JP5550282B2 - Process for producing fats and oils with high diacylglycerol content - Google Patents

Description

  The present invention relates to a method for producing fats and oils with a high diacylglycerol content.

Oils and fats containing diacylglycerol at a high concentration are widely used as edible oils because they have physiological actions such as body fat burning action. The production of diacylglycerol is generally performed by a glycerolysis reaction between glycerin and fat or fat or a method by esterification of glycerin and fatty acid (see, for example, Patent Documents 1 to 3), but monoglyceride and fat are esterified. There is also an exchange reaction method (see Patent Document 4).
In addition, there is a method in which a fatty acid used in an esterification reaction is produced by hydrolyzing a raw oil and fat in combination with a high-pressure decomposition method and an enzymatic decomposition method, and then the fatty acid and glycerin are esterified (see Patent Document 5). ).
These production methods are roughly classified into a chemical method using an alkali catalyst or the like and an enzyme method using an enzyme such as lipase.

Japanese Examined Patent Publication No. 6-65310 Japanese Patent Publication No. 6-65311 JP-A-4-330289 JP 2000-345189 A JP 2006-137923 A

In the above prior art, in the method based on the glycerolysis reaction or transesterification reaction, the purity of diacylglycerol is low because the obtained reaction product itself has a low diacylglycerol purity, and a high-vacuum distillation facility is required to obtain a high purity. However, there are problems in terms of industrial productivity. Further, according to esterification, the purity of diacylglycerol can be increased by setting the purity of fatty acid used as a reaction raw material and setting conditions, but it is not always satisfactory in terms of balance between production efficiency and quality and cost. .
Accordingly, an object of the present invention is to provide a method for efficiently producing a diacylglycerol-rich oil and fat under industrially advantageous conditions.

  The inventor has conducted various studies on the production method of diacylglycerol, and found that high-accuracy diacylglycerol can be obtained efficiently by transesterification of monoacylglycerols.

  That is, the present invention provides a method for producing a diacylglycerol-rich oil and fat in which monoacylglycerols are transesterified under a chemical catalyst.

  According to the production method of the present invention, an oil and fat having a high diacylglycerol content can be efficiently obtained without using expensive raw materials and special equipment, which is extremely advantageous industrially.

  Monoacylglycerols used in the method of the present invention (hereinafter also referred to as “raw material monoacylglycerols”) are those in which the hydroxyl group at the 1-position of glycerin is esterified with a fatty acid (1-monoacylglycerol) and the 2-position. Examples include those in which the hydroxyl group is esterified with a fatty acid (2-monoacylglycerol) and those in which the hydroxyl group at the 3-position is esterified with a fatty acid (3-monoacylglycerol). Those having a high ratio of acylglycerol are preferred.

Although there is no restriction | limiting in particular in the carbon number of the fatty acid residue of raw material monoacylglycerol, C8-C24, Furthermore, C14-24, Especially C16-22 are preferable. Fatty acid residues include those saturated and unsaturated, specifically caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, Acyl groups derived from eicosapentaenoic acid and docosahexaenoic acid, animal oils such as beef tallow and lard, rapeseed oil, soybean oil, corn oil, sunflower oil, cottonseed oil, perilla oil, red pepper oil, flaxseed oil, safflower oil And acyl groups derived from fatty acids derived from vegetable oils such as sesame oil and palm oil.
These raw material monoacylglycerols can be used singly or in combination.

  The content of unsaturated fatty acids in all the constituent fatty acids of the raw material monoacylglycerols is 50% by mass (hereinafter, simply referred to as “%”) or more from the viewpoint of the appearance, physiological effect and industrial productivity of the final product, Further, it is preferably 60% or more, particularly 70% or more. Moreover, as an unsaturated fatty acid, oleic acid, linoleic acid, and linolenic acid are preferable.

  In addition, among the constituent fatty acids of the raw material monoacylglycerols, the content of the trans unsaturated fatty acid is preferably 8% or less, preferably 4% or less from the viewpoint of reducing the content of the trans unsaturated fatty acid in the final product. More preferably, it is 2% or less, more preferably 1.5% or less, especially 1% or less, especially 0.5% or less from the viewpoint of further reducing the content of trans-unsaturated fatty acids in the final product. Preferably there is.

