JP2758343B2 - Method for continuous purification of lecithin - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for continuously purifying lecithin, and more particularly to a paste-like oil-containing lecithin, in other words, a 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 the method.

[0002]

BACKGROUND ART Lecithin, which is widely used as an emulsifier and dispersant in the fields of food, cosmetics, pharmaceuticals, and general industry, is obtained from oil seeds such as soybeans and animal raw materials such as egg yolk. The main component is a phospholipid, but also contains an oil component such as a fat or oil derived from a raw material. For example, pasty soy lecithin contains an oil soluble in acetone of 40% or less, usually about 35 to 40%. However, such oils are impurities, and their existence causes various problems in various applications, and it is desired to provide high-purity, high-grade lecithin.

For this reason, various studies have hitherto been made on the production of high-purity lecithin. In any case, basically, fats and oils are dissolved, but phospholipids are not. A method of extracting paste lecithin with a solvent is employed, and acetone is generally used as the extraction solvent. For example, in Japanese Patent Application Laid-Open No. 50-140500, paste lecithin is added to cold acetone, and the mixture is stirred at high speed to elute the oil in lecithin into acetone. A method has been proposed in which cold acetone is added to the precipitate again, and stirring and extraction are repeated to obtain high-purity lecithin.

However, in the conventional method using acetone, in order to purify the lecithin that has been made into particles, acetone is added, and an extraction operation of stirring and sedimentation is repeated in a batchwise manner. Otherwise, high purity lecithin cannot be obtained. In addition, a method of collecting the lecithin that has been made into particles, for example, on a wire mesh having an appropriate mesh, and filtering and washing with acetone can be considered. Has a limitation, and therefore, the processed lecithin particles must be frequently removed from a wire mesh, and the operation is complicated. In addition, in the operation of filtering and washing lecithin particles, since the lecithin particles containing oil are sticky, there is also a problem that washing efficiency and work efficiency are poor. For these reasons, as previously pointed out, the batch method has been used exclusively for the extraction of lecithin oil, and solid-liquid separation relied on decantation. Had a problem.

[0005]

The present invention has been made in view of the above circumstances, and it is an object of the present invention to effectively remove oil from lecithin in a countercurrent method using acetone as an extraction solvent. Accordingly, it is an object of the present invention to provide a method capable of continuously obtaining purified lecithin.

[0006]

According to the present invention, as a method for continuously purifying lecithin, a paste-like 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, and acetone as an extraction solvent is supplied in a countercurrent manner from the lower part of the extraction column to extract an oil component from fine lecithin descending in the extraction column. And extracting the purified lecithin particles as an acetone dispersion from the lower outlet of the extraction column.

[0007]

[Specific structure and operation] In short, the present invention as described above
When eluting the oil component in the lecithin particles packed with acetone in the same manner as in the column in column chromatography with acetone, the oil component in the eluate drops sharply at a point almost past the void volume, that is, the extraction rate of the oil component by acetone. Based on the fact that it was found to be fast, it was completed and the particulate lecithin was targeted for extraction. This particulate lecithin is prepared as a dispersion (dispersion) having as uniform a particle diameter as possible by rapidly stirring a mixture of paste-like oil-containing lecithin and acetone. In order to prevent the re-aggregation or adhesion of the oil-containing lecithin fine particles therein, the fine particles (oil-containing lecithin)
Has an oil content of 16% (by weight) or less, preferably 1%.
It is necessary to be about 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 an oil-containing lecithin fine particle dispersion can be prepared by various known methods, and generally, the acetone-soluble component (oil component) is 35%.
It can be obtained by using ペ ー ス ト 40% of ordinary paste-like oil-containing lecithin, and pouring it into acetone and stirring it at high speed. At that time, acetone was 4 weight times (5 times volume) or more with respect to the paste-like oil-containing lecithin,
Preferably, it is used at a ratio of about 6 to 8 times by weight (7.5 to 10 times by volume), whereby oil is extracted from the paste lecithin into a dispersion medium (acetone), and reagglomeration of the particulate lecithin is performed. A dispersion of lecithin microparticles having an oil content of 16% or less, at which no occurrence of the above-mentioned problem, can be advantageously prepared. As acetone as a dispersion medium for dispersing the pasty lecithin, dilute oil-containing acetone separated in the process of the present invention can be used in addition to pure acetone.

The particle size of the lecithin microparticles in the dispersion is desirably 75% or more of particles having a particle size of 0.3 mm or less and not including particles having a particle size of 2 mm or more.
When the particle size of the lecithin microparticles in such a dispersion is large, the apparent density of the obtained product is high, and it is difficult to dry, it takes time for extraction, and the content of acetone-soluble matter in the product is high. And so on.

