CN114761524A

CN114761524A - Method for producing purified oil or fat

Info

Publication number: CN114761524A
Application number: CN202080064618.8A
Authority: CN
Inventors: 城户裕喜; 西泽大树; 山下敦史; 茂木和之; 根津亨
Original assignee: Adeka Corp
Current assignee: Adeka Corp
Priority date: 2019-10-25
Filing date: 2020-10-23
Publication date: 2022-07-15
Also published as: WO2021079989A1; JPWO2021079989A1

Abstract

Provided is a method for producing a purified fat or oil, whereby a fat or oil having a sufficiently reduced content of MCPD-type and glycidyl oils can be efficiently obtained. The method for producing a purified oil or fat comprises: and (3) contact treatment of contacting the oil and fat with clay and zeolite.

Description

Method for producing purified oil or fat

Technical Field

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

Background

In order to improve the quality of fats and oils represented by flavor, oxidation stability, and the like, so-called crude oils collected from animals and plants are purified, and the purification includes: degumming, deoxidizing, decoloring, deodorizing and the like. Recently, RBD (refined harvested purified) oils and fats, which are oils and fats purified by physical refining, and NBD (refined harvested purified) oils and fats, which are oils and fats purified by chemical refining, have been sold, but even in the case of RBD oils and fats and NBD oils and fats, sufficient purification is not usually performed from the viewpoint of flavor, oxidation stability, and the like.

Therefore, in order to further improve the quality of fats and oils represented by flavor, oxidation stability, and the like, fats and oils subjected to primary purification, for example, RBD fats and oils or NBD fats and oils, are often subjected to secondary purification.

Here, in recent years, with the progress of analytical techniques, it has been found that purified oils and fats including RBD oils and fats and NBD oils and fats contain: chloropropanediols and fatty acid esters thereof (hereinafter, these are collectively referred to as "MCPD"), such as 3-chloropropane-1, 2-diol (hereinafter, referred to as "3-MCPD") and 2-chloropropane-1, 3-diol (hereinafter, referred to as "2-MCPD"), and glycidol and fatty acid esters thereof (hereinafter, these are collectively referred to as "glycidols"). MCPD and glycidol are considered to be substances produced from lipids and chloride ions in fats and oils when the fats and oils are subjected to high temperatures in a purification process, for example, in a deodorization step. MCPD and glycidol have risks of adverse health effects, and various studies have been made to reduce the content of MCPD and glycidol in fats and oils.

For example, as one of methods for reducing the content of MCPDs in fat and oil, a method using an adsorbent is given. This method is a method for reducing and removing MC PDs in a fat or oil produced in a purification process using an adsorbent. For example, patent document 1 proposes: a method for reducing the content of MCPD in a fat or oil, which has undergone a decoloring step and a deodorizing step, by bringing the fat or oil into contact with silica gel and/or alkaline activated carbon. Patent document 2 proposes: a process for producing an oil or fat which reduces MCPD levels by bringing an oil or fat into contact with 1 or more kinds of inorganic powders selected from boehmite and hydrotalcite under a certain temperature condition.

In recent years, use of a mixture obtained by adding another component to an adsorbent has also been studied. Patent document 3 proposes a method for producing a purified glyceride composition using a mixture of activated clay and potassium carbonate, and patent document 4 proposes a decolorizer for purified oils and fats using a mixture of activated clay and a silica magnesium oxide preparation.

Non-patent document 1 shows: and a method for removing 3-MCPD fatty acid ester and derivatives thereof from the purified fat or oil by using various adsorbents such as amorphous magnesium silicate and zeolite.

Documents of the prior art

Patent literature

Patent document 1: international publication No. 2011/040539

Patent document 2: japanese laid-open patent publication No. 2015-067692

Patent document 3: japanese patent laid-open publication No. 2018-095758

Patent document 4: japanese patent laid-open publication No. 2016-040366

Non-patent document

Non-patent document 1: eur, J.Lipid Sci.Technol.2011, 113, 387-

Disclosure of Invention

Technical problem to be solved by the invention

The method of contacting with the adsorbent is easily introduced into a conventionally known purification step of fats and oils, but has a problem that it is difficult to sufficiently reduce the content of MCPDs in the fats and oils. In particular, in the method described in patent document 1, since the treatment by the adsorbent is the final step, it is easy to impart the flavor derived from the adsorbent to the fat or oil.

Further, the method described in patent document 2 has a problem that it cannot be used for producing edible fat or oil because it uses an adsorbent that cannot be used for producing food. Further, the method described in patent document 3 has a problem that saponification and decomposition may occur simultaneously with purification because potassium carbonate, which exhibits strong basicity in an aqueous solution, is used. Further, the oils and fats discussed in the examples are not actually subjected to deodorization treatment, and it is not disclosed whether MCPD is sufficiently reduced or not even when the method for producing oils and fats described in patent document 3 is used.

Further, the method of patent document 4 aims at performing deodorization treatment at a low temperature in a short time, and is used for decoloring RBD palm oil, and even if an increase in so-called MCPD and glycidyl compounds associated with the deodorization treatment can be prevented, it is difficult to reduce MCPD and glycidyl compounds that have been generated.

Non-patent document 1 shows that 3-MCPD can be reduced to about 4ppm by adding an adsorbent such as amorphous magnesium silicate or zeolite to an oil or fat in an amount of 10 mass%, but the use of a large amount of such an adsorbent has a problem in terms of cost. Further, although the adsorbent is industrially removed by filtration when the adsorbent is removed from the oil or fat, the method described in non-patent document 1 uses a large amount of adsorbent to remove 3-MCPD, and therefore the filtration efficiency and the yield of the oil or fat tend to be low, and there is a problem in terms of the production efficiency when the method is applied to the industrial production of the oil or fat.

Therefore, the technical problem solved by the invention is that: provided is a method for producing a purified fat or oil, whereby a fat or oil having a sufficiently reduced content of MCPD-based and glycidyl compounds can be efficiently obtained.

Means for solving the problems

The present inventors have conducted intensive studies to solve the problems and, as a result, have found that: the present inventors have completed the present invention by making it possible to reduce MCPD and glycidol by a contact treatment with clay and zeolite in the production of purified oils and fats.

The present invention provides the following.

<1> a method for producing a purified oil or fat, which comprises: and (3) contact treatment of contacting the oil and fat with clay and zeolite.

<2> the method according to <1>, wherein,

in the contact treatment, the fat is simultaneously contacted with the clay and the zeolite.

<3>, the method according to <1> or <2>, wherein,

the temperature of the grease in the contact treatment is 50-260 ℃.

<4> the method according to any one of <1> to <3>, wherein,

in the contact treatment, 0.1 to 3.5 parts by mass of zeolite is used per 100 parts by mass of the fat or oil.

<5> the method according to any one of <1> to <4>, wherein,

the clay is activated clay.

<6> the method according to any one of <1> to <5>, wherein,

the zeolite is selected from more than 1 of natural zeolite and synthetic zeolite.

<7> the method according to any one of <1> to <6>, further comprising: the contact-treated fat or oil is subjected to deodorization treatment for deodorization.

<8> the method according to <7>, wherein,

the temperature of the grease in the deodorization treatment is 180-270 ℃.

<9> and the method according to any one of <1> to <8>, wherein the fat or oil subjected to the deodorization step is subjected to at least 1 time.

<10> and a purified oil or fat obtained by the method according to any one of <1> to <9>, wherein the total content of chloropropanediols and fatty acid esters thereof is 4 mass ppm or less.

<11> and a purified oil or fat obtained by the method according to any one of <1> to <9>, wherein the total content of glycidol and fatty acid esters thereof is 3 mass ppm or less.

<12> A process for reducing chloropropanediol and fatty acid esters thereof or glycidol and fatty acid esters thereof in oils and fats, which comprises: and (3) contact treatment of contacting the oil and fat with clay and zeolite.

<13> A decolorizer for fats and oils, wherein,

the zeolite is contained in an amount of 0.1 to 2.5 parts by mass based on 1 part by mass of the clay.

<14> a reducing agent for chloropropanediol and fatty acid esters thereof or glycidol and fatty acid esters thereof in oils and fats, wherein,

ADVANTAGEOUS EFFECTS OF INVENTION

The method for producing a purified oil or fat of the present invention can efficiently produce an oil or fat having a sufficiently reduced content of MCPD and glycidyl compounds.

Detailed description of the invention

Hereinafter, the present invention will be described in detail with reference to preferred embodiments. The present invention is not limited to the following cases, and each constituent element may be appropriately modified within a range not departing from the gist of the present invention.

[ Process for producing purified oils and fats ]

The method for producing a purified oil or fat of the present invention (hereinafter, also simply referred to as "the method for producing the present invention") includes: and (3) contact treatment of contacting the oil and fat with clay and zeolite.

The order of contacting the clay and zeolite with the oil and fat is not particularly limited, and specific methods of the contact treatment include the following (1) to (4).

