Methods for obtaining essential oils from plants. aromatic plants

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10.2. METHODS FOR OBTAINING ESSENTIAL OILS

The above properties of fragrant oils have been used in various methods of obtaining from ethereal plants and their subsequent purification. Essential oils in most cases are produced from fresh raw materials ( green mass geraniums, lavender flowers). But some oils are obtained from dried (mint), dried (calamus and iris roots) or pre-fermented (rose flowers, iris roots, oakmoss) raw materials.

There are many different ways to obtain essential oils. Some of them have been used since time immemorial, others are more modern and therefore much more productive. Preference should be given to gentle methods, since aromatic oils are very "sensitive" and easily volatilize. With careless and improper handling, their quality deteriorates noticeably, so careful adherence to technology is necessary condition upon receipt of oils. If essential oils are contained in the form of glycosides, then they must be released by enzymatic cleavage to a free state, otherwise it cannot be obtained. For this, enzymes contained in the plant itself are used. First, the raw materials are crushed and triturated with water. Then at a temperature of 50-60ºС insist for several hours: in this time runs breakdown of glycosides and fragrant substances are formed.

Depending on the nature of the raw materials and the basic properties of the oils, one or another method is used to extract them, which allows obtaining the highest yield and the best quality.

1. If the essential oil is found in large quantities in large containers (for example, in the pericarp of citrus fruits), then use pressing or squeezing method, i.e.mechanical way.

2. If there is a relatively large amount of fragrant oil in the raw material and the oil is thermostable, then use distillation methods, namely:

a) water distillation method; b) steam distillation method;

c) steam distillation method at elevated pressure; d) steam distillation method at reduced pressure.

3. If the components of the oil are thermolabile and undergo degradation, then use extraction methods. Distinguish:

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a) extraction with low-boiling solvents (ethyl ether, methylene chloride, petroleum ether, acetone, etc.);

b) extraction with liquefied gases (propane, butane, carbon dioxide); c) extraction with fats (maceration of flower raw materials fatty oil With

heating and without it).

4. For heat-labile oils, the so-called absorption methods which can be divided into:

- enfleurage - the essential oil released from freshly harvested raw materials (mainly from flowers) is absorbed by solid high-quality fats;

– dynamic sorption– absorption of oils by sorbents (activated carbon, silica gel).

The final products obtained in the first two methods are called essential oils, in the third - extractive essential oils.

and at the fourth - flower lipsticks.

mechanical way. Using this method, only fragrant oils of citrus fruits (lemon, orange, mandarin, bergamot) are obtained, where the oils are concentrated only in their peels in fairly large receptacles. Until 1930, they were obtained by pressing the peel into a sponge. At present, it is common to remove the peel, pass it through toothed rollers, mix with large quantity water, and then subjected to pressing on hydraulic presses. The essential oil remaining (about 30%) in the peel is further extracted by steam distillation. In this case, the heating of the product must not be allowed, since this will destroy important volatile compounds. The yield of oils with this method (out of 1000 fruits, g):

distillation method. Steam distillation is the most common way to obtain essential oils. This method is used when the raw material contains a relatively high oil content and when the distillation temperature (about 100° C) does not affect the quality finished product. The distillation method is quite simple, but for each type of raw material it requires the selection of conditions - temperature, pressure, process duration. Cro-

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In addition, additional separation of oils from distillation waters is possible. During hydrodistillation, the source of water vapor is water poured into the apparatus along with the processed material: essential oil or essential oil.

romaine raw materials. But in most cases of obtaining aromatic oils, water vapor is used, supplied to the apparatus from a steam generator (the so-called steam distillation).

The boiling point of individual components of essential oils ranges from 150 to 350 ° C. For example, pinene boils at 160 ° C, limonene - at 177 ° C, geraniol - at 229 ° C, thymol - at 233 ° C. However, all these substances distilled below 100°C in the presence of water vapor.

The theoretical foundations of the steam distillation process follow from Dalton's law of partial pressures, according to which a mixture of liquids (mutually insoluble and not chemically acting on each other) boils when the sum of their vapor pressures reaches atmospheric pressure.

According to Dalton's law total pressure mixture is equal to the sum of the partial pressures of the components. As a result, the vapor pressure of the mixture reaches atmospheric pressure even before the water boils. So, for example, a mixture fir oil and water at atmospheric pressure will distill at 95.5°C (instead of 160°C for pinene, the main component of fir oil).

Steam distillation is carried out in continuous or batch distillation apparatuses, container-type distillation apparatuses, etc.

Often, to avoid decantation of raw materials and destruction constituent parts oils (saponification of esters, etc.), the raw material is placed on perforated grids, the lower of which is above the condensate level, and distilled off with live steam. The distillate (a mixture of water and essential oil) is cooled in a refrigerator and the so-called decanted oil is separated, and the distillation waters are distilled again, heated with dull steam or subjected to additional treatment with activated carbon and volatile solvents. With this method, fragrant water is simultaneously obtained.

On fig. 10.1 shows a diagram of a batch distillation plant, which consists of a cube 4, a condenser 15 and a receiver 19. The cube is protected by a steam jacket 3, equipped with a perforated bubbler coil 6 for starting live steam; has a drain cock 7 and is closed from above with a lid 1 with

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steam pipe 2, through which it is connected to the condenser.

Rice. 10.1. Installation for the production of essential oils by steam distillation

With the help of winch 13 lift the cube cover. In a cube on a false bottom 5 and a layer of cloth 18, vegetable raw materials are placed, which, if necessary, are soaked with water. The lid is then lowered and hermetically connected to the body using bolts or a clamping device. Steam 12 is let in through valve 9 into the steam jacket, and exhaust steam and condensate are released through valve 10, which pass through the steam trap 11 into the sewer. After sufficient heating of the plant material through the valve 8 and the bubbler 6, live steam is let into the cube, which evenly passes through the plant mass and entrains the essential oil. Vapors of ethereal condensate enter the receiver. The cooled water enters the condenser from below through valve 16, and the waste water exits from above through valve 17. After the distillation is completed, valves 8 and 9 are closed, the cube is allowed to cool, the liquid is drained through valve 7, the lid is lifted and the cube is unloaded, overturning it using a gear mechanism fourteen.

