JPH04261497A - Purification of oil and fat rich in diglyceride - Google Patents

Abstract

PURPOSE:To obtain edible oil and fat rich in diglyceride and improved in taste in good yield by adding an organic acid to oil and fat rich in diglyceride and then subjecting the oil and fat to deodorizing treatment. CONSTITUTION:(B) 0.1-2 pts.wt. organic acid such as citric acid, succinic acid, maleic acid, oxalic acid, aconitic acid, itaconic acid, citraconic acid, tartaric acid, fumaric acid or malic acid is added to (A) 100 pts.wt. oil and fat rich in diglyceride and then as necessary the mixture is subjected to decoloring treatment with a porous absorbent and further cleaned with water containing a lower alcohol and then subjected to deodorizing treatment by steam distillation.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a method for refining fats and oils rich in diglycerides, and more particularly, the present invention relates to a method for refining fats and oils rich in diglycerides, and in particular, a purification method capable of improving flavor and obtaining fats and oils rich in diglycerides suitable for eating without causing disproportionation reactions. Regarding the method.

0002

[Prior Art and Problems to be Solved by the Invention] Conventional general methods for refining oils and fats are related to oils and fats mainly composed of triglycerides such as soybean oil, corn oil, rapeseed oil, palm oil, and fish oil. There has been little study on purification.

[0003] Diglyceride is glycerin with two fatty acids ester-bonded and has one hydroxyl group as a functional group. Because it has hydroxyl groups, disproportionation reactions between diglyceride molecules tend to occur at high temperatures, resulting in an increase in monoglyceride and triglyceride, and a decrease in the target diglyceride.

0004

[Means for Solving the Problems] Under these circumstances, the present inventors have developed a method for refining fats and oils rich in diglycerides.
By adding an organic acid, the disproportionation reaction of diglyceride is suppressed in the deodorizing process by steam distillation, and by washing with an aqueous solution of an organic acid or an aqueous solution containing an organic acid and a lower alcohol, the deodorizing process by steam distillation can be suppressed. The present inventors have discovered that the disproportionation reaction of diglyceride is suppressed in the method, and have completed the present invention.

That is, the present invention provides a method for purifying fats and oils rich in diglycerides, which comprises adding an organic acid to fats and oils rich in diglycerides, and then deodorizing the fats and oils rich in diglycerides. The present invention provides a method for purifying fats and oils rich in diglycerides, which comprises washing with water containing organic acids or water containing organic acids and lower alcohols, followed by deodorizing treatment by steam distillation.

[0006] The diglyceride used in the present invention includes diglyceride with a single acid group as a constituent fatty acid or a mixed acid group diglyceride with two or more types of constituent fatty acids. The constituent fatty acids may be either straight chain and/or branched fatty acids, and may be saturated and/or unsaturated fatty acids. Although the chain length of the constituent fatty acids is not particularly limited, those having 8 to 22 carbon atoms can be exemplified as commonly used ones. In addition, the positions where the constituent fatty acids form ester bonds with glycerin are α-position,
It doesn't matter which position is β.

[0007] The diglyceride-rich fats and oils referred to in the present invention are particularly characterized in that the diglyceride content is 30% of the total glyceride content.
It is preferable that the amount is at least % by weight. Such diglyceride-rich fats and oils can be produced by esterification of fatty acids and glycerin, transesterification of fats and oils and glycerin, etc., but the present invention is not limited by the production method, purification method, or history of the diglyceride-rich fats and oils. .

[0008] The organic acids used in the present invention preferably have chelating ability, and specific examples include citric acid, succinic acid, maleic acid, oxalic acid, aconitic acid, itaconic acid, citraconic acid, tartaric acid, fumaric acid, and apple acid. Examples include acids. The general method for adding organic acids is to add them as water or an aqueous solution containing lower alcohols, and then remove the water and lower alcohols by heating, reducing pressure, etc.; It may also be dissolved in rich fats and oils.

[0009]Although there is no limit to the amount of organic acid added, it is preferably 0 to 100 parts by weight of diglyceride-rich fats and oils.
．． 1 to 2 parts by weight.

The refining method of the present invention can be combined with conventional methods for refining fats and oils. That is, the step of adding an organic acid or the step of washing with water containing an organic acid or water containing an organic acid and a lower alcohol can be combined with the conventional oil and fat purification step. Examples of these combinations include the methods shown below.

(1) A method in which an organic acid is added to fats and oils rich in diglycerides and then deodorized by steam distillation. (2) A method in which organic acids are added to fats and oils rich in diglycerides, decolorized using a porous adsorbent, and then deodorized by steam distillation. (3) A method in which organic acids are added to fats and oils rich in diglycerides, followed by decolorization using a porous adsorbent, washing with water or water containing lower alcohols, and deodorization by steam distillation. (4) A method in which fats and oils rich in diglycerides are washed with water containing an organic acid, or water containing an organic acid and a lower alcohol, and then deodorized by steam distillation.

