Filter for inhibiting degradation of edible oils, and method for producing same

Abstract

Provided is a filter for inhibiting the degradation of edible oils, which can inhibit the degradation of an edible oil efficiently and easily without requiring the use of a filtering aid or the like and can also prevent the detachment of a degradation inhibiting agent to prevent the deterioration in the flavor of a food. The filter for inhibiting the degradation of edible oils comprises fibers (10) and at least one degradation inhibiting agent (13) selected from a carbonate, a silicate, a tartrate, an oxide, a hydroxide, an alginate and a phosphate.

Description

Cooking oil deterioration prevention filter and its manufacturing method

[0001] The present invention relates to a cooking oil degradation suppression filter capable of suppressing oxidative degradation of cooking oil, and a method for producing the same.

[0002] Edible oils are used in a variety of foods, but edible oils used to cook deep-fried foods such as tempura and fries oxidize and deteriorate when heated or left to stand during cooking, deteriorating the taste, odor, and appearance of the food and potentially causing food poisoning. Oxidized oils increase in viscosity and become less easy to drain, so edible oils that have oxidized to levels exceeding a certain standard are discarded. Therefore, from the perspective of protecting the global environment, it is desirable to slow the oxidative deterioration of edible oils as much as possible and reduce the number of times edible oil is discarded. Furthermore, reducing the number of times edible oil is discarded also has the benefit of reducing the number of times deep-frying equipment (fryer) used for deep-frying needs to be cleaned, thereby reducing the amount of water used for cleaning.

[0003] Therefore, various cooking oil filters have been proposed to suppress oxidative degradation of cooking oil. For example, Patent Document 1 discloses a method in which tartrate is used as a cooking oil purification agent and the purification agent is added directly to the cooking oil. Patent Document 1 also describes a filter in which potassium hydrogen tartrate is sandwiched between paper and the edges of the paper are closed to form a bag. Patent Document 2 discloses a filter in which a cooking oil degradation inhibitor is attached to at least one or both of the surface of the filter material and the inner surface of the pores using a binder. Patent Document 3 also describes a cooking oil filter obtained by stirring and mixing fibers such as pulp and an adsorbent such as activated carbon powder in water and dehydrating the mixture by compression molding.

[0004] Japanese Patent No. 6763219 Japanese Patent Application Publication No. 2021-630 Japanese Patent Application Publication No. 4593127

[0005] However, as described in Patent Document 1, when a purifying agent for cooking oil is added directly to cooking oil, the purifying agent may adhere to food and impair the flavor of the food. Also, in the case of a filter structure in which the purifying agent for cooking oil is sandwiched between paper bags, the purifying agent inside may leak when the paper is torn, which may impair the flavor of the food as in the case of direct addition, and there is room for further improvement.

[0006] Furthermore, when manufacturing the filter described in Patent Document 2, it is necessary to manufacture the filter material in advance and attach the additives, which increases manufacturing costs and raises concerns about the increase in environmentally harmful substances and energy required for manufacturing. Furthermore, since the cooking oil deterioration inhibitor is attached to the filter material with a binder, a portion of the deterioration inhibitor is covered by the binder, reducing the contact efficiency with cooking oil. Therefore, a large amount of deterioration inhibitor is required to fully achieve the cooking oil deterioration inhibitor effect.

[0007] Furthermore, the filter described in Patent Document 3 has an adsorbent attached to the fiber, so while it can sufficiently decolorize and deodorize, it cannot sufficiently suppress the deterioration of cooking oil. Therefore, it is difficult to reduce the number of times cooking oil is discarded, and there is room for further improvement from the perspective of protecting the global environment. Furthermore, if the adhesive strength between the fiber and the adsorbent is weak, the adsorbent may fall off the fiber, which may impair the flavor of food, as in the case of Patent Document 1.

[0008] In addition, commonly used cooking oil filters sometimes require a powdered filter aid to be spread on the filter paper. The filter aid has the effect of suppressing deterioration of cooking oil, but because it is in powder form, the powder flies around when it is spread, and when cleaning after filtration, the clay-like filter aid must be collected, which reduces work efficiency.

[0009] The present invention has been made in consideration of these problems, and aims to provide an edible oil degradation-inhibiting filter that can efficiently and easily inhibit edible oil degradation without using filter aids, etc., and that can prevent deterioration of food flavor due to the detachment of the degradation inhibitor. Another aim of the present invention is to provide a method for easily manufacturing an edible oil degradation-inhibiting filter that has excellent degradation-inhibiting function, and that can suppress the generation of environmentally hazardous substances during manufacturing, thereby achieving global environmental conservation.