The receiver is the so-called Florentine bottles with drain pipes for water. They are arranged in such a way that if oil is lighter than water, then it is collected in a layer from above, and water flows out through a drain pipe, which is fixed in a tube at the bottom of the bottle (Fig. 10.2). If the essential oil is heavier than water, then it sinks to the bottom, and the water is removed through a tube fixed at the top of the bottle.

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Fig.10.2. Florentine bottles:

1 - for essential oils lighter than water, 2 - for essential oils heavier than water

In cases where the distillation (running water) obtained after separating the oil contains a lot of valuable essential oil in a dissolved or emulsified state (for example, when obtaining rose oil), the latter is isolated from it by cobation. The cobation process consists in the fact that distillation waters are distilled for the second time, while with the first portions most of retained oil.

Continuously operating distillation apparatuses are used to process large quantities of raw materials. Steam distillation can be carried out not only at atmospheric pressure, but also under pressure with superheated steam. In this case, the ratio of water and oil favorably changes in favor of increasing the distilled oil. This is explained by the fact that the decrease in the elasticity of water vapor is stronger, not proportional to the change in the elasticity of the vapor of the essential oil.

When obtaining fragrant oil by steam distillation, individual parts of plants (flowers, leaves, seeds, stems, roots) can be used both in raw and dried form. It is better to use dried leaves as they are easier to grind and provide a fuller extraction. The duration of distillation is about 2 hours. The distillation should not be carried out too quickly, since part of the steam is used involuntarily, and the oil is emulsified.

The yields of essential oils (in %) during steam distillation vary greatly depending on their content in the fragrant parts of plants:

Due to the cheapness and simplicity of the equipment in this way,

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tea most oils. However, significant disadvantages should be noted:

– relatively high distillation temperature for some aromatic substances included in this essential oil, which sometimes causes their decomposition;

– the solubility of some aromatic substances in water during its condensation from water vapor, and therefore, these aromatic substances are absent in the composition of the oil after settling;

– insufficiently high distillation temperature for some of the hardly volatile aromatic substances that make up this essential oil, as a result of which these substances are not distilled off from plant materials and, therefore, are absent in the composition of the distilled oil;

– the presence in most aromatic oils of terpenes and sesquiterpenes, which reduce their solubility in alcohol, and in some cases their smell. So, for example, sesquiterpenes have a special, specific camphor smell, which differs from the main smell of the essential oil, but often harmonizes with it.

Thus, the oils obtained by steam distillation do not have such a natural smell as the essential oil directly in the plant. So, for example, it has not yet been possible to obtain satisfactory oils from such flowers as lily of the valley, jasmine, lilac, etc. by this method. The last drawback can be eliminated by the so-called detoxification method (distillation in a vacuum or hydrovacuum, hydrodistillation, treatment with alcohol of reduced strength).

In the distillation of essential oils, terpenes are distilled first and therefore can be easily separated from the odor constituents distilled at a higher temperature. Sesquiterpenes are most often distilled off last. During distillation, a certain amount of the main odor carrier is carried along with terpenes, depending on the method of distillation and fraction. Sterpenic oils are characterized by:

1) greater solubility in water and alcohol; 2) greater strength, that is, the concentration of the main smell;

3) the property to immediately give transparent and remaining transparent alcohol solutions.

These benefits of such oils are used in perfumery. So in

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alcohol can completely dissolve only non-terpene citrus oils. When designating such oils, the prefix D (for perfumes) is used. However, very often in such an oil there is some change in smell, which does not correspond to freshness and integrity. natural oil containing terpenes. Sterpenic oils should not be used in medicine, since the desired therapeutic effect is observed only when using essential oils with the most complete composition, i.e. contain as many active ingredients as possible.

Extraction Method began to be used from the second half of the nineteenth century. Unlike the previous ones, this method requires more sophisticated equipment. A well-purified solvent is also required.

Essential oils are soluble in many organic solvents. This property is used in cases where the components of the oil are thermally labile and undergo degradation during steam distillation.

As solvents are used: ethanol, benzene, chloroform, methyl alcohol, acetone, liquid or gaseous butane, carbon dioxide. But the most commonly used petroleum ether (liquid petroleum product, a mixture of light hydrocarbons).

The equipment used is very diverse. Basically, it consists of an extractor, a distillation cube with a refrigerator, into which a solvent with oil comes from the extractor.

During extraction, the raw material is poured one or several times with a solvent, which, after saturation with aromatic substances, is drained from the raw material. From the drained extract, called a micelle, the solvent is removed under pressure, then under vacuum. The resulting essential oils are called extraction or "odorous waxes" (Essences concretes) and in their smell they are closer to the essential oils found in plants than oils obtained by steam distillation. This is especially true for raw materials with a pleasant smell, which, when distilled with water vapor, give too little oil (rose, daffodil, violet, carnation).

However, the solvent extracts from plants not only aromatic oils, but also waxes, paraffins, gums and fats, so the primary extraction products have a solid consistency and are not completely soluble in alcohol. Such oils are called concretes.

For release from ballast substances of specific oils, the latest

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are extracted again with ethyl alcohol, and after its distillation and filtration with cooling, secondary extraction products are obtained, called absolute oils or absolute. Absolute oils are completely soluble in alcohol; they are also devoid of terpenes and sesquiterpenes. When using ethyl alcohol as an extractant this form called a rhizinoid. This type of extraction is used in the production of essential oils from various plants:

the yield of specific oils is from 0.08 (tuberose) to 0.98% (ylang-ylang); the yield of absolute oils is from 0.18 (tuberose) to 80% (ylang-ylang). Generally, essential oils extracted with organic solvents do not

used internally to avoid an allergic reaction and a weakening of the immune system due to the fact that the solvents are highly toxic, and their separation from the essential oil is incomplete. For ingestion, essential oils extracted with ethanol are allowed, the admixture of other solvents is allowed in an amount of not more than 5 parts per million parts of the main substance.

The extraction methods for obtaining fragrant oils should also include maceration with fats. To do this, raw materials in fabric bags are immersed in a container with fat for 24-48 hours at a temperature of 50-70 ° C. This operation is repeated 10-15 times until a smell of a certain strength is obtained. Usually animal fats are used - beef or pork, and from vegetable - olive oil. Sometimes paraffin with a melting point of 60 ° C is used. Fats and oils must be clean, odorless and prepared according to a special recipe. Next, the oil is extracted with alcohol (see enfleurage).

AT recent times developed and widely used for the extraction of essential oils cryogenic method using pressurized gases.

