JP2578549B2 - Method for producing low cholesterol oil and fat - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for separating and removing cholesterol from fats and oils containing cholesterol.

[0002]

BACKGROUND OF THE INVENTION It is well known that elevated blood cholesterol levels in humans are one of the causes of adult diseases such as arteriosclerosis and myocardial infarction.
For this reason, many people who have high blood cholesterol levels are actually restricted in their diet in order to suppress cholesterol intake.

[0003] On the other hand, cholesterol is contained in animal oils and fats and egg products in a large amount, and is an indispensable food in terms of its organoleptic appeal and nutritional aspects, and the intake of these foods is restricted. Cannot be denied that this is a major negative factor in actual dietary habits.

For this reason, many studies have hitherto been made for the purpose of removing cholesterol from animal fats. For example, a method of adsorbing and removing cholesterol with an adsorbent such as activated carbon, diatomaceous earth, and clay (Japanese Patent Application Laid-Open No. 61-1986)
136598) and a method of decomposing cholesterol contained in fats and oils by a microorganism of the genus Rhodococcus (Japanese Patent Laid-Open No. 1-222)
No. 9097). However, the method using adsorbents is inefficient in removing cholesterol compared to the amount used, and the method using microorganisms is problematic in terms of the safety of decomposed products. However, implementation on a factory scale was difficult.

In view of these problems of the prior art, the present inventors have conducted intensive studies with the aim of providing low-cholesterol fats safely and inexpensively. It has been found that cholesterol can be effectively removed by adding a step of adding fatty acid therein, and the present invention has already been filed as a "method for producing low cholesterol fats and oils" (JP-A-4-202599).

An object of the present invention is to provide
An object of the present invention is to provide a method for producing a low-cholesterol oil / fat capable of easily, easily and efficiently removing cholesterol from the oil / fat without lowering the oil yield, and having an extremely high oil yield.

[0007]

The present inventors have further studied a method for producing a low cholesterol fat and oil. (1) A free fatty acid was previously added to a cholesterol-containing fat and dispersed uniformly in an oil layer. After that, if the aqueous alkali solution is gradually added with stirring, the resulting oil droplets in the soap layer are atomized and homogenized, and as a result, cholesterol can be effectively removed. The free fatty acids to be added to the fats and oils are long-chain fatty acids having a carbon chain of 12 or more and are effective when the melting point is 60 ° C. or less; (2) Alkali metal salts of fatty acids in fats and oils containing cholesterol, Cholesterol can also be effectively removed by adding soap and mixing and stirring the resulting soap layer and cholesterol-containing oil / fat layer. (3) In either case of (1) or (2) above, the soap layer and the cholesterol-containing oil / fat layer are mixed and stirred. At that time, it was found that by lowering the temperature, cholesterol can be more effectively removed,
The present invention has been completed based on the latter finding (2).

Hereinafter, the method for producing the low cholesterol oil of the present invention will be described in detail.

First, the basic invention on which the present invention is based will be described.

The term "basic invention" as used herein means a method for producing a low-cholesterol fat or oil, which comprises the following steps: (1) adding a free fatty acid to a cholesterol-containing fat or oil and further adding an aqueous alkali solution; A first step of emulsifying the resulting alkali metal salt of fatty acid, ie, the soap and the oil layer, and (2) separating the mixture obtained in the first step into an oil layer and a soap layer, and separating the oil layer. A low-cholesterol fat or oil comprising a free fatty acid added to the cholesterol-containing fat or oil in advance in the first step, and sufficiently diffused into the oil layer, and then slowly stirred with stirring. An aqueous solution is added to produce an alkali metal salt of a fatty acid, a so-called soap, and at the same time uniformly mixed with the oil layer,
And a method of producing a low cholesterol fat (hereinafter referred to as "basic invention").