[0010] In response to these challenges, the present applicant proposed in Japanese Patent Application No. 2021-121669 a technology that can efficiently and easily suppress edible oil degradation without using filter aids or the like, while preventing the flavor of food from being impaired by the detachment of the degradation inhibitor. Japanese Patent Application No. 2021-121669 proposes a method for manufacturing an edible oil degradation suppression filter, also known as a "papermaking method," in which a filter substrate fiber and a degradation inhibitor are added to water and diffused and mixed to prepare an aqueous suspension, which is then dehydrated and dried. This manufacturing method, in which the degradation inhibitor is held by the fibers without the use of binders or the like, efficiently prevents edible oil degradation and easily produces a filter in which the degradation inhibitor is prevented from detaching. Furthermore, because the process for manufacturing the filter medium and the process for attaching the additive can be performed in a single process, increases in manufacturing costs can be suppressed, and the increase in environmentally harmful substances and energy required for manufacturing can be suppressed. Furthermore, since water is used as the dispersion medium, it also contributes to protecting the global environment.

[0011] However, in the above-mentioned production method, when an oxide such as calcium oxide or magnesium oxide, particularly an alkaline earth metal oxide, which is generally known as a deoxidizer, is used as a deterioration inhibitor, a hydration reaction shown in the following formula (1) occurs in the aqueous suspension, and there is a risk that the deterioration inhibitory function will be inactivated sufficiently. ２ O → M (OH) ２... (1) where M is an alkaline earth metal

[0012] Therefore, the present invention also aims to provide an edible oil degradation prevention filter and a method for manufacturing the same, which uses an oxide, particularly an alkaline earth metal oxide, as a degradation prevention agent and, taking into consideration the conservation of the global environment, can prevent the loss of degradation prevention function even when water is used as the liquid in the process of obtaining a suspension during the manufacture of the edible oil degradation prevention filter.

[0013] The above object of the present invention can be achieved by the following configuration [1] relating to an edible oil degradation prevention filter.

[0014] [1] A cooking oil deterioration prevention filter comprising: fibers; and at least one deterioration inhibitor selected from carbonates, silicates, tartrates, oxides, hydroxides, alginates, and phosphates.

[0015] Furthermore, preferred embodiments of the present invention relating to the cooking oil degradation prevention filter relate to the following [2] to

[18] .

[0016] [2] The cooking oil degradation prevention filter according to [1], wherein the degradation inhibitor is at least one selected from the group consisting of tartrates, oxides, and hydroxides. [3] The cooking oil degradation prevention filter according to [2], wherein the degradation inhibitor is an oxide and further comprises a hydration reaction retarder made of a sugar alcohol. [4] The cooking oil degradation prevention filter according to [3], wherein the sugar alcohol is at least one selected from the group consisting of erythritol, glycerin, lactitol, maltitol, mannitol, xylitol, and sorbitol. [5] The cooking oil degradation prevention filter according to [4], wherein the sugar alcohol is either glycerin or sorbitol, or both. [6] The cooking oil degradation prevention filter according to any one of [3] to [5], wherein the sugar alcohol has a molecular weight of 500 or less. [7] The cooking oil degradation prevention filter according to [2], wherein the degradation inhibitor is an oxide and further comprises at least one hydration reaction retarder selected from the group consisting of organic acid salts, sulfates, monosaccharides, and disaccharides. [8] The cooking oil degradation inhibition filter according to [7], wherein the hydration reaction retarder comprises at least one selected from citric acid, calcium sulfate, and sucrose. [9] The cooking oil degradation inhibition filter according to [7] or [8], wherein the molecular weight of the hydration reaction retarder is 500 or less.

[10] The cooking oil degradation inhibition filter according to any one of [3] to [9], wherein the hydration reaction retarder is contained in a trace amount.

[11] The cooking oil degradation inhibition filter according to

[10] , wherein the hydration reaction retarder is contained in an amount of 10 ppm or more per gram of the cooking oil degradation inhibition filter.

[12] The cooking oil degradation inhibition filter according to any one of [1] to

[11] , wherein the fibers comprise beaten fibers.

[13] The cooking oil degradation inhibition filter according to

[12] , wherein the fibers have a trunk portion and branch portions branched from the trunk portion by beating, and the branch portions hold particles containing the degradation inhibitor.

[14] The cooking oil degradation prevention filter according to

[12] or

[13] , wherein the fibers are either or both of natural fibers and artificial fibers.