The enfleurage method (from the French enfleurer - to convey a floral aroma) is the most ancient. In this way, jasmine, lily of the valley, tuberose (raw materials with low content essential oils).

The method is based on the ability of essential oils released by plants (mainly from flowers) to pass into the gas phase and then be absorbed by fats and sorbents. This process is carried out in special frames-chassis (size 5×50×50), hermetically assembled by 30-40 pieces (one on top of the other) into a battery. In the middle of such a frame is a glass plate, on which

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adsorbent is applied on both sides. On an adsorbent (activated carbon or a mixture of pork and beef fat, etc.) with a thickness of about 3-5 mm, spread flowers (without cups) up to 3 mm thick, and the edges of the plate remain uncovered by 4 cm. To increase the fat absorption surface, grooves are made with a spatula. Within 1-3 days, the evaporating essential oils are absorbed by the adsorbent. Then the raw materials are removed and fresh raw materials are placed on the frames. This operation is carried out repeatedly (up to 30 times) until the adsorbent is completely saturated with essential oil. Since the waste raw material still contains a certain amount of essential oil (heavy fractions), it is additionally processed by extraction. And the fat saturated with essential oil is then scraped off the glass.

This product with a sufficiently high odor quality is marketed under the name flower lipstick. Fragrant oil is extracted from flower lipstick with alcohol. The alcohol extract is frozen and the precipitated impurities are removed by filtration. Then the alcohol is distilled off in a vacuum and pure essential oil is obtained.

At present, the enfleurage method is rarely used. This is primarily due to high price final product (for example, 700 g of essential oil is obtained from 1 ton of rose petals).

Method dynamic sorption is essentially an improved method of enfleurage. Raw materials (flowers picked early in the morning) are placed in the chamber on the nets. Then the chamber is hermetically sealed and heated air is blown through it, which, capturing the vapors of essential oils, passes through activated carbon or silica gel, where the absorption (sorption) of the aroma oil vapors of the loaded flowers takes place. By extracting a sorbent (silicone or activated carbon), essential oil is isolated, after which the ether is distilled off from the solution and pure essential oil is obtained, close to absolute oil. This method is promising and is becoming more widespread.

Received various methods Raw essential oils can be subjected to various technological processing. To improve the quality of aromatic oil, it is purified to remove some unwanted compounds from it. This purification is carried out by distillation of the oil under reduced pressure and is called vacuum distillation. In the case of removing mono- and/or sesquiterpene hydrocarbons, this process may be referred to as "deterpenization". Sometimes volatile components are distilled off (fat aldehydes,

Herbal essences, essential (aromatic) oils are natural substances that have a strong effect and have various beneficial properties. They are well absorbed, which is important in such areas of cosmetology as skin care for the face, body and head. René Fürterer, a recognized botanist who devoted much time to research aromatic oils, in this article I tried to give answers to the questions: where are these oils found, how are they extracted and what are their properties?

How did the name "aromatic oils" come about? Essential oils, essences, volatile oils are all terms denoting substances that belong to the same class and have similar physical characteristics. Has much in common and chemical composition various oils. These substances plant origin they are volatile, have a strong odor, are soluble in fat and other vegetable oils or organic solvents, and, conversely, are insoluble in water. Due to their ability to dissolve, these substances were classified as oils, and the presence of a strong aroma made it possible to classify them as essences. However, they are different from substances such as pumpkin seed oil, palm oil or sesame oil. Many oils have found use for their medicinal properties, some of which are used in the food industry as spices and flavorings. And of course, largest areas use of aromatic oils remain perfumery and cosmetology, using medicinal properties and pleasant aroma of these substances.

From plant to essence

Aromatic oils are widely represented in the plant world, but there are about fifty plant families that synthesize them better than others: for example, plants of the labiate family (mint, lemon balm, thyme, lavender). Aromatic oils can be concentrated in various parts plants: in grains (anise, nutmeg), roots (ginger), wood (sandalwood, rosewood), leaves (lemon, eucalyptus) and finally in flowers (rose, orange blossom) and fruits. Essential oils are found in their pure form or are synthesized in the so-called essential oil cells located in excretory sacs, hairs or canals located close to the surface of the plant. Essential oils are obtained by grinding plants. The composition of essential oils can vary depending on the part of the plant in which it is synthesized. Consider, for example, a bitter orange. Its peel contains the aromatic oil "essence of curacao", in the leaves and small fruits - "the essence of small grains of bitter orange", in the flowers - "essence of Neroli", named after the Italian princess who invented this fragrance. The composition of the essential oil of any plant can vary indefinitely, depending on which variety this plant belongs to. Thyme can be considered a striking example of such diversity. In addition, the change in the composition of the essential oil is affected by the stage of the plant's life cycle at which it was processed. The composition of the oil is also influenced by the applied agricultural technologies and the type of soil - these factors contribute to the emergence of essential oils with ever new aromas. With the further use of oils, it is necessary to accurately determine their activity as components in various mixtures, therefore constant control for the quality of the resulting oil is an integral part of the technological process.

Oil Extraction Method

There are several ways to obtain aromatic oil. The choice depends on how the resulting oil will be used in the future. The currently known technologies are based on the properties of volatility and insolubility of essences. It should be clarified that there are two main types of essences: "hot" aromatic oils (thyme, pine), and "cold" (mint, eucalyptus). They are distinguished not by the method of obtaining, but by the effect they produce (feeling cold or warm).

Enphelange

This method of extracting plant essence is one of the most ancient, but is rarely used today. Shredded plants (most often flowers) are placed on a layer of fat, then the aromatic essence flows from the flowers into the fat, dissolving in it. During the enfleurage, fresh flowers are constantly added, resulting in a "flower paste" rich in aromatic oils. Often, when extracting an aromatic oil, organic solvents are used, which are then included in the composition of the resulting oil, which is not always desirable.

Steam distillation

Often resorted to distillation with water vapor. The plant is steamed to extract the aromatic oil from it. Further, during the cooling process, the steam condenses, while the oil is separated from the water. it modern technology and its advantage is that the use of organic solvents that otherwise remain in the oil can be avoided. This technology allows to increase the purity of the resulting product and preserve its natural composition.

