JPH0466231B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a method for processing natural fats and oils that can efficiently recover carotene contained in minute amounts from natural fats and oils.

Prior Art and its Problems Carotene, which is a carotenoid hydrocarbon, is known to be useful in a wide range of applications as a food coloring agent and as a substance having provitamin A action. Carotene can be obtained by synthesis, but it can also be obtained by recovering carotene contained in trace amounts in natural oils and fats. After saponification, carotene is extracted as an unsaponifiable substance with a solvent, or fatty acid lower alkyl esters are produced by adding lower alcohol to natural fats and oils containing carotene and performing alcoholysis, which is then distilled under reduced pressure. A method has been adopted in which carotene is concentrated in the distillation residue.

However, the former solvent extraction method has poor carotene recovery efficiency and requires the use of a large amount of solvent to recover carotene in a high yield, resulting in high costs and the fact that all the fats and oils after carotene recovery are There is a problem that it becomes colored soap and therefore it is difficult to use it effectively. In addition, the latter method using vacuum distillation requires distillation to be carried out at low temperatures and under high vacuum while preventing decomposition of carotene, which increases both equipment costs and operating costs, which also raises the problem of high costs.

Features of the Invention In view of the above circumstances, the present inventors have been conducting intensive research on how to efficiently recover carotene from natural oils and fats to the maximum extent possible and at a high concentration.
Natural fats and oils containing carotene are subjected to alcoholysis with a lower monoalcohol, the resulting oil phase containing carotene and containing fatty acid lower alkyl ester as a main component is collected, and a hydrophilic solvent and water are mixed with this oil phase. It has been found that the above object can be achieved by precipitating carotene and collecting it.

That is, the present inventors found that when a hydrophilic solvent and water were added to an oil phase containing carotene and mainly composed of fatty acid lower alkyl esters obtained by alcoholyzing carotene-containing natural fats and oils with lower monoalcohols, , the solubility of carotene and fatty acid lower alkyl ester, which are hydrophobic substances dissolved in a hydrophilic solvent, decreases and carotene, which is more hydrophobic, precipitates and separates, so that the solution contains carotene and a small amount of fatty acid lower alkyl ester. It is separated into a carotene concentrated layer in which esters are precipitated and a hydrophilic solvent layer containing most fatty acid lower alkyl esters, a hydrophilic solvent, and water. It is possible to obtain a concentrate containing
After collecting the carotene concentrated layer at 30 to 70°C, the temperature of the remaining hydrophilic solvent layer is set to 10 to 30°C to separate the fatty acid lower alkyl ester, which is then collected. The inventors have discovered that fatty acid lower alkyl esters and the hydrophilic solvent used can be successfully recovered, leading to the present invention.

Therefore, the present invention can recover carotene from natural oils and fats that contain a small amount of carotene in a high yield using simple equipment and operations, and can obtain a concentrate containing carotene at a high concentration. An object of the present invention is to provide a method for processing natural fats and oils that can also obtain fatty acid lower alkyl esters.

The present invention will be explained in more detail below.

Structure of the Invention In the present invention, first, natural fats and oils containing carotene are alcoholized with a lower monoalcohol, and the resulting oil phase containing carotene and having fatty acid lower alkyl ester as a main component is collected. That is, by adding lower monoalcohols such as methanol and ethanol to carotene-containing natural oils and fats, the glycerides in the natural oils and fats are alcoholyzed and converted into glycerin and lower alkyl esters of higher fatty acids, and the carotene in the oils and fats remains unreacted. It is contained in the alkyl ester phase (oil phase) together with glyceride, but in the present invention, this oil phase is collected by separating it from glycerin by an appropriate means such as static separation or centrifugation. In this case, any natural oil or fat containing carotene can be used, and for example, palm oil or the like can be suitably used.

