A method for preparing a live fish bait

Abstract

The present application belongs to the field of fish bait preparation, and particularly relates to a preparation method of fresh fish bait. The present application takes animal bait, phosphate modified gluten, acidifier microcapsule and natural bacteriostatic agent as main raw materials, reduces water activity through phosphate modified gluten, acidifier microcapsule and natural bacteriostatic agent, inhibits microbial growth in multiple ways, cooperates with precise sterilization process, effectively slows down the spoilage speed of raw materials, abandons traditional sterilization process, optimizes 115 DEG C for 15 min, achieves the sterilization requirement at the same time, maximally retains the natural fishy smell of fresh fish bait, avoids large loss of fishy smell substances, and ensures the best fish luring effect. Moreover, the prepared fresh fish bait has low water activity, high fishy smell retention rate, high food luring rate, moderate dissolving rate, good stability, good storage resistance, food luring property and use adaptability, and can meet the long-term storage, transportation and circulation requirements.

Description

Technical Field

[0001] This invention belongs to the field of fish bait preparation technology, specifically relating to a method for preparing fresh fish bait. Background Technology

[0002] With the booming development of recreational fishing across the country, the market demand for high-quality, highly active fresh fish bait has surged. As one of the most important fish-attracting media in the fishing process, the quality of fresh fish bait directly affects the fishing results and user experience. Therefore, developing fresh fish bait products with excellent preservation properties and stable feeding effects has become an important direction for industry development.

[0003] Live bait typically includes earthworms, bloodworms, fish and shrimp, poultry offal, and other fresh animal-based ingredients. These ingredients are popular primarily because they retain their natural fishy and fragrant aroma, active forms, and abundant free amino acids, nucleotides, lipids, and other attracting components. They create a strong odor diffusion and stimulating effect in the water, significantly attracting most fish species. Compared to synthetic baits, live bait has clear advantages in biomimicry, fish-attracting efficiency, and adaptability to target fish species, thus maintaining a core position in actual fishing scenarios for a long time.

[0004] However, fresh fish bait, due to its high water content and rich nutrients, is extremely susceptible to spoilage during processing and storage. While existing preservation technologies can extend shelf life to some extent, they still have many shortcomings: 1) Traditional fresh fish bait has not undergone systematic antibacterial and sterilization treatment, and only relies on simple low-temperature storage, resulting in a very short shelf life, making it difficult to achieve industrialized production, long-distance transportation and long-term circulation. 2) Products using traditional meat sterilization processes (121℃, 30min) can meet sterilization requirements, but they will cause a large loss of fishy substances in fresh fish bait, greatly reducing the bait's attractiveness and failing to meet the core needs of fishing scenarios. 3) The lack of efficient compound antibacterial methods makes it impossible to effectively inhibit the growth of microorganisms during production and storage, which can easily lead to spoilage and affect product quality and safety.

[0005] Therefore, developing an efficient, safe, and economical fresh fish bait preservation process and establishing a processing system that balances antibacterial preservation and flavor retention is key to promoting the upgrading of the fishing industry and enhancing its market competitiveness. Summary of the Invention

[0006] In view of the above-mentioned defects in the existing technology, the purpose of this invention is to overcome the technical defects of existing fresh fish bait, such as easy perishability, serious loss of fishy smell after sterilization, and short shelf life. The invention provides a method for preparing fresh fish bait that, through precise thawing, compound antibacterial treatment, and optimized sterilization process, maximizes the preservation of the natural fishy smell and feeding effect of fresh fish bait while ensuring commercial sterility, extends the product shelf life, realizes industrialized production and long-term circulation, and meets the market demand for high-quality fresh fish bait.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A method for preparing fresh fish bait includes the following steps: S1. Thaw animal feed at 0-4℃ for 4-6 hours; S2. Put the thawed bait into a chopper and chop it at a speed of 3000-3500 rpm. During the chopping process, add phosphate-modified wheat gluten, acidifier microcapsules and natural antibacterial agent in sequence to obtain pretreated fresh fish bait. The temperature of the chopping process is controlled at 0-8℃. The mass ratio of the bait, phosphate-modified gluten powder, acidifying agent microcapsules, and natural antibacterial agent is (84~90):(10~16):(0.4~0.12):(0.02~0.2). The phosphate-modified wheat gluten powder includes compound phosphate, wheat gluten powder and glycerin; S3. Vacuum-seal the above-pretreated fresh bait, wherein the sealed packaging is a food-grade high-temperature resistant retort bag. S4. The pre-treated fresh fish bait, which is vacuum-sealed and packaged, is sterilized at 115℃ under high temperature and high pressure for 10~25 minutes, and then cooled to obtain fresh fish bait.

