JP2005008676A - Silica-magnesia formulation for removing iron and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a silica-magnesia formulation for removing iron composed of a material authorized as a food additive in Japan and effectively used for applications for refining a liquid food product, and the like, each containing iron which is toxic or unnecessary or in an amount more than necessary including especially refining of an edible oil or the refining of the repetitively used edible oil. <P>SOLUTION: The formulation comprises a silica ingredient and a magnesia ingredient in a ratio to provide a weight ratio (R) represented by the formula R=Sw/Mw (wherein, Sw is the content of the silica ingredient expressed in terms of SiO<SB>2</SB>; and Mw is the content of the magnesia ingredient expressed in terms of MgO) within the range of 1.3≤R≤3.0. At least a part of the silica ingredient and that of the magnesia ingredient form a three-layer structure in which the magnesia ingredient layer is sandwiched between the silica ingredient layers. The formulation has ≥20 μg (Fe)/g iron adsorption ability. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【００７４】
【発明の効果】
本発明の鉄分除去用シリカ・マグネシア系製剤は、食品添加物として認可されているシリカ及びマグネシア成分からなっているため、食品精製の用途にも有効に適用できる。
また、シリカ成分層がマグネシア成分層をサンドイッチした微小三層構造を有していることから、鉄分吸着能が著しく高いという特性を有している。
従って、鉄分を多く含む繰返し使用により劣化した食用油の再生をはじめ、有害もしくは不要乃至は必要以上の鉄分を含有する液状食品等の精製に特に適している。
【図面の簡単な説明】
【図１】本発明の鉄分除去用シリカ・マグネシア系製剤におけるナノ複合化と構造について模式的に表した図である。
【図２】実施例５、比較例１、比較例３、比較例５、比較例６及び比較例７による各粉末試料の粉末法Ｘ線回折像である。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an iron-removing silica / magnesia preparation and its production, and more particularly to an iron-removing silica / magnesia preparation useful as a food refining preparation and a method for producing the same. In more detail, especially for the purification of liquid foods such as concentrated seasonings containing harmful, unnecessary or unnecessary iron, including the refining of edible oils and the regeneration of edible oils that have deteriorated due to repeated use. The present invention relates to a preparation useful as a reducing agent and its production.
[0002]
[Prior art]
Conventionally, as silica-magnesia compound, MgO-SiO ₂ -H ₂ It is known that the following magnesium silicate minerals are synthesized from O-based raw materials by hydrothermal treatment under autogenous pressure in a closed container such as an autoclave.
[0003]
For example, 3MgO-4SiO ₂ It has been reported that talc-type magnesium silicate is produced when hydrothermally treated at 280 ° C. under a pressure of 950 psi for 168 hours using a coprecipitate of the following composition as a raw material (see Non-Patent Document 1).
[0004]
Also, a slurry prepared from an amorphous silicic acid raw material such as ferrosilicon dust, a bitter earth raw material, and water is 9 kg / cm. ² A method of producing a magnesium silicate hydrate having low crystalline water repellency by hydrothermal treatment under a pressure of less than that is known (see Patent Document 1).
[0005]
Furthermore, a synthetic layered magnesium phyllosilicate having a specific emulsification performance and a large specific surface area and adsorption capacity by hydrothermal treatment of activated silicic acid or activated aluminosilicate obtained by acid treatment of clay mineral and magnesium raw material Has been proposed (see Patent Document 2).
[0006]
On the other hand, it is also known that magnesium silicate synthesized by, for example, a metathesis reaction (coprecipitation reaction) of sodium silicate and magnesium sulfate is commercially available and used as a general adsorbent.
[0007]
Moreover, as a continuous usage method of used cooking oil, the adsorbent which mixes diatomaceous earth in the ratio of 20-30 weight% with respect to the silica * magnesium-type gel which consists of magnesium oxide and white clay, is edible after cooking. A method of mixing and filtering at an oil temperature of 80 to 120 ° C. every time edible oil is used at a ratio of 0.5 to 3.0% by weight with respect to the oil has been proposed (see Patent Document 3). However, the white clay constituting the silica-magnesium-based gel here refers to activated white clay recognized as an existing additive separately from the designated additive silicon dioxide (silica) (non-patent document). 2) This is clearly distinguished from the silica-magnesia preparation of the present invention described in detail later.
[0008]
Furthermore, magnesium oxide, calcium oxide, magnesium carbonate, calcium carbonate, calcium silicate, magnesium silicate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, synthetic phyllosilicate for deoxidation of edible oil and regeneration of deteriorated oil It has also been proposed to use a deoxidizer selected from magnesium, silicon dioxide and activated clay and granulated to a particle size of 50 to 200 μm (see Patent Document 4).
[0009]
Of course, as a very common sense method, those specified as adsorbents and filter aids for food production in Japan, such as silicon dioxide (silica), magnesium oxide (magnesia), magnesium carbonate, acid clay, activated clay It is clear that the use of diatomaceous earth, activated carbon, etc., in a single use or in combination, attempts to regenerate deteriorated edible oils, even without looking at the upper example (see Non-Patent Document 3).
[0010]
[Non-Patent Document 1]
JULIE CHI-SUN YANG, “Journal of The American Ceramic Society”, 43 , No. 10 (1960), 542-549.
[Non-Patent Document 2]
Food Sanitation Research Group / Edit, “Food Sanitation Related Laws and Regulations”, Central Law Publishing (1990), (1) 406 bottom, (1) 4104 top
[Non-Patent Document 3]
Kawabata Toshiharu et al./Co-edition, “Food Hygiene Encyclopedia”, Central Law (1979), 434-435.
