Vegetable oil is one of the most high-calorie foods (850-900 kcal per 100 g). It is a source of vitamin E (tocopherol) and essential fatty acids for the human body, does not contain cholesterol, unlike animal fats.

The quality of vegetable oil is standardized by a standard for a number of indicators. Organoleptic characteristics: transparency, color, smell and taste. Refined (purified) oil should be completely transparent, without sediment, light yellow in color. In unrefined sunflower oil of the highest and first grades, a light "mesh" over the sediment is allowed, and in the second grade - slight turbidity. Smell and taste should be characteristic of fresh oil without foreign smell, aftertaste and bitterness. Deodorized oil should be odorless. In the second grade sunflower oil, a slightly musty smell and a slight bitterness are allowed.

Methods for obtaining vegetable oil

Oil from oilseeds is extracted in two main ways:

mechanical, which is based on pressing crushed raw materials; used in oil mills or churns of agricultural enterprises; a by-product is cake, in which a significant amount of oil remains (8-10%);

chemical (extraction), in which specially prepared oilseed raw materials are treated with organic solvents; used in oil extraction plants; allows you to release oil in large quantities, since no more than 1-3% of oil remains in the waste, called meal.

Extraction of oil by pressing.

The mechanical method of obtaining oil by pressing the oil-bearing material, which has undergone preliminary preparation, is widespread almost everywhere not only at press oil plants, but also at oil extraction plants, where the main technological scheme is prepressing - extraction.

Only a continuous pressing method is used on screw presses. A distinction is made between screw presses for preliminary oil removal (forpress) and for final oil removal (expellers). The initial pulp is a free-flowing porous material. With all-round compression under the influence of the applied pressure, two closely related processes take place: separation of the liquid part - oil; connection (fusion) of solid particles of the material with the formation of a briquette - cake. Screw presses have the same type of working bodies and the general scheme of the device and work. The main working bodies of the screw press are the screw shaft and the grain cylinder. The end products of the pressing process are press oil and cake. When the auger shaft rotates, placed in a zeerny cylinder, that is, in a drum assembled from strips with small gaps between them, the material is transported from the loading point to the outlet and is compressed. At the same time, pressure arises in it, which squeezes the oil out of the pulp. The oil flows through the gaps in the bore cylinder and collects in the sump. The squeezed oil material (cake) at the exit from the grain cylinder meets with a device that regulates its thickness at the exit from the press.

Cold pressing only means that before pressing, a special moisture-thermal treatment of the crushed raw material is carried out in milder conditions or not at all. The resulting oil retains its natural qualities: color, smell, taste, consistency, while the content of unsaturated fatty acids and vitamins remains unchanged - Cold pressing as a method for the production of vegetable oils is most often used to obtain special-purpose oils from specific raw materials, for example, fruit seed oils (apricot, peach, etc.), pine nut kernels, etc.

Prepressing - extraction is used for the final extraction of oil from the prepress shell (cake). Solvents used for the extraction of vegetable oils by the extraction method must meet the requirements imposed on them by the technique and technology of the extraction process. In general, these requirements are determined by the desire to obtain the highest oil yield during extraction, to ensure the best quality indicators of the finished product - oil and meal, to avoid the harmful effects of the solvent on the human body and to ensure the safety of working with it. In the practice of extracting vegetable oils, the most widespread are aliphatic hydrocarbons, in particular, extraction gasolines, hexane, and nefras. The cake is preliminarily processed, the purpose of which is to create an optimal structure for the extraction of oil with a solvent, for which it is crushed on crushers (hammer and disk), conditioned in vat braziers, and petalled on crusher roller machines. The shape of the material particles in the form of a petal (a plate of material with a thickness of about 0.4 mm) makes it possible to have a mass of material that is easily permeable to a solvent in the extractors. From under the crimping rollers, conveyors send the petal to the extractor - the main apparatus of the extraction shop, designed to extract oil into the solvent during countercurrent contact. Gasoline with a boiling point of 65 ... 68 ° C is used as an extraction solvent.

In continuously operating auger extractors, a counterflow of petals and a solvent heated to a temperature of 50 ... 55 ° C is created. The resulting solution is called miscella, which, after extraction, is filtered on special filters and poured into miscella collectors. To separate the oil from the solvent, the miscella is sent first to the preliminary and then to the final distiller, where it is treated with hot steam using a vacuum until the solvent is completely removed. The filtered solid part in this case is called meal. After the extraction, the meal contains about 1% oil and 40% solvent, it is treated with live steam using a vacuum to evaporate (distill off) the solvent, dried, cooled and ground.

Direct extraction of raw mint is used mainly in the processing of low-oil raw materials: soybeans, coriander waste. Extraction of oil-bearing material is carried out without preliminary removal of oil. It consists only in moisture-heat treatment, followed by crushing to obtain a petal, which is sent to the extractor.

Purification of vegetable oils

Purification of crude oils from various impurities is called refining, and oils that have not undergone any processing after receipt, except for filtration, are called crude. They contain a variety of impurities, including unwanted and even harmful ones. Impurities include substances of various nature and origin. However, in addition to undesirable or harmful impurities in fats, there are always accompanying substances that are not only useful, but also necessary for the normal functioning of the human body. Such substances include, for example, fat-soluble vitamins (K, E), carotenoids, sterols, etc.

Refined fats are easier to spoil, since natural antioxidants (phospholipids, tocopherols) are removed from them during refining. Therefore, they strive to conduct the refining process in such a way that, while extracting undesirable impurities, it is possible to preserve beneficial features... For the same purpose, the depth of oil refining is limited. Depending on the origin of impurities, on the state in which they are in the fat (in the form of a coarse suspension, colloidal-dissolved state or in the state of a true solution), and also depending on the purpose of the oil, they are used different methods refining.

The sequence of refining processes and the types of oils obtained

In accordance with the mechanism of the processes, refining methods are conventionally divided into physical, chemical and physicochemical.

Physical methods... These include settling, filtration, centrifugation. With the help of these methods mechanical impurities and partially colloidal-dissolved substances, for example, precipitated phospholipids, water that got into the oil during the extraction process, are removed from oils.

Mechanical impurities(particles of husk, cake) not only worsen the presentation of the oil, but also cause enzymatic, hydrolytic and oxidative processes. All these processes impair the organoleptic characteristics and physiological value of oils. Therefore, mechanical impurities are removed immediately after obtaining oils.

