Processing technology of instant tilapia skin

Abstract

The invention provides an instant tilapia skin processing technology. The instant tilapia skin processing technology comprises the steps of cleaning, descaling, shredding, deodorizing, blanching, crispness increasing, seasoning, sterilizing, packaging and the like. In the fishy smell removing step, fishy smell removing liquid is used for soaking and removing fishy smell, and the fishy smell removing liquid is composed of ginger juice, garlic juice, purple sweet potato extract and purified water. Wherein the fresh ginger juice and the garlic juice are mainly used for removing fishy smell through volatile components and a sterilizing effect, and the purple sweet potato extracting solution is mainly used for removing fishy smell through antioxidant and antibacterial effects and reaction with fishy smell substances. The three components complement and promote each other in the fishy smell removing process, and the comprehensive fishy smell removing effect is achieved. In the brittleness increasing step, the fish skin is soaked in a brittleness increasing solution to increase the brittleness, the brittleness increasing solution is composed of calcium lactate, sodium alginate, broad bean extract and purified water, and the components act synergistically through different mechanisms to jointly promote the fish skin to become brittle, so that the taste of the instant fish skin is improved.

Description

Technical Field

[0001] The invention relates to the technical field of food processing, and in particular to a processing technology for instant tilapia skin. Background Art

[0002] Tilapia has strong adaptability to the environment, strong reproductive capacity and fast growth rate, so it is widely cultivated in my country. my country's tilapia production has long been ranked first in the world. At present, the main processing method of tilapia is to process it into frozen whole fish and frozen tilapia fillets. A large amount of scraps are generated in the process of producing frozen tilapia fillets. Most processing companies process these scraps into feed for sale, which has low economic benefits. Tilapia skin accounts for a large proportion of tilapia scraps. Tilapia skin is rich in nutrients, rich in various amino acids and collagen, and has high nutritional value. At present, the processing of tilapia skin mainly focuses on the extraction of fish skin collagen, and there are fewer processes for processing into ready-to-eat products. Due to the heavy fishy smell of tilapia, it has become an obstacle to the promotion of ready-to-eat tilapia skin products. How to reduce or remove the fishy smell of tilapia skin has become a technical difficulty in breaking through ready-to-eat tilapia skin. Summary of the invention

[0003] In view of this, the present invention proposes a ready-to-eat tilapia skin processing technology to solve the above problems.

[0004] The technical solution of the present invention is achieved in this way: a processing technology for instant tilapia skin comprises the following steps:

[0005] S1. Cleaning: Place the scaled tilapia skin in water, wash away surface impurities and mucus, and drain.

[0006] S2. Descaling and shredding: The cleaned scaled tilapia skin is placed in a vacuum device under negative pressure for 5-10 minutes, taken out and placed in a descaling machine to remove the scales, and then shredded.

[0007] S3. Removing fishy smell: Soak the cut tilapia skin in a deodorizing liquid composed of ginger juice, garlic juice, purple sweet potato extract and purified water.

[0008] S4. Blanching: Place the deodorized tilapia skin into hot water for blanching.

[0009] S5. Crispness enhancement: soak the blanched tilapia skin in a crispness enhancement liquid, which is composed of calcium lactate, sodium alginate, broad bean extract and purified water.

[0010] S6. Seasoning: add minced garlic, minced ginger, white sugar, chili powder, pepper powder, salt and sesame oil to the tilapia skin after the crispening treatment for seasoning.

[0011] S7. Sterilization and packaging: The seasoned tilapia skin is placed in a plasma sterilization device for sterilization, and then vacuum packaged.

[0012] Furthermore, the negative pressure in S2 is -0.05 to -0.15 MPa, and the tilapia skin is cut into strips with a width of 0.3 to 0.5 cm.

[0013] Furthermore, during the S3 deodorization, the ratio of tilapia skin to deodorizing liquid is 1:(1-3), and the mixture is soaked for 40-50 minutes.

[0014] Furthermore, the volume ratio of ginger juice, garlic juice, purple sweet potato extract and pure water in the deodorizing liquid is (3-5):(1-3):(2-4):(20-30).