< case where Clay and zeolite were brought into contact with each other >

(1) After the contact treatment of bringing the clay into contact with the oil or fat, the contact treatment of bringing the zeolite into contact is performed.

(2) After the contact treatment of bringing the zeolite into contact with the oil or fat, the contact treatment of bringing the clay into contact is performed.

< case where Clay and zeolite were simultaneously contacted >

(3) The clay and zeolite are continuously charged with the oil and fat in an arbitrary order, and subjected to a contact treatment by simultaneous contact.

(4) A contact treatment is performed by bringing a mixture of clay and zeolite, which has been prepared in advance, into contact with an oil or fat.

The contact treatment of bringing clay and zeolite into contact with the oil or fat may be carried out by any method, and either a batch type or a continuous type may be used, and from the viewpoint of enabling a large amount of oil or fat to be treated at one time, it is preferable to carry out the contact treatment in a batch type.

In the case of the batch process, examples thereof include: (I) a method of treating an oil or fat heated to a predetermined temperature by adding one or both of clay and zeolite to the oil or fat; (II) a method of charging one or both of clay and zeolite into the fat and oil, and then heating the fat and oil to a predetermined temperature, and in either case, it is preferable to charge one or both of clay and zeolite into the fat and oil, and then stir the fat and oil during the contact treatment to disperse the clay and zeolite in the fat and oil.

In the case of performing the contact treatment by the methods (1) and (2), a filtration step may be performed between the contact treatment in which clay is contacted and the contact treatment in which zeolite is contacted, and after the clay or zeolite is filtered off, the process may be shifted to the next contact treatment.

In the case of the contact treatment by the method (4), it is preferable to mix the clay and the zeolite by dry mixing when preparing a mixture.

In the case of performing the contact treatment of bringing clay and zeolite into contact with an oil or fat, it is preferable to bring clay and zeolite into contact with the oil or fat simultaneously by any of the above-mentioned methods (3) and (4) from the viewpoint of obtaining an oil or fat excellent in flavor and color tone and from the viewpoint of removing MCPDs and glycidols from the oil or fat.

In addition, from the viewpoint of being able to set the temperature of the oil and fat at the time of contact treatment described later low and further improve the oxidation stability of the oil and fat over time, it is preferable to contact the clay and zeolite with the oil and fat simultaneously by any of the above-mentioned methods (3) and (4).

Hereinafter, clay and zeolite used for the contact treatment will be described.

-clay-

As the clay used in the present invention, a naturally-produced acid clay (montmorillonite clay) or an activated clay obtained by subjecting an acid clay to an acid treatment with an inorganic acid such as sulfuric acid or hydrochloric acid can be used.

In particular, in the present invention, it is preferable to use activated clay having a porous structure with a large specific surface area in the acid treatment. The specific surface area of the activated clay is preferably 50 to 400m, although it varies depending on the degree of acid treatment and the like²The acidity of activated clay (KOHmg/g) is preferably 2.50 or less.

Activated clay contains SiO as a general chemical component₂、Al₂O₃、Fe₂O₃CaO, MgO, etc., SiO₂With Al₂O₃Mass ratio of (SiO)₂/Al₂O₃Ratio) is preferably in the range of 3 to 12, more preferably in the range of 4 to 10. Further, it preferably contains Fe₂O₃1 to 5 mass%, CaO 0 to 1.5 mass%, and MgO 1 to 7 mass%.

Commercially available products of acid clay used in the present invention include: examples of commercially available activated clay used in the present invention include MIZUKA ACE #20, MIZUKA ACE #300, MIZUKAACE #400, and MIZULITE (all manufactured by zeo chemical industries, ltd.): GALLEON EARTH V2R, GALLEON EARTH V2, GALLEON EARTH NVZ, GALLEON EARTH NV, etc. (all manufactured by ZUIZE CHEMICAL CO., LTD.).

Zeolite-

The Zeolite used in the present invention is an aluminosilicate mineral also referred to as Zeolite, which has a porous structure derived from a crystal structure.

Zeolites are roughly classified into three types, i.e., natural zeolites, synthetic zeolites, and artificial zeolites, depending on their sources. The synthetic zeolite in the present invention is artificially synthesized from a raw material such as pure silicic acid or aluminum hydroxide, and has a higher purity than natural zeolite. The artificial zeolite is artificially synthesized from a raw material such as lime char.

In the present invention, the effect of the present invention can be obtained by using 1 or more selected from natural zeolites, synthetic zeolites, and artificial zeolites.

The zeolite contains SiO as a general chemical component₂、Al₂O₃、Fe₂O₃、CaO、K₂O and Na₂O, and the like.

The zeolite used in the method for producing a purified oil or fat of the present invention is not particularly limited, and for example, a zeolite having SiO can be used₂With Al₂O₃Mass ratio of (SiO)₂/Al₂O₃Ratio) of 2 to 12.

When the purified oil or fat obtained by the production method of the present invention is used as an edible oil or fat, it is preferable to use 1 or more kinds selected from natural zeolites and synthetic zeolites from the viewpoint of reducing MCPD and glycidyl groups. As the zeolite, a calcined zeolite calcined during the production thereof may be used. From the viewpoint of further reducing MCPD and glycidyl groups, it is preferable to use an unfired zeolite.

Commercially available products of the zeolite used in the present invention include SGW, SGW-B4, calcined SGW and the like (both manufactured by ZEEKLITE corporation), SP #600 and the like (manufactured by Nindon Kalite Co., Ltd.), IZUKALITE and the like (manufactured by IZUKA, Ltd.), SU and the like (manufactured by ZEO, Ltd.), and the like.

The clay and zeolite have different "structures" and "pore sizes". Specifically, the clay has, for example, a smectite structure, and the average pore diameter thereof is preferably

Left and right. On the other hand, the zeolite has, for example, a clinoptilolite structure, a mordenite structure, and the average pore diameter thereof is preferably not sufficient

The selected zeolite may have a mordenite structure alone, a clinoptilolite structure alone, or both of these structures. The structure of zeolite is determined by X-ray analysis, and clinoptilolite structure, mordenite structure, and a mixture thereof are determined from the change in the shape of the peak due to heating.

The shape of the clay and zeolite used in the present invention is not particularly limited, and various shapes such as powder, block, bead and granule can be adopted. The clay and zeolite are preferably in a powder form from the viewpoint of increasing the contact area with the fat or oil. From the viewpoint of particularly excellent effect of reducing MCPD and glycidyl compounds, it is preferable to use powdery zeolite having an average particle diameter of, for example, 200 μm or less, 150 μm or less, 100 μm or less, or 50 μm or less, and more preferably to use powdery zeolite having an average particle diameter of 15 μm or less or 12 μm or less.

The amount of clay and zeolite used

The amount of clay used is preferably 0.25 parts by mass or more, more preferably 0.5 parts by mass or more, and still more preferably 0.75 parts by mass or more, and 0.8 parts by mass or more, or 1.0 part by mass or more, per 100 parts by mass of the fat or oil, from the viewpoint of obtaining a fat or oil having an excellent color tone and sufficiently reducing MCPD and glycidyl groups. The upper limit of the amount of clay used is not particularly limited, and is preferably 4.5 parts by mass or less, more preferably 3.0 parts by mass or less, further preferably 2.5 parts by mass or less, 2.3 parts by mass or less, 2.1 parts by mass or less, 2.0 parts by mass or less, 1.8 parts by mass or less, 1.6 parts by mass or less, or 1.5 parts by mass or less, per 100 parts by mass of the fat or oil, from the viewpoint of improving industrial productivity such as filterability and yield.

From the same viewpoint, the amount of zeolite used is preferably 0.1 part by mass or more, more preferably 0.3 part by mass or more, and still more preferably 0.5 part by mass or more, 0.75 part by mass or more, 0.8 part by mass or more, 0.9 part by mass or more, or 1.0 part by mass or more, per 100 parts by mass of the fat or oil. The upper limit of the amount of zeolite used is not particularly limited, but is preferably 3.5 parts by mass or less, more preferably 2.5 parts by mass or less, and still more preferably 2.2 parts by mass or less, 2.0 parts by mass or less, 1.8 parts by mass or less, 1.6 parts by mass or less, or 1.5 parts by mass or less, relative to 100 parts by mass of the fat or oil. Therefore, in a preferred embodiment, 0.1 to 3.5 parts by mass of zeolite is used per 100 parts by mass of the oil or fat in the contact treatment.