[15] The cooking oil degradation prevention filter according to

[14] , wherein the artificial fibers are either or both of recycled fibers and synthetic resin fibers.

[16] The cooking oil degradation prevention filter according to any one of [1] to

[15] , wherein the degradation inhibitor is present both inside and on the surface of the fibers.

[17] The cooking oil degradation prevention filter according to any one of [1] to

[16] , further comprising an adsorbent.

[18] The cooking oil degradation prevention filter according to

[17] , wherein the adsorbent comprises at least one selected from silicon dioxide, natural clay, artificial synthetic clay, and activated carbon.

[0017] The above object of the present invention can also be achieved by the following configuration

[19] relating to a method for producing an edible oil degradation prevention filter.

[0018]

[19] A method for producing the cooking oil degradation inhibitor filter according to any one of [1] to

[18] , comprising the steps of obtaining a suspension containing the fibers and the degradation inhibitor, and draining and drying the suspension.

[0019] According to the present invention, it is possible to provide an edible oil degradation-inhibiting filter that can efficiently and easily inhibit oxidative degradation of edible oil without using a filter aid or the like and that can prevent the degradation inhibitor from falling off. Furthermore, according to the manufacturing method of the present invention, it is possible to easily manufacture an edible oil degradation-inhibiting filter that has excellent degradation-inhibiting function. Furthermore, it is possible to suppress the generation of environmentally hazardous substances during manufacturing, thereby realizing global environmental conservation. Furthermore, according to the present invention, it is possible to provide an edible oil degradation-inhibiting filter and a manufacturing method thereof that, taking global environmental conservation into consideration, can sufficiently suppress the deactivation of the degradation-inhibiting function even when water is used as the liquid in the step of obtaining a suspension during the manufacturing of the edible oil degradation-inhibiting filter.

[0020] Fig. 1 is a photograph showing the surface of the cooking oil degradation inhibiting filter according to this embodiment. Fig. 2 is a photograph showing the cross section of the cooking oil degradation inhibiting filter according to this embodiment. Fig. 3 is a schematic diagram showing an example of a cooking oil filter device to which the cooking oil degradation inhibiting filter according to this embodiment can be applied.

[0021] An embodiment of the cooking oil degradation prevention filter according to the present invention will be described below. Note that, hereinafter, the cooking oil degradation prevention filter may be simply referred to as a "filter." Furthermore, this embodiment is merely an example of the present invention, and the present invention is not limited to this embodiment. Furthermore, various modifications and improvements can be made to this embodiment, and such modifications and improvements can also be included in the present invention.

[0022] [Cooking oil degradation inhibiting filter] The cooking oil degradation inhibiting filter according to this embodiment includes fibers and a degradation inhibitor. The fibers and degradation inhibitor that can be used in the cooking oil degradation inhibiting filter according to this embodiment will be described in detail below.

[0023] <Fibers> The fibers used as the filter material can be either natural fibers or artificial fibers, or both. These fibers can be used as they are, but are preferably beaten. Using beaten fibers as the filter material can significantly improve the retention of the degradation inhibitor. The beating process results in fluffing, forming a trunk portion and branch portions branching from the trunk portion. The branch portions are thinner than the trunk portion, and during the manufacturing process, the branch portions become entangled with the particulate degradation inhibitor in the liquid, thereby firmly retaining the degradation inhibitor. Therefore, when used cooking oil is filtered using the filter of this embodiment, the degradation inhibitor can be prevented from falling off and from being mixed into the filtered cooking oil. In the cooking oil degradation inhibitor filter of this embodiment, to achieve sufficient retention of the degradation inhibitor, the diameter of the branch portions is preferably 50% or less of the diameter of the trunk portion, more preferably 40% or less, and even more preferably 30% or less. The term "beaten fibers" includes defibrated fibers.

[0024] In addition, in this embodiment, since the deterioration inhibitor is held in the fibers, preferably beaten fibers, in the filter, there is no need to use a powdered filter aid as is commonly used in filters. Therefore, oxidation deterioration of edible oil can be efficiently and easily suppressed without the use of an auxiliary agent, and there is no need to collect the clay-like filter aid during the filter aid application process or cleaning after filtration, which improves the work efficiency during edible oil filtration. The filter aid may be used as needed, and the amount used can be reduced from that generally used.

[0025] As will be described later, the filter of this embodiment is obtained by draining and drying a suspension containing fibers, preferably beaten fibers, and a deterioration inhibitor.The suspension not only contains particles containing the deterioration inhibitor held in the branch-like portions, but if the deterioration inhibitor is in a dissolved state, it is thought that the deterioration inhibitor is present both inside and on the surface of the fibers, thereby achieving an even greater effect of suppressing the deterioration of edible oil.

