JP2655318B2 - Filter material for edible oil regeneration and edible oil regeneration method using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filter medium for removing increased or degraded substances from used or used edible oil and a method for regenerating edible oil using the same. The present invention relates to a filter medium that can be used to filter oil generated daily, and a method for regenerating edible oil using the same.

[0002]

2. Description of the Related Art In-use or used edible oils may be affected by seeds (food used for frying, etc.) or may be colored by chemical changes such as oxidation, hydrolysis and polymerization when heated. Undesirable food products such as odors, oxidized substances, acidic substances, and polymers are produced. Odor-causing substances and oxidizing substances are mainly low-molecular substances having carbonyl groups generated by oxidative deterioration, and those causing acidic substances are mainly low-molecular substances oxidized to carboxylic acids generated by oxidizing deterioration. The main component of the polymer is an unsaturated bond that is oxidized to generate hydroperoxide, and a free radical generated by decomposition of the hydroperoxide causes polymerization by a radical mechanism with another unsaturated bond. Increases oil viscosity.

[0003] As a method for regenerating so-called deteriorated edible oil containing such bad smells, oxidized substances, acidic substances, polymers, etc., only solid substances such as residue of seeds obtained by using filter cloth or filter paper are used. A simple method to remove odors, and furthermore, contact with an adsorbent to adsorb and separate odors, oxidized substances, acidic substances, etc.
Thereafter, a method of forcibly filtering the adsorbent together with other solid substances, a method of filtering the adsorbent itself as a filter material, and the like have been proposed. The method of filtering with a filter cloth or filter paper only removes solid matter, and does not reach the point of removing the deteriorating component generated by the chemical change. As a method using an adsorbent, contact stirring with clay or clay mixture,
After that, it is a method of forcible filtration and is a method used in an essential oil factory or the like. However, it is disadvantageous in that it becomes large in equipment and difficult to adopt in a food factory or a restaurant. Many cooking oils used in food factories and restaurants are
Vegetable oils and fats such as soybean white squeezed oil. Table 1 shows the fatty acid composition of the main vegetable oils and fats. From Table 1, most of these fats and oils were oleic, linoleic,
It can be seen that it is a triglyceride of a fatty acid having 18 carbon atoms such as linolenic acid.

[0004]

[Table 1]

[0005] Activated alumina and silica gel are ones that have characteristic values of the specific surface area, pore volume and pore diameter of the filter medium suitable for adsorption filtration of deteriorated edible oil and exhibit excellent edible oil regeneration performance. However, they are highly chemically processed products and are not economical. Activated alumina also has the disadvantage that it has not been approved as a food additive. Further, in order to avoid complicated means, a method has been proposed in which the adsorbent is processed into a filter medium using the adsorbent itself and the deteriorated edible oil is adsorbed and filtered by the filter medium. As the adsorbent, activated carbon, activated alumina, activated clay, zeolite, silica gel and the like are well known. In examining the relationship between the specific surface area, pore volume, and pore diameter of these porous adsorbents and the adsorption of edible oils or the adsorption of altered substances, it was found that the above physical property values were significantly related to the adsorption. did. Table 2 shows the values of specific surface area, pore volume, and average pore diameter.

[0006]

[Table 2]

As shown in Table 1, most of the fatty acids of vegetable fats and oils are triglycerides of fatty acids having 18 carbon atoms, and the sizes of these molecules are considered to be substantially the same. Due to the influence of seeds, polymerization by heating, hydrolysis, and oxidative decomposition, many molecules of polymers, low-molecular-weight malodorous components, oxides, and acidic substances not contained in fresh edible oil are generated. These produced molecules are apparently the molecular size of triglyceride, and it is considered that the presence of molecules having different molecular sizes is deeply related to the physical property values of the porous adsorbent and the adsorption of the deteriorated or altered substance. As shown in Table 2, activated carbon, zeolites, and silica gel for drying generally have a small pore size and a distribution of about several to 40 mm. Silica gel, which has a small effect of adsorbing and removing substances and coloring substances, while the pore diameter is distributed in a range of about 50 mm or more,
It has been found that activated alumina, activated clay and the like have an adsorptive removal effect, and the greater the pore volume, the greater the adsorptive removal effect. For reference, Table 2 also shows the chromaticity and acid value of the degraded edible oil filtered by each filter medium.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to overcome the above-mentioned problems of the prior art and to provide not only solid substances such as seed residues from degraded edible oils, but also odors, oxidized substances, acidic substances, etc. It is an object of the present invention to provide an economical filter medium capable of adsorbing and separating substances and polymers and easily regenerating edible oil by adsorption filtration, and a method for regenerating deteriorated edible oil using the same. In view of the physical properties described above, the specific surface area, pore volume, and pore diameter of natural minerals that are economical are investigated. Sepiolite and cristobalite are effective (also listed in Table 2 above). The adsorption filtration test was conducted on the deteriorated edible oil, and it was found that sepiolite was particularly effective in removing the deteriorating substances, and the present invention was reached.