In the present invention, when oils and fats rich in diglycerides are washed with water containing an organic acid or water containing an organic acid and a lower alcohol, the concentration of the organic acid is 1 to 50% of the water or water containing the lower alcohol. Weight percent is preferred. The amount of water containing an organic acid or water containing an organic acid and a lower alcohol to be added is preferably 1 to 1000 parts by weight per 100 parts by weight of diglyceride-rich fat or oil.

[0013] Furthermore, in the cleaning in the method of the present invention, the operation of thoroughly mixing diglyceride-rich fats and oils with water containing an organic acid, or water containing an organic acid and a lower alcohol, and then repeating the operation of removing the water or lower alcohol. To do something. Examples of lower alcohols used here include methanol, ethanol, propanol, isopropanol, and the like. The cleaning temperature may be at least the melting point of the diglyceride-rich fat or oil, but it is preferably carried out at a temperature of 25 to 95°C.

[0014] In the present invention, the temperature of the deodorizing treatment by steam distillation may be lower than 220°C without any particular problem, but if it is desired to improve the flavor of the refined diglyceride-rich oil or fat, the temperature should be 220°C or higher. is desirable. The method for deodorizing by steam distillation may be a batch method, a semi-continuous method, a continuous method, or a thin film continuous method. The amount of water vapor is preferably 1 to 20 parts by weight, more preferably 3 to 10 parts by weight per 100 parts by weight of the diglyceride-rich fat or oil.

[0015] In this way, fats and oils rich in diglycerides can be obtained without reducing the diglyceride content and with good flavor.

[0016]

EXAMPLES The present invention will be explained in detail below with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples.

Example 1 An esterified product obtained by esterifying a fatty acid derived from rapeseed oil with glycerin was subjected to molecular distillation to remove fatty acids and monoglycerides. Furthermore, 6 g of activated clay and 2 g of activated carbon were added to 300 g of this material, and the mixture was heated at 110°C for 50 minutes.
After performing a decolorization treatment using a torr for 30 minutes, white clay and activated carbon were removed by filtration to obtain decolorized oil and fat. Furthermore, 40 g of distilled water was added to 200 g of this decolorized oil and fat, and the mixture was stirred at 40° C. for 10 minutes, and then the aqueous phase was removed by decantation. This water washing process was repeated twice to obtain fats and oils rich in diglyceride. 7.5 g of a 10% citric acid aqueous solution was added to 150 g of this diglyceride-rich fat and oil, and the mixture was stirred at 60°C for 20 minutes, dehydrated at 110°C and 2 torr, cooled to 70°C, and then deodorized by steam distillation at 234°C for 2 hours. I did it. Table 1 shows the glyceride composition before and after deodorizing treatment.

Example 2 Table 1 shows the glyceride composition before and after the deodorizing treatment in the case where only the water washing treatment of Example 1 was not performed.

Example 3 6 g of a 10% aqueous citric acid solution was added to 200 g of the diglyceride-rich fat and oil obtained by the decolorization treatment of Example 1.
After stirring for 0 minutes, add 100 g of distilled water and stir at 40°C for 10 minutes.
After stirring for a minute, the aqueous phase was removed by decantation. This water washing process was repeated 5 times, and then heated at 235°C for 2 more times.
．． Deodorization treatment was performed by steam distillation for 5 hours. Table 1 shows the glyceride composition before and after deodorizing treatment.

Comparative Example 1 A diglyceride-rich fat and oil was purified in the same manner as in Example 1, except that an aqueous citric acid solution was not added to the diglyceride-rich fat and oil obtained by the water washing treatment in Example 1. Table 1 shows the glyceride composition before and after deodorizing treatment.

Comparative Example 2 The diglyceride-rich fat and oil obtained by the decolorization treatment in Example 1 was purified by the same method as in Example 1 except that the water washing treatment and the addition of citric acid aqueous solution were not performed. Ta. Table 1 shows the glyceride composition before and after deodorizing treatment.

