A method for improving water retention of golden pomfret

Abstract

The present invention provides a method for improving the water retention of golden pomfret. The method first bleeds unconscious fresh golden pomfret for 4 to 10 minutes, then soaks the fish in a polyphenol solution at a concentration of 100 to 200 mg / L for 8 to 12 minutes. Specifically, by combining two main processes—specific bleeding (blending during coma) and soaking in a polyphenol solution—and by specifically setting process parameters such as the bleeding time, polyphenol solution concentration, and soaking time, the process complements each other, synergistically improving the water retention of the golden pomfret and allowing it to maintain high edible quality even after prolonged frozen storage and transportation.

Description

Technical Field

[0001] The present invention belongs to the technical field of water retention of frozen golden pomfret, and more specifically relates to a method for improving the water retention of golden pomfret. Background Art

[0002] Golden pomfret, scientifically known as Trachinotus ovatus, is a major marine aquaculture species along my country's southern coast. Its delicious meat, rich in vitamins, minerals (such as selenium, iodine, and phosphorus), protein, and unsaturated fatty acids, is highly nutritious and popular among consumers. With the increasing scale of golden pomfret farming, it often requires prolonged freezing for storage and transportation. However, freezing causes the water in the fish to form ice crystals, which are lost during thawing, resulting in a reduced moisture content and a tougher texture. Therefore, there is an urgent need to find a method to improve the water retention of golden pomfret to ensure that it maintains a high edible quality even after prolonged storage and transportation. Summary of the Invention

[0003] The present invention aims to improve the water retention of golden pomfret by combining coma bleeding with polyphenol solution soaking and other processes to pre-treat the golden pomfret, thereby significantly improving its water retention and enabling it to maintain a high edible quality after long-term frozen storage and transportation in the later stage.

[0004] The above-mentioned purpose of the present invention is achieved through the following technical solutions:

[0005] The present invention provides a method for improving the water retention of golden pomfret, comprising the following steps:

[0006] S1. Bleed the unconscious fresh golden pomfret for 4-10 minutes;

[0007] S2. Soak the golden pomfret obtained in S1 in a polyphenol solution with a concentration of 100-200 mg / L for 8-12 minutes.

[0008] The present invention conducts a targeted exploration of the properties of golden pomfret, sequentially combining two main processes, namely a specific method of bleeding (coma bleeding) and a polyphenol solution soaking treatment, and specifically sets process parameters such as bleeding time, polyphenol solution concentration and soaking time. These links synergistically improve the water retention of golden pomfret, so that the fish can still maintain a high edible quality after long-term frozen storage and transportation in the later stage.

[0009] Preferably, the coma described in S1 is achieved by soaking the fresh golden pomfret in an ice-water mixture, and the amount of the ice-water mixture is sufficient to soak the fresh golden pomfret.

[0010] More preferably, the temperature of the ice-water mixture is 0-4°C.

[0011] Preferably, before the bleeding in S1, the fresh golden pomfret is unconscious for more than 5 minutes.

[0012] Preferably, before bleeding in S1, the unconscious fresh golden pomfret is cleaned.

[0013] Preferably, the bleeding in S1 is tail bleeding or spinal bleeding, most preferably tail bleeding.

[0014] Preferably, the bloodletting in S1 is also performed while hanging, which is more conducive to the outflow of blood.

[0015] Preferably, the bloodletting treatment in S1 lasts for 10 minutes.

[0016] Preferably, before the soaking in S2, the golden pomfret obtained in S1 is also cleaned to remove surface moisture.

[0017] Preferably, the polyphenol in S2 is one or more of tea polyphenols, chlorogenic acid, catechin, and gallic acid, and chlorogenic acid is most preferred.

[0018] Preferably, the concentration of the polyphenol solution in S2 is 100 mg / L. The amount of the polyphenol solution used is sufficient to soak the golden pomfret.

[0019] Preferably, the soaking time in S2 is 10 minutes.

[0020] The present invention has the following beneficial effects:

[0021] The present invention conducts a targeted exploration of the properties of golden pomfret, sequentially combining two main processes, namely a specific method of bleeding (coma bleeding) and a polyphenol solution soaking treatment, and specifically sets process parameters such as bleeding time, polyphenol solution concentration and soaking time. These links synergistically improve the water retention of golden pomfret, so that the fish can still maintain a high edible quality after long-term frozen storage and transportation in the later stage. DETAILED DESCRIPTION

[0022] The present invention is further described below with reference to specific examples, which, however, are not intended to limit the present invention in any way. Unless otherwise specified, the reagents, methods, and equipment used in the present invention are conventional reagents, methods, and equipment in the art.

