JPH06299189A - Method for continuously purifying lecithin - Google Patents

Abstract

PURPOSE:To effectively remove oils from lecithin with acetone as an extracting solvent according to a countercurrent method and continuously obtain the purified lecithin. CONSTITUTION:Lecithin is continuously purified. In the process, a dispersion is prepared by finely dispersing pasty oil-containing lecithin as fine particles with <=16% oil content in acetone and then fed to the upper part of an extraction column 10. On the other hand, acetone as an extracting solvent is fed from the lower part of the extraction column 10 according to a countercurrent method to extract the oils from the fine particulate lecithin descending in the interior of the extraction column 10. Thereby, the lecithin is taken as the acetone dispersion of the purified lecithin particles from an outlet 24 in the lower part of the extraction column 10.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a continuous purification method of lecithin, and in particular, paste-like oil-containing lecithin, in other words, paste-like lecithin containing phospholipid as a main component and containing fats and oils derived from raw materials, and acetone as an extraction solvent. The present invention relates to a method for producing high-purity lecithin by extracting and removing the oil component using.

[0002]

BACKGROUND ART Lecithin, which is widely used as an emulsifier, a dispersant, etc. in various fields of food, cosmetics, pharmaceuticals, and general industry, is obtained from oil seeds such as soybeans and animal raw materials such as egg yolks. Although its main component is phospholipid, it also contains oil components such as fats and oils derived from raw materials. For example, pasty soybean lecithin contains 40% or less, usually about 35 to 40% oil as an acetone-soluble component. However, such an oil component is an impurity, and its presence causes various problems in each application, and it is desired to provide lecithin of high purity and high quality.

For this reason, various studies have been made so far regarding the production of high-purity lecithin. In any case, basically oils and fats are dissolved but phospholipids are not. A method of extracting paste lecithin with a solvent is adopted, and acetone is generally used as the extraction solvent. For example, in Japanese Unexamined Patent Publication (Kokai) No. 50-140500, lecithin in paste form is added to cold acetone and stirred at high speed to elute the oil in lecithin into acetone, and then decantation of the precipitated granular lecithin and the supernatant is carried out. A method has been proposed in which high purity lecithin is obtained by repeating the procedure of separating by precipitation, adding cold acetone to the precipitate again, stirring and extracting.

However, in the conventional method using acetone, in order to purify the lecithin in the form of particles, the extraction operation of adding acetone, stirring and separating by sedimentation is repeated by a batch method. There was a problem that high-purity lecithin could not be obtained unless it was repeated. Also, it is possible to collect the particulate lecithin on, for example, a wire mesh of an appropriate mesh, and to filter and wash with acetone. However, since the filtration resistance of lecithin particles is large, the amount of lecithin that can be deposited on the wire mesh is large. Has a limit, and therefore, the lecithin particles that have been treated must be frequently wiped from the wire net, and the operation thereof is complicated. Moreover, in filtration and washing operations of lecithin particles, since the lecithin particles containing oil are sticky, there is an inherent problem that cleaning efficiency and work efficiency are poor. For these reasons, conventionally, as previously pointed out, the batch method was mainly used to extract the oil content of lecithin, and solid-liquid separation relied on decantation, so cleaning efficiency and processing speed were increased. It had a problem with.

[0005]

The present invention has been made in view of such circumstances, and the object thereof is to effectively remove oil from lecithin by a countercurrent method using acetone as an extraction solvent. The purpose is to provide a method by which purified lecithin can be continuously obtained.

[0006]

In order to solve such a problem, the present invention comprises a method for continuously purifying lecithin, in which pasty oil-containing lecithin is finely dispersed in acetone as fine particles having an oil content of 16% or less. After preparing the dispersion,
The dispersion is supplied to the upper part of the extraction column, while acetone as an extraction solvent is supplied from the lower part of the extraction column in a countercurrent method to extract oil from the fine particle lecithin descending in the extraction column. The method employs a method characterized in that the purified lecithin particles are taken out as an acetone dispersion from the lower outlet of the extraction column.

[0007]

[Concrete Construction / Operation] In summary, the present invention as described above is
When the oil content in the lecithin particles packed in the same manner as in the column in the column chromatograph is eluted with acetone, the oil content in the eluate sharply decreases at the point where the void volume is exceeded, that is, the extraction rate of the oil content with acetone. It was completed based on the fact that it was found to be fast, and the particulate lecithin was selected for extraction. This particulate lecithin will be prepared as a dispersion (dispersion) having a particle size as uniform as possible by stirring a mixture of oily lecithin in paste and acetone at high speed. Fine particles (oil-containing lecithin) are also used to prevent reaggregation or adhesion of the oil-containing lecithin particles.
Oil content of 16% (by weight) or less, preferably 1
It is necessary to set 0 to 14%, and with this,
The oil concentration in the dispersion becomes 8% or less, preferably about 3 to 6%.

