JP7326992B2 - Oil deterioration suppression filter - Google Patents

Description

TECHNICAL FIELD The present invention relates to a filter that suppresses deterioration of oil, and more particularly to a technique effectively applied to a filter that suppresses deterioration of cooking oil.

Edible oil (hereinafter also simply referred to as "oil") is used in various foods, but it deteriorates due to heating associated with cooking such as tempura and frying, or left unattended, and deteriorates the taste, smell, and appearance of food. Let In some cases, deterioration of edible oil may cause food poisoning. Therefore, it is necessary to appropriately judge the degree of deterioration by using indices such as acid value and peroxide value, and to replace the cooking oil with new edible oil at an appropriate timing.

However, at delicatessen stores where tempura, fried foods, etc. are prepared, or at supermarkets' delicatessen counters, the shorter the replacement cycle, the more the deterioration of the cooking oil can be prevented, but there is the problem that the prices of the prepared foodstuffs after cooking will rise. . Edible oil that has deteriorated beyond a predetermined standard is discarded, but from the viewpoint of global environmental conservation, there is concern about the impact of the discarded oil on the environment. Therefore, it is desired to delay the deterioration of edible oil as much as possible, thereby prolonging the oil replacement cycle and reducing the number of times the oil is discarded.

As a technique for suppressing such deterioration of edible oil, a method for regenerating edible oil using a filter as described in Patent Document 1, for example, has been proposed. FIG. 8 shows a filtering device 101 using the filter 111 described in Patent Document 1. As shown in FIG. The used cooking oil stored in the fryer 102 is sent to the oil tank 108 through the first liquid sending pipe 104 and filtered through the filtering section 110 .

The filtering section 110 includes a regeneration filter 111 and a metal mesh 120 . After passing through the filtering unit 110 , the oil accumulated in the lower part of the oil tank 108 is sent to the circulation pump 103 through the second liquid sending pipe 105 . After the oil exiting the circulation pump 103 passes through the valve 109 , one side passes through the third liquid-sending pipe 106 to the oil tank 108 , and the other passes through the fourth liquid-sending pipe 107 to the fryer 102 . It is explained that regardless of which route is taken, the oil is filtered by the filtering section 110 including the filter 111, and the used oil is regenerated.

9(a) is a plan view of the filter 111 used in the filtering device 101 shown in FIG. 8, and FIG. 9(b) is a sectional view of FIG. 9(a). The filter 111 is composed of a bag-like resin fiber sheet 114 formed by sealing the peripheral portions of the two fiber sheets 113 and 113, and a particle filling portion 112 filled with composite oxide particles.

However, when such a filter 111 is used, the size of the pores (gaps between fibers) in the fiber sheets 113, 113 is adjusted to prevent the composite oxide particles from flowing out of the bag-shaped resin fiber sheet 114. It is necessary to keep the particle size smaller than that of the composite oxide particles contained in the . The smaller the size of the pores, the more the complex oxide particles in the bag can be prevented from flowing out to the outside, but clogging occurs when oil residue or the like that has passed through the metal mesh 120 adheres to the bag. Or, it is conceivable that since the pores are small, the passage speed of the oil is lowered, and the filtration speed is lowered.

Patent document 2 discloses an edible oil purifying filter in which an edible oil deterioration inhibitor is sandwiched between sheets having a filter action. However, since the deterioration inhibitor is carried in the filter, the pores of the filter are smaller than the particle size of the additive. As a result, there is a possibility that clogging may occur when oil scum or the like passes through, or that the passage speed of oil may decrease due to small pores, or the filtration speed may decrease.

JP 2006-088039 A JP 2018-002977 A

SUMMARY OF THE INVENTION It is an object of the present invention to provide an edible oil filter that can prevent the stored degradation inhibitor from flowing out and has good oil filterability. With the goal.

The above objects of the present invention are achieved by the following configurations.
(1); A deterioration suppressing agent that suppresses deterioration of oil and a filter body composed of a pair of sheets sandwiching the deterioration suppressing agent therebetween. A filter comprising a closing portion and an oil passage hole for allowing oil to pass through.
(2); The filter according to (1) above, wherein the size of the oil passage hole is larger than the size of the pores of the filter body.
(3); The filter according to (2) above, wherein the filter main body is made of a papermaking sheet, and the size of the oil passage hole is larger than the size of the pores of the papermaking sheet.
(4); The filter according to (2) above, wherein the filter body is made of a nonwoven fabric sheet, and the size of the oil passage holes is larger than the size of the pores of the nonwoven fabric sheet.
(5); The filter according to any one of (1) to (4) above, wherein the size of the oil passage hole is larger than the particle size of the deterioration inhibitor.
(6); the closing portion has a closing edge portion that closes the periphery of the deterioration inhibitor, and a bag portion that is surrounded by the closing edge portion and stores the deterioration inhibitor, and the oil passage hole corresponds to the deterioration inhibitor; The filter according to any one of (1) to (5) above, which is formed on the closed edge.
(7); The filter according to any one of (1) to (6) above, wherein a second filter for physical filtration is superimposed on at least one of the pair of sheets of the filter body.

