JP2000297295A - Hydrolysis of oil and fat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for hydrolyzing an oil and fat, hardly causing reduction of the enzyme activities accompanied with the increase of the number of treatment, and stable and good in efficiency over a long time. SOLUTION: This method for hydrolyzing an oil and fat comprises sending liquid of an oil-phase substrate from a substrate-circulating vessel 2 to an enzyme column 3 packed with an enzyme-immobilizing carrier, bringing the reaction liquid passed through the enzyme column 3 into contact with a water- phase substrate in an oil and water-mixing vessel 4, and subjecting the resultant mixture to oil separation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an efficient method for hydrolyzing fats and oils without a decrease in enzyme activity accompanying an increase in the number of treatments.

[0002]

2. Description of the Related Art The hydrolysis of fats and oils is important in providing fatty acids and glycerin, which are important basic materials of the oil chemical industry. For such continuous hydrolysis of fats and oils, a method of passing fats and oils through a flow-type reactor in which a fat and oil-degrading enzyme (lipase) is fixed to a resin or a membrane is generally used. For example, the following techniques are known. (1) 60% by weight with respect to fats and oils
A method in which a mixed solution obtained by mixing water in a degree is passed through an enzyme-filled reactor. (2) A method in which only an oil or fat containing no aqueous phase substrate is passed through a lipase immobilized on a polysaccharide gel containing a large amount of water (Japanese Patent Application Laid-Open No. 58-146284).
(3) A method of circulating an oil / fat storage tank and a humidifier to uniformly mix oil / fat and water, and to pass a mixed liquid having a uniform water content through an enzyme-filled reactor (Japanese Patent Laid-Open No. Hei 4- 3
No. 35881). (4) The fats and oils and water are put into the substrate circulation tank, and only the oil phase substrate is supplied into the enzyme tower in a state where the oil phase and the water phase are separated, and the discharged reaction solution is placed at the bottom of the aqueous phase in the substrate circulation tank. How to return (Kosugi, Y., Tomizuka, N, J. Am.
Oil. Chem. Soc. 72; 1329 (1995)).

[0003]

In the method (1), the hydrolysis rate is increased due to the high water content of the mixture, but the enzyme is desorbed with time, so that the enzymatic activity is increased when the number of treatments is increased. Is reduced. In the method (2), the enzyme is not desorbed with time as in the method (1). However, water required for hydrolysis tends to be insufficient according to use, and glycerin is accumulated in the immobilized enzyme. As a result, the equilibrium may be tilted toward the fat or oil, resulting in insufficient decomposition of the fat or oil. In the method (3), it is difficult to separate the oil phase and the aqueous phase after the decomposition, and a process for separation and additional facilities are required.
Further, any of the methods (1) to (3) has a problem that the apparatus is complicated and the operation of the enzyme-filled reactor is very difficult. In the method (4), the water concentration of the oil phase passing through the enzyme reactor is low, and the oil phase and the water phase after the decomposition are easily separated. However, the extraction of glycerin in the reaction solution is insufficient, and the method is high. There is a problem that it is difficult to obtain a decomposition rate.

[0004] An object of the present invention is to provide a method for efficiently hydrolyzing fats and oils by a simple operation without a decrease in enzyme activity over time, with a high hydrolysis rate.

[0005]

Means for Solving the Problems The present inventors send an oil-phase substrate from an inside of a substrate circulation tank to an enzyme tower, and contact the reaction solution passing through the enzyme tower with the aqueous phase substrate in an oil-water mixing tank. After that, if oil-water separation is performed in the substrate circulation tank, hydrolysis in the enzyme tower is promoted by a very small amount of water in the oil phase substrate sent to the enzyme tower. Without detachment,
The enzyme activity is stable over a long period of time, and then the glycerin produced by hydrolysis dissolves in the aqueous phase substrate by contacting the reaction solution with the aqueous phase substrate. Is done well,
Further, they have found that the equipment used is simple and easy to operate.

