JPWO2006064643A1 - Oil and fat manufacturing method - Google Patents

Abstract

Alcohol is added to the raw oil and fat, and this is brought into contact with the acidic gel-type cation exchange resin to esterify the free fatty acid in the raw oil and fat. Thereby, compared with the method using the conventional acid type solid cation exchange resin, the esterification efficiency of a free fatty acid can be improved. Moreover, when the raw material fats and oils contain a metal ion, it can be removed by the acidic gel cation exchange resin. And in the manufacturing method of this invention, even if useful ingredients, such as a carotene and a tocotrienol, are contained in the said raw material fats and oils, these alteration and loss | disappearance can be prevented.

Description

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

  Oils and fats such as palm oil contain free fatty acids due to hydrolysis of triglycerides by lipase. Conventionally, as a method for reducing the content of free fatty acids in fats and oils, techniques such as neutralization with an aqueous alkaline solution, removal with an adsorbent, and pre-esterification with an acid catalyst have been used.

  For example, an alkali deoxidation method for free fatty acids in fats and oils by the Zenith method (see Patent Document 1) and a method for adsorbing and removing free fatty acids using hydroxyapatite (see Patent Document 2) have been proposed. However, these methods have a problem that the fats and oils themselves are largely lost and the scale of industrial facilities and the like is increased.

  Moreover, the preesterification method of the free fatty acid in fats and oils which uses at least one of an aliphatic and aromatic sulfonic acid as a catalyst is proposed (refer patent document 3). However, this method has a problem that metal ions contained in fats and oils cannot be removed. In addition to this problem, when this method contains useful components such as carotene and tocotrienol in fats and oils, there is a problem that they are decomposed (disappeared) and altered.

And in order to solve these problems, the method using an acid type solid cation exchange resin is proposed (refer patent document 4). This method is a method of reducing the content of free fatty acids in fats and oils by treating the fats and oils with a lower monohydric alcohol in the presence of an acidic esterification catalyst, and using an acid-type solid cation exchange resin as the catalyst To do. According to this method, the content of free fatty acids can be reduced and metal ions can be removed, loss of useful components such as carotene is small, and the implementation scale does not increase more than necessary. However, even with this method, the esterification efficiency of free fatty acids is not sufficient.
JP-A-4-370195 JP-A-63-97696 Japanese Patent Laid-Open No. 61-140544 JP-A 61-168696

  Then, this invention aims at provision of the manufacturing method of fats and oils which can further improve the esterification efficiency of the free fatty acid in fats and oils.

  In order to achieve the object, the production method of the present invention is a method for producing fats and oils having a step of esterifying a free fatty acid in raw material fats and oils with an alcohol, and the esterification step comprises adding alcohol to the raw material fats and oils. It is the manufacturing method of fats and oils which is the process of adding and making this contact an acidic gel type | mold cation exchange resin.

  Thus, the method for producing fats and oils of the present invention is characterized in that an acidic gel cation exchange resin is used as a catalyst used for esterification of free fatty acids in the fats and oils. Thereby, the manufacturing method of this invention can improve the esterification efficiency of a free fatty acid compared with the method using the conventional acid type solid cation exchange resin.

  The reason why the production method of the present invention can improve the esterification efficiency of free fatty acid compared with the method using a conventional acid type solid cation exchange resin is not clear, but the mechanism is presumed as follows. . That is, in the conventional method using an acid-type solid cation exchange resin, it is considered that water generated by esterification of free fatty acid adheres to or adsorbs on the exchange resin, and as a result, the catalytic ability of the exchange resin decreases. On the other hand, in the production method of the present invention, since an acidic gel cation exchange resin is used, water generated by esterification of free fatty acid is taken into the acidic gel cation exchange resin as hydrated water, and catalytic activity is increased. It is thought to prevent a decrease in Note that this mechanism is only an assumption and does not limit the present invention.

  Moreover, according to the manufacturing method of the fats and oils of this invention, for example, when the said raw material fats and oils contain a metal ion, it is possible to remove with the said acidic gel type cation exchange resin. And in the manufacturing method of this invention, when useful ingredients, such as a carotene and a tocotrienol, are contained in the said raw material fats and oils, these alteration and loss | disappearance can be prevented.