There is a great variety of aromatic oils, each of which has a different effect on human body. When used topically, two of the most important properties that many oils possess to varying degrees.

antiseptic property

Depending on its composition, various oils destroy one or another harmful microorganisms. So, tea tree adversely affects yeast bacteria (in particular, Pityrosporum ovale), which cause dandruff. Some aromatic oils, such as thyme oil, can be detrimental to several types of bacteria. Due to these properties, aromatic oils are widely used as antiseptics.

Excitatory property

Many oils, when applied externally, have a stimulating effect and cause redness of the skin, which is due to increased blood circulation, which also causes a feeling of warmth.

Fragrances

Now let's talk about smells.

Lemon

Lemon is practically the only tree on which you can see leaves, flowers and fruits at the same time. This, of course, is a tree grown in warm regions, for example, on the Mediterranean coast of France. A young lemon tree reaches 5 meters in height. The leaves are quite large, pale green. Flowers have pleasant aroma and cover the tree all year round. Fruit picking takes place in summer and winter. Harvest from one adult lemon can be up to 2,000 fruits. Lemon essence is obtained by steam distillation of fresh or pressed zest. The resulting oil has a light yellow, sometimes greenish tint and a very pleasant smell. Evaporation lemon oil have a strong antiseptic effect.

Cypress

Cypress is found on the entire Mediterranean coast in the form of protective forest plantations. However, Asia is considered the birthplace of this tree: China, Iran, Afghanistan. It came to Europe several thousand years ago. Cypress can reach 20 meters in height. Latin name cypress "sempervirens". The bark is gray, with a reddish tint; small leaves-needles - triangular in shape. Cypress cones contain tannins - substances with astringent properties - as well as a colorless or greenish essence that smells like turpentine. Cypress oil is obtained by steam distillation. It has antiseptic properties.

Eucalyptus

Lavender

The name of this plant comes from the Latin verb "lavare", meaning "to wash". In ancient times, the Greeks and Romans used lavender for hygienic purposes - it was valued for its pleasant smell, and also as an antiseptic. Lavender belongs to a large family of labiales. It is a semi-shrub that blooms in July-August with blue flowers (lavender color: lilac-blue) located on a flowering stem. Lavender is widely distributed in the Mediterranean - there are both wild thickets and cultivated plantings. The oil is extracted from the inflorescences. Also, lavender repels insects (moths and bedbugs) - linen stored in cabinets is shifted with small bouquets of dry lavender.

Tea tree

The tea tree (Melaleuca alternifolia, also called "tea tree") is native to Australia. It grows in swampy areas on the east coast of New South Wales. It was first described by Joseph Banks, who participated in the expedition of Captain Cook. Tea tree was one of the main medicines of the early white settlers of Australia. Due to its antiseptic properties, it helped in the treatment and disinfection of boils and various wounds. The oil of this tree was considered so valuable that the workers involved in its collection were released from military service until they collected enough of it to provide for the Royal Australian Navy and army. Wetlands, venomous snake bites, scorching sun and sudden downpours made picking leaves difficult. tea tree in which the oil is concentrated. The tea tree reaches no more than 6 meters in height. Leaves are narrow, small cavities containing essence. The inflorescences are an asymmetrical spike. The oil obtained by steam distillation has antiseptic properties. It is especially effective against fungi and yeast bacteria. Tea tree oil is an excellent remedy for the Pityrosporum ovale bacteria that causes dandruff.

Peppermint

There are many varieties of mint and its hybrids. Peppermint is especially popular in French pharmaceuticals. Mint is native to most of the European south. Mint became widespread thanks to the Romans, who appreciated its freshness. In ancient times, mint was believed to relieve headaches. Its analgesic effect was used in the treatment of various ailments: toothache, inflammation of the sciatic nerve, itching caused by urticaria or eczema, nervous itching. Chinese doctors also used mint in a similar way. Peppermint - perennial grass with a square stem: hallmark any plant belonging to the mint family. The leaves are simple, toothed. Flowers are purple or white. The oil is obtained by steam distillation. Thanks to its refreshing effect, it is highly valued in the confectionery industry (sweets, chewing gum), production of soft drinks. It is used in pharmaceuticals due to its analgesic properties: it stimulates the nerve endings that feel cold, thereby causing partial anesthesia. It is used, in particular, in the treatment of itching of various origins. Peppermint also finds use in modern medicine as an antispasmodic antiseptic also used as an aphrodisiac.

sweet orange

China is considered the birthplace of this tree, reaching a height of 3 to 13 meters. The leaves are smooth, shiny, oval. The flowers are white, less fragrant than those of the bitter orange. This is because they contain less aromatic oil. Sweet orange is the most common of all citrus fruits (lemon, mandarin, bitter orange, bergamot, etc.). It is grown for the fruits used in the food industry, as well as for the production of aromatic oil, which is obtained from the peel (after pressing the fruit) by steam distillation. The oil has a fairly rich yellow color. With the ripening of fruits, the concentration of oil in them decreases. Sweet orange essence, known as "Portuguese Orange", is found in many colognes. As an antiseptic, it is used in the manufacture of lotions and ointments. Due to this property, as well as a pleasant smell orange oil included in many cosmetic preparations.

forest pine

The forest pine differs from its relative, the maritime pine, which provides man with turpentine and other products of tapping (artificial wounding of growing trees to obtain softwood resin), pink bark, shorter needles, and smaller cones. Wild pine contains a lot of oil, which is obtained from the buds by steam distillation. Wild forest pine is found in the Alps and the Pyrenees at an altitude of 800 to 2,000 meters; in the flat terrain there are only artificial plantings. Forest pine grows in Europe and North Asia and reaches 45 meters in height. Permanent leaves (needles) are 3 to 6 cm long. They, like the buds, contain oil obtained by steam distillation. pine oil known for its antiseptic action. It is used orally to treat the respiratory tract.

Rosemary

The name of this plant, derived from two Latin words: "ros" and "marin", meaning "sea dew". The birthplace of rosemary is the Mediterranean coast, where it has long been considered a plant that patronizes love, fidelity and friendship. Rosemary is an evergreen shrub reaching 2 meters in height. The leaves are narrow, dark green above, gray and rough with reverse side. The edges of the sheet are folded down. The flowers are pale blue, clustered inflorescences are located at the ends of the branches. The oil is extracted from the inflorescences and leaves by steam distillation. Rosemary is used in various fields, and, above all, as a spice. The aromatic oils contained in rosemary have antiseptic properties and promote the speedy healing of wounds. They are used in the manufacture of medicinal alcohol solutions. Rosemary belongs to medicinal plants and is used in the treatment of wounds and bruises. rosemary oil It is a pale yellow or colorless liquid with a camphor smell and a pronounced taste. As an antiseptic it is part of various preparations.