In the present invention, a hydrophilic solvent and water are mixed with an oil phase containing separated and collected carotene and mainly composed of fatty acid lower alkyl ester to precipitate and separate carotene, and this carotene concentrated layer is left to stand and separated. A carotene-containing concentrate is obtained by collecting by appropriate means such as centrifugation or membrane separation.

Here, there are no restrictions on the method or order of mixing the hydrophilic solvent and water with the oil phase, but it is possible to dissolve the oil phase in the hydrophilic solvent and then add water to this solution to precipitate and separate carotene. Preferable in terms of workability, etc.

The type of hydrophilic solvent is not particularly limited, but specifically one or two selected from methanol, ethanol, isopropanol, and acetone.
A mixed solvent of more than one type can be suitably used. In addition, fatty acid lower alkyl ester is a hydrophilic solvent with 5 to 20
% concentration. Here, carotene is precipitated in the lower layer when methanol or ethanol is used as a hydrophilic solvent, and is precipitated in the upper layer when isopropanol or acetone is used.

Further, the amount of water added is preferably about 1 to 20% of the hydrophilic solvent. Also, the operating temperature is 10-70
℃ is suitable. In addition, since a hydrophilic solvent remains in the carotene concentrated separation layer together with carotene and some fatty acid lower alkyl esters, it is preferable to distill off this solvent by a conventional method. A concentrate can be obtained.

In the present invention, fatty acid lower alkyl esters from which carotene has been successfully removed are present in the hydrophilic solvent layer after collecting the carotene concentrated layer, and the hydrophilic solvent can be removed from the hydrophilic solvent layer by a conventional method. The decolorized fatty acid lower alkyl ester can be recovered, and by subjecting it to simple purification treatment if necessary, high quality higher fatty acids and surfactant raw materials can be obtained.

In this case, after collecting the carotene concentrated layer, when collecting the fatty acid lower alkyl ester from the hydrophilic solvent layer, the hydrophilic solvent and water are mixed into the oil phase containing carotene and mainly composed of the fatty acid lower alkyl ester. After the carotene is precipitated at 30 to 70°C and the carotene concentrated layer is collected, the remaining hydrophilic solvent layer is replenished with a hydrophilic solvent as necessary and the temperature is adjusted to 10 to 30°C. By doing this, the decarotened fatty acid lower alkyl ester can be efficiently precipitated, and by collecting this, the fatty acid lower alkyl ester, the hydrophilic solvent, and water can be recovered. In this case, it is better to have a larger temperature difference between the first step of collecting the carotene concentrated layer and the second step of collecting the fatty acid lower alkyl ester, but it is practically preferable to provide a temperature difference of 20 to 40°C. The hydrophilic solvent and water recovered by this method contain some fatty acid lower alkyl esters and carotene, but can be used repeatedly as a carotene separation solvent.

In addition, the carotene concentrated layer collected by the above-mentioned method may be brought into contact with a styrene-divinylbenzene copolymer resin either as it is or after dehydration and solvent removal, thereby adding carotene and remaining ester to the styrene-divinylbenzene copolymer resin. After adsorption, the styrene-divinylbenzene copolymer resin is brought into contact with alcohol to elute and separate the ester component into the alcohol, and then the styrene-divinylbenzene copolymer resin is treated with a hydrophobic solvent that is easily soluble in carotene. The carotene can be eluted and separated in this hydrophobic solvent by contacting with the hydrophobic solvent, thereby making it possible to further concentrate the carotene in the carotene-concentrated layer to a higher concentration.

In this case, there are no restrictions on the shape of the styrene-divinylbenzene copolymer resin, but powder-like ones are preferably used.

In addition, there is no limit to the method of bringing the carotene concentrated layer into contact with the styrene-divinylbenzene copolymer resin, and any suitable method such as a column method or batch method can be adopted, but the column method is the most efficient method for removing carotene. It is preferable because it can be adsorbed. In this case, the loading amount of the carotene concentrated layer relative to the resin capacity packed in the column is preferably 0.2 to 0.5 g/ml-resin, and if it exceeds 0.5 g/ml-resin, the resin will reach a saturated adsorption state. carotene may flow out from the column.