On the other hand, the method for producing a low-cholesterol oil or fat of the present invention is a method for producing a low-cholesterol oil or fat, which comprises the following steps: (a) adding an alkali metal salt of a fatty acid to a cholesterol-containing oil or fat; That is, a first step of adding, stirring, and emulsifying soap, and (b) a second step of separating the mixture obtained in the first step into an oil layer and a soap layer, and separating the oil layer A method for producing a low cholesterol fat (hereinafter, referred to as "the present invention").

A. Basic invention: As described above, the basic invention is a method for producing a low cholesterol oil and fat, and a soap produced in a cholesterol-containing oil and fat by adding and stirring a free fatty acid and an aqueous alkali solution to the cholesterol-containing oil and fat, It is characterized in that a low cholesterol fat is obtained by mixing and stirring with an oil layer. At that time, in order to quickly and sufficiently mix the soap layer and the oil layer, to separate the oil layer and improve the cholesterol removal efficiency, add a free fatty acid to the oil layer in advance, sufficiently mix and diffuse, and stir. While gradually adding an alkaline aqueous solution, the mixture is uniformly mixed with the oil layer while producing soap.

The cholesterol contained in the cholesterol-containing fat or oil, which is the starting material of the present invention, is more effective when it is in free form. If cholesterol fatty acid ester is present, it is converted into free form in advance with an enzyme such as cholesterol esterase. It is better to keep it.

In this case, the free fatty acids to be added include:
Free fatty acids having 10 or less carbon atoms have a poor cholesterol removal rate, and fatty acids having a high melting point, such as palmitic acid and stearic acid, are more likely to be taken up by the alkali metal salts of the oil, and must be treated at high temperatures. In order to reduce cholesterol efficiently, it is often undesirable. Therefore, as the fatty acid to be added in the basic invention, lauric acid, myristic acid, oleic acid, fatty acids that are liquid at room temperature having 12 or more carbon atoms such as linoleic acid are desirable,
Oleic acid is particularly preferred in view of simplicity of processing in the process, oil yield, cholesterol reduction efficiency, price and the like.

The amount of the fatty acid to be added to the oil and the concentration and amount of the aqueous alkali solution may be such that the free fatty acid added can be removed as an alkali metal salt within a range where the generated soap layer and oil layer can be separated. Preferably, the fatty acid is 0.5 to 10% by weight of the oil layer and the aqueous alkaline solution is 5 to 40% by weight.
It is desirable to add an aqueous solution having a concentration of about 50% by weight in an amount within 50% by weight of the oil layer.

In this reaction, when an alkali metal salt of a fatty acid is used as a surfactant and the fat or oil is taken into the micelles as o / w type emulsification, the cholesterol in the fat or oil is also similar to the alkali metal salt of the fatty acid. The cholesterol plays a role as a surfactant, and is caused by active transfer of cholesterol into micelles. Therefore, it is considered that low cholesterol fats and oils are obtained.

Further, in order to improve the oil yield and reduce cholesterol efficiently, it is desirable to homogenize the micelles in order to reduce the volume inside the micelles and increase the surface area.

Further, the stirring condition is preferably as low as possible as long as the oil layer and the soap layer can be separated from the viewpoint of the reduction of cholesterol. Preferably, it is short.

The stirrer used for stirring is not particularly limited.
It is better to be able to quickly mix with the oil layer and reduce the size of the oil droplets to be taken in and to have the ability to homogenize it.However, if only cholesterol is to be removed, the soap will be produced with gentle stirring using a propeller etc. Then, after the soap is mixed with the oil layer by stirring as it is, it is only necessary to separate the oil layer.

In the actual oil refining process, the process of removing free fatty acids by adding an aqueous alkali solution, that is, the deoxidizing process is carried out at 70 to 80 ° C. When taking in, add the free fatty acid to the oil at a high temperature, add an aqueous alkali solution while stirring to make a soap, gradually cool while stirring, and when the temperature drops to some extent, the oil layer and the soap layer It is desirable to separate quickly. Further, in this case, the cholesterol removal rate is somewhat reduced, but it is possible to perform the treatment at a high temperature, and the oil yield is slightly reduced.
It is also possible to perform the treatment after the temperature is lowered in advance.