  In the production method of the present invention, the resin contained in the acidic gel cation exchange resin is preferably a styrene-based base material, and the crosslinking agent contained in the acidic gel cation exchange resin is divinylbenzene. preferable. Moreover, the crosslinking degree (content ratio of a crosslinking agent) of the acidic gel cation exchange resin is not particularly limited, but is preferably in the range of 3 to 10% by weight. That is, if it is 3% by weight or more, it is more preferable in terms of resin strength, and if it is 10% by weight or less, the esterification efficiency of free fatty acid can be further improved. In addition, the cross-linking degree of the acidic gel cation exchange resin is more preferably in the range of 3 to 9% by weight, and still more preferably in the range of 4 to 8% by weight. Above all, when the free fatty acid has the highest esterification efficiency, and the raw material fats and oils contain useful components such as carotenes and tocotrienols, these alterations and disappearances are sufficiently suppressed, and the mechanical strength of the resin is sufficient. Particularly preferred are those having a cross-linking degree of 4% by weight, which is excellent in the resistance. The “gel-type cation exchange resin” in the present invention generally means a cation exchange resin in which the inside of the particle is composed of a uniform crosslinked polymer.

  In the production method of the present invention, it is preferable that the esterification step is a step of passing the raw material fat added with the alcohol through a column filled with the acidic gel type cation exchange resin. From the viewpoint of further improving the esterification efficiency of free fatty acids in the passage of the raw oil and fat, the column temperature is, for example, in the range of 40 to 70 ° C, and preferably in the range of 50 to 65 ° C. More preferably, it is the range of 60-65 degreeC. Moreover, the said column residence time of the said raw material fats and oils is the range of 60-480 minutes, for example, Preferably, it is the range of 100-360 minutes, More preferably, it is the range of 100-240 minutes.

  In the production method of the present invention, the amount of the alcohol is appropriately determined depending on the fatty acid distribution of the raw oil and fat, etc., for example, in the range of 5 to 30 parts by weight with respect to 100 parts by weight of the raw oil and fat. Preferably, it is the range of 10-28 weight part with respect to 100 weight part of said raw material fats and oils, More preferably, it is the range of 15-26 weight part with respect to 100 weight parts of said raw material fats and oils.

  In the production method of the present invention, the amount of water in the alcohol is preferably as low as possible, for example, 1500 ppm or less, preferably 1000 ppm or less, and more preferably 600 ppm or less. The lower limit of the amount of water in the alcohol is not particularly limited, but is, for example, about the detection limit (0 ppm), preferably about 100 ppm.

  In the production method of the present invention, it is preferable to use, for example, a lower monohydric alcohol as the alcohol. As said lower monohydric alcohol, a C1-C4 thing is preferable, For example, methanol, ethanol, propanol, a butanol etc. are mentioned. These may be used alone or in combination of two or more. Among these, it is preferable to use methanol.

  In the manufacturing method of this invention, when the metal fat is further contained in the said raw material fats and oils, it is preferable to remove in the said esterification process. Examples of metal ions contained in the raw material fats and oils include copper ions, iron ions, sodium ions, potassium ions, calcium ions, and magnesium ions.

  The production method of the present invention preferably further includes an alcoholysis step in which alcohol is added to the fats and oils in which the free fatty acid is esterified by the esterification step.

  The raw oil and fat used in the production method of the present invention is not particularly limited, and examples thereof include beef tallow, coconut oil, palm oil, palm kernel oil, rapeseed oil, soybean oil, sunflower oil, corn oil and the like. These may be used alone or in combination of two or more. Moreover, it is preferable to use what contains useful components, such as a carotene, a tocopherol, and a tocotrienol, as the said raw material fats and oils. Among them, it is particularly preferable to use palm oil containing a large amount of carotene and tocotrienol. In addition, in this invention, the fats and oils before using for an esterification process are set to "raw material fats and oils", and the fats and oils after using for an esterification process are set to "purified fats and oils".

  Next, the production method of the present invention will be described with examples.

