JP6898177B2 - Oil refining method - Google Patents

Description

The present invention relates to a method for refining fats and oils.

The main purposes of refining edible fats and oils are (1) removal of impurities and (2) improvement of fats and oils flavor. It is known that the refining of fats and oils is usually carried out in the order of a degumming step, a deoxidizing step, a bleaching step and a deodorizing step on the crude oil obtained by oil extraction. Oils and fats without offensive odor can be obtained.

However, it is known that even if the fats and oils refined through the above steps are tasteless and odorless immediately after refining, a phenomenon called "modori phenomenon" occurs during storage.
This modli phenomenon is a phenomenon in which the flavor of refined fats and oils deteriorates over time, and the cause of this phenomenon has not been clarified, but aldehydes and triglycerides that tend to remain in fats and oils even after refining. It has been suggested that the effects of trace components such as the decomposition products of the above and their derivatives are suggested.
The degree of occurrence of the modli phenomenon differs depending on the oil type, and palm oil, palm oil such as palm fractionated oil and transesterified oil containing palm oil as one of the raw materials, and shea butter, shea fractionated oil, and shea butter are used. It has been known that the modli phenomenon is likely to occur in shear-based oils and fats such as transesterified oils and fats contained as one of the raw materials.
In particular, in palm oil and palm-based fats and oils, it has been confirmed that the modd phenomenon is likely to occur even when stored at room temperature or refrigerated, and countermeasures have been desired.

Regarding this modli phenomenon, for example, Patent Document 1 and Patent Document 2 disclose a method for suppressing the occurrence of the modli phenomenon by adding an acid such as phosphoric acid, citric acid, or ascorbic acid during the purification step. .. Patent Document 3 discloses a method for suppressing the occurrence of the modd phenomenon in which an adsorbent and an alkaline substance such as sodium hydroxide are brought into contact with fats and oils in the coexistence thereof.
However, these methods tend to involve denaturation of fats and oils and decomposition of triglycerides because the refined fats and oils come into contact with acids and bases. In addition, a step of removing acids and bases may be required, and the refining efficiency of fats and oils tends to decrease due to time loss and deterioration of yield.

Although it is not an object to suppress the "modori phenomenon", the applicant in Patent Document 4 includes a step of heating the fat and oil in the presence of water while pressurizing the fat and oil as a method for refining the fat and oil. Discloses the purification method of.

However, the method for purifying fats and oils disclosed in Patent Document 4 aims to reduce chlorine compounds having a relatively low molecular weight contained in edible fats and oils. In the method for refining fats and oils described in the same document, the amount of water added to 100 parts by mass of fats and oils is as large as 25 to 400 parts by mass. In addition to being required to be applied, the yield of fats and oils tends to decrease because the fats and oils tend to decrease during dehydration.

Japanese Unexamined Patent Publication No. 2006-0284666 Japanese Unexamined Patent Publication No. 2016-169391 Japanese Unexamined Patent Publication No. 2016-123331 WO2011 / 1389578

Therefore, the problem to be solved by the present application is to provide a method for refining fats and oils in which a fat and oil having a good flavor can be obtained.
Next, an object of the present invention is to provide a method for refining fats and oils, which can obtain fats and oils in which the occurrence of the modd phenomenon after refining is suppressed.
Furthermore, it is an object of the present invention to provide a method for refining fats and oils, which can obtain fats and oils having a good flavor with suppressed occurrence of the modd phenomenon, in a short time and in a high yield, while suppressing time loss and deterioration of yield. is there.

The present inventors have obtained the finding that a fat and oil having a good flavor can be obtained by passing through a step of heating and pressurizing a specific amount of water and fat and oil at a specific temperature and pressure.
In addition, it was found that the fats and oils obtained through the above steps suppress the occurrence of the modd phenomenon after refining.
Further, it has been found that the time required for the deodorizing step of fats and oils can be shortened and the fats and oils having a good flavor can be obtained by going through the above steps, so that the efficiency of the steps can be improved.
The present invention has been completed based on these findings, and is a method for refining fats and oils, which comprises a step of heating and pressurizing 100 parts by mass of fats and oils and water of 0.1 parts by mass or more and less than 25 parts by mass. when the temperature and pressure at subcritical water alone was T _S and P _S, heating and the step of pressing, refining of oils and fats under the condition where the temperature T _S becomes the total pressure in the system becomes P _S Regarding the method.

According to the method for refining fats and oils of the present invention, fats and oils having a good flavor can be obtained.
Further, according to the method for refining fats and oils of the present invention, the occurrence of the modd phenomenon after refining is suppressed, and it becomes possible to obtain fats and oils having a good flavor over time.
Further, according to the method for refining fats and oils of the present invention, fats and oils having a good flavor and in which the occurrence of the modd phenomenon is suppressed can be produced in a short time and in a high yield while suppressing time loss and deterioration of yield. Will be possible.

Hereinafter, the method for purifying fats and oils of the present invention will be described in detail based on the preferred embodiment thereof.
The method for refining fats and oils of the present invention is to heat and pressurize a specific amount of water and a specific amount of fats and oils at a specific temperature and a specific pressure.
First, the fats and oils to which the method for refining fats and oils of the present invention is applied will be described.
Examples of fats and oils to which the method for refining fats and oils of the present invention are applied include edible fats and oils. The edible fats and oils are not particularly limited, and are, for example, vegetable fats and oils such as palm oil, palm kernel oil, palm oil, corn oil, olive oil, cottonseed oil, soybean oil, rapeseed oil, rice oil, sunflower oil and safflower oil, beef tallow, and milk fat. , Lard, coconut oil, shea butter, mango kernel oil, safflower, ilippe oil, fish oil and whale oil, and one or more treatments selected from hydrogenation, fractionation and ester exchange of these oils. Examples of processed oils and fats that have been subjected to.
The method for refining fats and oils of the present invention can be applied to one kind of fats and oils selected from the above fats and oils. The method for refining fats and oils of the present invention can also be applied to mixed fats and oils in which two or more kinds selected from the above fats and oils are combined.

