JPH0458315B2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field The present invention uses palm oil, which is a solid fat, as a raw material.
This invention relates to a method for producing salad oil, which is a useful liquid oil.

Solid fats that are solid at room temperature have many inconveniences in use. Therefore, it is common practice to convert it into liquid oil. For example, in edible oils such as salad oil and tempura oil, liquid oils are usually used, and solid fats are not actually used.

In addition, solid fats such as hydrogenated oil, palm oil, lard, and beef tallow are sometimes used for food processing and frying in stores, but these often have poor frying stability, flavor, odor, and price. Based on the reason, it goes without saying that the liquid oil method is much more convenient in terms of workability.

The same thing can be said about industrial oils and fats.

On the other hand, solid fats such as palm oil have been produced in large quantities in recent years and are expected to increase in the future, and therefore there is a strong desire to develop new and useful uses for them. However, as they are solid fats, their uses are naturally limited.

Therefore, from this point of view, it would be extremely meaningful if we could produce salad oil from palm oil, which is a solid fat, that is versatile as a household edible oil, the demand for which has been increasing in recent years, and that also has high commercial value. Needless to say.

(b) Prior Art Various attempts have been made to liquefy solid fats.

The simplest method is to simply mix solid fat with liquid oil, but the amount of solid fat that can be blended is extremely small in order to produce the desired liquid oil, so it is not an effective method. It was something I couldn't do.

In addition, a method is known in which solid fat is fractionated to produce a low melting point fraction, but as is clear from the example of fractionated olein from palm oil, even the low melting point fraction tends to become solid in the summer. As a result, at best, only a semi-liquid oil could be obtained.

Therefore, it is possible to further separate this low melting point portion, but the yield of liquid oil is low, and furthermore, it was impossible to expect a liquid oil with cooling resistance comparable to that of salad oil.

Furthermore, multi-stage processing consisting of directional transesterification and fractionation using metallic sodium or sodium methylate, and combinations thereof, is known as a method for producing liquid or semi-liquid oil from palm oil (EWEckey, USP 2442531). (1944);
2442531 (1944); VJ Baltes, Fette Seifen
Anstrichmittel, 77, 41 (1975).

However, such a process is complicated and has a low yield, making it difficult to carry out industrially.

Furthermore, as a special example, a method is known in which palm oil is transesterified with an alkyl ester and then fractionally distilled. (L.Koslowsky, Oleagineux, 30(5)
221 (1975)). However, this method was also completely impractical. In addition, methods using this type of chemical transesterification reaction have problems with their handling, such as being dangerous, as the catalyst used in the reaction is a special one, and it is natural that the catalyst may be used after the reaction. Since it has to be removed by washing with water, it has various drawbacks, such as problems with wastewater (pollution control), and therefore, this method is completely unfeasible from an industrial perspective.

In view of the above-mentioned circumstances, various methods based on transesterification using lipase have been proposed in recent years. However, no industrially effective method for converting solid fat into liquid oil has been proposed so far.

For example, JP-A-52-104506 discloses transesterification of palm oil or its intermediate fraction with stearic acid using lipase.
Its purpose is to provide a cacao substitute fat at most, and of course does not provide the salad oil that is the object of the present invention. In addition, it states that a solvent is used during transesterification, oil recovery, and separation, and the reaction temperature in each specific example is also relatively low.

Furthermore, JP-A-59-198798 proposes transesterification of deodorized palm fractionated fat and soybean oil in a closed container in the presence of a surfactant, but an organic solvent is used and the reaction temperature is also relatively low;
What is obtained is about the same as cacao substitute fat.

This can also be said about JP-A-57-111398 filed by the same applicant.

In short, the common things that can be said about this type of known technology using organic solvents are that they require the use of airtight containers, recovery of the solvent, and other incidental matters, and there are various difficulties in terms of equipment and cost. I couldn't avoid it.

Furthermore, when different components, such as surfactants and sugars, are present in the transesterification reaction, there is a problem in that a post-treatment step must be added to remove them after the reaction.

In addition, performing transesterification in batches requires a recovery process for reusing the lipase, and furthermore, when producing liquid oil by fractionation, it is difficult to effectively utilize the solid fat that is produced as a by-product. Otherwise, it would be disadvantageous in terms of cost.

(c) Problems to be Solved by the Invention Therefore, the purpose of the present invention is to improve or eliminate the various difficulties mentioned above and to provide a method for efficiently producing salad oil, which is a liquid oil, from palm oil, which is a solid fat. It is about providing.

(d) Means for Solving the Problems In view of the current situation, the present inventors conducted intensive research and found that transesterification is carried out under specific conditions, and then the reaction product is fractionated (more preferably, by It has been found that the above-mentioned objects of the invention can be achieved (by recycling the living organisms).

The present invention was completed based on this knowledge.

That is, using an immobilized lipase that has 1,3-specificity and an optimum temperature of about 70°C, heat-melted palm oil and odorless liquid raw material oil are transesterified in the absence of a solvent, and then the reaction is carried out. The present invention relates to a method for producing salad oil, which comprises fractionating the product in an oil solvent. One aspect of the present invention is to further enhance the effect by recycling the solid fat obtained by fractionation after transesterification.