Chemical methods. These include alkaline refining or neutralization. Neutralization - treatment of oil with alkali to remove excess fatty acids. In the process of neutralization, soaps are formed - salts as a result of the interaction of fatty acids and alkali. Soaps are insoluble in neutral fat and form a sediment - soap stock. For alkaline refining at industrial enterprises, NaOH solutions of various concentrations, Na 2 C0 3 solutions, and sometimes KOH are used.

Physicochemical methods... Using these methods, impurities that form true solutions in oils are removed from oils, without chemical changes in the substances themselves (coloring, flavoring and odorizing substances, etc.)

Hydration of phospholipids- oil treatment with water when heated to release phospholipids, protein and mucous substances, mechanical impurities. As a result of hydration, phospholipids and other impurities lose their solubility in oil and precipitate, which is filtered off.

Freezing sunflower oil is subjected to the removal of waxy substances. The presence of waxes in the oil impairs its presentation. To isolate waxes, the oil is subjected to a special treatment before or after alkaline refining. First, the oil is cooled ("frozen") to 10 ... 12 ° C and kept at this temperature, stirring slowly, until the formation of wax crystals. Then the oil is filtered from the wax crystals. The filtered oil is transparent, does not become cloudy when cooled, even to 5 ° C.

Whitening oil- the process of extracting coloring substances from oil by treating it with adsorbents. With a variety of bleaching clays, which are called bleaching earths or bleaching powders, and Activated carbon... The bleaching process consists in the fact that the oil is mixed with an adsorbent for some time in special apparatus, and then filtered. In this case, the bleaching powder remains on the filter together with the adsorbed dyes, and the clarified oil passes through the filter. This oil is used for the production of margarine, mayonnaise, confectionery fat, etc.

Deodorization of oil is the process of stripping off volatile substances that give the oil smell and taste. Deodorization is carried out with the aim of obtaining "impersonal" (almost completely devoid of characteristic for this type of smell and taste) oils, as well as extracting extraneous tastes and odors from oils. Deodorization is based on the difference in the temperatures of evaporation of volatile aromatic substances and the fats themselves (triacylglycerols). Vegetable oil is placed in special devices - deodorizers and at high temperatures (210 ... 230 ° C) under vacuum, volatile substances are distilled off, which give the oil a smell and taste. Deodorization is the most reliable way to remove pesticides from oils, since under these conditions they are completely destroyed.

Oil technology

The oil and fat industry is one of the most complex branches of the food industry. It includes oil extraction plants that produce vegetable oils and fats from oilseeds; hydrogenation plants that convert liquid oils into hydrogenated solid oils (fatty oils); workshops for transesterification of oils and fats; margarine factories producing margarine, butter spreads, mayonnaise and cooking fats; soap factories producing toilet and laundry soaps, glycerin and fatty acids; factories for the production of food surfactants (surfactants) and synthetic detergents.

Main raw materials: oilseeds, fruit pulp of some plants (olives), secondary products (corn germ, stone fruit, etc.). Seeds are divided into high oil> 30% fat (sunflower, rapeseed, peanuts), medium oil 20-30% fat (flax, cotton), low oil< 30 % (соя). масло маргарин рафинация

Obtaining vegetable oils

Vegetable oil production includes preparing seeds for storage and storing seeds; preparatory operations related to the preparation of seeds for oil extraction; oil pressing and extraction, primary and complex oil purification, meal processing.

A specific feature of the preparation of sunflower seeds for processing is their separation by size, as a rule, into coarse and fine fractions, processed separately according to various technological schemes.

Currently, two methods are used to extract oil from seeds: sequential oil extraction when processing seeds with a high oil content - first by pressing, in which about 3/4 of the total oil is obtained, and then by extraction, with the help of which the rest of the oil is extracted, and single extraction of oil from low-oil seeds by extraction method - direct extraction method.

In addition to the methods of pre-pressing and subsequent extraction and direct extraction, used in large oil and fat enterprises, in recent years, small installations on which only one oil extraction (final) is carried out has become widespread. The press is the main and often the only technological equipment of the mini-plant. Pressing oil from uncrushed, non-crushed seeds, without any preliminary heat or water-heat treatment, allows you to extract from oilseeds only a part of the oil contained in it.

1. Preparation for storage and storage of seeds. The harvesting period for most types of oilseeds lasts 2 ... 3 months. The seeds of most oilseeds are stored with a moisture content that exceeds the optimal values ​​for storage and technological processing. The stored seeds breathe, this leads to the consumption of nutrients, therefore, during storage, the oil content of the seeds decreases, the content of free fatty acids and their oxidation products increases in the oil.

With a decrease in temperature, the intensity of respiration decreases. Cooling seeds to low plus or small minus temperatures by blowing cold air through the seed mass has a beneficial effect on their quality even when storing seeds with moisture above critical.

One of the promising ways of storing wet seeds is storage in controlled gas environments containing oxygen (1 ... 2%) and nitrogen (98 ... 99%). The almost complete absence of oxygen inhibits the respiration of the seed mass, as a result of which the quality of the seeds can be preserved.

When preparing oil seeds for storage, it is necessary to reduce their moisture content to a level below the critical one. The most common method of reducing the moisture content of seeds before storage is heat drying, during which the seeds are heated using a drying agent (usually a mixture of air and flue gases). The dried seeds are then cooled by blowing atmospheric air through them.

2. Hulling of seeds. When processing many oil seeds and fruits, the fruit and seed coats are separated from the main oil-containing tissues - the kernels.

The separation of the shells from the kernel consists of the operation of destroying the integumentary tissues of the seeds - crumbling and subsequent separation (winnowing) of the resulting mixture - rushanka into a kernel and husk (husk). The destruction of the shell should not be accompanied by crushing or destruction of the core. Methods of collapse by blow, friction, cutting.

The quality of the seed collapse (the quality of the rushanka) is characterized by the content of undesirable fractions in it - whole seeds and partially destroyed ones, the so-called whole or undercutting, crushed kernels (chaff) and oil dust. The presence of whole and partially destroyed seeds increases the husk content of the kernel, the presence of chaff and oil dust increases the loss of oil with the separated husk.

3. Grinding seeds. To extract oil from seeds, it is necessary to destroy the cellular structure of their tissues. The end result of the grinding operation is the conversion of the oil contained in the seed cells into a form available for further processing. The required degree of grinding is achieved by applying mechanical forces to the processed material, producing crushing, splitting, abrasive or impact actions. Grinding is usually achieved by a combination of several types of these forces.

