JPS58126794A - Hydrolytic method of fat or oil with lipase - Google Patents

Abstract

PURPOSE:To hydrolyze continuously a fat or oil, by raising the fat or oil introduced into an aqueous solution of lipase in the form of oil droplets naturally by utilizing the specific gravity difference between water and the fat or oil. CONSTITUTION:A fat or oil having a smaller specific gravity than water usually at 10-45 deg.C and at the melting point of the fat or oil or above is injected from a small hole at the bottom of a vertical column filled with an aqueous solution of lipase, preferably >=50units/ml water, particulary >=200units/ml water, concentration as fine oil droplets, introduced into the column and then raised naturally by the specific gravity difference from water.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for hydrolyzing fats and oils using lipase.

The conventional method for hydrolyzing fats and oils using lipase is to mix low melting point fats and oils in liquid form with an aqueous lipase solution and carry out the hydrolysis reaction while stirring, and for high melting point fats and oils, use semi-solid emulsification by mixing with a lipase aqueous solution. A method is adopted in which the hydrolysis reaction is carried out in a slurry state, and both methods are batch methods.

However, at present, industrial fatty acid production methods, such as high-pressure hydrolysis of fats and oils, hydrogenation, distillation of fatty acids, and solid-liquid separation of fatty acids, are all continuous processes, so only the hydrolysis of fats and oils is carried out using lipases as described above. Even if a batch reaction is carried out, there is a drawback that it cannot be connected to the current continuous production line.

In general enzyme reactions, a method of continuously passing an aqueous solution of a substrate through a column packed with an immobilized enzyme is known as a method for carrying out the enzyme reaction continuously on an industrial scale.

However, in this method, since the substrate must be water-soluble, the above method cannot be directly applied when the substrate is a hydrophobic oil or fat that is immiscible with water. If this were to be applied, it would be possible to prepare a water-containing organic solvent solution or emulsion of oil and fat and introduce it into a column packed with immobilized enzymes, but in this case, the use of organic solvents and emulsifiers would complicate the reaction system. In addition, there are problems in that the above-mentioned use exerts an inhibitory effect on the enzymatic reaction and complicates the separation process of the product. In addition, in such an immobilized enzyme packed column method, a relatively expensive immobilization carrier is required for immobilizing the enzyme, and the immobilization operation is complicated, and the activity of the enzyme is significantly reduced due to immobilization. It has many drawbacks such as (7).

From the above-mentioned viewpoint, the inventors have developed a method in which lipase, which is an enzyme that hydrolyzes fats and oils, is brought into contact with fats and oils in an aqueous solution state without using an immobilized enzyme packed column method, and the hydrolysis can be carried out continuously. As a result of intensive study, we have finally completed this invention.

That is, the present invention relates to a method for hydrolyzing fats and oils using lipase, which is characterized by carrying out a hydrolysis reaction while allowing fats and oils introduced in the form of oil droplets into an aqueous lipase solution to float naturally.

The method of the invention can be carried out analogously. First, from the bottom of a vertical column filled with an aqueous lipase solution, fats and oils with a specific gravity lower than that of water are injected through pores and introduced in the form of small oil droplets, which are naturally floated due to the difference in specific gravity with the water. At this time, many oil droplets with a large specific surface area come into sufficient contact with the lipase aqueous solution in the process of floating, and are hydrolyzed into fatty acids and glycerin by an enzymatic reaction. Since the generated fatty acids are separated on the surface of the lipase aqueous solution and chrycerin is dissolved in the lipase aqueous solution, the fatty acids and chrycerin are completely separated.

The type of lipase used in this invention is not particularly limited, but in general, lipases sourced from microorganisms such as Candida, Chromobacterium, Aspergillus, Penicillium, Geotrichum, and Rhizopus, pancreatic, etc. Lipase obtained from animal organs, lipase obtained from plant seeds such as castor seeds, etc. can be used.

The concentration of the lipase aqueous solution is not particularly limited and can be selected freely, and the higher the concentration, the faster the hydrolysis reaction proceeds. From a practical point of view, it is recommended that the above concentration is 50 units/d water or more, especially 200 units/d water.
It is preferable that the me water is above the water.

In the case of ordinary lipase, the temperature for the hydrolysis reaction of fats and oils is generally 10 to 10% from the viewpoint of both prevention of deactivation and reaction rate.
It is preferable that the temperature is in the range of 45°C and higher than the melting point of the oil or fat. (7) However, for thermostable lipases, a higher temperature than the above can be applied to improve the hydrolysis reaction rate.

The substrate fats and oils include those having a melting point below the hydrolysis reaction temperature, that is, when using ordinary lipase, fats and oils with a melting point of about 40°C or below, such as vegetable oils such as olive oil, linseed oil, safflower oil, soybean oil, Animal fats such as tung oil, lard, and fish oil can be used. When using heat-stable lipase, palm oil, beef tallow, etc. can also be used.

This oil is introduced into the lipase aqueous solution in the form of oil droplets by appropriate means such as discharging it through pores, and the size of the oil droplets is generally 0.5-5cm in diameter, preferably 1-3fi.
It is. The oil in the form of oil droplets thus introduced is fully contacted with the lipase aqueous solution and hydrolyzed while it floats naturally. The contact time can be adjusted as appropriate by adjusting the size of the oil droplets, the length of the column, and the installation of baffles, etc., or by sequentially passing through multiple columns filled with an aqueous lipase solution.
The contact time can be increased by recycling the floating material and repeatedly passing it through the lipase aqueous solution.