  As described above, in the production method of the present invention, free fatty acids in the raw material fats and oils are esterified by an esterification step in which alcohol is added to the raw material fats and oils are brought into contact with an acidic gel cation exchange resin. In addition, you may perform a degumming process to the said raw material fats and oils before application of the manufacturing method of this invention. In the degumming treatment, for example, warm water is added to the raw oil and fat to hydrate phospholipids, or aggregation by inorganic acid or heat treatment is performed, and then sedimentation or centrifugation is performed to remove gum. Can be done.

  The raw material fats and oils are as described above.

  The amount of alcohol added and the amount of water in the alcohol are as described above. As described above, methanol is preferably used as the alcohol.

  Examples of the acidic gel cation exchange resin include sulfonated styrene-divinylbenzene copolymers. Examples of the commercially available acidic gel-type cation exchange resin include, for example, trade names DIAION SK104, SK106, SK 1B and SK110 manufactured by Mitsubishi Chemical Corporation, trade names Dowex, Rohm and Haas manufactured by Dow Chemical Co., Ltd. The brand name Amberlite manufactured by the company can be mentioned. The degree of crosslinking of the acidic gel cation exchange resin is as described above. In addition, it is preferable to wash | clean the said acidic gel type cation exchange resin with the alcohol for washing | cleaning as pre-processing. As the washing alcohol, it is preferable to use the same alcohol as that added to the raw material fat. The washing is preferably performed until the amount of water in the washing alcohol does not change before and after washing. Thereby, the water | moisture content in the said acidic gel type | mold cation exchange resin is substituted by the said alcohol for washing | cleaning, and can esterify a free fatty acid still more efficiently. Specifically, for example, the acidic gel cation exchange resin may be washed with 2 to 5 times the volume of the washing alcohol.

  Next, the fatty acid in the raw material fat can be esterified by adding the alcohol to the raw material fat and bringing it into contact with the acidic gel cation exchange resin. As described above, in the production method of the present invention, it is preferable that the esterification step is a step of passing the raw material fat to which the alcohol is added through a column packed with the acidic gel type cation exchange resin. In this case, the column temperature and the column residence time of the raw oil and fat are as described above.

  In the fats and oils obtained by the esterification step (hereinafter referred to as “refined fats and oils”), the deoxidation rate is not particularly limited, but is, for example, 70% or more, preferably 80% or more. More preferably, it is 90% or more. In addition, the said deoxidation rate means the ratio (weight%) of the esterified free fatty acid with respect to the total free fatty acid in raw material fats and oils, for example, can be measured by the method as described in the below-mentioned Example.

  Moreover, when the said raw material fats and oils contain a metal ion, it is preferable that the metal ion density | concentration is below a detection limit in the said refined fats and oils. In addition, the said metal ion concentration can be measured by the method as described in the below-mentioned Example, for example.

  And when the raw material fats and oils contain carotene and tocotrienol, in the refined fats and oils, both the carotene disappearance rate and the tocotrienol alteration rate are preferably 10% by weight or less, more preferably both 6 % By weight or less, more preferably 4% by weight or less. The carotene disappearance rate and the tocotrienol alteration rate can be measured, for example, by the method described in Examples described later.

  As described above, the production method of the present invention may further include an alcoholysis step in which alcohol is added to the refined fat and oil to cause alcoholysis. In addition, when performing the said alcoholysis process, a dehydration process may be needed prior to it. That is, the refined fats and oils contain water generated by esterification of free fatty acids. This amount of water depends on the amount of free fatty acids in the raw oil and fat and the esterification rate. When raw material fats and oils are not deteriorated so much, the free fatty acid concentration in raw material fats and oils is, for example, 5% by weight or less, and the amount of water generated by esterification is, for example, 5000 ppm or less. With this amount of water, a sufficient reaction rate can be achieved by increasing the amount of alkali catalyst in the later described alcoholysis step. However, if the water content increases further, it may be difficult to achieve a sufficient reaction rate. In this case, it is preferable to first perform a dehydration step of dehydrating moisture in the refined fat. As the dehydration method, for example, thin film distillation under vacuum, evaporation at 150 ° C. under atmospheric pressure and excess methanol are added to and mixed with purified oil and allowed to stand, and the upper methanol layer (this layer is moisture) For example).