[Patent Document 1]
JP 58-9812
[Patent Document 2]
JP 61-10020
[Patent Document 3]
JP 2001-207187 A
[Patent Document 4]
JP 2001-335793 A
[0011]
[Problems to be solved by the invention]
For the purpose of promoting effective use and reuse of resources, especially the promotion of the Food Recycling Law, for example, to suppress deterioration of oil that is repeatedly used as oil in food business, It is extremely meaningful to increase or reduce the number of times the oil is used by removing or reducing various impurities as unnecessary components and to recycle the oil by re-refining in the middle.
Inventing an adsorbent that can remove or reduce various impurities from edible oil deteriorated by repeated use is extremely significant in terms of providing a material that can realize the above-mentioned object.
[0012]
However, it is not specified in Japan as being usable as an adsorbent for food refining or a filter aid, for example, the magnesium silicate mineral described in Non-Patent Document 1 described above, which is commercially available as a general adsorbent. In the present Japan, the metathesis method synthetic magnesium silicate and the magnesium silicate described in Patent Documents 1, 2 and 4 cannot be used for the purpose of refining foods. .
[0013]
In addition, among those listed in Patent Document 4, when a single substance or a mixture of strong alkaline substances such as magnesium oxide, which is also a designated food additive, is used for the purpose of refining deteriorated edible oil, at a high temperature, Accelerates hydrolysis of fats and oils and causes salt formation reaction with free fatty acids to produce fatty acid magnesium and other metal soaps that dissolve and migrate into the treated oil, impairing the flavor of the oil, etc. There is also anxiety that this may result in
[0014]
[Importance of oil deterioration and iron reduction]
Oil used as pumped oil is generally called “tempura oil”, and is also called “white squeezed oil” for business use. In addition, “salad oil” as raw cooking oil is often used as a deep-fried oil at home. These are substantially the same in the raw material oil and the refining process, and rapeseed oil and soybean oil are mainly used as the raw material oil of “tempura”.
In the case of a general deep-fried food, the optimum temperature is 160 to 180 ° C. However, including the case of a relatively low temperature potato chip to an extremely high temperature fried rice cake, 130 to 270 ° C. is a temperature range in which the deep-fried food is performed. Since the oil in the frying pan is repeatedly exposed to such a high temperature for a long time before being consumed, various changes (deterioration) mainly by oxidation and hydrolysis proceed in the oil.
[0015]
The important causes of oil degradation include the formation of oxidized polymers, thermal polymers, peroxides, oxidative degradation products, thermal decomposition products and colored substances by thermal oxidation, the production of free fatty acids by hydrolysis, There is elution and transfer of trace heavy metals from the material of the inner wall of the frying equipment) and the seeding components. In addition, the oxidation reaction (deterioration) and coloring of the oil are promoted both by reusing by heating and at the time of storage after frying by the oxidizing iron or copper transferred to the oil or their compounds.
[0016]
It is well known that trace amounts of metals, particularly heavy metals with an oxidizing action, promote oil oxidation. Among copper, iron, manganese, chromium, nickel, vanadium, etc., especially copper is said to promote oxidation of fats and oils in a very small amount, and iron has the strongest action after copper.
[0017]
Originally, when fats and oils undergo a refining process, heavy metals derived from these raw materials have also decreased significantly. For example, C.I. D. According to Evans et al., In the case of soybean oil, the amount of copper is 0.1 ppm and the amount of iron is 5.6 ppm. In the case of salad oil that has undergone the refining process, the amount is reduced to 0.005 ppm of copper and 0.08 ppm of iron.
[0018]
Most of the increase in the heavy metal content during repeated use is eluted and transferred from the metal material and / or the seed of the frying device in contact with the oil. For this reason, it is said that it is not very good to use copper or brass as a frying device, etc., and aluminum with no weak metal elution but low strength is avoided, and in reality it is made of mild steel or stainless steel. Steel ones are used.
[0019]
As mentioned above, since the actual frying device is made of iron-based material, most of the trace heavy metals that elute and migrate from the part in contact with the oil of the device are mostly iron. I can say that.
In addition, the transition metal content from deep-fried to deep-fried oil has various trace metal components including naturally-derived iron from vegetables and wild plants, but it is derived from blood components such as livestock meat, whale meat, and fish meat including blood. The iron content of heme iron accounts for the majority.
[0020]
In this way, among heavy metals in pumped oil that increase due to repeated use, in terms of quantity or strength of action, it promotes the deterioration of pumped oil, such as the formation of oxidized polymers, peroxides, and oxidized decomposition products by thermal oxidation. It can be considered that the most adverse effect is iron.
Therefore, it is extremely important to remove iron in the oil as much as possible in order to practically control the deterioration of the oil.
[0021]
By removing trace amounts of naturally-occurring heavy metals contained in edible oil raw materials and heavy metals that have increased through repeated use, especially iron that has an oxidizing and decomposing action, it is harmful to humans. Suppresses the production of colored substances consisting of polymers, iron compounds, etc., and absorbs and removes free fatty acids that are produced by hydrolysis of oil that occurs in contact with water or water vapor generated from frying, and has a significant adverse effect on flavor. Therefore, the significance of refining or regenerating the oil is extremely great. In addition, it is more significant if other harmful or unnecessary components already contained in the deteriorated edible oil can be simultaneously adsorbed and removed.
[0022]
Therefore, in the food business, it is an extremely important issue to be solved to remove or reduce the iron content in the oil pumping increased by repeated use in the middle by using an adsorbent.
