Eel processing method

Abstract

To provide: an eel processing method in which, after eel is cooked and then temperature of the processed eel decreases, collagen contained in eel skin in the processed eel is less likely to harden; and a processed eel.SOLUTION: An eel processing method according to the present invention includes: a pre-broiling step of broiling a filleted eel; a boiling step of boiling the broiled eel at a temperature of collagen to be heat-denatured for 5 to 50 minutes; and a full-broiling step of broiling the boiled eel.

Description

Technical Field

[0001] The present invention relates to a method for processing eels and eels processed by this method. More specifically, the present invention relates to a method for processing grilled eels including a step of boiling eels and eels processed by this method.

Background Art

[0002] Currently, the processing methods (cooking methods) for grilled eels are roughly divided into a method of opening raw eels and steaming them in a steamer for several tens of minutes (Kanto style: Edo steaming) and a method of opening raw eels and directly grilling them over gas or charcoal (Kansai style), which are the mainstream.

[0003] The specific processing method for grilled eels is as follows. An eel that has been split open (back or belly) and subjected to a splitting process is skewered, and the skewered eel is grilled over charcoal until the fire passes through and the skin has fine wrinkles to make it a white grilled eel. The white grilled eel is steamed (Kanto style) or not steamed (Kansai style) and marinated in sauce, taken out of the sauce and grilled to make a grilled eel (Patent Document 1, last line of column 1 to line 6 of column 2).

[0004] Non-Patent Document 1 also describes a processing method similar to that of Patent Document 1 (pages 202 to 206). In addition, Non-Patent Document 1 states that eels contain a large amount of collagen, and when heated, the collagen changes into gelatin. Therefore, the higher the collagen content, the softer and juicier it becomes (3 lines from the bottom of page 204 to line 1 of page 205).

[0005] As a processing method for eels, "Goroemon steaming" is known. "Goroemon steaming" is a cooking method in which eels are boiled for a short time (less than 3 to 5 minutes) and then grilled.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Non-Patent Documents

[0007] [Non-Patent Document 1] Katsumi Tsukamoto, "The Science of Eels", Asakura Shoten, published in June 2019 [Summary of the Invention] [Problems to be Solved by the Invention]

[0008] When eating processed eels such as grilled eel immediately after cooking in a restaurant, the hardness due to the eel's skin (collagen on the skin surface) is not a concern. However, in the case of takeout or delivery, after heat cooking, when a certain amount of time (for example, 30 minutes or more) has passed, the temperature of the processed eel such as grilled eel drops to room temperature, the entire skin becomes hard, and the collagen contained in the skin also hardens, deteriorating the texture. Furthermore, when the processed eel is stored in the refrigerator, the skin may become so hard that it is difficult to chew.

[0009] Therefore, an object of the present invention is to provide a method for processing eels and processed eels in which the skin of the eel does not easily become hard even when the temperature of the heat-cooked processed eel drops. [Means for Solving the Problems]

[0010] Examples of aspects of the present invention are as follows. (Example Aspect 1) A method for processing eels, comprising: A pre-roasting step of roasting the dressed eel, and A boiling step of boiling the eel roasted in the pre-roasting step for a predetermined time until the collagen is irreversibly denatured. (Example Aspect 2) The method for processing eels according to Example Aspect 1, wherein The predetermined time in the boiling step is 5 minutes to 50 minutes. (Example Aspect 3) The method for processing eels according to Example Aspect 1, wherein The predetermined time in the boiling step is 10 minutes to 45 minutes.

[0011] (Embodiment Example 4) The method for processing eel according to Embodiment Example 1, wherein in the boiling step, the eel is boiled using the boiling dashi, the method for processing eel. (Embodiment Example 5) The method for processing eel according to Embodiment Example 1, wherein the eel is an eel skewered on a skewer, the method for processing eel. (Embodiment Example 6) The method for processing eel according to Embodiment Example 1, wherein it includes a main grilling step of grilling the eel boiled in the boiling step, the method for processing eel.

[0012] (Embodiment Example 7) The method for processing eel according to Embodiment Example 6, wherein in the main grilling step, the eel is grilled with sauce or without sauce, the method for processing eel. (Embodiment Example 8) The method for processing eel according to Embodiment Example 1, wherein before the pre - grilling step, it includes a butchering step of butchering the eel, the method for processing eel. (Embodiment Example 9) The boiled eel having an average weighted value (skin side) of 1.00 N or less by a penetration test for the boiled eel.