Next, the mixture obtained by stirring and emulsifying the soap layer and the oil layer in this manner is separated and fractionated into an oil layer and a soap layer.

In this case, as a separation / separation method, a general filter, a centrifuge, or the like can be used. In consideration of the actual fat / oil refining process, preferably, the centrifuge is used as it is. good.

The oil layer separated and recovered in this way is a low cholesterol oil and fat. If necessary, for example, an activated clay used in an actual oil and fat refining process may be used. Through the decolorizing step described above and the deodorizing step of performing steam distillation with a high-temperature heated oil and fat under reduced pressure, it can be used as an edible oil and fat without any problem.

B. The present invention: As described above, in the basic invention, a free fatty acid and an aqueous alkali solution are added to a cholesterol-containing fat and oil and stirred,
Cholesterol was removed from the cholesterol-containing fats and oils by mixing and stirring the soap produced in the cholesterol-containing fats and oils with the oil layer. In contrast, in the present invention, an alkali metal salt of a fatty acid, i.e., a soap, is added to a cholesterol-containing fat and oil, and the soap layer and the cholesterol-containing fat layer are mixed and stirred, thereby obtaining cholesterol in the same manner as in the basic invention. Can be removed.

In this case, the alkali metal salt of the fatty acid to be added is not particularly limited. For example, a hydrated soapstock such as a sodium salt of a fatty acid by-produced in deoxidizing and refining fats and oils may be used. Absent.

When the soap is directly added to the cholesterol-containing oil or fat as in the present invention, if the soap layer contains a sufficient amount of the oil or fat, a low cholesterol oil or fat can be obtained without substantially reducing the oil yield. be able to.

The stirring may be carried out as long as the fats and oils and the alkali metal salt of the fatty acid to be added are sufficiently mixed, and the temperature during the stirring may be such that the fats and oils are kept in a liquid state. It is preferable to set the temperature to a low temperature as long as it can be separated.

It is to be noted that, after uniformly stirring and mixing an alkali metal salt of a fatty acid, so-called soap, with the oil, the stirring is stopped immediately without excessive stirring and the oil layer is separated, whereby cholesterol can be efficiently removed. Can be removed.
Taking into account the oil yield, cholesterol removal rate, etc., gentle stirring at a low temperature for a short time is effective.

Further, as the stirrer used for stirring, especially in the case of the present invention in which soap is added to cholesterol-containing fats and oils, a stirrer having the ability to reduce the size of emulsified particles and to mix quickly is preferable. good.

Further, it is effective to lower the temperature of the oil layer to reduce the solubility of cholesterol in the oil layer.

The amount of the soap to be added may be an amount within such a range that the aqueous layer including the soap layer and the oil layer can be separated after stirring and mixing.

In order to reduce the cholesterol content in fats and oils, it is only necessary to mix the cholesterol-containing fats and oils with an alkali metal salt of a fatty acid which already contains water and fats and shake lightly.

Next, the mixture obtained by stirring and emulsifying the soap layer and the oil layer in this way is separated and fractionated into an oil layer and a soap layer.
The sorting may be performed basically in the same manner as in the basic invention described above.

On the other hand, the soap layer thus collected and recovered can be used again in the present invention, and is added to a cholesterol-containing fat or oil, and the same operation is repeated to produce a low cholesterol fat or oil. Can be.
That is, the soap used in the present invention may contain cholesterol in oils and fats contained in the soap layer in advance, as long as the soap layer does not shift from the soap layer to the oil layer.

In addition, the soap layer repeatedly used contains a very large amount of cholesterol and can be sufficiently used as a cholesterol extraction source. For example,
To the soap layer repeatedly used, an organic solvent such as ethanol, acetone, or isopropanol is added to separate / separate the soap-containing oil and fat. Thus, cholesterol can be separated and purified by a cholesterol extraction method by forming crystals, adsorption, and complex formation. At this time, the organic solvent used has low polarity,
For example, the above-mentioned ethanol and acetone which are soluble in water are more preferable than those which are insoluble in water, such as hexane and ether.