[0008] Preferably, the animal feed in step S1 is one or more of earthworms, bloodworms, sea fish, krill, and poultry offal in any proportion; the poultry offal is one or more of chicken, duck, and goose offal in any proportion.

[0009] As a preferred option, the specific operation method of step S2 is as follows: S201. After putting the bait into the chopper, chop it at 3000~3500rpm for 2~3 minutes, then add phosphate-modified wheat gluten powder and continue chopping for 3~5 minutes to obtain mixture A. S202. Add acidifying agent microcapsules to the above mixture B, stir for 2-3 minutes to adjust the pH to 4.5-5.5, and obtain mixture B; S203. Add a natural antibacterial agent to the above mixture B, and chop and mix for 1-2 minutes until completely uniform to obtain pretreated fresh fish bait.

[0010] Preferably, the preparation method of the phosphate-modified wheat gluten powder in step S201 is as follows: (1) Disperse gluten powder, glycerol and compound phosphate into distilled water to obtain mixture A with a water content of 15-30%; (2) Plasticize the above mixture A at 35~55℃ for 10~40 min to obtain phosphate modified gluten powder.

[0011] Preferably, the mass-volume ratio of the compound phosphate, gluten powder and glycerin in step (1) is (1~5):100:(8~18); in the mass-volume ratio, the solid is expressed in g and the liquid is expressed in ml.

[0012] Preferably, the composite phosphate is composed of sodium tripolyphosphate, sodium pyrophosphate and sodium hexametaphosphate in a mass ratio of (4~7):(1~4):(0.5~3).

[0013] Preferably, the preparation method of the acidifying agent microcapsules is as follows: (1) Lactic acid, citric acid and malic acid are compounded in a mass ratio of (1~3):(1~2):(0.5~1) to obtain a composite acidifier; (2) Disperse the composite wall material in distilled water and adjust the pH to 4.5~5.5 to obtain a composite wall material solution; the mass ratio of the composite wall material to distilled water is 1:(30~50); (3) The composite acidifier is added to the composite wall material solution, and after high-speed shear emulsification, calcium chloride solution is added for ionic cross-linking. Then, after freeze drying, acidifier microcapsules are obtained.

[0014] Preferably, the composite acidifier mentioned in step (1) is the core material, and the composite wall material mentioned in step (2) is a compound of gluten hydrolysate, chitosan and sodium alginate in a mass ratio of (2~5):(1~3):1; the mass ratio of the core material to the composite wall material is 1:(1.5~4).

[0015] Preferably, the preparation method of the gluten hydrolysate is as follows: dispersing gluten in distilled water, adjusting the pH to 6.5~9.0, then adding protease for enzymatic hydrolysis, and after the reaction, performing enzyme inactivation treatment at 85~95℃ for 5~15min, followed by filtration and freeze drying to obtain gluten hydrolysate; the mass ratio of gluten, protease and distilled water is (5~15):(0.5~5):(80~90).

[0016] Preferably, the natural antibacterial agent is a compound of chitosan and tea polyphenols in a mass ratio of (1~3):1.

[0017] Compared with the prior art, the present invention has the following beneficial effects: (1) Through the compound antibacterial method of reducing water activity by phosphate-modified gluten powder, acidifying agent microcapsules and natural antibacterial agents, the growth of microorganisms is inhibited in many ways. Combined with the precise sterilization process, the spoilage rate of raw materials is effectively slowed down. After being tested at a constant temperature of 37℃ for 7 days, it reaches commercial sterility and has a shelf life of up to 18 months, realizing long-term storage and circulation of products.

[0018] (2) An optimized sterilization process of 115℃ for 15 minutes is adopted, abandoning the traditional meat sterilization process of 121℃ for 30 minutes. While meeting the sterilization requirements, the natural fishy smell of fresh fish bait is preserved to the maximum extent, avoiding the loss of a large amount of fishy substances and ensuring the best fish-attracting effect.