ADVANTAGE OF THE INVENTION According to this invention, while being able to prevent the deterioration inhibitor accommodated from flowing out to the exterior, the filter for oil with the favorable filterability of oil can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure explaining the filtering apparatus of the edible oil to which the filter for edible oils of this invention is applied. 1A and 1B are an exploded perspective view and a perspective view of a first embodiment of a filter according to the present invention; FIG. (a) is a plan view of the first embodiment, and (b) is a sectional view taken along line AA of (a). Fig. 3 is a plan view of a second embodiment of a filter according to the invention; Fig. 3 is a plan view of a third embodiment of a filter according to the invention; FIG. 5 is a plan view of a fourth embodiment of a filter according to the invention; FIG. 5 is a cross-sectional view of a fifth embodiment of a filter according to the invention; It is a figure explaining an example of the filtering apparatus of the conventional edible oil. 9A and 9B are a plan view and a cross-sectional view of a filter used in the filtering device of FIG. 8; 1 is a plan view of a first embodiment of a filter according to the invention; FIG. Fig. 4 is a plan view of a second embodiment of a filter according to the invention; Fig. 4 is a plan view of a third embodiment of a filter according to the invention; FIG. 5 is a plan view of a fourth embodiment of a filter according to the invention; FIG. 5 is a plan view of a fifth embodiment of a filter according to the invention; FIG. 6 is a plan view of a sixth embodiment of a filter according to the invention; FIG. 8 is a plan view of a seventh embodiment of a filter according to the invention; FIG. 11 is a plan view of an eighth embodiment of a filter according to the invention;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
<First embodiment>
FIG. 1 shows an edible oil filtering apparatus to which the filter according to the present invention is applied. The filtering device 1 includes a fryer 2 for storing cooking oil, a pump 3 for circulating the cooking oil stored in the fryer 2 within the filtering device 1, and a filter 11 for filtering the cooking oil sent out from the pump 3. have. A first oil passage 4 connects between the fryer 2 and the pump 3, a second oil passage 5 connects between the pump 3 and the filter 11, and a third oil passage connects between the filter 11 and the fryer 2, A filter 11 according to the present invention is provided between the second oil passage 5 and the third oil passage 6 .

2 is an exploded perspective view and a perspective view of the filter 11, FIG. 3(a) is a plan view of the filter 11, and FIG. 3(b) is a sectional view taken along the line AA of FIG. 3(a). The filter in FIG. 3 shows a state in which the contour of the outer periphery of the filter in FIG. 2 is processed into a circular shape. The filter 11 has a deterioration suppressing agent 12 and a filter body 14 composed of a pair of sheets 13, 13 for sandwiching the deterioration suppressing agent 12 therebetween.
The deterioration suppressing agent 12 functions to suppress the deterioration of the cooking oil by coming into contact with the cooking oil. For example, potassium hydrogen tartrate and calcium oxide are used.

The filter body 14 is composed of a pair of sheets 13, 13 such as a papermaking sheet, a nonwoven fabric sheet, or a resin fiber sheet, or a pair of sheets 13, 13 obtained by appropriately combining these various sheets. A deterioration inhibitor 12 is sandwiched between them. The size of the interstices (pores) between the fibers constituting the papermaking sheet, the nonwoven fabric sheet, or the resin fiber sheet is determined so that the deterioration inhibitor 12 does not flow out from the sheets 13, 13 to the outside. smaller than the diameter.

Further, in order to prevent the degradation inhibitor 12 from flowing out of the filter body 14 while the cooking oil is being filtered by the edible oil filtering device 1, the periphery of the degradation inhibitor 12 is provided in the filter body 14. It is closed by a closing part 15 (see the cross-sectional view of FIG. 3(b)). The exploded perspective view of FIG. 2 shows a state before the filter 11 closes the deterioration suppressing agent 12 with the closing portion 15 . As a method for closing the periphery of the deterioration suppressing agent 12 with the closing portion 15, for example, the deterioration suppressing agent 12 is sandwiched in a single-sided heat-sealable nonwoven fabric, and heat is applied to perform heat fusion processing. Alternatively, ultrasonic welding may be used to form the closure. In the case of papermaking sheets, the closure may also be formed by interlocking and crimping the fibers of the paper.