The present invention will be explained in more detail below. First, in the present invention, an immobilized lipase having 1,3 specificity and an optimum temperature of 70°C is used.

Such immobilized lipases include, for example, Novo
An example of this is NOVO3A immobilized lipase from Co., Ltd.

This one is called Mucor Mihai.
It is a lipase with 1,3-specificity derived from Miehei), which is immobilized using an ion exchange resin as a carrier.

In addition, in the present invention, Pseudomonas flagi 22.39B described in Japanese Patent Publication No. 56-28517
(Pseudomonas fragi22/39B)-derived lipase,
Lipase A produced by Pseudomonas mephiticavar.lipolytica described in Japanese Patent Publication No. 50-25553, and lipase A derived from Rhizopus niveus described in Example 2 of U.S. Patent No. 4,420,560. A carrier in which lipase or the like is immobilized can be used.

The present inventors first conducted various studies on the catalytic ability of transesterification reactions, especially the catalytic ability of lipase, on various systems consisting of palm oil and liquid raw material oil, and found that 1 such as Candida cylindracea. The transesterification reaction using a lipase that does not have 3-specificity has a higher tendency to retain salad oil than the transesterification reaction product using a lipase that has 1,3-specificity due to the crystallinity of the filtration fraction in winter. was found to be low. Therefore, in the present invention, a lipase having 1,3 specificity is used.

Furthermore, the optimum temperature of the immobilized lipase used in the present invention, about 70°C, is extremely high considering that the temperature of conventionally used lipases is around 40°C at most.

This means that when the transesterification reaction is carried out near the optimum temperature, the reaction can be completed at a faster reaction rate than could be achieved using conventional methods, and that the equilibrium point is determined by the product system. (means high reaction efficiency).

Furthermore, with conventional enzyme catalysts, when the reaction temperature is raised, the reaction rate increases, but the possibility of thermal denaturation (deactivation) of the enzyme (protein) also increases, but the present invention No such thing will happen.

Next, in the present invention, "palm oil" is used as the solid fat.

Furthermore, in the present invention, "liquid raw material oil", particularly odorless liquid raw material oil, is used. Such odorless liquid raw material oils include soybean oil, cottonseed oil, rapeseed oil, corn oil,
Examples include safflower oil, rice oil, and sunflower oil. These act as solvents for the palm oil and therefore, in the process of the invention, there is no need for the addition of solvents, as is done in conventional processes.

Further, both oil components used in the present invention may be deoxidized oil, bleached oil, or deodorized oil. In addition, the blending ratio of palm oil and liquid raw material oil used in the present invention is such that the purpose of the present invention is to obtain a liquid oil that has cooling resistance that satisfies the standards for salad oil (Japanese Agricultural Standards, no clouding for 5.5 hours at 0°C). Because it is in the manufacturing of
The ratio is 5-50:95-50, preferably 30-50:70-50.

By transesterifying a mixture having the above-mentioned mixing ratio, it is possible to produce salad oil with a sufficiently satisfactory yield while maintaining practical economic efficiency.

That is, if a mixture in which the amount of palm oil exceeds 50% to 50% of liquid raw material oil is used as a raw material, salad oil cannot be recovered with a satisfactory yield in the subsequent fractionation step. Note that salad oil can be produced more economically if the amount of palm oil is 30 or more based on the liquid raw material oil 70.

The transesterification reaction of the present invention is carried out at about 60 to 80°C, particularly around 70°C.

In order to increase the reaction (ester exchange reaction) rate, it is common sense that a high temperature is desirable. However, if it is too high, problems of inactivation of this type (in biochemical reactions) occur.

The present invention relates to a novel method that rationally solves the seemingly contradictory problems described above.

In the present invention, it is also desirable that the homogeneous mixture of oils be adjusted to contain water that is saturated at the reaction temperature.

In this way, the content of free fatty acids produced by-product during the reaction can be kept low. In addition, the activity of immobilized lipase can be maintained for a very long time.

Furthermore, the transesterification used in the present invention can be carried out either batchwise or continuously. but,
A continuous method using a column filled with immobilized lipase is better from the viewpoint of equipment and efficiency.

That is, in the batch method, in order to allow the reaction to proceed sufficiently, solid fats in particular must be heated at a relatively high temperature for a long period of time, and the amount of free fatty acids produced by hydrolysis as a side reaction increases.

On the other hand, in the continuous method, the heating time is short and the amount of by-product fatty acids can be kept low, so it is preferable to employ the continuous method in the present invention.

In the present invention, the solid fat content is further separated from the modified product thus produced by fractionation.

Fractionation is performed without solvent. One of the features of the present invention is that it is carried out without a solvent. To obtain salad oil (which does not become cloudy for 5.5 hours at 0°C according to the Japanese Agricultural Standards), which is the target product of the present invention, 3.
The solid components in the reaction product are precipitated by cooling to ~10° C., preferably about 5° C., and the solid fat components are filtered and fractionated by a conventional method.