[0026] (Natural Fibers) Natural fibers are fibers made from natural substances. The type of natural fiber is not particularly limited, and examples include wood pulp, cotton, wool fiber, hemp, silk, etc. In this embodiment, natural fibers may be used alone, or artificial fibers (described later) may be used alone or both. However, it is preferable to use natural fibers, which have good fluffing properties, as the main component. Note that the term "main component" refers to a state in which the amount of natural fibers used is more than 50% by mass, preferably more than 60% by mass, and more preferably more than 70% by mass, of the total mass of fibers used in manufacturing the filter.

[0027] (Artificial Fibers) When artificial fibers are used, at least one selected from recycled fibers and synthetic resin fibers can be used. Examples of recycled fibers include rayon. Examples of synthetic resin fibers include polyester resin fibers, polyolefin resin fibers (e.g., polyethylene fibers, polypropylene fibers), polyamide resin fibers (e.g., polyamide 66 fibers), vinyl resin fibers, acrylic resin fibers, and polyurethane resin fibers. All of these fibers become fluffy when beaten, and the branched portions can hold the particulate deterioration inhibitor, so the deterioration inhibitor does not fall off and the deterioration inhibitor can be prevented from falling off, thereby achieving the effect of inhibiting deterioration of edible oil.

[0028] Whether the fibers used are natural fibers or artificial fibers, there are no particular limitations on the average fiber length and average fiber diameter, but typically, fibers having an average fiber length of 0.1 to 15 mm and an average fiber diameter of 0.005 to 0.1 mm are preferably used.

[0029] (Other Fibers) In this embodiment, in addition to the natural fibers and artificial fibers, other fibers may be included, such as metal fibers, glass fibers, and carbon fibers.

[0030] <Deterioration Inhibitor> The deterioration inhibitor used in the filter according to this embodiment has the effect of inhibiting deterioration of cooking oil by coming into contact with cooking oil. As the deterioration inhibitor, it is preferable to use at least one selected from carbonates such as calcium carbonate and magnesium carbonate, silicates such as calcium silicate and magnesium silicate, tartrates such as potassium hydrogen tartrate, oxides such as magnesium oxide, calcium oxide and aluminum oxide, hydroxides such as magnesium hydroxide and calcium hydroxide, alginates such as calcium alginate, and phosphates such as trimagnesium phosphate. Among these, it is more preferable to use at least one selected from tartrates, oxides and hydroxides.

[0031] Furthermore, the deterioration inhibitor may be chemically synthesized during the manufacturing process. For example, calcium oxide reacts with water, which is the solvent of the aqueous suspension, to synthesize calcium hydroxide, and the deterioration inhibitor may be present in the filter as calcium hydroxide.

[0032] In the filter according to this embodiment, the mass of the deterioration inhibitor relative to the total mass of the filter is preferably 1% by mass or more, and preferably 80% by mass or less. When the mass of the deterioration inhibitor relative to the total mass of the filter is 1% by mass or more, the effect of suppressing deterioration of edible oil can be obtained. Furthermore, when the mass of the deterioration inhibitor relative to the total mass of the filter is 80% by mass or less, the effect of preventing the deterioration inhibitor from falling off can be obtained. When multiple edible oil deterioration inhibitors are used in combination, it is preferable that their total amount be within the above numerical range. The mass of the deterioration inhibitor relative to the total mass of the filter is more preferably 60% by mass or less, and even more preferably 50% by mass or less.

[0033] The mass of the deterioration inhibitor relative to the total mass of the filter can be calculated, for example, by washing the filter with a liquid that dissolves the deterioration inhibitor but does not dissolve the fibers, dissolving and removing the deterioration inhibitor present on the surface and inside of the fibers, drying the fiber portion, and measuring the mass difference. The mass of the deterioration inhibitor can also be calculated by washing the filter with a liquid that dissolves the fibers but does not dissolve the deterioration inhibitor, dissolving and removing the fibers, drying the deterioration inhibitor portion, and measuring the mass difference. Furthermore, the mass of the deterioration inhibitor can also be calculated by burning and decomposing and removing organic matter, and measuring the ash content.

[0034] When an oxide is used as the deterioration inhibitor, examples of the oxide include oxides of alkaline earth metals, which include the four elements calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra), as well as beryllium (Be) and magnesium (Mg).