[0015] Furthermore, the purple sweet potato extract is obtained by the following method: fresh, insect-free and mildew-free purple sweet potatoes are washed, cut into 1-3 cm small pieces, placed in a grinder, crushed and passed through a 50-70 mesh screen to obtain purple sweet potato powder. Purified water is added according to a solid-liquid ratio of 1: (5-10), and citric acid of 2-4% by weight of the purple sweet potato is added at the same time. The mixture is stirred evenly and allowed to stand for 2-4 hours for leaching. After the leaching is completed, the extract is filtered and the filtrate is taken. The filtrate is then centrifuged at 6000-10000r / min for 10-20min, and the supernatant is taken. The supernatant is placed in a rotary evaporator and concentrated to 10-20% of the original solution volume at 50-60°C to obtain the purple sweet potato extract.

[0016] Furthermore, the temperature of the hot water in S4 is 87-95° C., and the blanching treatment time is 8-12 seconds.

[0017] Furthermore, during S5 brittleness enhancement, the ratio of tilapia skin to brittleness enhancement liquid is 1:(1-2), and the immersion is carried out for 25-35 minutes.

[0018] Furthermore, the mass volume ratio of calcium lactate, sodium alginate, broad bean extract and pure water in the crispening liquid of S5 is (2.0-3.0) g / mL:(0.5-1.0):(1.0-2.0):(10.0-20.0).

[0019] Further, the broad bean extract is obtained by the following method: fresh, insect-free, and mildew-free broad beans are washed, the shells are removed, and the broad bean powder is crushed in a grinder and passed through a 50-70 mesh screen to obtain broad bean powder. Pure water is added to the broad bean powder at a material-liquid ratio of 1: (4-8), and then a saturated calcium hydroxide solution is added to adjust the pH to 9.0. The mixed solution is placed in an ultrasonic processor and ultrasonically treated for 0.8-1.2 hours at 40-50° C., an ultrasonic power of 100-300W, and an ultrasonic frequency of 20-40kHz. The mixed solution after ultrasonic treatment is filtered and the filtrate is taken. The pH value of the filtrate is adjusted to 4.5-5.0 using hydrochloric acid with a concentration of 4M. The filtrate after pH adjustment is precipitated at 3-5° C. for 10-14 hours, and the precipitate is removed by filtration to obtain the filtrate. The filtrate is placed in a rotary evaporator and concentrated to dryness at 50-60° C. to obtain the broad bean extract.

[0020] Furthermore, the mass volume ratio g / mL of tilapia skin, minced garlic, minced ginger, white sugar, chili oil, salt, pepper oil, sesame oil, and vinegar in S6 is (90-100):(2.5-3.0):(0.5-1.5):(1.5-2.5):(2.0-4.0):(2.0-3.0):(1.5-3.0):(2.0-3.0):(2.5-3.5).

[0021] Furthermore, in S7, the plasma gas is selected from one of oxygen, nitrogen and argon, the discharge power is set to 40-60W, the gas flow rate is set to 60-100L / min, and the treatment is 5-10min.

[0022] Furthermore, the vacuum degree of the vacuum packaging in S7 is -0.08 to -0.12 MPa.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] (1) The present invention places the scaled tilapia skin into a vacuum device, and in a negative pressure environment, the air between the scales and the skin is extracted through negative pressure suction, thereby reducing the adhesion between the scales and the skin, and facilitating the subsequent shedding of the scales. The scales can then be easily removed by a descaling machine, thereby achieving a 100% descaling rate.

[0025] (2) The present invention removes the fishy smell by soaking in a deodorizing liquid composed of ginger juice, garlic juice, purple sweet potato extract, and pure water in a specific ratio, wherein ginger juice and garlic juice remove the fishy smell mainly through their volatile components and bactericidal effects, and purple sweet potato extract removes the fishy smell mainly through its antioxidant and antibacterial effects and reaction with fishy substances. These three components complement and promote each other in the deodorizing process, achieving a comprehensive deodorizing effect. In addition, ginger juice, garlic juice, and purple sweet potato extract can also add fragrance and umami to the fish skin, enhance its overall taste, and bring unique color and flavor to the fish skin.

[0026] (3) The present invention uses a crispening liquid composed of calcium lactate, sodium alginate, broad bean extract and purified water in a specific ratio to make the fish skin crisper. The several ingredients work synergistically through different mechanisms to promote the crisping of the fish skin, thereby improving the taste of the ready-to-eat fish skin. DETAILED DESCRIPTION

[0027] In order to better understand the technical content of the present invention, specific embodiments are provided below to further illustrate the present invention.