[0010] The equipment used for the production of the above-mentioned dispersion of lecithin fine particles is as follows.
First, it is desirable to make fine droplets of paste-like lecithin and disperse it in acetone to facilitate the extraction of oil.In the case of simply mixing and stirring lecithin and acetone, a mass Not only is difficult to granulate, but also takes time to extract,
It is difficult to achieve the target oil content of 16% or less, which wastes energy and time. In this regard, the stirrer preferably has a stirring action that extends over the entire vessel. The stirrer extrudes the lecithin paste into the acetone from a perforated nozzle and stirs the mixture. It is recommended to use a continuous wet pulverizer or a disperser as a continuous device, for example, a device such as a homomic line flow (manufactured by Tokushu Kika Kogyo) or an attritor (manufactured by Mitsui Miike Kogyo).

Further, in the present invention, as described above, prior to directly pulverizing the oil-containing lecithin in a paste form in acetone, a liquid-liquid extraction operation is performed on such oil-containing lecithin in advance. Is also adopted as appropriate. Under a dispersion condition in which the oil content in lecithin exceeds 16%, lecithin does not form particles, but becomes a liquid homogeneous phase, and most of the oil is transferred to the acetone layer, which can be removed. For example, for lecithin in paste at room temperature,
A target dispersion can be obtained by adding an equal weight of acetone, adding a liquid lecithin obtained by liquid-liquid extraction, and further adding acetone twice as much as the weight of the liquid lecithin, and pulverizing the mixture by the above-described method. Therefore, the amount of acetone can be saved as a whole.

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

In the present invention, a dispersion of lecithin fine particles thus obtained is used and supplied to the upper part of an extraction column, while acetone as an extraction solvent is supplied in a countercurrent manner from the lower part of the extraction column. The oil is extracted from the particulate lecithin that is supplied and descends in the extraction column, whereby an acetone dispersion of the purified lecithin particles is taken out from the lower outlet of the extraction column. FIG. 1 shows the basic concept of an apparatus capable of performing various extraction operations.

That is, in the continuous extraction apparatus shown in FIG. 1, reference numeral 10 denotes an extraction column, the inside of which is partitioned by a perforated plate 12 into a plurality of stages. And the stirring blade 16 rotated by the drive device 14 is arranged so as to be located in each space between the perforated plates 12. Further, a supply port 18 for the lecithin dispersion and an extract outlet 20 are provided at the upper part of the extraction column 10.
On the other hand, a supply port 22 for acetone as an extraction solvent and an outlet for purified lecithin fine particle dispersion liquid 24 are provided at the lower portion thereof. 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.
This is determined in consideration of the time, the presence of the partition plate such as the perforated plate 12 and the stirring action of the stirring blade 16, but generally, the oil content in the purified lecithin is a target value. Is determined so that the time to reach is not less than 100 seconds.

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

Although the specific gravity of the extract produced by such an extraction operation is higher than that of pure acetone, the rate of supply of acetone from the acetone supply port 22 is reduced by the flow rate of the acetone dispersion of precipitated lecithin (particles). Acetone rises while eluting the oil content in lecithin by installing a suitable flow path adjusting plate (12) in the extraction column 10, and as an extract from the upper outlet (20). It is leaked. Incidentally, the relative sedimentation velocity of the lecithin particles, the relationship between the rising flow of acetone can be appropriately determined within a range where the specific gravity difference between the acetone or the acetone extract and the lecithin particles can be used, In general, regarding the flow rate relationship between the lecithin dispersion and acetone as an extraction solvent, the ratio of the lecithin dispersion is 1%.
Acetone as an extraction solvent is 1.5 to parts by weight.
It will be used in a proportion of up to 3 parts by weight.

After the extraction operation as described above, the oil content in the purified lecithin (particles) taken out from the dispersion outlet 24 at the lower part of the extraction column 10 is reduced to 3% or less as an acetone-soluble matter. As a result, lecithin with a high degree of purification can be continuously obtained.

A known separation method is applied to the acetone dispersion of purified lecithin thus taken out from the extraction column 10, for example, acetone removal by a physical method such as filtration or centrifugation, and vacuum removal. An operation such as complete removal of acetone by heating and drying is performed, and the purified lecithin powder is provided for various uses. Also, the extract (acetone) taken out from the extract outlet 20 at the upper part of the extraction column 10 is appropriately collected and reused. 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 Hereinafter, some examples of the present invention will be described to clarify the present invention more specifically. However, the present invention imposes some restrictions by the description of such examples. It goes without saying that you don't receive anything. Further, in addition to the following examples, the present invention may further include various changes and modifications based on the knowledge of those skilled in the art without departing from the spirit of the present invention, in addition to the above specific description. , Improvements and the like can be added.

