JPS5945037B2 - Method for collecting fatty acids of better quality than crude fatty acids from rice bran oil alkaline soapstock and useful rice bran pickles - Google Patents

Description

[Detailed Description of the Invention] Crude fatty acids obtained by decomposing rice bran oil alkaline soapstock with dilute sulfuric acid include, in addition to fatty acids, sterine triterpene alcohols, ferulic acid esters or sugar esters such as 4-methylsterine, and often It is known that it contains free sterine, triterpene alcohol, 4-methylsterine, etc. as a sulfonated product, and contains various substances useful as pharmaceuticals, food additives, and industrial chemicals.

Conventionally, when crude fatty acids are distilled to produce fatty acids and rice bran, the fatty acids gradually become colored.

One of the reasons for this seems to be that the sulfuric acid used to obtain the crude fatty acids from the rice bran oil soapstock is wrapped in fatty acids and is not sufficiently removed by the usual water washing method, so they are mixed together. In addition, the useful substances in the rice bran pickles also deteriorate, resulting in a decrease in the amount of harvested rice bran and poor quality. The reason for this is also thought to be that sulfuric acid is contained in the crude fatty acids and is not sufficiently removed and remains mixed therein. On the other hand, when obtaining fatty acids by distilling crude fatty acids, in order to squeeze out as much fatty acids as possible, the temperature of the distillation tank is set to 3.
The temperature is raised to nearly 00℃. As a result, good quality fatty acids cannot be obtained, and the useful substances in the rice bran are also thermally decomposed and deteriorated, resulting in very low yields and poor quality substances. In order to improve this drawback of the conventional method, the present inventor first obtained crude fatty acids by washing them with water and then using water-soluble organic solvents (monohydric lower alcohols such as methyl alcohol and ethyl alcohol, acetone, etc.). We have proposed an excellent method for producing fatty acids that generates sulfuric acid-free crude fatty acids by washing with an aqueous solution of ketones and their mixtures (
Patent Application No. 1977-097756=Special Publication No. 17520-1983
No. 2, No. 2003, a method for producing excellent fatty acids that are lighter in color than oils and fats, especially rice bran oil, and does not contain impurities without altering the effective components thereof and containing no impurities), and in particular, the distillation temperature conditions were investigated. .

The present invention is based on the results of this research, and the present inventor has improved the temperature conditions and water washing method when distilling crude fatty acids without methyl esterification, thereby producing even better quality fatty acids and useful oryzanol. It has been confirmed that a substance containing a high content of such components, particularly ferulic acid ester of cyclobranol, and a substance effective as a rancidity inhibitor and a preservative and antifungal agent can be obtained in good yield. In other words, the present inventor has confirmed the fact that useful substances in crude fatty acids are thermally decomposed when the temperature of the distillation bottom reaches about 250°C or higher, and that thermal decomposition is significantly accelerated even when a small amount of sulfuric acid is present. By collecting fatty acids at a temperature that does not exceed about 250°C, we have found that fatty acids and useful substances in rice bran do not undergo thermal decomposition or change in quality.

Furthermore, the present inventor has discovered that by washing the crude fatty acids with an aqueous solution of a water-soluble organic solvent and stopping the distillation of the fatty acids at a temperature not exceeding about 250°C, the crude fatty acids can be used as useful substances in rice bran pickles along with excellent fatty acids. Those with a high content of cyclobranol ferulic acid ester, which is said to be involved in the medicinal efficacy of oryzanol, are produced in good yields, and the substances that act as anti-rancidity agents and preservatives and antifungal agents are also of good quality. I found that it works well. Next, for the purpose of investigating the deterioration status of useful substances, three types of rice bran pitsu were used: one using the conventional method, one using the water washing method according to the present invention, and one using the water washing method according to the present invention in combination with the distillation method. Crude oryzanol was collected by extracting with a real alkali-alcohol solution and making the extract slightly acidic, and comparative tests were conducted for yield and components.