By the way, such a fine particle dispersion of oil-containing lecithin can be prepared by various known methods, but in general, the acetone-soluble content (oil content) is 35.
It can be obtained by using a normal oily lecithin in the form of -40% and stirring it at high speed while injecting it into acetone. At that time, with respect to the paste-like oil-containing lecithin, acetone was 4 times by weight (5 times by volume) or more,
It is preferably used in a proportion of about 6 to 8 times by weight (7.5 to 10 times by volume), whereby oil content is extracted from the pasty lecithin into the dispersion medium (acetone), and reaggregation of the particulate lecithin is performed. A dispersion of lecithin fine particles having an oil content of 16% or less, which does not occur, can be advantageously prepared. In addition to pure acetone, it is also possible to use dilute oil-impregnated acetone separated in the process of the present invention as acetone as a dispersion medium for dispersing the pasty lecithin.

The particle size of the lecithin particles in the dispersion is preferably 75% or more of particles having a particle size of 0.3 mm or less, and does not include particles having a particle size of 2 mm or more.
When the particle size of the lecithin fine particles in such a dispersion becomes large, the apparent density of the obtained product becomes high, it is difficult to dry, the extraction takes time, and the content of acetone-soluble components in the product becomes high. Etc. causes problems.

The equipment used for producing the above-mentioned dispersion liquid of lecithin fine particles is as follows:
First, it is desirable to make fine pasty lecithin droplets and disperse them in acetone to facilitate the extraction of the oil component. Not only is it difficult to granulate, it takes a long time to extract,
It is difficult to achieve the target oil content of 16% or less, which wastes energy and time, so it is desirable to avoid it. In this respect, it is preferable that the stirrer has a stirring action that spreads over the entire container, and that the paste-like lecithin is extruded into the acetone from the porous nozzle to stir, or a high-speed homomixer as a high-speed stirrer. In addition, it is recommended to use a continuous wet pulverizer or a disperser as a continuous device, for example, a homomic line flow (made by Tokushu Kika Kogyo), an attritor (made by Mitsui Miike Kogyo) or the like.

Further, in the present invention, as described above, prior to directly atomizing paste-like oil-containing lecithin into acetone, such oil-containing lecithin is subjected to a liquid-liquid extraction operation in advance. Are also appropriately adopted. Under the dispersing conditions such that the oil content in lecithin exceeds 16%, lecithin does not become particles and becomes a liquid homogeneous phase, and most of the oil content is transferred to the acetone layer, which can be removed. For example, for paste lecithin at room temperature,
The target dispersion can be obtained by adding 2 parts by weight of acetone to the liquid lecithin obtained by liquid-liquid extraction by adding an equal weight of acetone and atomizing it by the above-mentioned method. Therefore, the amount of acetone can be saved as a whole.

The lecithin fine particle dispersion thus obtained has a solid content (particles) concentration appropriately adjusted for the subsequent continuous extraction operation with acetone, and an excess dispersion medium is added if necessary. (Extract) is removed in advance.
The separated and removed dispersion medium will be recovered and reused by distillation. In addition, the solid content concentration in the lecithin fine particle dispersion is generally 40% or less, preferably about 20 to 30%. If this solid content concentration is too high, problems will occur in the transport capacity of the pump and the particle dispersion capacity in the extraction device, and if the concentration is too low, excess oil-containing dispersion medium will be used. This causes problems such as a decrease in extraction efficiency due to the supply.

In the present invention, the thus obtained dispersion of lecithin fine particles is used and supplied to the upper part of the extraction column, while acetone as an extraction solvent is supplied from the lower part of the extraction column in a countercurrent system. The oil is extracted from the finely divided lecithin flowing down in the extraction column, and thus the acetone dispersion of the purified lecithin particles is taken out from the lower outlet of the extraction column. The basic concept of a device capable of performing different extraction operations is shown in FIG.

That is, in the continuous extraction apparatus shown in FIG. 1, 10 is an extraction column, the inside of which is partitioned by a porous plate 12 into a plurality of stages. Then, stirring blades 16 rotated by the driving device 14 are arranged so as to be located in the respective spaces between the perforated plates 12. In addition, at the upper portion of the extraction column 10, a lecithin dispersion liquid supply port 18 and an extraction liquid outlet 20 are provided.
On the other hand, a supply port 22 for acetone as an extraction solvent and a purified lecithin fine particle dispersion liquid outlet 24 are provided at the lower part thereof, respectively. The length of the extraction column 10 is determined by the retention (fall) of the lecithin fine particles subjected to the acetone extraction operation inside the extraction column 10.
It will be determined in consideration of time, the presence of a partition plate such as the perforated plate 12 and the stirring action of the stirring blades 16, but generally, the oil content in the purified lecithin is a target value. Will be determined to be 100 seconds or more.

