JP2020172576A - Method of producing ester-exchanged fats and oils - Google Patents

Abstract

To provide a method for producing ester-exchanged fats and oils that can be easily filtered after the neutralization of calcium hydroxide used as a glycerolysis reaction catalyst.SOLUTION: A method for producing ester exchanged oils and fats, comprising: a step of reacting glycerin with fats and oils in the presence of calcium hydroxide, followed by a step in which 1.2 mol times or more of a neutralizing agent is added to the calcium hydroxide to neutralize it.SELECTED DRAWING: None

Description

The present invention relates to a method for producing a transesterified fat and oil rich in diacylglycerol.

Diacylglycerol is used in various industrial fields such as foods and cosmetics.
Generally, diacylglycerol is produced by an esterification reaction between glycerin and a fatty acid and a glycerolisis reaction between glycerin and a fat or oil. These production methods are roughly classified into chemical methods using chemical catalysts such as hydroxides and alkoxides of alkali metals or alkaline earth metals, and enzyme methods using enzymes such as lipase (for example, Patent Document 1). 2, 2). The diacylglycerol after the reaction is decolorized by adding activated clay or the like and deodorized by contacting it with water vapor under high temperature and reduced pressure in order to obtain edible quality (for example, Patent Document 3).

Japanese Unexamined Patent Publication No. 10-234392 JP-A-2010-59406 Japanese Unexamined Patent Publication No. 2011-144343

Among the methods for producing diacylglycerol, the glycerolysis method using a sodium-based catalyst such as sodium hydroxide has an advantage of high reactivity. However, it has been found that when a sodium-based catalyst is used in the case of glycerolisis reaction between glycerin and fats and oils, glycidol fatty acid ester is produced in a high ratio as a by-product. Therefore, when various conditions for the glycerolisis reaction between glycerin and fats and oils were examined, it was found that the production of by-products was suppressed when calcium hydroxide was used as a catalyst. On the other hand, when calcium hydroxide is used as a catalyst, in the decolorization step after neutralization, the rate of separating the transesterified fat and oil rich in diacylglycerol by filtration from the decolorizing agent and the neutralization product becomes slow, and the yield becomes poor. , A new issue has arisen.
Therefore, an object of the present invention is to provide a method for producing a transesterified fat and oil that can be easily filtered after neutralization of calcium hydroxide used as a glycerolysis reaction catalyst.

When the present inventors examined the subject, it was found that the fine crystals generated when calcium hydroxide was neutralized made the filtration operation after neutralization difficult. Therefore, as a result of various studies on the neutralizing agent, it was found that the filterability can be improved by setting the molar ratio of the neutralizing agent to calcium hydroxide to a specific ratio or more.

That is, in the present invention, after the step of reacting glycerin with fats and oils in the presence of calcium hydroxide, a neutralizing agent is added 1.2 mol times or more with respect to calcium hydroxide to neutralize calcium hydroxide. It provides a method of producing transesterified fats and oils including a step.

According to the present invention, the filterability of calcium hydroxide after neutralization can be improved, and a transesterified fat and oil rich in diacylglycerol can be obtained with good productivity.

In the method for producing transesterified fats and oils of the present invention, after the step of reacting glycerin with fats and oils in the presence of calcium hydroxide, a neutralizing agent is added 1.2 mol times or more to calcium hydroxide to hydroxylate. It includes a step of neutralizing calcium.
In the present specification, "fat and oil" and "oil" are synonymous, and the substances constituting the fat and oil (oil) include not only triacylglycerol but also monoacylglycerol and diacylglycerol. That is, the fat (oil) contains any one or more of monoacylglycerol, diacylglycerol and triacylglycerol.

The glycerin used in the present invention preferably has a purity of 95% by mass or more from the viewpoint of reactivity.

The fat or oil to be reacted with glycerin may be either a vegetable fat or an animal fat or oil, but a liquid fat or oil is preferable from the viewpoint of emulsification characteristics and ease of handling of the transesterified fat or oil. The liquid fat and oil means a fat and oil that is liquid at 20 ° C. when a cooling test is carried out according to the standard fat and oil analysis test method 2.2.8.2-1996.
Specific fats and oils are mainly triacylglycerols, and are vegetable oils such as rapeseed oil, sunflower oil, corn oil, soybean oil, olive oil, rice oil, safflower oil, cottonseed oil, sesame oil, and linseed oil. Oils and fats can be mentioned. The content of triacylglycerol in the fat and oil is preferably 90 to 99.5% by mass, more preferably 93 to 99% by mass, from the viewpoint of suppressing deterioration of the fat and oil.
The fats and oils are preferably fats and oils in which unsaturated fatty acids in the fatty acids constituting the fats and oils are as large as 70 to 95% by mass from the viewpoint of emulsification characteristics of transesterified fats and oils and ease of handling. The preferred unsaturated fatty acid has 14 to 24 carbon atoms and further 16 to 22 carbon atoms, but from the viewpoint of the availability of the obtained transesterified fat and oil, linolenic acid in the fatty acid constituting the fat and oil is 4 to 70% by mass, further 6 Fats and oils as large as ~ 60% by mass are preferable.
The fats and oils can be used alone or in combination of two or more.