Sage

Latin name sage Salvia- comes from the verb salvere, meaning to save, heal, which emphasizes the significance of this medicinal plant. The antiseptic properties of sage are especially highly valued. A medieval proverb said: “Man, why are you on your deathbed when sage grows in your garden?” Sage is a semi-shrub that reaches 20 to 80 cm in height. The leaves are persistent, pale green in color, covered with white fluff. Large purple-blue flowers appear from May to August. Sage is widely distributed in the Mediterranean, but is sometimes found far from the coast. It belongs to medicinal plants, is used for external use in the treatment of wounds and bruises, sprains and frostbite. Sage infusion is used to improve hair growth, but sage is primarily known as an antiseptic.

Thyme

Thyme is widely used as a condiment, but its use is not limited to the culinary field. Thyme is known to soothe and cure headaches and help with anemia: it is recommended to eat a sugar cube with a few drops of thyme oil. As an external agent, thyme oil, as a stimulant, is added to hot water when taking baths: it increases blood circulation and causes a feeling of warmth. In addition, this oil has antiseptic properties. Thyme is a dwarf shrub 7 to 30 cm high with flexible branches. The leaves are small, pointed. The flowers are pink and white. Oil is obtained only from leaves or inflorescences. There are 50 types of thyme, differing in botanical characteristics. In addition, many varieties of this plant are known, differing in the composition of the essential oil.

Verbena

The Romans and Gauls believed that this plant heals all diseases. The memory of this is preserved in the etymology of various names of verbena. The word "vervain" most likely comes from the Latin verb "verberare", meaning "to smash". It is possible, however, that the name "vervain" comes from the verb "vivere" - "to live." Verbena was often used in various rituals and religious ceremonies. Fragrant verbena is a shrub reaching 2 meters in height. The leaves are pointed, many small flowers make up an inflorescence-ear. Verbena blooms from July to August. From the dried leaves, verbena oil is obtained by steam distillation, which has a lemon smell and a yellow-green color. The oil is mainly concentrated in the leaves. Has antiseptic properties.

All, without exception, essential oils, subject to the dosage, have no side effects on the body, are not addictive, do not cause imbalance physiological processes organism.

Use in Everyday life aromatic oils makes it possible to always feel good. The main thing is not to expect that the natural essences of plants will immediately make a "revolution" in the body. Their main value is that health qualities plants are effective, but their effect on the body is delicate, gradual and moderate.

Methods for using essential oils

At home, you can quite simply and effectively use aromatic oils, both for cosmetic and medicinal purposes. They can be used as perfumes, for filling aromatic baths and used for the preparation of individual cosmetics. Aromatic oils will also help with some ailments and can become prophylactic against head pain, colds, muscle pain

Massage

The massage itself is both an invigorating and relaxing treatment, during which healing aromatic oils enter the bloodstream through the skin.

For supporting wellness it is recommended to do self-massage, paying special attention to the soles of the feet and palms. It is also useful to rub those areas of the body where discomfort is felt, for example, peppermint oil can be rubbed clockwise into the stomach area for indigestion, and marjoram helps to relax the muscles of the neck and shoulders.

Baths

Baths are the simplest and most enjoyable way to use aromatic oils. Aroma substances come into contact with the entire surface of the skin. Due to the high penetrating power, they are quickly absorbed by the skin. In addition to a strong effect on the skin, essential oils have a powerful effect on the lungs, intestines, kidneys, central and peripheral nervous system. Baths can be hot, cool, sitz, foot, hand and foot baths.

To do this, add 5-10 drops of oil to a filled bath. The procedure time is from 5 to 30 minutes. Increasing the time of taking the aroma bath should be gradual.

Aromatic baths traditionally considered one of the most sophisticated and sensual entertainment that was popular in ancient Rome. In addition to pleasure, they are very useful, helping to treat skin irritations, muscle pain, rheumatism, arthritis. Ylang-ylang has a relaxing effect; chamomile and lavender help with stress disorders and insomnia; rosemary and pine oils relieve pain in the limbs. When using bath oils, avoid those that irritate the skin.

Steam inhalation

This method is especially suitable for the treatment of runny nose, sore throat and chest cough. When inhaled, aroma substances have direct impact on the respiratory organs, eliminating congestive and inflammatory reactions. Add 5 drops of essential oil peppermint or thyme in a bowl of hot water, cover your head with a thick towel and inhale the hot steam for a minute. Rest a little, then repeat the procedure. The same inhalation can be done by sitting in hot tub with the addition of aromatic oil. The same method is suitable for a facial steam bath. Lemon or tea tree oils open pores well and cleanse the skin of the face.

Good day to all!

Today I invite you to get acquainted with what and how natural essential oils are produced. As I already wrote about myself (for those who haven’t read it, look at the page “”), I am a chemical engineer by education. Therefore, the topic of obtaining oils is very clear to me and I will try in simple words explain to you what is the value of high-quality oils, as opposed to cheap ones. After all, only high-quality essential oils can be used for aromatherapy.

First, let's talk about where essential oils come from and what they are. An essential oil is not an oil at all, but a complex multi-component mixture of various substances, sometimes up to 3000 components can be included in the composition of essential oils!

Just imagine! Is it possible to make such a mixture artificially? The quality of the oil and the strength of its impact largely depend on the proportion in which these components are present in the oil.

After all, good oil, like good wine, depends on the climatic conditions in which the plant grew, what the weather was like, on what soil, whether chemicals were used, etc. After all, oil can contain both very useful and harmful components. And the greater the percentage of precisely valuable components in raw materials, the oil is more valuable it will come out, although it is impossible to determine by smell.

By the way, in order to check the raw materials, and then the finished oil, you need to have a very well-equipped laboratory with the most modern equipment. And this, as you know, costs money. Therefore, high-quality oil cannot be cheap.

Well, now let's talk about where essential oils are found in plants? Oil is the soul of a plant. For example, citrus fruits - lemon, orange, grapefruit, tangerine - contain oil in the peel. This is what sometimes splashes in your eyes when you peel an orange. And in the eyes after that it stings. Therefore, it is necessary to avoid getting oils in the eyes. And citrus oils are obtained by squeezing or cold centrifugation.