The filter body 14 is further provided with a circular oil passage hole 16 . This oil passage hole 16 is preferably formed by punching with a punch after forming the above-described closing portion. However, the closing portion may be formed using a pair of sheets in which oil passage holes are formed in advance.
The perspective view of the filter 11 in FIG. 2 shows the state after closing and piercing. The size of this oil passage hole 16 is made larger than the size of the pores of the filter body 14 described above. This makes it easier for the cooking oil to pass through the oil passage hole 16 than through the degradation inhibitor 12 . The "size" in the case of the size of the oil passage hole or the size of the pores means the size of the area when viewed in a plan view.

When such a filter 11 is used in the edible oil filtering device 1 shown in FIG. will do. Strictly speaking, the oil passing through the oil passage hole 16 is not necessarily filtered. However, if the oil stored in the fryer 2 is circulated and passed through the filter 11 several times, by devising the shape of the oil passage hole as in the embodiment described later, the same part of the oil can be extracted each time. The probability of passing through the passage holes is remarkably reduced, and most of the edible oil is filtered by the deterioration suppressing agent 12 .

When the edible oil passes through the filter 11, the deterioration suppressing agent 12 is confined by the closing portion 15, so that it is prevented from flowing out of the filter body 14 to the outside.
Moreover, since the oil passage holes 16 through which the cooking oil can pass are formed, the filterability of the filter 11 is improved. The size of the pores of the filter body 14 is limited by the size of the deterioration inhibitor 12. Filterability of the filter 11 can be further improved.

<Second embodiment>
Next, a second embodiment will be described with reference to FIG. It should be noted that, in the following description, the same or similar reference numerals are assigned to the same configurations as in the first embodiment, and detailed description thereof will be omitted. FIG. 4 is a plan view of the filter 21, similar to FIG. 3(a).
The difference from the first embodiment is that the shape of the oil passage hole 26 is triangular. With such a shape, even if the number of oil passage holes 26 is the same, the amount of oil passing through the oil passage holes 26 is limited, and the oil filtered by the deterioration inhibitor 12 (see FIG. 2) is reduced. can be increased. As in the present embodiment, by devising the shape of the oil passage hole (for example, by mixing a circular hole and a triangular hole in a predetermined ratio, or by using another shape such as a rhombus hole), the oil can be The amount of oil that passes through the passage holes and the amount of oil that passes through the degradation inhibitor can be adjusted.

<Third Embodiment>
Next, a third embodiment will be described with reference to FIG. FIG. 5 is a plan view of the filter 31, similar to FIG. 3(a). In this embodiment, only one oil passage hole 36 is formed in the center of the filter body 33 . With such a configuration, the amount of oil passing through the oil passage hole 36 can be minimized, and the amount of oil filtered by the deterioration suppressing agent 12 (see FIG. 2) can be increased.

<Fourth Embodiment>
Next, a fourth embodiment will be described with reference to FIG. FIG. 6 is a plan view of the filter 41 similar to FIG. 3(a). In this embodiment, the closing portion 45 for confining the deterioration suppressing agent 12 (see FIG. 2) has a closing edge portion 45a and a bag portion 45b surrounded by the closing edge portion 45a and containing the deterioration suppressing agent 12. are doing.

As in each of the above-described embodiments, the closing portion 45 does not apply closing processing to the entire surface of the filter body 44, but only the closing edge portion 45a is closed (in the drawing, the closed portion is hatched for convenience). displayed). The closing edge portion 45a has a circular edge portion 45a1 extending in the circumferential direction on the peripheral edge portion of the filter body 44 and a straight edge portion 45a2 extending in a cross shape in the central portion of the filter body 44. As shown in FIG. Thereby, the bag portion 45b is divided into four regions 45b1, 45b2, 45b3, and 45b4.
The oil passage holes 46 are provided at predetermined intervals in the circular edge portion 45a1 and the straight edge portion 45a2. By adopting such a configuration, it is possible to reliably perform filtration by the deterioration suppressing agent 12 (see FIG. 2) accommodated in the bag portion 45b while securing the amount of oil passing through the filter 41. FIG.