[0023]
However, as one of the adsorbents, the magnesium silicate group, which is considered to be extremely safe in terms of its components, cannot be used for such purposes in Japan.
Further, when considering the refining and regeneration of edible oil, the synthetic mineral described in Non-Patent Document 1 is crystalline and thus has a small specific surface area and essentially a low adsorption capacity. It is also unsuitable for use in terms of performance. Since the synthetic layered magnesium phyllosilicate described in Patent Document 2 also uses a natural layered clay mineral acid-treated product as a silicic acid raw material, it contains a large amount of iron as an impurity, and is also unsatisfactory in terms of the iron-adsorbing ability of the liver kidney. Therefore, it is unsatisfactory in terms of characteristics for uses such as refining of edible oil and regeneration of edible oil.
[0024]
Therefore, the main object of the present invention consists of what is certified as a food additive in Japan, and is excellent in iron adsorption / removal ability, especially for refining edible oil and regenerating used edible oil. An object of the present invention is to provide an iron-removing silica / magnesia-based preparation useful as a food refining preparation for use and a method for producing the same.
[0025]
[Means for Solving the Problems]
According to the present invention, the silica component and the magnesia component are represented by the following formula:
R = Sw / Mw
In the formula, Sw is SiO. ₂ The content of the silica component in terms of conversion,
Mw is the content of the magnesia component in terms of MgO.
Is contained in a ratio such that the weight ratio (R) is in the range of 1.3 ≦ R ≦ 3.0, and at least a part of the silica component and the magnesia component is sandwiched between the magnesia component layer and the silica component layer. Thus, a silica-magnesia-based preparation for removing iron content is provided, which has an iron adsorption capacity of 20 μg (Fe) / g or more.
According to the present invention, (A) silicon dioxide and (B) magnesium oxide or a hydrate thereof are represented by the following formula:
R = Sw / Mw
In the formula, Sw is SiO. ₂ The amount of silicon dioxide in terms of conversion,
Mw is the amount of magnesium oxide or its hydrate in terms of MgO.
A step of mixing and aging in the presence of water at a temperature of 100 ° C. or lower in the presence of water such that the weight ratio (R) represented by the formula is in the range of 1.3 ≦ R ≦ 3.0; There is provided a method for producing a silica-magnesia preparation for removing iron, characterized by comprising a step of removing water after aging.
[0026]
In the silica-magnesia preparation for iron removal of the present invention,
1. The weight ratio (R) is 1.9 <R <2.1;
2. In the powder X-ray diffraction image, the diffraction angle 2θ (Cu—Kα ray) shows peaks based on the three-layer structure at 20 ± 1 degree, 35 ± 1 degree, and 61 ± 1 degree,
2. Specific surface area is 480m ² / G or more,
3. Used for reprocessing edible oil (especially deteriorated edible oil),
Is preferred.
[0027]
DETAILED DESCRIPTION OF THE INVENTION
The silica-magnesia preparation for iron removal of the present invention is substantially formed from a silica component and a magnesia component approved as an adsorbent for food production and a filter aid, and is a raw material silica (silicon dioxide). ) Particles and magnesia (magnesium oxide) particles do not dissolve in water but are dispersed as nano-order unit particles (nanoparticles) and are uniformly mixed. It is a preparation that is combined and closely combined without generating chemical bonds (interatomic bonds). Therefore, it can be effectively used in a wide range of food refining applications such as refining of edible oil and regeneration of edible oil deteriorated by repeated use.
[0028]
[Nanocomposite and structure in silica-magnesia preparations]
In the present invention, silica (A) and magnesia or its hydrate (B) are homogeneously mixed in the presence of moisture to form an aqueous slurry, followed by aging and further removal of moisture. The desired silica-magnesia preparation can be obtained.
[0029]
That is, silica (silicon dioxide), which is one of the raw materials, can be broken down into colloidal particles or fine aggregated particles (primary or secondary particles) by homogeneous mixing in water, for example, in water. When the other magnesia (magnesium oxide) is put into water and stirred or pulverized, it hardly dissolves. However, due to hydration, a part or all of the crystals (or newly formed hydrate crystals) are produced. Disintegrates or peels to form fine thin layered particles in which a single layer or two or more layers of magnesium hydrate (magnesium hydroxide) are laminated and are dispersed in water.
[0030]
When water is removed from the slurry in which these fine particles are uniformly dispersed and the solid concentration increases, the silica particles (A) and the magnesia hydrate layered particles (B) gradually or rapidly. Since they are charged with opposite polarities, the particles A are oriented in a layered and planar manner on the surface of the layered particle B, and then the fine particles are brought into close contact with each other by water removal (dehydration). As a result, a fine layer structure in which silica particles are oriented and bonded to the surface portion of the magnesia layered particle is formed.
[0031]
The degree of nanocomposite leading to the formation of the microlayer structure varies depending on the weight ratio (R) of the silica component and the magnesia component in the preparation. For example, in the vicinity of R = 2, it is considered that a fine three-layer structure in which a silica component layer sandwiches a magnesia component layer is formed in many composite particles.
[0032]
As shown in the schematic diagram of FIG. 1, when the weight ratio is less than 2 (R <2) and is relatively magnesia-rich (i), the joint portion (FIG. 1) is formed. The part surrounded by ○ is small, silica particles are oriented or adsorbed or bonded to only one side of the magnesia component layer, silica is slightly adsorbed on both sides, or completely separated into a single layer. It can be said that several types of composite particles are mixed, such as layered particles of magnesia hydrate partially laminated in multiple layers (portion surrounded by □ in FIG. 1). .