The material obtained after crushing the seeds is called mint.

Well-crushed mint should consist of particles of uniform size passing through a sieve with holes 1 mm in diameter, should not contain intact, intact cells, and at the same time, the content of very small (mealy) particles in it should be low.

To obtain mint, roller machines are used. The working bodies of the machine are five rolls located one above the other; the upper roll is corrugated, the rest are smooth. All rolls are fixed to the bed.

4. Water-heat treatment of mint. Oil adsorbed as thin films on the surface of the mint particles are retained by surface forces. For effective oil extraction, the mint hydrothermal treatment is used. With moistening and subsequent heat treatment of the mint, the bond of lipids with the non-lipid part of the seeds - proteins and carbohydrates - weakens, and the oil passes into a relatively free state. Then the mint is heated to higher temperatures, the viscosity of the oil decreases markedly, at the same time the moisture content in the mint decreases, and a partial denaturation of proteins occurs, which changes the plastic properties of the mint. The mint turns into pulp.

In a production environment, the preparation of the pulp consists of two stages. The first one - moistening the mint and initial heating - is carried out in inactivators or steaming-humidifying screws. Intensive short-term heating of the mint to a temperature of 80 ... 85 ° C with simultaneous moistening up to 8 ... 9% (for sunflower seeds, flax) contributes to the uniform distribution of moisture in the mint and partial inactivation of hydrolytic and oxidative enzymes of the seeds, which degrade the quality of the oil. The second stage - heating the mint to 105 ° C and drying it to the final moisture content (5 ... 6%) - is carried out in braziers. Fryers for cooking pulp are divided by design into vats, drum and screw.

• 5. Oil extraction by pressing. The oil is squeezed out in screw presses of various designs. Pre-pressing is carried out using a forepress, and the final pressing is carried out with an expeller. During pressing, the pressure is increased gradually, because with a sharp increase in pressure, the pores are pressed in, and the output of oil is reduced. In order to increase the oil yield during the pressing process, the temperature of the processed material is increased, preventing it from overheating. When overheated, undesirable processes occur: oil oxidation and the transition of protein substances into oil. It is impossible to achieve complete degreasing of the pulp using the pressing method, since thin layers of oil always remain on the surface of the cake leaving the press, held by surface forces many times higher than the pressure developed modern press... On presses developing maximum pressure and working with maximum oil removal, cake with oil content of 4 ... 7% is obtained. On presses of preliminary pressing - forpress, the most widely used in industry, cake with oil content of 15 ... 17% is obtained.
• 6. Oil extraction by extraction. Provides almost complete oil recovery.

Before extraction, the prepress cake is structured, giving it the structure of crumbs, granules or petals, which ensures maximum oil extraction by the solvent.

As solvents for the extraction of vegetable oils, extraction gasoline with a boiling point of 63 ... 75 ° C and an oil solvent (nefras) with a boiling point (65 ... 75 ° C) are used.

As a result of the extraction, a solution of oil in a solvent (miscela) and a fat-free material (meal) are formed.

The extraction of vegetable oils is most often carried out by the method of immersing the extracted material in a countercurrently moving solvent under conditions of absolute counterflow or by the method of multi-stage irrigation of the material with a solvent under conditions of relative counterflow, when only the solvent moves, and the extracted material remains at rest on a moving belt, in a moving bucket, section of the rotor and others. Advantages of extraction by immersion: high extraction rate, short duration of the process, simplicity of the design of the extraction apparatus and high utilization of its geometric volume (up to 95%). The latter excludes the possibility of the formation of an explosive mixture of air and solvent vapors in the extractor. The disadvantages of this type of extractors include a low concentration of the final miscella (15 ... 20%), a high content of impurities in the miscella, and large dimensions of the extractor in height.

Advantages of multi-stage irrigation extraction: obtaining pure, highly concentrated miscella (35 ... 40%); disadvantages: a longer extraction process, a low utilization factor of the geometric volume of the extractor (45%) and the possibility of the formation of explosive mixtures of solvent vapors and air inside the apparatus, a complex design of the extractor.

To clean the miscella from solid impurities, sedimentation tanks, hydrocyclones and fabric filters are used. If the content of impurities in the miscella is low, then the miscella is purified by passing it through an electrolyte solution (5% NaCl solution).

Distillation of miscella. Miscella consists of a low-boiling solvent and a practically non-volatile oil. At low concentrations of oil in miscella, the solvent is evaporated under normal conditions. As the concentration of oil in the miscella increases, its boiling point rises very quickly. To reduce the distillation temperature and accelerate the process, solvent distillation under vacuum, as well as with water vapor, is used. Distinguish between spray distillation, film distillation - in falling and rising film and layer distillation.

In industrial installations, the distillation of miscella is carried out in a two- and three-stage scheme. The installation for three-stage distillation consists of two film distillers (first and second distillation stages) operating in series at atmospheric pressure (temperature 80-90 ° C, oil concentration 75-80%), and the final one operating under vacuum (residual pressure 0.04. .0.06 MPa, temperature 110-120 єС).

The quality of the oil during the distillation of miscella depends both on the technological parameters of the process - the final temperature of the oil and the duration of the processing of the miscella, and on the content and composition of lipids extracted from the extracted material - phospholipids, carotenoids and other fat-soluble pigments, vitamins and provitamins, and also products of lipid oxidation, etc. The thermal effect on these groups of lipids leads to their change and not only reduces the quality of the oil, but also significantly complicates the distillation of miscella. Of particular importance is the problem of removing before distillation the fat-soluble pigment of cotton seeds - gossypol, which, when heated, undergoes various chemical transformations and forms products that are difficult to remove from oil. To remove gossypol, the miscella is subjected to alkaline refining before distillation.

7. Refining oils and fats. The process of oil purification from unwanted lipid groups and impurities is called refining, the ultimate goal of which is the extraction of triacylglycerides from natural oils and fats, free from other lipid groups and impurities. Refining is not always carried out until all structural lipids and impurities are completely removed, with the exception of mechanical impurities and water, the removal of which is mandatory already during the primary oil refining.

Purification methods: physical (filtration, sedimentation, centrifugation), chemical (hydration, acid and alkaline refining), physicochemical (distillation, deodorization, adsorption).