That is, according to the present invention, an oil phase substrate is sent from a substrate circulation tank to an enzyme tower filled with an enzyme-immobilized carrier,
Provided is a method for hydrolyzing fats and oils in which a reaction solution passed through the enzyme tower is brought into contact with an aqueous phase substrate in an oil / water mixing tank, followed by oil / water separation.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION In the method of the present invention, first, an oil phase substrate is sent from a substrate circulation tank containing an oil phase substrate and an aqueous phase substrate to an enzyme tower filled with an enzyme-immobilized carrier. Oil phase substrates include triglycerides, diglycerides, monoglycerides,
It is a mixture of free fatty acids and the like, preferably oils and fats. Further, since hydrolysis requires the presence of water, it is particularly preferable to contain a trace amount of water. However, containing a large amount of water is not preferable because the immobilized enzyme is desorbed with time and the enzyme activity is reduced. The amount of water in the oil phase substrate is from the saturation solubility (the maximum amount of water dissolved in the oil phase substrate) to 5
% By weight (hereinafter simply referred to as "%"), more preferably 4 to 4%, particularly preferably 3 to 3%. For example, the contact between the oil phase substrate and the aqueous phase substrate when the two substrates are accommodated in the substrate circulation tank, or the contact between the aqueous phase substrate and the reaction solution, which will be described later, reduce the amount of water in the oil phase substrate to the saturation solubility. It can be 5%. The aqueous phase substrate is a mixture of water and a water-soluble substance such as glycerin, preferably water.
The water may be any of tap water, well water, distilled water and ion-exchanged water, and ion-exchanged water is particularly preferred.

In order to feed the oil phase substrate, it is preferable to separate both phases without applying a shearing force such as stirring in the substrate circulation tank. Further, it is preferable that the end of the oil phase substrate extraction line for sending the oil phase substrate from the substrate circulation tank to the enzyme tower be located near the upper surface of the oil phase substrate in the substrate circulation tank. The amount of the oil phase substrate to be sent can be appropriately determined in consideration of the enzyme treatment capacity and the like. The enzyme is not particularly limited as long as it can hydrolyze fats and oils, and examples thereof include lipase and esterase. Also, a random type, an α-position selection type, or the like can be arbitrarily selected. The carrier for immobilizing the enzyme and the immobilization method are not particularly limited, and examples thereof include a carrier and a method described in JP-A-1-153090. The supply of the oil phase substrate to the enzyme tower may be either an upward flow from the bottom to the top or a downward flow from the top to the bottom.

[0009] The oil phase substrate sent to the enzyme tower is decomposed by the immobilized enzyme in the enzyme tower to produce diglyceride, monoglyceride and glycerin. If the water content in the oil phase substrate is very small, the immobilized enzyme does not desorb from the carrier,
In addition, glycerin in the reaction solution after passing through the enzyme tower moves to the aqueous phase substrate in the oil / water mixing tank, so that the reaction does not lean to the fat or oil side, and the decomposition rate of fat or oil can be increased.

Next, the reaction solution discharged from the enzyme tower is brought into contact with an aqueous phase substrate in an oil / water mixing tank provided separately from the substrate circulation tank. By such contact, diglyceride and monoglyceride remain in the oil phase matrix, and glycerin transfers to the aqueous phase matrix. At this time, a small amount of water is included in the oil phase matrix due to the shearing force at the time of contact.

When the reaction solution is brought into contact with the aqueous phase substrate in the oil / water mixing tank, the oil / water mixing tank is stirred or the aqueous phase substrate is poured from the top of the tank in order to bring the reaction liquid and the aqueous phase substrate into sufficient contact. It is preferable that the reaction liquid is brought into a downward flow to the bottom and the reaction liquid is brought into countercurrent contact as an upward flow from the bottom of the tank to the top of the tank, or both are used in combination. Next, the reaction solution / aqueous substrate mixture in the oil / water mixing tank is sent to the substrate circulation tank. If the shearing force applied to the oil / water interface in the substrate circulation tank is too large, the amount of water in the oil phase substrate will be too high. It is preferable to be arranged near the oil-water interface in the inside. In addition, it is preferable to supply the aqueous phase substrate in the substrate circulation tank to the oil-water mixing tank from the viewpoint of the capacity and economy of the substrate circulation tank. Further, a method in which the aqueous phase substrate in the substrate circulation tank is continuously supplied to the oil / water mixing tank, and the reaction solution overflowing from the oil / water mixing tank and the aqueous phase substrate are returned to the substrate circulation tank is particularly preferable.

Next, the oil phase substrate and the aqueous phase substrate are separated by standing or centrifuged in a substrate circulation tank. In the case of centrifugation, it is preferable to install a centrifugal separator in the line before the substrate circulation tank, and to send the separated oil phase substrate and aqueous phase substrate to the substrate circulation tank through separate lines.