By thin layer chromatography, it was estimated that the impurities in crude oryzanol were mainly hydrocarbons. Furthermore, gas chromatography revealed that oryzanol produced by the method of the present invention contained a large amount of cyclobranol ferulic acid ester, which is said to be involved in the medicinal efficacy of oryzanol. Comparative tests were also conducted on the yield and effectiveness of substances useful as rancidity inhibitors and antiseptic and antifungal agents. A test of the ability to prevent oxidative rancidity with beef tallow, a test of the ability to prevent hydrolyzed and ketone type rancidity with hydrogenated bean oil, and a test of black mold (Asp. niger) and blue mold (P. italicu) with potato dextrose agar medium.
The antifungal ability test for m) revealed that the useful substances were not altered. Incidentally, no gradual coloring was observed in the fatty acids distilled by the method according to the present invention. On the other hand, it has been found that in order to extract oryzanol in a good yield when extracting rice bran with an alkaline-alcohol solution, it is desirable to add an alkali amount equivalent to 2 to 3 times the acid value of the rice bran.

In addition, as a method for separating the ferulic acid ester of triterpene alcohol and the ferulic acid ester of sterine from crude oryzanol, we investigated various solvents and found that by treating with acetone, the ferulic acid ester of sterine and the acetone soluble portion were separated from the acetone-insoluble portion. We confirmed by gas chromatography that ferulic acid esters of triterpene alcohols can be obtained from ferulic acid esters of triterpene alcohols, and found a method for separating ferulic acid esters of triterpene alcohols and ferulic acid esters of sterine.

Example 1 This example is intended to confirm that when rice bran pickles are collected from the crude fatty acid according to the present invention, useful substances do not deteriorate and a large yield can be obtained.

A solution of 750V of sodium hydroxide dissolved in 1.51% of water was added to 15kg of alkaline soapstock (32% moisture, 28% neutral lipids) obtained from rice bran oil (acid value 30.1) that had been previously degummed. After mixing and heating to saponify the neutral lipids therein, dilute sulfuric acid is added while stirring, and the crude fatty acids separated in the upper layer are collected.

Add 5 kg of boiling water to 51<g of this crude fatty acid, stir vigorously for 2 to 3 minutes, let stand for a while, and remove the aqueous solution in the lower layer. This operation was repeated two more times, and when the third lower layer aqueous solution was taken, it was found to have a neutral pH of around 7. In this way, crude fatty acid (1) was collected (yield: approximately 4.5 kg)
). A small amount (approximately 0.17) of this crude fatty acid (1) was taken and the presence of sulfuric acid was confirmed by the conventional barium sulfate method, and it was found to be present. 31<g of crude fatty acid (1) was taken, an aqueous solution 31 containing 30% methyl alcohol was added, and the mixture was thoroughly stirred to obtain a lower layer solution. When this lower layer solution was examined with litmus paper, it was found to be extremely acidic and sulfuric acid was found to be present. Furthermore, regarding the crude fatty acid in the upper layer, methyl alcohol 30
The lower solution treated with the aqueous solution 31 containing % of the concentration was completely neutral. In this way, crude fatty acid (2) was collected (
Yield approximately 2.9 kg). This crude fatty acid (2) is added in a small amount (approximately 0
．． 17) When the presence of sulfuric acid was confirmed using the conventional barium sulfate method, a negative result was obtained. Crude fatty acids (1)
, (2) were taken in an amount of 21<g each, and the pressure was reduced to 5 muHg.
Distillation is carried out under reduced pressure, and the temperature is raised to 300°C to almost completely collect the fatty acids in the distillate. The yield of fatty acids was about 75% in both cases, and the yield of rice bran pitsuchi, the distillation residue, was about 25%. The fatty acid obtained from the crude fatty acid (1) (a) was prepared using rice bran as a prisoner, and the crude fatty acid (2
) fatty acid obtained from (b), rice bran pickle (8)
shall be. Next, take 21<9 of the crude fatty acid (2) and reduce the pressure to 5 m.
Distilled under reduced pressure at mHg, maximum bottom temperature 250℃
Then, fatty acids and rice bran are collected. The yield of fatty acids was about 72%, and the yield of rice bran was about 28%. The fatty acids obtained in this way are referred to as (6) and rice bran (0).When the changes in color of the fatty acids were investigated over time, fatty acids (a) had an X-red color from the beginning and gradually turned red. It became more vague.