In addition, when bringing the carotene concentrated layer into contact with the styrene-divinylbenzene copolymer resin, it is preferable to dilute the carotene concentrated layer with alcohol used for elution of the ester component, which will be described later.This makes contact with the resin more efficient. can be made to do so.

Styrene-divinylbenzene copolymer resin has the property that the more hydrophobic it is, the more easily it is adsorbed, so it is preferentially adsorbed in the order of carotene>ester>alcohol.

Furthermore, after adsorbing the carotene concentrated layer on the styrene-divinylbenzene copolymer resin, a non-carotene-eluting alcohol, preferably a lower monoalcohol having 1 to 4 carbon atoms, is brought into contact with the alcohol to absorb the carotene concentrated layer. Only alcohol-soluble ester components are eluted and separated. Here, it is particularly preferable to use methanol or ethanol as the elution solvent.

Note that these elution solvents may be used alone or as a mixed solvent of two or more.
Further, it is preferable that the oil elution operation be performed using alcohol in an amount of 1 to 5 times the volume of the resin.

After that, the styrene after separating the ester component
A hydrophobic solvent in which carotene is easily soluble is brought into contact with the divinylbenzene copolymer resin, and carotene is eluted and separated into the hydrophobic solvent, and then collected.

In this case, there is no restriction on the type of hydrophobic solvent in which carotene is readily soluble, but one or a mixed solvent of two or more of hexane, chloroform, petroleum ether, etc. is preferably used. However, when the recovered carotene is used for foods such as food coloring, it is particularly preferable to use hexane as the elution solvent from the viewpoint of safety.

In addition, the carotene elution operation is carried out from 0.5 to 0.5 of the resin volume.
It is preferable to use twice the amount of hydrocarbon, so that the carotene adsorbed on the resin can be almost completely eluted.

In addition, when the above method is carried out using a column method, the column temperature at the stage of adsorption of the carotene concentrated layer and elution of oily substance with alcohol is 0 to 0.
The temperature is preferably about 80°C, especially about 0 to 20°C,
This increases carotene adsorption and improves the concentration ratio. Further, the column temperature in the carotene elution step using the hydrophobic solvent can be set to any temperature below the boiling point of the hydrophobic solvent. Here, the resin in the column from which carotene has been removed can be used repeatedly by replacing the adhering hydrophobic solvent with alcohol for ester elution.

Depending on the use, the carotene separated from the resin and collected by the above method may be used as a solvent (hydrophobic solvent).
It can be used as is without distilling it off, but
Preferably, the solvent is distilled off before use. Here, the solvent can be distilled off by a conventional method.

Effects of the Invention As explained above, the method for treating natural oils and fats according to the present invention alcoholizes natural oils and fats containing carotene with a lower monoalcohol, and contains the produced carotene and fatty acid lower alkyl ester as the main component. At the same time, the oil phase containing carotene and containing fatty acid lower alkyl ester as a main component was mixed with a hydrophilic solvent and water to precipitate carotene, and this was collected. Carotene in natural fats and oils, which has conventionally been mostly decomposed in the natural fats and oils refining process and has not been effectively utilized, can be reliably concentrated and recovered at a high concentration with a simple operation. Moreover, since the method of the present invention does not require a high-temperature treatment step, carotene in natural fats and oils can be recovered in high yield without loss due to decomposition, and fatty acid lower alkyl ester from which carotene has been removed can be recovered as a by-product. .

In addition, a hydrophilic solvent and water are mixed with an oil phase containing carotene and fatty acid lower alkyl ester as a main component at 30 to 70°C to collect a carotene concentrated layer, and the remaining hydrophilic solvent layer is 30℃
By cooling the fatty acid lower alkyl ester to a temperature of When this method is adopted, the solvent can be recovered with a small amount of heat for cooling compared to the case where the hydrophilic solvent is recovered by distilling the hydrophilic solvent layer, and the recovered solvent is also mixed with carotene concentrate and lower fatty acids. Replenish the solvent and water that came out of the system with the alkyl ester (approximately 1/10 amount of oil phase)
Because it can be used repeatedly as a carotene separation solvent, it is very economical in terms of energy.