<Fifth Embodiment>
Next, a fifth embodiment will be described with reference to FIG. FIG. 7 is a cross-sectional view of the filter 51 similar to FIG. 3(b). In this embodiment, the second filter 61 is superimposed above one sheet 13 of the filter main body 14 of the first filter 11, which is the filter described in the first embodiment. That is, the filter 51 according to the fifth embodiment includes the filter 11 of the first embodiment 1 as a first filter (first filter layer) 11A, and furthermore, one sheet of the filter main body 14 of the first filter 11A 13 with a second filter (second filter layer) 61 . The second filter 61 is made of a sheet of paper or non-woven fabric, and functions as a physical filter to eliminate oil scum and the like from passing through. Therefore, the second filter 61 is not provided with oil passage holes. The first filter 11A and the second filter 61 may be simply superimposed, or may be integrated by adhesion or the like.

With such a configuration, the second filter 61 performs physical filtration and the first filter 11A performs chemical filtration, so that the effect of suppressing deterioration of oil can be further improved. It should be noted that the second filter 61 may be superimposed not only above the first filter 11A but also above and below. That is, the second filter 61 may be sandwiched between the two first filters 11A. By doing so, when the filter 51 is attached to the edible oil filtering device 1 shown in FIG. physical filtration by the second filter 61 on the upstream side of filtration). Further, the first filter 11A is not limited to the structure described in the first embodiment, and filters described in the second to fourth embodiments may be used.

The present invention will be further described with reference to examples below, but the present invention is not limited by these examples.
[Sample preparation]
(Example 1, Comparative Example 1)
A filter having the shape shown in FIG. 10 was produced by the following method.
As a single-sided heat-sealable nonwoven fabric, "Precise α Seal (registered trademark)" manufactured by Asahi Kasei Co., Ltd., and as a deterioration inhibitor, a mixture of potassium hydrogen tartrate and calcium oxide at a mass ratio of 1:1 was prepared. Furthermore, as the nonwoven fabric (“Precisé α-Seal”), one having a thickness of 0.17 mm per sheet, a basis weight of 45 g/m ² , a porosity of 52 vol %, and a pore diameter of 55 μm was used. Porosity and pore diameter were measured with a mercury porosimeter using the principle of mercury porosimetry.

Pre-mixed deterioration inhibitor is sprinkled so that the basis weight is 30 g/m ² , sandwiched between the heat-sealed surfaces of the non-woven fabric (Precisé α-Seal), heat-sealed on the entire surface (heat-sealed on the entire surface), and then cut to Φ 90 mm. By doing so, Comparative Example 1 was obtained. Then, the filter 71 of Example 1 having holes (oil passage holes 16) was obtained by punching out φ8 mm from this with a punch. That is, the filter of Comparative Example 1 has a configuration "without oil passage holes", and the filter 71 of Example 1 has a configuration "with oil passage holes", as shown in FIG. The basic structure of the filter 71 of Embodiment 1 and the filter of Comparative Example 1 is substantially the same as that of the filter 11 of the first embodiment, except for the presence or absence of oil passage holes 16 . The filter 71 of Example 1 has only one oil passage hole 16 in the center like the oil passage hole 36 of the filter 31 (see FIG. 5) of the third embodiment described above.

(Examples 2-8)
Filters 72 to 78 of Examples 2 to 8 having different total hole areas of the oil passage holes 16 when viewed from above were obtained by changing the hole diameter and the number of holes according to Example 1 (Figs. 17 and Table 1). 11 is Example 2, the filter 73 of FIG. 12 is Example 3, the filter 74 of FIG. 13 is Example 4, the filter 75 of FIG. 14 is Example 5, The filter 76 in FIG. 15 is the sixth embodiment, the filter 77 in FIG. 16 is the seventh embodiment, and the filter 78 in FIG. 17 is the eighth embodiment.

(Example 9)
In order to sufficiently obtain the effect of suppressing oxidation deterioration, two sheets of the filter 75 of Example 5 (see FIG. 14) were stacked, and a PET non-woven fabric filter similar to the filter of Comparative Example 2 was further stacked on the upper layer. By further stacking the PET nonwoven fabric on the stack of two filters 75, it is possible to more effectively prevent clogging due to deterioration.

(Comparative example 2)
A 4 mm thick PET non-woven fabric filter was prepared to perform a physical function to exclude oil scum and the like from passing through. This PET nonwoven fabric has a basis weight of 340 g/m ² .

〔Evaluation test〕
The edible oil filtering apparatus 1 of FIG. 1 was used. A pressure gauge is installed before and after the filter 11 shown in FIG. 8L of "Nissin Canola Oil" manufactured by Nisshin OilliO Group Co., Ltd. was added as the oil. A filter holder with a diameter of 90 mm was installed at the position of the filter 11, and the pump was designed to constantly circulate the cooking oil.