  Raw material monoacylglycerols are rapeseed oil, sunflower oil, corn oil, soybean oil, rice oil, safflower oil, cottonseed oil, beef tallow, linseed oil, fish oil, etc. It can be obtained by any method such as an esterification reaction between the fatty acid derived from fats and oils and glycerin. In addition, the fats and oils can be used after separation and mixing, and those whose fatty acid composition has been adjusted by hydrogenation or transesterification, etc. This is preferable from the viewpoint of reducing the saturated fatty acid content. The reaction method may be either a chemical method using an alkali catalyst or the like, or an enzymatic method using an enzyme such as lipase. The desired raw material monoacylglycerols can be obtained by subjecting the obtained reaction product to distillation, fractionation, solvent extraction, steam distillation and the like.

  The raw material monoacylglycerols are produced from a reaction-finished oil (hereinafter, “ It is preferable to use a glycerolysis reaction finished oil). In addition, the raw fats and oils used for the glycerolysis reaction have a content of trans-unsaturated fatty acids in the constituent fatty acids of 3% or less, further 2% or less, particularly 1% or less, especially 0.5% or less in the final product. This is preferable from the viewpoint of reducing the content of trans-unsaturated fatty acids. Specifically, it is preferable to use undeodorized fats and oils such as rapeseed oil, sunflower oil, corn oil, soybean oil, rice oil, safflower oil, cottonseed oil, beef tallow, linseed oil, fish oil and the like. In addition, in this invention, undeodorized fats and oils mean the fats and oils which are not deodorized in the refinement | purification process of fats and oils.

  As a method of glycerolysis reaction of fats and oils and glycerin, a conventionally known method may be adopted, and either a chemical method or an enzymatic method is possible. From the viewpoint of reducing the triacylglycerol content in the final product, it is preferable to use a chemical method. Moreover, it is preferable to use an enzymatic method from the viewpoint of not increasing the content of trans-unsaturated fatty acids in the final product.

  When the glycerolysis reaction is carried out by a chemical method, the use of an alkali such as sodium hydroxide or calcium hydroxide or an acid such as an organic acid or a salt thereof as a catalyst improves the reaction rate and improves the hue of the reaction oil. This is preferable. The reaction temperature is preferably 100 to 300 ° C., more preferably 150 to 250 ° C. from the viewpoint of improving the reaction rate and suppressing the production of trans-unsaturated fatty acid.

  When the glycerolysis reaction is carried out by an enzymatic method, it is preferable to use a lipase as the enzyme. As the lipase, a commercially available lipase derived from microorganisms as well as those derived from animals and plants can be used. When the glycerolysis reaction is performed by an enzymatic method, for example, the reaction temperature is 0 to 100 ° C., more preferably 20 to 80 ° C., particularly 30 to 80 ° C. from the viewpoint of improving the reaction rate and suppressing the inactivation of lipase. preferable.

  The raw material monoacylglycerols in the present invention may contain monoacylglycerol, diacylglycerol, triacylglycerol and glycerin. In the embodiment of the present invention, glycerin is preferably 20% or less, more preferably 15% or less, further 0.1 to 10%, and further 0.2 to 7% from the viewpoint of increasing the purity of diacylglycerol and the purification load of the raw material. In particular, 0.5 to 7% is preferable. In addition, when using the glycerolysis reaction completion | finish oil by the glycerolysis reaction of fats and oils and glycerin, it is preferable to remove and use glycerin from the glycerolysis reaction completion | finish oil.

  The glycerin removal method is a method of removing the glycerin layer by centrifugation, a method of distilling off the glycerin by decompression, a method of removing the glycerin by steam distillation, a method of removing the glycerin layer by separation, a removal method by washing with water, adsorption Although the method of removing using an agent etc. is mentioned, it is not limited to these, You may combine these.

  From the viewpoint of improving the diacylglycerol purity of the final product, the triacylglycerol content in the raw material monoacylglycerols is preferably 50% or less, more preferably 40% or less, and particularly preferably 0.1 to 30%. Further, the diacylglycerol content in the raw material monoacylglycerols is preferably 40% or less, more preferably 30% or less, and particularly preferably 0.1 to 20%. The fatty acid content in the raw material monoacylglycerols is preferably 50% or less, more preferably 40% or less, further 0.1 to 30%, particularly 0.1 to 20%, and particularly preferably 0.1 to 10%. The monoacylglycerol content in the raw material monoacylglycerols is preferably 45% or more, more preferably 50% or more, and particularly preferably 55 to 99%.