[0023] Unless otherwise specified, the reagents and materials used in the following examples were commercially available.

[0024] 1. Test Method

[0025] Centrifugal loss rate: Take 5±0.3g of fish pieces (weighing W0), wipe off excess surface water with absorbent paper, place in a 50mL centrifuge tube, centrifuge at 4°C, 1000×g for 10 min, take out, wipe off excess surface water again with absorbent paper (weighing W1), and finally calculate the centrifugal loss rate using the formula "Centrifugal loss rate (%) = (W0-W1)W0×100%".

[0026] Cooking loss rate: Take 5±0.3g of fish pieces (weighing W0), wipe off excess surface moisture with absorbent paper, place them in a No. 5 cooking bag, heat them in a water bath (80℃, 10min), take them out, wipe off excess surface moisture again with absorbent paper (weighing W2), and finally calculate the cooking loss rate using the formula "Cooking loss rate (%) = (W0-W2)W0×100%".

[0027] Texture properties: The firmness, springiness, and chewiness of fish chunks were measured using a TA.XT plusC texture analyzer (Stable Micro Systems, London, England). A cylindrical probe (P / 0.5) was used. A 3 × 3 × 1 cm fish chunk was compressed in two cycles with a trigger force of 5 g. The compression rates before, during, and after the test were 3, 1, and 3 mm / s, respectively, and the compression strain was 50%.

[0028] Example 1 Treatment of Samples 1 to 4

[0029] 1. Sample processing

[0030] (1) Sample 1 (Golden Pomfret coma and bloodletting)

[0031] Wash fresh golden pomfret and soak it in a mixture of ice and water at 4°C. After the fish enters a coma, continue soaking for 5 minutes.

[0032] S2. Clean the golden pomfret and bleed its tail for 10 minutes while hanging the fish.

[0033] (2) Sample 2 (Golden Pomfret unconscious but not bled)

[0034] Same as product 1, except that S2 is not performed. The details are as follows:

[0035] Clean the fresh golden pomfret and soak it in a mixture of ice and water at 4°C. After the fish enters a coma, continue soaking for 5 minutes.

[0036] (3) Sample 3 (Golden Pomfret was not unconscious and bled)

[0037] Same as product 1, except that S1 is not performed. Details are as follows:

[0038] Clean the fresh golden pomfret, bleed the tail of the golden pomfret for 10 minutes, and hang the fish body while bleeding.

[0039] (4) Sample 4 (tilapia coma and bleeding)

[0040] Same as item 1, except that the golden pomfret is replaced with tilapia. Details are as follows:

[0041] Wash fresh tilapia and soak them in a mixture of ice and water at 4°C. After the fish enters a coma, continue soaking for 5 minutes.

[0042] S2. Wash the tilapia and bleed its tail for 10 minutes while hanging it.

[0043] 2. Sample testing

[0044] Samples 1-4 were cleaned, drained, and placed in food-grade packaging bags. The air inside the bags was vacuum-packed and sealed. The bags were then frozen and stored at -20°C for 30 days. After 30 days, the fish were removed and their cooking loss rates were measured. Fresh golden pomfret (untreated, not sterilized, bled, or frozen) served as a blank control. The results are shown in Table 1.

[0045] Table 1

[0046] Cooking loss rate (%) Sample 1 (Golden Pomfret coma and bloodletting) 16.15 Sample 2 (Golden Pomfret unconscious but not bled) 17.66 Sample 3 (Golden Pomfret bled without losing consciousness) 16.81 Sample 4 (tilapia coma and exsanguination) 16.94 Blank control (fresh golden pomfret) 16.71

[0047] From Table 1 we can see that:

[0048] (1) The cooking loss rate of sample 1 was lower than that of sample 2, indicating that bleeding treatment of golden pomfret can effectively improve the water retention of golden pomfret.

[0049] (2) The cooking loss rate of sample 1 was lower than that of sample 3, indicating that a specific bleeding method (i.e., coma bleeding) can effectively improve the water retention of golden pomfret.

[0050] (3) The cooking loss rate of sample 1 was lower than that of sample 4, indicating that the method of bleeding to improve the water retention of fish body is more suitable for golden pomfret.

[0051] (4) The cooking loss rates of samples 2 and 3 were higher than those of the blank control, indicating that either the coma treatment or the bleeding treatment alone would reduce the water retention of golden pomfret. However, sample 1, which used the method of first coma and then bleeding, reduced the cooking loss rate by 0.56% compared with the blank control, indicating that the water retention was actually improved. This indicates that the coma and bleeding processes in sample 1 played a synergistic role in improving the water retention of golden pomfret.