  When alcohol is added to the refined fats and oils to cause alcoholysis, triglycerides in the refined fats and oils are decomposed and separated into an oil phase mainly composed of fatty acid lower alkyl ester and a phase mainly composed of glycerin. At the time of this separation, when useful components such as carotene and tocotrienol are contained in the refined fat and oil, the oil phase is shifted to. The alcohol for alcoholysis is preferably a lower alcohol such as methanol. The addition amount of the alcohol for alcoholysis is, for example, in the range of 5 to 50 parts by weight and preferably in the range of 10 to 40 parts by weight with respect to 100 parts by weight of the refined fat. The temperature of the alcoholysis is, for example, in the range of 50 to 100 ° C., preferably in the range of 60 to 80 ° C., and the reaction time of the alcoholysis is, for example, in the range of 15 to 90 minutes, preferably 40 to 70 minutes. Range. The alcoholysis is preferably performed in the presence of a catalyst. As the catalyst, an alkali catalyst is preferable, and for example, sodium hydroxide, potassium hydroxide, sodium methylate and the like can be used. The addition amount of the catalyst is, for example, in the range of 0.1 to 0.5 parts by weight, and preferably in the range of 0.2 to 0.3 parts by weight with respect to 100 parts by weight of the refined fat. If the said alcoholysis is performed with respect to the said refined fats and oils, the ester yield will improve and the alkyl ester excellent in oxidation stability can be obtained. Further, when recovering useful components such as carotene and tocotrienol, most of them are not altered or lost, so the recovery rate is improved.

  Although the use of the fats and oils manufactured by the manufacturing method of this invention is not restrict | limited at all, For example, transesterification can be performed further, for example, the obtained ester is mixed with a light oil as biodiesel fuel, for example. Can be used. Further, the ester can be further subjected to ethylene oxide addition, hydrogenation, higher alcoholation or sulfonation to synthesize a surfactant, and can be used as a cleaning agent, for example.

  Next, examples of the present invention will be described together with comparative examples. However, the present invention is not limited by the following examples and comparative examples. In addition, the measuring method of each characteristic in a following example and a comparative example is as showing below.

(1) Deoxidation rate After removing moisture and methanol contained in a sample (oil and fat, the same shall apply hereinafter) with an evaporator, each sample is pretreated by passing it through a filter paper filled with anhydrous sodium sulfate. 5-10 g (Wt1) of each sample after the pretreatment is accurately weighed and placed in a 200 mL Erlenmeyer flask. Thereto, about 50 mL of neutralized alcohol is added to dissolve the sample. After adding several drops of phenolphthalein as an indicator, titrate with 1/10 normal KOH solution. From this drop constant (mL), the acid value is calculated by the following formula (1).

Acid value (mgKOH / g) = A / B (1)
A: titration constant of 1/10 normal KOH × factor of titrant B: sample weight (Wt1)

  This measurement is performed on the refined fat and oil and the raw oil and fat, and the deoxidation rate is calculated by the following formula (2).

Deoxidation rate (%) = {(C1-C2) / C1} × 100 (2)
C1: Acid value of raw oil (mgKOH / g)
C2: Acid value of purified fat (mgKOH / g)

(2) Carotene disappearance rate The sample is pretreated in the same manner as in the deoxidation rate measurement method. 0.1 g (Wt2) of each sample after the pretreatment is accurately weighed, put in a measuring flask, made up to 50 mL with cyclohexane, and used as a sample solution. This sample solution is put into a measurement cell of a spectrophotometer, and absorbance Ab at a wavelength of 448 nm is measured. From this measured value, the carotene concentration is calculated by the following formula (3).

Carotene concentration (ppm) = D × 200 / E (3)
D: Absorbance Ab
E: Sample weight (Wt2)

  This measurement is performed for refined fats and oils and raw oils and fats, and the carotene disappearance rate is calculated by the following formula (4).