  The transesterification of monoacylglycerols is carried out under a chemical catalyst. As the chemical catalyst, an acid catalyst or an alkali catalyst used for ordinary transesterification is used. Examples of the acid catalyst include phosphoric acid and sodium phosphate. Examples of the alkali catalyst include alkali metals or alloys thereof, alkali metal or alkaline earth metal oxides and hydroxides, alkali metal or alkaline earth metal alkoxides, and the like. Specific examples include sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium methylate, sodium ethylate, potassium methylate and the like.

  In the case of an alkali metal or alkaline earth metal alkoxide, the chemical catalyst is 0.01 to 3%, more preferably 0.05 to 2%, particularly 0.1 to 1%, based on the raw material, in terms of reactivity. It is preferable to add as follows. The reaction temperature is preferably 30 to 150 ° C., more preferably 50 to 120 ° C., from the viewpoint of improving the reaction rate. Further, in the case of an oxide or hydroxide of an alkali metal or alkaline earth metal, it is 0.001 to 2%, further 0.002 to 1%, particularly 0.005 to 0.5% with respect to the raw material. It is preferable to add to. The reaction temperature is preferably from 100 to 270 ° C, more preferably from 150 to 240 ° C, from the viewpoint of improving the reaction rate.

  In the present invention, the other conditions in the transesterification reaction of monoacylglycerols are preferably such that the pressure in the reaction system is 1.33 Pa to atmospheric pressure, particularly 1.33 to 13300 Pa, more preferably 133 to 1330 Pa. The reaction time is preferably 5 to 180 minutes, more preferably 7 to 120 minutes. In addition, the water content in the system during the reaction is preferably 2% or less, more preferably 1% or less, and particularly preferably 0.001 to 0.5%, from the viewpoint of suppressing deterioration in catalyst performance.

  In the present invention, the transesterification reaction of monoacylglycerols can be carried out batchwise, continuously, or semicontinuously. The raw material supplied to the reaction apparatus is preferable from the viewpoint of increasing the diacylglycerol content of a reaction product obtained by performing dehydration, degassing or deoxygenation in advance under reduced pressure to suppress a decrease in catalyst performance.

  After completion of the transesterification reaction, the catalyst is preferably removed by washing with water, neutralization, solvent extraction, steam distillation, adsorption or the like, or in the case of a solid catalyst by filtration or the like.

  In the present invention, the purity of the reaction product diacylglycerol is preferably 50% or more, more preferably 60 to 99%, even more preferably 70 to 98%, and particularly preferably 80 to 97%. From the viewpoint of productivity. Here, the diacylglycerol purity is [diacylglycerol / (diacylglycerol + triacylglycerol) × 100].

  In the present invention, the diacylglycerol + triacylglycerol content [% by mass] in the reaction product is preferably 50% or more, more preferably 50 to 99%, further 55 to 98%, and particularly 60 to 97%. It is preferable from the viewpoint of physiological effects and industrial productivity.

  In the present invention, if the reaction time is lengthened, the content of diacylglycerol + triacylglycerol in the reaction product increases, but the purity of diacylglycerol may decrease due to the increase in the amount of triacylglycerol produced. is there. Although this is influenced by the activity of the catalyst, it is preferable to appropriately control the reaction time and the like from the viewpoint of more efficiently producing fats and oils with high diacylglycerol purity. For example, when the content of diacylglycerol + triacylglycerol in the reaction product is less than 30 to 65%, the purity of diacylglycerol is preferably 60% or more, more preferably 60 to 99%, further preferably 70 to 98%, In particular, 80 to 97% is preferable from the viewpoint of physiological effects and industrial productivity. When the content of diacylglycerol + triacylglycerol in the reaction product is 65% or more, the purity of diacylglycerol is preferably 50% or more, more preferably 55 to 99%, further preferably 60 to 98%, particularly 70 to 97. % Is preferable from the viewpoint of physiological effects and industrial productivity.