The reaction between glycerin and fats and oils is carried out in the presence of calcium hydroxide.
The calcium hydroxide used in the present invention may be any one used as a reaction catalyst. By using calcium hydroxide as a catalyst for the glycerolisis reaction between glycerin and fats and oils, the production of glycidol fatty acid ester, which is a by-product, is greatly suppressed.
The amount of calcium hydroxide used is preferably 0.03% by mass or more with respect to the total of the reaction raw materials, that is, glycerin and fats and oils from the viewpoint of reactivity, and 1 mass from the viewpoint that the amount of the neutralizing agent can be reduced. % Or less is preferable. More preferably, it is 0.05 to 0.5% by mass with respect to the reaction raw material. From the same point of view, the amount of calcium hydroxide used is preferably 0.0025 or more, preferably 0.11 or less, in terms of the molar ratio of the reaction raw material, that is, glycerin and the fat and oil to the glycerin group. More preferably, it is 0.004 to 0.06. The term "glycerin group" as used herein refers to the total amount of the glycerin skeleton portion in glycerin and fats and oils.

In the present invention, the ratio [FA / GLY] of the number of moles of fatty acid groups to the number of moles of glycerin groups when performing a glycerolisis reaction between glycerin and fats and oils is preferably 2.1 or more from the viewpoint of suppressing monoacylglycerol production. 2.2 or more is more preferable. Further, from the viewpoint of diacylglycerol production, 2.7 or less is preferable, and 2.6 or less is more preferable.
The ratio of the number of moles of fatty acid groups to the number of moles of glycerin groups [FA / GLY] is expressed by the following formula.
FA / GLY = (number of moles of fatty acid + number of moles of monoacylglycerol + number of moles of diacylglycerol x 2 + number of moles of triacylglycerol x 3) / (number of moles of glycerin + number of moles of monoacylglycerol + number of moles of diacylglycerol) Number of moles + number of moles of triacylglycerol)

The reaction temperature is preferably 120 ° C. or higher, more preferably 130 ° C. or higher, from the viewpoint of improving the reaction rate. Further, from the viewpoint of reducing the content of by-products, the temperature is preferably 200 ° C. or lower.

The reaction time is preferably 60 minutes or longer, more preferably 120 minutes or longer, from the viewpoint of diacylglycerol production. Further, from the viewpoint of productivity, 720 minutes or less is preferable, and 600 minutes or less is more preferable.

The reaction between glycerin and fats and oils is preferably carried out after removing water contained in the reaction raw material by depressurization, dry nitrogen bubbling or the like, from the viewpoint of reactivity and suppression of deterioration of catalytic performance.
In addition, the reaction may usually be under reduced pressure or normal pressure. The pressure when the pressure is reduced is not particularly limited, but is preferably 400 Pa or more from the viewpoint of promoting the reaction, and is preferably 26,600 Pa or less from the viewpoint of suppressing the oxidation of transesterified fats and oils. Further, when it is carried out at normal pressure, it is preferable to carry out it in a nitrogen atmosphere in order to suppress the oxidation of the obtained transesterified fat and oil.

After the completion of the glycerolysis reaction, calcium hydroxide used as a catalyst is mixed in the reaction oil. Therefore, after the completion of the glycerolysis reaction, a step of neutralizing calcium hydroxide is performed. In the present invention, the neutralization of calcium hydroxide is carried out by adding a neutralizing agent 1.2 mol times or more with respect to calcium hydroxide. By setting the molar ratio of the neutralizing agent to calcium hydroxide to 1.2 or more, the filterability of calcium hydroxide after neutralization can be improved.
The neutralizing agent is not particularly limited, but acids such as sulfuric acid, hydrochloric acid, and phosphoric acid are preferable, and phosphoric acid is more preferable, because they are insoluble in water and fats and oils and can be easily removed by filtration.