[0035] The alkaline earth metal oxide may be used alone, or may be used in combination with other deterioration inhibitors. Examples of other deterioration inhibitors include hydroxides such as magnesium hydroxide and calcium hydroxide, carbonates such as calcium carbonate and magnesium carbonate, silicates such as calcium silicate and magnesium silicate, tartrates such as potassium hydrogen tartrate, alginates such as calcium alginate, and phosphates such as trimagnesium phosphate, which may be used alone or in combination of two or more.

[0036] <Hydration Retarder> As mentioned above, oxides such as alkaline earth metal oxides used as deterioration inhibitors may undergo hydration reactions, which may result in the loss of sufficient deterioration inhibitory function. Therefore, a hydration retarder is used in combination to delay the hydration reaction. Specifically, a sugar alcohol is used as the hydration retarder.

[0037] Specifically, the sugar alcohol is preferably at least one selected from erythritol, glycerin, lactitol, maltitol, mannitol, xylitol, and sorbitol, and among these, it is particularly preferable to use at least one selected from glycerin and sorbitol because of its higher hydration reaction inhibitory effect.

[0038] Furthermore, the sugar alcohol more preferably has a molecular weight of 500 or less, and particularly preferably 250 or less. When the sugar alcohol has a molecular weight of 500 or less, it dissolves well in water, which is the dispersion medium, and the effect of retarding the hydration reaction is further enhanced.

[0039] As in the manufacturing method described below, it is preferable to use an aqueous suspension in consideration of environmental conservation, but oxides such as alkaline earth metal oxides are poorly soluble in water and therefore remain in the filter in particulate form, adhering to fibers, while sugar alcohols are water-soluble and are removed from the filter together with water when the aqueous suspension is drained. However, although only in small amounts, sugar alcohols remain in the filter, adhering to oxides and fibers. The amount of sugar alcohol remaining in the filter is what is known as a "trace amount."

[0040] The sugar alcohol remaining in the filter has the effect of suppressing the hydration reaction between the oxide and moisture in the air or trace amounts of moisture contained in the cooking oil. To ensure this effect, the amount of sugar alcohol remaining in the filter is preferably 10 ppm or more, and more preferably 50 ppm or more, per gram of the cooking oil degradation-suppressing filter.

[0041] Furthermore, as the hydration reaction retarder, at least one selected from organic acid salts, sulfates, monosaccharides and disaccharides can also be used.

[0042] Examples of organic acid salts include citric acid, acetic acid, lactic acid, etc.; citrates such as calcium citrate, potassium citrate, and sodium citrate; acetates such as calcium acetate, potassium acetate, and sodium acetate; and lactates such as calcium lactate, potassium lactate, and sodium lactate. Examples of sulfates include calcium sulfate. Examples of monosaccharides include glucose, fructose, mannose, and galactose. Examples of disaccharides include sucrose. These may be used alone or in combination. Among these, the use of at least one selected from citric acid, calcium sulfate, and sucrose is particularly preferred because of its higher hydration reaction inhibitory effect.

[0043] Furthermore, the molecular weight of these compounds is more preferably 500 or less, and particularly preferably 400 or less. If the molecular weight of these compounds is 500 or less, they dissolve well in water, which is a dispersion medium, and the effect of retarding the hydration reaction is further enhanced.

[0044] Like the sugar alcohols described above, trace amounts remain in the filter and inhibit hydration reactions caused by moisture in the air or trace amounts of moisture contained in cooking oil. To ensure this effect, the amount of hydration reaction retarder remaining in the filter is preferably 10 ppm or more, and more preferably 50 ppm or more, per gram of the cooking oil degradation-inhibiting filter.

[0045] <Other Additives> In addition to the deterioration inhibitor and hydration reaction inhibitor, the filter according to this embodiment may also use an adsorbent having decolorizing and deodorizing effects. The adsorbent is preferably at least one selected from silicon dioxide, natural clay, artificial synthetic clay, and activated carbon. Even when an adsorbent is used, the branches of the beaten fibers can retain the adsorbent, preventing additives from being mixed into the filtered cooking oil and providing excellent decolorizing and deodorizing effects.

[0046] [Method of Manufacturing the Cooking Oil Degradation Inhibition Filter] The cooking oil degradation inhibition filter according to this embodiment is manufactured by first preparing a suspension of (1) fibers, preferably beaten fibers, (2) a degradation inhibitor, and (3) other degradation inhibitors or adsorbents as needed, in a suitable solvent. When natural fibers are used, water can be selected as the solvent, and when artificial fibers are used, a liquid suitable for beating the fibers can be selected.

