JPH04168198A - Method for removing cholesterol in animal oil and fat and animal oil and fat reduced in cholesterol - Google Patents

Abstract

PURPOSE:To remove cholesterol in animal oil and fat in high efficiency by blending liquefied animal oil and fat with water and cyclodextrin at a specific ratio and mixing and stirring the blend at a specific temperature to clathrate the cholesterol in the cyclodextrin and then separating a water layer therefrom. CONSTITUTION:(A) Liquefied animal oil and fat consisting anhydrous or water- containing batter, milk fat, pig fat, fish oil, etc., is blended with (B) water having an amount being >=0.3 in wt. ratio to the component A and (C) cyclodextrin having an amount giving weight ratio (>=0.3) to water corresponding to supersaturated state while stirring to clathrate cholesterol in cyclodextrin and then the resultant clathrate compound is separated and removed by separating a water layer to remove the cholesterol in animal oil and fat.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention uses cyclodextrin to separate and remove cholesterol contained in animal fats and oils such as anhydrous or water-containing butter, milk fat, pig intestine, beef tallow, and fish oil. The purpose of this method is to efficiently remove (remove) cholesterol from the animal fat, which is one of the reasons why animal fat is avoided due to fear of adult diseases. To provide animal fats and oils with good productivity and at low cost, from which cholesterol, which is a common substance, has been almost completely removed.

[Prior Art] It is well known that cyclodextrins form clathrate compounds with organic compounds such as phenols, and methods for clathrating various substances have been attempted.

A method of removing cholesterol from animal fats and oils using this principle has been proposed. This method involves liquefying a fatty substance of animal origin containing cholesterol, contacting the liquefied fatty substance with cyclodextrin powder, and exposing the contact material to a temperature between the melting temperature of the fatty substance and 80°C for 30 minutes.
A complex is formed between cholesterol and cyclodextrin by stirring for 10 minutes to 10 hours, then the fatty material containing this complex is introduced into water, the complex is washed out from the fatty material with water, and the aqueous phase of the washing solution is then washed out. This is a method for removing cholesterol contained in fatty substances of animal origin, which consists of removing the complex by separation (Japanese Patent Application Laid-Open No. 63-41595).

[Problems to be Solved by the Invention] However, in the above method, cyclodextrin is directly mixed into a liquefied fatty substance, reacted with the cholesterol contained therein, and then the clathrate compound is separated and removed with water. In order to bring the cyclodextrin into sufficient contact with the fatty substance, the fatty substance is heated and liquefied, powdered cyclodextrin is added to the liquefied fatty substance, and the mixture is heated and stirred for a long time. With this method, the maximum cholesterol removal rate is as low as 33%, and even if this continuous operation is repeated three times, only 41% can be removed. However, it is necessary to repeat the above-mentioned operation many times in succession, resulting in extremely poor productivity and disadvantageous economics.

[Means for Solving the Problems 1] In order to solve the problems of the conventional method, the present inventors have conducted various studies and found that when bringing animal fat and fat into contact with cyclodextrin, the two are brought into contact in the presence of water. Moreover, if cyclodextrin is used in an amount supersaturated with respect to water, that is, in the presence of cyclodextrin in a suspended state, and the mixture of liquefied animal fat, water, and cyclodextrin is stirred, - The present invention has been completed based on the discovery that the cholesterol contained in the fatty substances can be removed with extremely high removal efficiency of 99% or more in just one operation.

Specifically, the method for removing cholesterol from animal fats and oils of the present invention uses liquefied animal fats and oils in which the weight ratio of water to the animal fats and oils (as anhydride) is 0.3 or more, preferably 0.
．． 4 or more, and the weight ratio of cyclodextrin to water is 0.02 or more, preferably 0.04.
Blending with cyclodextrin in an amount such that the above supersaturation state is achieved, and mixing at a temperature above the melting temperature of the animal fat,
The method is characterized in that the cholesterol in the animal oil and fat is included in cyclodextrin by stirring, and then the clathrate compound is separated and removed by separating the aqueous layer.

Furthermore, the present invention aims to provide animal fats and oils with reduced cholesterol obtained by the method.

In the present invention, animal fats and oils used as raw materials include fatty substances such as anhydrous or water-containing butter, milk fat, pig intestine, beef tallow, and fish oil. When these fatty substances are liquid at room temperature, they are used as they are, and when they are solid, they are heated and used as a liquid.

Cyclodextrin, which is used to clathrate cholesterol contained in these fatty substances, is made by adding Bacillus macerans to starch or dextrin.
It is a cyclic dextrin obtained by the action of a type of amylase produced by A. Ru.

It is thought that this internal hydrophobic structure binds with a portion of the hydrophobic steroid nucleus of cholesterol to form an inclusion compound.

α-2β-1γ-cyclodextrin consists of 6.7.8 glucose structural units, each with an inner diameter of 5.
．． 7, 7.5, 95 people. Among these, β-cyclodextrin has high inclusion specificity, probably because its inner diameter matches the size of a portion of the steroid nucleus.