[0028] Unless otherwise specified, the experimental methods used in the embodiments of the present invention are all conventional methods.

[0029] Unless otherwise specified, the materials, reagents, etc. used in the embodiments of the present invention can be obtained from commercial sources.

[0030] Example 1

[0031] A processing technology for instant tilapia skin comprises the following steps:

[0032] S1. Cleaning: Place the scaled tilapia skin in water, wash away surface impurities and mucus, and drain.

[0033] S2. Descaling and shredding: The cleaned scaled tilapia skin is placed in a vacuum device under a negative pressure of -0.05 MPa for 10 minutes, taken out and placed in a descaling machine to remove the scales, and cut into strips with a width of 0.3 cm.

[0034] S3. Remove the fishy smell: The cut tilapia skin is placed in the fishy smell removal liquid with a material-liquid ratio of 1:1 and soaked for 40 minutes. The fishy smell removal liquid is composed of ginger juice, garlic juice, purple sweet potato extract and purified water with a volume ratio of 3:1:2:20. The purple sweet potato extract is obtained by the following method: fresh, insect-free and mildew-free purple sweet potatoes are washed, cut into 1 cm small pieces, placed in a grinder, crushed and passed through a 50-mesh sieve to obtain purple sweet potato powder. Pure water is added according to a material-liquid ratio of 1:5, and citric acid of 2% of the weight of the purple sweet potato is added at the same time. The mixture is stirred evenly and allowed to stand for 2 hours for leaching. After the leaching is completed, the extract is filtered and the filtrate is taken. The filtrate is then centrifuged at 6000r / min for 20 minutes, the supernatant is taken, and the supernatant is placed in a rotary evaporator and concentrated to 10% of the original solution volume at 50°C to obtain the purple sweet potato extract.

[0035] S4. Blanching: Place the deodorized tilapia skin into 87° C. hot water for blanching for 12 seconds.

[0036] S5. Brittleness enhancement: The blanched tilapia skin is placed in a brittleness enhancement liquid with a material-liquid ratio of 1:1 and soaked for 35 minutes. The brittleness enhancement liquid is composed of calcium lactate, sodium alginate, broad bean extract and purified water with a mass volume ratio of 2.0:0.5:1.0:10.0 g / mL. The broad bean extract is obtained by the following method: fresh, insect-free and mildew-free broad beans are washed, the shells are removed, and the broad beans are placed in a grinder and crushed and passed through a 50-mesh sieve to obtain broad bean powder. Pure water is added to the broad bean powder with a material-liquid ratio of 1:4, and then a saturated calcium hydroxide solution is added to adjust the pH to 9.0. The mixed solution is placed in an ultrasonic processor and ultrasonically treated for 1.2 hours at 40°C, an ultrasonic power of 100W, and an ultrasonic frequency of 20kHz. The mixed solution after ultrasonic treatment is filtered and the filtrate is taken. The pH value of the filtrate is adjusted to 4.5 using hydrochloric acid with a concentration of 4M. The filtrate after pH adjustment is precipitated at 3°C ​​for 10 hours, and the precipitate is removed by filtration to obtain the filtrate. The filtrate was placed in a rotary evaporator and concentrated to dryness at 50°C to obtain the broad bean extract.

[0037] S6. Seasoning: add minced garlic, minced ginger, white sugar, chili powder, pepper powder, salt and sesame oil to the brittle treated tilapia skin for seasoning. The mass volume ratio of tilapia skin, minced garlic, minced ginger, white sugar, chili oil, salt, pepper oil, sesame oil and vinegar is 90:2.5:0.5:1.5:2.0:2.0:1.5:2.0:2.5 in g / mL.

[0038] S7. Sterilization and packaging: Place the seasoned tilapia skin into a plasma sterilization device for sterilization, the plasma gas is selected from nitrogen, the discharge power is set to 40W, the gas flow is set to 60L / min, and the treatment is performed for 10 minutes. After sterilization, vacuum packaging is performed under a vacuum degree of -0.08MPa.

[0039] Example 2

[0040] A processing technology for instant tilapia skin comprises the following steps:

[0041] S1. Cleaning: Place the scaled tilapia skin in water, wash away surface impurities and mucus, and drain.

