JP2017039840A - Process for producing purified oil/fat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process for producing a purified oil/fat in which the content of glycidol and fatty acid ester thereof is reduced.SOLUTION: The present invention provides a process for producing purified oil/fat comprising a decolorization step of decolorizing a raw material oil/fat with a white clay having an average particle size of 21.0 μm or less. The white clay may be an acid white clay or an activated white clay. The present invention also provides a process for reducing glycidol and fatty acid ester thereof in purified oil/fat characterized by decolorizing raw material oil/fat with the white clay having an average particle size of 21.0 μm or less.SELECTED DRAWING: None

Description

  The present invention relates to a method for producing a refined fat.

  Fats and oils contain trace components that are considered to be related to physiological activity. Examples of such a trace component include glycidol and fatty acid esters thereof. It has been pointed out that the above ingredients may have nutritional problems, but if they are present in oils and fats such as vegetable oils that have been ingested from meals for many years, they may have an immediate effect on health. Is not considered, nor is the intake standard established. However, since there is a need for safer fats and oils, various methods for reducing the above components in the fats and oils have been proposed.

  It is known that glycidol and the like are produced by deodorizing fats and oils under a high temperature condition in the deodorization step. Therefore, for example, Patent Document 1 proposes a method for reducing glycidol and the like in fats and oils by decolorizing deodorized oil containing glycidol and the like with white clay having a pH of 5 to 7.

JP 2014-047290 A

  However, there is a further need for a method that can more effectively reduce the content of glycidol and the like in fats and oils by performing a treatment for reducing glycidol and the like in steps other than the deodorization step such as a decolorization step.

  This invention is made | formed in view of this situation, and it aims at providing the manufacturing method of refined fats and oils with which content of glycidol and its fatty acid ester was reduced.

  The inventors of the present invention have made extensive studies in order to solve the above problems. As a result, when the oil and fat decolorization step is performed in the presence of white clay having an average particle size of 21.0 μm or less, the deodorization step and the like are performed thereafter. However, the present inventors have found that an increase in the content of glycidol in fats and oils and fatty acid esters thereof (hereinafter, glycidol and fatty acid esters are also referred to as “glycidol etc.”) is suppressed, and the present invention is completed. It came to. Specifically, the present invention provides the following.

  (1) A method for producing refined fats and oils, including a decoloring step of decolorizing the raw material fats and oils with a clay having an average particle size of 21.0 μm or less.

  (2) The method for producing a refined fat according to (1), wherein the clay is acidic clay or activated clay.

  (3) The method for producing a refined fat according to (1) or (2), wherein the clay is pH 5.0 or less.

  (4) The method for producing a refined fat according to any one of (1) to (3), further including a deodorization step after the decolorization step.

  (5) A method for reducing glycidol and fatty acid esters thereof in refined fats and oils, wherein the raw fats and oils are decolorized with white clay having an average particle diameter of 21.0 μm or less.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of refined fats and oils with which content of glycidol and its fatty acid ester was reduced is provided.

  Hereinafter, embodiments of the present invention will be specifically described. The “oil and fat” in the present invention includes glyceride in which glycerin and 1 to 3 fatty acids are ester-bonded, and in addition to triglyceride (triacylglycerol), which is the main component of fat and oil, diglyceride (diacylglycerol). Glycerol) and monoglycerides (monoacylglycerol). In addition, the fats and oils in the present invention may contain components other than glycerides derived from animal and vegetable fats and oils (for example, plant sterols, lecithins, antioxidant components, pigment components, etc.). % Or more is preferably glyceride.

[Decolorization process]
The manufacturing method of refined fats and oils of this invention (henceforth "the manufacturing method of this invention") includes the decoloring process of decoloring raw material fats and oils with the white clay whose average particle diameter is 21.0 micrometers or less. Hereinafter, the decoloring step and the like will be described. In the present invention, “raw oil and fat” refers to fat and oil used in the decoloring step in the present invention, and “refined fat and oil” refers to fat and oil obtained through at least the decoloring step.

(White clay)
White clay has been used for the purpose of adsorbing and removing pigments and the like in fats and oils in the decolorization process of fats and oils. However, as a result of the study by the present inventors, when white clay having an average particle size of 21.0 μm or less is used in the decolorization step, unexpectedly, even if the deodorization step is subsequently performed, the inclusion of glycidol or the like in the fats and oils It was found that the increase in the amount was suppressed. That is, the decolorization process in the present invention is suitable as a pretreatment for the final stage (deodorization process or the like) of the oil and fat purification process.