・Filterability test (pressure loss test)
The filters 71 to 78 of Examples 1 to 9 were installed in the filter holder for each example, and the difference in pressure before and after the edible oil passed through was measured. The initial filterability was determined using the slope of the relationship between the flow rate and the pressure difference at a temperature of 100° C. as an index (the smaller the slope, the better the filterability). The filterability after the elapse of time was measured by constant circulation heating for 96 hours at a temperature of 180° C., and the pressure loss after 96 hours was used as an index. Relative values are shown in Table 1 with the measurement result of Comparative Example 1 set to 1.
Here, the edible oil in the fryer 2 is heated to 100° C., the flow rate is changed by changing the rotation speed of the pump 3, and the pressure difference before and after the edible oil passes is measured using two pressure gauges. By doing so, an approximation formula was derived, the slope was calculated, and the slope was used as an initial filterability index. Specifically, the slope a is obtained from an approximate straight line (y=ax) drawn by XY coordinates with the flow rate (L/min) as the X axis and the pressure difference (MPa) as the Y axis.

· Oxidation deterioration suppression test (Examples 5 and 9, Comparative Examples 1 and 2)
An edible oil of 180° C. was constantly heated and circulated, and the test was continued for 96 hours. As the degree of deterioration, the acid value, which is measured using a potentiometric titration method, was used as an index in accordance with JIS K 2501. The acid value after 96 hours was measured, and the relative value is shown in Table 1, with the result of Comparative Example 2 being 1. In Table 1, the percentage (%) described in the perforated configuration is calculated by the perforated area with respect to the entire filter area. Both the entire filter area and the holed area are ideal values.

[Results]
From the test results shown in Table 1, it is possible to obtain a filter with better filterability (initial and change over time) by performing hole processing as compared with Comparative Example 1. Moreover, in Examples 1 to 4, the filterability is improved more than that in Comparative Example 1 regardless of the drilling area. Furthermore, in Examples 1, 5 to 8, the filterability is improved regardless of the hole diameter. That is, it can be seen that there are no particular restrictions on the area and diameter of the oil passage holes when viewed in plan (Examples 1 to 9, Comparative Example 1).

Next, the effect of the deterioration inhibitor was confirmed. It can be seen that Examples 5 and 9 and Comparative Example 1 have an oxidative deterioration inhibitory effect compared to the filter (Comparative Example 2) that does not contain an oxidative deterioration inhibitor. From the above results, it was found that the filterability of the filter was improved by providing the holes, and a filter having an effect of suppressing oxidative deterioration was obtained. That is, it was possible to obtain a filter that can prevent the stored degradation inhibitor from flowing out to the outside, has good filterability for oil, and can suppress oxidative degradation of edible oil.
Further, by comparing the filter 75 of Example 5 and the filter of Example 9, it was found that the filter of Example 9 had better filterability and suppressed oxidation deterioration after 96 hours. That is, by increasing the amount of the oxidative degradation inhibitor, the effect of suppressing oxidative degradation is further obtained, and by stacking the PET nonwoven fabric, the filterability is improved over a long period of time.

It should be noted that the present invention is not limited to the above-described embodiments, and can be modified, improved, etc. as appropriate. For example, the shape and number of oil passage holes can be changed variously, and the number of filters to be used and how to combine a plurality of filters can be changed variously according to the application.
Further, the present invention is not limited to a filter that suppresses deterioration of cooking oil, but can be applied to filters that suppress deterioration of other oils.

Reference Signs List 11, 21, 31, 41, 51 filter 11A first filter 12 deterioration inhibitor 13, 33 sheet 14, 44 filter body 15, 45 closing portion 16, 26, 36, 46 oil passage hole 45a closing edge portion 45b bag portion 61 Second filter

Claims (3)

Having a deterioration suppressing agent for suppressing deterioration of oil and a filter body composed of a pair of sheets sandwiching the deterioration suppressing agent,
The filter body is provided with a closing portion for confining the deterioration suppressing agent and an oil passage hole for allowing oil to pass through ,
A filter , wherein the size of the oil passage hole is larger than the size of the pores of the filter body . 2. The filter according to claim 1 , wherein said filter body is made of a paper sheet, and said oil passage holes are larger in size than the pores of said paper sheet. 2. The filter according to claim 1 , wherein said filter body is made of a non-woven fabric sheet, and said oil passage holes are larger in size than the pores of said non-woven fabric sheet.

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