According to this process, the oil phase substrate in the substrate circulation tank contains a small amount of water due to contact with the aqueous phase substrate, in addition to oil and fat decomposition products such as oils and diglycerides. Further, if the above steps are continuously repeated, the hydrolysis of fats and oils further proceeds due to the presence of a trace amount of water in the oil phase substrate, and the fats and oils can be decomposed to a desired decomposition rate.

FIG. 1 shows an example of an apparatus for carrying out the oil / fat hydrolysis method of the present invention. In FIG. 1, an apparatus 1 for hydrolyzing fats and oils includes a substrate circulation tank 2, an enzyme tower 3, an oil / water mixing tank 4 for bringing a reaction solution having passed through the enzyme tower 3 into contact with an aqueous phase substrate, and an oil phase in the substrate circulation tank 2. An oil phase substrate extraction line 5 for sending the substrate to the enzyme tower 3, and an oil / water mixing tank 4
, A reaction liquid discharge line 6 for feeding the aqueous solution, an aqueous phase substrate supply line 7 for feeding the aqueous phase substrate in the substrate circulation tank 2 to the oil / water mixing tank 4, and a reaction solution contacted with the oil / water mixing tank 4. The apparatus is provided with a reaction liquid / aqueous phase substrate mixture return line 8 for sending the aqueous phase substrate mixture to the substrate circulation tank 2.

The substrate circulation tank 2 and the enzyme tower 3 have jackets for heating and keeping warm. The shape of the substrate circulation tank 2 (tank height / tank diameter, etc.) is not particularly limited as long as oil / water separation in the substrate circulation tank 2 can be performed well. The shape of the enzyme tower 3 is not particularly limited as long as it can withstand the pressure of a pump used when the oil phase substrate is sent from the substrate circulation tank 2 to the enzyme tower 3. A stirrer 11 is provided in the oil / water mixing tank 4 in order to sufficiently bring the reaction solution into contact with the aqueous phase substrate sent from the substrate circulation tank 2. The oil phase substrate in the substrate circulation tank 2 is supplied to the enzyme tower 3 in the oil phase substrate extraction line 5.
A pump 9 for feeding the liquid to the container is provided. The aqueous phase substrate supply line 7 is provided with a pump 10 for sending the aqueous phase substrate extracted from the substrate circulation tank 2 to the oil / water mixing tank 4. The reaction liquid / aqueous phase substrate mixed solution return line 8 has an end on the substrate circulation tank 2 side near the oil-water interface in the substrate circulation tank 2 in order to easily perform oil / water separation in the substrate circulation tank 2. The aqueous phase substrate supply line 7 and the reaction solution discharge line 6
It is installed in the oil-water mixing tank 4.

[0016]

EXAMPLE 1 In FIG. 1, lipase (Lipase AY, Lipase AY) was added to an ion exchange resin (Duolite A-568, manufactured by Diamond Shamrock).
20 g of immobilized lipase immobilized with Amano Pharmaceutical Co., Ltd.)
To a jacketed stainless steel column (enzyme tower 3:
(Inner diameter: 43 mm, filling height: 47 mm), and the temperature was kept at 40 ° C. by a jacket. Substrate circulation tank 2 (132 m inner diameter)
m, height 380 mm) and 1200 g of ion-exchanged water, and further, soybean white squeezed oil (triglyceride 100
%) And 2000 g were gently added, and the mixture was kept at 40 ° C. with a jacket. Using the pump 10, the aqueous phase substrate was continuously supplied from the lower end of the substrate circulation tank 2 to the oil-water mixing tank 4 (capacity 200 mL, stirred at 400 rpm) at 0.24 L / min, and the overflowed aqueous phase substrate was It was returned to the oil / water separation interface of the substrate circulation tank 2 through the reaction liquid / water phase substrate return line 8. After the temperature of the enzyme tower 3, the oil phase substrate, and the aqueous phase substrate reached 40 ° C., the pump 9 was used to supply the oil phase substrate from the upper end of the oil phase substrate at 0.24 L / min to the enzyme tower 3 to decompose. Started. The reaction solution discharged from the enzyme tower 3 entered the oil / water mixing tank 4 through the reaction solution discharge line 6, was mixed with the aqueous phase substrate, and the generated glycerin was transferred to the aqueous phase substrate. In addition, part of the water was transferred to the oil phase substrate by stirring. The overflowed reaction liquid / aqueous phase substrate mixture was returned to the oil / water separation interface of the substrate circulation tank 2 through the reaction liquid / aqueous phase substrate return line 8, and was allowed to stand still for oil / water separation. This process was repeated continuously, and the reaction was terminated when the hydrolysis rate reached 95%. During this time, the oil phase substrate in the substrate circulation tank 2 was sampled periodically to measure the decomposition rate of the fat and oil and the amount of water in the oil phase. The decomposition rate of fats and oils is (acid value / saponification value) × 10
0 (%), and the water content is calculated using a water measurement device (AQUA
COUNTER AQ-7, manufactured by Hiranuma Sangyo Co., Ltd.).
The amount of water in the oil phase substrate in the substrate circulation tank 2 is 0.05-2.
1%. Table 1 shows the time required for each operation until the hydrolysis rate reaches 95% when this operation is performed four times.