[0052] Example 2 Sample 5 (10 min bloodletting + immersion in 100 mg / L chlorogenic acid solution)

[0053] Wash fresh golden pomfret and soak it in a mixture of ice and water at 4°C. After the fish enters a coma, continue soaking for 5 minutes.

[0054] S2. Clean the golden pomfret and bleed its tail for 10 minutes while hanging the fish.

[0055] S3. Wash the golden pomfret and drain the surface water.

[0056] S4. Soak the golden pomfret in a 100 mg / L chlorogenic acid solution for 10 minutes.

[0057] Example 3 Sample 6 (10 min bloodletting + 200 mg / L chlorogenic acid solution soaking)

[0058] Same as Example 2, except that the concentration of S4 chlorogenic acid solution is 200 mg / L.

[0059] Wash fresh golden pomfret and soak it in a mixture of ice and water at 4°C. After the fish enters a coma, continue soaking for 5 minutes.

[0060] S2. Clean the golden pomfret and bleed its tail for 10 minutes while hanging the fish.

[0061] S3. Wash the golden pomfret and drain the surface water.

[0062] S4. Soak the golden pomfret in a 200 mg / L chlorogenic acid solution for 10 minutes.

[0063] Example 4 Sample 7 (4 min bloodletting + 200 mg / L chlorogenic acid solution immersion)

[0064] Same as Example 3, except that the tail bleeding time of S2 was 4 minutes.

[0065] Wash fresh golden pomfret and soak it in a mixture of ice and water at 4°C. After the fish enters a coma, continue soaking for 5 minutes.

[0066] S2. Clean the golden pomfret and bleed its tail for 4 minutes while hanging the fish.

[0067] S3. Wash the golden pomfret and drain the surface water.

[0068] S4. Soak the golden pomfret in a 200 mg / L chlorogenic acid solution for 10 minutes.

[0069] Example 5 Sample 8 (4 min bloodletting + immersion in 100 mg / L chlorogenic acid solution)

[0070] Same as Example 2, except that the tail bleeding time of S2 was 4 minutes.

[0071] Wash fresh golden pomfret and soak it in a mixture of ice and water at 4°C. After the fish enters a coma, continue soaking for 5 minutes.

[0072] S2. Clean the golden pomfret and bleed its tail for 4 minutes while hanging the fish.

[0073] S3. Wash the golden pomfret and drain the surface water.

[0074] S4. Soak the golden pomfret in a 100 mg / L chlorogenic acid solution for 10 minutes.

[0075] Comparative Example 1 Sample 9 (2 min bloodletting + 100 mg / L chlorogenic acid solution immersion)

[0076] Same as Example 2, except that the tail bleeding time of S2 was 2 minutes.

[0077] Wash fresh golden pomfret and soak it in a mixture of ice and water at 4°C. After the fish enters a coma, continue soaking for 5 minutes.

[0078] S2. Clean the golden pomfret and bleed its tail for 2 minutes while hanging the fish.

[0079] S3. Wash the golden pomfret and drain the surface water.

[0080] S4. Soak the golden pomfret in a 100 mg / L chlorogenic acid solution for 10 minutes.

[0081] Comparative Example 2 Sample 10 (2 min bloodletting + immersion in 200 mg / L chlorogenic acid solution)

[0082] Same as Example 3, except that the tail bleeding time of S2 was 2 minutes.

[0083] Wash fresh golden pomfret and soak it in a mixture of ice and water at 4°C. After the fish enters a coma, continue soaking for 5 minutes.

[0084] S2. Clean the golden pomfret and bleed its tail for 2 minutes while hanging the fish.

[0085] S3. Wash the golden pomfret and drain the surface water.

[0086] S4. Soak the golden pomfret in a 200 mg / L chlorogenic acid solution for 10 minutes.

[0087] Comparative Example 3 Sample 11 (2 min bloodletting)

[0088] The same as Comparative Example 1, except that S4 is not performed. The details are as follows:

[0089] Wash fresh golden pomfret and soak it in a mixture of ice and water at 4°C. After the fish enters a coma, continue soaking for 5 minutes.

[0090] S2. Clean the golden pomfret and bleed its tail for 2 minutes while hanging the fish.

[0091] S3. Wash the golden pomfret and drain the surface water.

[0092] Comparative Example 4 Sample 12 (4 min bloodletting)

[0093] Same as Example 5, except that S4 is not performed.

