JP6639149B2 - Method for producing refined fats and oils - Google Patents

Description

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

  Fats and oils contain trace components that are considered to be related to physiological activities. Examples of such a trace component include glycidol and its fatty acid ester. It has been pointed out that the above ingredients may have nutritional problems, but if they are present in fats and oils such as vegetable oils that have been ingested from foods for many years, they will immediately affect health. Is not considered, nor is there a standard for intake. However, there is a need for more safe fats and oils, and various methods for reducing the above components in fats and oils have been proposed.

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

JP 2014-047290 A

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

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a method for producing a refined oil or fat in which the content of glycidol and its fatty acid ester is reduced.

  Means for Solving the Problems The present inventors have conducted intensive studies in order to solve the above-mentioned problems. As a result, when the decolorizing step of fats and oils is performed in the presence of clay having an average particle diameter of 21.0 μm or less, the deodorizing step is performed. However, it has been found that an increase in the content of glycidol and its fatty acid ester (hereinafter, glycidol and its fatty acid ester are collectively referred to as “glycidol or the like”) in the fat or oil is suppressed, thereby completing the present invention. Reached. Specifically, the present invention provides the following.

  (1) A method for producing a purified oil and fat, comprising a decolorizing step of decolorizing a raw oil and fat with clay having an average particle size of 21.0 μm or less.

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

  (3) The method according to (1) or (2), wherein the clay has a pH of 5.0 or less.

  (4) The method for producing a purified oil or fat according to any one of (1) to (3), further including a deodorizing step after the decolorizing step.

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

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

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

[Decoloring process]
The method for producing a refined oil / fat of the present invention (hereinafter, also referred to as the “production method of the present invention”) includes a decolorizing step of decolorizing raw oil / fat with clay having an average particle size of 21.0 μm or less. Hereinafter, the decolorization step and the like will be described. In the present invention, "raw material fat" refers to a fat or oil that is subjected to the decolorizing step in the present invention, and "purified fat or oil" refers to a fat or oil obtained through at least the decolorizing step.

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

  The clay in the present invention is not particularly limited as long as the average particle size is 21.0 μm or less. “Average particle size” refers to the particle size at which the cumulative curve becomes 50% when the cumulative curve is determined based on the particle size distribution of the clay in the dispersion liquid and the total volume of the clay is 100%; It 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, and 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 may be used. It is preferable to use acidic clay (acid clay, activated clay, etc.) from the viewpoint of facilitating decolorization of fats and oils.

  The pH value of the clay in the present invention is preferably acidic (that is, less than pH 7.0), more preferably pH 5.0 or less, and still more preferably 4.0, from the viewpoint that the lower the pH, the better the decolorization efficiency. 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, and more preferably 3.0 or more.

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

  Other conditions relating to the clay in the present invention are not particularly limited, and can be appropriately adjusted according to the type of the raw material fat or the like to be used.

(Raw material fats and oils)
Raw oils and fats to be subjected to the decolorizing step in the present invention may be oils and fats that have already been refined or oils and fats that have not been refined.

  There are two methods for purifying fats and oils: chemical refining (chemical refining) and physical refining (physical refining). Fats and oils that have undergone any of the refining methods may be used as raw fats and oils. Chemical refining is a method of purifying oils and fats by subjecting crude oil obtained by squeezing and extracting raw material plants to degumming treatment, deacidification treatment, decolorization treatment, dewaxing treatment, and deodorization treatment. Physical refining is a method of purifying oils and fats by subjecting crude oil to degumming, decolorization, deacidification, and deodorization. The fats and oils obtained through physical refining are also called RBD (Refined Bleached Deodorized) fats and oils. From the viewpoint that the effects of the present invention are easily exerted, the raw material fat is preferably RBD fat.

  The type of raw material fats and oils is not particularly limited, and vegetable oils (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, perilla oil, olive oil, coconut oil, etc.), and edible fractionated oils (palm olein, palm stearin, palm super olein, palm mid fraction, etc.) obtained by separating vegetable oils and the like may be used. Further, hydrogenated oils, transesterified oils, and edible oils (medium chain fatty acid triglycerides, etc.) produced by the direct esterification reaction may be used. The raw fat or oil may be a mixed oil of two or more of the above fats and oils.