[0013] (Embodiment Example 10) In the boiled eel according to Embodiment Example 9, the boiled eel having an average weighted value (flesh side) of 0.40 N or less by a penetration test for the boiled eel. (Embodiment Example 11) In the boiled eel according to Embodiment Example 9, the boiled eel includes irreversibly denatured collagen, the boiled eel. (Embodiment Example 12) The kabayaki of eel obtained by making the boiled eel according to any one of Embodiments Examples 9 to 11 into kabayaki. [Advantages of the Invention]

[0014] The eel processing method of the present invention can provide an eel with excellent texture, in which the skin of the eel does not harden even when the temperature drops after processing.

Brief Description of the Drawings

[0015]

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Modes for Carrying Out the Invention

[0016] The eel processing method and the processed eel according to the embodiment of the present invention will be described. In the following embodiments, the processing method of grilled eel in the Kanto style (with bottom grilling) will be described as an example, but it is not limited thereto, and the processing method of grilled eel in the Kansai style (without bottom grilling) can also be used.

[0017] <Gutting step: Gutting a live eel> First, in the gutting step, a live eel (katsuman: live eel) is gutted with a kitchen knife and the body is cut into 2 to 4 equal parts (the number of cuts varies depending on the size of the eel). 3 to 5 bamboo skewers are inserted into the cut body.

[0018] <Grilling process: Grilling the eel that has been dressed> In the grilling process (the white grilling process), the dressed eel skewered on a bamboo skewer is placed on a grilling stand and grilled over charcoal or gas for about 3 to 15 minutes. In the grilling process, the eel is grilled without adding flavor. The grilling temperature is preferably 600°C to 750°C. Remove the eel from the grilling stand and arrange it, and remove the rough heat from the grilled eel.

[0019] <Boiling process: Boiling the grilled eel placed in a pot> The boiling process will be described. Fill a pot (for example, with a diameter of 40 to 60 cm and a capacity of 20 to 50 L) with water up to seven-tenths and boil it until it boils. Put the grilled eel skewered on skewers into the pot all at once in an amount that fills the surface of the pot.

[0020] After putting the eel into the pot, cover the pot and bring the boiling soup in the pot (preferably the dashi soup) to a boil. Boil the eel for a predetermined time after it starts boiling. The predetermined time can preferably be 5 to 50 minutes, more preferably 10 to 45 minutes, and even more preferably 16 to 22 minutes. The predetermined time varies depending on the type and size of the eel.

[0021] The boiling soup used was made by boiling water with kelp and sugar in a cooking pot for 2 to 3 days. The surface temperature of the boiling soup was 95°C to 99°C, and the central temperature of the put-in eel was 75°C to 90°C. The salt concentration of the boiling soup was 0.3% or less (the lowest value of the measuring instrument. No salt was added).

[0022] After the predetermined time has passed, since the boiled eel has become sufficiently soft, take out the eel from the hot water with a spatula so that the eel flesh does not fall off. Check the elasticity by pressing with a finger to see if the central part of the skin surface of the eel has become soft. When it is confirmed that the elasticity of the central part of the skin surface has become loose, lift it out of the pot.

[0023] <Final grilling process> Take out the boiled eel from the pot, turn off the hot water, and grill it again over a charcoal or gas grilling stand for 3 to 15 minutes. At this time, if it is grilled eel, add the sauce and grill it. When it is grilled, it is completed.

[0024] <Examination>

[0025]

[0026] <Differences from Conventional Examples, Features and Merits of this Embodiment>

[0027] In contrast, the eel processing method according to this embodiment includes a step of boiling the eel for a predetermined time of, for example, 20 minutes or more. By the step of boiling for a predetermined time, the uneven heating like baking is eliminated from the collagen (gelatinous substance) between the skin surface and the body, and uniform heating can be achieved, so that when eaten, the body and skin of the eel become soft enough to melt smoothly. Furthermore, in the case of eel steamed with steam as in the conventional method, after the grilling step, the skin is soft for 20 to 30 minutes, but when the time elapses and the temperature drops to room temperature, the skin becomes hard. In contrast, in the eel processing method "Yabe Etaemon Steaming" according to this embodiment, even when the time elapses and the temperature drops, as shown in the examples, the skin surface continues to maintain softness, so it can be used for takeout or eating outside the store.

[0028] In the conventional eel processing method including a steaming step with steam, even after the grilling step, the peculiar smell of eel (the collagen between the skin and the inside of the skin, the smell of fat) inevitably remains. In contrast, in the eel processing method "Yabe Etaemon Steaming" according to this embodiment, the peculiar smell of eel has almost disappeared.