  The reaction product obtained by transesterification under a chemical catalyst according to the method of the present invention has high diacylglycerol purity, and is therefore useful as an oil having a high physiological effect.

The diacylglycerol-rich oil and fat obtained by the transesterification reaction can be made into a product by performing post-treatment. The post-treatment is preferably performed by distillation, acid treatment, water washing, and deodorization. The distillation step refers to a step of removing fatty acid and unreacted monoacylglycerol produced as by-products from the reaction product by distilling the high-diacylglycerol-containing fat obtained by transesterification under reduced pressure. The acid treatment step refers to a step of adding and mixing a chelating agent such as citric acid to the distilled oil and further dehydrating under reduced pressure. Further, the obtained acid-treated oil may be subjected to a decoloring step by contact with an adsorbent from the viewpoint of further improving the hue and flavor. The water washing step refers to a step of performing an operation of adding water to the acid-treated oil and vigorously stirring to perform oil-water separation. Washing with water is preferably repeated a plurality of times (for example, 3 times) to obtain washing oil. The deodorizing step refers to a step of subjecting the washing oil to steam distillation under reduced pressure. Deodorization includes batch type, continuous type, semi-continuous type, etc. In addition to a method of performing a thin film deodorization device or a tray type deodorization device alone, a deodorization treatment using these thin film deodorization devices and a tray type deodorization device were used. You may carry out in combination with a deodorizing process.
By the above post-treatment, unreacted products and by-products other than diacylglycerol and triacylglycerol are removed. Therefore, it is preferable that the diacylglycerol content in the oil and fat with a high diacylglycerol content as a product falls within the range of the “purity of diacylglycerol”.

[Analysis method]
(I) Measurement of glyceride composition About 3 g of a sample of the reaction product was collected in a test tube capable of being centrifuged, and centrifuged at 3000 r / min for 10 minutes to remove the precipitated glycerin. Next, about 10 mg of the upper layer and 0.5 mL of a trimethylsilylating agent (“silylating agent TH”, manufactured by Kanto Chemical) were added to a glass sample bottle, sealed, and heated at 70 ° C. for 15 minutes. To this, 1.5 mL of water and 1.5 mL of hexane were added and shaken. After standing, the upper layer was subjected to gas chromatography (GLC) to analyze the glyceride composition.

(Ii) Content of trans-unsaturated fatty acid in constituent fatty acid Fatty acid methyl ester according to “Preparation Method of Fatty Acid Methyl Ester (2.4.1.2-1996)” in “Standard Oil Analysis Test Method” edited by Japan Oil Chemistry Association The sample obtained was measured by American Oil Chemists. Society Official Method Ce 1f-96 (GLC method).

[Preparation of raw oil and fat 1]
O-95R (Kao Co., Ltd., hereinafter the same) was used as the raw material for the transesterification reaction (raw material A). Also, rapeseed oil is added to O-95R to prepare glyceride mixed oils with different triacylglycerol contents (raw materials B, C, D), and health econa cooking oil (Kao Co., Ltd.) is added to O-95R. The mixture was added to prepare glyceride mixed oils having different diacylglycerol contents (raw materials E and F). Table 1 shows the glyceride composition of the raw oil and fat.

[Preparation of raw oil and fat 2]
804 g of non-deodorized rapeseed oil and 196 g of glycerin were placed in a 2 L 4-necked flask equipped with a stirring blade (90 mm × 24 mm), and 100 mg of calcium hydroxide was added as a catalyst while stirring under the condition of stirring at 500 r / min. Next, while flowing nitrogen gas, a glycerolysis reaction was performed under the conditions of a temperature of 210 ° C. and a reaction time of 1 hour. After cooling to 100 ° C. or lower, 118 mg of phosphoric acid was added to neutralize the catalyst. Next, the mixture was cooled to 25 ° C., centrifuged at 6000 r / min for 10 minutes, and the separated glycerin was removed to obtain a raw material G that was a raw material monoacylglycerol. The undeodorized rapeseed oil and the raw material G had trans-unsaturated fatty acid contents of 0.1% and 0.2%, respectively.