The amount of the neutralizing agent used is preferably 0.27% by mass or more, more preferably 0.28% by mass or more, based on the reaction raw material, from the viewpoint of making the neutralized product easy to filter in the decolorization step. Further, from the viewpoint of suppressing excessive addition with respect to neutralization, 1.2% by mass or less is preferable, and 0.8% by mass or less is more preferable with respect to the reaction raw material.

The molar ratio of the neutralizing agent to calcium hydroxide is 1.2 or more, preferably 1.21 or more, more preferably 1.4 or more, from the viewpoint of improving the filterability of calcium hydroxide after neutralization. More preferably, it is 1.8 or more. The upper limit of the molar ratio is not particularly limited, but 6.0 or less is preferable, and 4.0 or less is more preferable, from the viewpoint of suppressing an increase in the acid value of the neutralizing oil.

The temperature of the neutralization step, that is, the step after adding the neutralizing agent to the reaction oil in which calcium hydroxide is mixed and ending the stirring (the same applies hereinafter), is 20 ° C. or higher from the viewpoint of suppressing the reverse reaction. Is preferable, 40 ° C. or higher is more preferable, and 60 ° C. or higher is even more preferable. Further, from the viewpoint of sufficiently producing a neutralized product, 200 ° C. or lower is preferable, 160 ° C. or lower is more preferable, and 120 ° C. or lower is further preferable.

The time of the neutralization step is preferably 1 to 240 minutes, more preferably 3 to 180 minutes, and even more preferably 10 to 120 minutes from the viewpoint of sufficiently producing a neutralized product.

In the neutralization step, it is preferable to perform neutralization with stirring from the viewpoint of sufficiently producing a neutralized product. The means for stirring is not particularly limited.

After the neutralization step, it is preferable to carry out a decolorization step of bringing the adsorbent into contact with the neutralizing oil.
The adsorbent is preferably a porous adsorbent, and examples thereof include activated carbon, silicon dioxide, and a solid acid adsorbent. Examples of the solid acid adsorbent include acid clay, activated clay, activated alumina, silica gel, silica / alumina, and aluminum silicate. These can be used alone or in combination of two or more.
Of these, activated carbon and solid acid adsorbents are preferable, and acid clay and activated clay are more preferable, from the viewpoint of improving flavor and hue.
As the acid clay, for example, commercially available products such as Mizuka Ace # 20 and Mizuka Ace # 400 (all manufactured by Mizusawa Industrial Chemicals Co., Ltd.) can be used, and as the activated clay, for example, Galleon Earth V2R, Galleon Earth NV, etc. Commercially available products such as Galleon Earth GSF (all manufactured by Mizusawa Industrial Chemicals Co., Ltd.) can be used.

The amount of the adsorbent used is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, and further preferably 0.5% by mass or more with respect to the neutralizing oil from the viewpoint of improving the flavor and hue. preferable. Further, from the viewpoint of high filtration rate and good productivity, 10.0% by mass or less is preferable, 6.0% by mass or less is more preferable, and 3.0% by mass or less is further preferable with respect to the neutralized oil.

In the decolorization step, a filtration aid such as pearlite, silicon dioxide, or diatomaceous earth may be appropriately added because the filtration rate is high and the productivity is good.

The contact temperature between the neutralizing oil and the adsorbent is preferably 20 to 150 ° C, more preferably 40 to 135 ° C, and 60 to 120 from the viewpoint of reducing the content of by-products, good hue, and industrial productivity. ℃ is more preferable.

The contact time between the neutralizing oil and the adsorbent is preferably 3 minutes or more, more preferably 5 minutes or more, and further 7 minutes or more from the viewpoint of reducing the content of by-products, good hue, and industrial productivity. preferable. Further, from the viewpoint of suppressing oxidation of fats and oils and industrial productivity, 180 minutes or less is preferable, 120 minutes or less is more preferable, and 90 minutes or less is further preferable.

The pressure may be reduced pressure or normal pressure, but is preferably reduced pressure from the viewpoint of suppressing oxidation of fats and oils and decolorizing property.

In the decolorization step, it is preferable to remove the adsorbent by filtration. According to the present invention, the filtration rate can be improved, and the yield of the obtained transesterified fat and oil is excellent.
As the filtration means, any of suction filtration, pressure filtration, centrifugal filtration and the like can be carried out, and a filter used in the fat and oil decolorization step can be used.
The pressure may be reduced or pressurized. The pressure is not particularly limited, but from the viewpoint of productivity, the gauge pressure (hereinafter, the same in terms of pressure value) is preferably 0.01 MPa or more, and more preferably 0.03 MPa or more. Further, from the viewpoint of pressure resistance and safety of the equipment, 5 MPa or less is preferable, and 3 MPa or less is more preferable.