Next, water used in the method for refining fats and oils of the present invention will be described.
The water used in the method for refining fats and oils of the present invention is not particularly limited, and for example, tap water, mineral water, ion exchange treated water, and distilled water can be used.
In the present invention, these waters can be used alone or in combination of two or more.

In the method for purifying fats and oils of the present invention, the abundance of water is 0.1 parts by mass or more, preferably 0.5 parts by mass or more, and more preferably 1 part by mass or more with respect to 100 parts by mass of the fats and oils. And adjust so that it is less than 25 parts by mass, preferably 20 parts by mass or less, and more preferably 15 parts by mass or less. When the abundance of water with respect to 100 parts by mass of fats and oils is less than 0.1 parts by mass, the occurrence of the modd phenomenon cannot be suppressed even through the steps of pressurizing and heating the fats and oils and water, which will be described in detail below. Further, when the amount of water added to 100 parts by mass of fats and oils is 25 parts by mass or more, the fats and oils are decomposed at the same time, so that the yield is deteriorated and the refining is insufficient.
If the fat or oil contains water, adjust so that the amount of water used for the fat or oil is within the above range, including the amount of water. The water content in fats and oils is measured by a conventional method.

Next, the heating conditions and the pressurizing conditions in the method for refining fats and oils of the present invention will be described.
Method of purifying oils and fats of the present invention, the heat and pressure of the oil and the water, when the temperature and pressure at subcritical water alone was T _S and P _S, temperature T _S next to the system total pressure is performed under a condition where the P _S. The fats and oils have a low saturated vapor pressure, and when the fats and oils are heated under pressure, the fats and oils hardly vaporize. Then, when water and fats and oils are heated and pressurized in the system, the observed pressure in the system, that is, the total pressure, is substantially the same as the partial pressure of water. In the method for refining fats and oils of the present invention, heating and pressurization are performed under the condition that the temperature and total pressure in the system are such that water alone is in a subcritical state. Therefore, in the method for refining fats and oils of the present invention, it can be said that the fats and oils and water are substantially heated and pressurized at a temperature and pressure at which the water existing in the system is in a subcritical state.
Incidentally, "heat and pressure of the oil and water, when the temperature and pressure at subcritical water alone was T _S and P _S, the condition that the temperature in the system is T _S becomes a total pressure of P _S In the following, "performing in" may be simply referred to as "sub-critical water treatment", and the step of performing sub-critical water treatment may be simply referred to as "sub-critical water treatment step".

In the present invention, by passing through the sub-critical water treatment step, a refined fat or oil in which the modd phenomenon is suppressed and which has a good flavor over time can be obtained.
The reason for this is not clear, but the decomposition of aldehydes and triglycerides, which are presumed to be the cause of the modli phenomenon, while the fat and oil and water are heated while pressurizing together so that the water becomes subcritical. It is presumed that this is because the substances and their derivatives are reduced.

When fats and oils and water are heated and pressurized under conditions where the temperature and total pressure in the system reach the supercritical points (374 ° C. and 22 MPa) with water alone, the decomposition of triglycerides in the fats and oils proceeds, and fatty acids and fatty acids In addition to producing a large amount of decomposition products of fats and oils such as diacylglycerol, the dissolution of fats and oils in water reduces the yield of refined fats and oils, and suppresses the oxidation phenomenon originally contained in fats and oils. The problem arises that the components are decomposed.
Therefore, in the method for purifying fats and oils of the present invention, the heating and pressurizing of fats and oils and water are performed at high temperature and high pressure, and the temperature and total pressure in the system are below the supercritical point of water alone, that is, It is necessary to set the temperature and total pressure in the system to the conditions where water alone is in a subcritical state.
Here, the "subcritical state" in the method for refining fats and oils of the present invention means a high-temperature and high-pressure state at a temperature lower than the supercritical point of water and higher than the saturated vapor pressure of water at that temperature.

In the method for refining fats and oils of the present invention, the heating temperature and pressurizing conditions of fats and oils and water are set so that the temperature in the system is 100 ° C. or higher and lower than 374 ° C. and the total pressure in the system is 0.1 MPa or more and less than 22 MPa. can do. The heating temperature is preferably 100 to 370 ° C, more preferably 150 to 250 ° C. The pressurizing conditions are preferably 0.1 to 21 MPa, more preferably 0.3 to 21 MPa, and most preferably 1 to 17 MPa.
When the heating temperature and the pressurizing conditions are lower than the above ranges, it becomes difficult to suppress the modd phenomenon of the refined fats and oils. Further, when the heating temperature and the pressurizing conditions exceed the above ranges, the fats and oils are decomposed by the water in the supercritical state, and the yield of the refined fats and oils tends to decrease.

In the method for refining fats and oils of the present invention, passing through the sub-critical water treatment step while suppressing the decomposition of fats and oils suppresses the modri phenomenon of the fats and oils after refining, and obtains fats and oils with good flavor over time. It is preferable from the viewpoint of obtaining well-refined fats and oils.
Therefore, in the method for purifying fats and oils of the present invention, it is preferable that the fluctuation of the content of diacylglycerol in the fats and oils before and after the sub-critical water treatment step is 5% by mass or less. In the present invention, the "variation in the content of diacylglycerol" refers to the content (% by mass) of diacylglycerol in the fat and oil after the subcritical water treatment, and the diacyl in the fat and oil before the subcritical water treatment. It means the absolute value of the value obtained by subtracting the glycerol content (% by mass). In order to reduce the fluctuation of the content of diacylglycerol to 5% by mass or less, the amount of water used for fats and oils, the heating temperature and the pressurizing conditions may be appropriately adjusted. By setting the fluctuation of the content of diacylglycerol to 5% by mass or less, it is preferable from the viewpoint that fats and oils in which the modli phenomenon is suppressed can be obtained in high yield. The variation in the content of diacylglycerol in fats and oils is preferably 4% by mass or less, and more preferably 3% by mass or less.