Removal of suspended solids and water from the oil is carried out by settling in sedimentation tanks, mechanical dry traps, using sedimentation centrifuges and by filtering through cloth on frame filter presses.

Full refining is carried out when obtaining salad oil used for direct consumption, for oils and fats used in the production of margarine, confectionery, cooking fats and mayonnaise.

Rice.

Hydration is the removal of a group of substances with hydrophilic properties from the oil using water, the most important of which are phospholipids. Phospholipids are nutritionally valuable compounds with antioxidant properties. During storage of oils, they fall out in the form of a readily decomposing sediment, which complicates a number of technological operations for processing oil. Therefore, phospholipids are isolated from oil by hydration, and then used as an independent product for food, feed and medicinal purposes.

The hydration process consists in mixing the heated oil with a metered amount of water or other hydrating reagents (aqueous solutions of NaCl and surfactants). In this case, phospholipids form hydrophilic particles with water, lose their ability to dissolve in fat and precipitate (hydration fus). Optimum temperature for hydration of oils: sunflower - 45 ... 50 ° С, soybean - 65 ... 70 ° С; the amount of water added to the oil is also different: for sunflower oil 0.5 ... 3.0% by weight of oil, for soybean oil - up to 6%.

Freezing (winterization) is the removal of waxes and wax-like substances from the oil. The essence of the process lies in the slow cooling of the oil to 10 ... 12 єС with weak stirring in the exporter - a cylindrical apparatus equipped with a frame stirrer. The oil is kept in the display for 4 ... 6 hours. Here, the waxes dissolved in the oil crystallize. Then the oil is heated to 16 ... 18 ° C to reduce its viscosity and filtered on frame filter presses. To speed up the process, auxiliary powders (diatomaceous earth, perlite, etc.) are applied to the filtering surface, which improve the drainage properties of the sediment.

Neutralization of oils with alkali is based on the treatment of refined oil with aqueous solutions of NaOH, during which free fatty acids interact with alkali to form aqueous solutions of soap - soap stocks.

Soap stocks are insoluble in oil and, since their relative density is higher than that of oil, they form sediments, which are then separated from the oil in separators.

The neutralization temperature is 85 ... 90 ° C, the alkali concentration is from 70 to 150 g / l and the excess of alkali from the theoretical amount is 5 ... 20%, depending on the acid number of the oil supplied for neutralization.

Oil refining (neutralization) in miscella is efficiently carried out at an optimal miscella concentration of 35-45%. The miscella leaving the extractor with a lower concentration is either first evaporated in the first distillation stage, or a pre-pressed oil obtained from the same seeds is added to the miscella. Miscella of optimal concentration (35-45%) at a temperature of 20-22 ° C enters the jet mixer, where it is mixed with alkali. A mixture of miscella, soap flakes formed by the interaction of alkali with free fatty acids of oil, phospholipids, gossypol and other substances is heated to 60-70 ° C and treated with demineralized water at a temperature of 90-95 ° C in continuous settling tanks, while separating from the oil water-soluble soap stock. From here, the purified miscella enters the second stage distillers. Distillation of solvent from soap stock is carried out in a column. The column is operated under vacuum. The soap stock heated to 110 ° С with solvent is discharged through the nozzles into the steam space of the column, the solvent evaporates, and the soap stock goes to the warehouse.

Distilling off the solvent from the meal. The meal leaving the extractor contains from 20 to 30% of the solvent, which is removed by heating in vat evaporators (toasters).

The solvent removed during the processing of miscella and meal is recovered by condensation from steam-gas mixtures in heat exchangers-condensers, and then returned to production.

The meal intended for use as animal feed is subjected to granulation, pre-mixing it with a hydrofuse - a mass precipitated when processing press and extraction oils with water, or with soap stock - a sediment that is obtained when processing miscella or vegetable oil with an alkali solution.

Obtaining protein isolates from meal. Protein is extracted from the meal first aqueous solution NaCl, then NaOH. The insoluble precipitate is separated, and the extract containing 2-3% protein is purified and precipitated with HCl. The precipitated protein is washed and dried in a spray dryer with air at a temperature of 180-200 ° C.

Ready protein with a moisture content of 3-8% is packaged and sent to consumers. The total protein yield is 20-25% by weight of the meal. The insoluble residue of the meal after drying is used for animal feed.

Oil bleaching (adsorption refining) - removal of fat-soluble pigments from oil - carotenoids, chlorophylls, and for cottonseed oil also gossypol and its derivatives are provided for vegetable oils (except sunflower) intended for hydrogenation and production of margarine products. To bleach oils, bleaching bentonite clays and activated carbon activated by acid and heat treatment are used. The main component of bentonite clays are aluminosilicates Al 2 O 3 and SiO 2, which include alkali and alkaline earth metals.

When bleaching in oil, undesirable processes occur: isomerization of fatty acids, which reduces the biological value of the oil; formation of fatty acids with conjugated double bonds, which leads to the activation of oxidative processes in the bleached oil during storage. To reduce oxidative processes in oil, the bleaching process is carried out under vacuum.

Deodorization of oils - removal of odorizing substances from oil - low molecular weight fatty acids, aldehydes, ketones and other volatile products that determine the smell and taste of the oil, as well as the release of unwanted foreign compounds from vegetable oils - polycyclic aromatic hydrocarbons, pesticides, toxic products - aflatoxins, etc. dr.

The boiling point of oil and aromatics is very different, therefore, deodorization is carried out by distillation under vacuum.

the main goal entrepreneurial activity- making a profit with a relatively small investment. The production of vegetable oils as a business idea is the best fit for a businessman who wants to start his own business in a demanded area.

Vegetable oil production as a business strategy

In Russia, about 50% of oil is produced in medium or even small (home) enterprises and factories. These statistics are due to the small costs of an entrepreneur in the early stages of running a vegetable oil business and a quick payback. Volumes can be limited only by the amount of initial raw materials that the firm is able to redeem.

How profitable is it today to invest your capital in the production of vegetable oil? What equipment will be needed at the initial stage of production and how much will it cost?

About vegetable oil production

Vegetable oil in our time, without exaggeration, can be attributed to essential products. Almost no dish can be prepared without consuming a sufficient amount of vegetable oil. But cooking is far from the only area that consumes vegetable oils. They are irreplaceable in production:

• canned food (from vegetables and fruit to fish and meat),
• soap,
• repair paints,
• medical preparations (creams, ointments),
• cosmetics (creams, lotions, powders, lipsticks).