[0017]

[Table 1]

Comparative Example 1 In Example 1, the pump 10 was not driven, the aqueous phase substrate was not sent to the oil / water mixing tank 4, and the inside of the substrate circulation tank 2 was rotated at 400 rpm.
A hydrolysis treatment was performed in the same manner as in Example 1 except that the mixture was stirred at m. The hydrolysis rate of fats and oils was calculated from the acid value of the oil phase when the oil-water mixture in the substrate circulation tank 2 was sampled and centrifuged at 1000 G for 5 minutes. Table 1 shows the time required for each cycle until the hydrolysis rate reaches 95%.

In Example 1, the required time hardly changed even if the number of times of processing was increased. However, in Comparative Example 1, the required time was longer as the number of times of processing was increased. It became longer.

Comparative Example 2 In Example 1, the oil-water mixing tank 4, the aqueous substrate supply line 7, and the reaction liquid / aqueous substrate mixed liquid return line 8 were not used.
The hydrolysis treatment was performed in the same manner as in Example 1 except that the end of the reaction solution discharge line 6 on the substrate circulation tank 2 side was located near the bottom of the substrate circulation tank 2. The decomposition rate of fats and oils was measured from the acid value of the oil phase in the substrate circulation tank 2. Table 2 shows the change over time in the hydrolysis rate at this time.

[0021]

[Table 2]

In Example 1, the hydrolysis rate was 9 after about 24 hours.
Although 5% was obtained, in Comparative Example 2, since the glycerin extraction of the reaction solution discharged from the enzyme tower 3 in the substrate circulation tank 2 was insufficient, the reaction was hardly inclined to the decomposition side, and the decomposition time was extremely long. It became longer.

[0023]

EFFECT OF THE INVENTION According to the method of the present invention, a stable hydrolysis of fats and oils over a long period of time is possible, with a degradation rate equivalent to that of a conventional hydrolysis method, without a decrease in enzyme activity due to an increase in the number of treatments. became.

[Brief description of the drawings]

FIG. 1 is an example of an apparatus for carrying out the oil / fat hydrolysis method of the present invention.

[Explanation of symbols]

 1: Device for hydrolysis of fats and oils 2: Substrate circulation tank 3: Enzyme tower 4: Oil / water mixing tank 5: Oil phase substrate extraction line 6: Reaction liquid discharge line 7: Water phase substrate supply line 8: Reaction liquid / water phase substrate mixing Liquid return line 9: Pump 10: Pump 11: Stirrer

Claims (5)

[Claims] 1. An oil phase substrate is sent from a substrate circulation tank to an enzyme tower filled with an enzyme-immobilized carrier, and the reaction solution passing through the enzyme tower is brought into contact with an aqueous phase substrate in an oil / water mixing tank. And then oil-water separation. 2. The method for hydrolyzing oils and fats according to claim 1, further comprising means for supplying an aqueous phase substrate from the substrate circulation tank to the oil / water mixing tank. 3. The water concentration in the oil phase substrate after oil / water separation,
The method for hydrolyzing fats and oils according to claim 1 or 2, wherein the saturation concentration is 5% by weight. 4. The method for hydrolyzing oils and fats according to claim 1, wherein the oil-water separation is carried out by standing separation and / or centrifugation. 5. The method according to claim 1, wherein the contact between the reaction solution and the aqueous phase substrate in the oil / water mixing tank is carried out by stirring and / or countercurrent contact. Disassembly method.