Fluctuations in the content of diacylglycerol in fats and oils can be measured by, for example, the following method.
The fluctuation of diacylglycerol in fats and oils can be measured by, for example, the following method.
The fats and oils are analyzed by gas chromatography or reverse phase HPLC, and the contents of triglycerol, diacylglycerol and monoglycerol in the fats and oils before the subcritical water treatment are measured. Then, the ratio (% by mass) of diacylglycerol to the total amount of triglyceride, diacylglycerol and monoglycerol is calculated and used as the content (% by mass) of diacylglycerol in the fat and oil before the sub-critical water treatment. Similarly, the content (mass%) of diacylglycerol in the fat and oil after the sub-critical water treatment is measured. Then, the absolute value of the difference between the value of the content of diacylglycerol in the fat and oil before the obtained sub-critical water treatment and the value of the content of diacylglycerol in the fat and oil after the sub-critical water treatment is calculated. By obtaining it, "variation in the content of diacylglycerol" is calculated. Gas chromatography and reverse phase HPLC can be performed according to a conventional method.

Immediately before the sub-critical water treatment step is performed, the fat and oil and the water may be in a state of being separated into two phases. Further, immediately before the sub-critical water treatment step is performed, water may be dispersed in the fat or oil. From the viewpoint of increasing the interface area between the fat and oil and efficiently refining the fat and oil, it is preferable that the water is dispersed in the fat and oil.
As a method of dispersing water in fats and oils, any method such as stirring using a stirring blade or shaking or shaking can be taken.

In the method for refining fats and oils of the present invention, when sub-critical water treatment is performed with water dispersed in the fats and oils, in order to make the size of water droplets existing in the fats and oils finer, a mixture of the fats and oils and water is prepared. It is preferable to disperse water in the fat and oil by subjecting it to a homogenization treatment. By performing the homogenization treatment, even when the abundance of water with respect to 100 parts by mass of the fat and oil is small, the fat and oil can be sufficiently refined, and as a result, the time of the dehydration step is shortened. It will be easier to do.

When the homogenization treatment is performed in the oil and fat purification method of the present invention, the apparatus used for the homogenization treatment includes a kettle type cheese emulsification kettle, a high-speed shear emulsification kettle such as a Stefan mixer, a static mixer, an in-line mixer, a homogenizer, and a colloid mill. , Disper mill, high speed shear mixer and the like. The homogenization treatment can be performed, for example, at a homogenization pressure of 1 to 100 MPa. The homogenization treatment can be performed in one stage and can be performed in multiple stages.

In the method for refining fats and oils of the present invention, the sub-critical water treatment can be carried out in a closed container, and can also be carried out in a flow-type reaction vessel.

Here, a case where sub-critical water treatment of fats and oils is performed in a closed container will be described.
When subcritical water treatment of fats and oils is performed in a closed container, for example, the fats and oils and water are placed in a sealable reaction vessel equipped with a heater, sealed, heated to a predetermined temperature with a heater, and at a set temperature. , A method of holding for a predetermined time while confirming that the pressure conditions are predetermined can be mentioned.
When the sub-critical water treatment is carried out in a closed container in the method for purifying fats and oils of the present invention, the reaction time under the heating temperature and the pressurizing conditions is preferably 1 to 40 minutes, more preferably 1 to 25 minutes, and further. It is preferably 1 to 10 minutes.

Then, after the sub-critical water treatment, water is preferably removed and only fats and oils are recovered.
When subcritical water treatment of fats and oils is performed in a closed container, as a method of removing water, for example, a method of returning the inside of the container to normal pressure, cooling the water to return it to a liquid state, and then allowing it to stand for natural separation, or centrifugation. Examples thereof include a method of separating, a method of extracting fats and oils with a solvent such as hexane or diethyl ether, and a method of evaporating water by heating the system at normal pressure to negative pressure.

Next, a case where sub-critical water treatment of fats and oils is performed in a flow-type reaction vessel will be described.
When sub-critical water treatment of fats and oils is carried out in a flow-type reaction vessel, for example, sub-critical water treatment is carried out using a continuous treatment apparatus consisting of a combination of a high-pressure pump, a reaction vessel with a heater, a cooler, a back pressure valve device and the like. The method can be mentioned.
Hereinafter, this method will be described in detail.

When the above method is used, first, the fat and oil and water are transferred to a reaction vessel equipped with a heater using a high-pressure pump. At this time, it is preferable to preheat the fat and oil and water with a preheating device in advance before transferring to the reaction vessel equipped with a heater because the heating time can be shortened.
When the fat and oil and water are preheated, the fat and oil and water can be combined after preheating each. Further, the fat and oil and water can be mixed to obtain a mixture, and the obtained mixture can be preheated. In the method for refining fats and oils of the present invention, it is possible to perform preheating after mixing the fats and oils with water, especially after homogenization treatment, even if the water content of the fats and oils is small, in a flow-type reaction vessel. It is preferable because sub-critical water treatment can be performed efficiently.
The heating temperature in the preheating is preferably 60 to 350 ° C., more preferably 100 to 300 ° C., and most preferably within 30 ° C. above and below the set temperature of the reaction in the flow-type reaction vessel.