The transesterified oil and fat obtained by the method of the present invention is rich in diacylglycerol, but the content of diacylglycerol is preferably 25 to 40% by mass from the viewpoint of fluidity at low temperature and emulsification characteristics. The transesterified fat and oil contains triacylglycerol in addition to diacylglycerol, and also contains unreacted glycerin and monoacylglycerol, although the amount is smaller than these.
From the viewpoint of fluidity at low temperature and emulsification characteristics, the amount of monoacylglycerol in the transesterified fat and oil is preferably small, and the content thereof is preferably 10% by mass or less, more preferably 7% by mass or less.

The transesterified fats and oils obtained by the method of the present invention can be used in the same manner as general edible fats and oils by performing a refining step as necessary in addition to the above steps.

In the following examples, "%" means "mass%".

[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 centrifugation and centrifuged at 3000 r / min for 10 minutes to remove the precipitated catalyst. Next, about 10 mg of the upper layer and 0.5 mL of a trimethylsilylating agent (“silylating agent TH”, manufactured by Kanto Chemical Co., Inc.) were added to a glass sample bottle, the bottle was sealed, and the mixture was 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) [Yield calculation method]
The yield was calculated from the formula (1) using the mass [a] charged into the filtration device and the mass [b] of the filtered decolorized oil.
Yield = b / a × 100 (%) (1)

[Example 1]
974.7 g of deodorized rapeseed oil and 25.3 g of glycerin, which are the raw materials for the glycerolisis reaction, were placed in a 2L 4-neck flask equipped with a stirring blade (90 mm × 24 mm). The ratio of the number of moles of fatty acid residues to the number of moles of glycerin group [FA / GLY] was 2.4.
Next, while stirring at 400 r / min, dehydration was carried out under reduced pressure at 80 ° C. and 400 Pa for 30 minutes. Next, the pressure was returned to normal pressure, and 1.5 g of calcium hydroxide (record concentration 97.9%, manufactured by Kanto Chemical Co., Inc.) was added as a catalyst. Next, a glycerolysis reaction was carried out under a reduced pressure of 8000 Pa at a temperature of 140 ° C.
After the diacylglycerol content reached equilibrium 300 minutes after the start of the reaction, the mixture was cooled to 90 ° C. and phosphoric acid (results concentration 85.5%, manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.) was used as a neutralizing agent. 83 g was added and mixed for 60 minutes to obtain a reaction product. The molar ratio of phosphoric acid to calcium hydroxide was 1.25. The analysis results of the reaction products are shown in Table 1.

Next, the neutralizing oil was dehydrated under reduced pressure for 30 minutes at 80 ° C. and 400 Pa while stirring at 400 r / min. Then, the pressure was returned to normal pressure, and 10.0 g of activated clay (Galleon Earth V2R, manufactured by Mizusawa Industrial Chemicals Co., Ltd.) and 2.1 g of filtration aid (RocaHelp 4109, manufactured by Mitsui Mining & Smelting Co., Ltd.) were added. Next, the decolorization treatment was performed under the condition of a temperature of 100 ° C. under a reduced pressure of 8000 Pa.
After 60 minutes from the start of decolorization, the mixture was cooled to 80 ° C., transferred to a filtration device whose jacket was kept warm at 80 ° C., subjected to constant pressure filtration, and the filtrate (bleached oil) was recovered. Filtration was performed under the conditions of a filtration area of 39 cm ² , filter paper (No. 24 manufactured by Azumi Filter Paper Co., Ltd.), and a pressurizing pressure of 0.08 MPa.
Table 1 shows each condition, the filtration time for obtaining 250 mL of the filtrate, and the yield of the decolorized oil.

[Example 2]
Except for the addition of 3.17 g of phosphoric acid (results concentration 85.5%), the glycerolysis reaction, decolorization treatment, and constant pressure filtration were carried out in the same manner as in Example 1, and the filtrate (decolorized oil) was recovered. The molar ratio of phosphoric acid to calcium hydroxide was 1.40.
Table 1 shows each condition, the filtration time for obtaining 250 mL of the filtrate, and the yield of the decolorized oil.