[0019] (3) The steps are simple and industrial production can be achieved without complicated equipment; all raw materials used are food-grade and safe with no residue; at the same time, it can be adapted to various fresh fish bait raw materials such as earthworms, bloodworms, fish and shrimp, and poultry offal, with strong compatibility and can meet the feeding needs of different fishing scenarios and different fish species, making it highly practical. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0021] To achieve the above-mentioned objectives of the present invention, the technical solution of the present invention will be further described in detail below, but the scope of protection of the present invention is not limited to the following description.

[0022] A method for preparing fresh fish bait includes the following steps: S1. Take animal feed and thaw it at a low temperature of 0~4℃ for 4~6 hours; avoid excessively high temperature causing premature spoilage of raw materials, or excessively low temperature causing incomplete thawing and uneven chopping. Low-temperature thawing, with a thawing time of 4-6 hours, ensures uniform thawing of raw materials, while minimizing the loss of nutrients and natural flavor, thus preparing them for subsequent processing. S2. Place the thawed bait into a chopper and chop it at a speed of 3000-3500 rpm to ensure uniform crushing. During chopping, add phosphate-modified wheat gluten, acidifier microcapsules, and natural antibacterial agent sequentially. The mass ratio of the bait, phosphate-modified wheat gluten, acidifier microcapsules, and natural antibacterial agent is (84-90):(10-16):(0.04-0.12):(0.02-0.2). The specific operating method is as follows: S201. After putting the bait into a chopper, chop it at 3000~3500 rpm for 2~3 minutes, then add phosphate-modified wheat gluten powder and continue chopping for 3~5 minutes to obtain mixture A; the preparation method of the phosphate-modified wheat gluten powder is as follows: (1) Disperse gluten powder, glycerin and compound phosphate into distilled water to obtain mixture A with a water content of 15~30%; the compound phosphate is composed of sodium tripolyphosphate, sodium pyrophosphate and sodium hexametaphosphate in a mass ratio of (4~7):(1~4):(0.5~3); (2) Plasticize the above mixture A at 35~55℃ for 10~40 min to obtain phosphate modified gluten powder.

[0023] S202. Add the acidifying agent microcapsules to the above mixture B, stir for 2-3 minutes, and adjust the pH to 4.5-5.5 to obtain mixture B; the acidifying agent microcapsules are composed of core material and composite wall material in a mass ratio of 1:(1.5-4); the specific preparation method is as follows: (1) Lactic acid, citric acid and malic acid are compounded in a mass ratio of (1~3):(1~2):(0.5~1) to obtain a composite acidifier, and the composite acidifier is used as the core material; (2) Mix the composite wall material with distilled water at a mass ratio of 1:(30~50) and adjust the pH to 4.5~5.5 to obtain a composite wall material solution; the composite wall material is composed of hydrolysate of gluten, chitosan and sodium alginate at a mass ratio of (2~5):(1~3):1. The preparation method of the gluten hydrolysate is as follows: gluten powder is dispersed in distilled water, the pH is adjusted to 6.5~9.0, then protease is added for enzymatic hydrolysis, after the reaction is completed, enzyme inactivation treatment is carried out at 85~95℃ for 5~15min, and then filtered and freeze-dried to obtain gluten hydrolysate; the mass ratio of gluten powder, protease and distilled water is (5~15):(0.5~5):(80~90).

[0024] (3) Mix the core material and composite wall material solution evenly, and shear at high speed of 6000~12000rpm for 2~8min. Then add 0.5~2.0wt% calcium chloride solution for ionic cross-linking, and then freeze dry to obtain acidifier microcapsules; The regulation system mainly utilizes the characteristic that the growth of microorganisms is inhibited in a weakly acidic environment, thereby slowing down the spoilage rate of fresh fish bait during the production process and thus extending the shelf life of fresh fish bait.