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

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

  The amount of the clay used in the decolorizing step is not particularly limited, and can be appropriately adjusted according to the degree of the effect to be obtained. For example, the greater the amount of clay used, or the lower the pH value of the clay, the greater the effect of reducing glycidol and the like in the fats and oils. On the other hand, it may be preferably 0.1% by mass or more, more preferably 0.5% by mass or more. Since the effects of the present invention can be obtained even if the amount of clay used in the decoloring step is not excessive, it may be preferably 10% by mass or less, more preferably 5.0% by mass or less based on the charged amount.

  The method for decolorizing the fat or oil in the decoloring step is not particularly limited, and may be a method used in a normal method for producing fat or oil. For example, the clay may be added to the fat or oil, and the fat or oil may be heated with stirring at 80 to 150 ° C. for 5 to 60 minutes under reduced pressure. Further, a filter or a column may be filled with clay to allow the passage of oils and fats. After the decolorization, the clay is removed from the fat or oil by filtration or the like, and a decolorized oil that has undergone a decolorization step can be obtained.

[Deodorization step]
After the decolorizing step, the obtained fat or oil may be subjected to a deodorizing step. In the present invention, after the above decolorizing step, by further performing a deodorizing step, it is possible to remove odor components and the like while suppressing an increase in glycidol and the like, so that the flavor is good, and the content of glycidol and the like is reduced. A refined oil and fat can be obtained.

  The conditions in the deodorizing step are not particularly limited, and may be the conditions used in an ordinary method for producing fats and oils. For example, it may be performed by bringing oil and fat into contact with steam under reduced pressure (for example, 150 to 700 Pa) at 160 to 260 ° C. for 10 to 180 minutes. The deodorization time may be continuous or discontinuous. When the temperature conditions in the deodorization step are low, even if the deodorization time is short, it is possible to effectively suppress an increase in glycidol or the like in the fat or oil.

  The amount of steam to be brought into contact with the fat or oil in the deodorizing step is not particularly limited, but is preferably 0.5% by mass or more, more preferably 1.0% by mass, based on the amount of fat or oil to be treated in the deodorizing step (prepared amount). It may be the above. The upper limit of the amount of water vapor may be preferably 10% by mass or less, more preferably 8% by mass or less, based on the charged amount.

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

[Specification of content of glycidol, etc. in refined fats and oils]
ADVANTAGE OF THE INVENTION According to the manufacturing method of this invention, the refined oil and fat with which content of glycidol etc. was reduced can be obtained. The content of glycidol and the like in fats and oils is specified by the method described in Examples.

  Hereinafter, the present invention will be described in more detail based on examples of the present invention, but the present invention is not limited to these descriptions.

  A decolorizing step and a deodorizing step were performed on 2.0 kg of RBD palm oil (originating in Malaysia, corresponding to raw oils and fats) in the presence of any of the activated clay shown in Table 1 under the conditions shown in Table 2. A purified fat was obtained. As shown in Table 1, the activated clay used in Examples and Comparative Examples has almost 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 and calculated.

(Acid value)
It was measured based on "Standard Oil and Fat Analysis Test Method 2.3.1-1996" edited by Japan Oil Chemists' Society.

(Average particle size)
The measurement was performed by a laser analysis method using Mastersizer 2000 (manufactured by Malvenrn). In addition, water was used as a dispersion medium.

(Solid acid content)
It was measured by the n-butylamine titration method (H ₀ ≦ −3.0).

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

(PH)
The clay was suspended in water to prepare a 5% by mass suspension, and the suspension was measured with a pH meter.

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

(Pore volume)
It was calculated from the amount of adsorption based on the BJH method.

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

(Hue)
Based on the Lovibond method (Nippon Oil Chemistry Association, Standard Fat and Oil Analysis Test Method 2.2.1.1), the raw fat was 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 fat (the total amount is referred to as “MCPD-FS”). ) Was performed according to the German official method (DGF Standard Methods C-III 18 (09)).