Next, the fat and oil and water are allowed to stay in the reaction vessel for a predetermined time under a set temperature and a set pressure.
When sub-critical water treatment is performed using a flow-type reaction vessel in the method for purifying fats and oils of the present invention, the reaction time under the heating temperature and the pressurizing conditions is preferably 1 to 30 minutes, more preferably 1 to 20 minutes. , More preferably 1 to 15 minutes. In the case of a continuous reaction, the residence time is generally used as the reaction time.

Then, after the sub-critical water treatment, water is preferably removed and only fats and oils are recovered.
Examples of the method for removing water in the method for refining fats and oils using a flow-type reaction vessel include a method of cooling to return the water to a liquid state and then allowing it to stand for natural separation, a method of centrifuging, hexane, diethyl ether, and the like. Examples include a method of extracting fats and oils with the solvent of No. 1 and a method of evaporating water by heating the system at normal pressure to negative pressure.
At this time, cooling and / or depressurization can be performed by a cooler or the like to a temperature and pressure at which water cannot maintain the subcritical state.
At this time, it may be in a state of normal temperature and pressure, may be depressurized while maintaining a high temperature, or may be cooled while maintaining a high pressure.
Arbitrary conditions can be set for the operation of cooling and / or depressurization in consideration of the step order of the sub-critical water treatment step in the refining step of the fat and oil and the influence on the composition of the fat and oil to be refined.
The pressure in the reaction vessel is controlled by a back pressure valve device installed before or after the cooler, preferably after the cooler.

As described above, the sub-critical water treatment of fats and oils in the present invention is possible in both a closed container and a flow-type reaction container. The method for refining fats and oils of the present invention does not require a preheating device or a back pressure valve device, and is preferably performed in a closed container because the equipment is simple. On the other hand, it is easy to insert a preheating device before the start of the reaction, it is easy to incorporate it into the conventional refining process, the total reaction time can be shortened, and the hydrolysis of fats and oils is suppressed. Subcritical water treatment of fats and oils is preferably carried out using a flow-type reaction vessel in that refined fats and oils having a low content can be obtained in a short reaction time.

Next, the step order of the sub-critical water treatment step of fats and oils in the whole method for refining fats and oils of the present invention will be described.
As described above, the conventional method for refining fats and oils comprises a degumming step, a deoxidizing step, a bleaching step, and a deodorizing step. Can be inserted into any part of the. In particular, performing the deodorizing step after the sub-critical water treatment step, particularly performing the deodorizing step after the sub-critical water treatment step, can shorten the purification step for the following two reasons. preferable.

(Reason 1) Since the flavor of fats and oils is also improved by the sub-critical water treatment step, fats and oils having good flavor can be obtained even when the step time of the deodorizing step is shortened.
Although the reason why the flavor of fats and oils is improved by the sub-critical water treatment step has not been specified, substances that are considered to affect the flavor of fats and oils by the sub-critical water treatment step, such as decomposition products of aldehydes and triglycerides, and It is presumed that the cause is that these derivatives and the like are decomposed.

(Reason 2) In the step of deodorizing fats and oils, which is usually carried out by vacuum steam distillation, heating is performed to a predetermined temperature while preliminarily reducing the pressure before blowing steam. By deodorizing the fats and oils after the sub-critical water treatment step, the water in the fats and oils after the sub-critical water treatment step is dehydrated, and the dehydration step after the sub-critical water treatment step can be omitted. Oils and fats can be refined well.

The fats and oils obtained by the refining method of the present invention can be used as edible fats and oils as edible fats and oils without any limitation as raw materials for foods and drinks, like the fats and oils obtained by the conventionally known refining methods.
Since the fats and oils obtained by the refining method of the present invention suppress the smoldering phenomenon of the fats and oils as compared with the fats and oils obtained by the conventionally known refining methods, the fats and oils and the foods and drinks containing the fats and oils It is characterized in that deterioration of flavor over time is suppressed.

Examples of the above-mentioned foods and drinks include, for example, processed foods such as margarine, shortening, fat spread, flavored fat spread, dressing, mayonnaise, chilled confectionery, oil for spraying, oil for frying, oil for chocolate, oil for batter, etc. Confectionery and bread ingredients such as flower paste and chocolate, Western confectionery, Japanese confectionery, bread, snacks, curry, stew, gratin, seasonings, instant cooked foods, processed livestock products, processed marine products, processed vegetables You can list the items.

Next, the method for improving the flavor of fats and oils of the present invention will be described.
The method for improving the flavor of fats and oils of the present invention includes a step of heating and pressurizing 100 parts by mass of fats and oils and water of 0.1 parts by mass or more and less than 25 parts by mass, and adjusts the temperature and pressure of water alone in a subcritical state. when the T _S and P _S, a heating and pressurizing the process, under the condition that the temperature of the system is T _S becomes a total pressure of P _S.
The method for improving the flavor of fats and oils of the present invention is characterized by purifying the fats and oils as described above. The type of fats and oils is not particularly limited as long as they are edible fats and oils, and the refining method is as described above.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, the present invention is not limited to the following examples.

(Manufacturing Example 1)
Bleached according to a conventional method using commercially available activated clay (Galleon Earth V2R, manufactured by Mizusawa Industrial Chemicals Co., Ltd.) with respect to physically refined RBD sheaolein oil (separated soft tissue oil of shea butter). And obtained sheaolein bleaching oil. The diacylglycerol content in the sheaolein bleaching oil was 8.4% by mass.

(Manufacturing Example 2)
The physically refined RBD palm oil was bleached according to a conventional method using commercially available activated clay (Galleon Earth V2R, manufactured by Mizusawa Industrial Chemicals Co., Ltd.) in the same manner as in Production Example 1 using 2% by mass of oil. Obtained palm bleaching oil. The content of diacylglycerol in palm bleaching oil was 6.0% by mass.