Vegetable oil is called because it is made from leaves, seeds, nuts or fruits of various kinds of plants: olives, corn, sunflower or flax seeds, cedar or macadamia nuts. There is also animal fat obtained from the organs of any animal or fish: goat, goose, cow, bear, badger, fish, whale.

Depending on the raw material, vegetable oil is subdivided into:

• linseed,
• mustard,
• corn,
• olive,
• sunflower, etc.

Oil can be solid or liquid.

The varieties of vegetable oils depend on the raw materials from which they are made.

Based on the purification method, the following types of vegetable oils are distinguished, such as:

• unrefined (mechanically purified) have a characteristic natural smell and taste, as well as a light yellow tint;
• refined (mechanically purified, hydrated and neutralized) have the same characteristic natural smell and taste, but less pronounced color;
• refined deodorized (completely refined, odorless and tasteless).

The chemical and physical properties of the oil will depend on what type of cleaning has been chosen.

The appearance of the final product is also influenced by the degree of refining. There are 6 degrees in total: the higher the degree, the cleaner and, accordingly, lighter.

Sunflower - known source vegetable oils. The most popular sales market in Russia has always been and still is the production and sale of sunflower oil. It can be obtained by cold pressing or hot pressing. Hot pressing leaves the taste of raw materials (in this case fried sunflower seeds), and cold - more neutralizes such indicators.

Vegetable oil production process

Technology for the production of vegetable oil from sunflower seeds - a rather complex process, which is divided into several main stages:

1. Cleaning of raw materials (sunflower seeds) from impurities (husks, sand, earth, leaves, stems). A separator is used (cost up to 45 thousand rubles).
2. Winnowing to remove minor debris and dry seeds. Rushilno-winder equipment is used (up to 75 thousand rubles).
3. Cleaning from its own husk (black shell), further grinding to the state of an oily gruel. A roller machine is used (from 430 thousand rubles).
4. Heating in steam or fire braziers up to 1100 ° C. A fire (up to 83 thousand rubles) and steam (up to 350 thousand rubles) brazier are used.
5. Squeezing raw materials and separating the cake (oil cake) from the oily liquid. The cake is sent for re-pressing. A screw press is used (from 650 thousand rubles).
6. Primary filtration of oily liquid from cake residues. Specialized filtering equipment is used (about 95 thousand rubles).
7. At an additional stage, the composition can be subjected to several stages of filtration, as well as to make it refined, bleach and deodorize (remove odors). At the final stage of pressing, the actual oil and cake remain, which still contains about 10% oil from its entire mass. At further additional stages, the manufacturer seeks to extract the maximum possible residues of the oil composition from the cake.
8. Extraction (one more additional stage) is the soaking of the residues (cake) in solvents (acetone, gasoline, hexane), which makes it possible to obtain at least 7% oil from 10%. An extractor is used (from 520 thousand rubles). It is considered a less environmentally friendly, but more economical way of obtaining raw materials.
9. The finished product is poured into containers. A dispensing device is used (from 400 thousand rubles).

Brief diagram of vegetable oil production technology

Companies specializing in oilseed production can use only one of the methods (pressing or extraction) or alternatively use both.

The production of sunflower oil is a waste-free procedure, because the residues formed throughout the extraction can be reused for other purposes. After extraction, almost completely defatted cake (meal) and residual oil in solvents (miscella) remain. For example, the meal is staffed and sent to cattle and small livestock farms: where the pomace is added as a nutritional supplement to animal feed. And miscella becomes the basis for paints and varnishes (drying oils) for repair. In addition, the cake can be squeezed out again and get fuz - biofuel for boiler plants.

Is it necessary to refine the finished product? In general, after primary filtration (stage VI), the oil is ready for filling into packaging containers. However, such a product is called "raw", since it still contains unnecessary protein compounds, fatty acids, dyes, phospholipids and wax, therefore, to improve the quality of the final result, it is possible and even necessary to carry out secondary filtration or refining. There are the following refining methods:

• physical (centrifugation, settling),
• chemical (alkaline refining, hydration),
• physico-chemical (deodorization, bleaching).

Conditions for the production of vegetable oil

Sunflower oil production is a very profitable enterprise. At the same time, the niche is quite tightly occupied by already competitive manufacturers who have been able to stay afloat for several years. If a businessman still wants to invest in this kind of enterprise, then he should weigh all the pros and cons, so that his business does not become unprofitable even at the stage of formation.

Vegetable oil can be produced: in factories, mini-workshops, small oil mills and at home.

Manufacturer requirements

A future entrepreneur who associates himself with a sunflower oil business must meet certain requirements:

• have a legal status (best of all, the founder of an LLC and an agricultural producer, who receive tax advantages and benefits from the state),
• have experience in selling products for retail,
• have connections with suppliers and the sales market.

In the case when an entrepreneur does not yet meet these minimum conditions, it makes sense to start producing rare types of oil (coconut, avocado) and sell it to friends or to small stores.

Vegetable Oil Filtration Equipment

Requirements for the premises

The basic requirements for the premises depend on the volume of production. If a businessman wants to establish a serious production of oil from vegetable raw materials, he will need an appropriate room. It should be:

• with an area of ​​1500 sq m,
• divided into several sections (production, warehouse for storing imported raw materials, warehouse for storing finished products),
• equipped with communication networks (electricity, water supply, sewerage),
• safe (protected from spontaneous combustion, with fire extinguishing agents),
• comply with sanitation standards.

If oil is not produced on an industrial scale, but in an oil mill, then the premises can be rented with an area of ​​up to 150 sq. M.

For home spinning, it is permissible to use a room.

equipment requirements

Today, almost every production process is automated. The production of vegetable oil will not be an exception. In the subtitle describing the technologies for the production of vegetable oil from sunflower seeds, it was already described in more detail necessary equipment and its approximate cost for setting up large-scale production. Summing up, we can add that the whole process from the point of view of the hardware component will look like this:

1. Devices for production (from 2 million rubles).
2. Refining devices (from 2,100 thousand rubles).
3. Devices for packaging (from 2200 thousand rubles).

Thus, the cost of equipping a mini-shop for the production of a vegetable pressed product will amount to about 6,300 thousand rubles.

For an oil mill, it will be enough to purchase a screw oil press and a packing machine.