[0036]

EXAMPLES Hereinafter, a method for producing a low-cholesterol oil and fat will be described in more detail based on Comparative Examples and Examples.

The cholesterol-containing oil used in the following comparative examples refers to corn oil or rapeseed oil to which chicken egg yolk has been added, and 15,000 with a homogenizer, unless otherwise specified.
It refers to an oil containing cholesterol, which is obtained by centrifuging at 5,000 rpm for 5 minutes after vigorously stirring at rpm and separating into an egg yolk layer and an oil layer.

Comparative Example 1: (Addition: Fatty Acid + Alkaline Aqueous Solution) ( Effect of Fatty Acid and Stirring Temperature) ( Stirrer : Propeller) Cholesterol-Containing Oil (Cholesterol 4.09 mg / g) 20
To 0 g, 8 g each of oleic acid, stearic acid and caprylic acid are added, and for those containing oleic acid and stearic acid, 10 ml of 20% sodium hydroxide solution is added. For those containing caprylic acid, After adding 20 ml of a 20% sodium hydroxide solution, the mixture was stirred with a propeller at 500 rpm for 15 minutes. The stirring temperature is (1) 60-70 ° C for 15 minutes,
(2) 70 ° C for 5 minutes for the first 5 minutes
To 10 ° C, last less than 10 ° C for 5 minutes,
(3) The temperature was maintained at 10 ° C. or less for 15 minutes. After completion of the stirring, the mixture was centrifuged at 5,000 rpm for 5 minutes, and the yield of the oil layer and the cholesterol content were measured. The results are shown in Table 1.

[0039]

[Table 1]

The experiment was not carried out because stearic acid is solid at 10 ° C. and does not become an alkali metal salt of a fatty acid even when an aqueous alkali solution is added.

As is clear from this table, the oil yield and cholesterol removal rate of oleic acid, stearic acid, and caprylic acid differ greatly, and the difference depending on the temperature is observed as the alkali metal salt of fatty acid. It is considered that the lipophilicity and affinity for cholesterol differ depending on the type and temperature of the fatty acid.

The effect of removing cholesterol was high when stearic acid or oleic acid having a long carbon chain was used, and when caprylic acid was used, the effect was low. In addition, the oil yield is better treated at 60-70 ° C,
Lower temperatures are better for cholesterol removal. Also, when oleic acid is used, stirring is started at 60 to 70 ° C to generate soap, and when the stirring is finished, the temperature is lowered to 10 ° C or less. It was effective.

Comparative Example 2: (Addition: Fatty Acid + Alkaline Aqueous Solution) ( Effects of Fatty Acid Type and Stirring Temperature) ( Stirrer : Homomixer ) Cholesterol-Containing Fat 200 g (Cholesterol 4.46 mg)
/ G) with propionic acid, caprylic acid, oleic acid,
8 g of each was added, and 40 ml, 20 ml and 10 ml of a 20% aqueous sodium hydroxide solution were added, respectively.
(1) 60-70 ° C, 10,000 rpm, stirred for 2 minutes,
(2) 20-30 ° C, 10,000 rpm, stirred for 2 minutes,
(3) Stirring was performed at 10,000 ° C. or lower at 10 ° C. for 2 minutes. After completion of the stirring, the mixture was centrifuged at 5,000 rpm for 5 minutes, and the yield of the oil layer and the cholesterol content were measured. The results are shown in Table 2.

[0044]

[Table 2]

Based on the results of Comparative Example 1, propionic acid and caprylic acid were used as free fatty acids having a short carbon chain, and oleic acid was used as a long fatty acid. C), room temperature (20-30 ° C), and low temperature (10 ° C or less). Also, stirring
The time was reduced to 2 minutes at 10,000 rpm. The results were almost the same as in Comparative Example 1, and the treatment at room temperature and low temperature when oleic acid was used was most effective for efficient removal of cholesterol.

