JPS5928482A - Method for ester interchange reaction of fat or oil - Google Patents

Abstract

PURPOSE:To obtain a final reaction product with very little by-products, by bringing a water absorbent into contact with an ester interchange reaction mixture in a given stage of the ester interchange reaction of a fat or oil with an enzyme. CONSTITUTION:An ester interchange reaction is carried out by using a fat or oil, e.g. fat or oil, an alcoholic ester or fatty acid, as a substrate with an enzyme having the ester interchange reaction ability. In the process, 0.3-20wt%, preferably 1-15wt%, based on the substrate, water is added to the reaction system to carry out the ester interchange reaction. When the rate of the ester interchange reaction reaches 10% or more, preferably 30-45%, salt or metallic oxide free from water of crystallization, e.g. silica gel, zeolite, activated alumina, Glauber's salt, calcined gypsum or calcium carbonate, is brought into contact with the reaction system. The reaction is further continued to give 80% or more, preferably 90% or more, rate of the ester interchange reaction.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for enzymatic transesterification of oils and fats. More specifically, when an enzyme having transesterification activity is used to carry out a transesterification reaction in the presence of water in excess of the water content necessary and sufficient to activate the enzyme, and when the transesterification reaction rate reaches a factor of 10 or higher, When a water absorbing agent is brought into contact with the reaction system and the reaction continues, the table changes to /+? This invention relates to a method for transesterification of oils and fats.

Conventionally, the transesterification reaction of oils and fats has been carried out by adding a small amount of water that activates the enzyme to the enzyme.
Even this small amount of water accelerates the hydrolysis reaction and tends to produce undesirable products. For example, when transesterifying oils and fats whose main component is triglyceride, in addition to triglyceride (TG), diglyceride (DG), monoglyceride (11/] a ), and free fatty acid (1"
F A ), by-products of glycerin (G) are produced in many needles, which not only reduces the reaction yield of TG (but also makes post-treatment very difficult to obtain only TG).

Among these by-products, there is a large amount of "J-" produced by KDG,
During post-treatment (including purification) of the produced DGfd, since it has properties similar to TGK, an industrial large-scale separation method for TG and DG has not yet been established, even on a laboratory scale.

And, the presence of DG and the above-mentioned byproducts other than DG,
It is easy to form a eutectic mixture with TG, and the generation of crystal nuclei is incomplete, making it difficult to separate the desired TG acid components and causing a large fractionation loss. Furthermore, if a large amount of these by-products is mixed into a final product containing TG as a main component, it will have an adverse effect such as a decrease in solid fat content.

Furthermore, according to the experimental results of the present inventors, when the DG content of the reactant is high, randomization of glycerides during the purification process in post-treatment, especially during distillation deacidification, molecular distillation, deodorization, etc., which are processed at high temperatures. It was found that the chemical reaction was accelerated and the glyceride composition obtained by the reaction changed significantly, which not only changed the physical properties but also tended to increase the coloration of the final product. This can be inferred from the fact that oil and fat engineers often experience that exposing high acid value natural oils and fats that contain large amounts of DG to high temperatures without proper treatment can have adverse effects such as changes in physical properties and coloration. I can do it. Appropriate post-treatments here include degumming treatment, alkali deoxidation treatment, adsorption treatment, etc., but from an industrial perspective, there are limits to the amount of DG@ that can be removed by these methods. For example, the DG content of the raw material oil would be around 1JlO%.

The above is exactly the same in transesterification of oils and fats using enzymes, and it is extremely important to suppress by-products in the final reaction product as much as possible.

However, in general, reactions using enzymes have a high reaction activity in a system with a high water content, but in the transesterification of oils and fats, the hydrolysis reaction, which is a side reaction, also increases and a large amount of byproducts are included. Become. Therefore, in order to eliminate these drawbacks, preparation of an enzyme agent having reaction activity in a system with little water (Japanese Patent Publication No. 57-27159),
Currently, this problem is dealt with by a method of balancing the transesterification reaction rate and the hydrolysis reaction rate (Japanese Unexamined Patent Publication No. 52-fD4506).

Normally, when the water content in the reaction system is small, less than 0.2% by weight based on the substrate, or when a substance that absorbs water even more than that is added, the transesterification reaction rate will be slow even if a large amount of enzyme is used. The disadvantage is that it is slow and takes too much time for industrial use.Also, when the water content in the reaction system is 0.2% by weight or more, the higher the water content, the faster the transesterification reaction rate. The hydrolysis reaction also becomes large, resulting in a large amount of by-products, and balancing them requires very advanced and detailed techniques.