(Manufacturing Example 3)
RBD palm fractionated soft tissue oil that has undergone physical refining is subjected to random transesterification using sodium methoxide as a catalyst, and transesterified palm fractionated soft tissue oil (hereinafter, simply ester-exchanged palm fractionated soft tissue oil). May be referred to as IE-PL).
For transesterification, 0.2% by mass of sodium methoxide was added to the raw material fat and oil, and then the reaction was carried out according to a conventional method while stirring at 80 to 120 ° C. for 0.5 to 1 hour under reduced pressure.
The obtained IE-PL was bleached according to a conventional method using commercially available activated clay (Galleon Earth V2R, manufactured by Mizusawa Industrial Chemicals Co., Ltd.) in the same manner as in Production Example 1. IE-PL was obtained. The content of diacylglycerol in IE-PL bleaching oil (hereinafter, may be referred to as IE-PL bleaching oil) was 6.8% by mass.

(Manufacturing Example 4)
Physically refined RBD rapeseed oil was bleached according to a conventional method using commercially available activated clay (Galleon Earth V2R, manufactured by Mizusawa Industrial Chemicals Co., Ltd.) in the same manner as in Production Example 1. , A bleached rapeseed oil was obtained (hereinafter, may be referred to as rapeseed bleaching oil). The diacylglycerol content in the rapeseed bleaching oil was 1.2% by mass.

The following experiments were carried out using the sheaolein bleaching oil, palm bleaching oil, IE-PL bleaching oil, and rapeseed bleaching oil produced in Production Examples 1 to 4 above.
The tests of Comparative Examples 1 to 5 and Examples 1 to 8 were carried out using sheaolein bleaching oil.
The tests of Comparative Example 6 and Example 9 were carried out using palm bleaching oil.
The tests of Comparative Example 7 and Example 10 were carried out using IE-PL bleaching oil.
The tests of Comparative Example 8 and Example 11 were carried out using rapeseed bleaching oil.
Hereinafter, Examples 1 to 11 and Comparative Examples 1 to 8 and their results will be described in detail.

(Example 1)
First, the sheaolein bleaching oil obtained in Production Example 1 is heated while being pressurized with water as shown below using a flow-type reaction vessel (SUS pipe having a length of 40 cm and an inner diameter of 2.5 cm) as a reaction vessel. Was done. 10 parts by mass of water was used with respect to 100 parts by mass of sheaolein bleaching oil. Specifically, sub-critical water treatment was performed as follows.
First, the fats and oils and water were homogenized using an in-line homogenizer before being transferred to the flow-type reaction vessel, and then preheated to 170 ° C. using a preheater.
Next, the preheated oil and fat and water were transferred from the preheating device to the flow-type reaction vessel, and heating was performed while pressurizing both the oil and fat and water. At this time, the reaction temperature of the flow-type reaction vessel was 150 ° C., the pressure was 8 MPa, and the residence time in the flow-type reaction vessel was 5 minutes. The variation in diacylglycerol content after the sub-critical water treatment step of fats and oils was 0.2% by mass.

After sub-critical water treatment, the refined fats and oils are transferred from a flow-type reaction vessel to a deodorizing device and subjected to a deodorizing step by vacuum steam distillation at 230 ° C. for 80 minutes at 3% by mass of the amount of steam blown to the oil. Obtained. Regarding dehydration after the sub-critical water treatment step, when the deodorizing step was performed by heating to a predetermined temperature while preliminarily reducing the pressure, the water in the fat and oil was dehydrated. The water content of the fats and oils was measured after deodorization and found to be 200 ppm or less.

(Example 2)
The sheaolein bleaching oil obtained in Production Example 1 was heated by using the same reaction vessel as that used in Example 1 while pressurizing both fat and water.
The subcritical water treatment step was carried out in the same manner as in Example 1 except that the reaction temperature of the flow-type reaction vessel was set to 200 ° C. and the residence time in the flow-type reaction vessel was set to 3 minutes by preheating to 230 ° C. Carried out. There was no change in diacylglycerol content before and after the sub-critical water treatment step.
After that, the mixture was transferred from a flow-type reaction vessel to a deodorizing device, and subjected to a deodorizing step by reduced-pressure steam distillation at 230 ° C. for 80 minutes at 3% by mass of the amount of steam blown to obtain refined fats and oils. Regarding dehydration after the sub-critical water treatment step, the water content in the fat and oil is dehydrated when the oil and fat are heated to a predetermined temperature while preliminarily depressurizing in the deodorization step. When measured, it was 200 ppm or less.

(Example 3)
The sheaolein bleaching oil obtained in Production Example 1 was heated while being pressurized with water using the same reaction vessel as that used in Example 1.
Adjust the amount of water to 4 parts by mass with respect to 100 parts by mass of fat and oil, preheat to 230 ° C, set the reaction temperature of the flow-type reaction vessel to 200 ° C, and set the residence time in the flow-type reaction vessel to 3 minutes. The subcritical water treatment step was carried out in the same manner as in Example 1. The variation in diacylglycerol content after the sub-critical water treatment step was 0.6% by weight.
After that, the mixture was transferred from a flow-type reaction vessel to a deodorizing device, and subjected to a deodorizing step by reduced-pressure steam distillation at 230 ° C. for 80 minutes at 3% by mass of the amount of steam blown to obtain refined fats and oils. Regarding dehydration after the sub-critical water treatment step, in the deodorizing step, the water content in the fat and oil is dehydrated when the oil and fat are heated to a predetermined temperature while preliminarily depressurizing, and the water content of the fat and oil is deodorized. When measured, it was 200 ppm or less.