Comparative Example 3: (Addition: Fatty Acid + Alkaline Aqueous Solution) ( Effect of Fatty Acid Type and Stirring Temperature) ( Stirrer : Propeller) Cholesterol-Containing Oil 200 g (Cholesterol 4.17 mg)
/ G), lauric acid, myristic acid, palmitic acid,
8g each of stearic acid, oleic acid and erucic acid
14% each of 20% aqueous sodium hydroxide solution,
12 ml, 11 ml, 10 ml, 10 ml, and 8.3 ml were added, and the mixture was stirred with a propeller at (1) 60 to 70 ° C., 500 rpm for 15 minutes,
(2) After stirring at 500 rpm, 70 ° C for 5 minutes, 10 ° C for 5 minutes
, And stirred at 10 ° C. or lower for an additional 5 minutes. After stirring, 5,000 rp
After centrifugation for 5 minutes, the yield of the oil layer and the cholesterol content were measured. Table 3 shows the results.

[0047]

[Table 3]

It has been clarified by experiments so far that free fatty acids having 10 or more carbon atoms have little effect on the removal of cholesterol even if an alkali metal salt thereof is produced. Then, I examined what kind of difference there is. As is clear from Table 3, it can be seen that when the number of carbon atoms is 12 or more, all of them have a cholesterol removing effect, but when palmitic acid and stearic acid have a high melting point, the oil yield decreases when the temperature is lowered. It tends to worsen and the cholesterol removal effect also tends to decrease. On the other hand, low melting point lauric acid, myristic acid, erucic acid,
It is recognized that oleic acid, which is liquid at normal temperature, has a good yield and is excellent in removing cholesterol.

Comparative Example 4: (Addition: Fatty Acid + Alkaline Aqueous Solution) ( Effect of Stirring Temperature) ( Stirrer : Propeller ) To 200 g of purified fish oil (2.65 mg / g cholesterol), 8 g of oleic acid or linoleic acid was added. Add 10 ml of a 20% aqueous sodium hydroxide solution and use a propeller to (1) 60-70 ° C,
500 rpm, stirring for 5 minutes, (2) 500 rpm, 70 ° C, 1
After stirring for 5 minutes, quenched and cooled to 10 ° C or less for a total of 5 minutes, (3) Stirred at 20-30 ° C, 500 rpm for 5 minutes, (4) Stirred for 10 minutes or less, 500 rpm, 5 minutes What did
4 treatments were performed. After stirring, 5,000 rpm, 5 minutes
After centrifugation, the oil layer yield and cholesterol content were measured. Table 4 shows the results.

[0050]

[Table 4]

A similar experiment was conducted using linoleic acid having the same carbon number as oleic acid and being liquid at room temperature, and the effect was confirmed. As is clear from Table 4, even with linoleic acid,
The same effect as that of oleic acid was confirmed.

Comparative Example 5: (After adding an aqueous alkali solution,
If the addition of acid) cholesterol containing oil 200 g (cholesterol 4.00mg
/ G), 10 ml of a 20% sodium hydroxide solution is added,
(1) While stirring at 10,000 rpm at 20 to 30 ° C. with a homogenizer, 8 g of oleic acid was added and stirring was further continued for 2 minutes. (2) While stirring at 20 to 30 ° C. and 500 rpm with a propeller, Oleic acid (8 g) was added, and stirring was further continued for 5 minutes. After stirring, 5,000 rp
After centrifugation for 5 minutes, the yield of the oil layer and the cholesterol content were measured. Table 5 shows the results.