[0009]

The above object can be attained by providing a filter medium for regenerating edible oil made of sepiolite and a method for regenerating edible oil using the same according to the present invention. That is, (1) Ri CaO and 12% der total content of 2% MgO as minerals in carbonates, from 650 ° C. to 850 ° C.
A filter medium for regenerating edible oil, comprising sepiolite which has been calcined at a temperature . ( 2 ) The particle size distribution of the sepiolite is 0.1 to 2.0 m.
In m, above, wherein the average particle diameter of 0.3 to 0.7 mm (1) Edible oil regeneration filtration material according to claim. ( 3 ) A method for regenerating edible oil, which comprises regenerating edible oil by filtration using the filter medium containing sepiolite according to the above (1) or (2) . It is.

[0010] Sepiolite (Sepiolite) is _{Mg 8 Si 12 O 30 (OH} ) 4 (OH 2) 4 · 8H hydrous magnesium silicate mineral having a channel structure in a fibrous with ₂ O chemical composition. However, sepiolite is often calcite (CaCO ₃ ), magnesite (MgCO ₃ ), dolomite ((Ca, Mg) CO ₃ )
And a carbonate mineral such as Of course, other minerals may accompany it. The above (1) to
In the item (3) , the filter medium for edible oil regeneration characterized in that it contains sepiolite means that it is accompanied by other minerals. However, the main component of the filter medium of the present invention is sepiolite having the above chemical composition. In addition, the total amount of CaO and MgO described in the above item (1) is the amount of the total amount of CaO and MgO as carbonates contained in sepiolite expressed as a percentage of the total amount of minerals.

[0011]

[Effect] Sepiolite is produced all over the world, such as Spain, Turkey, and China, but the one used in the present invention is a mass of short fibers from Spain.
At about 0 m ² / g, the value is extremely large as a natural mineral. The pore diameter is widely distributed around 100 to 400 °, the average pore diameter is around 100 °, and the pore volume is 0.5 ml.
/ G and a large volume. The pore diameter in this region is different from the micropore that adsorbs gaseous molecules, and is the minimum diameter for sucking up a liquid substance by capillary action. This unique pore is considered to be a void between fibers. The fact that macromolecules such as viscous substances and coloring substances increased by thermal polymerization are well removed by sepiolite is presumed to be closely related to the peculiar pore diameter of sepiolite.

Further, it has been found that the acid value, which is one of the indicators of edible oil deterioration, also decreases. The acid value is a numerical value expressing the amount of potassium hydroxide required for neutralizing the acidic substance contained in 1 g of fat or oil in mg. (See Table 2) The acidic substance contained in fats and oils is a carboxylic acid generated by decomposing triglycerides, and particularly in a deteriorated edible oil, may contain components decomposed to acetic acid and formic acid.

It has been found that the effect of decreasing the acid value can be further improved by firing sepiolite, and that the acid value can be maintained. This is because, as mentioned above, sepiolite often contains calcite (CaCO ₃ ), magnesite (MgCO ₃ ), dolomite ((Ca, Mg) CO ₃ )
And a carbonate mineral such as It is considered that these carbonates are decomposed by firing, for example, by the following reaction to become oxides, and the neutralization reaction with the acidic substance easily proceeds. CaCO ₃ → CaO + CO ₂ Therefore, the greater the content of carbonate mineral, the greater the effect of firing.

Baking is not only effective in lowering the acid value, but also removes organic components contained in sepiolite, which may cause an unpleasant odor, and is therefore preferable from the viewpoint of food hygiene. However, although these CaO and MgO are effective for deoxidation, undesirable effects appear when they are contained in large amounts.
Unwanted side effects include calcium and magnesium,
Fats and soaps which are hydrolyzed by the saponification action are formed, and an indelible foam may be generated during frying. As a result of the experiment, the total amount of CaO and MgO as carbonate minerals was 8
%, No foam was observed, but the total amount was 13%.
In the sample containing, generation of bubbles was observed. Therefore, the total amount of CaO and MgO is preferably about 2 to 12%.

[0015] The calcination temperature is related to the decrease of the acid value, especially its persistence (Fig. 1). Also, as shown in FIG.
The relationship between the combined amount of O and MgO and the deoxidizing effect becomes clear by successively filtering the same deteriorated edible oil. That is,
In the first stage of filtration, the combined amount of CaO and MgO is 1.
If it is 6% or more, the acid value (AV
Value) is reduced to a value similar to that of new oil, but the second time, the difference appears remarkably depending on the total amount. In the example of FIG.
It seems that the difference between the two is remarkable. Observing this as a difference in the firing temperature, it is apparent from the relationship between the firing temperature of sepiolite shown in FIG. 1 and the AV value of the filtered oil treated with the sepiolite fired at that temperature, that is, 600 ° C.
And 700 ° C. Table 3 shows the amounts of CaO and MgO in each sample sepiolite in FIG. 2 and the total amount thereof.