In the case where the contact treatment is performed by the method (3) or (4), the total amount of clay and zeolite used is preferably 0.3 parts by mass or more, more preferably 0.5 parts by mass or more, further preferably 0.75 parts by mass or more, 0.8 parts by mass or more, 1.0 parts by mass or more, 1.2 parts by mass or more, 1.4 parts by mass or more, or 1.5 parts by mass or more, per 100 parts by mass of the fat or oil, from the viewpoint of sufficiently reducing MCPD and glycidol. By the production method of the present invention including the contact treatment of bringing clay and zeolite into contact with the oil or fat, MCPD and glycidol can be sufficiently reduced even if the total amount of clay and zeolite used for the oil or fat is set to be low. For example, the total amount of clay and zeolite used may be 8 parts by mass or less, 7.5 parts by mass or less, or less than 7.5 parts by mass, or the like, preferably 5.0 parts by mass or less than 5.0 parts by mass, more preferably 4.5 parts by mass or less, and still more preferably 4.0 parts by mass or less, 3.5 parts by mass or less, 3.0 parts by mass or less, or 2.5 parts by mass or less, based on 100 parts by mass of the fat or oil. The production method of the present invention including the contact treatment of bringing clay and zeolite into contact with oil and fat can sufficiently reduce MCPD and glycidol even when the total amount of clay and zeolite used is set to be low as described above, and can achieve a particularly excellent effect of achieving both industrial productivity such as filterability and yield and sufficient reduction in MCPD and glycidol.

In the case where the contact treatment is performed by the method (3) or (4), the amount ratio of the clay to the zeolite used in the contact treatment is preferably 0.1 part by mass or more, more preferably 0.3 part by mass or more, further preferably 0.5 part by mass or more, and 0.6 part by mass or more, or 0.7 part by mass or more, relative to 1 part by mass of the clay, from the viewpoint of further improving the efficiency of reduction of MCPDs and glycidols while maintaining the productivity. The upper limit of the amount ratio is preferably 2.5 parts by mass or less, more preferably 2.2 parts by mass or less, and further preferably 2.0 parts by mass or less, 1.8 parts by mass or less, 1.6 parts by mass or less, 1.4 parts by mass or less, 1.2 parts by mass or less, or 1.0 part by mass or less of zeolite with respect to 1 part by mass of clay. In particular, the present inventors have confirmed that: when the amount of zeolite is in the range of 0.5 to 1.2 parts by mass relative to 1 part by mass of clay, the efficiency of decrease of MCPD and glycidyl compounds tends to be particularly excellent.

Temperature of grease in contact treatment

From the viewpoint of efficiently reducing the contents of MCPD and glycidyl compounds, the temperature of the fat or oil in the contact treatment is preferably 50 ℃ or higher, more preferably 60 ℃ or higher, and still more preferably 70 ℃ or higher or 80 ℃ or higher. The upper limit of the temperature of the fat or oil in the contact treatment is, for example, 280 ℃ or less, preferably 260 ℃ or less. Therefore, in a preferred embodiment, the temperature of the fat in the contact treatment is 50 to 260 ℃.

In particular, when clay and zeolite are brought into contact with each other, the temperature of the fat or oil in the contact treatment with clay is preferably 80 ℃ or higher, 90 ℃ or higher, or 100 ℃ or higher, and the upper limit thereof is preferably 150 ℃ or lower, 140 ℃ or lower, 130 ℃ or lower, or 120 ℃ or lower.

In particular, when clay and zeolite are brought into contact with each other, the temperature of the fat or oil in the contact treatment with zeolite is preferably 180 ℃ or higher, more preferably 200 ℃ or higher, and the upper limit thereof is preferably 270 ℃ or lower or 260 ℃ or lower.

In the case of performing the contact treatment of bringing clay and zeolite into contact with the oil or fat at the same time as in the method (3) or (4), the temperature of the oil or fat during the contact treatment is preferably 50 ℃ or higher, more preferably 60 ℃ or higher, and still more preferably 70 ℃ or higher or 80 ℃ or higher, from the viewpoint of efficiently reducing the contents of MCPD and glycidyl compounds. The upper limit of the temperature is preferably 180 ℃ or less, more preferably 160 ℃ or less, further preferably 150 ℃ or less, 140 ℃ or less, or 130 ℃. In particular, the present inventors have confirmed that: when the temperature of the fat during the contact treatment is in the range of 80 to 150 ℃, the fat tends to have an excellent effect of reducing MCPD and glycidyl, and to have a low acid value and peroxide value, a clear color tone, and a good flavor.

As described above, in the method for producing a purified oil or fat of the present invention, when clay and zeolite are brought into contact with each other, the temperature of the oil or fat is high in the contact treatment in which the zeolite is brought into contact with the oil or fat, and is low in the case where the clay and zeolite are brought into contact with each other. That is, depending on the method of the contact treatment, the temperature range of the oil or fat preferred for the contact treatment tends to be different.

Although the reason is not clear, the present inventors speculate that the reason is: the mechanism of reducing the MCPD and the glycidyl is different between the case of separate contact and the case of simultaneous contact.

Pressure in the contact treatment

In the present invention, the clay and the zeolite may be contacted with each other separately or simultaneously, either under reduced pressure or under normal pressure, but from the viewpoint of suppressing oxidation of the fat or oil during the treatment, the contact treatment is preferably carried out under reduced pressure.

When the contact treatment is performed under reduced pressure, the contact treatment is preferably 1.0 × 10⁴Pa or less, more preferably 1.0X 10³Pa or less, more preferably 8.0X 10²Pa or less, particularly preferably 5.0X 10²A reduced pressure condition of Pa or less.

Contact treatment time (contact time) -

From the viewpoint of efficiently reducing the contents of MCPD and glycidyl compounds, when clay and zeolite are brought into contact with each other, the contact time between the oil and the clay is preferably 5 minutes or longer, and more preferably 10 minutes or longer or 15 minutes or longer. From the viewpoint of industrial productivity, the upper limit of the contact time is preferably 60 minutes or less.

From the same viewpoint, when clay and zeolite are brought into contact with each other, the contact time between the oil and fat and zeolite is preferably 5 minutes or longer, more preferably 10 minutes or longer or 15 minutes or longer, and the upper limit of the contact time is preferably 120 minutes or shorter, more preferably 90 minutes or shorter.

In the case of performing the contact treatment of bringing clay and zeolite into contact with the oil and fat at the same time as in the method (3) or (4), the contact time is preferably 5 minutes or longer, more preferably 10 minutes or longer, and still more preferably 15 minutes or longer, from the viewpoint of efficiently reducing MCPD and glycidol. The upper limit of the contact time is not particularly limited, but is, for example, 180 minutes or less, preferably 150 minutes or less, 120 minutes or less, 90 minutes or less, or 60 minutes or less, from the viewpoint of industrial productivity. When the clay and zeolite are brought into contact with the oil or fat at the same time, the oil or fat having a low acid value and peroxide value, a clear color tone, and a good flavor can be obtained while having an excellent effect of reducing MCPD and glycidyl compounds regardless of the contact time. In particular, the present inventors confirmed that: when the contact time is 50 minutes or less (more preferably 40 minutes or less), the oil or fat which has a low acid value and peroxide value, a clear color tone, and a good flavor can be obtained while having a particularly excellent effect of reducing MCPD and glycidyl compounds.

When one or both of clay and zeolite is brought into contact with the fat or oil heated to a predetermined temperature, the starting point of the contact time is set as the contact time. Therefore, in the case of the batch-type contact treatment, the starting point of the contact time is when one or both of clay and zeolite are put into the fat heated to a predetermined temperature.

In addition, when the oil or fat is heated to a predetermined temperature after one or both of clay and zeolite are added to the oil or fat, the starting point is when the oil or fat reaches the predetermined temperature.

In addition, when the end point of the contact treatment is defined as a point at which a predetermined contact time has elapsed from the start point, and when a step other than the contact treatment is performed after the end point is reached, it is preferable to filter clay and zeolite from the fat or oil by a conventional method.

Number of contact treatments-

In the present invention, the contact treatment may be performed a plurality of times. From the viewpoint of industrial productivity and the viewpoint of cost performance reduction of MCPD and glycidyl oils, the contact treatment is preferably performed 2 times or less, more preferably 1 time. In the case where the contact treatment is performed a plurality of times, the conditions of the respective treatments may be the same or different.

In the case of performing the contact treatment a plurality of times, (1) the clay and zeolite may be filtered out in each contact treatment and then the contact treatment may be performed after newly adding the clay and zeolite, and (2) the next contact treatment may be performed without filtering out in each contact treatment, and preferably, the clay and zeolite are filtered out in each contact treatment and then the contact treatment is performed after newly adding the clay and zeolite.

Other additives

In the present invention, in the contact treatment, an optional additive may be added in addition to the clay and the zeolite. Examples of the additive used in the contact treatment in the present invention include an adsorbent such as silica gel, and a pH adjuster such as citric acid.

The additive used in the contact treatment may be added in an arbitrary amount, but is preferably contained in an amount of 0.1 to 1.5 parts by mass per 100 parts by mass of the fat or oil, from the viewpoint of obtaining a fat or oil with a good flavor and efficiently reducing MCPD and glycidol.