EXAMPLES The present invention will be specifically explained below with reference to Examples.

Example 1 30g crude palm oil containing 620ppm carotene
10 g of methanol and 0.24 g of caustic soda are added to carry out a methyl esterification reaction, and the resulting ester layer is collected, washed with 5 g of water, and then dehydrated by a conventional method. Next, after the ester layer was uniformly dissolved in 210 g of methanol, 8.5 g of water was added thereto, and the mixture was allowed to stand at 20° C. for 1 hour. Thereafter, the lower layer in which carotene was precipitated was separated and collected, and remaining trace amounts of methanol and water were removed to obtain 5.8 g of a carotene-containing concentrate containing 2720 ppm of carotene (carotene concentration ratio: 4.4 times, carotene recovery rate: 84.8
%).

Furthermore, methanol and water were removed from the upper layer after the lower layer was separated and collected to obtain 23.3 g of decolorized ester with a low carotene concentration of 97 ppm.

Furthermore, after mixing 40 g of methanol and 1.5 g of water with 5.8 g of the above carotene-containing concentrate containing 2720 ppm carotene, the mixture was allowed to stand, and the remaining methanol and water were removed from the generated lower layer to obtain carotene containing 1.1% carotene. 1.2 g of containing concentrate was obtained.

Example 2 30g crude palm oil containing 583ppm carotene
was treated at the same time as in Example 1, and the resulting ester layer was uniformly dissolved in 450 g of methanol, and then 45 g of water was added thereto and allowed to stand at 60° C. for 1 hour. After that, the lower layer in which carotene has precipitated is separated and collected, and residual trace amounts of methanol and water are removed.
Carotene-containing concentrate containing 2500ppm carotene
5.5 g was obtained (carotene concentration ratio: 4.3 times, carotene recovery rate: 78.6%).

In addition, when the upper layer was cooled to 20℃ and left to stand after separating and collecting the lower layer, the carotene concentration increased.
7 g of decolorized ester was precipitated at a low concentration of 150 ppm. By collecting this, methanol
447g, water 44g and fatty acid lower alkyl ester
A solvent layer containing 14.7 g (carotene concentration 63 ppm) could also be recovered.

Example 3 30g crude palm oil containing 518ppm carotene
was treated in the same manner as in Example 1, and the obtained ester layer was uniformly dissolved in 200 g of ethanol, and then 54 g of water was added thereto and allowed to stand at 20° C. for 1 hour. After that, the lower layer in which carotene was precipitated was separated and collected, and the remaining traces of ethanol and water were removed.
A carotene-containing concentrate containing 1400 ppm carotene was obtained (carotene concentration magnification 2.7 times, carotene recovery rate
72.1%).

Further, after separating and collecting the lower layer, ethanol and water were removed from the upper layer to obtain 21.0 g of color-enhancing ester with a low carotene concentration of 175 ppm.

Example 4 30g crude palm oil containing 530ppm carotene
was treated in the same manner as in Example 1, and the resulting ester layer was uniformly dissolved in 200 g of isopropanol.
Add 147 g of water to this and let stand at 20°C for 1 hour. Thereafter, the upper layer in which carotene was precipitated was separated and collected, and residual trace amounts of isopropanol and water were removed to obtain 16.8 g of a carotene-containing concentrate containing 866 ppm of carotene (carotene concentration ratio: 1.6 times,
Carotene recovery rate 90.9%).