Carotene disappearance rate (%) = {(F1-F2) / F1} × 100 (4)
F1: Carotene concentration of raw material fat (ppm)
F2: Carotene concentration of refined fat (ppm)

(3) Tocotrienol alteration rate A sample is pretreated in the same manner as in the deoxidation rate measurement method. 0.5 g of each sample after the pretreatment is accurately measured, put into a measuring flask, made up to 50 mL with methanol, and used as a sample solution. On the other hand, a standard solution is prepared so that each standard tocopherol (α, β, γ, δ) has a predetermined concentration. The standard solution is subjected to HPLC analysis under the following conditions, and a calibration curve for each tocopherol is prepared in advance. Each tocotrienol sensitivity (α, β, γ, δ) was the same as each tocopherol sensitivity. Next, the sample solution is analyzed in the same manner, and each concentration is calculated from the calibration curve and summed to obtain a total tocotrienol concentration (ppm).

HPLC column condition column: manufactured by DuPont, trade name Zorbax ODS
4.6φ × 250mm, particle size 5μm
Eluent: methanol / water = 98/2 (v / v)
Flow rate: 0.65 mL / min Detector: UV 284 nm
Sample volume: 20 μL

  This measurement is performed on the refined fat and oil and the raw oil and fat, and the tocotrienol alteration rate is calculated by the following formula (5).

Tocotrienol alteration rate (%) = [(T1-T2) / T1] × 100
... (5)
T1: Total tocotrienol concentration (ppm) of raw oil
T2: Total tocotrienol concentration (ppm) of refined fats and oils

(4) Metal ion concentration The metal ion concentration of the sample was measured by an atomic absorption method after ashing.

  Raw material oil (palm oil: Malaysian crude palm oil degummed; acid value 6-10, iodine value 50) 100 parts by weight of 99.5 vol% methanol 20 parts by weight was added with a heater. A column (diameter 8 cm, length 30 cm) packed at 60 ° C. and packed with an acidic gel cation exchange resin (Mitsubishi Chemical Co., Ltd., trade name Diaion SK104, degree of crosslinking (divinylbenzene) 4 wt%; 1.5 L) The refined fats and oils were obtained. The column temperature was 60 ° C., and the column residence time of the raw oil (2 kg) was 120 minutes. The acidic gel cation exchange resin was previously washed with 4 times (volume) of methanol.

  Purified fats and oils were obtained in the same manner as in Example 1 except that the amount of methanol added was 10 parts by weight with respect to 100 parts by weight of the raw material fats and oils.

  Purified fats and oils were obtained in the same manner as in Example 1 except that the amount of methanol added was 30 parts by weight with respect to 100 parts by weight of the raw fats and oils.

  Purified fats and oils were obtained in the same manner as in Example 1 except that an acidic gel cation exchange resin having a crosslinking degree of 6% by weight (trade name Diaion SK106, manufactured by Mitsubishi Chemical Corporation) was used.

  Purified fats and oils were obtained in the same manner as in Example 1 except that an acidic gel type cation exchange resin having a crosslinking degree of 8% by weight (trade name Diaion SK 1B, manufactured by Mitsubishi Chemical Corporation) was used.

  Purified fats and oils were obtained in the same manner as in Example 1 except that an acidic gel type cation exchange resin having a crosslinking degree of 10% by weight (trade name Diaion SK110, manufactured by Mitsubishi Chemical Corporation) was used.

(Comparative Example 1)
20 parts by weight of 99.5% by volume methanol is added to 100 parts by weight of raw material oil (palm oil; the same as in Example 1), and sulfuric acid (1.0% by weight added to the oil) is used as a catalyst at 60 ° C. for 120 minutes. While stirring, the free fatty acid in the raw material fat was esterified to obtain a purified fat.

(Comparative Example 2)
Instead of the acidic gel type cation exchange resin, except that an acid type solid cation exchange resin (manufactured by Mitsubishi Chemical Co., Ltd., trade name Diaion PK208, cross-linking degree 4% by weight) was used, in the same manner as in Example 1, A refined fat was obtained.

(Comparative Example 3)
Instead of the acidic gel type cation exchange resin, except that an acid type solid cation exchange resin (manufactured by Mitsubishi Chemical Co., Ltd., trade name Diaion PK212, degree of cross-linking 6% by weight) was used, A refined fat was obtained.