[0047] In consideration of environmental conservation, an aqueous suspension is preferred, but when an oxide is used as the deterioration inhibitor, a hydration reaction retarder is used in combination. The hydration reaction retarder may be added to the water at the same time as the deterioration inhibitor, but it is preferable to add the deterioration inhibitor after the hydration reaction retarder has been fully dissolved in water, as this more effectively prevents the deterioration inhibitor function from being deactivated.

[0048] To obtain beaten fibers, there is a method in which, when obtaining a suspension, the fibers are put into water together with the above-mentioned components (2) and (3), and then beaten using a beater such as a refiner or beater, or a mixer / disperser such as a dissolver or homomixer. Such a beating treatment can fluff the fibers and also enable the fibers to be uniformly dispersed in the suspension.

[0049] Alternatively, the fibers alone may be first put into water, and after beating treatment using the above-mentioned beater or mixer / disperser, the deterioration inhibitor may be added.

[0050] The suspension may also contain chemicals commonly used in filter manufacturing, such as paper strength agents, retention aids, pH adjusters, and fixatives. The amounts of these chemicals added are not particularly limited as long as they are within the range that does not affect the human body.

[0051] The suspension is then drained and dried to obtain a filter in which particles containing the deterioration inhibitor are held in the fibers. Note that the draining may be performed by evaporating the water or by filtration (papermaking).

[0052] According to the manufacturing method of this embodiment, the deterioration inhibitor is held by the fibers without using a binder or the like, so deterioration of cooking oil can be efficiently prevented and a filter in which the deterioration inhibitor is prevented from falling off can be easily manufactured. Furthermore, since the process for manufacturing the filter medium and the process for attaching the additive can be performed in a single process, increases in manufacturing costs can be suppressed and increases in environmentally harmful substances and energy required for manufacturing can be suppressed. Furthermore, when an oxide is used as the deterioration inhibitor, a hydration reaction retarder is added to the aqueous suspension, which effectively suppresses the hydration reaction of the oxide, which would cause the deterioration inhibitor function to be inactivated.

[0053] To allow trace amounts of hydration reaction retarder to remain, preferably at least 10 ppm per gram of filter, the content of the hydration reaction retarder in the suspension can be adjusted to 0.01% by mass or more, preferably 0.05% by mass or more.

[0054] <Solution Containing Deterioration Inhibitor> The deterioration inhibitor used in this embodiment may be one that dissolves in a solvent other than water. In the above-described manufacturing method, when the beaten fibers and the solution containing the deterioration inhibitor are mixed, the solution penetrates into the fibers, and the subsequent dewatering and drying processes are thought to precipitate fine particles containing the deterioration inhibitor inside the fibers. Furthermore, if particles containing the deterioration inhibitor are contained in the solution during the step of mixing the beaten fibers and the solution containing the deterioration inhibitor, i.e., if the particles are present in the solution in particulate form, the particles are likely to become entangled in the branched portions of the fibers. For these reasons, it is preferable that the solution containing the deterioration inhibitor not only contains the deterioration inhibitor dissolved therein but also particles containing the deterioration inhibitor.

[0055] The cooking oil degradation prevention filter according to the present invention will be further described below with reference to examples, although the present invention is not limited to the following examples.

[0056] Test Example 1: Cotton fiber was used as the natural fiber, calcium oxide and potassium hydrogen tartrate were used as deterioration inhibitors, and activated carbon was used as an adsorbent, and these were put into water and beaten in a mixer, with the cotton fiber accounting for 70% by mass, calcium oxide for 10% by mass, potassium hydrogen tartrate for 10% by mass, and activated carbon for 10% by mass, based on the total mass of the materials other than water.

[0057] The filter was then dehydrated by filtration and dried to obtain a cooking oil degradation suppression filter according to this example. The surface and cross section of the filter were then photographed using an electron microscope to observe the state of the fibers and degradation suppression agent.

[0058] Fig. 1 is a photograph showing the surface of the cooking oil degradation prevention filter according to this embodiment. Fig. 2 is a photograph showing the cross section of the cooking oil degradation prevention filter according to this embodiment. The upper part of Fig. 2 shows the surface layer of the filter cross section, and the lower part shows the middle layer.

[0059] 1 and 2, cotton fibers 10 are beaten to form branch portions 12 branching from a trunk portion 11. Because these branch portions 12 are much thinner than the trunk portion 11, the particulate deterioration inhibitor 13 is entangled and held by the branch portions 12. Regardless of the particle size of the deterioration inhibitor 13 or its position in the surface layer, middle layer, etc., it is reliably held by the branch portions 12, and the deterioration inhibitor 13 can be prevented from falling off the filter without using a binder or the like.