Example 5 30g crude palm oil containing 600ppm carotene
was treated in the same manner as in Example 1, and the resulting ester layer was uniformly dissolved in 200 g of acetone.
Add 45g of water and let stand at 20°C for 1 hour. After that, the upper layer in which carotene was precipitated was separated and collected, and the remaining traces of acetone and water were removed.
Carotene-containing concentrate containing 990ppm carotene
14.8 g was obtained (carotene concentration ratio: 1.7 times, carotene recovery rate: 81.4%).

Example 6 30g crude palm oil containing 670ppm carotene
was treated in the same manner as in Example 1, and 220 g of a 4% methanol solution was added to the obtained ester layer, thoroughly mixed, and then centrifuged at 20°C. The obtained lower layer is collected, dehydrated, and then passed through a column packed with 20 ml of styrene-divinylbenzene copolymer resin powder at 20°C to be adsorbed. After passing the liquid, add 100ml of methanol to the column at SV = 3.5.
(Hr ^-1 ) to elute and separate the ester component.
Next, hexane is passed through the column to elute and separate carotene, and hexane is distilled off from this hexane solution to obtain a carotene concentrate containing 13.2% carotene.
0.12 g was obtained (carotene concentration ratio: 197 times, carotene recovery rate: 78.8%).

Next, a reference example is shown.

Reference example: 30g of crude palm oil containing 620ppm carotene
10 g of methanol and 0.24 g of caustic soda are added to carry out a methyl esterification reaction, and the resulting ester layer is collected, washed with 5 g of water, and then dissolved in 100 ml of methanol. This ester methanol solution is passed through a column filled with 100 ml of styrene-divinylbenzene copolymer resin powder at a column temperature of 20° C., and carotene, methyl ester of palm oil, and terminally reacted palm oil are adsorbed onto the resin. After passing the liquid, add 200ml of methanol to the column.
is passed through the solution at SV=2 (Hr ^-1 ) to elute and separate the ester and unreacted palm oil. Next, 100 ml of n-hexane is passed through the column to elute and separate carotene. Hexane is distilled off from this hexane solution to obtain 0.35g of carotene concentrate containing 3.9% carotene.
(Carotene concentration magnification 63 times, carotene recovery rate
73%).

In addition, in the above-described method, the carotene concentration ratio was investigated when the temperature inside the column was variously changed in the adsorption and elution steps. The results are shown in the drawing.

[Brief explanation of drawings]

The figure is a graph showing the relationship between column internal temperature and carotene concentration ratio when the column internal temperature was variously changed in the adsorption and elution steps in a reference example.

Claims (1)

[Scope of Claims] 1. Alcoholyze natural oils and fats containing carotene with lower monoalcohols, collect the resulting oil phase containing carotene and mainly consisting of fatty acid lower alkyl esters, and make this oil phase hydrophilic. 1. A method for treating natural fats and oils, characterized in that carotene is precipitated by mixing a solvent and water, and the precipitated carotene is collected. 2. The treatment method according to claim 1, wherein the hydrophilic solvent is one or a mixed solvent of two or more selected from methanol, ethanol, isopropanol, and acetone. 3. The treatment method according to claim 1 or 2, wherein a hydrophilic solvent and water are mixed into an oil phase containing carotene and containing fatty acid lower alkyl ester as a main component at 10 to 70°C. 4. Mix a hydrophilic solvent and water to an oil phase containing carotene and mainly consisting of fatty acid lower alkyl ester to precipitate carotene, collect the precipitated carotene, and then remove the fatty acid in the remaining hydrophilic solvent layer. The treatment method according to any one of claims 1 to 3, wherein the fatty acid lower alkyl ester is collected by separating and removing a hydrophilic solvent and water from the lower alkyl ester. 5. Precipitating carotene by mixing a hydrophilic solvent and water with an oil phase containing carotene and mainly containing fatty acid lower alkyl ester at 30 to 70°C,
After collecting this precipitated carotene, the remaining hydrophilic solvent layer is adjusted to 10 to 30°C to separate and precipitate the fatty acid lower alkyl ester from the hydrophilic solvent and water, and the ester is collected. A processing method according to claim 4.