1000 g of undeodorized rapeseed oil and 343 g of glycerin were put into a 2 L 4-neck flask equipped with a stirring blade (90 mm × 24 mm), except that 0.134 g of calcium hydroxide as a catalyst and 0.158 g of phosphoric acid as a neutralizing agent were added. The glycerolysis reaction was performed under the same conditions as for the raw material G, and the raw material H was obtained. The content of trans unsaturated fatty acid in the raw material H was 0.2%.
Table 1 shows the glyceride composition of undeodorized rapeseed oil, raw material G and raw material H.

[Influence of catalyst concentration]
Test example 1
250 g of the raw material A dissolved at 70 ° C. was put in a 500 ML four-necked flask equipped with a stirring blade (75 mm × 20 mm). Next, the temperature was raised to 100 ° C. while stirring under reduced pressure of 400 Pa, and dehydration was performed under reduced pressure for 30 minutes. Subsequently, after cooling to a temperature of 80 ° C., the pressure was returned to normal pressure with nitrogen. After adding 0.4% of sodium methylate as a catalyst, the temperature was raised to 100 ° C. while stirring under a reduced pressure of 400 Pa, and a transesterification reaction was performed for 30 minutes. Thereafter, the sample was cooled to about 80 ° C., and returned to normal pressure with nitrogen to obtain sample A. Table 2 shows the glyceride composition of the reaction product. The glyceride composition is obtained after removing the separated glycerin from the reaction-finished oil according to the “analysis method” (the same applies hereinafter).

Test example 2
A sample B was obtained by carrying out a transesterification reaction in the same manner as in Test Example 1 except that the amount of sodium methylate as a catalyst was 0.2%. Table 2 shows the reaction time and the glyceride composition of the reaction product obtained.

[Influence of reaction time]
Test example 3
250 g of the raw material A dissolved at 70 ° C. was put in a 500 ML four-necked flask equipped with a stirring blade (75 mm × 20 mm). Next, the temperature was raised to 100 ° C. while stirring under reduced pressure of 400 Pa, and dehydration was performed under reduced pressure for 30 minutes. Next, the pressure was returned to normal pressure with nitrogen, 0.4% of sodium methylate was added as a catalyst while flowing nitrogen, and a transesterification reaction was started at 100 ° C. and normal pressure. Sampling was performed after 2, 5, 8, 15, 30, 60, and 120 minutes to obtain samples C, D, E, F, G, H, and I. Table 3 shows the reaction time and the glyceride composition of the obtained reaction product.

[Influence of catalyst type]
Test example 4
250 g of the raw material A dissolved at 70 ° C. was put in a 500 ML four-necked flask equipped with a stirring blade (75 mm × 20 mm). Next, the temperature was raised to 100 ° C. while stirring under reduced pressure of 400 Pa, and dehydration was performed under reduced pressure for 30 minutes. Next, after cooling to a temperature of 80 ° C., the pressure is returned to normal pressure with nitrogen, 0.01% of calcium hydroxide is added as a catalyst while circulating nitrogen, and then the ester exchange reaction is performed at a temperature of 210 ° C. and a reaction time of 1 hour After cooling to 100 ° C. or lower, the catalyst was neutralized with phosphoric acid to obtain Sample J. Table 4 shows the reaction time and the glyceride composition of the obtained reaction product.

[Influence of glyceride composition of raw oil]
Test Example 5
A sample K was obtained by carrying out the transesterification in the same manner as in Test Example 1 except that the raw material B was used as the reaction raw material for the transesterification reaction.

Test Example 6
A sample L was obtained by carrying out a transesterification reaction in the same manner as in Test Example 1 except that the raw material C was used as the reaction raw material for the transesterification reaction.

Test Example 7
A sample M was obtained in the same manner as in Test Example 1 except that the raw material D was used as the raw material for the transesterification reaction.

Test Example 8
A sample N was obtained in the same manner as in Test Example 1 except that the raw material E was used as the reaction raw material for the transesterification reaction.

Test Example 9
A sample O was obtained in the same manner as in Test Example 1 except that the raw material F was used as the reaction raw material for the transesterification reaction.

  Table 5 shows the reaction times of Test Examples 5 to 9 and the glyceride composition of the obtained reaction products.