When the contact treatment is performed by adding a pH adjuster such as citric acid to the fat or oil as an aqueous solution, the pH adjuster is added so that the amount of pure components added per 100 parts by mass of the fat or oil falls within the above range.

< other treatment >

The method for producing a purified oil or fat of the present invention may further comprise, in addition to the contact treatment: other processes (steps) provided in conventional methods for producing fats and oils.

Examples of other treatments include: degumming for removing phospholipids, deoxidation for removing free fatty acids, dewaxing, decolorizing, and deodorizing. These treatments may be carried out by conventional methods. The conditions and the order of these treatments are not particularly limited, and the treatment may be carried out under the conditions and the order usually set in the production of fats and oils (for example, refer to the base and application of fats and oils, published by the japan oil chemical society, P215-219, 1 st edition, 4 months and 1 st day, 17 years).

In the method for producing a purified fat or oil of the present invention, it is preferable to perform deodorization treatment on the fat or oil at least 1 time in addition to the above-mentioned contact treatment, from the viewpoint of obtaining a fat or oil in which the amount of MCPD and glycidyl is sufficiently reduced.

The contact treatment and the deodorization treatment are preferably performed alternately, and either of the contact treatment and the deodorization treatment may be performed first, but from the viewpoint of reducing effects of MCPD and glycidyl, and from the viewpoint of obtaining a fat or oil with good flavor, it is preferable to perform the deodorization treatment after performing the contact treatment. Accordingly, in one preferred embodiment, the method for producing a purified oil or fat of the present invention further comprises: the contact-treated fat or oil is subjected to deodorization treatment for deodorization.

In the present invention, the deodorization treatment can be carried out by a conventional method, and the conditions of the deodorization treatment are not particularly limited. Hereinafter, as an example of the specific deodorization treatment, a deodorization treatment by reduced pressure steam distillation in which steam and fat are brought into contact under reduced pressure will be described.

The lower limit of the fat temperature when the steam is brought into contact with the fat is preferably 180 ℃ or higher, more preferably 200 ℃ or higher, further preferably 210 ℃ or higher, and most preferably 220 ℃ or higher, from the viewpoint of sufficiently reducing the contents of MCPD and glycidyl compounds and obtaining a fat having a good flavor. The upper limit of the fat temperature when the steam is brought into contact with the fat is preferably 270 ℃ or lower, more preferably 260 ℃ or lower, and most preferably 250 ℃ or lower, from the viewpoint of suppressing an increase in acid value, peroxide value, or the like and preventing deterioration in the production of the fat. Therefore, in a preferred embodiment, the temperature of the fat or oil in the deodorization treatment is 180 to 270 ℃.

The lower limit of the contact time when the water vapor is brought into contact with the fat or oil is preferably 30 minutes or longer, more preferably 45 minutes or longer, and most preferably 60 minutes or longer, and the upper limit of the contact time when the water vapor is brought into contact with the fat or oil is preferably 180 minutes or shorter, more preferably 150 minutes or shorter, and most preferably 120 minutes or shorter.

The deodorization treatment is carried out on the mixture,from the viewpoint of suppressing oxidation in the treatment and efficiently removing low boiling point components, it is preferably 8.0 × 10²Pa or less, more preferably 5.0X 10²Under reduced pressure of Pa or less. The amount of steam to be blown is preferably 1% by mass or more, more preferably 1.5% by mass or more, and the upper limit thereof is preferably 5% by mass or less, more preferably 4% by mass or less, when the amount of the steam is applied to the fat (that is, when the mass of the fat is 100% by mass).

In the case where the deodorization treatment is performed plural times, the conditions of the respective treatments may be different or the same.

The deodorization treatment is preferably performed 2 or more times when the crude oil is used as a raw material, and preferably 1 or more times when RBD fat or NBD fat, which will be described later, is used.

In conventional methods for producing purified oils and fats, oils and fats having good flavor can be obtained by deodorization treatment, but there is a problem that MCPDs and glycidols in oils and fats increase. In contrast, according to the method for producing a purified oil or fat of the present invention, even if the purified oil or fat is subjected to deodorization treatment, the obtained purified oil or fat has a low content of MCPD and glycidyl compounds and a good flavor.

The reason why the content of MCPD and glycidol in the purified oil and fat obtained by the deodorization treatment is small is not clear at this stage, but it is presumed that: the starting materials necessary for the production of MCPD-like, glycidol-like materials are reduced by some mechanism.

In general, in the production of fats and oils, a decoloring treatment for removing coloring matter or the like is performed before a deodorization treatment.

In the method for producing a purified oil or fat of the present invention, the above-mentioned contact treatment may be performed as a decoloring treatment. The contact treatment may be performed independently of the decoloring treatment.

In the case where the contact treatment and the decoloring treatment are separately performed, the decoloring treatment may be performed before the contact treatment, between the contact treatment and the deodorization treatment. Specifically, for example, in the case of using the RBD fat or oil as a raw material, the RBD fat or oil may be subjected to a decoloring treatment, followed by the contact treatment and then a deodorizing treatment. Further, the RBD fat or oil may be subjected to the above-mentioned contact treatment, followed by a decolorization treatment and then a deodorization treatment.

In the present invention, in the case where the contact treatment and the decoloring treatment are separately performed, the decoloring treatment may be performed by a conventional method. The conditions of the decoloring treatment are not particularly limited, and the decoloring treatment may be performed under the same conditions as those of the decoloring treatment usually set in the method for producing a fat or oil.

As a specific decoloring treatment, for example, a decoloring material represented by clay is preferably added to the fat or oil supplied to the decoloring treatment in an amount of about 0.1 to 2% by mass, and more preferably 1.0X 10⁴The heating is preferably carried out under reduced pressure of Pa or less at 80 to 150 ℃ while stirring the fat or oil. The heating time is preferably 5 to 60 minutes. After heating the fat, the clay was filtered out from the fat to obtain a decolorized fat.

In the case where the decoloring treatment is performed a plurality of times, the conditions of each treatment may be different or the same.

The decoloring treatment is preferably performed 2 or more times when the crude oil is used as a raw material, and preferably 1 or more times when an RBD fat or NBD fat, which will be described later, is used.

Raw material grease-

The method for producing a purified oil or fat of the present invention can be applied to edible oils or fats without particular limitation.

Examples of the edible oil and fat include: palm oil, palm kernel oil, coconut oil, corn oil, olive oil, cottonseed oil, soybean oil, rapeseed oil, rice oil, sunflower oil, Safflower oil (saflower oil), cocoa butter, shea butter, mango kernel oil, monkey fat, horse fat and other vegetable oils and fats, beef tallow, milk fat, lard, fish oil, whale oil and other animal oils and fats, and processed oils and fats obtained by subjecting these oils and fats to 1 or more treatments selected from hydrogenation, fractionation and transesterification. The present invention is applicable to an edible oil or fat selected from these alone or an edible oil or fat obtained by combining and mixing 2 or more kinds of these.

The method for producing a purified oil or fat of the present invention can be applied to crude oil, and can also be applied to an already purified oil or fat. It is known that MCPD and glycidol are generated at a high temperature in the production process of a fat and oil, and the method for producing a purified fat and oil of the present invention is preferably applied to a fat and oil which has undergone a deodorization step of performing steam distillation at a high temperature 1 or more times. Therefore, in a preferred embodiment, the method for producing a purified oil or fat of the present invention is performed on an oil or fat that has undergone the deodorization step 1 or more times. The deodorization step may be performed under the same steps and conditions as the above-described deodorization treatment. In particular, it is preferable to select RBD oils and fats in which crude oil is primarily purified by physical refining and NBD oils and fats in which crude oil is primarily purified by chemical refining.

The method for producing a purified fat or oil of the present invention is preferably applied to a palm-based fat or oil, from the viewpoint of its particularly remarkable effect. The palm-based fat or oil in the present invention refers to palm oil, palm kernel oil, and fat or oil obtained by subjecting palm oil or palm kernel oil to at least 1 kind of physical or chemical treatment selected from hydrogenation, fractionation, transesterification, and the like. When any palm-based fat or oil is selected, a fat or oil having an extremely low content of MCPD and glycidyl can be produced by the method of the present invention.

Characteristics of the grease obtained by the manufacturing method of the present invention-

The fat or oil obtained by the production method of the present invention has a feature of having an extremely low content of MCPD and glycidyl compounds.

For example, although the RBD palm-based fat or oil contains MCPD compounds in an amount of more than 4ppm and glycidol compounds in an amount of more than 3ppm, the total content of MCPD compounds in the fat or oil obtained by applying the production method of the present invention is preferably 4ppm or less, more preferably 0 to 3ppm, and the total content of glycidol compounds in the fat or oil obtained is preferably 3ppm or less, more preferably 0 to 2.5ppm, although the content varies depending on the grade specified by DOBI and the like.