[0033]
When the weight ratio is around 2 (R≈2), as described above, the silica component layer has a weight ratio that is just right for the formation of a three-layer structure in which the magnesia component layer is sandwiched. It is considered that the composite structure has many micro three-layer structures as shown in ii).
[0034]
Further, when the weight ratio exceeds 2 (2 <R) and the silica is relatively rich (iii), a large amount of silica fine particles that form the above three-layer structure are formed into an entire amorphous matrix. It is considered that the phase is formed in which the minutely divided finely divided three-layer structure particles are diluted so as to be absorbed by the entire amorphous matrix phase. It is done.
[0035]
The above reasoning for the nanocomposite state of these three-like formulations is supported by the powder X-ray diffraction images of these formulations (see FIG. 2).
That is, in the region of R <2, where there is less silica, the plane index (001), (101) and (101) of the magnesium hydroxide fine layered crystal formed by hydration of magnesia and laminated in a plurality of layers Three strong lines based on (110) appear in the vicinity of 18.5 degrees, 38 degrees, and 51 degrees at diffraction angles 2θ (Cu-Kα lines), respectively, and there is little silica for the peak based on the above-mentioned micro three-layer structure. By the way, only a few hill-shaped lines appear at a low intensity around 35 degrees, but as the mixing amount of silica increases, the intensity decreases at 3 places around 20 degrees, 35 degrees and 61 degrees at 2θ. A wide peak appeared. As a matter of course, as the mixing amount of silica increases, the peaks around 18.5 degrees, 38 degrees and 51 degrees (due to the magnesium hydroxide crystal) become weaker, and R becomes about 1.5 or more. Disappeared.
[0036]
As the mixing amount of silica is increased, the nanocomposite particles forming the above-mentioned micro three-layer structure are mostly present in the vicinity of R = 2, and are in three places near 20 °, 35 ° and 61 ° at 2θ. A low-intensity and wide peak (because of the three-layer structure) is observed, and a peak based on a crystal such as magnesium hydroxide is not observed (for example, Example 5 in FIG. 2).
[0037]
In the region of 2 <R, the amount of silica further increases, and in the region of 2 <R, the nanocomposite particles forming the above-mentioned micro three-layer structure and the amorphous matrix phase composed of excess silica that does not affect the structure formation Thus, until R is about 7.5 or less, low intensity and wide peaks (caused by the three-layer structure) are observed at three locations around 20 °, 35 ° and 61 ° at 2θ. At about 10 or more, those peaks were hardly observed, and only a low-intensity and wide amorphous line (caused by the amorphous structure of the silica matrix phase) was observed around 2θ of 22 °.
[0038]
In the present invention, the silica component and the magnesia component are represented by the following formula:
R = Sw / Mw
In the formula, Sw is SiO. ₂ The content of the silica component in terms of conversion,
Mw is the content of the magnesia component in terms of MgO.
It is extremely important that the weight ratio (R) represented by the formula is 1.3 ≦ R ≦ 3.0, particularly 1.9 <R <2.1. That is, as is apparent from the results of Examples and Comparative Examples described later, if there is an excessive amount of magnesia component or silica component, the adsorption capacity for iron decreases, particularly removal of iron from edible oil after repeated use. It becomes unsuitable for the use aiming at.
[0039]
As described above, it is said that heavy metal components in food oils and fats, especially iron and copper, cause quality deterioration even in a small amount. In order to refine or regenerate edible oils, it is important to suppress the formation of harmful oxides and heat coloring during repeated use by removing iron and the like in the oil. In the preparation of the present invention, by including the silica component and the magnesia component in the above-mentioned quantitative ratio, excellent adsorptivity is exhibited for heavy metal components such as iron, particularly iron components combined with organic components.
[0040]
In addition, it is important that at least a part of the silica component and the magnesia component form a micro three-layer structure in which the silica component layer sandwiches the magnesia component layer. That is, since such a three-layer structure is formed in part or in large quantities, the preparation of the present invention exhibits excellent adsorption characteristics not only for heavy metal components other than iron but also for fatty acid components. Seem.
[0041]
Although the mechanism of these adsorptions is not clear, the three-layer structure in which silica is oriented in layers in the magnesia component layer, for example, the end portion has a loose orientation surface without being closely bonded to the magnesia component layer. There is a part of the silica component layer (the part surrounded by the dotted line square in FIG. 1), and it is adsorbed as if the metal part of the heavy metal component is sandwiched between the vacant part (the dotted circle part in FIG. 1) It is also conceivable that the free fatty acid is directly chemisorbed on the end face of the layer structure or the exposed partial surface of the magnesia component layer where the silica component is not bonded.
[0042]
In addition, in the process of forming the three-layer structure, the crystalline magnesia component having a low specific surface area is peeled off in layers, and the resulting fine three-layer structure particles are not laminated with each other and are randomly dispersed. It is considered that there is a large element that the heavy metal component, free fatty acid, or other substance is physically adsorbed on the surface of a vast particle composed of a chemically mild silica component layer.
[0043]
On the other hand, with the addition of a simple dry mixture of silica and magnesia or a single magnesia, the iron adsorption capacity in the test method described later may be somewhat high, but stearic acid and oleic acid, which are free fatty acids from fats and oils, etc. A salt formation reaction with the magnesia component occurs, and a fatty acid magnesium salt, which is a metal soap, is produced. As a result, the fatty acid magnesium salt does not show stable fatty acid adsorption ability, and the produced fatty acid magnesium salt dissolves and migrates in the oil. As a result, the flavor may be significantly impaired.