Test Example 10
250 g of raw material G dissolved at 70 ° C. was placed in a 500 ML four-necked flask equipped with a stirring blade (75 mm × 20 mm). Next, the temperature was raised to 100 ° C. while stirring under reduced pressure of 400 Pa, and dehydration was performed under reduced pressure for 30 minutes. Next, the pressure was returned to normal pressure with nitrogen, 0.2% of sodium methylate was added as a catalyst while flowing nitrogen, and a transesterification reaction was started at 100 ° C. and normal pressure. Sampling was performed after 2, 5, 8, 15, 30, 60, and 120 minutes to obtain samples P, Q, R, S, T, U, and V. Table 6 shows the reaction time, the glyceride composition of the obtained reaction product, and the content of the trans unsaturated fatty acid.

Test Example 11
The transesterification was carried out in the same manner as in Test Example 10 except that the raw material H was used as the reaction raw material for the transesterification reaction, and the amount of sodium methylate as a catalyst was 0.15%. Sampling was performed after 1, 2, 5, 8, 11, 15, 20, and 30 minutes to obtain samples W, X, Y, Z, AA, AB, AC, and AD. Table 7 shows the reaction time, the glyceride composition of the obtained reaction product, and the content of the trans unsaturated fatty acid.

As is apparent from Tables 2 to 7, it was found that when the monoacylglycerols were subjected to a transesterification reaction under a chemical catalyst, an oil / fat composition having a high diacylglycerol content could be efficiently obtained (Test Examples 1 to 11). . From Tables 2 and 3, by increasing the catalyst concentration and increasing the reaction time, the diacylglycerol + triacylglycerol content in the reaction product increases, but the triacylglycerol concentration also increases. In order to obtain an oil / fat composition having a high diacylglycerol content, it was found that the reaction time should be determined by the amount of catalyst. That is, it was found that it is preferable to shorten the reaction time when the catalyst concentration is increased (Test Examples 1 to 3).
Table 4 shows that even when catalysts having different activities are used, a diacylglycerol + triacylglycerol content in the reaction product tends to be low, but an oil composition having a high diacylglycerol purity can be obtained. (Test Example 4).
From Tables 5 to 7, when the triacylglycerol content or diacylglycerol content in the reaction raw material increases, the diacylglycerol + triacylglycerol content in the reaction product increases, but from the point of diacylglycerol purity, It was found that the triacylglycerol content and diacylglycerol content in the reaction raw material are preferably low (Test Examples 5 to 11).
From Tables 6 and 7, when the reaction-finished oil obtained by glycerolysis reaction of undeodorized oil and glycerin is used as a raw material monoacylglycerol for transesterification, a high content of diacylglycerol with a low trans-unsaturated fatty acid content It was found that oils and fats can be obtained (Test Examples 10 and 11).

Claims (5)

Transesterification of monoacylglycerols containing 0.5-7 wt% glycerin, 0.1-30 wt% triacylglycerol, 0.1-40 wt% diacylglycerol and 45 wt% monoacylglycerol in the presence of a chemical catalyst A process for producing an oil and fat with a high content of diacylglycerol, which is reacted to obtain an oil and fat with a high content of diacylglycerol having a diacylglycerol purity [diacylglycerol / (diacylglycerol + triacylglycerol) × 100] of 50% by mass or more . The diacylglycerol content in the monoacylglycerols is 0.1 to 20% by mass, the monoacylglycerol content is 55 to 99% by mass, and the diacylglycerol purity [diacylglycerol / (diacylglycerol) 2. The method for producing fats and oils with a high content of diacylglycerol according to claim 1, wherein glycerol + triacylglycerol) × 100] is 70% by mass or more .   The method for producing fats and oils with a high diacylglycerol content according to claim 1 or 2, wherein the monoacylglycerols are glycerolysis reaction-finished oils obtained by glycerolysis reaction of fats and oils and glycerin.   The method for producing a high-diacylglycerol-containing fat according to claim 3, wherein the fat used in the glycerolysis reaction is an undeodorized fat.   The method for producing fats and oils with a high content of diacylglycerol according to any one of claims 1 to 4, wherein the content of trans-unsaturated fatty acids in the constituent fatty acids of monoacylglycerols is 2% by mass or less.