[0025] S203. Add a natural antibacterial agent to the above mixture B, and chop and mix for 1-2 minutes until completely uniform to obtain pretreated fresh fish bait; the natural antibacterial agent is a mixture of chitosan and tea polyphenols in a mass ratio of (1-3):1. Acidifying agent microcapsules are used to adjust the system pH to 4.2-4.5 to inhibit the growth and reproduction of putrefactive and pathogenic bacteria and reduce endogenous enzyme activity. Wheat gluten has good water absorption and retention properties, which can bind some of the water in the system and form a network structure, reducing the free water content. Glycerin, as a humectant and water activity reducing component, can reduce water activity by binding with water molecules, thereby limiting microbial metabolic activity. Complex phosphates can further delay oxidation and putrefaction processes by chelating metal ions, improving protein water retention, and enhancing system stability. The synergistic effect of these components can effectively reduce the system's water activity, inhibit microbial growth, and slow down protein degradation, thereby delaying the rate of raw material putrefaction. S3. The pre-treated fresh bait is sealed and packaged; the sealed packaging is vacuum sealed to prevent secondary contamination after sterilization and to extend the shelf life of the product. S4. The pre-treated fresh fish bait, which is vacuum-sealed and packaged, is sterilized at 115℃ under high temperature and high pressure for 10~25 minutes, and then cooled to obtain fresh fish bait.

[0026] Testing and verification: After cooling, the fresh fish bait was placed in a constant temperature incubator at 36℃ for 7-14 days and samples were taken for observation and testing; the product was sealed and stored in a normal temperature (25±2℃) environment and tracked for 12-18 months to observe the condition of the product.

[0027] Example 1 A method for preparing fresh fish bait includes the following steps: S1. Take fresh earthworms as raw material and thaw them in a low temperature environment of 0~4℃ for 5 hours until the earthworms are completely thawed, there are no ice crystals left, and there is no putrid odor. S2. The thawed earthworms are fed into a chopper at a speed of 3200 rpm to ensure even chopping. During the chopping process, phosphate-modified wheat gluten, acidifier microcapsules, and a natural antibacterial agent are added sequentially to obtain a uniform pre-treated fresh fish bait. The mass ratio of the bait, phosphate-modified wheat gluten, acidifier microcapsules, and natural antibacterial agent is 87:13:0.1:0.15. The specific operating method is as follows: S201. After adding the bait to the chopper, chop at 3200 rpm for 2.5 minutes, then add phosphate-modified wheat gluten and continue chopping for 4 minutes to obtain mixture A; the preparation method of the phosphate-modified wheat gluten is as follows: (1) Disperse gluten powder, glycerin and compound phosphate into distilled water to obtain mixture A with a water content of 22%; the compound phosphate is composed of sodium tripolyphosphate, sodium pyrophosphate and sodium hexametaphosphate in a mass ratio of 6:2.5:1.5; (2) The above mixture A was plasticized at 45°C for 25 min to obtain phosphate modified gluten powder.

[0028] S202. Add acidifying agent microcapsules to the above mixture B, stir for 2.5 min, adjust the pH to 4.8, and obtain mixture B; the acidifying agent microcapsules are prepared by compounding core material and composite wall material in a mass ratio of 1:3, and the specific preparation method is as follows: (1) Lactic acid, citric acid and malic acid are compounded in a mass ratio of 2:2:1 to obtain a composite acidifier, and the composite acidifier is used as the core material; (2) Mix the composite wall material with distilled water at a mass ratio of 1:40 and adjust the pH to 4.8 to obtain a composite wall material solution; the composite wall material is a compound of wheat gluten hydrolysate, chitosan and sodium alginate at a mass ratio of 4:2:1. The preparation method of the gluten powder hydrolysate is as follows: gluten powder is dispersed in distilled water, the pH is adjusted to 8, then protease is added for enzymatic hydrolysis, after the reaction is completed, enzyme inactivation is performed at 90℃ for 10 min, and then filtered and freeze-dried to obtain gluten powder hydrolysate; the mass ratio of gluten powder, protease and distilled water is 10:3:87.