However, in the present invention, by forming an interface in which silica is oriented in a layered manner in at least a part of magnesia, it is possible to suppress the salt formation reaction and to stably ensure an excellent fatty acid adsorption ability.
[0044]
In addition, for example, in a single magnesia, the apparent iron adsorption capacity (calculated value) is slightly larger because the complex structure of the standard iron compound used in this test method changes due to decomposition due to strong alkalinity and becomes insoluble. This is thought to be because it does not remain (dissolve) in the oil.
However, in the case of actual deteriorated oil after repeated use that contains a lot of iron due to heme iron derived from blood components such as livestock meat, whale meat, and fish meat including blood, a structure in which the iron component is more stable For this reason, the residual iron content of the treated oil is not reduced so much by the action of the free magnesium component as described above.
[0045]
[Iron adsorption test]
The ability to adsorb heavy metals, which is the characteristic performance of the preparation of the present invention, is representatively shown, and the ability to remove iron, which is the most important target component practically, is evaluated by the ability to adsorb iron. When measuring the ability to adsorb and remove iron in oil, the test should be conducted under certain conditions that are more simplified, as are other common tests. In an actual oil pumping system, the fat and oil components thereof are not constant, and the fatty acid composition in glycerides (esters) that are fats and oils varies greatly. Moreover, the compound form of the iron combined with the organic components contained therein is not always constant and is difficult to specify.
In fact, in systems where livestock and fish are often used as seeds and there is a large amount of iron due to heme iron derived from blood components, particularly effective iron adsorption occurs, and conversely, they are not included much. In the system where the iron content eluted from the material of the frying pan is the main component and the content of iron content is very small, there is a tendency that less effective adsorption occurs.
[0046]
In the present invention, the iron removal ability of the test sample is subjected to an adsorption test using the following simplified system, and the iron content in the oil before and after adsorption is determined by atomic absorption spectrophotometry. Tried.
That is, instead of liquid oil and fat, ethyl oleate (ester), which is a similar oily liquid, is used, and iron (III) 4-cyclohexylbutyrate used in an atomic absorption standard as an organic iron component is dissolved. An organic iron solution (1.00 ± 0.15 μg (Fe) / g) having a substantially saturated concentration at room temperature is prepared, and this is used as a model oil for pumping oil containing trace metal components.
Using the model oil, the present inventors have been able to evaluate the heavy metal removal ability of a sample as an iron adsorption ability, as will be described later in detail in Examples.
[0047]
The silica-magnesia preparation of the present invention shows an X-ray diffraction image as shown in FIG. 2 by powder X-ray diffraction, and the formation of the micro three-layer structure as described above is performed in such an X-ray diffraction image. This can be confirmed from the fact that the bending angle 2θ (Cu—Kα line) shows low and wide peaks in the vicinity of 20 degrees, 35 degrees and 61 degrees, respectively. Further, since each peak is wide and broad, magnesium silicate crystals are not formed, and it can be seen that the preparation of the present invention is substantially semi-crystalline or amorphous.
[0048]
[Preferred properties]
Thus, the silica-magnesia preparation of the present invention contains a silica component and a magnesia component in a certain quantitative ratio, and the silica component layer contains a micro three-layer structure in which the magnesia component layer is sandwiched. From 20 μg (Fe) / g or more, preferably 25 μg (Fe) / g or more, particularly preferably 28 μg (Fe) / g or more, and iron adsorption contained in edible oil is effectively removed by adsorption. It can be applied to a variety of uses such as refining of edible oil and regeneration of edible oil that has been used repeatedly.
[0049]
In the silica-magnesia preparation of the present invention, the silica component and the magnesia component are not separated from each other and are closely combined, so that the pH of the suspension is 8.6 to 10.0, particularly 8. It is characterized by being in the range of 7 to 9.0.
[0050]
The silica-magnesia preparation of the present invention has a specific surface area of 480 m in that iron and other impurities (for example, free fatty acids and coloring components) can be stably adsorbed and removed. ² / G or more, 550m ² / G or more, especially 650m ² / G or more is preferred.
[0051]
[Preferred dosage form]
This preparation is preferably a powder having a particle size distribution with a particle content of less than 5 μm of 20% by volume or less, more preferably 12% by volume or less, and particularly 10% by volume or less. That is, by using a powder having a particle content of less than 5 μm within the above range, a stable and uniform purification treatment (adsorption treatment) can be performed, and the filterability of the treated liquid (edible oil, etc.) is improved. The formulation can be easily separated.
[0052]
Further, instead of using as a powder having the particle size distribution as described above, a spherical or elliptical sphere having a diameter or major axis of 5 μm to 5 mm, or a cylindrical particle having a diameter of 0.5 mm or more and an axial length of 50 mm or less. It can also be used. That is, filterability etc. can be improved also by using it as a granular material of a predetermined shape with such a size.
Silica-magnesia preparations with good filterability obtained in this way can be used not only for batch processing in which the oil is added and absorbed / filtered at a concentration of 0.5 to 3.0% in the middle of use, but also for circulation or lifting of oil. It can be used for intermittent or continuous processing by flow filtration.
[0053]
[Production method of silica / magnesia preparation]
In order to produce the above-described preparation for food purification of the present invention, (A) silicon dioxide (silica) and (B) magnesium oxide (magnesia) or a hydrate thereof are used as raw materials.
These are all approved as filter aids or adsorbents for food production, and their use does not limit food purification.
[0054]
Further, as silica (A) and magnesia or a hydrate (B) thereof, it is preferable to select one that facilitates nanoparticulation described later.