In the present invention, β-cyclodextrin and γ-cyclodextrin, which have relatively high cholesterol inclusion specificity, can be preferably used, and β-cyclodextrin is particularly preferred from the viewpoint of cholesterol removal efficiency and economical efficiency.

When incorporating cholesterol in animal fats and oils into cyclodextrin, the blending ratio of animal fats and oils to cyclodextrin is determined by the blending ratio of animal fats and oils to water, the blending ratio of water to cyclodextrin, etc. However, in view of the balance between cholesterol removal effect and economical efficiency, it is usually appropriate to blend cyclodextrin in a weight ratio of 0.03 to 0.5 to animal oil (as anhydride), particularly 0.05. It is preferably within the range of 0.2 to 0.2.

The most important thing in the present invention is that when bringing liquefied animal fat and fat into contact with cyclodextrin in the presence of water, the amount of water such that the weight ratio of water to the animal fat (as anhydrous) is 0.3 or more is When treated by blending water with cyclodextrin in an amount such that the weight ratio of cyclodextrin to water becomes supersaturated at 0.02 or more, the cholesterol inclusion ability of cyclodextrin increases and the cholesterol removal rate increases. The significant improvement in
This is a new finding that the inventors of the present invention have discovered phenomenologically for the first time through experiments, and although the reason for this is not yet clear, it is presumed to be due to the following reasons.

That is, in a mixed system of water and oil, cyclodextrin forms the above-mentioned amphipathic structure in the water layer,
It is thought that it comes into contact with cholesterol dissolved in the oil layer to form an clathrate compound. This reaction is considered to be in equilibrium at the oil/water interface. Therefore, in order to completely remove cholesterol from the oil layer, a cyclodextrin inclusion compound that includes cholesterol and becomes insoluble in water needs to precipitate in the water layer. This is believed to be the reason why cyclodextrin must be present in a suspended supersaturated state with a weight ratio of 0.02 or more to water.

On the other hand, when cyclodextrin is present directly in the oil layer,
Since the surrounding environment is all hydrophobic, the above-mentioned amphiphilic structure is not formed, and a reverse micelle-like association is forced to form. It is thought that such a structure becomes difficult to include cholesterol.

Therefore, in order for cyclodextrin to assume an appropriate amphipathic structure without forming reverse micelle-like associations with fats and oils, a sufficient amount of water is required to form such an amphipathic structure. More specifically, it is determined that the presence of water in a weight ratio of 0.3 or more to animal oil (as anhydrous) is necessary. Thus, in order for cyclodextrin to efficiently remove cholesterol from an oil layer, it is necessary to use an amount of cyclodextrin such that the weight ratio of cyclodextrin to water is 0.02 or more, which is a supersaturation state, and a ratio of water to animal oil (as anhydrous). It is necessary that water be present in an amount such that the weight ratio is 0.3 or more.

At this time, the weight ratio of cyclodextrin to water is 0.
If it is lower than 02, the amount of suspended cyclodextrin decreases, resulting in insufficient cholesterol inclusion ability, and the efficiency of removing cholesterol from animal fats and oils decreases. On the other hand, if the weight ratio of cyclodextrin to water is too high (usually around 0.5) to the extent that an aqueous suspension is no longer formed, precipitation of the clathrates in the aqueous layer as described above is prevented. This not only reduces the cholesterol inclusion function of cyclodextrin, but also increases the amount of cyclodextrin used, which is economically disadvantageous.

Furthermore, if the weight ratio of water to animal oil (as anhydride) is lower than 0.3, the above-mentioned amphipathic structure will not be formed sufficiently, and the cholesterol inclusion function of cyclodextrin will decrease. Cholesterol removal efficiency decreases.

On the other hand, if the weight ratio of water to animal oil (anhydrous) is too high (usually about 10), the clathrate compound of cyclodextrin and cholesterol will not be sufficiently precipitated; Since a large amount of cyclodextrin is required for this purpose, it is economically disadvantageous.

To mix animal fat, water, and cyclodextrin, water may be added to the liquefied animal fat and cyclodextrin may be added thereto, or the cyclodextrin may be suspended in water in advance and this suspension may be liquefied. Methods such as adding it to animal fats and oils can be adopted.

The mixture of animal fat, water, and cyclodextrin is heated as necessary during stirring. Heating may be carried out at a temperature at which the animal fat or oil becomes liquid.

The stirring time of the mixture is not particularly limited, as long as it is sufficient for cholesterol to be included. Most of the chemical reactions of fats and oils are carried out under non-oxidizing conditions, but in the case of the present invention, stirring and the like for inclusion treatment can be carried out in the atmosphere.

The mixture of animal oil and fat and a cyclodextrin aqueous suspension containing cholesterol in the animal oil is then prepared by adding water and stirring, or by pouring the mixture into water and stirring, as necessary. It is separated into an oil layer consisting of fats and oils and an aqueous layer containing a cyclodextrin clathrate compound.

Next, by separating this two-layered mixture using a commonly used physical method such as centrifugation, a fatty substance from which cholesterol has been removed with extremely high removal efficiency can be obtained.