[0060] Furthermore, elemental analysis was performed on the surface of calcium oxide, which is a deterioration inhibitor and has been deposited with platinum. As a result, potassium derived from potassium hydrogen tartrate, which is water-soluble, was detected, confirming that it was attached to the calcium oxide powder. Elemental analysis was also performed on the surface of the platinum-deposited fiber. As a result, potassium (K) derived from potassium hydrogen tartrate was also detected, confirming the presence of the deterioration inhibitor in the fiber. This suggests that the deterioration inhibitor permeates the fiber, further inhibiting the deterioration of edible oil.

[0061] 3 is a schematic diagram showing an example of a cooking oil filter device to which the cooking oil degradation suppression filter according to this embodiment can be applied. The filter device 25 includes an oil tank 21 in which cooking oil 20 is stored, an annular pipe 22 through which the cooking oil 20 flows, a pump 24 for delivering the cooking oil 20, and a treatment section 23 equipped with a cooking oil degradation suppression filter that filters the cooking oil 20 and suppresses oxidative degradation. The oil tank 21, the pump 24, and the treatment section 23 are connected in series by the annular pipe 22.

[0062] In the filtering device 25 configured in this manner, the cooking oil 20 in the oil tank 21 is pumped through the piping 22 by the pump 24, filtered and subjected to oxidation degradation control in the processing unit 23, and then returned to the oil tank 21. Used cooking oil 20 contains impurities such as fried food residue and has also been subjected to oxidation degradation, but by passing through the cooking oil degradation control filter in the processing unit 23, impurities such as fried food residue are filtered out and oxidation degradation of the cooking oil 20 is controlled, slowing down the oxidation rate.

[0063] By treating the cooking oil 20 while circulating it as described above, the cooking oil 20 after use in cooking, etc., can be continuously treated. Furthermore, for example, by connecting a pipe 22 equipped with a pump 24 and a treatment unit 23 to the oil tank of a fryer for deep-frying foods, the cooking oil 20 being used for cooking can be treated in parallel with the cooking. If the oxidative degradation prevention performance of the cooking oil degradation prevention filter decreases, if the filterability decreases, or if it becomes clogged and no longer allows liquid to pass through, the cooking oil degradation prevention filter in the treatment unit 23 is replaced with a new one. Furthermore, a regular fried food debris collection filter or the like can be further installed in front of the cooking oil degradation prevention filter in the flow path.

[0064] The cooking oil deterioration prevention filter according to this embodiment is not limited to application to the above-described filtering device 25, but can be applied to various filtering devices and filters.

[0065] Test Example 2 (Example 1) Cellulose fiber was used as the natural fiber, calcium tartrate and potassium hydrogen tartrate were used as the degradation inhibitors, and activated carbon was used as the adsorbent. These were placed in water and beaten in a mixer. The calcium oxide, potassium hydrogen tartrate, activated carbon, and cellulose fiber accounted for 10% by mass, 10% by mass, and 70% by mass, respectively, based on the total mass of the materials other than water. The mixture was then dehydrated by filtration and dried to obtain a cooking oil degradation inhibitor filter according to this example.

[0066] A disk having a diameter of 90 mm and a thickness of 2.8 mm was cut from the prepared cooking oil degradation prevention filter to serve as test piece A. The density of test piece A was 0.28 g / cm ３ It was.

[0067] (Example 2) A disk having a diameter of 90 mm and a thickness of 0.6 mm was cut from the same cooking oil degradation prevention filter as in Example 1 to serve as test piece B. The density of test piece B was 0.43 g / cm ３ It was.

[0068] (Comparative Example) A disk having a diameter of 90 mm and a thickness of 1.0 mm was cut from cellulose filter paper to prepare a test piece C. The density of the test piece C was 0.38 g / cm ３ It was.

[0069] (Oxidation Deterioration Inhibition Test) An oxidation deterioration inhibition test was carried out using test pieces A to C. For the test, a filtration device 25 shown in FIG.

[0070] That is, one of the filters, test pieces A to C, was loaded into the processing section 23 of the filtration device 25, and 4 L of commercially available rapeseed oil was placed in the oil tank 21 as the edible oil 20. The oil was maintained at 180°C and circulated by pump 24, and filtered through the filters (test pieces A to C) in the processing section 23. The oil in the oil tank was maintained at 180°C. After 80 hours, the edible oil 20 was sampled and its acid value was measured. The acid value of the edible oil 20 was measured using potentiometric titration (end point: pH 12) in accordance with JIS K2501. The results are shown below. The oxidation inhibition performance is shown as a relative value, with the acid value of the comparative example being 1.