[0042] S2. Descaling and shredding: The cleaned scaled tilapia skin is placed in a vacuum device under a negative pressure of -0.10 MPa for 7.5 min, taken out and placed in a descaling machine to remove the scales, and cut into strips with a width of 0.4 cm.

[0043] S3. Remove the fishy smell: The cut tilapia skin is placed in the fishy smell removal liquid with a material-liquid ratio of 1:2 and soaked for 45 minutes. The fishy smell removal liquid is composed of ginger juice, garlic juice, purple sweet potato extract and purified water with a volume ratio of 4:2:3:25. The purple sweet potato extract is obtained by the following method: fresh, insect-free and mildew-free purple sweet potatoes are washed, cut into 2 cm small pieces, placed in a grinder, crushed and passed through a 60-mesh sieve to obtain purple sweet potato powder. Pure water is added according to a material-liquid ratio of 1:7.5, and 3% citric acid by weight of the purple sweet potato is added at the same time. The mixture is stirred evenly and allowed to stand for 3 hours for leaching. After the leaching is completed, the extract is filtered and the filtrate is taken. The filtrate is then centrifuged at 8000r / min for 15 minutes, the supernatant is taken, the supernatant is placed in a rotary evaporator, and concentrated to 15% of the original liquid volume at 55°C to obtain the purple sweet potato extract.

[0044] S4. Blanching: Place the deodorized tilapia skin into 90° C. hot water for blanching for 10 seconds.

[0045] S5. Brittleness enhancement: The blanched tilapia skin is placed in a brittleness enhancement liquid at a material-liquid ratio of 1:1.5 and soaked for 30 minutes. The brittleness enhancement liquid is composed of calcium lactate, sodium alginate, broad bean extract, and purified water at a mass volume ratio of 2.5:0.7:1.5:15.0 g / mL. The broad bean extract is obtained by the following method: fresh, insect-free, and mildew-free broad beans are washed, the shells are removed, and the broad beans are placed in a grinder and crushed and passed through a 60-mesh sieve to obtain broad bean powder. Pure water is added to the broad bean powder at a material-liquid ratio of 1:6, and then a saturated calcium hydroxide solution is added to adjust the pH to 9.0. The mixed solution is placed in an ultrasonic processor and ultrasonically treated for 1.0 h at 45°C, an ultrasonic power of 200W, and an ultrasonic frequency of 30kHz. The mixed solution after ultrasonic treatment is filtered and the filtrate is taken. The pH value of the filtrate is adjusted to 4.2 using hydrochloric acid at a concentration of 4M. The filtrate after pH adjustment is precipitated at 4°C for 12 hours, and the precipitate is removed by filtration to obtain the filtrate. The filtrate was placed in a rotary evaporator and concentrated to 20% of the original volume at 55° C. to obtain the broad bean extract.

[0046] S6. Seasoning: add minced garlic, minced ginger, white sugar, chili powder, pepper powder, salt and sesame oil to the brittle treated tilapia skin for seasoning. The mass volume ratio of tilapia skin, minced garlic, minced ginger, white sugar, chili oil, salt, pepper oil, sesame oil and vinegar is 95:2.8:1.0:2.0:3.0:2.5:2.4:2.5:3.0.

[0047] S7. Sterilization and packaging: Place the seasoned tilapia skin into a plasma sterilization device for sterilization, the plasma gas is selected from oxygen, the discharge power is set to 40-60W, the gas flow is set to 80L / min, and the treatment is 7.5min. After sterilization, vacuum packaging is performed under a vacuum degree of -0.10MPa.

[0048] Example 3

[0049] A processing technology for instant tilapia skin comprises the following steps:

[0050] S1. Cleaning: Place the scaled tilapia skin in water, wash away surface impurities and mucus, and drain.

[0051] S2. Descaling and shredding: The cleaned scaled tilapia skin is placed in a vacuum device under a negative pressure of -0.15 MPa for 5 minutes, taken out and placed in a descaling machine to remove the scales, and cut into strips with a width of 0.5 cm.