(Example 4)
The sheaolein bleaching oil obtained in Production Example 1 was heated while being pressurized with water using the same reaction vessel as that used in Example 1.
Adjust the amount of water to 2 parts by mass with respect to 100 parts by mass of fat and oil, preheat to 230 ° C, set the reaction temperature of the flow-type reaction vessel to 200 ° C, and set the residence time in the flow-type reaction vessel to 3 minutes. The subcritical water treatment step was carried out in the same manner as in Example 1. The variation in diacylglycerol content after the sub-critical water treatment step was 0.3% by weight.
After that, the mixture was transferred from a flow-type reaction vessel to a deodorizing device, and subjected to a deodorizing step by reduced-pressure steam distillation at 230 ° C. for 80 minutes at 3% by mass of the amount of steam blown to obtain refined fats and oils. Regarding dehydration after the sub-critical water treatment step, in the deodorizing step, the water content in the fat and oil is dehydrated when the oil and fat are heated to a predetermined temperature while preliminarily depressurizing, and the water content of the fat and oil is deodorized. When measured, it was 200 ppm or less.

(Example 5)
The sheaolein bleaching oil obtained in Production Example 1 was heated while being pressurized with water using the same reaction vessel as that used in Example 1. Adjust the amount of water to 1 part by mass with respect to 100 parts by mass of fat and oil, preheat to 230 ° C, set the reaction temperature of the flow-type reaction vessel to 200 ° C, and set the residence time in the flow-type reaction vessel for 3 minutes. The subcritical water treatment step was carried out in the same manner as in Example 1. The variation in diacylglycerol content after the sub-critical water treatment step was 0.4% by weight.
After that, the mixture was transferred from a flow-type reaction vessel to a deodorizing device, and subjected to a deodorizing step by vacuum steam distillation at 230 ° C. for 80 minutes at 3% by mass of the amount of steam blown to obtain refined oil and fat. Regarding dehydration after the sub-critical water treatment step, in the deodorizing step, the water content in the fat and oil is dehydrated when the oil and fat are heated to a predetermined temperature while preliminarily depressurizing, and the water content of the fat and oil is deodorized. When measured, it was 200 ppm or less.

(Example 6)
The sheaolein bleaching oil obtained in Production Example 1 was heated while being pressurized with water using the same reaction vessel as that used in Example 1. The amount of water is adjusted to 0.5 parts by mass with respect to 100 parts by mass of fats and oils, preheating is performed to 230 ° C., the reaction temperature of the flow-type reaction vessel is set to 200 ° C., and the water stays in the flow-type reaction vessel. The subcritical water treatment step was carried out in the same manner as in Example 1 except that the time was set to 3 minutes. The variation in diacylglycerol content after the sub-critical water treatment step was 0.5% by weight.
After that, the mixture was transferred from a flow-type reaction vessel to a deodorizing device, and subjected to a deodorizing step by reduced-pressure steam distillation at 230 ° C. for 80 minutes at 3% by mass of the amount of steam blown to obtain refined fats and oils. Regarding dehydration after the sub-critical water treatment step, the water content in the fat and oil is dehydrated when the oil and fat are heated to a predetermined temperature while preliminarily depressurizing in the deodorization step. When measured, it was 200 ppm or less.

(Example 7)
The same treatment as in Example 1 was carried out except that the fat and oil and water were not homogenized to obtain a refined fat and oil. The variation in diacylglycerol content after the sub-critical water treatment step was 0.5% by weight.

(Example 8)
In a small autoclave (pressure vessel), 500 g of the sheaolein bleaching oil obtained in Production Example 1 and water were placed so as to be 2 parts by mass with respect to 100 parts by mass of fat and oil, and the gas phase in the container was replaced with nitrogen. The container was sealed from the ground, the pressure inside the container was set to 3 MPa, and the mixture was heated from a temperature reached 150 ° C. for 20 minutes to perform subcritical water treatment. The variation in diacylglycerol content after the sub-critical water treatment step was 0.6% by weight.
After the treatment, after returning to normal pressure, the fats and oils are transferred to a four-necked flask and subjected to a deodorizing step by vacuum steam distillation at 230 ° C. for 80 minutes at 3% by mass of the amount of steam blown to obtain refined fats and oils. It was. Regarding dehydration after the sub-critical water treatment step, in the deodorizing step, the water content in the fat and oil is dehydrated when the oil and fat are heated to a predetermined temperature while preliminarily depressurizing, and the water content of the fat and oil is deodorized. When measured, it was 200 ppm or less.

(Example 9)
The palm bleaching oil obtained in Production Example 2 was subjected to a sub-critical water treatment step under the same conditions as in Example 4. The variation in diacylglycerol content after the sub-critical water treatment step was 0.3% by weight.
Then, the fats and oils were transferred from the flow-type reaction vessel to the deodorizing device, and the refined fats and oils were obtained through a deodorizing step by vacuum steam distillation at 250 ° C. for 50 minutes at 3% by mass of the amount of steam blown. Regarding dehydration after the sub-critical water treatment step, in the deodorizing step, the water content in the fat and oil is dehydrated when the oil and fat are heated to a predetermined temperature while preliminarily depressurizing, and the water content of the fat and oil is deodorized. When measured, it was 200 ppm or less.

(Example 10)
The IE-PL bleaching oil obtained in Production Example 3 was subjected to a sub-critical water treatment step under the same conditions as in Example 4. The variation in diacylglycerol content after the sub-critical water treatment step was 0.5% by weight.
After that, the fats and oils were transferred from the flow-type reaction vessel to the deodorizing apparatus, and the refined fats and oils were obtained through a deodorizing step by vacuum steam distillation at 250 ° C. for 50 minutes at a ratio of 3% by mass of the amount of steam blown to the oil. Regarding dehydration after the sub-critical water treatment step, in the deodorization step, the water content is dehydrated from the fat and oil when the fat and oil are preliminarily depressurized and heated to a predetermined temperature, and the water content of the fat and oil is measured after the deodorization. Then, it was 200 ppm or less.