  Specifically, 50 μL of an internal standard substance (20 μg / mL solution of 3-MCPD-d5) was added to 100 mg of each purified fat and oil, and then 1 mL of a sodium methoxide solution (0.5 mol / L methanol) was added. To perform saponification decomposition of the ester. Next, 3 mL of a saline solution (20%) containing a small amount of acetic acid and 3 mL of hexane were added thereto and mixed, and then the hexane was removed. Then, it was derivatized with 250 μL of an aqueous phenylboric acid solution (25%), extracted with 2 mL of hexane, and measured by a gas chromatograph mass spectrometer.

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

  Further, Table 3 shows a value obtained by subtracting MCPD-FS of the decolorizing oil from MCPD-FS of the deodorizing oil as “MCPD-FS difference between the deodorizing oil and the decolorizing oil”.

(Quantification of True MCPD)
The quantification of the total amount of 3-MCPD and the 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)). Performed according to law.

  Specifically, 50 μL of an internal standard substance (20 μg / mL solution of 3-MCPD-d5) was added to 100 mg of each purified fat and oil, and then 1 mL of a sodium methoxide solution (0.5 mol / L methanol) was added. To perform saponification decomposition of the ester. Next, 3 mL of an aqueous solution of sodium bromide (50%) containing a trace amount of acetic acid and 3 mL of hexane were added and mixed, and then the hexane was removed. Then, it was derivatized with 500 μL of phenylboric acid aqueous solution (12.5%), extracted with 2 mL of hexane, and measured by 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 as an internal standard and 3-MCPD was compared, and 3-MCPD and 3-MCPD in the glyceride composition were compared. Was calculated in terms of free 3-MCPD.

  Further, Table 3 shows a value obtained by subtracting True MCPD of the decolorizing oil from True MCPD of the deodorizing oil as “True MCPD difference between the deodorizing oil and the decolorizing oil”.

(Calculation of glycidol amount)
Based on the values of MCPD-FS and True MCPD specified by the above method, the amount of glycidol in each purified fat was calculated based on the following formula.
Glycidol amount = (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).

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

  As shown in “Difference in glycidol between deodorized oil and decolorized oil” in Table 3, in Examples using activated clay having an average particle size of 17.3 μm, an increase in the amount of glycidol after the deodorization step was reduced. I was As shown in “Glycidol” in the section “Decolorized oil” and “Deodorized oil” in Table 3, there is almost no difference in the amount of glycidol in the Examples and Comparative Examples in the decolorized oil. The increase in the amount of glycidol in the examples is more suppressed than in the comparative examples. That is, according to the present invention, it can be seen that by performing the decolorizing step using white clay having a predetermined average particle size, an increase in glycidol and the like in the deodorizing step can be suppressed. Further, with respect to the hue, in the case of the deodorized oil, the Example was lighter in color than the Comparative Example, and a purified oil / fat having a favorable appearance was 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.

  Although data is not shown, in the above Examples and Comparative Examples, when the amount of activated clay was changed to 0.8% by mass with respect to the charged amount, the same tendency as described above was exhibited. When activated clay having a particle size of 17.3 μm was used, the amount of glycidol after the deodorization step was reduced.

Claims (5)

A decolorizing step of decolorizing the raw oil or fat with white clay having an average particle size of 21.0 μm or less;
A deodorizing step of deodorizing the fats and oils after the decolorizing step at 250 to 260 ° C,
The raw material fat is RBD fat, and is a vegetable oil and / or an edible fractionated oil obtained by fractionating the vegetable oil.
Production method of refined fats and oils.   The method for producing a refined oil and fat according to claim 1, wherein the clay is acid clay or activated clay.   The method for producing a purified fat or oil according to claim 1 or 2, wherein the clay has a pH of 5.0 or less. The method for producing a purified fat or oil according to any one of claims 1 to 3 , wherein an amount of the clay used in the decolorizing step is 1.0 to 10% by mass based on an amount of the raw material fat and oil . Including decolorizing the raw material fat with white clay having an average particle size of 21.0 μm or less, and then deodorizing at 250 to 260 ° C.
The raw material fat is RBD fat, and is a vegetable oil and / or an edible fractionated oil obtained by fractionating the vegetable oil.
A method for reducing glycidol and its fatty acid ester in refined fats and oils.