[0053]

[Table 5]

As is clear from the results in this table, if an alkaline aqueous solution is added to the oil layer, and then a free fatty acid is added to form a soap, in order to perform a sufficiently uniform and efficient stirring, It can be seen that strong stirring must be performed. Further, it can be seen that when o / w type emulsification occurs, oil is easily taken in, the oil yield is reduced, and the cholesterol removal rate is reduced.

Comparative Example 6: (Addition: Fatty Acid + Alkaline Aqueous Solution) ( Effect of Stirring Temperature) ( Stirrer : Propeller) 200 g of Cholesterol-Containing Oil (Cholesterol: 4.12 mg)
/ G), 8 g of oleic acid, 10 ml of a 20% aqueous sodium hydroxide solution, and a propeller at 10 ° C or lower and 500 rpm for 2 minutes, 4 minutes, 6 minutes, 8 minutes and 10 minutes, respectively.
For 15 minutes. After completion of the stirring, the mixture was centrifuged at 5,000 rpm for 5 minutes, and the yield of the oil layer and the cholesterol content were measured. Table 6 shows the results.

[0056]

[Table 6]

Comparative Example 7: (Addition: Fatty Acid + Alkaline Aqueous Solution) ( Effect of Stirring Temperature) ( Stirrer : Propeller) Cholesterol-Containing Oil 200 g (Cholesterol 4.00 mg)
/ G), 8 g of oleic acid was added thereto, and 10 ml of a 20% aqueous sodium hydroxide solution was further added.
2 minutes, 4 minutes, 6 minutes, 8 minutes, 10 minutes
For 15 minutes. After completion of the stirring, the mixture was centrifuged at 5,000 rpm for 5 minutes, and the yield of the oil layer and the cholesterol content were measured. Table 7 shows the results.

[0058]

[Table 7]

According to Comparative Examples 6 and 7, it can be seen that soap is produced in cholesterol-containing fats and oils at a high or low temperature and the cholesterol-removing effect is obtained in a short time by stirring. Higher temperatures yield higher oil yields, but lower cholesterol removal rates are better. Therefore, if the main focus is on the removal of cholesterol, it can be said that the low-temperature treatment is superior to the high-temperature treatment. However, in the low-temperature treatment, the longer the stirring time, the more the oil yield tends to be reduced. Therefore, the shorter the stirring time at low temperature, the better.

Comparative Example 8: (Addition: fatty acid + alkaline aqueous solution)
Liquid) Purified fish oil (cholesterol content 2.29mg / g) 200g,
Add 8 g of oleic acid, and use a homomixer to make 10,000 rp.
While stirring at m 2, 10 ml of a 20% sodium hydroxide solution was added. After stirring at 25 ° C. for 1 minute, the resulting mixture was centrifuged at 5,000 rpm for 5 minutes to separate an oil layer and a soap layer. The yield and the cholesterol content of the separated oil layer were measured.

Further, 50 g of the separated soap layer was again
Added to 200 g of purified fish oil (cholesterol content 2.29 mg / g), and homomixed at 10,000 rpm for 1 minute at 25 ° C.
After stirring, the resulting mixture was centrifuged at 5,000 rpm for 5 minutes to separate an oil layer and a soap layer. In addition,
The yield and cholesterol content of the separated oil layer were measured. The results are shown in Table 8 below.

[0062]

[Table 8]

Comparative Example 9 (Addition: Soap) 8 g of oleic acid was added to 200 g of corn oil, 10 ml of 20% sodium hydroxide was added with stirring, and the mixture was stirred with a homomixer at 10,000 rpm for 1 minute. Then 5,000r
Centrifugation was performed at pm for 5 minutes to separate a soap layer.
The moisture content and the fat content of this soap layer are, respectively,
19.2% and 30.3%. 50 g of this soap layer is applied to 200 g of cholesterol-containing fats and oils (cholesterol 4.13 mg /
g) and stirred with a homomixer at 10,000 rpm for 1 minute. After centrifugation, the oil layer yield and cholesterol content were measured. As a control, 200 g of cholesterol-containing oil (cholesterol 4.13 mg / g) was added to oleic acid 8
g, 10 ml of 20% sodium hydroxide, and the mixture was stirred with a homomixer at 10,000 rpm at 25 ° C. for 1 minute. After centrifugation, the yield of the oil layer and the cholesterol content were measured and compared. The results are shown in Table 9 below.