Therefore, in the continuous extractor having such a structure, the fine particle dispersion of oil-containing lecithin prepared as described above is supplied from the dispersion supply port 18 of the extraction column 10 while extraction is performed. Acetone as an extraction solvent is supplied from an acetone supply port 22 provided in the lower part of the column 10, and under stirring by the stirring blade 16, both of them, particularly acetone as an extraction solvent, are directed toward the lecithin particles that settle. It is made to contact in a flow form. That is, the lecithin particles introduced into the upper part of the extraction column 10 are settled due to the difference in specific gravity with acetone to desorb fats (oils), and the lecithin particles which have been extracted by such desorption are discharged at the lower outlet. It is taken out as an acetone dispersion of purified lecithin particles from (24).

Further, the specific gravity of the extract produced by such an extraction operation is higher than that of pure acetone, but the supply rate of acetone from the acetone supply port 22 is set to the outflow rate of the acetone dispersion of precipitated lecithin (particles). By setting the flow path adjusting plate (12) larger than the above and installing an appropriate flow path adjusting plate (12) in the extraction column 10, acetone rises while eluting the oil component in lecithin, and as an extract from the upper outlet (20). It will be leaked. Incidentally, the relative sedimentation rate of the lecithin particles, and the relationship between the upward flow of acetone, can be appropriately determined within the range in which the specific gravity difference between acetone or acetone extract and lecithin particles can be used, Generally, in the flow rate relationship between the lecithin dispersion and acetone as the extraction solvent, one of such lecithin dispersions is used.
Acetone as an extraction solvent is 1.5 parts by weight based on 1.5 parts by weight.
-3 parts by weight will be used.

The oil content in the refined lecithin (particles) taken out from the dispersion liquid outlet 24 at the lower part of the extraction column 10 through such extraction operation is reduced to 3% or less as an acetone-soluble content. Therefore, lecithin with good purification can be continuously obtained.

A known separation method is applied to the acetone dispersion liquid of purified lecithin extracted from the extraction column 10 in this manner, for example, acetone removal by a physical method such as filtration or centrifugation, or vacuum removal. An operation such as complete removal of acetone by heating and drying is carried out, and the purified lecithin powder is provided for various uses. Further, even if the extraction liquid (acetone) taken out from the extraction liquid outlet 20 at the upper part of the extraction column 10 is properly recovered and reused, for example, such an extraction liquid is prepared in the paste form described above. It can also be used as a dispersion medium for producing a dispersion of particulate oil-containing lecithin from lecithin, and does not necessarily need to be recovered by distillation.

[0019]

EXAMPLES Some examples of the present invention will be shown below to clarify the present invention in more detail. However, the present invention is not limited by the description of such examples. Needless to say, it is not something to receive. In addition to the following embodiments, the present invention further includes various changes and modifications based on the knowledge of those skilled in the art, in addition to the above specific description, without departing from the spirit of the present invention. It is to be understood that improvements, etc. can be added.

Example 1 First, 3 liters of acetone was placed in a beaker of 5 liters, and a tabletop homomixer (made by Tokushu Kika Kogyo Co., Ltd.) was used.
While stirring at 0 rpm, 320 g of paste oil-containing lecithin (acetone-soluble content = 37%) was continuously and gradually flowed down, and finely pulverized in acetone to obtain fine oil-containing lecithin particles. A dispersed dispersion was prepared. Next, the obtained dispersion liquid was allowed to stand still, and then the supernatant liquid was removed to obtain a 1-liter dispersion liquid.
Then, by repeating this operation, a dispersion liquid of lecithin fine particles of 10 liters in total was prepared. The dispersion contained lecithin corresponding to about 2 kg (solid content: about 25%), the average particle size of the lecithin particles was about 100 μm, and the oil content in the lecithin particles was 10.5.
%, And the oil concentration in the dispersion liquid (acetone) was 4.26%.

On the other hand, as the extraction device, a structure similar to that shown in FIG. 1 is adopted, and the glass tube providing the extraction column has a straight body length of 677 mm and an inner diameter of 74.7 mm.
The size was used. Then, in this glass tube, perforated plates were provided in 9 stages with a plate spacing of 50 mm, and stirring blades were arranged in the space partitioned by the perforated plates in the same manner as in FIG. As the perforated plate, a plastic plate (aperture ratio of 46%) having a large number of holes of 5 mmφ was used.