And if an orange, for example, was treated with chemistry, what will we get? That's right, all this chemistry will be in the oil, and instead of health benefits, we will get one harm.

Oil can be obtained from plant leaves, flowers and stems. So many oils are obtained, for example, mint, eucalyptus, lemon balm, rosemary, lavender, etc.

And here the steam distillation method is mainly used. Steam distillation also produces oils from certain types of wood. If you know the principle of a moonshine still, then the principle is the same here.

Plants are placed in a container, steam is supplied from below, and a mixture of steam with essential oils comes out from above. The mixture then passes through special systems cooling and is divided into fractions - water and oil.

Everything seems to be simple. But let's discuss. Many tried moonshine, vodka, whiskey, rum. What is the difference? Alcohol is everywhere in the base, and the quality is completely different.

What influences? That's right, raw materials, water and the equipment on which the product is made. If we have already dealt with water and raw materials, then I will say this about the equipment, everything must be very clearly calculated in order to end up with oil with the highest yield of valuable components.

Remember, if moonshine is made by the most primitive method, then it has a whitish color, there are a lot of fusel oils. Likewise with essential oils. After the first distillation, a second distillation is usually carried out, for a more thorough purification.

In this regard, I cannot but say a few words about oils. These are oils produced by the Swiss company Elixan Aromatica, they differ you the highest degree of purification, made from selected raw materials using the most advanced technologies.

Their quality is evidenced by the fact that it is the oils of this company that are widely used in clinics and nursing homes in Switzerland, as well as in maternity wards. One of the main criteria for these places is air hygiene. The use of oils in such places has scientifically confirmed that essential oils are an effective method of healing the body and preventing diseases.

Oils can also be obtained from flower petals, for example, roses, jasmine, neroli, etc. Such oils are obtained mainly by the enfleurage method. To do this, take plates coated with special fat, and petals or leaves of plants are placed on them. Fat absorbs the smell, then the batch of petals changes, and so on several times. Then the fat is mixed with a special solvent, or alcohol, and then distilled.

The oils obtained by this method are very expensive and, as a rule, are not used in their pure form. But the packaging should always indicate the percentage of essential oil. There are some other specific acquisition methods, but they are less common.

There are several methods for obtaining essential oils from plant materials. The main ones are distillation, extraction with liquefied gases, enfleurage and maceration. In addition, at home you can make hydrolat and fruit powder. How to prepare essential oil at home in different ways, is described in detail in this material.

How to get essential oil at home

In order to obtain the essential oil from plants as pure as possible, the distillation method is used. Steam distillation (distillation) is used when there are a lot of essential oils in the plant or it is necessary to extract substances that are soluble only in water during prolonged boiling, for example, azulene from chamomile and yarrow. The oil obtained by distillation with steam is called distillation oil.

For some plants, the method of extracting essential oils with steam is not applicable (mignonette, narcissus, violet, heliotrope, levkoy, frankincense, hyacinth, lilac, etc.), therefore, extraction with volatile organic solvents is used. The most commonly used solvents are ethyl alcohol and purified petroleum ether. The extraction process consists of two stages. Before an essential oil can be prepared, the components must be extracted from the plant material and the solvent must be removed (often under reduced pressure). After being freed from the solvent, a semi-liquid or solid mass of dark color is obtained, which is called "concrete". The absolute (absolute) is extracted from the concrete with the help of alcohol. They are usually colored highly concentrated liquids, more viscous than essential oils.

Such a method of obtaining essential oils as extraction with liquefied gases (carbon dioxide and freon) is widespread. It allows you to carry out extraction and obtain concrete much more efficiently not only from essential oil crops, but also from any spicy-aromatic raw materials. Such extracts retain a bright aroma, taste and biologically valuable components of plants.

Pure essential oils obtained by any technology are very aggressive environments; if they get on the skin, they can cause necrosis. Therefore, they are sold diluted with base oils to a relatively safe concentration. Unfortunately, a huge amount of essential oils are now sold without specifying the method of obtaining, therefore, it is undesirable to use such products internally, and in other cases it is unsafe.

Currently, supercritical CO2 extracts are used. They are a complex complex biologically active substances: essential oils, terpenoids, fatty acids, phenol-containing compounds, vitamins, pigments, alkaloids, etc. These are ointment-like oily masses with a strong taste and smell characteristic of the feedstock. Completely soluble in oils, alcohol, acetic acid, are insoluble in water, but form strong emulsions with it.

How can you get essential oils at home? To do this, it is better to use the methods of enfleurage and maceration.

Enfleurage- this ancient method of extracting essential oil crops, which was carried out on solid fats in order to obtain solid perfumes, as well as with plants from which aromas cannot be extracted when heated (rose, jasmine and others). To prepare an essential oil with your own hands at home, the glass is covered with purified pork or beef fat, and freshly picked flower petals are laid out on top. Fat absorbs volatile essential oils. After 72 hours, the petals are replaced with fresh ones. The procedure is carried out until the fat is saturated with aroma, about 30 times. The fat is then collected and purified. To extract the essential oil from the lipstick, it is dissolved in alcohol and shaken constantly for 24 hours to separate the fat from the essential oil. The essential oil separated on the surface is decanted.

Maceration, infusion oils, infusions- a method for extracting active biological substances from plant raw materials by infusion in an extractant. For maceration, they are mainly used: vegetable oils and animal fats, water with glycerin, alcohol with water. The process can last from several hours to several weeks with regular mixing or agitation and constant replacement of raw materials (plants). Maceration for the manufacture of essential oil at home is carried out at room temperature or with low heat (in the sun), or with constant heat in the oven (languishing). The prepared mixture is filtered. Store any extraction products in small containers with a well-ground dark glass lid in the refrigerator or in a dark, cool place. This is especially true for oil and fat fractions, so that they do not oxidize when exposed to air when opened.

How is essential oil obtained by hot maceration? To do this, the petals in gauze bags are dipped for 48 hours in animal fat or vegetable oil heated to 45-50 ° C, then they are changed to fresh ones. After a multiple (20-25 times) change of raw materials, a sufficient amount of aromatic substances accumulates in the fat (oil).

The product obtained in the process of maceration and enfleurage is called flower lipstick if the extraction was carried out with solid fat or antique (incense) oil if the extraction was carried out with vegetable oil.