As a method for quantifying the content of MCPD and glycidyl in oils and fats, a direct analysis method and an indirect analysis method are known from the principle difference. In the present invention, the quantitative determination can be carried out by any method, but from the viewpoint of a small number of types of standard substances to be used and economy, it is preferable to carry out the quantitative determination of MCPDs and glycidols by an indirect analysis method. For example, as a simple indirect analysis method, the method described in Japanese patent No. 5864278, OLESCIENCE volume 17, No. 4 (2017) p171-178, and the like can be used. The method comprises the following steps: a method in which a fatty acid ester of 3-MCPD, a fatty acid ester of 2-MCPD, and a fatty acid glycidyl ester in an oil or fat are hydrolyzed and converted into free components, and the free components are derivatized with phenylboronic acid and then measured by GC-MS. The measurement conditions by GC-MS can be arbitrarily set with reference to the above-mentioned documents, and for example, the measurement can be performed under the following conditions.

< gas chromatography section >

Column: VF-5ms

Injection amount: 1uL

Injection method: not divided into

Injection port temperature: 250 deg.C

The carrier gas: helium, 1.2 mL/min

Column oven: 60 ℃ below zero: 1 minute → 60 to 150 ℃: 10 ℃/min, 150-180 ℃: 3 ℃/min, 180-300 ℃: 30 ℃/min, 300 ℃: 8 minutes for a total of 32 minutes

< quality analysis section >

The transfer line: 280 deg.C

Ion source temperature: 230 deg.C

Quadrupole temperature: 150 ℃ C

Ionization method: EI, positive ion

In the fat or oil obtained by the production method of the present invention, the acid value is preferably 0.5 or less, and more preferably 0.3 or less, from the viewpoint of obtaining a fat or oil having a good flavor. The acid value of the oil or fat can be measured, for example, by the method shown in standard oil or fat analysis test method (2013 version) 2.3.1 to 2013, which is established by the Japan oil chemical society.

In the fat or oil obtained by the production method of the present invention, the peroxide value is preferably 0.3 or less, more preferably 0.1 or less, from the viewpoint of obtaining a fat or oil having a good flavor. The peroxide value of an oil or fat can be measured, for example, by a method shown in standard oil or fat analysis test method (2013 version) 2.5.2 established by the japan oil chemical society.

Food using the purified oil obtained by the production method of the present invention-

The fat or oil obtained by the production method of the present invention can be used for the production of beverages and foods, similarly to general fats or oils. The beverage and food using the fat or oil obtained by the production method of the present invention are characterized in that the contents of MCPD and glycidyl are suppressed to be low as compared with the beverage and food using conventional fat or oil.

Examples of the beverage and food include: margarine, shortening, spread, dressing, mayonnaise, frozen confectionery, fat and oil for spray coating, fat and oil for deep frying, fat and oil for chocolate, fat and oil for batter, fat and oil for powder, confectionery dough for stuffing, western confectionery, japanese confectionery, bread, snack, curry, stew, baked food, seasoning, instant cooked food, processed livestock product, processed aquatic product, processed vegetable product, and the like, and can be used as a material for producing drinks and foods such as milk powder for infant care and the like which are required to reduce the level of MCPD and glycidyl oils.

[ method of reducing MCPD or glycidyl Compounds in oils and fats ]

The present invention also provides a method for reducing MCPD or glycidyl compounds in fats and oils (hereinafter, also simply referred to as "the method for reducing of the present invention"). The reduction method of the present invention comprises: and (3) contact treatment of contacting the oil and fat with clay and zeolite.

In the contact treatment, it is preferable to contact the fat or oil with clay and zeolite simultaneously from the viewpoint of efficiently reducing MCPD and glycidyl compounds in the fat or oil and from the viewpoint of producing a fat or oil excellent in flavor and color tone. The conditions for contacting the clay and zeolite with the fat and oil are as described above.

As the clay, activated clay is preferably used, and as the zeolite, 1 or more selected from natural zeolite and synthetic zeolite is preferably used. The preferable composition, amount and the like of clay and zeolite are as described above.

In the reducing method of the present invention, it is preferable to perform a deodorization treatment after the contact treatment, from the viewpoint of enhancing the effect of reducing MCPD and glycidyl compounds. The conditions of the deodorization treatment are as described above.

[ decolorizing agent for oils and fats and reducing agent for MCPD or glycidyl oils in oils and fats ]

The present invention also provides a decolorizer for fats and oils, and a reducing agent for MCPD or glycidyl compounds in fats and oils. The decolorizer for fats and oils and the reducer for MCPD or glycidyl compounds in fats and oils according to the present invention contain clay and zeolite, and are used in contact with fats and oils during the production of fats and oils.

As the clay, activated clay is preferably used, and as the zeolite, 1 or more selected from natural zeolite and synthetic zeolite is preferably used. The preferred composition, mixing amount, and the like of the clay and zeolite are as described above. In a preferred embodiment, the fat-and-oil decolorizer of the present invention contains 0.1 to 2.5 parts by mass of zeolite per 1 part by mass of clay. The fat-and-oil decolorizer of the present invention may be a 1-agent type decolorizer obtained by mixing clay and zeolite, or a 2-agent type decolorizer obtained by combining a 1 st agent containing clay and a 2 nd agent containing zeolite. In one preferred embodiment, the MCPD-based or glycidyl-based reducing agent in the fat or oil of the present invention contains 0.1 to 2.5 parts by mass of zeolite per 1 part by mass of clay. The MCPD-or glycidyl-based reducing agent in the fat or oil of the present invention may be a 1-agent type reducing agent obtained by mixing clay and zeolite, or a 2-agent type reducing agent obtained by combining a 1 st agent containing clay and a 2 nd agent containing zeolite.

The decolorizer for fats and oils and the reducer for MCPD or glycidyl compounds in fats and oils according to the present invention may contain any additive other than clay and zeolite. Examples of such additives include an adsorbent such as silica gel, and a pH adjuster such as citric acid. The content of the additive is not particularly limited as long as the effect of the present invention is not impaired, and the amount to be mixed in the fat or oil and the like can be determined in the above-described manner. When such an additive is contained, the decolorizer for fats and oils and the MCPD-based or glycidyl-based reducing agent in fats and oils of the present invention may be a 1-agent type agent in which clay, zeolite and the additive are mixed, a 3-agent type agent in which a 1 st agent containing clay, a 2 nd agent containing zeolite and a 3 rd agent containing the additive are combined, or a 2-agent type agent in which a 1 st agent containing 2 or more components selected from clay, zeolite and the additive and a 2 nd agent containing the remaining components are combined.

In addition, in the use of the decolorizer for fats and oils and the reducer for MCPDs or glycidol in fats and oils of the present invention, it is preferable to perform a contact treatment of bringing the decolorizer for fats and oils or the reducer for MCPDs or glycidol in fats and oils of the present invention into contact with fats and oils and then perform a deodorization treatment of fats and oils, from the viewpoint of improving the effect of reducing MCPDs or glycidol. The conditions of the contact treatment and the deodorization treatment are as described above.

Examples

The present invention will be described in detail below based on examples. However, the present invention is not limited to the embodiments shown below. If not otherwise specified, RBD palm oil is used as the starting oil. For the RBD palm oil used, it is as follows. In addition, if not specifically stated, the following are used as the clay and zeolite. Further, if not specifically stated, the deodorization treatment is performed under the conditions shown below.

< used RBD palm oil >

In the following discussions 1 to 9, RBD palm oil (manufactured by AAA, MCPD content 4.32ppm, and glycidyl group 3.69ppm) obtained by physically refining palm crude oil was used as a raw material, except for the specific case.

< Clay and Zeolite used >

Clay: activated clay (product name "Galleon EARTH V2R", manufactured by Shuizzichemistry industries Co., Ltd.)

Acid clay: acid clay (product name "MIZUKA ACE # 300", manufactured by Shuizui chemical industry Co., Ltd.)

Zeolite: natural zeolite (product name "SGW", manufactured by ZEEKLITE corporation, average particle diameter 10 μm, structure of clinoptilolite structure and mordenite structure coexisting)

< deodorization treatment >

As the deodorization treatment, deodorization treatment by steam distillation was performed. In the following discussions 1 to 9, the dissolved oil is specifically 5.0X 10²Steam distillation was carried out at 230 ℃ for 90 minutes under reduced pressure of Pa or lower. The amount of steam blown was 3 mass%/h based on the amount of the fat or oil.

[ measurement and evaluation methods ]

The measurement and evaluation method will be described below.

< measurement of the content of MCPD and glycidyl oils in fats & oils >

The contents of MCPD and glycidyl compounds contained in the fat and oil were measured by the following procedure using an indirect analysis method.

The purified oils and fats obtained in examples and comparative examples were hydrolyzed according to the method described in [ example ] of japanese patent No. 5864278, and the fatty acid esters of 3-MCPD, 2-MCPD and glycidol in the oils and fats were converted into free components of 3-MCPD, 2-MCPD and glycidol, respectively, which were derivatized with phenylboronic acid and then quantified by GC-MS. The content of MCPD-like substances in RBD palm oil used for screening was also quantified by the same method. The conditions in the Gas Chromatography (GC) section and the Mass Spectrometer (MS) section are as follows.