  The white clay in the present invention is not particularly limited as long as the average particle diameter is 21.0 μm or less. "Average particle size" refers to the particle size at which the cumulative curve is 50% when the cumulative curve is determined based on the particle size distribution in the white clay dispersion and the total volume of the white clay is 100%. Can be identified by laser analysis.

  The average particle size of the clay is preferably 20 μm or less, more preferably 19 μm or less. The lower limit of the average particle size of the clay is not particularly limited, but is preferably 15 μm or more, more preferably 16 μm or more, from the viewpoint of good filterability.

  As the clay in the present invention, any clay may be used, and alkaline, neutral, or acidic clay can be used. From the viewpoint of facilitating decolorization of fats and oils, it is preferable to use acidic clay (acid clay, activated clay, etc.).

  The pH value of the clay in the present invention is preferably acidic (that is, less than pH 7.0) from the viewpoint that the lower the pH, the better the decolorization efficiency, more preferably pH 5.0 or less, still more preferably 4.0. It is as follows. The lower limit of the pH value of the clay is not particularly limited, but is preferably 2.0 or more, more preferably 3.0 or more.

  The pH value of the clay is specified by the method shown in the examples.

  The other conditions regarding the white clay in the present invention are not particularly limited, and can be appropriately adjusted according to the type of raw material fat used.

(Raw oil)
The raw oil / fat used in the decolorization step in the present invention may be an already refined fat / oil or an unrefined fat / oil.

  The oil and fat purification methods include chemical refining (chemical refining) and physical refining (physical refining), and fats and oils that have undergone any of the refining methods may be used as raw material fats and oils. Chemical refining is a method for refining fats and oils by subjecting crude oil obtained by pressing and extracting raw material plants to degumming, deoxidizing, decoloring, dewaxing, and deodorizing. Physical refining is a method of refining fats and oils by subjecting crude oil to degumming, decolorization, deoxidation, and deodorization. Oils and fats obtained through physical refining are also called RBD (Refined Bleached Deodorized) oils and fats. From the viewpoint that the effects of the present invention are easily achieved, the raw material fat is preferably RBD fat.

  The type of raw oil and fat is not particularly limited, and is not limited to vegetable oil (palm oil, rapeseed oil, soybean oil, rice oil, safflower oil, grape oil, sunflower oil, wheat germ oil, corn oil, cottonseed oil, sesame oil, peanut oil, Flux oil, sesame oil, olive oil, coconut oil, etc.), and edible fractionated oil (palm olein, palm stearin, palm super olein, palm mid fraction, etc.) obtained by separating vegetable oil and the like may be used. Moreover, the hydrogenated oil of said fats and oils, transesterified oil, and the edible oil (medium-chain fatty acid triglyceride etc.) manufactured by direct esterification reaction may be sufficient. The raw oil / fat may be a mixed oil of two or more of the above.

  The raw material fats and oils may contain additives such as antioxidants and emulsifiers as long as the effects of the present invention are not impaired.

(Conditions for decolorization process)
In the decolorization step in the present invention, the raw material fat is decolorized in the presence of the white clay. Known conditions can be adopted as other conditions in the decolorization step.

  The amount of white clay used in the decolorization step is not particularly limited and can be appropriately adjusted according to the degree of the effect to be obtained. For example, the more the amount of white clay used, or the lower the pH value of the white clay, the more effective the reduction effect of glycidol in fats and oils is increased. On the other hand, it may be preferably 0.1% by mass or more, and more preferably 0.5% by mass or more. Since the effect of the present invention is exhibited even if the amount of white clay used in the decolorization step is not excessive, the amount may be preferably 10% by mass or less, more preferably 5.0% by mass or less with respect to the charged amount.

  The method for decolorizing fats and oils in the decoloring step is not particularly limited, and may be a method used in a normal method for producing fats and oils. For example, white clay may be added to the oil and fat, and the oil and fat may be heated under stirring at 80 to 150 ° C. for 5 to 60 minutes. Moreover, you may make it fill with white clay in a filter or a column, and let oil and fat flow. After finishing the decolorization, the white clay can be removed from the fats and oils by filtration or the like to obtain a decolorized oil that has undergone a decolorization step.