At this time, the by-produced solid fat is used together with the originally used liquid oil or another liquid oil, or the by-produced solid fat and palm oil are combined and recycled. That is, one of the different features of the present invention is that the by-product solid fat is recycled and used.

Hereinafter, the present invention will be specifically explained with reference to Examples.

(e) Examples Example 1 Blend 40% palm oil and 60% soybean oil and heat at 70℃.
Inner diameter filled with 16.2g of immobilized Reverse NOVO3A
Transesterification was carried out by passing the liquid through a 1.5 cm column at a flow rate of 32 g/hour. Cut off the reactants from the initial 72 hours and obtain about 5 kg of the reactants after that (softening point
After drying, the mixture was slowly cooled to 5°C over 48 hours, and the precipitated crystals were filtered off at the same temperature. The liquid oil yield was 82%, and when the liquid oil was cooled in ice water at 0°C, it did not become cloudy until 22 hours later, and had sufficient cooling resistance as salad oil.

As a comparison, a product containing 40% palm oil and 60% soybean oil had a softening point of 22.55°C, making it completely impossible to slowly cool and winterize it.

Example 2 Blending 40% palm oil and 60% rapeseed oil, Example 1
Obtain transesterified oil in exactly the same manner as (softening point
After drying, the mixture was slowly cooled to 5°C over 48 hours, and the precipitated crystals were filtered off at the same temperature.

The liquid oil yield was 86%, and the liquid oil had a cooling resistance of 25 hours, which was sufficient for use as a salad. This liquid oil 70%, vinegar 10%, egg yolk 10%,
Mayonnaise was prepared using a conventional method using salt, pepper, and a little mustard, and stored in a home refrigerator for 3 months, but no demulsification was observed, confirming that it can be used as salad oil.

As a comparison, a product containing 40% palm oil and 60% rapeseed oil had a softening point of 22.0°C, making it completely impossible to slowly cool and winterize it.

Example 3 In Example 1, transesterification was subsequently performed and the reaction product was winterized to collect about 2 kg of stearin as a by-product. The softening point of this stearin is 23.4
It was warm at ℃. 2 kg of palm oil, 2 kg of stearin, and 6 kg of soybean oil were heated and melted, and 40% palm oil and soybean oil were added to the column packed with the immobilized enzyme used in Example 1.
Following the transesterification of 60% of the blended oil, these three blends were passed through at the same flow rate at 70°C.

Approximately 5 kg of this transesterified oil was obtained (softening point 5.1).
After drying, the mixture was slowly cooled to 5°C over 48 hours, and the precipitated crystals were filtered off at the same temperature. The liquid oil yield was 88%, and the liquid oil had a cooling resistance of 25 hours, which was sufficient for a salad oil. In addition, the softening point of the stetalin by-produced at this time is
It was 23.2℃.

Example 4 Immobilized lipase NOVO3A used in Example 1
Instead, 1 part by weight of the lipase derived from Pseudomonas flagi 22.39B described in Japanese Patent Publication No. 56-28517 was mixed with 3 parts by weight of ion-exchanged water and 2 parts by weight of Celite, and the mixture was dehydrated under reduced pressure at 30°C or less. Immobilized lipase was obtained. 10 parts by weight of the above immobilized lipase was added to a raw material oil containing 30% palm oil and 70% soybean oil, and the mixture was stirred at 65 to 75°C for 10 hours to carry out a transesterification reaction. The immobilized lipase was removed from 5 kg of the reaction product, and after drying, it was fractionated in the same manner as in Example 1 without solvent. The liquid oil yield was 90% and the liquid oil had a body cooling property of 25 hours.

(f) Effect of the invention The effects of the present invention are listed below.

() The reaction (ester exchange reaction) is fast and the yield of salad oil obtained is high.

() The resulting salad oil has a cooling resistance that is sufficiently acceptable in the market.

() No specific pre-treatment or post-treatment is substantially required, and the transesterification reaction is carried out continuously;
can become. In other words, maintenance costs etc. can be significantly reduced.

Claims (1)

[Scope of Claims] 1. Palm oil: A homogeneous mixture of odorless liquid raw material oil (weight ratio) of 5:95 to 50:50, which has a 1.3 specificity. A method for producing salad oil, which comprises transesterifying without a solvent using an immobilized lipase whose optimum temperature is about 70°C, and then fractionating the product without a solvent. 2. The method for producing salad oil according to claim 1, wherein the palm oil contains solid fat obtained by fractionation without a solvent. 3. Claim 1, wherein the odorless liquid raw material oil is at least one of oils that are liquid at room temperature, such as soybean oil, cottonseed oil, rapeseed oil, corn oil, rice oil, sunflower oil, and safflower oil. The method for producing the salad oil described. 4. The method for producing salad oil according to claim 1, wherein the immobilized lipase is an immobilized lipase derived from Mucor mihai. 5. The method for producing salad oil according to claim 1, which comprises carrying out the transesterification in a packed column. 6. The method for producing salad oil according to claim 1, wherein the transesterified product is cooled to 3 to 10°C without a solvent and fractionated by filtration.