(Example 11)
The rapeseed bleaching oil obtained in Production Example 4 was subjected to a sub-critical water treatment step under the same conditions as in Example 4. The variation in diacylglycerol content after the sub-critical water treatment step was 0.3% by weight.
Then, the fats and oils were transferred from the flow-type reaction vessel to the deodorizing device, and the refined fats and oils were obtained through a deodorizing step by vacuum steam distillation at 250 ° C. for 50 minutes at 3% by mass of the amount of steam blown. Regarding dehydration after the sub-critical water treatment step, in the deodorizing step, the water content in the fat and oil is dehydrated when the oil and fat are heated to a predetermined temperature while preliminarily depressurizing, and the water content of the fat and oil is deodorized. When measured, it was 200 ppm or less.

(Comparative Example 1)
1000 g of the sheaolein bleaching oil obtained in Production Example 1 was weighed in a four-necked flask, and deodorized by vacuum steam distillation at 250 ° C. for 60 minutes at 3% by mass of the amount of steam blown to the oil to purify Comparative Example 1. Oils and fats were obtained. The water content of the fats and oils was measured after deodorization and found to be 200 ppm or less.

(Comparative Example 2)
1000 g of the sheaolein bleaching oil obtained in Production Example 1 was weighed in a four-necked flask, deodorized by vacuum steam distillation at 230 ° C. for 120 minutes at 230 ° C. to 3% by mass of oil, and refined in Comparative Example 2. Oils and fats were obtained. The water content of the fats and oils was measured after deodorization and found to be 200 ppm or less.

(Comparative Example 3)
1000 g of the sheaolein bleaching oil obtained in Production Example 1 was weighed in a four-necked flask, deodorized by vacuum steam distillation at 230 ° C. for 80 minutes at 230 ° C. to 3% by mass of oil, and refined in Comparative Example 3. Oils and fats were obtained. The water content of the fats and oils was measured after deodorization and found to be 200 ppm or less.

(Comparative Example 4)
The sheaolein bleaching oil obtained in Production Example 1 was homogenized, preheated, and pressurized in a flow-type reaction vessel under the same conditions as in Example 1 only for the oil and fat without adding water. The refined oil and fat of Comparative Example 4 was obtained by heating and deodorizing.

(Comparative Example 5)
Under the same conditions as in Example 1, homogenization treatment, preheating, and pressurization in a flow-type reaction vessel were performed, except that 50 parts by mass of water was added to 100 parts by mass of the sheaolein bleaching oil obtained in Production Example 1. Was heated and deodorized to obtain refined fats and oils of Comparative Example 5. The variation in diacylglycerol content after the sub-critical water treatment step was 1.1% by weight.
Regarding dehydration after the sub-critical water treatment step in Comparative Example 5, the oil phase was recovered by separating the oil and water by centrifugation at 3000 rpm for 15 minutes before the deodorization step. The water content of the fats and oils was measured after deodorization and found to be 200 ppm or less.

(Comparative Example 6)
1000 g of palm bleaching oil obtained in Production Example 2 was weighed in a four-necked flask, deodorized by vacuum steam distillation at 250 ° C. for 50 minutes at 3% by mass of the amount of steam blown, and refined in Comparative Example 6. Oils and fats were obtained. The water content of the fats and oils was measured after deodorization and found to be 200 ppm or less.

(Comparative Example 7)
1000 g of IE-PL bleaching oil obtained in Production Example 3 was weighed in a four-necked flask, and deodorized by vacuum steam distillation at 250 ° C. for 50 minutes with 3% by mass of the amount of steam blown to the oil. 7 refined fats and oils were obtained. The water content of the fats and oils was measured after deodorization and found to be 200 ppm or less.

(Comparative Example 8)
1000 g of rapeseed bleaching oil obtained in Production Example 4 was weighed in a four-necked flask, and deodorized by vacuum steam distillation at 250 ° C. for 50 minutes with 3% by mass of the amount of steam blown to the oil. Refined fats and oils were obtained. When the water content was measured after deodorization, it was 200 ppm or less.

[Flavor evaluation]
The flavors of the fats and oils refined in Examples 1 to 11 and Comparative Examples 1 to 8 were evaluated by the following methods.
Weighed 2 g of the fats and oils refined in Examples 1 to 11 and Comparative Examples 1 to 8 in a teaspoon, put them directly in the mouth, and trained whether or not the fats and oils had an unpleasant taste according to the evaluation criteria shown below. It was evaluated by 10 specialized panelists. If the average score of 10 professional panelists is 8.0 to 8.5, it is ×, if it is 8.6 to 9.0, it is △, if it is 9.1 to 9.5, it is ○, When it was 9.6 to 10.0, it was evaluated as ⊚. The evaluation results are shown in Tables 1 and 2.
The flavor was evaluated on the day of purification, 3 days after purification, and 7 days after purification, and the change in flavor over time was evaluated.
Regarding the time course of flavor evaluation, among the refined fats and oils obtained in Examples 1 to 11 and Comparative Examples 1 to 8, the refined fats and oils using sheaolein bleaching oil and rapeseed bleaching oil were stored in a constant temperature bath at 60 ° C. The refined fats and oils using palm bleaching oil and IE-PL bleaching oil were stored in a refrigerator (measurement temperature 5 ° C.).
In addition, for the aged flavor evaluation, the fats and oils stored in the constant temperature bath at 60 ° C. are evaluated for flavors in a state where the temperature is adjusted to 60 ° C., and the fats and oils stored in the refrigerator are solidified. The flavor was evaluated while the product was in the refrigerator.
If the result of the flavor evaluation performed 3 days after the purification or 7 days after the purification is ⊚ or ○, the modli phenomenon is suppressed, and if it is Δ or ×, the modd phenomenon has occurred. Judged.