Personnel requirements

A major oil mill is often fully automated. Still workers are needed who will monitor the production technology and make timely adjustments... What kind of personnel is needed for the production of vegetable oils?

• workers with specialized technological and chemical education (foremen, technologists, engineers, chemists),
• freelance workers without bad habits (loaders, cleaners).

Large production in the workshop requires up to 50 people, it will be enough to hire 7 people for the oil mill.

In custody

The production of vegetable oil is a relatively inexpensive and profitable enterprise. But the instability of the final result and the lack of a quality certificate greatly narrow the markets for sale in large retail chains and stores. Still, a home creamery or mini-workshop will be a good start to start a business with further expansion to a factory.

Oil extraction is carried out in three main ways: pressing, centrifugation and extraction with organic solvents.

Oil production by pressing. Pressing is a mechanical squeezing of oil from pre-crushed oilseed raw materials (mint) on special screw presses.

When processing high-oil seeds, double pressing is used. This process includes pre-pickup

the main amount of oil on screw presses and the final oil recovery on high pressure presses. The preliminary extraction of oil is preceded by the stage of moisture-thermal processing of the mint.

Moisture heat treatment Peppermint helps to weaken the bonds of the oil with the particles of Peppermint, which makes it easier to separate the oil during pressing. The processed mint is called pulp and has a different structure. Moisture treatment consists in frying the mint and takes place in two stages. At the first stage, the moisture content of mint from sunflower seeds is brought to 8-9% and the temperature is up to 60 ° C. At the same time, water is absorbed by mint particles, which causes their swelling and an increase in plasticity. The connection between the oil and the swollen mint particles weakens, the oil is displaced onto the surface of the mint, and its viscosity decreases markedly. At the second stage, the mint is dried at a temperature of 105 ° C and the moisture content of the pulp from sunflower seeds is brought to 5-6%. At this stage, denaturation of protein substances occurs, the plastic properties of the pulp decrease, it acquires a more rigid structure, which ensures optimal oil extraction. The pulp supplied for pressing must have certain elastoplastic properties, temperature and humidity. Both the decrease and the excess of the pulp moisture content in comparison with the optimal one leads to a decrease in oil removal and increases the oil content in the pulp.

During the moisture-thermal treatment of cottonseed mint, conditions are created for the conversion of the poisonous pigment of gossypol into a physiologically inactive form. This is facilitated by the increased humidity and temperature of the mint, as well as the duration of the frying. The mode of frying the mint from cotton seeds is as follows: at the first stage, the humidity is brought to 11.5-13.5% at a temperature of 70-80 ° C, at the second stage, it is dried to a humidity of 4.5-5.5% at a temperature of 105-110 ° C.

Preliminary oil extraction. For pre-squeezing the oil, screw presses are used, called forpresses. The working bodies of the screw press are a split stepped cylinder and a screw shaft located inside it. The surface of the cylinder consists of steel plates and has longitudinal slots for oil drainage, into which particles of pulp do not pass.

The prepared pulp enters the stepped drum of the press, is captured by the turns of the screw shaft and moves to the outlet of the press. When moving along the drum of the press, the pulp is compressed, oil is separated from it, and the solid particles of the pulp are compressed and form cake. The pressure on the oilseed material increases as it moves along the axis of the shaft due to a decrease in the pitch of the turns of the screw shaft and the narrowing of the free space between the body of the screw shaft and the inner surface of the stepped drum. Forpresses can separate 60-85% of the oil. The oil content of the shmykh coming out of the forepress is up to 18%.

Preparation of oilseed material for final pressing. The final extraction of oil by pressing method is carried out from the pulp, which is obtained from the prepress cake. Forpress cake is crushed and subjected to moisture thermal processing.

Coarse grinding of the forpress cake is first carried out on disk or hammer crushers. After coarse grinding, the cake is subjected to fine homogeneous grinding on roller mills. The passage of cake particles through a sieve with a mesh size of 1 mm must be at least 80%.

The moisture-thermal treatment of the cake is carried out in a more severe mode in order to obtain a pulp with good plastic properties, ensuring effective oil separation during the final pressing. The crushed cake is moistened to 8-9%, then steamed to a temperature of 115-120 ° C and a humidity of 2.5-3.2%. Pulp from cotton seeds is dried to a moisture content of 3-4% and at a temperature of 1.10-115 С С.

The pulp from the prepress cake is fed to the screw presses for the final extraction of the oil. Deep oil take-off presses (expellers) are characterized by a lower productivity than pre-presses, but the compression ratio of the oil material in them is much higher. The resulting expeller cake should contain no more than 6% oil. The oil remaining in the cake is located in the undisturbed cells of the oilseed material, and is also retained on the surface of the cake particles.

Oil production by centrifugation method. The most common technology for producing olive oils is continuous centrifugation and separation. In the 1960s. firm Alfa-Laval(Sweden) has developed a method for producing olive oils - "centriolrve", which is taken as a basis for olive oil producers all over the world. According to this technology, the fruits are conveyed by a belt conveyor to the device for washing and removing leaves and trash. The washed olives go for grinding and then into the apparatus for making pasta from them, homogenizing and tempering it. When processing dry fruits, the paste is added warm water... The prepared paste enters a centrifugal extractor, where it is divided into three fractions: oil (with a low moisture content), water (with some oil content) and pomace. The oil and water phases are fed to the filtering vibrating screens, where they are freed from foreign suspensions. Then oil is separated on the separators, which has a moisture content of about 0.2%. Oil production is pumped into containers, where it is stored for 2-3 months. During this time, the remaining moisture under the influence gravitational forces sink to the bottom. The settled oil is passed through a filter paper of a filter press and packaged.

Obtaining oils by the extraction method. The extraction method for the extraction of oils is the most economical, provides maximum defatting of oilseeds, allows obtaining high quality oil and fat-free residue - meal.

When processing low-oil raw materials (soybean seeds and others), direct oil extraction is used, for defatting most high-oil seeds, oil is preliminarily isolated by pressing, and then sent for subsequent, final extraction by extraction. This is how the seeds of sunflower, cotton, flax, peanuts, etc. are processed.