With respect to such an extractor, the introduction position of the dispersion liquid is adjusted through a glass tube having an inner diameter of 8 mm provided as a dispersion liquid supply port, and the lecithin dispersion liquid is stirred through the glass tube. While maintaining its dispersed state, it was introduced into a glass tube as an extraction column by supplying with a metering pump. Further, the insertion position of a glass tube having an inner diameter of 8 mm as an acetone supply port provided in the lower part of the glass tube as the extraction column was adjusted to adjust the introduction position of acetone through the glass tube. Then, acetone was supplied through the glass tube by a metering pump and introduced into the glass tube as an extraction column. The extract was taken out as an overflow liquid (overflow) of a glass tube as an extraction column, and the purified lecithin was taken out as a bottom flow liquid (underflow) with a metering pump in an acetone dispersion state. Then, such an underflow was filtered, further dried under vacuum at a temperature of 60 ° C., and collected as a purified lecithin powder.

Then, according to such an extraction operation, the above lecithin dispersion is continuously extracted under various extraction conditions (dispersion liquid flow rate, acetone flow rate, overflow liquid flow rate, bottom flow liquid flow rate). The results are shown in Table 1 below. As is clear from the results of Table 1, it can be well recognized that according to the method of the present invention, purified lecithin powder having a low concentration of acetone-soluble components can be easily obtained in a large amount. is there.

[0024]

[Table 1]

Example 2 A continuous disperser (manufactured by Tokushu Kika Kogyo Co., Ltd., a homomic line flow for testing) was used, and acetone was continuously supplied thereto at a rate of 9.0 kg / min, and at the same time, a paste was formed. Oil-containing lecithin (oil content 38%) was extruded from a nozzle at a speed of 1.5 kg / min and supplied, and the rotation speed was 5000 rpm.
By stirring at the rotation speed of, a dispersion liquid in which fine particles of oil-containing lecithin were dispersed was obtained. Then, 27 liters of the obtained dispersion liquid was allowed to stand, 17 liters of the supernatant liquid was removed, and the remaining 10 liters were used as a lecithin dispersion liquid for continuous extraction. The solid content concentration of this dispersion was 22%, the average particle size of the dispersed particles was 170 μm, the oil content of the dispersed particles was 11.9%, and the oil content of the acetone dispersion medium was 5.03%.

On the other hand, as the extraction device, the device having the same structure as that of the first embodiment was adopted except for the specifications of the perforated plate, the number of stages, and the plate interval. As the perforated plate, a plastic plate (aperture ratio 23%) provided with a large number of holes of 8 mmφ was used, and the number of steps was 12 steps. Furthermore, the plate spacing of this perforated plate is 36 mm.
And

A continuous extraction operation of the lecithin dispersion liquid with acetone using such an extraction device was performed under various extraction conditions (dispersion liquid flow rate, acetone flow rate, overflow liquid flow rate, bottom flow liquid flow rate), and the results were obtained. The results are shown in Table 2 below. As is clear from the results, purified lecithin with an acetone-soluble content of 3% or less was used.
I was able to get it easily in a short time.

[0028]

[Table 2]

[0029]

As is clear from the above description, according to the method for continuously purifying lecithin according to the present invention, since the purification (extraction) operation is carried out in the continuous countercurrent system, its efficiency is high. It is significantly superior to the conventional batch system and saves extraction solvent. Further, it is possible to continuously obtain lecithin having a high degree of purification, and there is a great advantage in that the process is rationalized in terms of time, labor and cost. In addition, the method of the present invention can be applied to the purification of fractionated lecithin having a high oil content and the purification of enzyme-treated / degraded lecithin.
It has the advantage that it can be applied.

As described above, the method of the present invention is extremely useful as a method for producing a purified lecithin powder suitable for industrial production, which can achieve good productivity and can effectively achieve simplification of the process. It is expensive.

[Brief description of drawings]

FIG. 1 is a basic conceptual diagram showing an example of an extraction device to which the method of the present invention is applied.

[Explanation of symbols]

10 Extraction Column 12 Perforated Plate 14 Drive Device 16 Stirring Blade 18 Dispersion Liquid Supply Port 20 Extraction Liquid Outlet 22 Acetone Supply Port 24 Purified Lecithin Dispersion Liquid Outlet

Claims (1)

[Claims] 1. A paste is prepared by finely dispersing oil-containing lecithin in the form of fine particles having an oil content of 16% or less in acetone, and then supplying the dispersion to the upper part of the extraction column. Acetone as an extraction solvent was supplied from the lower part of the extraction column in a countercurrent method to extract oil from fine particle lecithin descending in the extraction column, and lecithin particles purified from the lower outlet of the extraction column. The method for continuous purification of lecithin is characterized in that it is taken out as an acetone dispersion liquid of.