[0029] (3) Mix the core material and composite wall material solution evenly, shear at 8000 rpm for 5 min, then add 1.5 wt% calcium chloride solution for ionic cross-linking, and then freeze dry to obtain acidifier microcapsules; S203. Add a natural antibacterial agent to the above mixture B, and chop and mix for 1.5 minutes until completely uniform to obtain pretreated fresh fish bait; the natural antibacterial agent is a compound of chitosan and tea polyphenols in a mass ratio of 2:1. S3. The pre-treated fresh bait is sealed and packaged; the sealed packaging is vacuum sealed to prevent secondary contamination after sterilization and to extend the shelf life of the product. S4. The pre-treated fresh fish bait, which is vacuum-sealed and packaged, is sterilized at 115°C and high pressure for 20 minutes. After cooling, the fresh fish bait is obtained.

[0030] Testing and Validation: The product meets commercial sterility standards; after being sealed and stored at room temperature (25±2℃) for 18 months, the product showed no signs of spoilage or odor, retained the natural fishy smell of earthworms, and showed no significant decrease in its fish-attracting effect.

[0031] Example 2 A method for preparing fresh fish bait includes the following steps: S1. Take a mixture of marine fish, bloodworms and krill in a mass ratio of 5:3:2 and place it in a low temperature environment of 0~4℃ to thaw for 4 hours; until the raw materials are completely thawed and there are no signs of spoilage, wash and remove impurities. S2. Place the thawed bait into a chopper and chop it at 3500 rpm to ensure uniform crushing. During chopping, add phosphate-modified wheat gluten, acidifier microcapsules, and a natural antibacterial agent sequentially. The mass ratio of the bait, phosphate-modified wheat gluten, acidifier microcapsules, and natural antibacterial agent is 84:16:0.12:0.13. The specific operating method is as follows: S201. After adding the bait to the chopper, chop at 3500 rpm for 2 minutes, then add phosphate-modified wheat gluten and continue chopping for 3 minutes to obtain mixture A; the preparation method of the phosphate-modified wheat gluten is as follows: (1) Disperse gluten powder, glycerin and compound phosphate into distilled water to obtain mixture A with a water content of 30%; the compound phosphate is composed of sodium tripolyphosphate, sodium pyrophosphate and sodium hexametaphosphate in a mass ratio of 7:2:1; (2) The above mixture A was plasticized at 55°C for 10 min to obtain phosphate modified gluten powder.

[0032] S202. Add acidifying agent microcapsules to the above mixture B, stir for 3 minutes, adjust the pH to 4.5, and obtain mixture B; the acidifying agent microcapsules are composed of core material and composite wall material in a mass ratio of 1:4; the specific preparation method is as follows: (1) Lactic acid, citric acid and malic acid are compounded in a mass ratio of 3:1:1 to obtain a composite acidifier, and the composite acidifier is used as the core material; (2) Mix the composite wall material with distilled water at a mass ratio of 1:50 and adjust the pH to 4.5 to obtain a composite wall material solution; the composite wall material is composed of hydrolysate of gluten, chitosan and sodium alginate at a mass ratio of 5:1:1. The preparation method of the gluten hydrolysate is as follows: gluten powder is dispersed in distilled water, the pH is adjusted to 8.5, then protease is added for enzymatic hydrolysis, after the reaction is completed, enzyme inactivation is performed at 95℃ for 5 minutes, and then filtered and freeze-dried to obtain gluten hydrolysate; the mass ratio of gluten powder, protease and distilled water is 15:5:80.

[0033] (3) Mix the core material and composite wall material solution evenly, shear at 12000rpm for 3min, then add 2wt% calcium chloride solution for ionic cross-linking, and then freeze dry to obtain acidifier microcapsules.

[0034] S203. Add a natural antibacterial agent to the above mixture B, and chop and mix for 2 minutes until completely uniform to obtain pretreated fresh fish bait; the natural antibacterial agent is a mixture of chitosan and tea polyphenols in a mass ratio of 1:1. S3. The pre-treated fresh bait is sealed and packaged; the sealed packaging is vacuum sealed to prevent secondary contamination after sterilization and to extend the shelf life of the product. S4. The pre-treated fresh fish bait, which is vacuum-sealed and packaged, is sterilized at 115°C and high pressure for 15 minutes, and then cooled to obtain fresh fish bait.

[0035] Testing and Validation: The product meets commercial sterility standards; after being sealed and stored at room temperature (25±2℃) for 18 months, the product shows no signs of spoilage or off-odor, retains the natural fishy smell of the raw materials, and its fish-attracting effect does not significantly decrease.

