JPH07179882A - Antifreezing oil or fat and its production - Google Patents

Abstract

PURPOSE:To obtain an antifreezing oil or fat improved in low-temperature flow and oxidation stability by subjecting oil or fat containing mono- and diethylenic unsaturated fatty oil or fat containing a middle-chain saturated fatty acid to esterification or transesterification. CONSTITUTION:60-95 pts.wt. Oil or fat containing at least 80wt.%, based on the constituent fatty acids, 16C or higher mono- and diethylenic unsaturated fatty acids and 5-40 pts.wt. oil or fat containing at least 90wt.%, based on the constituent fatty acids, 6-12C middle-chain saturated fatty acids are transesterified in the presence of a lipase having a specificity for the positions 1 and 3 of a glyceride to obtain an antifreezing edible oil or fat containing at least 60wt.%, based on the constituent fatty acids, 16C mono- and diethylenic unsaturated fatty acids and 5-40wt.%, based on the constituent fatty acids at the positions 1 and 3 of the glyceride, 6-12C middle-chain saturated fatty acids.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an edible, freeze-resistant oil and fat having excellent oxidation stability, which is used as a lubricating oil for machines and a softening agent for resins which are required to have oxidation stability and low temperature fluidity.

[0002]

2. Description of the Related Art At present, mineral oil-based oil agents are widely used in oils required to have oxidation stability and low temperature fluidity, such as mechanical lubricating oils and softening agents for resins. But,
Mineral oils are difficult to decompose in the natural environment, and from the standpoint of global environmental protection, development of biodegradable oils is desired. In addition, especially in lubricating oils and softeners for resins used in the food field, it is desirable to use safer oil agents from the viewpoint of food hygiene, and it is desirable to develop freeze-resistant oils composed of edible materials. It is rare.

It has been well known that animal and vegetable fats and oils have physical properties as a lubricating oil and a softening agent for resins, although they are inferior in oxidative stability and low-temperature fluidity. Against this background, improvement of oxidative stability and low temperature fluidity has been studied in recent years for application of animal and vegetable fats and oils to lubricants and softeners for resins. For example, it has been attempted to use as a lubricating oil for food manufacturing machines by adding a sugar ester to a liquid oil such as rapeseed oil (Japanese Patent Laid-Open No. 5-3949).
7). Furthermore, the development of food machine lubricating oils using coconut oil as the main raw material has also been carried out by utilizing the transesterification technology (JP-A-4-314790, JP-A-4-31479).
1, JP-A-4-314792).

[0004]

As described above, biodegradable mechanical lubricating oils using animal and vegetable fats and oils as a main raw material are being actively developed, but compared with mineral oil type lubricating oils. There were problems with oxidative stability and fluidity at low temperatures. Palm oil,
The raw materials made of fats and oils such as beef tallow and hydrogenated oil that become solid at room temperature have relatively good oxidative stability, but have a high freezing point and fluidity at low temperatures cannot be expected. On the other hand, linseed oil,
Although oils containing a large amount of highly unsaturated fatty acids, such as fish oils, have excellent freezing resistance, they have problems with oxidative stability. In addition, as an animal and vegetable oil having a low freezing point and good oxidation stability,
There is a medium-chain saturated fatty acid triglyceride (hereinafter abbreviated as MCT), which is a glycerin ester derivative of hydrolyzed fatty acid of coconut oil or palm kernel oil, but MCT also has a freezing point higher than −15 ° C. and is not suitable in terms of low temperature fluidity. Was enough. From such a situation, under the winter environment, that is, −
There has been a demand for the development of an edible, freeze-resistant oil / fat capable of maintaining fluidity even when stored for a long period of time in a low temperature environment of 15 ° C. or lower and having improved oxidation stability.

[0005]

According to the present invention, an oil and fat containing monoene and diene unsaturated fatty acids having 16 or more carbon atoms and medium chain saturated fatty acids having 6 to 12 carbon atoms,
(1) 60% by weight or more of the constituent fatty acids are monoene and diene unsaturated fatty acids having 16 or more carbon atoms, and (2) medium chain saturated fatty acids having 6 to 12 carbon atoms at 1 and 3 positions of the glyceride, and 1 of glyceride. , 3 to 40% by weight of the constituent fatty acids, and (3) an edible, freeze-resistant oil and fat prepared by a transesterification reaction or an esterification reaction.

According to the present invention, by introducing a medium-chain saturated fatty acid having about 8 carbon atoms into an animal or vegetable oil or fat containing a large amount of unsaturated fatty acids of monoene and diene, it has safety as a food, and We have succeeded in developing an oil with improved oxidative stability that can maintain fluidity even at about -15 ° C. Since this oil is a glycerin ester, it has a function as a lubricating oil or a softening agent for resins as described above.