[0052] S3. Remove the fishy smell: The cut tilapia skin is placed in the fishy smell removal liquid with a material-liquid ratio of 1:3 and soaked for 50 minutes. The fishy smell removal liquid is composed of ginger juice, garlic juice, purple sweet potato extract and purified water with a volume ratio of 5:3:4:30. The purple sweet potato extract is obtained by the following method: fresh, insect-free and mildew-free purple sweet potatoes are washed, cut into 3 cm small pieces, placed in a grinder, crushed and passed through a 70-mesh sieve to obtain purple sweet potato powder. Pure water is added according to a material-liquid ratio of 1:10, and 4% citric acid by weight of the purple sweet potato is added at the same time. The mixture is stirred evenly and allowed to stand for 4 hours for leaching. After the leaching is completed, the extract is filtered and the filtrate is taken. The filtrate is then centrifuged at 10000r / min for 10 minutes, the supernatant is taken, the supernatant is placed in a rotary evaporator, and concentrated to dryness at 50-60°C to obtain the purple sweet potato extract.

[0053] S4. Blanching: Place the deodorized tilapia skin into 95° C. hot water for blanching for 8 seconds.

[0054] S5. Brittleness enhancement: The blanched tilapia skin is placed in a brittleness enhancement liquid with a material-liquid ratio of 1:2 and soaked for 25 minutes. The brittleness enhancement liquid is composed of calcium lactate, sodium alginate, broad bean extract and purified water with a mass volume ratio of 3.0:1.0:2.0:20.0 g / mL. The broad bean extract is obtained by the following method: fresh, insect-free and mildew-free broad beans are washed, the shells are removed, and the broad beans are placed in a grinder and crushed and passed through a 70-mesh sieve to obtain broad bean powder. Pure water is added to the broad bean powder with a material-liquid ratio of 1:8, and then a saturated calcium hydroxide solution is added to adjust the pH to 9.0. The mixed solution is placed in an ultrasonic processor and ultrasonically treated for 0.8h at 50°C, an ultrasonic power of 300W, and an ultrasonic frequency of 40kHz. The mixed solution after ultrasonic treatment is filtered and the filtrate is taken. The pH value of the filtrate is adjusted to 5.0 using hydrochloric acid with a concentration of 4M. The filtrate after pH adjustment is precipitated at 5°C for 14h, and the precipitate is removed by filtration to obtain the filtrate. The filtrate was placed in a rotary evaporator and concentrated to dryness at 60°C to obtain the broad bean extract.

[0055] S6. Seasoning: add minced garlic, minced ginger, white sugar, chili powder, pepper powder, salt and sesame oil to the brittle treated tilapia skin for seasoning. The mass volume ratio of tilapia skin, minced garlic, minced ginger, white sugar, chili oil, salt, pepper oil, sesame oil and vinegar is 100:3.0:1.5:2.5:4.0:-3.0:3.0:-3.0:3.5 in g / mL.

[0056] S7. Sterilization and packaging: Place the seasoned tilapia skin into a plasma sterilization device for sterilization, the plasma gas is selected from nitrogen, the discharge power is set to 60W, the gas flow is set to 100L / min, and the treatment is performed for 5 minutes. After sterilization, vacuum packaging is performed under a vacuum degree of -0.12MPa.

[0057] Comparative Example 1

[0058] Compared with Example 2, the difference between this comparative example and Example 2 is that the deodorizing liquid in S3 is composed of ginger juice, garlic juice and purified water in a volume ratio of 4:2:25.

[0059] Comparative Example 2

[0060] This comparative example is compared with Example 2, except that the embrittlement agent in S5 is replaced by an ice-water mixture of equal volume.

[0061] Comparative Example 3

[0062] The difference between this comparative example and Example 2 is that the crispening liquid consists of sodium alginate, broad bean extract and purified water in a mass volume ratio of g / mL of 0.7:1.5:15.0.

[0063] Comparative Example 4

[0064] The difference between this comparative example and Example 2 is that the embrittlement liquid consists of calcium lactate, sodium alginate and purified water in a mass volume ratio of 2.5:0.7:15.0 g / mL.

[0065] 1. Sensory evaluation of fishy smell and crispness

[0066] 10 trained personnel were selected as sensory evaluation panel members, and the instant tilapia skins prepared in Examples 1-3 and Comparative Examples 1-4 were evaluated for fishy smell and crispness by the sensory evaluation panel members. 100 g of the instant tilapia skins prepared in Examples 1-3 and Comparative Examples 1-4 were evaluated, and the average score of the evaluation panel was taken as the final score. The scores are shown in Table 2.