[0071]

[0072] As described above, it can be seen that the cooking oil degradation prevention filter according to the present invention has significantly better oxidation prevention performance than the filter made of fibers alone.

[0073] Although various embodiments have been described above with reference to the drawings, it goes without saying that the present invention is not limited to such examples. It is clear that a person skilled in the art can conceive of various modifications or alterations within the scope of the claims, and it is understood that these also naturally fall within the technical scope of the present invention. Furthermore, the components of the above-described embodiments may be combined in any manner without departing from the spirit of the invention.

[0074] This application is based on a Japanese patent application filed on July 26, 2021 (Patent Application No. 2021-121669), a Japanese patent application filed on November 24, 2021 (Patent Application No. 2021-190490), and a Japanese patent application filed on November 24, 2021 (Patent Application No. 2021-190491), the contents of which are incorporated by reference into this application.

[0075] REFERENCE SIGNS LIST 10 Fiber (cotton fiber) 11 Stem portion 12 Branch portion 13 Deterioration inhibitor 20 Cooking oil 21 Oil tank 22 Piping 23 Processing unit 24 Pump 25 Filtration device

Claims

1. A cellulose fiber and, A deterioration inhibitor containing at least an alkaline earth metal oxide, having, The mass of the deterioration inhibitor with respect to the total mass of the filter is 1% by mass or more and 50% by mass or less, The thickness is 0.6 mm or more and 2.8 mm or less, An edible oil deterioration inhibiting filter having a density of 0.28 g / cm3 or more and 0.43 g / cm3 or less.

2. Further, the edible oil deterioration inhibiting filter according to claim 1, which has a hydration reaction retarder composed of a sugar alcohol.

3. The sugar alcohol is at least one selected from erythritol, glycerin, lactitol, maltitol, mannitol, xylitol, and sorbitol. The edible oil deterioration inhibiting filter according to claim 2.

4. The sugar alcohol is either one or both of glycerin and sorbitol. The edible oil deterioration inhibiting filter according to claim 3.

5. The molecular weight of the sugar alcohol is 500 or less. The edible oil deterioration inhibiting filter according to claim 2.

6. Further, the edible oil deterioration inhibiting filter according to claim 1, which has at least one hydration reaction retarder selected from organic acid salts, sulfates, monosaccharides, and disaccharides.

7. The hydration reaction retarder contains at least one selected from citric acid, calcium sulfate, and sucrose. The edible oil deterioration inhibiting filter according to claim 6.

8. The molecular weight of the hydration reaction retarder is 500 or less. The edible oil deterioration inhibiting filter according to claim 6.

9. The edible oil deterioration inhibiting filter according to claim 2, which contains a trace amount of the hydration reaction retarder.

10. The edible oil deterioration inhibiting filter according to claim 9, which contains 10 ppm or more of the hydration reaction retarder per 1 g of the edible oil deterioration inhibiting filter.

11. The cellulose fiber contains beaten fibers. The edible oil deterioration inhibiting filter according to claim 1.

12. The cellulose fiber has a stem portion and a branched portion branched from the stem portion by beating, The edible oil deterioration inhibiting filter according to claim 11, wherein the branched portion holds particles containing the deterioration inhibitor.

13. The cellulose fiber is either one or both of natural fiber and artificial fiber. The edible oil deterioration inhibiting filter according to claim 11.

14. The artificial fiber is either one or both of a regenerated fiber and a synthetic resin fiber. The edible oil deterioration inhibiting filter according to claim 13.

15. The edible oil deterioration inhibitor is present both inside and on the surface of the cellulose fiber, and the edible oil deterioration inhibiting filter according to claim 1.

16. Furthermore, the edible oil deterioration inhibiting filter according to claim 1, further comprising an adsorbent.

17. The adsorbent contains at least one selected from silicon dioxide, natural clay, synthetic clay, and activated carbon, and the edible oil deterioration inhibiting filter according to claim 16.

18. A method for manufacturing the edible oil deterioration inhibiting filter according to any one of claims 1 to 17, a step of obtaining a suspension containing the cellulose fiber and the deterioration inhibitor; a step of dewatering and drying the suspension; and a method for manufacturing an edible oil deterioration inhibiting filter having the above steps.