The extraction process is based on the ability of vegetable oils to dissolve in organic solvents. In our country, “A” grade gasoline and nefrax are used as solvents for extracting oil from vegetable raw materials. Extraction gasolines belong to aliphatic hydrocarbons and are a mixture of saturated, unsaturated and small amounts of aromatic hydrocarbons. They have a boiling point of 63-95 ° C. Gasolines containing aromatic hydrocarbons dissolve well not only oil, but also fat-like substances (phospholipids, pigments, waxes), which degrade the quality of the oil. In addition, the use of gasoline with a boiling point range of 70-95 ° C makes it necessary to maintain high fever when distilling off the solvent from miscella and meal, which somewhat reduces the quality of the oil and meal obtained.

Usually, gasoline with a low boiling point (63-75 ° C) is used, containing a significantly lower amount of aromatic hydrocarbons, which improves the quality of the finished oil, reduces the content of associated impurities in it.

Olive oil from pomace and seeds is extracted with halogenated solvents (perchlorethylene, trichlorethylene and chloroform). In addition, the extraction olive oil can be carried out using supercritical carbon dioxide and enzyme complexes.

Extraction of oil from oilseed material by solvent occurs through molecular and convective diffusion, the driving force of diffusion is the difference in the concentration of oil inside the oilseed material and outside it. When the material to be extracted is mixed with the solvent, the surface of the material particles is wetted by the solvent, filling all the pores of the pulp structure. This dissolves the oil that is in a free state on the surface of the destroyed particles of the oil-bearing material. Further, the solvent penetrates the cell membranes and dissolves the oil in the undisturbed and deformed cells. The resulting solution of oil in a solvent, called miscella, under the action of the difference in copenstances, moves to the surface of the material to be extracted, comes out to its surface and passes into the solvent. The extraction rate depends on the condition of the oilseed material, its temperature and humidity. The extraction of free oil proceeds most rapidly, while oil is extracted slowly from intact cells. Therefore, when preparing the oilseed material, it is necessary to destroy its cellular structure as much as possible and release the oil. To ensure good advancement of the solvent through the oily material, it is necessary that the particle size of the destroyed cells is 0.5-1 mm and that there is a certain particle shape - petal, grains, granules.

Raising the process temperature significantly speeds up the extraction. An increase in the moisture content of the extracted material slows down the extraction process. Optimum moisture content during processing of sunflower seeds is no more than 8-10%, cotton - no more than 8%.

The prepress cake for the final extraction of the oil by the extraction method undergoes a special treatment. Initially, the cake is crushed in hammer or disk crushers, destroying the whole cells of the oilseed material and the structures formed during the pressing process.

Then they carry out the moisture-thermal processing of the meal crumbs in vat braziers to increase the plasticity of the oilseed raw materials. The moisture content of the oil-bearing material from sunflower seeds is adjusted to 8-9%, the temperature - to 50 ° C. The semolina, conditioned by humidity and temperature, is fed to two-pair flattening roller machines, where it takes the shape of a petal with a thickness of 0.25-0.5 mm. Obtaining oil cake is used in preparation for the extraction of forepress cake from sunflower seeds, flax, peanuts, etc. Cotton cake comes for extraction in the form of crumbs, so the stage of its petalization is excluded.

Soybean seeds are low-oil crops, so it is more efficient to extract oil from them by direct extraction. Soybean seeds are cleaned of impurities, they are subjected to moisture-thermal processing and crushed on single-pair corrugated roller mills. The resulting crushed material is separated, and the cleaned kernels are fed to the inactivator screw, where the moisture content of the kernels is brought to 15%, and the temperature is brought to 80-90 ° C. Then, in a vat brazier, the crushed kernel is treated with moisture and heat, its moisture content drops to 8-9.5%, and the temperature drops to 60-70 ° C. The prepared core is fed to two-pair flattening roller machines, where a lobe 0.3 mm thick is formed.

The processing of soybean seeds to obtain food meal requires thorough cleaning from weeds and metal impurities, as well as the removal of the shell and embryo, which reduce nutritional value meal.

Extraction of oil from oilseeds is carried out in two ways: immersion and stepwise irrigation.

Immersion extraction occurs in extractors in the process of continuous passage of raw materials through a continuous flow of solvent in countercurrent conditions, when the solvent and raw materials move in the opposite direction relative to each other. Such an extractor consists of a loading column, a horizontal cylinder and an extraction column, inside which screws are installed. Raw material in the form of a petal or grains enters the loading column, is picked up by the screw turns, moves to the bottom of the loading column, passes the horizontal cylinder and enters the extraction column, where it rises to its upper part with the help of the screw. Simultaneously with the raw material, gasoline with a temperature of 55-60 ° C is fed into the extractor. Gasoline moves towards the feedstock and passes through the extractor, horizontal cylinder and loading column. The concentration of miscella at the outlet of the extractor is 15-17%.

Low-fat residue of raw materials - meal comes out of the extractor with a high content of solvent and moisture (25-40%), so it is sent to auger or vat (toasters) evaporators, where gasoline is removed from it.

The advantages of immersion extraction include: high extraction rate, simplicity of the design solution of the extraction apparatus, and the safety of their operation. The disadvantages of this method are: low concentrations of final miscella, high content of impurities in miscella, which complicates their further processing.

Extraction by means of staged irrigation. In this method, only the solvent moves continuously, and the raw material remains at rest in the same moving container or moving belt. This method provides for obtaining miscella of increased concentration (25-30%), with a smaller amount of impurities. The disadvantages of this method are the long duration of the extraction, the increased explosiveness of the production.

The miscella coming out of the extractor may contain from 15 to 35% oil dissolved in the extractant, as well as some impurities. Miscella processing is carried out in two stages: miscella cleaning; distillation of the solvent - distillation of the miscella.

Cleansing the miscella. Extraction miscella contains solid meal particles in the amount of 0.4-0.1%. The presence of solid impurities significantly complicates the process of stripping the solvent from the miscella and reduces the quality of the finished oil. To purify the miscella, sedimentation and filtration are used. The settling of the miscella is carried out in decanters of some vertical screw extractors.

Purification of miscella from solid impurities by filtration is widely used. A layer of sediment is formed on a filtering baffle made of belting, nylon, nylon. During the initial filtration period, solid particles accumulate on the surface of the filter baffle. Further filtration of the miscella passes through a layer of sediment, which retains solid impurities. These filters require periodic cleaning of the filtering surface from the sediment layer. The cleaned miscella should contain no more than 0.02% sludge.

Separation of miscella into oil and solvent carried out by distilling the volatile solvent from the non-volatile oil. During distillation, it is necessary to achieve rapid and complete removal of the solvent from the oil with as much low temperatures.