Example 1 First, 3 liters of acetone was placed in a 5 liter beaker, and 600 liters were mixed with a table-top homomixer (manufactured by Tokushu Kika Kogyo).
While stirring at 0 rpm, 320 g of paste-like oil-containing lecithin (acetone-soluble matter = 37%) is allowed to flow down gradually little by little, and finely pulverized in acetone, whereby oil-containing lecithin particles are finely divided. A dispersed dispersion was produced. Next, after the obtained dispersion was allowed to stand, the supernatant was removed to obtain 1 liter of the dispersion.
By repeating this operation, a total of 10 liters of lecithin fine particle dispersion was prepared. This dispersion contains lecithin equivalent to about 2 kg (solid content: about 25%), the average particle size of the lecithin particles is about 100 μm, and the oil content in the lecithin particles is 10.5%.
%, And the oil concentration in the dispersion (acetone) was 4.26%.

On the other hand, as the extraction device, the same configuration as that shown in FIG. 1 is employed, 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, nine perforated plates were provided in this glass tube at a plate interval of 50 mm, and stirring blades were arranged in the space partitioned by the perforated plates in the same manner as in FIG. In addition, as the perforated plate, a plastic plate having a large number of holes of 5 mmφ (opening ratio 46%) was used.

With respect to such an extraction apparatus, the introduction position of the dispersion liquid from a glass tube having an inner diameter of 8 mm provided as a dispersion liquid supply port is adjusted, and the lecithin dispersion liquid is stirred through the glass tube. While maintaining the dispersion state, the mixture was fed by a metering pump to be introduced into a glass tube as an extraction column. Further, the insertion position of a glass tube having an inner diameter of 8 mm as an acetone supply port provided below the glass tube as an extraction column was adjusted, and the introduction position of acetone through the glass tube was adjusted. Then, acetone was supplied by a quantitative pump through the glass tube, and introduced into the glass tube as an extraction column. The extract was taken out as an overflow (overflow) of a glass tube as an extraction column, and the purified lecithin was taken out as a bottoms liquid (underflow) in a acetone-dispersed state using a metering pump. Then, such underflow liquid was filtered, further vacuum-dried at a temperature of 60 ° C., and collected as a purified lecithin powder.

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

[0024]

[Table 1]

Example 2 A continuous dispersing machine (Homomic Line Flow for Test, manufactured by Tokushu Kika Kogyo Co., Ltd.) was used, and acetone was continuously supplied thereto at a rate of 9.0 kg / min. Oil-containing lecithin (oil content 38%) is extruded and supplied from the nozzle at a speed of 1.5 kg / min, and the number of rotations is 5000 rpm.
By stirring at a rotational speed of, a dispersion in which oil-containing lecithin fine particles were dispersed was obtained. Then, 27 liters of the obtained dispersion liquid was allowed to stand, 17 liters of the supernatant was removed, and the remaining 10 liters were used as a lecithin dispersion liquid for continuous extraction. The solid content of the 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 concentration of the acetone dispersion medium was 5.03%.

On the other hand, as the extraction apparatus, an apparatus having the same configuration as in Example 1 except for the specifications, the number of stages, and the interval between the perforated plates was used. As the perforated plate, a plastic plate provided with a large number of holes of 8 mmφ (opening ratio 23%) was used, and the number of steps was 12 steps. Further, the interval between the perforated plates is 36 mm.
And

A continuous extraction operation of the above-mentioned lecithin dispersion liquid with acetone using such an extraction apparatus is performed under various extraction conditions (dispersion liquid flow rate, acetone flow rate, overflow liquid flow rate, underflow liquid flow rate), and the results are obtained. As shown in Table 2 below, as is clear from the results, purified lecithin having a very small content of acetone-soluble component of 3% or less was used.
It was easy to get 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 a continuous countercurrent system, its efficiency is low. It is significantly better than the conventional batch method and can save the solvent for extraction. In addition, lecithin having a high degree of purification can be continuously obtained, which has a great advantage in streamlining the process in terms of time, labor, and cost. In addition, the method of the present invention can be applied to the fractionation of lecithin having a high oil content and the purification of enzymatically treated / degraded lecithin.
It has advantages that can be applied.

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

[Brief description of the 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]

DESCRIPTION OF SYMBOLS 10 Extraction column 12 Perforated plate 14 Drive 16 Stirring blade 18 Dispersion liquid supply port 20 Extraction liquid outlet 22 Acetone supply port 24 Purified lecithin dispersion liquid outlet

Claims (1)

(57) [Claims] 1. A dispersion is prepared by finely dispersing a paste-like oil-containing lecithin as fine particles having an oil content of 16% or less in acetone, and then supplying the dispersion to the upper part of an extraction column. Acetone as an extraction solvent is supplied in a countercurrent manner from the lower part of the extraction column to extract oil from fine-particle lecithin descending in the extraction column, and purified lecithin particles are extracted from a lower outlet of the extraction column. A continuous method for purifying lecithin, wherein the method is taken out as an acetone dispersion.