The raw materials for producing the fats and oils of the present invention, which will be described in detail below, are unsaturated fatty acids having 16 or more carbon atoms, such as palmitooleic acid, oleic acid and linoleic acid. It is possible to use animal and vegetable oils such that unsaturated fatty acids can account for 60% by weight or more of the constituent fatty acids of the target fats and oils, that is, most of general-purpose vegetable oils and part of animal oils, for example, rapeseed oil and soybean oil. , Safflower oil, sunflower oil, corn oil,
Examples include sesame oil, rice bran oil, cottonseed oil, peanut oil, olive oil, cold-pressed beef tallow oil, and cold-pressed lard oil. Of these, rapeseed oil, rice bran oil, which contains a relatively large amount of monoene unsaturated fatty acids,
Peanut oil, olive oil and the like are preferable, and rapeseed oil and rice bran oil are more preferable.

The medium-chain saturated fatty acid of the present invention has 6 to 1 carbon atoms.
An excellent effect can be exhibited in the range of 2, but fatty acids having 8 or 10 carbon atoms and mixtures thereof are particularly effective. Further, as the oil and fat containing them, there is MCT.

As a means for introducing a medium-chain saturated fatty acid into the above-mentioned animal and vegetable oils, a usual ester synthesis method can be used. A method of esterifying after decomposing into fatty acids,
There is a method of transesterifying fats and oils or fats and oils and fatty acids.

Of these, in the present invention, it is preferable to carry out a transesterification reaction between animal and vegetable oils and medium chain saturated fatty acids or their lower alcohol esters or glyceride oils and fats,
More preferably, the transesterification reaction is carried out specifically at the 1-position and 3-position of the glyceride. Examples of the lower alcohol ester mentioned here include esters of alcohols having 1 to 3 carbon atoms, and specific examples thereof include methanol ester, ethanol ester, n-propanol ester, isopropanol ester and the like.

When the method of transesterifying animal and vegetable oils and MCT is adopted, the former method has 1 carbon atom.
A glyceride oil containing 6 or more monoene and diene unsaturated fatty acids in an amount of 80% by weight or more, preferably 90% by weight or more of the constituent fatty acids, which is 60 to 95 parts by weight, the latter having 6 to 12 carbon atoms. It is a glyceride oil containing 90% or more of chain saturated fatty acids, and it is desirable to use 5 to 40 parts by weight of this.

The synthesized fats and oils can be directly used as a lubricating oil or the like. However, depending on the raw material oil and the synthesis method, subsequent purification treatments such as deoxidation and deodorization are used together. The fats and oils of the present invention introduced with medium chain saturated fatty acids by such a method are glyceride fats and oils containing monoene and diene unsaturated fatty acids having 16 or more carbon atoms and medium chain saturated fatty acids having 6 to 12 carbon atoms, 60% by weight or more of constituent fatty acids have 1 carbon atom
6 or more monoene and diene unsaturated fatty acids, and 5 to 40% by weight, preferably 10 to 20% by weight, of the constituent fatty acids at the 1,3 position of the glyceride are medium chain saturated fatty acids having 6 to 12 carbon atoms.

The fats and oils of the present invention provide an improvement in fluidity at low temperatures, that is, freezing resistance, which has not been observed when the above fats and oils are simply mixed. In other words, in the fatty acid composition of the oil / fat of the present invention, the monoene and diene unsaturated fatty acids having 16 or more carbon atoms are less than 60% by weight,
When the medium-chain saturated fatty acid having 6 to 12 carbon atoms is present in the 1-position and 3-position of the glyceride in an amount of less than 5% by weight or more than 40% by weight, the desired properties of the fat or oil of the present invention (-15 ° C) are obtained. The following fluidity) cannot be obtained.

Among the means for introducing medium-chain saturated fatty acids into the above-mentioned animal and vegetable oils, the medium-chain saturated fatty acids specifically at the 1- and 3-positions of glycerides are obtained by transesterification using a 1,3-position specific lipase. The most remarkable improvement in freezing resistance was observed for the oils and fats introduced with the above specified amount. This method is also preferable from the viewpoint of safety. Specifically, a known method disclosed in Japanese Patent Laid-Open No. 64-2588 may be used. However, in this case, in order to prevent the formation of by-products such as partial glycerides such as diglyceride and monoglyceride or free fatty acids, reaction conditions in which the water content in the reaction system is reduced as much as possible are desirable.

A more detailed description will be given by the following examples.

[0016]

【Example】

(Example 1) rapeseed 80 parts by weight of ODO (Nisshin Oil Mills Co. MCT, fatty acid composition _{C 8: 75%, C 10} : 2
Immobilized enzyme lipase PLG
The present invention is carried out by subjecting a hexane solution of the reaction product to hexane solution fractionation by silica gel column chromatography, using (manufactured by Meito Sangyo Co., Ltd.) at 50 ° C. for 20 hours. Samples of frozen resistant oil were prepared. Fractionation by a silica gel column was performed while checking the components of each fraction by gas chromatography. The following items were tested for this sample. 1) Measurement of fluidity by a bubble viscometer at -15 ° C and -20 ° C. 2) Measurement of cloud point. 3) Measurement of oxidative stability by the Rancimat method. (Ransimat method reference: MW Laubli et a
l, J. Amer. Oil Chem. Soc. 63
Vol., Page 792 (1986)).