(Comparative Example 4)
In place of the acid gel type cation exchange resin, except that an acid type solid cation exchange resin (manufactured by Mitsubishi Chemical Co., Ltd., trade name Diaion PK216, degree of cross-linking 8 wt%) was used, A refined fat was obtained.

  The deoxidation rate, carotene disappearance rate, and tocotrienol disappearance rate of the refined fats and oils obtained in Examples 1 to 6 and Comparative Examples 1 to 4 were measured by the methods described above. The measurement results are shown in Tables 1 and 2 below. In addition, the following Table 1 is the said measurement result about Examples 1-6, and the following Table 2 is the said measurement result about Comparative Examples 1-4. Moreover, about Example 1, the metal ion concentration was also measured. The measurement results are shown in Table 3 below. The water content in the following Tables 1 and 2 indicates the water content in the cation exchange resin before treatment with methanol washing.

  From the said Table 1 and Table 2, it turned out that the refined fats and oils obtained in Examples 1-6 have low carotene disappearance rate and tocotrienol alteration rate compared with the refined fats and oils obtained in Comparative Example 1. Moreover, it turned out that the refined fats and oils obtained in Examples 1-6 have a high deoxidation rate compared with the refined fats and oils obtained in Comparative Examples 2-4.

  Moreover, as can be seen from Table 3 above, the metal ion concentration was below the detection limit by the production method of the present invention.

  According to the production method of the present invention, free fatty acids in raw fats and oils can be efficiently esterified, and when the raw fats and oils contain metal ions, they can also be removed. When useful components such as carotene and tocotrienol are contained in the coconut, its alteration and disappearance can be prevented. Therefore, if the production method of the present invention is applied to, for example, palm oil or the like, it is possible to obtain fats and oils that are excellent in oxidation stability and rich in useful components such as carotene and tocotrienol.

  The fats and oils obtained by the production method of the present invention can be further subjected to a transesterification reaction, and the obtained esters can be used as biodiesel fuel, for example, by mixing with light oil. Further, the ester can be further subjected to ethylene oxide addition, hydrogenation, higher alcoholation or sulfonation to synthesize a surfactant, and can be used as a cleaning agent, for example.

Claims (11)

  A method for producing fats and oils comprising a step of esterifying free fatty acids in raw fats and oils with alcohol, wherein the esterification step comprises adding alcohol to the raw fats and bringing them into contact with an acidic gel cation exchange resin The manufacturing method of the fats and oils which are.   The method for producing fats and oils according to claim 1, wherein the acidic gel type cation exchange resin has a degree of cross-linking of 3 to 10% by weight.   The method for producing fats and oils according to claim 1, wherein the esterification step is a step of passing the raw material fats and oils to which the alcohol is added through a column filled with the acidic gel cation exchange resin.   The method for producing fats and oils according to claim 3, wherein the column temperature is in a range of 40 to 70 ° C in passage of the raw oil and fat through the column.   The method for producing fats and oils according to claim 3, wherein the column residence time of the raw fats and oils is in the range of 100 to 480 minutes when the raw fats and oils pass through the column.   The method for producing fats and oils according to claim 1, wherein the addition amount of the alcohol is in the range of 5 to 30 parts by weight with respect to 100 parts by weight of the raw fats and oils.   The method for producing fats and oils according to claim 1, wherein the amount of water in the alcohol is 1500 ppm or less.   The manufacturing method of the fats and oils of Claim 1 in which the said alcohol contains methanol.   The manufacturing method of the fats and oils of Claim 1 which removes the metal ion contained in the said fats and oils further in the said esterification process.   Furthermore, the manufacturing method of the fats and oils of Claim 1 which has an alcoholysis process which adds alcohol to the fats and oils in which the free fatty acid was esterified by the said esterification process.   2. The method for producing fats and oils according to claim 1, wherein at least one selected from the group consisting of beef tallow, coconut oil, palm oil, palm kernel oil, rapeseed oil, soybean oil, sunflower oil, and corn oil is used as the raw material fat. .