Gas chromatography section-

Column: VF-5ms

Injection amount: 1uL

Injection method: without diversion

Injection port temperature: 250 deg.C

The carrier gas: helium, 1.2 mL/min

Column oven: 60 ℃ of: 1 minute → 60 to 150 ℃: 10 ℃/min, 150-180 ℃: 3 ℃/min, 180-300 ℃: 30 ℃/min, 300 ℃: 8 minutes for a total of 32 minutes

Mass analysis section-

The transfer line: 280 deg.C

Ion source temperature: 230 deg.C

Quadrupole temperature: 150 ℃ C

Ionization method: EI, positive ion

The "sum of MCPD species" in the tables shown below means the sum of the contents of MCPD species contained in the oils and fats, in units of mass ppm. Similarly, "the sum of glycidyl oils" means the sum of the content of glycidyl oils contained in the fat and oil, and the unit is ppm by mass. In the tables shown below, "reduction rate of MCPD and" reduction rate of glycidyl oil "indicate how much MCPD and glycidyl oil can be reduced by the contact treatment based on the total amount of MCPD and glycidyl oil in the RBD palm oil before the treatment, and are calculated according to the following formulas. When the reduction rate of MCPD and glycidyl is a negative value, the increase in the content of MCPD and glycidyl after the treatment is based on the sum of MCPD and glycidyl in RBD palm oil before the treatment.

The reduction rate (percentage) of MCPD class is [ (content of MCPD class before treatment-content of MCPD class after treatment)/(content of MCPD class before treatment) ] × 100

The reduction rate (percentage) of glycidyl compounds was [ (content of glycidyl compounds before treatment-content of glycidyl compounds after treatment)/(content of glycidyl compounds before treatment) ] × 100

The fats and oils having a MCPD reduction rate of 10% or more and a glycidyl oil reduction rate of 40% or more were treated as non-defective products.

< measurement of acid value and peroxide value >

The Acid Value (AV) of the oil or fat was measured according to the method shown in Standard oil and fat analytical test method (2013 version) 2.3.1-2013, which was established by the Japan oil chemical society. The peroxide value (POV) of the oil or fat was measured according to a method shown in standard oil or fat analysis test method (2013 version) 2.5.2, which was established by the japan oil chemical society.

< evaluation of color tone of fat >

Color tone of oil and fat the R value and the Y value were measured according to the Lovibond (Lovibond) method shown in the Japanese oil chemical society, Standard oil and fat analysis test method (1996 edition) 2.2.1.1-1996. In the tables shown below, the values of R/Y are shown.

< evaluation of flavor of fat & oil >

On the day of manufacture, 2g of the oil and fat adjusted to 60 ℃ was measured with a small spoon and directly put into the mouth, and whether or not the odor of the oil and fat was perceived was evaluated by the panelists 12 according to the evaluation criteria shown below, and the average of the evaluation results is shown in the table. In the flavor evaluation, the sensory degree of the panelists was adjusted in advance.

Evaluation criteria:

10, point: has no odor even if it is contained in the mouth

And 9, point: the peculiar smell is sensed after 2 to 3 seconds in the mouth

And 8, point: the peculiar smell is sensed just after the tea is put into the mouth

< discussion 1: effect on contact treatment >

In the study 1, a conventional general method for producing fats and oils is compared with the method for producing fats and oils of the present invention including a contact treatment of bringing clay into contact with zeolite.

Reference example 1-1

Heating RBD palm oil to 85 deg.C, adding 2 wt% of white clay based on the weight of oil and fat, and adjusting the content to 1.0 × 10³Under a reduced pressure of Pa or less, the fat and oil were stirred for 45 minutes while keeping the temperature of the fat and oil at 85 ℃ to thereby carry out a decoloring treatment. Then, a deodorization treatment is performed under the above conditions to obtain a purified oil.

(example 1-1)

In this example, clay and zeolite were brought into contact with the oil and fat, respectively.

First, for RB which is heated and dissolvedD palm oil, contacting it with zeolite. Specifically, the RBD palm oil dissolved therein was adjusted to 250 ℃ at 1.0X 10 by adding 1.5 mass% of zeolite and then adjusting the temperature of the oil or fat³Stirring was carried out under reduced pressure of Pa or less for 30 minutes. After the contact treatment with the zeolite, the zeolite is filtered off.

Next, 2 mass% of clay was added to the RBD palm oil that was in contact with zeolite. Heating the mixture so that the temperature of the fat is 85 ℃ at 1.0X 10³Stirring was performed under reduced pressure of Pa or less for 45 minutes.

Then, the clay was filtered off, and the obtained oil was subjected to deodorization treatment to obtain a purified oil.

(examples 1 to 2)

In this example, clay and zeolite were simultaneously brought into contact with the oil and fat.

First, 2 mass% of clay and 1.5 mass% of zeolite were weighed out in advance with respect to the weight of fat and oil, and dry-mixed so as to be uniform.

Next, using this mixture, a contact treatment was performed on the RBD palm oil that was heated and dissolved. During the contact treatment, the temperature of the oil is adjusted to 250 ℃ at 1.0X 10³Stirring was carried out under reduced pressure of Pa or less for 30 minutes. After the contact treatment, the clay and zeolite are filtered off.

Then, the RBD palm oil subjected to the contact treatment was subjected to deodorization treatment to obtain a purified oil.

Hereinafter, the purified oil and fat obtained in reference example 1-1 is referred to as REx1-1, and the purified oils and fats obtained in examples 1-1 to 1-2 are referred to as Ex1-1 to 1-2, and the numbers thereof correspond to the numbers of the examples and reference examples. The following reference examples and examples may be similarly described.

The obtained Ex1-1 to 1-2 and REx1-1 were each shown in table 1 for the MCPD content, the glycidol content, the reduction rate of RBD palm oil-derived oil, the Acid Value (AV), the peroxide value (POV), the color and the flavor.

[ Table 1]

As is clear from the results of examination 1, the method for producing a purified oil or fat of the present invention, which comprises a contact treatment in which clay and zeolite are brought into contact with each other, surprisingly reduces the content of MCPDs in the oil or fat to 4pp m or less and reduces the content of glycidyl compounds to 3ppm or less. It was confirmed that the content of MCPD compounds and glycidyl compounds in the fat and oil can be highly reduced when compared with the production method of reference example 1-1.

In addition, when the methods for producing fats and oils of examples 1-1 and 1-2 were compared, it was confirmed that the effect of reducing MCPD and glycidyl oils tends to be higher in the case where clay and zeolite were simultaneously brought into contact than in the case where clay and zeolite were separately brought into contact.

< discussion 2: regarding the temperature of the oil and fat in the contact treatment >

In the study 2, an appropriate range of the oil temperature in the contact treatment of bringing clay into contact with zeolite is studied.

(example 2-1)

Purified oils and fats were obtained in the same manner as in example 1-2, except that the temperature of oils and fats in the contact treatment was adjusted to 120 ℃.

(example 2-2)

Purified oils and fats were obtained in the same manner as in example 1-2 except that the temperature of oils and fats in the contact treatment was adjusted to 90 ℃.

(examples 2 to 3)

Purified oils and fats were obtained in the same manner as in example 1-2, except that the temperature of oils and fats in the contact treatment was adjusted to 60 ℃.

The obtained Ex2-1 to 2-3 contained MCPD content, glycidol content, and the reduction rate, acid value, peroxide value, color tone, and flavor derived from RBD palm oil, which were shown in table 2.

Table 2

From the results of study 2, it was confirmed that the method for producing a purified oil and fat of the present invention, which comprises a contact treatment of bringing clay into contact with zeolite, can achieve an effect of reducing MCPD and glycidyl oils in a wide range of oil and fat temperatures in the contact treatment of 60 to 250 ℃. In addition, it was confirmed that the temperature of the fat and oil during the contact treatment tends to affect the effect of reducing MCPD and glycidyl oils, and the acid value, peroxide value, color tone, and flavor of the finally obtained purified fat and oil. The higher the temperature of the fat or oil in the contact treatment, the higher the effect of reducing MCPD and glycidyl oils tends to be. On the other hand, when the temperature of the oil or fat in the contact treatment is low, the oil or fat having a low acid value and a low peroxide value tends to be obtained while achieving the effect of reducing MCPD and glycidyl compounds. In particular, when the temperature of the oil or fat in the contact treatment is in the range of 80 to 150 ℃ such as 90 ℃ and 120 ℃, the oil or fat tends to have an excellent effect of reducing MCPD and glycidyl compounds, a low acid value and peroxide value, a clear color tone, and a good flavor.

< discussion 3: for contact treatment time >

In the study 3, a suitable range of the contact treatment time for contacting the clay and the zeolite was studied.