Example 2 90 parts by weight of safflower oil and medium-chain mixed fatty acid triglyceride (hereinafter abbreviated as mixed MCT: fatty acid composition: C ₆ : 4%, C ₈ : 48%, C ₁₀ :
40%, C ₁₂ : 8%) 10 parts by weight are mixed and lipase F (manufactured by Manville Co.) immobilized on Celite (manufactured by Amano Pharmaceutical Co., Ltd.) is used at 40 ° C. for 30 hours to prepare 1,3 of glyceride. A transesterification reaction was performed at the position, and the same purification treatment as in Example 1 was performed. The same test as in Example 1 was performed on this sample.

(Example 3) 80 parts by weight of rapeseed oil and ODO
(Nisshin Oil Co., Ltd. MCT, fatty acid composition is C ₈ : 75
%, C ₁₀ : 25%) and mixed with 0.1% sodium methylate at 80 ° C. for 30 minutes to carry out a random transesterification reaction. The same test as in Example 1 was performed.

(Example 4) 80 g of rapeseed oil fatty acid, 15 g of caprylic acid, 5 g of capric acid and 35 g of glycerin were added.
After reacting at 150 ° C. for 8 hours in the presence of a toluenesulfonic acid catalyst, the sample was prepared by deoxidizing with NaOH and purifying in the same manner as in Example 1. The same test as in Example 1 was performed on this sample.

(Example 5) 95 parts by weight of rapeseed oil and ODO
(Nisshin Oil Co., Ltd. MCT, fatty acid composition is C ₈ : 75
%, C ₁₀ : 25%) and mixed with each other using the immobilized enzyme lipase PLG (manufactured by Meito Sangyo Co., Ltd.) to conduct transesterification reaction of 1,3-position of glyceride. A sample was prepared by performing a purification treatment in the same manner. The same test as in Example 1 was performed on this sample.

Comparative Example 1 95 parts by weight of rapeseed oil and ODO
(Nisshin Oil Co., Ltd. MCT, fatty acid composition is C ₈ : 75
%, C ₁₀ : 25%) 5 parts by weight, and the same test as in Example 1 was performed on this sample.

(Comparative Example 2) 50 parts by weight of rapeseed oil and ODO
(Nisshin Oil Co., Ltd. MCT, fatty acid composition is C ₈ : 75
%, C ₁₀ : 25%) and mixed with 0.1% sodium methylate at 80 ° C. for 30 minutes to carry out a random transesterification reaction on the sample, which was the same as in Example 1. Treated and tested.

The fatty acid composition of rapeseed oil, safflower oil, the fats and oils of Examples 1 to 5 and the fats and oils of Comparative Examples 1 and 2 used as raw materials for obtaining the edible and freeze-resistant fats and oils of the present invention were analyzed by gas chromatography. analyzed. The results are shown in Table 1.

[0024]

[Table 1]

[0025]

[Table 2] As is clear from the above results, the oil / fat of the present invention is -15
Although it had excellent fluidity even at ° C, the fats and oils of Comparative Examples 1 and 2 were solidified and could not be used.

[0026]

EFFECTS OF THE INVENTION By introducing a medium-chain fatty acid having about 8 carbon atoms into the 1,3-positions of glycerin in a vegetable oil containing a large amount of mono- and diene unsaturated fatty acids, it is safe as a food and at a low temperature. In the above, a glyceride oil / fat having improved oxidation safety capable of maintaining excellent fluidity was obtained.

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Claims (2)

[Claims] 1. An oil and fat containing a monoene or diene unsaturated fatty acid having 16 or more carbon atoms and a medium chain saturated fatty acid having 6 to 12 carbon atoms, wherein (1) 60% by weight or more of the constituent fatty acids has 16 or more carbon atoms. Which is a monoene and diene unsaturated fatty acid of (2) containing 5-40% by weight of a medium-chain saturated fatty acid having 6 to 12 carbon atoms in the 1,3 position of the glyceride, and a constituent fatty acid of the 1,3 position of the glyceride, And (3) an edible freezing-resistant fat or oil, which is prepared by a transesterification reaction or an esterification reaction. 2. Oils and fats 60 to 95 containing 80% by weight or more of monoene and diene unsaturated fatty acids having 16 or more carbon atoms.
90 parts by weight of parts by weight and medium-chain saturated fatty acid having 6 to 12 carbon atoms
The method for producing fats and oils according to claim 1, wherein 5 to 40 parts by weight of the fats and oils contained above are subjected to a transesterification reaction with a lipase having specificity at the 1-position and 3-position of the glyceride.