[0067] Table 1

[0068]

[0069] Table 2

[0070] Fishy Score Crispness score Example 1 9.4 9.6 Example 2 9.8 9.9 Example 3 9.6 9.5 Comparative Example 1 8.4 9.6 Comparative Example 2 9.5 9.0 Comparative Example 3 9.7 7.7 Comparative Example 4 9.4 8.0

[0071] It can be seen from Table 2 that the instant tilapia skins prepared in Examples 1-3 have no fishy smell and are very crisp. Among them, Example 2 has a better effect.

[0072] By comparing Example 2 with Comparative Example 1, the deodorizing liquid of Comparative Example 1 lacks the purple sweet potato extract, resulting in a significant impact on the deodorizing effect. This is because the cyanidin anthocyanidins, acylated anthocyanidins, and peony pigment anthocyanidins rich in the purple sweet potato extract have a strong antioxidant capacity, which can interrupt the oxidation chain reaction by scavenging free radicals, thereby inhibiting the occurrence of fat oxidation, thereby reducing the production of fishy substances in fish skin. Cyanidin anthocyanidins, peony pigment anthocyanidins, and acylated anthocyanidins can also inhibit the growth and reproduction of various microorganisms, and further reduce the production of fishy substances in fish skin by inhibiting the growth and reproduction of microorganisms. In addition, the structure of anthocyanidins contains multiple phenolic hydroxyl groups, which react with the fishy components in fish skin, thereby changing its chemical properties, thereby reducing the fishy smell. In Example 2, a deodorizing liquid composed of ginger juice, garlic juice, purple sweet potato extract, and purified water in a specific ratio is added, wherein ginger juice and garlic juice mainly remove the fishy smell through their volatile components and bactericidal effects, and purple sweet potato extract mainly removes the fishy smell through its antioxidant and antibacterial effects and reaction with fishy substances. These three ingredients complement and promote each other in the deodorizing process, achieving a comprehensive deodorizing effect.

[0073] By comparing Example 2 with Comparative Example 2, the brittle effect of Example 2 is better than that of Comparative Example 2. The calcium lactate in the brittle liquid of Example 2 contains calcium ions that react with the protein in the fish skin to form ionic bonds or covalent bonds, promote cross-linking between protein molecules, and thus make the protein structure inside the fish skin more compact, thereby improving the hardness and brittleness of the fish skin. The sodium alginate in the brittle liquid forms a stable gel structure with the protein in the fish skin, which helps to maintain the shape and integrity of the fish skin, and can also increase the elasticity and brittleness of the fish skin. Sodium alginate has good thickening and film-forming properties, and can improve the texture and appearance of fish skin products. In the brittle liquid, sodium alginate can form a protective film covering the surface of the fish skin to prevent the loss of moisture and nutrients, thereby increasing the brittleness of the fish skin. The L-3,4-dihydroxyphenylalanine contained in the broad bean extract in the brittle liquid may interact with specific enzymes or proteins in the fish skin tissue, causing changes in the muscle fiber structure, thereby making the fish skin brittle. The isourea and broad bean pyrimidine contained in the broad bean extract have certain redox catalytic activity. These redox active substances may act as catalysts to accelerate the chemical reaction between protein molecules in the fish skin tissue, such as forming covalent bonds or non-covalent bonds such as disulfide bonds and hydrogen bonds, thereby enhancing the interaction between protein molecules, making the fish skin tissue more compact and stable, thereby improving its crispness. In Example 2, calcium lactate, sodium alginate, and broad bean extract work synergistically through different mechanisms to jointly promote the crispness of fish skin. From the comparison of Example 2 in Table 2 with Comparative Examples 3-4, it can be seen that several ingredients are indispensable, and the lack of one of them greatly weakens the effect.

[0074] In order to verify the descaling effect of this processing technology, comparative example 5 is set to verify the descaling effect.

[0075] Comparative Example 5

[0076] The difference between this comparative example and Example 2 is that in S2, the tilapia skin is not subjected to negative pressure, that is, the tilapia skin after washing and draining is directly placed in the descaling machine to remove the scales.