[0016]

[Table 3]

A large difference appears between two or more filtrations of filtration oil filtered using a filter medium from sepiolite having a calcination temperature of 600 ° C. and a filter medium from sepiolite having a calcination temperature of 700 ° C. It seems to be related to the fact that the decomposition onset temperature appearing in the analysis result of the thermal decomposition of calcite (CaCO ₃ ) by DTA and TG in FIG. 3 is about 650 ° C. However, if the firing temperature is too high, as shown in Table 4, a large change occurs in the physical property values inherent to sepiolite.
~ 850 ° C is desirable.

[0018]

[Table 4]

The present invention is intended for edible oils used almost daily, such as in food factories and restaurants, and greatly affects the filtration time. The smaller the particle size of the filter medium, the greater the area of contact with the edible oil. The finer the particle size, the larger the contact area with the oil and the more effective it is in removing the deteriorating components.
Causes clogging during filtration. Therefore, the particle size distribution of the filter medium is 0.1 to 2 mm, and the average particle size is 0.3 to 0. 7 mm,
The layer thickness of the filter medium is suitably from 100 to 200 mm.

[0020]

EXAMPLES Hereinafter, the edible oil regenerating method of the present invention will be specifically described with reference to Examples, but the present invention is not limited by the following description. Example 1 A sample of a commercially available sepiolite (trade name: Milcon G, manufactured by Showa Mining Co., Ltd.) was used.
Baking at each temperature of 600 ° C, 700 ° C and 800 ° C 5
A sample was prepared. The characteristic value of the commercial product is that the particle size distribution is 0.1
As for the accompanying carbonate mineral, calcite is 4.7% as CaO, and magnesite or dolomite (or both) is 1.4% as MgO. These samples were packed in a column of 40 mmφ to a layer thickness of 200 mm, 250 ml of degraded edible oil was injected, allowed to flow naturally, and the acid value (AV
Value) was measured. The results are shown in Table 5. (The results in Table 5 are the same as those shown in the graph of FIG. 1.) As can be seen from Table 5, the deoxidizing effect is clearly improved by the calcination treatment.

[0021]

[Table 5]

In comparison between the dried product and the product fired at 500 to 600 ° C., the deoxidizing effect of the fired product is improved by about 20%. However, its persistence is still poor. A baked product at 700 ° C. or higher has almost twice the deoxidizing effect as compared with a dried product, and has sustainability. The development of the calcining effect almost coincides with the result of the thermal analysis of calcite shown in FIG. 3 indicating that the decomposition start temperature is about 650 ° C., and is considered to support the development of the deoxidizing effect of calcium oxide. The odor of the filtered and regenerated oil was unpleasant in the dried product, but not in the calcined product at 500 ° C. or higher.

[0023]

【The invention's effect】

1. It is an economically inexpensive filter medium obtained by crushing and classifying sepiolite ore and adjusting the particle size to a certain range, but the edible oil filtered using it contains few colored substances and acidic substances, and it is a filter medium made of sepiolite. Is an excellent edible oil regeneration filter medium that can effectively remove coloring substances and acidic substances. 2. Furthermore, by firing the sepiolite filter medium,
The removal of acidic substances can be made persistent. 3. Further, no odor is perceived by the edible oil filtered by the baked product.

[Brief description of the drawings]

FIG. 1 is a graph showing the relationship between the number of filtrations and the acid value using the sepiolite filter medium firing temperature as a parameter.

FIG. 2 is a graph showing the combined amount of CaO and MgO as carbonates, the deoxidizing effect, and the persistence of the calcined product at 800 ° C.

FIG. 3 is a diagram showing the results of thermal decomposition analysis of calcite by DTA and TG.

Claims (3)

(57) [Claims] 1. CaO and Mg as carbonates in constituent minerals
The total amount of O is Ri 12% der 2%, 850 from 650 ° C.
A filter medium for regenerating edible oil, comprising sepiolite which has been calcined at a temperature of up to ° C. 2. The particle size distribution of the sepiolite is from 0.1 to 2.
The filter medium for edible oil regeneration according to claim 1, wherein the filter medium is 2.0 mm and has an average particle size of 0.3 to 0.7 mm. 3. A method for regenerating edible oil, comprising filtering and regenerating edible oil using the filter medium containing sepiolite according to claim 1 or 2 .