompassed all living things that were not animals, and included algae and fungi; however, all current definitions of Plantae excl ...

pigment A pigment is a colored material that is completely or nearly insoluble in water. In contrast, dyes are typically soluble, at least at some stage in their use. Generally dyes are often organic compounds whereas pigments are often inorganic compou ...

s and

flavonoid Flavonoids (or bioflavonoids; from the Latin word ''flavus'', meaning yellow, their color in nature) are a class of polyphenolic secondary metabolites found in plants, and thus commonly consumed in the diets of humans. Chemically, flavonoids ...

s. 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. Herbal distillates degrade over time and will degrade faster than essential oils, which are more stable and will degrade slower. 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

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in popular herbal distillates, this has not shown to be the case.

References

Books

* Firth, Grace. Secrets of the Still. Epm Pubns Inc; First edition (June 1983) * Price, Len and Price, Shirley. Understanding Hydrolats: The Specific Hydrosols for Aromatherapy: A Guide for Health Professional. Churchill Livingstone 2004 * Rose, Jeanne. 375 Essential Oils & Hydrosols. Frog, Ltd, Berkeley, CA, 1999. * Rose, Jeanne. Hydrosols & Aromatic Waters. Institute of Aromatic & Herbal Study, 2007. {{Perfume Distillation Herbs Essential oils Flavor technology Herbalism Cosmetics Perfume ingredients Pharmacognosy

Production

Usage

Science

See also

References

Books