[Deodorization process]
After the decolorization step, the obtained fats and oils may be subjected to a deodorization step. In the present invention, after the above decolorization step, by further performing a deodorization step, it is possible to remove odor components while suppressing an increase in glycidol, etc., so that the flavor is good and the content of glycidol and the like is reduced. Refined oils and fats can be obtained.

  Conditions in the deodorization step are not particularly limited, and may be conditions used in a normal method for producing fats and oils. For example, you may carry out by making fats and oils and water vapor | steam contact 160-260 degreeC for 10 to 180 minutes under reduced pressure (for example, 150-700 Pa). The deodorization time may be continuous or discontinuous. When the temperature condition in the deodorization process is low, an increase in glycidol or the like in the fat can be effectively suppressed even if the deodorization time is short.

  The amount of water vapor that is brought into contact with fats and oils in the deodorization step is not particularly limited, but is preferably 0.5% by mass or more, more preferably 1.0% by mass with respect to the amount of fats and oils (preparation amount) to be treated in the deodorization step. It may be the above. The upper limit of the amount of water vapor is preferably 10% by mass or less, more preferably 8% by mass or less, with respect to the charged amount.

  In the deodorization step, an antioxidant (such as citric acid) or the like may be appropriately added to the oil.

[Specification of content of glycidol, etc. in refined fats and oils]
According to the production method of the present invention, it is possible to obtain a refined fat with a reduced content of glycidol and the like. Content of glycidol etc. in fats and oils is specified by the method described in the Example.

  Hereinafter, although it demonstrates still in detail based on the Example of this invention, this invention is not limited to these description at all.

  For 2.0 kg of RBD palm oil (produced in Malaysia, corresponding to raw oil and fat), in the presence of any of the activated clays listed in Table 1, the decolorization step and the deodorization step are performed under the conditions described in Table 2. A refined fat was obtained. As shown in Table 1, the activated clay used in Examples and Comparative Examples has substantially the same characteristics except for the average particle size.

  In addition, the measuring method of the item in Table 1 is as follows.

(moisture)
The clay was dried at 110 ° C., and the difference between the mass of the clay before drying and the mass of the clay after drying was divided by the mass of the clay before drying to calculate.

(Acid value)
It was measured based on the Japan Oil Chemists' Society edited by “Standard Analysis Method for Oils and Fats 2.3.1-1996”.

(Average particle size)
Measurement was performed by laser analysis using a Mastersizer 2000 (Malvenrn). Water was used as a dispersion medium.

(Solid acid amount)
It measured by n-butylamine titration method (H0 <=- _3.0 ).

(Specific surface area)
It was calculated by the BET method.

(PH)
A 5% by mass suspension was prepared by suspending white clay in water and measured with a pH meter.

(The bulk density)
It was measured by the iron cylinder method.

(Pore volume)
Based on the BJH method, the amount of adsorption was calculated.

  In each step of the decolorization step and the deodorization step, fats and oils (referred to as “decoloring oil” and “deodorizing oil”, respectively) were collected, and the fats and oils were analyzed by the following methods. The results are shown in Table 3. The acid value was measured by the same method as described above.

(Hue)
Based on the Robibond method (Japan Oil Chemical Association, Standard Oil Analysis Test Method 2.2.1.1), the raw material oil and fat were measured using a 25.4 mm cell, and the decolorized oil and deodorized oil were measured using a 133.4 mm cell.

(Peroxide value)
It was measured based on the standard fat and oil analysis test method 4-2000.

(Quantification of MCPD-FS)
The total amount of 3-chloropropane-1,2-diol (hereinafter also referred to as “3-MCPD”), fatty acid ester of 3-MCPD, glycidol and fatty acid ester of glycidol in each refined oil (the total amount is referred to as “MCPD-FS Was determined according to the German official method (DGF Standard Methods C-III 18 (09)).

  Specifically, 50 μL of an internal standard substance (3-MCPD-d5 20 μg / mL solution) is added to 100 mg of each refined fat and oil, and then 1 mL of sodium methoxide solution (0.5 mol / L methanol) is added to the room temperature. The ester was saponified and decomposed. Next, 3 mL of brine (20%) containing a small amount of acetic acid and 3 mL of hexane were added to and mixed with this, and then hexane was removed. Thereafter, it was derivatized with 250 μL of an aqueous phenylboric acid solution (25%), extracted with 2 mL of hexane, and measured with a gas chromatograph mass spectrometer.

