Essential oils.
DEPARTMENT OF CHEMICAL TECHNOLOGY OF WOOD
Profile of the Department:
nanobiotechnology
In the world knows about 2500 species of fragrant plants, of which more than 40% grow in the tropics. Industrial importance are about 200 species. Others are not used, because or contain a few essential oils, or are uninteresting composition of oil.
Essential oils (EM) plant organs are distributed unevenly. For example, in the Rose of EM is in the flowers, the geranium - the leaves of mint and basil - in the leaves and inflorescences, in Laurel, and eucalyptus - in the leaves and young branches.
The contents of EM in the plant material varies from 0,04% (acacia flowers, and lily of the valley) to 22% (clove buds).
EM Unlike fatty oils evaporate and leave no stains on the paper.
Fragrance dignity of EM due to content and the ratio of major components. Qualitative EM should not contain components with an unpleasant odor or burning taste. These include: a pink oil - low molecular weight organic acids, in lavender oil - camphor, a geranium and mint - Menton.
During the processing of aromatic raw materials extraction method with HEM extracted waxes - esters of higher acids (C16 ... C30) and alcohols. The wax contains, and higher alcohols in the free form (C11 ... C31).
For the extraction of the substance receives 2:
1 - concrete (extract), which consists of the EM and waxes
2 - Absolute Oil (absolutes) - part concrete, soluble in ethanol. Insoluble absolutes - wax.
Aromatic materials is divided into 5 groups:
1. Grain (fruit, seeds): coriander, anise, caraway, dill.
2. Herbaceous (leaves, above-ground parts of herbaceous plants, the young branches of trees and shrubs): mint, geranium, eucalyptus, laurel, tarragon, dill, tobacco, anise, pine needles).
3. Flower: (flowers, inflorescences, flower buds): rose, sage, lavender, jasmine, tobacco, lily, lilac, iris).
4. Root (roots, rhizomes): sweet flag, iris.
5. Fixings: oak moss, ladannik.
EM in plants is in free or bound form. In the latter case, the plant has no smell, because glycosides EM does not smell. This is HEM isolated by hydrolysis.
Solvents, oils
1. Petroleum ether. Applied fraction, boiling within 36 ... 70 ° C. In petroleum ether for perfume should not contain sulfur compounds.
2. Liquid carbon dioxide. Very promising solvent, because Extraction is carried out at room temperature, without destroying the biologically active substances (BAS). Extraction of liquid carbon dioxide is conducted under pressure 54 ... 59 atm. Carbon dioxide provides a well-soluble substance, but almost does not extract water-soluble substances.
The main methods for extracting and processing of essential oils
Steam distillation
Extraction of volatile rastvoritelchmi
Extraction of non-volatile solvents (maceration)
Sorption (anflerazh)
Mechanical selection (pressing)
The method chosen should ensure the highest yield and quality.
Steam distillation
This is the most common method of obtaining the EM.
Extraction of volatile solvents
With this method, the extract yield is always higher than the distillation with steam, as except EM extracted resinous substances and waxes. The mixture of EM, tar and waxes is specific.
More concrete is treated with ethyl alcohol and get the absolute oil.
Extraction of non-volatile solvents (maceration)
This ancient method of processing raw flower. The solvent used high-quality animal fats (beef, pork or a mixture - case) or vegetable oils.
The essence of maceration is based on extracting aromatic substances by infusion, and their subsequent separation from the fat mixture by extraction with ethyl alcohol.
In the heated solvent is downloaded flowers and withstand up to two days. Then otfugovyvayut solvent, which is immediately used for the next defense of the fresh raw materials. Changing colors is made up of twenty-five times. At the end of the process of intense fragrances solvent dried with anhydrous sodium sulfate and filtered.
Product using animal fats called lipstick, using plant material - the fragrant oil. These products are used directly in cosmetics and perfumes - in perfume compositions.
In most cases, lipstick and perfumes treated with ethyl alcohol and get flower extract. Floral extracts released under the numbers which express the quantity in kilograms of raw materials consumed in the preparation of ten liters of the extract.
Sorption method (anflerazh)
Used for those commodities in which the processes of oil is not terminated after harvest (jasmine, tuberose, lily, lily).
As the sorbent is most often used shell, from which the lipstick, from which the absolute oil. When anflerazhe apply special wooden frame (chassis) with stuck in the middle of thick glass. On the glass is applied a thin layer of shell, between the chassis is put a layer of material is not above the height of the board. The chassis are placed in a battery of thirty - forty pieces.
If you use vegetable oil instead of the glass insert, metal mesh, which reinforce the bulk pieces of loose tissue, soaked in oil.
Mechanical method (pressing)
Used for processing of citrus fruit (orange, lemon, mandarin, grapefruit, bergamot). They EM is in large, easily accessible storage places located in the superficial tissues of the skin. In the composition of citrus oils, a lot of terpene hydrocarbons, which limit their solubility in alcohol. Therefore EM citrus sent to deterpenizatsiyu (exemption from terpene hydrocarbons), which is carried out by vacuum distillation.
In modern lines simultaneously receive juice, pulp and EM.