For example, as the silica, an amorphous water-containing type is suitable, and it may be produced by either a gel method or a sedimentation method, but a material having small primary particles is suitable, and the specific surface area is small. 150m ² / G or more, especially 300m ² Those having a weight of at least / g are preferred.
Further, as magnesia or a hydrate thereof, one having a small crystallite is preferable, and one in which carbonation with time has not progressed is preferable. Specific surface area is 50m ² / G or more, especially 100m ² / Powder or more is preferably used.
[0055]
As described above, the silica (A) and magnesia or its hydrate (B) have a weight ratio R (Sw / Mw) of 1.3 ≦ R ≦ 3.0, particularly 1.9 <R <2. Use at a rate in the range of .1. That is, when used in such an amount ratio, various characteristics are expressed in a well-balanced manner, and excellent adsorption characteristics for various components, particularly iron, etc. can be ensured.
[0056]
In the present invention, the above silica (A) and magnesia or its hydrate (B) are homogeneously mixed in the presence of moisture to prepare an aqueous slurry, followed by aging and further removal of moisture. By doing so, the intended preparation for purifying silica / magnesia food for removing iron can be obtained.
[0057]
In the preparation of the aqueous slurry, there are no restrictions on the raw materials (A), (B) and the order in which water is added, but when the aggregation or gelation phenomenon (thickening) occurs, the above-mentioned fine particle formation (nanoparticle formation) There is a risk that the progress of the micro three-layer structure or the like may be hindered. For this reason, the solid content concentration of the aqueous slurry is preferably low, but the solid content concentration is preferably high from the standpoint of productivity and economy. Accordingly, the solid content concentration is preferably in the range of 3 to 15% by weight, particularly 8 to 13% by weight.
[0058]
Further, although gelation is likely to occur even by heating, the above homogeneous mixing and aging are preferably performed at a temperature of 100 ° C. or less, particularly 50 to 97 ° C.
[0059]
Preparation and aging of the aqueous slurry by uniform mixing of the raw materials (A) and (B) is generally performed with stirring in a stirring tank equipped with a stirring blade, but is pulverized or dispersed by a wet ball mill or a colloid mill. It can also be done below.
Aging is a process for sufficiently performing the above-described nanoparticulation (fine graining) and layered orientation of silica particles. Homogenous mixing and aging for the preparation of an aqueous slurry includes temperature, slurry charging capacity, etc. Depending on the time, at least 0.5 hour is required. Moreover, it can carry out in a short time, so that temperature is high. In general, mixing and aging are performed for 1 to 24 hours, particularly 3 to 10 hours.
[0060]
Moisture removal after aging is performed by evaporation drying using a spray dryer or slurry dryer, etc., but after dehydration to some extent by means of filtration, centrifugation, etc., box dryers, band dryers Further, drying may be performed using a fluidized bed dryer or the like.
[0061]
As described above, for example, the water content is 10% by weight or less, and silicon dioxide (silica) particles, which are raw material particles, and magnesia particles are intimately combined by dehydration, and at least a part of the silica particle layer is magnesia layered. A silica-magnesia-based preparation having a micro-layer structure joined in parallel to the particles can be obtained in the form of granules, powder, cake or nodule.
These are pulverized, classified, or molded as necessary, and used as a desired particle shape, for example, for food purification.
[0062]
The above pulverization can be performed by a publicly known dry pulverization method, for example, using an impact pulverizer such as an atomizer, a dry ball mill, a roller mill, or a jet mill.
The classification is performed by gravity classification, centrifugal classification, inertia classification, etc. using a normal dry classifier.
By such pulverization and classification, the silica-magnesia preparation for food purification of the present invention is obtained in the form of a powder having a fine particle content of less than 5 μm, for example, of 20% by volume or less.
[0063]
The molding can be performed by any method such as rolling granulation, fluidized bed granulation, stirring granulation, pulverization granulation, compression granulation, extrusion granulation, etc. It is good to shape | mold so that it may not become hard too much, but may have the intensity | strength of the grade which does not pulverize easily. By such molding, for example, in the form of a spherical or elliptical sphere having a diameter or major axis of 5 μm to 5 mm, or cylindrical particles having a diameter of 0.5 mm or more and an axial length of 50 mm or less, the food refining of the present invention. A silica-magnesia preparation for medical use is obtained.
[0064]
The silica-magnesia preparation of the present invention thus obtained is composed of silica and magnesia components that are approved as food additives as described above, and can be effectively applied to food refining applications as well as various kinds. It has excellent adsorptivity to unnecessary components. Particularly, since the silica component layer has a micro three-layer structure in which the magnesia component layer is sandwiched, the iron adsorption capability is remarkably high.
Deterioration due to repeated use, such as regeneration of deep-frying oil, iron content is also removed from the raw materials and boiled juice of concentrated seasonings such as fish shellfish extract and livestock meat extract that contain a lot of iron, and browning reaction during heat concentration ( It is also used effectively for the purpose of suppressing the Maillard reaction) and preventing a decrease in flavor and nutritional value, and for the purpose of removing the iron compound (ferriclysin) which is a coloring component of sake.
In addition, as described above, it can be effectively used for purification by adsorption / removal of heavy metal components as impurities, particularly iron, from widely useful liquids other than food, and by extension, purification and purification of water.
[0065]
Also, silica / magnesia preparations with high fatty acid adsorption ability (0.1 ≦ R ≦ 1.9) and silica / magnesia preparations with high methylene blue adsorption ability and volatile base adsorption ability (2.1 ≦ R ≦ 50) are appropriately combined. In combination with the activated clay and activated carbon, which are generally used for food purification as adsorbents and filter aids, various impurities in deteriorated edible oils are widely reduced, and more advanced regeneration is achieved. Can also process
If necessary, the particle strength can be improved by adding sepiolite, attapulgite, dosonite, and a fired product thereof to the silica-magnesia preparation of the present invention.