[0064]

[Table 9]

Comparative Example 10: (When soap was added, fatty acid +
Comparison with addition of aqueous alkali solution) 100 g of rapeseed oil is heated to 120 ° C., and 50 ml of a 50% sodium hydroxide solution is added. Boiling at 120-130 ° C for 10 minutes gives a viscous, translucent liquid.

After leaving to cool for a while, salting out with a saturated saline solution produces a soap layer in the upper layer and an aqueous layer in the lower layer. This soap had a solid content of 80%, an oil content of 4%, and a water content of 16%.

50 g of this soap was added to 200 g of a cholesterol-containing oil (cholesterol 4.03 mg / g), and the mixture was stirred with a homomixer at 10,000 rpm at 25 ° C. for 1 minute. After centrifugation, the yield of the oil layer and the cholesterol content Was measured.

As a control, oleic acid 8 was added to 200 g of cholesterol-containing oil (cholesterol 4.03 mg / g).
g, 10 ml of 20% sodium hydroxide, and the mixture was stirred with a homomixer at 10,000 rpm at 25 ° C. for 1 minute. After centrifugation, the yield of the oil layer and the cholesterol content were measured and compared. Table 10 shows the results.

[0069]

[Table 10]

As is apparent from the results of Comparative Examples 8 to 10, not only the soap was formed in the cholesterol-containing fat and oil, but also the soap was previously added to the cholesterol-containing fat and the mixture was stirred and separated. By doing so, a low cholesterol fat can be obtained. Also, if oil is already contained in the soap, it is possible to remove only cholesterol with almost no loss of oil yield, and even if the oil layer contained in the soap layer contains cholesterol, its effect will be reduced. It is clear that there is.

[0071] was dissolved example butter, oil layer the cholesterol content 1.94 mg / g
200 g were obtained. Add oleic acid to corn oil,
Soap prepared by adding sodium hydroxide (oil content 30.3
40% by weight) and 10,000 rpm,
After stirring for 1 minute, centrifuge at 5,000 rpm for 5 minutes,
195 g of an oil layer was obtained. The cholesterol content of this oil layer was 1.06 mg / g.

[0072]

According to the basic invention, the free fatty acid is added to the oil layer in advance, sufficiently mixed and diffused, and the aqueous alkali solution is gradually added with stirring to uniformly mix the oil layer with the oil layer while producing soap. . On the other hand, in the present invention, an alkali metal salt of a fatty acid, that is, a soap, is added to a cholesterol-containing fat or oil in advance, and the resulting mixture is stirred. An excellent method for removing cholesterol from fats and oils can be provided.

Further, in the present invention, the separated and recovered oil layer is a low cholesterol oil and fat, and can be used as a general edible oil and fat. In the present invention, it can be used repeatedly, added to cholesterol-containing fats and oils, and by repeating the same operation, low-cholesterol fats and oils can be produced, so there is no problem in terms of cost and safety, and it can be carried out on a factory scale. It becomes possible.

The soap layer repeatedly used contains a very large amount of cholesterol and can be sufficiently used as an extraction source of cholesterol, and cholesterol can be separated and purified by a conventionally known cholesterol extraction method. It becomes possible.

Claims (2)

(57) [Claims] 1. A method for producing a low-cholesterol oil or fat, comprising the following steps: (a) adding an alkali metal salt of a fatty acid, ie, a soap, to a cholesterol-containing oil or fat, stirring and emulsifying, And (b) a second step of separating the mixture obtained in the first step into an oil layer and a soap layer, and separating the oil layer. 2. The method according to claim 1, wherein the alkali metal salt of a fatty acid contains cholesterol.