Fatty acid (b) was initially colorless, but became yellowish over time. Fatty acid (c) was initially colorless and no change in color was observed over time. Next, rice nukapituchi (4)
, (B), (100 tons each were taken and crude oryzanol was collected using 500 WLI of 1% potassium hydroxide methanol solution according to the conventional method. Furthermore, the pH of the residual liquid after collecting the crude oryzanol was lowered. (pH5 or outside is appropriate),
A viscous reddish-brown substance useful as an anti-rancid agent and a preservative and anti-fungal agent is collected.
(According to the method of concentrating substances that have anti-rancidity and anti-septic and anti-mold effects from No. 01 rice bran oil). The yield of crude oryzanol and the ingredients found from gas chromatography and ultraviolet absorption spectrum are as listed in Table 1. From the description in Table 1, when oryzanol is produced by the method of the present invention,
It can be seen that oryzanol with a high content of cyclobranol ferulic acid ester without a small amount of impurities can be obtained in good yield.

The impurities were estimated to be hydrocarbons based on thin layer chromatography.

Next, we will examine the yield of useful substances as anti-rancidity agents and antiseptic and anti-mold agents, the test results for the ability of beef tallow to prevent rancidity, the results of tests for the ability to prevent hydrolyzed and ketone-type rancidity of hydrogenated bean oil, and the results of tests for the ability of hydrogenated bean oil to prevent rancidity, as well as the results of tests on the ability to prevent rancidity in potato dextrose agar medium. Black mold (Asp. niger), blue mold (P. italicu)
Table 2 shows the test results for the minimum effective inhibitory concentration (M.I.C. To test the ability of beef tallow to prevent oxidative rancidity, take 5W9 of the viscous reddish-brown substance mentioned above, dissolve it in 10f of beef tallow (0.05% to beef tallow), place it in a glass Petri dish (9Cφ), and keep it at a constant temperature of 60°C. The peroxide value (P.O.v) was measured after 100 hours.

In the control (no additives), an increase in p shear of 42 W/Kg was observed, and in the case of rice bran, (B) and (0) with the addition of extracted substances, it was 9.7 W/Kg and 6.5 T1, respectively.
! 9/Kg, 6.0W! An increase in POv of 9/Kg was observed. As a result of the above tests, it was found that the ability to prevent oxidative rancidity is enhanced by using the method according to the present invention. Next, for the test of hydrolysis type and ketone type rancidity prevention ability, take 25Tf19 of the above viscous reddish brown substance and dissolve it in hydrogenated bean oil 507 (0.05% based on hydrogenated bean oil).
). This was placed in a glass jar (9?φ), placed in a container filled with water at the bottom, and stored in a refrigerator (5 to 7°C), and the acid value (A.V) was measured after one month. Control (no additives): 0.35A. V rises, rice nukapitsuchi prisoner, (B
) and (0), the AV increased by 0.25, 0.23, and 0.18 AV, respectively. In addition, tests for antiseptic and antifungal ability were carried out by planting black mold and blue mold on potato dextrose agar medium, and
Each of the above viscous reddish-brown substances is 20%
, 1.0.0.5 and 0.1% to determine the minimum effective inhibitory concentration (M.I.C). Rice bran (4)
) was not effective against black mold even at 2%. It also showed effectiveness against blue mold at 1%.
The extract of rice bran (B) has a 2.
The effectiveness was shown in %, and the effectiveness was shown in 1% against blue mold. Next, the extract from Rice Nucapituchi (C) showed effectiveness at 0.75% for both black mold and blue mold. From these test results, it was confirmed that the use of the method according to the present invention enhances the antiseptic and antifungal ability. Example 2 This example is intended to confirm that the yield increases or decreases depending on the alkali concentration when crude oryzanol is collected from rice bran.

Six pieces of Rice Bran RokuQ (acid value 28.0, saponification value 106) 1007 in Example 1 were prepared, and the weight of the rice bran was 1.5, 2.0, 3.0, and 4. 0
, dissolve sodium hydroxide equivalent to 7.5% and 15.0% in ethyl alcohol equivalent to 5 times the amount of rice bran pickles,
The precipitate obtained by extraction according to a conventional method and making the extract slightly acidic was tested.