However, when the solvent is distilled off, the boiling point of the miscella rises simultaneously with an increase in its concentration. Therefore, first, the solvent is distilled off by evaporation at atmospheric pressure, then the solvent is distilled off under vacuum to lower the distillation temperature. But even under deep vacuum conditions, it is not possible to completely remove the solvent from the oil, as this requires maintaining a high temperature, which can lead to decomposition of the oil. A significant acceleration of the distillation process and a decrease in temperature occurs when the solvent is distilled off with live steam at atmospheric pressure or under vacuum.

Miscella distillation is the stripping of the solvent from the miscella. The most common three-stage distillation schemes.

In the first two stages, the miscella is processed in tubular film stills. At the first stage, the miscella is evaporated. On the second stage, the miscella is treated with live steam at a temperature of 180-220 ° C and a pressure of 0.3 MPa, which causes the miscella to boil and the formation of solvent vapors. The solvent vapors are directed to the condenser. At the third stage, highly concentrated miscella enters a spray vacuum distiller, where, as a result of bubbling with live steam at a pressure of 0.3 MPa, the final removal of solvent traces occurs. After distillation, the oil is sent for refining.

Meal processing. The oil-free meal during the extraction process can contain from 25 to 40% solvent and water. The solvent is in the meal in a bound state, in the form of miscella. It is removed by distillation. Distillation of the solvent from the meal in a stirred layer is carried out in vat evaporators (toasters), in which the meal is treated with live steam with stirring. If necessary, the meal is moistened before stripping off the solvent. In the process of steaming the meal, it is possible to create conditions for moisture thermal treatment, in which toxic substances contained in cotton, soybean and peanut meal are neutralized. As a result of such processing, the nutritional and feed value of the meal increases. The duration of distillation of the solvent from the meal is 55-60 minutes. The meal temperature at the exit from the evaporator is 100-105 ° C, the humidity is 8-10%. The residual solvent content in the meal is not higher than 0.05%.

After removing the solvent in a vat evaporator, the meal is cooled to a temperature not exceeding 40 ° C. For storage, sunflower meal should have a moisture content of no more than 7-9%, a temperature of no more than 40 ° C, and a solvent content of no more than 0.1%.

In the oil-extracting industry, the meal is enriched with lipids and its subsequent granulation. During enrichment, oil refining waste is added to the meal - soap stock or hydration fus, which significantly increases the feed value of the meal. Then the fortified meal is granulated. Granulated meal has a number of advantages: it does not generate dust during transportation, takes up less volume, has a high content of nutrients and digestibility, and is convenient when composing feed for animals.

The enrichment of the meal with lipids and granulation consists in the preparation of an emulsion of lipids with water, mixing the meal with the emulsion, heating, pressing and cooling the granules. The meal enters the brazier, where it is mixed with an emulsion containing 35-40% lipids and 60-65% water; the temperature of the lipid emulsion is 50-60 ° C. In a roasting pan, the mixture is heated to 80 ° C and enters the pellet press. Granulated meal passes through the cooler and is sent to storage. After processing, granulated sunflower meal should contain 3-3.5% lipids and 9-11% moisture.

The production of some food products looks like a sabotage of the country's food security. Now, with the abolition of compulsory certification, the manufacturer does not have rigid boundaries in food production. And there is no longer the task of preserving the beneficial properties of natural raw materials. There is only one goal - profit. The buyer needs to keep this in mind and be more critical in his food choices. In this post, let's talk about vegetable oil, and specifically about its production. So what's wrong with butter?

Currently, more than 50 oil crops are used for the production of vegetable oil. Still, the most common is sunflower seed oil. There are three ways to make oil: cold pressed, hot pressed and extracted.

Cold pressing involves cleaning seeds, grinding and extracting oil from the seed. The oil is perishable, but retains all the beneficial properties of the plant product: tocopherols are vitamins A, E, D, vitamin F, polyunsaturated and monounsaturated fatty acids, phytosterols - substances with atherosclerotic and anti-cancer effects and other useful substances.

The hot pressing method differs in that the prepared seed is heated and fried before the oil is extracted. From this, the finished oil becomes more aromatic and also retains all the beneficial substances.

These two methods allow you to get the so-called. crude, unrefined oil, with a short shelf life, with high taste and nutritional properties. Such oil is only defended and filtered. Little obtained by the method of cold pressing and hot pressing is mainly not used in heat treatment, since it has a low smoke threshold of +107 degrees C.

The most barbaric and profitable way to obtain oil is extraction. In this way, refined and unrefined oils are obtained. After grinding and cleaning, the seeds are immersed in a solvent. To do this, use grade A gasoline or hexane.

As a result, miscella is obtained - this is oil dissolved in gasoline, and meal - a dry fat-free residue. Further, the solvent is "expelled" from the miscella and meal in special devices. This oil is subject to further processing. First, it is cleaned of impurities, defended, filtered, centrifuged. The finished oil goes to store shelves in the form of commercial unrefined oil, which is positioned as more useful than refined oil.

To obtain refined oil, additional purification methods are used. Hydration - treatment with hot water and steam, during this treatment, the particles remaining in the oil swell and precipitate. In order to prevent such oil from oxidizing and not going rancid, it is treated with alkali - alkaline refining. In this way, fatty acids, which are very necessary for our body, are removed. Fatty acids react with alkali and precipitate.

The process of producing refined vegetable oil does not always end there. If there are also other cleaning methods: bleaching - removal of dyes, deodorization - extraction of aromatic substances and freezing - removal of waxy substances.

This oil turns out to be almost colorless, tasteless and odorless, it is well stored, the smoke point is more than +230 degrees C.

You do not need the education of a chemist to understand that after such executions the natural molecules of fatty acids no longer remain the same. The extraction process disfigures these molecules, converting them into trans isomers, i.e. trans fats, of which there are more than 20% in oil, both refined and not refined by the extraction method. Trans fats accumulate in the body and cause various disorders in cardiovascular system... Trans isomers are excreted from the body within 2 years if a person completely stops using them. In addition, particles of solvent and other chemicals used in the extraction process remain in the oil.

The technology of oil production using extraction is the most cost-effective, as it allows to produce up to 99% of oil from raw materials. When buying oil, the buyer needs to read the label carefully. If the label does not indicate how the oil was obtained, then most likely it was the extraction method.