[Example 3]
Except for the addition of 4.23 g of phosphoric acid (results concentration 85.5%), glycerolysis reaction, decolorization treatment, and constant pressure filtration were carried out in the same manner as in Example 1, and the filtrate (decolorized oil) was recovered. The molar ratio of phosphoric acid to calcium hydroxide was 1.86.
Table 1 shows each condition, the filtration time for obtaining 250 mL of the filtrate, and the yield of the decolorized oil.

[Example 4]
The filtrate (bleached oil) was recovered by performing a glycerolysis reaction, a decolorization treatment, and a constant pressure filtration in the same manner as in Example 1 except that 5.29 g of phosphoric acid (results concentration 85.5%) was added. The molar ratio of phosphoric acid to calcium hydroxide was 2.33.
Table 1 shows each condition, the filtration time for obtaining 250 mL of the filtrate, and the yield of the decolorized oil.

[Comparative Example 1]
Except for the addition of 1.76 g of phosphoric acid (results concentration 85.5%), glycerolisis reaction, decolorization treatment, and constant pressure filtration were carried out in the same manner as in Example 1, and the filtrate (decolorized oil) was recovered. Filtration was slow and stopped after 120 minutes. The molar ratio of phosphoric acid to calcium hydroxide was 0.78.
Table 1 shows each condition, the filtration time for obtaining 250 mL of the filtrate, and the yield of the decolorized oil.

[Comparative Example 2]
Except for the addition of 2.38 g of phosphoric acid (results concentration 85.5%), glycerolysis reaction, decolorization treatment, and constant pressure filtration were carried out in the same manner as in Example 1, and the filtrate (decolorized oil) was recovered. The molar ratio of phosphoric acid to calcium hydroxide was 1.05. Filtration was slow and stopped after 180 minutes.
Table 1 shows each condition, the filtration time for obtaining 250 mL of the filtrate, and the yield of the decolorized oil.

[Comparative Example 3]
Except for the addition of 2.65 g of phosphoric acid (results concentration 85.5%), glycerolysis reaction, decolorization treatment, and constant pressure filtration were carried out in the same manner as in Example 1, and the filtrate (decolorized oil) was recovered. The molar ratio of phosphoric acid to calcium hydroxide was 1.16. Filtration was slow and stopped after 180 minutes.
Table 1 shows each condition, the filtration time for obtaining 250 mL of the filtrate, and the yield of the decolorized oil.

[Example 5]
The glycerolisis reaction and decolorization treatment were carried out in the same manner as in Example 1 except that 3.73 g of hydrochloric acid (record concentration 36.0%) was added as a neutralizing agent, and constant pressure filtration was carried out. The molar ratio of hydrochloric acid to calcium hydroxide was 1.86. Table 1 shows the filtration time for obtaining 250 mL of each condition and the resulting filtrate, and the yield of decolorized oil.

As is clear from Table 1, the glycerolysis reaction was carried out using calcium hydroxide as a catalyst as in Examples 1 to 5, and then a neutralizing agent was added 1.2 mol times or more to the calcium hydroxide to neutralize. By doing so, the activated clay and the catalyst neutralized product could be easily filtered and removed in the decolorization step, and the ester-exchanged fat and oil could be obtained in a high yield. On the other hand, when the neutralizing agent was less than 1.2 mol times the amount of calcium hydroxide as in Comparative Examples 1 to 3, the activated clay and the catalyst neutralized product could not be easily filtered in the decolorization step. The yield was low.

Claims (6)

Transesterification including a step of reacting glycerin with fats and oils in the presence of calcium hydroxide, followed by a step of adding 1.2 mol times or more of a neutralizing agent to calcium hydroxide to neutralize calcium hydroxide. Method for producing fats and oils. The method for producing a transesterified fat or oil according to claim 1, wherein the ratio of the number of moles of fatty acid groups in the fat or oil to the number of moles of glycerin groups in the step of reacting glycerin with the fat or oil is 2.1 or more and 2.7 or less. The method for producing a transesterified fat or oil according to claim 1 or 2, wherein the amount of calcium hydroxide used is 0.03% by mass or more based on the total amount of glycerin and the fat and oil. The method for producing a transesterified fat or oil according to any one of claims 1 to 3, wherein the neutralizing agent is one or more acids selected from sulfuric acid, hydrochloric acid and phosphoric acid. The method for producing a transesterified oil or fat according to any one of claims 1 to 4, further comprising a decolorizing step of bringing the adsorbent into contact with the neutralizing oil after the neutralization step. The method for producing a transesterified fat or oil according to claim 5, wherein the adsorbent is one or more selected from activated carbon and a solid acid adsorbent.