Further, the silica-magnesia preparation of the present invention is converted into an antioxidant, for example, herb extract oil, L-asloruvate stearate, tocophenol, polyphenol, epigrocatechin gallate, isopropyl citrate, BHT, BHA, sezamol, sezamorin. , Γ-oryzanol, propyl gallate and the like.
According to the combination with such other refining agents, it becomes possible to highly refine many liquid foods other than deteriorated edible oil.
Examples of the present invention will be described below.
[0066]
[Test method]
The test method of each characteristic item in this specification was as follows.
1. Iron adsorption capacity
The iron adsorption capacity in this example is 1 to 100 g of organic iron (iron (III) cyclohexylbutyrate) solution (ethyl oleate solution) having a concentration of 1.00 ± 0.15 μg (Fe) / g in terms of iron. The following method, which is defined in terms of μg of iron content that can be adsorbed by the g sample, and which is based on the standard oil analysis method [2.6.3.9 Iron (graphite furnace atomic absorption spectrophotometry)] established by the Japan Oil Chemists' Society Measured and calculated.
First, iron (III) 4-cyclohexylbutyrate (reagent, atomic absorption standard, manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in ethyl oleate (reagent grade 1, manufactured by the same company) as an iron component, and room temperature (15 An organic iron solution (0.89 μg (Fe) / g) having a substantially saturated concentration is obtained at ˜25 ° C.
1.00 g of this organic iron solution is accurately weighed into a 10 mL volumetric flask, 150 μL of nitric acid is added, and 4-methyl-2-pentanone is further added to make a total volume of 10 mL. Using this as the measurement solution, the iron concentration in the solution is determined by the method described in [2.6.3.9 Iron (graphite furnace atomic absorption spectrophotometry)], and is defined as A (μg (Fe) / g).
Next, 50 g of this organic iron solution is weighed correctly into a conical stoppered Erlenmeyer flask, 0.50 g of a dry sample (110 ° C. × 2 hr.) As a test powder is added, and shaken at room temperature for 2 hours. A clear test liquid 1.00 g separated by filtration with a filter paper (No. 2) is operated in exactly the same manner as in the previous stage, and the iron concentration in the test liquid is determined to be B (μg (Fe) / g).
At this time, the iron adsorption capacity of the sample was determined by the following formula.
Iron adsorption capacity = (A−B) × 100
[0067]
2. Iron reduction rate
The reduction rate to the iron concentration (D) when the iron concentration (C) of the oil raised by actual repeated use is deironed by adding a sample at a ratio of 1 part to 100 parts of the oil. Determined by
Iron reduction rate = (C−D) × 100 / C
However, in this example, the oil used repeatedly in the M employee cafeteria (iron concentration C = 1.15 μg (Fe) / g) was used as the oil to be tested.
In addition, in the iron removal treatment, 30 g of the above-mentioned pumped oil was weighed in a test tube, 0.30 g of a dry sample (110 ° C. × 2 hr.) As a test powder was added, and the mixture was heated and stirred in an oil bath (110 ° C. × 250 rpm × 20 min. The iron concentration was measured in accordance with the standard oil and fat analysis test method [2.6.3.9 Iron (graphite furnace atomic absorption spectrophotometry)] established by the Japan Oil Chemists' Society.
[0068]
3. Specific surface area
In this example, the specific surface area of each powder was measured by the so-called BET method by adsorption of nitrogen gas. For details on BET theory, refer to the following document.
S. Brunauer, P.M. H. Emmett, E .; Teller, J.M. Am. Chem. Soc. , Vol. 60, 309 (1938)
In this specification, the specific surface area is usually measured by placing about 0.10 to 0.15 g of the sample in an adsorption sample tube attached to a fully automatic surface area measuring device (Multisorb 12 manufactured by Yuasa Ionics Co., Ltd.). Dry in a constant temperature oven at 2 ° C. for 2 hours and immediately weigh the weight. After predetermined deaeration treatment at 150 ° C. (mantle heater set temperature: 191 ° C.), nitrogen gas was introduced, and the specific surface area was measured according to the program of the apparatus.
[0069]
4). pH
In this example, 1 g of a sample dried at 110 ° C. for 2 hours is weighed in a beaker, and distilled water newly decarboxylated by boiling is added to make the total amount 50 g. Disperse by applying ultrasonic waves for 1 minute, let stand for 1 hour, and then gently stir with a glass rod to make a 2% suspension. Glass electrode type hydrogen ion concentration meter (M-12, Horiba, Ltd.) Was used to measure the pH value (automatic calibration) at 25 ° C.
[0070]
5. Powder method X-ray diffraction
In the present Example, it measured with Cu-K (alpha) using the Rigaku Denki Co., Ltd. X-ray-diffraction apparatus (RINT2000 system). The diffraction conditions are as follows.