(example 3-1)

Purified oils and fats were obtained in the same manner as in example 2-2, except that the contact treatment time was changed to 60 minutes.

(example 3-2)

Purified oils and fats were obtained in the same manner as in example 2-2, except that the contact treatment time was 180 minutes.

The obtained Ex3-1 and Ex3-2 were each shown in table 3 for the MCPD content, the glycidol content, and the reduction rate, acid value, peroxide value, color tone, and flavor of RBD palm oil-derived products thereof.

Table 3

From the results of investigation 3, it was confirmed that the method for producing a purified oil or fat of the present invention, which comprises the contact treatment of bringing clay into contact with zeolite, can achieve the effect of reducing MCPD and glycidyl compounds in a wide range of contact treatment time of 30 to 180 minutes. Further, it was confirmed that an oil or fat having a low acid value and peroxide value, a clear color tone and a good flavor was obtained regardless of the contact treatment time. In particular, from the viewpoint of the effect of reducing MCPD and glycidyl compounds, it has been found that it is preferable to shorten the contact treatment time.

< discussion 4: for pressure conditions in the contact treatment >

In the study of fig. 4, an appropriate range of pressure conditions in the contact treatment of bringing clay into contact with zeolite was studied.

(example 4-1)

Purified oils and fats were obtained by the same procedures as in example 2-2 except that the contact treatment was carried out under normal pressure.

The obtained Ex4-1 was shown in table 4 for the MCPD content, the glycidol content, and the reduction rate, acid value, peroxide value, color tone, and flavor of RBD-derived palm oil.

"Table 4

From the results of investigation 4, it was confirmed that by the method for producing a purified oil or fat of the present invention including the contact treatment of bringing clay and zeolite into contact with each other, the effect of reducing MCPD and glycidyl oils can be achieved and an oil or fat having a low acid value and peroxide value, a clear color tone, and a good flavor can be obtained by performing the contact treatment under either of a reduced pressure and a normal pressure. In particular, from the viewpoint of the effect of reducing MCPD and glycidyl, it has been found that the contact treatment is preferably performed under reduced pressure.

< discussion 5: amount of clay and zeolite used >

In the study 5, suitable ranges of the respective amounts of clay and zeolite used in the contact treatment were studied.

(example 5-1)

Purified oils and fats were obtained by the same treatment as in example 2-2, except that the amount of clay and the amount of zeolite used in the contact treatment were 1% by mass and 0.75% by mass, respectively, based on the oils and fats. The amount ratio of clay to zeolite was 0.75 parts by mass relative to 1 part by mass of clay.

(example 5-2)

Purified oils and fats were obtained by the same treatment as in example 2-2, except that the amount of zeolite used in the contact treatment was 0.75% by mass based on the oils and fats. The amount ratio of clay to zeolite was 0.38 parts by mass relative to 1 part by mass of clay.

(examples 5 to 3)

Purified oils and fats were obtained by the same treatment as in example 2-2, except that the amount of clay used in the contact treatment was 1% by mass of oils and fats. The amount ratio of clay to zeolite was 1.5 parts by mass relative to 1 part by mass of clay.

(examples 5 to 4)

Purified oils and fats were obtained by the same treatment as in example 2-2, except that the amount of zeolite used in the contact treatment was 3% by mass of oils and fats. The amount ratio of clay to zeolite was 1.5 parts by mass of zeolite to 1 part by mass of clay.

(examples 5 to 5)

Purified oils and fats were obtained by the same treatment as in example 2-2 except that the amount of clay and the amount of zeolite used in the contact treatment were set to 4% by mass and 3% by mass, respectively, with respect to oils and fats. The amount ratio of clay to zeolite was 0.75 parts by mass relative to 1 part by mass of clay.

The obtained Ex5-1 to Ex5-5 were each shown in table 5 for the MCPD content, the glycidol content, and the reduction rate, acid value, peroxide value, color tone, and flavor of RBD palm oil-derived oil.

As a result of the examination of fig. 5, it was confirmed that, by the method for producing a purified oil and fat of the present invention including the contact treatment of contacting clay and zeolite, even if the amounts of clay and zeolite used in the contact treatment and the amount ratio of the clay and zeolite to oil and fat are changed, the effect of reducing MCPD and glycidyl compounds can be achieved, and an oil and fat having a low acid value and peroxide value, a clear color tone, and a good flavor can be obtained. Specifically, it was confirmed that the desired effect (Ex-5-1) was achieved even under the condition that the total amount of clay and zeolite to the oil and fat was low, i.e., 1.75% by mass. On the other hand, even when the amount of clay or zeolite used for the contact treatment is increased as in Ex5-4 or Ex5-5, the contribution to the effect of reducing MCPD and glycidyl compounds is limited.

In addition, when the amount ratio of clay to zeolite used in the contact treatment is in the range of 0.5 to 1.2 parts by mass of zeolite to 1 part by mass of clay, as in the case of 0.75 parts by mass of zeolite to 1 part by mass of clay, the effect of reducing MCPD and glycidyl compounds tends to be particularly excellent.

< discussion 6: for the kind of zeolite >

In the study 6, the suitable kind of zeolite to be contacted with clay is studied. Further, the effect of the contact treatment with a component other than zeolite was examined.

(example 6-1)

Purified oils and fats were obtained by treating in the same manner as in example 2-2 except that natural zeolite (product name "SGW", manufactured by ZEEKLITE K.K., having an average particle diameter of 10 μm) was used in place of the natural zeolite (product name "SGW-B4", manufactured by ZEEKLITE K.K., having an average particle diameter of 18 μm, and having a clinoptilolite structure and a mordenite structure).

(example 6-2)

Purified oils and fats were obtained by treating in the same manner as in example 2-2 except that calcined zeolite (product name "calcined SGW" (when "SGW" is produced, calcined and cooled before classification to partially ceramize) was used instead of natural zeolite (product name "calcined SGW", manufactured by ZEEKLITE K.K.) and that calcined zeolite (product name "calcined SGW", manufactured by ZEEKLITE K.K., average particle size of 10 μm, structure of clinoptilolite and mordenite) was used.

(examples 6 to 3)

Purified oils and fats were obtained by treating in the same manner as in example 2-2 except that natural zeolite (product name "SP # 600", zeolite having a mordenite structure and an average particle diameter of 1.9 μm, manufactured by Nintendo powdered Industrial Co., Ltd.) was used in place of the natural zeolite (product name "SGW", manufactured by ZEEKLITE K.K.).

(examples 6 to 4)

Purified oils and fats were obtained by treating the oils and fats in the same manner as in example 2-2 except that natural zeolite (product name "SGW", manufactured by ZEEKLITE corporation, having an average particle diameter of 10 μm) was used instead of natural zeolite (product name "IZUKALITE", manufactured by IZUKA, Inc., having a mordenite structure, and having an average particle diameter of 63 μm or less).

(examples 6 to 5)

Purified oils and fats were obtained by treating in the same manner as in example 2-2 except that natural zeolite (product name "SGW", manufactured by ZEEKLITE K.K., having an average particle diameter of not more than 180 μm, manufactured by ZEO K.K.) was used in place of the natural zeolite (product name "SU", manufactured by ZEEKLITE K.K., having an average particle diameter of 10 μm).

Comparative example 6-1

Purified oils and fats were obtained by treating the oils and fats in the same manner as in example 2-2 except that acid clay was used instead of natural zeolite (product name "SGW", manufactured by ZEEKLITE corporation, average particle diameter: 10 μm).

Hereinafter, the purified oil and fat of comparative example 6-1 may be referred to as CEx6-1 and may be referred to by the reference numerals of the comparative examples. In the following comparative examples, the same description may be applied.

The obtained Ex6-1 to Ex6-5 and CEx6-1 were each shown in table 6 for the MCPD content, the glycidol content, and the reduction rate, acid value, peroxide value, color and flavor of RBD palm oil-derived oil.

From the results of investigation 6, it was confirmed that, by the method for producing a purified oil or fat of the present invention including the contact treatment of bringing clay into contact with zeolite, even if the kind of zeolite used in the contact treatment is changed, the effect of reducing MCPD and glycidyl compounds can be achieved, and an oil or fat having a low acid value and peroxide value, a clear color tone, and a good flavor can be obtained. In particular, when a zeolite having an average particle diameter of 15 μm or less, such as a zeolite having an average particle diameter of 10 μm, is used, the effect of reducing MCPD and glycidyl compounds tends to be particularly excellent. In addition, when the unfired zeolite is used, the reduction effect of MCPD and glycidyl compounds tends to be particularly excellent.

In addition, when the structure of the zeolite used is carefully observed, the zeolite having a clinoptilolite structure tends to have a higher effect of reducing MCPD-like compounds than the zeolite having a mordenite structure.

On the other hand, in the test using acid clay instead of zeolite, although the effect of reducing glycidyl was obtained, the effect of reducing MCPD was hardly obtained.