[0077] 2. Descaling rate detection

[0078] Take 20 pieces of tilapia skin with scales of the same size and thickness, and randomly divide them into 4 groups, and perform descaling treatment on the tilapia skin with scales according to the descaling processes of Examples 1-3 and Comparative Example 5. After descaling, wash away the removed scales with clean water, map the surface area of ​​the unremoved scales, calculate the descaling rate according to the following formula, and record the results in Table 3:

[0079]

[0080] Table 3

[0081] Example 1 Example 2 Example 3 Comparative Example 5 Descaling rate / % 100％ 100％ 100％ 88％

[0082] As can be seen from Table 3, the fish scale removal effect can reach 100% using this processing technology. This is because, before removing the fish scales, the scaled tilapia skin is first placed in a vacuum device, and the air between the fish scales and the fish skin is extracted through the negative pressure suction effect under a negative pressure environment, thereby reducing the adhesion between the fish scales and the fish skin, making it easier to remove the fish scales later. The fish scales can then be easily removed by a descaling machine.

[0083] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A processing technology for instant tilapia skin, characterized in that: The following steps are involved: S1. Cleaning: Place the scaled tilapia skin in water, wash away surface impurities and mucus, and drain; S2. Descaling and shredding: The cleaned tilapia skin is placed in a vacuum device, under negative pressure for 5-10min, taken out and placed in a descaling machine to remove the scales, and cut into shreds; S3. To remove the fishy smell: The cut tilapia skin is placed in a deodorizing solution and soaked, the deodorizing solution is composed of ginger juice, garlic juice, purple potato extract, and purified water; S4. Blanching: The deodorized tilapia skin is placed in hot water for blanching; S5. Crisp: The blanched tilapia skin is immersed in a crisp solution, wherein the crisp solution is composed of calcium lactate, sodium alginate, broad bean extract and purified water; S6. Seasoning: Add minced garlic, minced ginger, sugar, chili powder, pepper powder, salt and sesame oil to the brittle tilapia skin for seasoning; S7. Sterilization and packaging: The seasoned tilapia skin is placed in a plasma sterilization device for sterilization, and then vacuum packaged.

2. A processing technology for instant tilapia skin as claimed in claim 1, characterized in that: The negative pressure in S2 is -0.05 to -0.15 MPa, and the tilapia skin is cut into strips with a width of 0.3 to 0.5 cm.

3. A processing technology for instant tilapia skin as claimed in claim 1, characterized in that: When removing the fishy smell in S3, the material-liquid ratio of tilapia skin to fishy smell removing liquid is 1:(1-3), and the mixture is soaked for 40-50 minutes.

4. A ready-to-eat tilapia skin processing process as claimed in claim 3, characterized in that: The volume ratio of ginger juice, garlic juice, purple sweet potato extract and pure water in the deodorizing liquid is (3-5):(1-3):(2-4):(20-30).

5. A ready-to-eat tilapia skin processing process as claimed in claim 1, characterized in that: The temperature of the hot water in S4 is 87-95° C., and the blanching treatment time is 8-12 seconds.

6. A ready-to-eat tilapia skin processing process as claimed in claim 1, characterized in that: During the S5 brittleness enhancement, the material-liquid ratio of the tilapia skin to the brittleness enhancement liquid is 1:(1-2), and the tilapia skin is soaked for 25-35 minutes.

7. A ready-to-eat tilapia skin processing process as claimed in claim 6, characterized in that: The mass volume ratio of calcium lactate, sodium alginate, broad bean extract and pure water in the crispening liquid of S5 is (2.0-3.0) g / mL: (0.5-1.0) g / mL: (1.0-2.0) g / mL: (10.0-20.0) g / mL.

8. A process for processing instant tilapia skin as claimed in claim 1, characterized in that: The mass volume ratios of tilapia skin, minced garlic, minced ginger, white sugar, chili oil, salt, pepper oil, sesame oil and vinegar in S6 are (90-100) g / mL: (2.5-3.0): (0.5-1.5): (1.5-2.5): (2.0-4.0): (2.0-3.0): (1.5-3.0): (2.0-3.0): (2.5-3.5).

9. A ready-to-eat tilapia skin processing process as claimed in claim 1, characterized in that: The plasma gas in S7 is selected from one of oxygen, nitrogen and argon, the discharge power is set to 40-60W, the gas flow rate is set to 60-100L / min, and the treatment is 5-10min.

10. The instant tilapia skin processing process according to claim 1, characterized in that: The vacuum degree of the vacuum packaging in S7 is -0.08 to -0.12 MPa.

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