[Effects of the Invention] According to the present invention, liquefied animal fat, a specific amount of water relative to the animal fat (as anhydride), and an amount of cyclodextrin that is supersaturated with respect to the water are combined. By using a simple method of blending and processing, up to 99% of cholesterol in fatty substances can be removed in just one operation.
Since cholesterol can be removed with extremely high removal efficiency, fatty substances from which cholesterol has been almost completely removed can be provided with good productivity and at low cost.

Note that the fatty substance from which cholesterol has been removed according to the present invention retains the flavor of animal fat without impairing the original flavor of the fatty substance.

[Example] Next, the present invention will be explained with reference to Examples, but the present invention is not limited to these.

Example 1 10g of commercially available butter was heated and water removed by centrifugation (hereinafter referred to as anhydrous butter), and water was added at a water/oil weight ratio of 0.2, [1,3, (1,4 ,1,0,3,0
, 5,0,1O10, and heated to 45°C. On the other hand, the weight ratio to water is 0.01.0.
02.0.03.0.04.0.10.0.3(+,0
．． β-cyclodextrin (Wako Pure Chemical Industries, Ltd. Knee Grade Reagent) was added to give a concentration of 50%, and the mixture was stirred at 45° C. for 60 minutes. After centrifugation, a certain amount of the recovered oil layer was collected, and the cholesterol content was determined by gas chromatography according to the fat standard analysis method. Stigmasterol was used as an internal standard. Using the same treatment without adding β-cyclodextrin as a control, the cholesterol removal rate was calculated using the following formula.

Removal rate (%) = 100--X 100 In the above formula: A: Amount of cholesterol in the oil layer of the control (per unit weight) B: Amount of cholesterol in the oil layer of the treated sample (per unit weight) The results are shown in Table 1. show.

Table 1 Example 2 10 g of heated and melted anhydrous butter and β-cyclodextrin aqueous suspension (1 g of β-cyclodextrin was mixed with 10 g of water
Example 1
After shaking and stirring as shown in , the amount of cholesterol was determined and the removal rate was determined.

By this operation, 95% of the cholesterol in anhydrous butter is
．． 2% was removed.

Example 3 Add 10 m of water to 10 g of commercially available butter at 45°C.
It was heated to Add 1g of β-cyclodextrin,
After stirring at 5° C. for 60 minutes at 10° C., the amount of cholesterol was determined as described in Example 1 to determine the removal rate.

The results were as shown in Table-2.

Table 2 Example 4 10 m 12 of water was added to 10 g of commercially available genuine lard and heated to 45°C. In this, β-cyclodextrin 1
After stirring at 45°C for 60 minutes, the oil layer was separated by centrifugation. The amount of cholesterol in the obtained oil was determined in the same manner as in Example 1 to determine the removal rate.

The results are shown in Table 4.

Example 5 10 mfl of water per 10 g of refined sardine oil (manufactured by Ueda Oil Co., Ltd.)
was added and heated to 45°C. 1.2 g of β-cyclodextrin was added thereto, and after stirring at 30°C for 60 minutes, 40 m 12 of water was added and heated, and the oil layer was collected by centrifugation. The amount of cholesterol in the obtained oil was determined in the same manner as in Example 1 to determine the removal rate.

The results are shown in Table 4.

Example 6 1.2 g of β-cyclodextrin was added to 20 g of commercially available cream (water content 50%), stirred with shaking at 30° C. for 60 minutes, then warmed, and an oil layer was collected by centrifugation.

The amount of cholesterol in the obtained oil was determined in the same manner as in Example 1 to determine the removal rate.

The results are shown in Table 4.

Table 4 The numbers in parentheses in the main column of Example 6 indicate the water content in the cream.

Claims (6)

[Claims] (1) Liquefied animal fat, water in an amount such that the weight ratio of water to the animal fat (as anhydrous) is 0.3 or more, and the weight ratio of cyclodextrin to water is 0.02.
Blending with cyclodextrin in an amount such that the above supersaturation state is achieved, and mixing at a temperature above the melting temperature of the animal fat,
1. A method for removing cholesterol from animal fats and oils, which comprises stirring to include the cholesterol in the animal fats and oils in cyclodextrin, and then separating and removing the clathrate by separating an aqueous layer. (2) The method according to item (1), wherein the animal fat or oil is anhydrous or water-containing butter, milk fat, lard, beef tallow, or fish oil. (3) The method according to claim (1), wherein the cyclodextrin is β-cyclodextrin. (4) Liquefied animal fat, water in an amount such that the weight ratio of water to the animal fat (as anhydrous) is 0.3 or more, and the weight ratio of cyclodextrin to water is 0.02.
Blending with cyclodextrin in an amount such that the above supersaturation state is achieved, and mixing at a temperature above the melting temperature of the animal fat,
An animal fat and oil with reduced cholesterol obtained by stirring to include cholesterol in the animal fat in cyclodextrin, and then separating and removing the clathrate by separating an aqueous layer. (5) The animal fat or oil according to claim (4), wherein the animal fat or oil is anhydrous or water-containing butter, milk fat, lard, beef tallow, or fish oil. (6) The animal fat and oil according to claim (4), wherein the cyclodextrin is β-cyclodextrin.