[0094] Wash fresh golden pomfret and soak it in a mixture of ice and water at 4°C. After the fish enters a coma, continue soaking for 5 minutes.

[0095] S2. Clean the golden pomfret and bleed its tail for 4 minutes while hanging the fish.

[0096] S3. Wash the golden pomfret and drain the surface water.

[0097] Comparative Example 5 Sample 13 (immersed in 100 mg / L chlorogenic acid solution)

[0098] Same as Example 2, except that S2 is not performed.

[0099] Wash fresh golden pomfret and soak it in a mixture of ice and water at 4°C. After the fish enters a coma, continue soaking for 5 minutes.

[0100] S2. Wash the golden pomfret and drain the surface water.

[0101] S3. Soak the golden pomfret in a 100 mg / L chlorogenic acid solution for 10 minutes.

[0102] Test Example 1

[0103] After wiping dry the surface moisture of the golden pomfret (Samples 5-13) treated in Examples 2-5 and Comparative Examples 1-5, the fish were placed in food-grade packaging bags. The air in the bags was evacuated using a vacuum packaging machine, and the bags were sealed. The fish were then frozen and stored in a -20°C freezer for 30 days. After 30 days of storage, the fish were removed and measured for centrifugal loss, cooking loss, hardness, springiness, and chewiness. Fresh golden pomfret (untreated, not stunned, bled, soaked, or frozen) served as a blank control, and golden pomfret (not stunned, bled, or soaked) that had been frozen and stored directly in a -30°C freezer for 30 days served as a positive control. The results are shown in Table 2.

[0104] Table 2

[0105] Centrifugal loss rate (%) Cooking loss rate (%) hardness elasticity chewability Example 2 (Sample 5) 9.02 15.34 1482.92 0.53 266.86 Example 3 (Sample 6) 9.19 15.35 1523.92 0.57 251.45 Example 4 (Sample 7) 9.90 15.77 1611.65 0.50 246.41 Example 5 (Sample 8) 10.33 16.02 1574.61 0.44 236.51 Comparative Example 1 (Sample 9) 10.68 16.64 1746.56 0.41 225.93 Comparative Example 2 (Sample 10) 10.48 16.59 1701.62 0.43 223.94 Comparative Example 3 (Sample 11) 10.96 17.00 1815.55 0.39 214.57 Comparative Example 4 (Sample 12) 10.41 16.53 1750.04 0.41 234.30 Comparative Example 5 (Sample 13) 11.13 17.22 1800.27 0.36 210.01 Blank control 10.56 16.71 1490.40 0.66 274.57 Positive control 9.11 15.40 1521.30 0.55 254.81

[0106] From Table 2 we can see that:

[0107] (1) The centrifugal loss rate and cooking loss rate of Examples 2 to 5 were lower than those of Comparative Examples 1 to 5 and the blank control group, and the centrifugal loss rate and cooking loss rate of Examples 2 to 3 were comparable to those of the positive control group, indicating that the method of the present invention can effectively improve the water retention of golden pomfret, and even achieve a level of water retention comparable to that of golden pomfret stored at -30°C while saving energy.

[0108] (2) The hardness, elasticity, chewiness and other textures of Examples 2 to 5 are closer to those of the blank control group than those of Comparative Examples 1 to 5, and the hardness, elasticity, chewiness and other textures of Examples 2 to 3 are comparable to those of the positive control group, indicating that the method of the present invention can enable the golden pomfret to maintain a high edible quality after long-term frozen storage, and can even achieve an edible quality level comparable to that of the golden pomfret stored at -30°C while saving energy.

[0109] (3) The centrifugal loss rate and cooking loss rate of Example 2 were lower than those of Comparative Example 1, and the hardness, elasticity, chewiness and other textures were closer to those of the blank control group than those of Comparative Example 1. The centrifugal loss rate and cooking loss rate of Example 3 were lower than those of Comparative Example 2, and the hardness, elasticity, chewiness and other textures were closer to those of the blank control group than those of Comparative Example 2. This indicates that in the method of the present invention, when the bleeding time is 4 to 10 minutes, the water retention of golden pomfret can be more effectively improved, and its edible quality can be maintained at a high level.

[0110] (4) The centrifugal loss rate and cooking loss rate of Comparative Example 1 were lower than those of Comparative Example 3, and the hardness, elasticity, chewiness and other textures were closer to those of the blank control group than those of Comparative Example 3; the centrifugal loss rate and cooking loss rate of Example 5 were lower than those of Comparative Example 4, and the hardness, elasticity, chewiness and other textures were closer to those of the blank control group than those of Comparative Example 4. This indicates that in the method of the present invention, the polyphenol solution soaking operation can more effectively improve the water retention of golden pomfret and maintain its high edible quality.