[0029] In the conventional steaming step with steam, in order to confirm whether the heat has been transferred to the body of the eel, it is necessary to open the lid of the steamer, and since the height of the basket stage and the steam temperature and amount are different even in the baskets on the same stage, unevenness is likely to occur. In contrast, in the eel processing method "Yabe Etaemon Steaming" according to this embodiment, by opening the lid of the pot, it is possible to visually confirm and touch with a finger the state of heat transfer to each slice of eel to check its softness.

[0030] The effects and functions of the eel processing method of this embodiment are summarized as follows. · The body is easily loosened, the skin becomes soft, and the peculiar smell of fat unique to eel is no longer felt. · Even in the case of eel with a lot of fat, the extra fat content drops during the boiling process, resulting in a refreshing and non-greasy taste. · Even when it cools down, the body does not harden and remains soft and bouncy.

[0031] By using the eel processing method (Happae Goroemon steaming method) according to this embodiment, it is possible to provide eel that remains soft even when cooled to room temperature. As a result, new value is created for eel kabayaki products that have low evaluations in refrigerated and frozen products, which will also have a positive impact on the sales of the entire eel industry.

Example

[0032] Regarding the eel obtained by the eel processing method of this embodiment, it was confirmed by experiment whether the skin and the elasticity of the skin surface of the eel kabayaki remain soft even at room temperature. In addition to comparing with other steaming cooking methods, the superiority of the eel processing method according to this embodiment was confirmed by comparing with the conventional Goroemon steaming method with a short boiling time.

[0033] <Test target sample> Regarding the following Comparative Example A, Comparative Example B, and Example C, the hardness was measured. Comparative Example A (Edo steaming) is a grilled eel that has been opened and subjected to a searing process and a 10-minute steaming process as has been conventionally done. The searing process was performed under the same conditions for Comparative Example A, Comparative Example B, and Example C. Specifically, in the searing process, searing was performed for a total of 2 minutes at 550 - 650°C charcoal fire, 1 minute on the side of the flesh and 1 minute on the skin side.

[0034] Comparative Example B (Goroemon steaming) is a grilled eel that has been opened and subjected to a searing process and a boiling process. The boiling time in the boiling process was 2 minutes and 15 seconds. Example C (Happae Goroemon steaming) is a grilled eel processed by the processing method of this embodiment, and the boiling time in the boiling process was 18 minutes and 40 seconds.

[0035] Regarding each of the eels of Comparative Example A, B, and Example C, measurement samples were prepared as follows. For each of the above eels, four blocks each with a size of approximately 30 mm square were cut out from the head side (Figure 1) and used as measurement samples (identification symbols: Al, A2, Bl, B2). Also, for each of the above eels, measurement samples (identification symbols: A3, A4, B3, B4) were cut out in the same manner from the tail side. Each of the above eels was tested in a state of being at room temperature.

[0036] <Hardness measurement test> For the hardness measurement test, a penetration test was conducted using a creep testing machine (RHEONERII RE2-33005C: Yamaden Co., Ltd.). In the penetration test, a cylindrical plunger (diameter: 2 mm) was penetrated vertically from the side of each measurement sample under the conditions of using a 20 N load cell, a measurement speed of 10 mm / sec, and a strain rate of 170% (a stage movement distance 1.7 times the thickness of the measurement sample), and the load value was measured. When performing multiple measurements within the same block, the penetration site of the plunger was changed. The state of the penetration test by the creep testing machine is shown in Fig. 2.

[0037] <Test results> The load-displacement curve of Comparative Example A "Edo steamed (head side)" is shown in Fig. 3. Also, the load values at the peak tops of the side and skin side are shown in Table 1. For "Edo steamed (head side)-1" shown in Table 1, the average thickness was 11.0 mm, the average peak top load (side) was 0.51 N, and the average peak top load (skin side) was 1.68 N. For "Edo steamed (head side)-2" shown in Table 1, the average thickness was 10.8 mm, the average peak top load (side) was 0.54 N, and the average peak top load (skin side) was 1.25 N.

[0038] The peak top load is the value immediately before the plunger penetrates the body or skin, and it can be understood that the greater the peak top load, the harder it is. Therefore, the smaller the value of the peak top load, the softer the texture.

[0039]

Table 1

[0040] The load - distortion curves of Comparative Example A "Edo - style steaming (tail side)" are shown in Fig. 4. Also, the load values at the peak tops on the inner side and the skin side are shown in Table 2. For "Edo - style steaming (tail side) - 1" shown in Table 2, the average thickness was 11.0 mm, the average load at the peak top on the inner side was 0.63 N, and the average load at the peak top on the skin side was 1.59 N. For "Edo - style steaming (head side) - 2" shown in Table 2, the average thickness was 11.0 mm, the average load at the peak top on the inner side was 0.67 N, and the average load at the peak top on the skin side was 1.33 N.