Criteria for flavor evaluation 10: No offensive taste even when contained in the mouth.
9: Put it in your mouth and wait for 2 to 3 seconds before you feel a strange taste.
8: Immediately after putting it in the mouth, it feels strange.

Comparing Example 1 and Comparative Examples 1 to 3, the refined fats and oils immediately after refining have a good flavor, regardless of the method of refining the fats and oils, even when refined by the conventional method for refining the fats and oils. there were. However, in the fats and oils refined by the refining methods of Comparative Examples 1 to 3, the modd phenomenon occurred over time regardless of the deodorizing temperature and the deodorizing time.
On the other hand, in the method for refining fats and oils of Example 1, by performing the sub-critical water treatment before the deodorizing step, the flavor is good and the occurrence of the modd phenomenon is suppressed even if the time of the deodorizing step is shortened. Refined fats and oils were obtained. From this, it was suggested that the deodorizing time can be shortened by going through the sub-critical water treatment step, so that the time required for the purification step can be shortened.
Next, comparing Example 1 and Comparative Example 4 in which the water content is different with respect to 100 parts by mass of the fat and oil, since the modd phenomenon occurs in Comparative Example 4, simply pressurizing the fat and oil. It was suggested that the hydration phenomenon of fats and oils was not suppressed only by heating, but that the water present with the fats and oils became a subcritical state, which refined the fats and oils, and as a result, the modulation phenomenon was suppressed. ..

Similarly, comparing Example 1 and Comparative Example 5 in which the water content is different with respect to 100 parts by mass of the fat and oil, when heating while pressurizing, the presence or absence of the modd phenomenon may differ depending on the water content existing with the fat and oil. Do you get it. From this, it was suggested that it is not necessary that the amount of water present together with the fat and oil is simply large, but that the water content is within a certain range to suppress the occurrence of the modd phenomenon of the refined fat and oil.
In both Example 1 and Example 2, no occurrence of the modd phenomenon was observed. This suggests that the residence time can be shortened by adjusting the preheating temperature and the reaction temperature.
Next, when Example 1 and Example 7 were compared, there was a difference in the occurrence of the modd phenomenon depending on the presence or absence of the homogenization treatment before the sub-critical water treatment. It is considered that this is because the homogenization treatment was performed and the water content was present in the fat and oil in a fine state, so that the purification was performed to a higher degree.
Next, when Example 1 and Example 8 are compared, the treatment is performed regardless of whether the sub-critical water treatment is performed in the closed container or the sub-critical water treatment in the flow-type reaction vessel. It was found that fats and oils in which the occurrence of the modd phenomenon was suppressed could be obtained regardless of the container used.
In Examples 1 to 8, no occurrence of the modd phenomenon was observed. On the other hand, there was a difference in the degree of change in flavor that occurred during long-term storage depending on the amount of water with respect to 100 parts by mass of fats and oils.

Next, in the case where different oil and fat species were subjected to sub-critical water treatment, Example 9 and Comparative Example 6 in which palm bleaching oil was subjected to sub-critical water treatment, and IE-PL bleaching oil were sub-critical. Comparing Example 10 and Comparative Example 7 which have been subjected to water treatment, and Example 11 and Comparative Example 8 which have been subjected to sub-critical water treatment of rapeseed bleached oil, the flavor immediately after refining is still any of the fats and oils. Even so, it was good. However, in Comparative Example 6, Comparative Example 7, and Comparative Example 8 which were not subjected to the sub-critical water treatment, the modli phenomenon was confirmed. On the other hand, in Examples 9, 10 and 11, it was confirmed that oils and fats having a good flavor over time were obtained in which the modd phenomenon was sufficiently suppressed. That is, even if the fats and oils were different, there was no difference in the degree of the effect of suppressing the modd phenomenon in the fats and oils subjected to the method for refining the fats and oils of the present invention. From this, it was confirmed that the method for refining fats and oils of the present invention can suppress the modli phenomenon regardless of the type of fats and oils.

Claims (6)

A method for refining fats and oils, which comprises a step of heating and pressurizing 100 parts by mass of fats and oils and water of 0.1 parts by mass or more and less than 25 parts by mass.
When the temperature and pressure at subcritical water alone was T _S and P _S, a heating and pressurizing the process, under the condition that the temperature of the system is T _S becomes a total pressure of P _S, fat Purification method. The method for purifying fats and oils according to claim 1, wherein the variation in the content of diacylglycerol in the fats and oils before and after the step of pressurizing and heating the fats and oils and water is 5% by mass or less. The method for purifying fats and oils according to any one of claims 1 and 2, wherein a homogenization treatment is performed before the step of pressurizing and heating the fats and oils and water. The method for purifying fats and oils according to any one of claims 1 to 3, wherein the above-mentioned steps of pressurizing and heating fats and oils and water are performed in a closed container. The method for purifying fats and oils according to any one of claims 1 to 3, wherein the above-mentioned step of pressurizing and heating fats and oils and water is performed in a flow-type reaction vessel. A method for improving the flavor of fats and oils, which comprises a step of heating and pressurizing 100 parts by mass of fats and oils and water of 0.1 parts by mass or more and less than 25 parts by mass.
When the temperature and pressure at subcritical water alone was T _S and P _S, a heating and pressurizing the process, under the condition that the temperature of the system is T _S becomes a total pressure of P _S, fat Flavor improvement method.