Essential oils for making macerates at home

Macerates, even from poisonous plants, are less dangerous than essential oils isolated from these plants.

Below is a list of essential oils for making macerates. All of them are distributed according to skin types. It is best to use cold-pressed oils for cosmetic purposes and not heat them more than 45 ° C during the maceration process.

Oils for all skin types:

• avocado,
• watermelon seeds, grape seeds, jojoba, sesame, poppy seeds,
• peach pits, wheat germ, wild rose.

Oils for dry skin:

• apricot,
• walnut,
• castor,
• corn,
• sea ​​buckthorn,
• peach,
• wheat germ, pumpkin.

Oils for oily skin:

• grape seeds,
• apricot kernels,
• almond,
• sunflower.

Essential oils for homemade macerate for dehydrated skin:

• apricot,
• avocado,
• coconut,
• almond,
• borage officinalis (borage).

Oils for baby skin:

• apricot,
• watermelon pits,
• jojoba,
• cocoa,
• coconut,
• sesame,
• mango bones,
• olive,
• peach.

Oils for aging and mature skin:

• amaranth;
• grape seeds,
• jojoba,
• macadamia,
• hemp,
• almond,
• sea ​​buckthorn,
• borage officinalis (borage),
• peach pits,
• sunflower,
• wheat germ,
• camelina,
• black cumin.

Oils for therapeutic massage with high penetrating power:

• avocado,
• grape seeds,
• jojoba,
• hemp,
• hazelnut,
• wheat germ.

Essential oils for homemade hair macerate:

• for all types of hair: avocado, watermelon pits, castor, pine nuts, hemp, corn, sesame, linseed, olive, peach pits, sunflower, burdock, pumpkin;
• for dry hair: jojoba, coconut;
• for oily hair: almond;
• in case of hair loss, the following essential oils are used to obtain macerate with their own hands: cedar, laurel, almond, spotted thistle, burdock, pumpkin;
• for brittle hair: avocado, jojoba, hemp, sesame, mango, burdock, safflower;
• in the presence of split ends of the hair: avocado, jojoba, poppy, carrot, burdock, safflower.

Watch the video on how to make essential oils at home:

Emulsion, cream, hydrolat and fruit powder

Emulsion and cream- dispersed systems consisting of two immiscible (or limitedly miscible) liquids, one of which is dispersed in the other in the form of small droplets - water in oil or oil in water. The droplet radius is small (1–50 nm). In industrial conditions, they are prepared using dispersants and homogenizers.

At home, it is possible to prepare emulsions and creams using mixers. For small volumes, cosmetic mini-mixers are commercially available, mixers for whipping coffee foam in thick creams do not work well.

Hydrosols - originally these were essential waters formed during the steam distillation of essential oil crops. Then other plants began to be distilled, in which there is a very small amount of essential oil or it is completely absent, but the plant itself has medicinal properties. The yield of hydrolate from 1 kg of plant material is from 1 to 5 liters. They are stored in a dark place, preferably in a dark container, at a temperature below 10ᵒС. Shelf life - up to 1 year, however, many deteriorate earlier. To preserve water, manufacturers use alcohol from 1 to 30% and other preservatives. It is very good to use waters preserved with alcohol in medicinal preparations, but for cosmetic purposes it is necessary to choose hydrolats without preservatives.

Hydrolates can be prepared at home by steam extraction.

fruit powder- homogeneous powder. Has a natural color, smell and retains the composition useful substances ripe fruits and berries. Produced by spray drying without exposure to high temperatures. Commercially made fruit powders dissolve easily in water. Used as gentle scrubs, added to various masks for the face and body, in creams, ubtans, you can take baths with them.

There are different ways to extract essential oils from plants. These are distillation, pressing, extraction with solvents, and the most rare because of the high cost - enfleurage. Each method has its own advantages and disadvantages. And essential oils obtained in different ways have different properties.
For the production of essential oils and absolutes for CA IRIS, only distillation, pressing and enfleurage methods are used.

Method 1 - Distillation (steam distillation)
"... sometimes, when rosemary, sage, mint or anise seeds could be bought cheaply on the market, or when rather large quantities of toffee tubers, ... cumin, nutmeg, or dried carnation flowers, the excitement of the alchemist woke up in Baldini, and he pulled out his large copper alembic with a condenser ladle mounted on it. He called it "the head of the Moor" and was proud that forty years ago, on the southern slopes of Liguria and the heights of the Luberon, he distilled lavender with it in an open field. And while Grenouille was crushing the goods destined for distillation, Baldini, in a feverish rush, for the speed of processing is the alpha and omega of this business, made a fire in a stone oven, where he put a copper cauldron with a fairly large amount of water. He threw the plants chopped into pieces there, put a double-walled cover on the branch pipe - the "Moor's head" - and connected two small hoses for outflowing and inflowing water. Then he fanned the fire.
The contents of the cube gradually began to boil. And after some time, first in oscillating drops, then in a filamentous stream, the distillate flowed from the third pipe of the "Moor's head" into the Florentine flask, substituted by Baldini. At first, it looked very unattractive, like a thin, cloudy soup. But gradually, especially after the filled flask was replaced with a new one and calmly set aside, this thick was divided into two different liquids: flower or herbal water settled below, and a thick layer of oil floated on top. Now all that remained was to carefully, through the lower neck of the Florentine flask, drain the gently fragrant flower water and get in the remainder pure oil, essence, strongly smelling essence of the plant.
Grenouille was delighted with this process. ... After all, the fragrant soul, the essential oil, was the best thing about them, the only thing that interested him in them.
This is the most common method for isolating essential oils. Aromatic components are extracted from vegetable raw materials due to the properties of steam, and sometimes also due to high blood pressure. Plant material is placed on a grid with boiling water; or heated steam from some other source is passed through it. Passing through the raw material, the steam carries away the volatile components. It is then cooled in a coil and condensed as a mixture of distilled water and oil. This mixture is collected in a special receiver, shaped like hourglass. In most cases, distilled water is heavier than oil and settles to the bottom, while the essential oil collects at the top of the receiver. Then you can open the tap and drain the oil.
Proper oil distillation (steam distillation) occurs at a temperature of 360 degrees for 8 hours at a pressure of 2 atmospheres. This technology is used in the manufacture of essential oils for CA Iris. The advantage of such a “slower” distillation is that it allows you to gently remove larger molecules from the oil, and the range of odors in the product at the output is richer, and the curative polyterpene fraction is preserved.
AT modern methods distillation, higher temperatures can be used, so that the essential oil is extracted quickly, sometimes in just a few minutes. This is a fast, cheap and efficient method of production, however, the "bouquet" (that is, the range of smells) of the essential oil obtained in this way is not so diverse, and some medicinal properties are lost with this method of distillation.