Therefore, in the transesterification reaction of oils and fats, the present inventors have developed special enzyme preparations that allow the reaction to proceed while reducing water content, and the need for an exquisite balance between the transesterification reaction rate and the hydrolysis reaction rate. As a result of extensive research into a transesterification method for fats and oils that yields a final reaction product with very few by-products and has a sufficiently fast reaction rate, we have developed a method for transesterifying fats and oils using enzymes with high activity. We have completed a transesterification method for oils and fats according to the present invention, which allows for the transesterification of oils and fats, and in which side reactions are extremely suppressed.

The method for transesterification of fats and oils of the present invention involves transesterifying fats and oils using an enzyme having transesterification activity, and in the presence of an amount of water greater than the amount necessary to activate the enzyme, the reaction rate is reduced. The method is characterized in that when the reaction temperature reaches 10 or more, the reaction system is brought into contact with the salt or metal oxide that has lost crystal water, and the reaction is further continued.

According to the transesterification method of the present invention, when the reaction is carried out using an enzyme having transesterification activity using fats and oils such as fats and oils, alcohol esters, and fatty acids as substrates, moisture is reduced to 0.0% relative to the substrate. 3 to 20 parts by weight and 4 parts, preferably 1 to 15 parts by weight, are added to react, and when the Nissdell exchange reaction rate reaches 10 parts or more, preferably about 30 to 45%, water of crystallization is lost in the reaction system. Salts or metal oxides (water absorbing agent) are brought into contact with each other, and the reaction is continued until the transesterification reaction rate is 80% or more, preferably IrJ-qo9!1 or more, and the by-products are completely removed. Less final reaction product can be obtained.

The above-mentioned substrate refers to fats and oils or fats and oils and fatty acids, and when glycerin, monoglyceride, diglyceride, alcohol ester of fatty acid, etc. are present in the system, these substances are also included in the above-mentioned substrate.

The above-mentioned fats and oils used in the present invention include general vegetable and animal fats, processed fats and oils, and mixtures thereof, such as soybean oil, cottonseed oil, rapeseed oil, olive oil, corn oil, coconut oil, These include safflower oil, beef tallow, lard, and fish oil. In addition, glycerides with specific compositions are used as raw materials for cocoa butter substitutes, namely 1,3-distearol-2-oleoglyceride, 1-palmito-2-oleo-6-stialoglyceride, and 1,3-dipalmito-2.
- When oleoglyceride is the target of the transesterification reaction, oils and fats containing a large amount of oleic acid at the 2-position of the glyceride, such as olive oil, camellia oil, sasanqua oil, palm oil, monkey fat, illipe butter, kokum butter, Shea butter, Maua butter, Furwara butter, Porneotallow butter, or fractionated fats and oils thereof can be used.

Further, as the fatty acid, a linear saturated or unsaturated fatty acid having 2 to 22 carbon atoms can be used. For example, palmitic acid, stearic acid, oleic acid, etc. can be used.

Examples of alcohol esters of fatty acids include esters of the above fatty acids and 1α-chain saturated alcohols having 1 to 6 carbon atoms, such as methyl palmitate, ethyl palmitate, methyl stearate, and ethyl stearate. I can do it.

The enzyme having all transesterification activities used in the present invention includes lipase. As the cough lipase, Rhizopus type, Aspergillus type, Candida type, Mucor type, Pancreatic haze, etc. can be used, and many of these lipases are available as commercial products. Also, glyceride 1.
When specifically transesterifying the fatty acid group at the 3-position, a lipase having characteristics suitable for the purpose, such as Rhizopus deremer, Rhizopus abbonicus, Mucorjabonicus, etc. may be used.

Preferred lipase enzymes fat (activity unit U) contain the group 5
t, (unit amount), 5 to 10000 U/r.

More preferably it is 50-10ou/r. however,
The activity unit U of the enzyme is 5ml of olive oil emulsion and 0.1
M phosphate buffer 4 ml'i? 1 enzyme was added and reacted for 30 minutes at 37°C, for every fatty acid produced corresponding to 0.06 ml of 0.05N aqueous sodium hydroxide solution.
It was defined as activity unit (U).

The transesterification reaction of the present invention is preferably carried out at a reaction temperature of 20 to 60°C, preferably 30 to 50°C.

For example, if a mixture of high melting point oil and fatty acid is used as a reaction substrate, the reaction temperature may result in a non-uniform system, but in such cases, an organic solvent inert to lipase reaction substrate. Existence of this type (as residual solvent, n
-hexano, industrial hexano, petroleum ether, etc., and can be used in an amount of 0.1 to 5 times the amount (weight) of the substrate.

Even if the enzyme has reaction specificity, it is possible to increase the reaction yield by using these methods. Further, although the enzyme can be used alone, it is usually preferable to use it by adsorbing or immobilizing it on diatomaceous earth, alumina, activated carbon, or other known supports.