In a 1.5% sodium hydroxide solution corresponding to the same molar value as the acid value, the liquid became neutral and almost no extractables were observed. In addition, in a 15.0% sodium hydroxide solution equivalent to twice the mole of the saponification value, only a small amount of precipitate was observed even when the solution was made slightly acidic. When a 2.0% sodium hydroxide solution was made slightly acidic, the yield of precipitate was 67.

In the case of 3.014.0 and 7.5% sodium hydroxide solution, there was almost no change, and the yield was 8 to 97.

1% The ElcTn value of the above precipitate at 315 nm is 2.
0, 3.01 For a 4.0% sodium hydroxide solution, approximately 2
30 and 19 in 7.5% sodium hydroxide solution.
It was 0.

Next, the precipitates in 3.0% and 7.5% sodium hydroxide solutions were measured by liquid chromatography and thin layer chromatography. It was confirmed that the precipitate contained a large amount of contaminant substances that were thought to be hydrocarbons. From the above results, the E value at 315 nm, which is unique to Oly 1% Zanol, is high, and
It was found that c7n also has a good yield and that crude oryzanol can be extracted by extraction with an alkaline solution containing 3 to 4% sodium hydroxide, that is, 2 to 3 times the acid value of rice bran.

Example 3 This example relates to a method of treating crude oryzanol with acetone to separate it into ferulic acid ester of sterine and ferulic acid ester of triterpene alcohol.

Crude fatty acid (2) was collected in the same manner as in Example 1, and
Distilled under reduced pressure at m71LHg, maximum bottom temperature 21
Fatty acids and rice bran were obtained at 0°C.

Next, this rice bran pickle (acid value 24 saponification value 100) 1k
g, and dissolve sodium hydroxide equivalent to 3% of the weight of rice bran in 5 times the amount of rice bran in methyl alcohol, extract by the usual method, and make the extract slightly acidic. Collect crude oryzanol. The yield was 3-4%. Next, acetone was added to this crude oryzanol, and the mixture was thoroughly stirred and separated into an acetone-insoluble portion and an acetone-soluble portion. The soluble and insoluble parts and crude oryzanol were saponified in a conventional manner, and the neutral fraction was subjected to gas chromatography. The results are shown in FIGS. 1, 2, and 3. From these figures, it was found that by treating crude oryzanol with acetone, it can be separated into ferulic acid ester of sterine and ferulic acid ester of triterpene alcohol.

[Brief explanation of the drawing]

Figure 1 is a gas chromatograph diagram of crude oryzanol, Figure 2 is a gas chromatograph diagram of the acetone-soluble part, and Figure 3 is a gas chromatograph diagram of the acetone-insoluble part. It is 1×102. In the figure, relative retention time (RRT = cholesterol 1.0
1.33 and 1.71 are the peaks of sterine, and 1.93, 2.21, 2.54
is the peak of triterpene alcohol.

Claims (1)

[Scope of Claims] 1 Crude fatty acids obtained by decomposing rice bran oil alkaline soapstock with sulfuric acid are washed with water, or without washing with water, are washed with an aqueous solution of a water-soluble organic solvent until neutral, and then dehydrated. , about 250
A method for collecting fatty acids and rice bran, which is characterized by performing vacuum distillation at a temperature not exceeding ℃. 2 The crude fatty acid obtained by decomposing rice bran oil alkaline soapstock with sulfuric acid is washed with water, or without washing with water, is washed with an aqueous solution of a water-soluble organic solvent until it becomes neutral, and then dehydrated.
By distilling rice bran under reduced pressure at a temperature not exceeding ℃, extracting with an alkali-alcohol solution having an alkali equivalent of 2 to 3 times the acid value of rice bran, and making the extract slightly acidic. A method for collecting crude oryzanol, which comprises collecting crude oryzanol. 3. The crude fatty acid obtained by decomposing rice bran oil alkaline soapstock with sulfuric acid is washed with water, or without washing with water, it is washed with an aqueous solution of a water-soluble organic solvent until it becomes neutral, and then dehydrated and heated at approximately 250°C.
By carrying out vacuum distillation at a temperature not exceeding A method for preparing ferulic acid esters of sterine and triterpene alcohols, characterized in that the obtained crude oryzanol is treated with acetone to collect ferulic acid esters of sterine from the acetone-insoluble part and ferulic acid esters of triterpene alcohols from the acetone-soluble parts. Preparative method for ferulic acid ester.