2 way - spin
Squeezing (pressing) is a method of obtaining essential oils from the peel of citrus fruits (orange, lemon, tangerine, etc.). The oil is released under the action of a press, without heating.
The essential glands of citrus plants are easy to see even with the naked eye - these are round cavities on the peel filled with essential oil. When squeezing the peel, the oil is easily released. In ancient times, citrus essential oils were pressed by hand, and today the oil is extracted under the influence of a press.
After pressing, the resulting essential oil contains cake particles and mucus, which are removed by settling or centrifugation.
Cake is a mass that may contain the rest of the essential oil, not squeezed out with a press (up to 30%, depending on the quality of the equipment). Usually cake is subjected to secondary processing - distillation, to obtain the rest of the oil. The oil obtained in this case is worse in quality than pressed essential oil, but it is not phototoxic in contrast to it. It can be used as a fragrance food products and household chemicals.
Oils obtained by pressing contain phototoxic substances - furocoumarins. Such oil, when it comes into contact with the skin, increases its sensitivity to solar radiation, causing local hyperpigmentation and burns. To prevent these phenomena, phototoxins are chemically removed from the oil. And for oils with furocoumarins, a recommendation is usually given - do not apply before going out in the sun.
3 way - Enfleurage
It seemed that on the fatty plates, as in a mirror, the sweetly persistent erotic aroma of jasmine was captured and reflected quite naturally ... For Grenouille's scent, of course, still revealed the difference between the smell of flowers and their preserved aroma: like a thin veil, its own smell of fat lay on it ( arbitrarily pure), smoothing the aromatic image of the original, moderating its piercing, perhaps even making its beauty bearable for ordinary people ... In any case, the cold enfleurage was the most sophisticated and effective means capturing delicate odors.
There was no better.
Patrick Suskind. Perfumer.
Enfleurage is a method of extracting aromatic substances from plants with a low content of essential oils. The method was popular in France in the 19th century, and is now almost never used due to the technical complexity.
Jasmine, tuberose, centifolia rose, violet, mimosa, orange and cassia flowers were used as raw materials for the enfleurage.
There are two types of enfleurage: cold and hot. The first one is more widespread.
cold enfleurage
Purified animal fat (beef or pork) was smeared on the glass, enclosed in a wooden frame. Fresh flowers or petals were superimposed on top of the layer of fat. The frames were stacked on top of each other to keep the fat from being absorbed. foreign odors, and raw materials from evaporation. The fat absorbed fragrant components within 1-3 days, after which the flowers were removed and replaced with fresh ones.
This continued until the fat absorbed the required amount of volatile substances (1 kg of fat can absorb the aroma of 3 kg of flowers). At this stage, the fat received the name "flower lipstick" and was removed from the glass with a spatula. Lipstick was given a name, depending on how many times the raw material was changed - for example, the raw material was changed 27 times and such lipstick was called "Lipstick No. 27".
Next, the lipstick was mixed with ethyl alcohol in order for the aromatic components to dissolve in alcohol. For the best dissolution, lipstick with alcohol was placed in a “thresher”, where alcohol and fat were intensively mixed.
Next, the lipstick was separated from the alcohol by filtration.
Final stage enfleurage - vacuum distillation at low temperatures to remove alcohol. The result was fragrant absolute oil (Essence absolue d'enfleurage) - the most valuable product for perfumery!
And lipstick, which contained the remains of aromatic substances, was usually used further for the manufacture of soap.
hot enfleurage
This method was familiar to the ancient Egyptians, but found its way to Grasse, France. Fat was melted in cauldrons, flowers were added there, which were regularly mixed under constant heating (up to about 60 degrees) for 2 hours. The next day, the flowers were lifted from the cauldron with a sieve and replaced with fresh ones. The procedure was repeated at least 10 times. When the fat could no longer absorb the fragrance, it was filtered out from the flowers (this fat was also called lipstick). Further fragrant oil It turned out in the same way as with cold enfleurage.
The enfleurage method requires a large number labor force (layout of flowers, replacement of raw materials, equipment control, etc.). What causes the high cost of the absolute. To obtain the CA IRIS absolute, the method of cold enfleurage is used. which also improves the quality and component composition oils, as overheating can destroy some heat-sensitive components.
Since 1930, most perfumers abandoned this technique due to the high cost of the resulting oil. But for professional aromatherapy, that price is justified by the result. The method, which we will discuss below, will confirm that new technologies are not always better than old ones.
Method 4 - solvent extraction
Solvent extraction is used in cases where the plant raw material yields too little essential oil during distillation (for example, jasmine, narcissus, lotus, etc.) or when distillation produces an oil of unsuitable quality (high temperatures during steam distillation can distort the aroma and promote the formation of products decay). This technique is an alternative to the enfleurage and distillation method, which requires temperature regime and a certain time. In a word, this is the least energy-consuming way to obtain essential oils, since it does not require heating, pressure, or mechanical pressing.
For this method, highly purified volatile organic solvents are used: petroleum ether, hexane, pentane, diethyl ether.
Solvents are subject to certain requirements. The solvent must be odorless and not form toxic substances or substances that change the smell of the product (for example, ethyl alcohol forms esters with various components of plant materials, thereby distorting the smell of the finished product). The lower the boiling point of the solvent, the better - this is explained by the fact that with an increase in the temperature of the extraction process, the risk of the formation of undesirable decomposition products increases. These requirements are met by petroleum and diethyl ethers, so they are most commonly used in extraction.
The flowers are filled with a solvent, after which the solvent is removed by vacuum drying. A very thick, sticky residue remains, which can be dissolved in alcohol. The alcohol is then drawn off and an extract is obtained. This method is preferred by perfumers. Perfumers claim that the aroma of the extract is closer to the original smell of flowers than the smells of oils obtained in any other way. However, aromatherapists know that this oil always contains some petroleum solvent, which is dangerous for the immune system and can cause allergic reactions. Oils obtained in this way should not be taken orally!