During the reaction, the transesterification reaction rate is measured over time, and when the reaction rate reaches 10 or more, preferably about 30 to 45, silica gel, zeolite, activated alumina, sulfur salt, baked stone kola, calcium carbonate, etc. The salt vessel or metal oxide that has lost its water of crystallization is brought into contact and the reaction is continued. The phrases used for the above-mentioned salts or metal oxides are not necessarily specified depending on their type, etc., but they are usually used in the same amount or less as the substrate listed in iQ.
Within the range of 1% by weight based on the substrate, 1. The transesterification reaction rate is determined by taking, for example, C54 from the glyceride composition by carbon number, determining the proportion of 054 in the raw material and the theoretical equilibrium value, and calculating the C54 after a period of time. It is calculated from the following formula from the ratio of .

Contact with these salts or metal oxides further accelerates the transesterification reaction, improving the reaction rate compared to the case without contact, reducing undesirable by-products, and improving the recovery rate of the reaction target component. Good reactants are obtained. The reaction time at this time was 10 to 80 hours, and usually 1'120 to 70 hours. After the reaction, non-oil-soluble substances such as enzymes, supports, salts, etc. are removed by filtration, adsorption, etc., and post-treatment (purification, fractionation) is performed as necessary to efficiently obtain the target product. , a high recovery rate can be obtained.

Hereinafter, the effects of the present invention will be explained using Examples.

Example 1 Hydrogenated palm oil 501 and soybean oil 702 were mixed with Celite 2.5
About 2.5% by weight of commercially available Candida cylindracelipase and 15% of water were stirred in a closed container at 40°C, and when the reaction rate reached 40%, the water absorbing agent (Bou's Salt) was mixed with 5% of water.
01 was added and the reaction continued for up to 30 hours. The resulting reaction mixture was filtered, and the oil remaining on the if3 paper was washed with hexane. The solvent was removed by evaporation to obtain a reaction oil. The composition of the obtained reaction oil was 1'i: 92% TG, 6.5% DG, 2% MG skin, and 1.4% FF'A. Moreover, the final reaction rate was 95%. The reaction rate was determined by comparing the composition of the same mixture when intermolecular transesterification was completed in the presence of an alcohol metal catalyst and the number of carbon atoms measured by gas chromatography.

Comparative Example 1 The same operation as in Example 1 was carried out except that a water-absorbing agent (sulfuric acid) was (c) added during the reaction, and the reaction was carried out for 30 hours.

The composition of the obtained reaction oil was TG4B, 6chi, DG28.4
H, MG 3.2%, FFA 19.8%, and the final reaction rate was 75 H.

Example 2 100 parts (parts by weight, same hereinafter) of palm intermediate fraction and 75 parts of stearic acid were mixed with 0.0 parts of an enzyme specific for the 1,5 position.
3 parts and 6 parts of Celite were added by infiltrating with 1.0 part of water,
200 parts of industrial hexane was added as a solvent and reacted at 40°C. After 4 hours of reaction, the change in carbon number was examined by gas chromatography and the reaction rate was 35%, so 10 parts of silica gel was added to the reaction system and the reaction was continued for an additional 10 hours. The composition of the obtained reaction product was as shown in Table 1.

Comparative Example 2 The same operation as in Example 2 was carried out except that silica gel was not added during the reaction, and the reaction was carried out for 14 hours. The composition of the reaction product obtained was as shown in Table 1.

Example 8 To 100 parts of palm soft oil and 90 parts of stearic acid, 1.3
0.3 parts of a position-specific enzyme and 0.6 parts of Celite were infiltrated with 2.0 parts of water, and 1 part of industrial hexane was used as a solvent.
50 parts were added and reacted at 40°C. After reacting for 5 hours, the reaction rate was 40%, so 10 parts of baked radish was added to the reaction system, and the reaction was continued for an additional 15 hours. The composition of the obtained reaction product was as shown in Table 2.

Comparative Example 8 The reaction was carried out in the same manner as in Example 5, except that sacrifice was not added during the reaction, and the reaction was carried out for 20 hours. The composition of the obtained reaction product is shown in Table 2.

Comparative Example 4 The same operation as in Example 3 was carried out, except that the amount of water used was 0.1 part, and the addition of Yakisekko during the reaction was carried out, and the reaction was carried out for 20 minutes.
I did it for an hour. The composition of the obtained reaction product is shown in Table 2.

Claims (1)

[Claims] (When transesterifying 11 oils and fats using an enzyme having transesterification activity, the reaction rate reaches 10% or more in the presence of more water than is necessary to activate the enzyme. A method for the transesterification reaction of oils and fats, which is characterized in that the reaction system is brought into contact with a chloride or metal oxide that has lost its water of crystallization, and the reaction is further continued. (2) Loss of water of crystallization f: The salts or metal oxides are one or two selected from the group consisting of silica gel, zeolite, activated alumina, sulfur salt, baked stone kola, and calcium carbonate.
The method for transesterification of oils and fats according to claim (1), which comprises more than one type of substance.