[0022]

[Table 1]

Example 4 An esterified product obtained by esterifying fatty acids derived from rapeseed oil with glycerin was subjected to molecular distillation to remove fatty acids and monoglycerides to obtain fats and oils rich in diglycerides. Add 15 g of 10% citric acid aqueous solution to 300 g of this diglyceride-rich fat and oil, stir at 80°C for 30 minutes, and then add 5 to
After dehydration under reduced pressure at 110°C and further cooling to 70°C, 6 g of activated clay and 1 g of activated carbon were added and the mixture was heated to 5 torr.
The mixture was decolorized at 110°C for 30 minutes, cooled to 70°C, and filtered to obtain a decolorized fat. 100 g of distilled water was added to 200 g of this decolorized oil and the mixture was stirred at 40° C. for 10 minutes, and then the aqueous phase was removed by decantation. This water washing treatment was repeated four times, and further deodorization treatment by steam distillation was performed at 235° C. for 2.5 hours. Table 2 shows the glyceride composition before and after deodorizing treatment.

Example 5 Example 4 except that citric acid in Example 4 was changed to oxalic acid.
Diglyceride-rich fats and oils were purified using the same method. Table 2 shows the glyceride composition before and after deodorizing treatment.

Example 6 A fat and oil rich in diglycerides was purified in the same manner as in Example 4 except that citric acid in Example 4 was replaced with maleic acid. Table 2 shows the glyceride composition before and after deodorizing treatment.

Example 7 Example 4 except that citric acid in Example 4 was changed to succinic acid.
Diglyceride-rich fats and oils were purified using the same method. Table 2 shows the glyceride composition before and after deodorizing treatment.

Comparative Example 3 A fat and oil rich in diglycerides was purified in the same manner as in Example 4 except that citric acid was not added. Table 2 shows the glyceride composition before and after deodorizing treatment.

[0028]

[Table 2]

[0029]

According to the purification method of the present invention, fats and oils rich in diglycerides can be purified without reducing the diglyceride content in the deodorizing step by steam distillation. Moreover, according to the purification method of the present invention, diglyceride with further improved flavor can be obtained.

Claims (16)

[Claims] 1. A method for purifying fats and oils rich in diglycerides, which comprises adding an organic acid to the fats and oils rich in diglycerides, and then deodorizing the fats and oils. 2. The method for purifying fats and oils rich in diglycerides according to claim 1, wherein the organic acid has a chelating ability. 3. The diglyceride-rich fat and oil according to claim 1 or 2, wherein the organic acid is citric acid, succinic acid, maleic acid, oxalic acid, aconitic acid, itaconic acid, citraconic acid, tartaric acid, fumaric acid or malic acid. Purification method. 4. The method for purifying diglyceride-rich fats and oils according to any one of claims 1 to 3, wherein the amount of the organic acid added is 0.1 to 2 parts by weight per 100 parts by weight of diglyceride-rich fats and oils. 5. The method for purifying fats and oils rich in diglycerides according to any one of claims 1 to 4, characterized in that after adding the organic acid, decolorization is performed using a porous adsorbent. 6. The method for purifying fats and oils rich in diglycerides according to any one of claims 1 to 4, which comprises washing with water or water containing a lower alcohol after adding the organic acid. 7. After adding the organic acid, the organic acid is decolorized using a porous adsorbent, and further washed with water or water containing a lower alcohol.
The method for refining the diglyceride-rich fats and oils described in . Claim 8: The concentration of the organic acid is 1 to 50% by weight based on water or water containing a lower alcohol.
or 7. The method for purifying fats and oils rich in diglycerides according to 7. 9. The diglyceride according to claim 6 or 7, wherein the amount of water containing an organic acid or the water containing an organic acid and a lower alcohol added is 1 to 1000 parts by weight per 100 parts by weight of diglyceride-rich fat or oil. A method for refining rich fats and oils. 10. The method for purifying fats and oils rich in diglycerides according to any one of claims 6 to 9, wherein the lower alcohol is methanol, ethanol, propanol or isopropanol. 11. The method for purifying fats and oils rich in diglycerides according to claim 1, wherein the deodorizing treatment is carried out by steam distillation. 12. The method for purifying fats and oils rich in diglycerides according to claim 11, wherein the temperature of the deodorizing treatment by steam distillation is 220° C. or higher. 13. The method for refining diglyceride-rich fats and oils according to claim 11 or 12, wherein the diglyceride-rich fats and oils are washed with water containing an organic acid or water containing an organic acid and a lower alcohol, and then deodorized by steam distillation. . 14. The method for purifying fats and oils rich in diglycerides according to claim 13, wherein the temperature of the deodorizing treatment by steam distillation is 220° C. or higher. 15. The method for refining diglyceride-rich fats and oils according to any one of claims 11 to 14, wherein the amount of steam in the steam distillation is 1 to 20 parts by weight per 100 parts by weight of diglyceride-rich fats and oils. 16. The method for refining diglyceride-rich fats and oils according to claim 15, wherein the amount of water vapor in the steam distillation is 3 to 10 parts by weight per 100 parts by weight of diglyceride-rich fats and oils.