By this method, fats and oils can be hydrolyzed to a hydrolysis rate of 98% or more, and the resulting fatty acids can be used as raw materials for distillation. Furthermore, depending on the intended use of the fatty acid, it is also possible to set conditions such that the reaction is stopped at an appropriate hydrolysis rate.

As detailed above, the present invention utilizes the difference in specific gravity between water and fat to carry out a hydrolysis reaction while naturally floating the fat introduced in the form of oil droplets into an aqueous lipase solution. By continuously introducing , the outstanding effect of providing a continuous hydrolysis method using lipase that is compatible with industrial fatty acid production methods can be obtained.

Furthermore, the above-mentioned method of the present invention can be applied to conventional batch processes such as a method of mixing a low-melting point oil and a lipase aqueous solution in a liquid state or a method of mixing a high-melting point oil and a fat with a lipase aqueous solution and reacting in a semi-solid slurry state. Unlike the conventional method, it does not require strong stirring energy when contacting the oil and fat with the lipase aqueous solution, and it also eliminates the various problems associated with enzyme immobilization and the use of organic solvents and emulsifiers, such as the immobilized enzyme packed column method. There is no risk of causing any problems associated with this.

In addition, the hydrolysis reaction does not require strong stirring as mentioned above, which reduces oxidative deterioration of fats and oils due to entrained air, and the reaction temperature is usually kept at a low temperature of 40°C or less, making it suitable for high-pressure hydrolysis. There is no problem of thermal deterioration, and the quality of the fatty acids obtained is much better than that of any conventional hydrolysis method.

The principle of the hydrolysis method of this invention, that is, the method of introducing the substrate in the form of oil droplets into an aqueous enzyme solution using the difference in specific gravity between water and the substrate and causing the enzyme reaction to float while floating the substrate, is based on the principle of the hydrolysis method of this invention. It can be said that it can be widely applied to various hydrophobic substrates other than those described above, and also to enzyme reactions other than hydrolases.

Finally, examples of the present invention will be explained in comparison with comparative examples. In the following Examples and Comparative Examples, olive oil was used as the substrate oil and lipase powder obtained from a culture solution of Candida cylindracea was used as the lipase.

In addition, the hydrolysis rate shown below is calculated by performing a ζ sampler at predetermined time intervals in the hydrolysis reaction, dehydrating it, measuring the saponification value and acid value, and using the following formula.

Example 1 A column with a height of 100 cm was filled with an aqueous solution containing lipase at 500 units/me water, maintained at 37°C, and purified olive oil was discharged from the bottom of the column through the tip of a syringe needle with an outer diameter of 0.5 fl. (Saponification value 192.4, acid value 0.
2, iodine value 82) was introduced as oil droplets with a diameter of 2.5 to 3 mm. The space velocity at which the introduced oil droplets float is 0.47
/ It was time. When the relationship between the contact time of the lipase aqueous solution and the oil droplets and the hydrolysis rate was investigated using a method in which the floated particles were recycled again, the results shown by curve 8 in the figure were obtained. As is clear from this, according to the above method, a hydrolysis rate of 96.7% was obtained in 42 minutes, indicating that contact between the oil droplets and the lipase aqueous solution was carried out extremely well.

Comparative Example 500 units/-50 units of lipase aqueous solution and Example 1
The same refined olive oil used in 502 and 200
The mixture was placed in an Erlenmeyer flask, and a batch hydrolysis reaction was carried out while maintaining the temperature at 37° C. and stirring with a magnetic stirrer. When we investigated the relationship between the stirring time, that is, the contact time between the lipase aqueous solution and the substrate, and the hydrolysis rate, we found that the curve in the figure -
The results shown in B were obtained. As is clear from this, it was confirmed that according to the above method, 280 minutes were required to obtain a hydrolysis rate of 96%, and the reaction time was approximately 6.7 times that of Example 1.

Example 2 A hydrolysis reaction of purified olive oil was carried out in the same manner as in Example 1, except that an aqueous solution containing lipase of 1.000 units/- of water was used. As a result, a hydrolysis rate of 96% was achieved in 34 minutes.

That is, by doubling the lipase concentration, the hydrolysis rate could be improved 1.24 times.

Example 3 A hydrolysis reaction of refined olive oil was carried out in the same manner as in Example 1, except that an aqueous solution containing lipase at 5,000 units/me of water was used. As a result, a hydrolysis rate of 96% was achieved in 20 minutes.

That is, by increasing the lipase concentration by 10 times, the hydrolysis rate could be improved by 2.1 times.

[Brief explanation of the drawing]

The drawing is a characteristic diagram showing the relationship between the contact time of the lipase aqueous solution and the substrate olive oil and the hydrolysis rate. Curve-A: Hydrolysis method of this invention (Example 1) Curve-B: Conventional hydrolysis method (Comparative example) Patent applicant: NOF Corporation

Claims (1)

[Claims] (1) A method for hydrolyzing fats and oils using lipase, which is characterized by carrying out a hydrolysis reaction while naturally floating the fats and oils introduced in the form of oil droplets into an aqueous lipase solution.