  Using the chromatogram obtained by the measurement of the gas chromatograph mass spectrometer, the ionic strengths of 3-MCPD-d5, which is an internal standard, and 3-MCPD are compared, and 3-MCPD and 3-MCPD in fats and oils are compared. The total amount of fatty acid ester, glycidol and fatty acid ester of glycidol was calculated in terms of free 3-MCPD.

  Further, the value obtained by subtracting the MCPD-FS of the decolorized oil from the MCPD-FS of the deodorized oil is shown in Table 3 as “MCPD-FS difference between the deodorized oil and the decolorized oil”.

(Quantification of True MCPD)
The quantification of 3-MCPD and the total amount of fatty acid ester of 3-MCPD in each refined fat (the total amount is referred to as “True MCPD”) was determined by a modification of the German official method (DGF Standard Methods C-III 18 (09)). Made in compliance with the law.

  Specifically, 50 μL of an internal standard substance (3-MCPD-d5 20 μg / mL solution) is added to 100 mg of each refined fat and oil, and then 1 mL of sodium methoxide solution (0.5 mol / L methanol) is added to the room temperature. The ester was saponified and decomposed. Next, 3 mL of an aqueous sodium bromide solution (50%) containing a small amount of acetic acid and 3 mL of hexane were added thereto and mixed, and then hexane was removed. Thereafter, it was derivatized with 500 μL of phenylboric acid aqueous solution (12.5%), extracted with 2 mL of hexane, and measured with a gas chromatograph mass spectrometer.

  Using the chromatogram obtained by the measurement of the gas chromatograph mass spectrometer, the ionic strength of 3-MCPD-d5 which is an internal standard and 3-MCPD are compared, and 3-MCPD and 3-MCPD in the glyceride composition are compared. The total amount of the fatty acid ester was calculated in terms of free 3-MCPD.

  Further, the value obtained by subtracting the True MCPD of the decolorizing oil from the True MCPD of the deodorizing oil is shown in Table 3 as “True MCPD difference between the deodorizing oil and the decoloring oil”.

(Calculation of glycidol amount)
Based on the MCPD-FS and True MCPD values specified by the above method, the amount of glycidol in each refined fat was calculated based on the following formula.
Amount of glycidol = (MCPD-FS-True MCPD) × 0.67
In the above formula, “0.67” is a value obtained by dividing the molecular weight of glycidol (74.1) by the molecular weight of 3-MCPD (110.54).

  Furthermore, the value obtained by subtracting the amount of glycidol of the decolorized oil from the amount of glycidol of the deodorized oil is shown in Table 3 as “the glycidol difference between the deodorized oil and the decolorized oil”.

  As shown in “Glycidol difference between deodorized oil and decolorized oil” in Table 3, in Examples using activated clay having an average particle size of 17.3 μm, the increase in the amount of glycidol after the deodorizing process was reduced. It was. As shown in “Glycidol” in the sections of “Decolorized oil” and “Deodorized oil” in Table 3, there is almost no difference in the amount of glycidol in Examples and Comparative Examples in decolorized oil, but in Deodorized oil, The increase in the amount of glycidol in the example is suppressed more than in the comparative example. That is, according to this invention, it turns out that the increase in glycidol etc. in a deodorizing process can be suppressed by performing the decoloring process using the white clay which has a predetermined average particle diameter. Moreover, about the hue, in the deodorized oil, the direction of the Example was lighter than the comparative example, and the refined | purified fats and oils preferable in an external appearance were obtained.

  On the other hand, as shown in “Acid Value” and “Peroxide Value” in Table 3, the average particle size of the activated clay hardly affected these items.

  In addition, although data is not shown, in the above examples and comparative examples, when the addition amount of the activated clay was changed to 0.8% by mass with respect to the charged amount, the same tendency as described above was shown, and the average particle size When activated clay with 17.3 μm was used, the amount of glycidol after the deodorizing step was reduced.

Claims (5)

  A method for producing refined fats and oils, comprising a decoloring step of decolorizing raw material fats and oils with white clay having an average particle diameter of 21.0 μm or less.   The method for producing refined fats and oils according to claim 1, wherein the clay is acidic clay or activated clay.   The said white clay is a manufacturing method of the refined fats and oils of Claim 1 or 2 which are pH 5.0 or less.   The manufacturing method of the refined fats and oils of any one of Claim 1 to 3 further including a deodorizing process after the said decoloring process.   A method for reducing glycidol and fatty acid esters thereof in purified fats and oils, characterized in that the raw oils and fats are decolorized with white clay having an average particle diameter of 21.0 μm or less.