Target: Cu
Filter: Curved crystal graphite monochromator
Detector: Scintillation counter
Voltage: 40 kV
Current: 20 mA
Scanning speed: 3 ° / min
Step sampling: 0.05 °
Slit: DS1 ° RS 0.15mm SS 1 °
Viewing angle: 6 °
[0071]
[Example 1] to [Example 8]
In Examples 1-10, using commercially available silicon dioxide (Mizusawa Chemical Co., Ltd. Mizuka Sorb C-1) as a silica raw material and commercially available magnesium oxide (Kamijima Chemical Industry Co., Ltd. Starmag U) as a magnesia raw material, The weight ratios (R) defined in claim 1 are R = 1.3, R = 1.5, R = 1.7, R = 1.9, R = 2.0, R = 2.1, respectively. , R = 2.3, R = 3.0, and both raw materials SiO ₂ The raw material is weighed so that the total amount of the silica component content in terms of conversion and the magnesia component content in terms of MgO is 150 g. Next, tap water is added to a 2 L stainless steel tank so that the total amount of powder material added later is 1,150 g, and the powder material weighed in advance is added little by little under stirring (solid Minor concentration: 13%). Stirring is continued, and the temperature is raised to 95 ° C. in about 15 minutes by heating, followed by homogeneous mixing and aging over 10 hours. The slurry is dehydrated by filtration under reduced pressure, and the resulting cake is placed in an electric dryer and dried at 110 ° C. Finally, the dried cake was pulverized with a sample mill (hammer mill type pulverizer) to obtain white fine powders.
Table 1 shows various characteristics of the powder samples obtained in Examples 1 to 8 measured by the test method.
This is one application example of the refining process of oil used repeatedly, and the deironing process for the purpose of reducing iron content was based on the addition of 1%, but according to the silica / magnesia preparation for removing iron content of this example, For example, the iron content reduction rate was 50 to 54%. In the refining process of raw material fats and oils using activated clay or the like, a treatment of adding 2 to 3% is normal, but even in the preparation of this example, for example, when oil is treated by addition of 2 to 3%, a remarkable effect Can be expected to demonstrate.
[0072]
[Comparative Example 1]
It is a commercially available magnesium oxide (Star Mag U manufactured by Kamijima Chemical Co., Ltd.).
[Comparative Example 2] to [Comparative Example 5]
The same operation was performed except that the weight ratios (R) in Examples 1 to 8 were changed to R = 0.8, R = 1.0, R = 4.0, and R = 5.0, respectively.
[Comparative Example 6]
It is a commercially available silicon dioxide (Mizukasorb C-1 manufactured by Mizusawa Chemical Co., Ltd.).
[Comparative Example 7], [Comparative Example 8]
Each powder of magnesium oxide of Comparative Example 1 and silicon dioxide of Comparative Example 6 was dry-mixed by a stirring type small mixer at a ratio of weight ratios (R) of R = 1.7 and R = 2.3, respectively. Was obtained by
[Reference Example 1]
A synthetic layered magnesium phyllosilicate obtained by hydrothermal treatment of active silicic acid and magnesium hydroxide made from acid clay from Matsune, Kushibuki-cho, Yamagata Prefecture, as a raw material by the method of Example 1 of Patent Document 2 above. It is a white fine powder.
Various characteristics of the powder samples according to Comparative Examples 1 to 8 and Reference Example 1 are also shown in Table 1.
[0073]
[Table 1]

[0074]
【The invention's effect】
Since the silica-magnesia preparation for removing iron content of the present invention is composed of silica and magnesia components that are approved as food additives, it can be effectively applied to food purification applications.
Further, since the silica component layer has a micro three-layer structure in which the magnesia component layer is sandwiched, it has a characteristic that the iron adsorption ability is remarkably high.
Therefore, it is particularly suitable for refining edible oil deteriorated by repeated use containing a large amount of iron, and for refining liquid foods containing harmful, unnecessary or unnecessary iron.
[Brief description of the drawings]
BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a diagram schematically showing nanocomposite and structure in a silica / magnesia preparation for removing iron content of the present invention.
2 is a powder X-ray diffraction image of each powder sample according to Example 5, Comparative Example 1, Comparative Example 3, Comparative Example 5, Comparative Example 5, Comparative Example 6 and Comparative Example 7. FIG.

Claims (6)

The silica component and the magnesia component are represented by the following formula:
R = Sw / Mw
In the formula, Sw is the content of the silica component in terms of SiO ₂ ,
Mw is the content of the magnesia component in terms of MgO.
Is contained in a ratio such that the weight ratio (R) is in the range of 1.3 ≦ R ≦ 3.0, and at least a part of the silica component and the magnesia component is sandwiched between the magnesia component layer and the silica component layer. A silica-magnesia-based preparation for removing iron content, characterized in that it has a three-layer structure and has an iron adsorption capacity of 20 μg (Fe) / g or more. 2. The silica-magnesia preparation for iron removal according to claim 1, wherein the weight ratio (R) is 1.9 <R <2.1. 3. The powder method X-ray diffraction image according to claim 1, wherein a diffraction angle 2θ (Cu—Kα ray) shows peaks based on the three-layer structure at 20 ± 1 degrees, 35 ± 1 degrees, and 61 ± 1 degrees. Silica / magnesia preparation for iron removal. The specific surface area is 480 m ² / g or more, and the silica / magnesia preparation for iron content removal according to any one of claims 1 to 3. The silica-magnesia preparation for removing iron content according to any one of claims 1 to 4, which is used for refining edible oil. (A) Silicon dioxide and (B) magnesium oxide or a hydrate thereof are represented by the following formula:
R = Sw / Mw
In the formula, Sw is the amount of silicon dioxide in terms of SiO ₂ ,
Mw is the amount of magnesium oxide or its hydrate in terms of MgO.
A step of mixing and maturing at a temperature of 100 ° C. or lower over at least 1 hour in the presence of water so that the weight ratio (R) represented by the formula is in the range of 1.3 ≦ R ≦ 3.0. And a step of removing moisture after aging, and a method for producing a silica-magnesia preparation for removing iron.

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