< discussion 7: effect on additives >

In the discussion 7, the effects of the case where various additives were added during the contact treatment were examined.

(example 7-1)

Purified oil and fat was obtained in the same manner as in example 2-2, except that silica gel (product name "sylupite 130", manufactured by FUJI SILYSIA CHEMICAL corporation) was further added to the oil and fat in an amount of 1 mass% in addition to clay and zeolite.

(example 7-2)

Purified fats and oils were obtained in the same manner as in example 2-2 except that 50 mass% citric acid aqueous solution was added so that the added citric acid was purified to be 0.33 mass% with respect to the fats and oils, except that clay and zeolite were used.

The obtained Ex7-1 and Ex7-2 were each shown in table 7 for the MCPD content, the glycidol content, and the reduction rate, acid value, peroxide value, color tone, and flavor of RBD palm oil-derived oil.

"Table 7

From the results of investigation 7, it was confirmed that the method for producing a purified oil and fat of the present invention, which comprises a contact treatment of bringing clay and zeolite into contact with each other, can achieve a reduction effect of MCPD and glycidyl oils and also can obtain an oil and fat having a low acid value and peroxide value, a clear color tone, and a good flavor even when an additive is added during the contact treatment. In this regard, it was confirmed that the effect of reducing MCPD in particular tends to be reduced by the addition of the additive.

< discussion 8: number of times of contact treatment >

In the study 8, the effect of the case where the contact treatment was performed a plurality of times in the process of purifying the oil or fat was studied.

(example 8-1)

A purified oil and fat was obtained in the same manner as in example 2-2, except that the purified oil and fat obtained in example 2-2 was used as a raw material. The purified fat is obtained by subjecting RBD palm oil to two contact treatments with clay and zeolite.

"Table 8")

From the results of the study 8, it was confirmed that the effect of reducing MCPD can be further improved by performing the contact treatment of contacting clay and zeolite a plurality of times. On the other hand, it was confirmed that the effect of reducing glycidyl esters was slightly reduced. This is presumably because the number of treatment steps increases, and the time for heating the purified oil or fat becomes long, so that glycidyl oil is produced again. From these results, although the MCPD can be further reduced by performing the contact treatment a plurality of times, the number thereof is limited from the effect of reducing glycidol.

< discussion 9: for deodorization conditions >

In the investigation of FIG. 9, the conditions under which the deodorization treatment is performed on the fat or oil after the contact treatment, particularly the influence of the temperature of the fat or oil at the time of deodorization, were investigated.

In the study 9, RBD palm oil (manufactured by AAA company, MCPD content 5.45ppm, and glycidol content 8.38ppm) was purified from different batches. The RBD palm oil of the different batches is denoted as "RBD palm oil lot 2" in table 9.

(example 9-1)

Next, using this mixture, the heated and dissolved RBD palm oil was subjected to a contact treatment. During the contact treatment, the temperature of the oil is adjusted to 90 ℃ at 1.0X 10³Stirring was carried out under reduced pressure of Pa or less for 30 minutes. After the contact treatment, the clay and zeolite are filtered off.

The deodorization treatment is performed by a deodorization treatment based on steam distillation. Specifically, the content of dissolved fat is 5.0X 10²Adjusting the temperature of the oil to 200 ℃ under reduced pressure of Pa or below, and performing 40 minutesDistilling with water vapor. The amount of steam blown was 3 mass%/h with respect to the fat or oil.

(example 9-2)

Purified oils and fats were obtained in the same manner as in example 9-1 except that the steam distillation time was changed to 90 minutes for the deodorization treatment.

(examples 9 to 3)

Purified oils and fats were obtained in the same manner as in example 9-1 except that the temperature of oils and fats was changed to 230 ℃ in the deodorization treatment.

(examples 9 to 4)

A purified oil and fat was obtained by treating in the same manner as in example 9-1 except that the temperature of the oil and fat was changed to 230 ℃ and the steam distillation time was changed to 90 minutes in the deodorization treatment.

(examples 9 to 5)

Purified oils and fats were obtained in the same manner as in example 9-1 except that the temperature of oils and fats was changed to 260 ℃ in the deodorization treatment.

(examples 9 to 6)

A purified oil and fat was obtained by treating in the same manner as in example 9-1 except that the temperature of the oil and fat was changed to 260 ℃ and the steam distillation time was changed to 90 minutes in the deodorization treatment.

The contents of MCPD and glycidol, and the reduction ratios, acid values, peroxide values, color tones, and flavors derived from RBD palm oil of the obtained Ex9-1 to 9-6 are shown in table 9.

From the results of investigation 9, it was confirmed that the degree of reduction of MCPD and glycidyl compounds varies depending on the subsequent deodorization conditions even when the same contact treatment is performed.

It was confirmed that the effect of reducing glycidyl esters was increased by performing the deodorization treatment at a relatively low temperature. Further, it was confirmed that the flavor of the purified oil and fat obtained by the deodorization treatment at a relatively high temperature was improved, but the effect of reducing MCPD and glycidyl oils tended to decrease when the deodorization treatment was carried out at a temperature exceeding 250 ℃.

From these results, it was confirmed that it is important to consider the contact treatment and the subsequent deodorization conditions from the viewpoint of obtaining a high MCPD-based or glycidyl oil-based reduction effect and improving the flavor of the obtained purified oil and fat.

< discussion 10: for the purified object >

In the study 10, the influence of the change in the type of the fat or oil to be purified was studied by focusing attention on MCPD.

(example 10-1)

Purified fats and oils were obtained by treating the oils and fats in the same manner as in example 2-2 except that RBD palm olein (separated soft oil obtained by separating RBD palm oil, manufactured by AAA, 56 iodine value, 6.87ppm content of MCPD) was used as a purification target in place of RBD palm oil.

(example 10-2)

Purified fats and oils were obtained by treating the oils and fats in the same manner as in example 2-2 except that RBD super olein (a soft fraction oil obtained by further separating RBD palm olein, manufactured by AAA, having an iodine value of 65 and an MCPD content of 5.26ppm) was used as a purification target in place of RBD palm oil.

(example 10-3)

Purified oils and fats were obtained by treating RBD palm oil (manufactured by AAA company, MCPD content 5.13ppm, and glycidol content 5.78ppm) in different batches in the same manner as in example 2-2, except that the oils and fats were purified.

The contents of MCPD compounds and the reduction rates, acid values, peroxide values, color tones and flavors of the MCPD compounds derived from the raw material oils and fats are shown in Table 10 for the obtained Ex10-1 to 10-3.

From the results of the study 10, it was confirmed that the method for producing a purified oil or fat of the present invention, which comprises a contact treatment of bringing clay into contact with zeolite, can produce an oil or fat having a low acid value and peroxide value, a clear color tone, and a good flavor while achieving an effect of reducing MCPD, regardless of the kind of the oil or fat, at least in the case of palm-based oils and fats.

Further, when the purification method of the present invention was applied to batches of RBD palm oil different in the amount of MCPD compounds and the amount of glycidyl compounds before purification by comparing Ex2-2 with Ex10-3 and Ex9-4, it was confirmed that MCPD compounds and glycidyl compounds were sufficiently reduced in any of the batches.

Claims

1. A method for producing a purified oil or fat, comprising:

and (3) contact treatment of contacting the oil and fat with clay and zeolite.

2. The method of claim 1, wherein,

3. The method of claim 1 or 2,

the temperature of the grease in the contact treatment is 50-260 ℃.

4. The method according to any one of claims 1 to 3,

in the contact treatment, 0.1 to 3.5 parts by mass of zeolite is used per 100 parts by mass of the oil or fat.

5. The method according to any one of claims 1 to 4,

the clay is activated clay.

6. The method according to any one of claims 1 to 5,

7. The method of any one of claims 1-6, further comprising:

the contact-treated fat or oil is subjected to deodorization treatment for deodorization.

8. The method of claim 7, wherein,

the temperature of the grease in the deodorization treatment is 180-270 ℃.

9. The method according to any one of claims 1 to 8, wherein the fat or oil subjected to the deodorization step is subjected to 1 or more times.

10. A purified oil or fat obtained by the method according to any one of claims 1 to 9,

the purified oil has a total content of chloropropanediol and fatty acid esters thereof of 4ppm by mass or less.

11. A purified oil or fat obtained by the method according to any one of claims 1 to 9,

the purified oil and fat has a total content of glycidol and fatty acid esters thereof of 3ppm by mass or less.

12. A method for reducing chloropropanediols and fatty acid esters thereof or glycidol and fatty acid esters thereof in oils and fats, which comprises:

and (3) contact treatment of contacting the oil and fat with clay and zeolite.

13. A decolorant for grease and oil,

14. A reducing agent for chloropropanediol and fatty acid esters thereof or glycidol and fatty acid esters thereof in oils and fats, wherein,

the zeolite is contained in an amount of 0.1 to 2.5 parts by mass based on 1 part by mass of clay.