[0111] (5) The centrifugal loss rate and cooking loss rate of Example 2 were lower than those of Comparative Example 5, and the textures such as hardness, elasticity, and chewiness were closer to those of the blank control group than those of Comparative Example 5. This indicates that in the method of the present invention, bleeding can more effectively improve the water retention of golden pomfret and maintain its high edible quality.

[0112] Test Example 2

[0113] In order to explore the relationship between bloodletting and immersion in a polyphenol solution in the method of the present invention, this test example summarizes some of the data in Tables 1 and 2, and supplements sample 14 soaked in only 200 mg / L chlorogenic acid solution (the treatment method is the same as that of sample 13 in Comparative Example 5, except that the concentration of the S4 chlorogenic acid solution is 200 mg / L). The results are shown in Table 3.

[0114] Table 3

[0115] Cooking loss rate (%) Sample 1 (10 min bleeding) 16.15 Sample 13 (soaked in 100 mg / L chlorogenic acid solution) 17.22 Sample 14 (soaked in 200 mg / L chlorogenic acid solution) 16.50 Sample 5 (10 min bloodletting + immersion in 100 mg / L chlorogenic acid solution) 15.34 Sample 6 (10 min bloodletting + immersion in 200 mg / L chlorogenic acid solution) 15.35 Blank control (fresh golden pomfret) 16.71

[0116] From Table 3 we can see that:

[0117] (1) The cooking loss rate of sample 13 was higher than that of the blank control, indicating that soaking in 100 mg / L chlorogenic acid solution alone would reduce the water retention of golden pomfret. The cooking loss rate of sample 1 was 0.56% lower than that of the blank control, indicating that bleeding alone could only increase the cooking loss rate of golden pomfret by 0.56%. In contrast, sample 5, which was bled first and then soaked in 100 mg / L chlorogenic acid solution, reduced the cooking loss rate by 1.37% (>0.56%) compared with the blank control, indicating that the two process operations of bleeding and soaking in 100 mg / L chlorogenic acid solution in sample 5 played a synergistic role in improving the water retention of golden pomfret.

[0118] (2) The cooking loss rate of sample 1 was 0.56% lower than that of the blank control, indicating that bleeding alone could only increase the cooking loss rate of golden pomfret by 0.56%. The cooking loss rate of sample 14 was 0.21% lower than that of the blank control, indicating that soaking in 200 mg / L chlorogenic acid solution alone could only increase the cooking loss rate of golden pomfret by 0.21%. In contrast, the cooking loss rate of sample 6, which was treated by bleeding first and then soaking in 200 mg / L chlorogenic acid solution, was reduced by 1.36% (>0.56% + 0.21%), indicating that the bleeding and soaking in 200 mg / L chlorogenic acid solution in sample 6 played a synergistic role in improving the water retention of golden pomfret.

[0119] In summary, the present invention conducts a targeted exploration of the properties of golden pomfret, sequentially combines two main processes, namely a specific method of bleeding (coma bleeding) and a polyphenol solution soaking treatment, and specifically sets process parameters such as bleeding time, polyphenol solution concentration and soaking time. These links synergistically improve the water retention of golden pomfret, so that it can still maintain a high edible quality after long-term frozen storage and transportation in the later stage.

[0120] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be considered as equivalent replacement methods and are included in the scope of protection of the present invention.

Claims

1. A method for improving the water retention of golden pomfret, characterized in that: The steps include: S1. Bleed fresh golden pomfret for 4-10 minutes if the fish has been unconscious for more than 5 minutes. S2. Soak the golden pomfret obtained in S1 in a chlorogenic acid solution with a concentration of 100-200 mg / L for 8-12 minutes.

2. The method according to claim 1, characterized in that The coma described in S1 was achieved by soaking fresh golden pomfret in an ice-water mixture.

3. The method according to claim 2, wherein The temperature of the ice-water mixture is 0-4°C.

4. The method according to claim 1, characterized in that The bleeding described in S1 is tail bleeding or spinal bleeding.

5. The method according to claim 4, characterized in that: The bleeding is tail bleeding.

6. The method according to claim 1, wherein The bleeding time in S1 is 10 min.

7. The method according to claim 1, wherein The concentration of the chlorogenic acid solution in S2 is 100 mg / L.