[0041]

Table 2

[0042] The load - distortion curves of Comparative Example A "Edo - style steaming (head side)" are shown in Fig. 5. Also, the load values at the peak tops on the inner side and the skin side are shown in Table 3. For "Goroemon - style steaming (head side) - 1" shown in Table 3, the average thickness was 11.2 mm, the average load at the peak top on the inner side was 0.63 N, and the average load at the peak top on the skin side was 1.59 N. For "Goroemon - style steaming (head side) - 2" shown in Table 3, the average thickness was 12.1 mm, the average load at the peak top on the inner side was 0.67 N, and the average load at the peak top on the skin side was 1.33 N.

[0043]

Table 3

[0044] The load - distortion curves of Comparative Example B "Goroemon - style steaming (tail side)" are shown in Fig. 6. Also, the load values at the peak tops on the inner side and the skin side are shown in Table 4. For "Goroemon - style steaming (tail side) - 1" shown in Table 4, the average thickness was 11.1 mm, the average load at the peak top on the inner side was 0.70 N, and the average load at the peak top on the skin side was 2.70 N. For "Goroemon - style steaming (tail side) - 2" shown in Table 4, the average thickness was 10.6 mm, the average load at the peak top on the inner side was 0.81 N, and the average load at the peak top on the skin side was 3.04 N.

[0045]

Table 4

[0046] The load - distortion curve of Example C "Hachibe Goroemon Steamed (head side)" is shown in Fig. 7. Also, the load values at the peak tops on the body side and the skin side are shown in Table 5. For "Hachibe Goroemon Steamed (head side) - 1" shown in Table 5, the average thickness was 11.3 mm, the average peak load (body side) was 0.35 N, and the average peak load (skin side) was 0.74 N. For "Hachibe Goroemon Steamed (head side) - 2" shown in Table 5, the average thickness was 10.6 mm, the average peak load (body side) was 0.39 N, and the average peak load (skin side) was 0.90 N.

[0047]

Table 5

[0048] The load - distortion curve of Example C "Hachibe Goroemon Steamed (tail side)" is shown in Fig. 8. Also, the load values at the peak tops on the body side and the skin side are shown in Table 6. For "Hachibe Goroemon Steamed (tail side) - 1" shown in Table 6, the average thickness was 10.4 mm, the average peak load (body side) was 0.30 N, and the average peak load (skin side) was 0.60 N. For "Hachibe Goroemon Steamed (tail side) - 2" shown in Table 6, the average thickness was 10.8 mm, the average peak load (body side) was 0.39 N, and the average peak load (skin side) was 0.74 N.

[0049]

Table 6

[0050] <Summary> Table 7 summarizes the average values of Tables 1 to 6. As is clear from Table 7, it can be understood that the average load value of Example C is significantly lower than that of Comparative Examples A and B. Based on Example C, the eel obtained by the eel processing method according to this embodiment has an average load value (skin side) of 1.00 or less, preferably in the range of 0.90 to 0.70, and an average load value (flesh side) of 0.40 or less, preferably in the range of 0.40 to 0.30.

[0051]

Table 7

Claims

1. A method for processing eels, including a pre-baking step of baking the dressed eels, and a boiling step of boiling the eels baked in the pre-baking step for a predetermined time until the collagen is irreversibly denatured. A method for processing eels.

2. The method for processing eels according to Claim 1, wherein the predetermined time in the boiling step is 5 to 50 minutes. A method for processing eels.

3. The method for processing eels according to Claim 1, wherein the predetermined time in the boiling step is 10 to 45 minutes. A method for processing eels.

4. The method for processing eels according to Claim 1, wherein in the boiling step, the eels are boiled using the boiled dashi. A method for processing eels.

5. The method for processing eels according to Claim 1, wherein the eels are eels skewered on a stick. A method for processing eels.

6. The method for processing eels according to Claim 1, further including a main baking step of baking the eels boiled in the boiling step. A method for processing eels.

7. The method for processing eels according to Claim 6, wherein in the main baking step, the eels are baked with or without sauce. A method for processing eels.

8. The method for processing eels according to Claim 1, further including a dressing step of dressing the eels before the pre-baking step. A method for processing eels.

9. Boiled eels having an average penetration value (skin side) of 1.00 N or less in a penetration test for the boiled eels.

10. In the boiled eel according to claim 9, The boiled eel, wherein an average weighted value (side of the body) by a penetration test on the boiled eel is 0.40 N or less.

11. In the boiled eel according to claim 9, The boiled eel, wherein the boiled eel comprises irreversibly denatured collagen.

12. Grilled eel obtained by grilling the boiled eel according to any one of claims 9 to 11.

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