[0036] Example 3 A method for preparing fresh fish bait includes the following steps: S1. Take fresh chicken offal and place it in a low temperature environment of 0~4℃ to thaw for 6 hours until it is completely thawed; S2. Place the thawed bait into a chopper and chop it at 3000 rpm to ensure uniform crushing. During chopping, add phosphate-modified wheat gluten, acidifier microcapsules, and a natural antibacterial agent sequentially. The mass ratio of the bait, phosphate-modified wheat gluten, acidifier microcapsules, and natural antibacterial agent is 90:10:0.08:0.17. The specific operating method is as follows: S201. After adding the bait to the chopper, chop at 3000 rpm for 3 minutes, then add phosphate-modified wheat gluten and continue chopping for 5 minutes to obtain mixture A; the preparation method of the phosphate-modified wheat gluten is as follows: (1) Disperse gluten powder, glycerin and compound phosphate into distilled water to obtain mixture A with a water content of 15%; the compound phosphate is composed of sodium tripolyphosphate, sodium pyrophosphate and sodium hexametaphosphate in a mass ratio of 5:3:2; (2) The above mixture A was plasticized at 35°C for 40 min to obtain phosphate-modified gluten powder.

[0037] S202. Add the acidifying agent microcapsules to the above mixture B, stir for 2 minutes, adjust the pH to 5.2, and obtain mixture B; the acidifying agent microcapsules are composed of core material and composite wall material in a mass ratio of 1:2; the specific preparation method is as follows: (1) Lactic acid, citric acid and malic acid are compounded in a mass ratio of 2.5:2:0.5 to obtain a composite acidifier, and the composite acidifier is used as the core material; (2) Mix the composite wall material with distilled water at a mass ratio of 1:30 and adjust the pH to 5.2 to obtain a composite wall material solution; the composite wall material is composed of hydrolysate of gluten, chitosan and sodium alginate in a mass ratio of 3:3:1. The preparation method of the gluten powder hydrolysate is as follows: gluten powder is dispersed in distilled water, the pH is adjusted to 9, then protease is added to carry out enzymatic hydrolysis, after the reaction is completed, enzyme inactivation treatment is carried out at 85℃ for 15 min, and then filtered and freeze-dried to obtain gluten powder hydrolysate; the mass ratio of gluten powder, protease and distilled water is 12:4:84.

[0038] (3) Mix the core material and composite wall material solution evenly, shear at 6000 rpm for 8 min, then add 0.5 wt% calcium chloride solution for ionic cross-linking, and then freeze dry to obtain acidifier microcapsules; S203. Add a natural antibacterial agent to the above mixture B, chop and mix for 1 minute until completely uniform, to obtain pretreated fresh fish bait; the natural antibacterial agent is a mixture of chitosan and tea polyphenols in a mass ratio of 3:1. S3. The pre-treated fresh bait is sealed and packaged; the sealed packaging is vacuum sealed to prevent secondary contamination after sterilization and to extend the shelf life of the product. S4. The pre-treated fresh fish bait, which is vacuum-sealed and packaged, is sterilized at 115°C and high pressure for 25 minutes. After cooling, the fresh fish bait is obtained. Testing and Validation: The product meets commercial sterility standards; after being sealed and stored at room temperature (25±2℃) for 18 months, the product shows no signs of spoilage or off-odor, retains the natural fishy smell of the raw materials, and its fish-attracting effect does not significantly decrease.

[0039] Comparative Example 1 Compared with Example 2, the traditional sterilization process of 121℃ for 30 minutes was used; the rest of the operations and parameters were completely consistent with Example 2.

[0040] Comparative Example 2 Compared with Example 1, the gluten powder was not modified with phosphate, and the other operations and parameters were completely the same as in Example 1.

[0041] Comparative Example 3 Compared with Example 1, the phosphate-modified gluten powder was removed, and the other operations and parameters were completely the same as in Example 1.

[0042] Comparative Example 4 Compared with Example 1, the acidifier microcapsules were removed, but the rest of the operations and parameters were completely the same as in Example 1.

[0043] Comparative Example 5 Compared with Example 1, the natural antibacterial agent was removed, but the rest of the operation and parameters were completely the same as in Example 1.

[0044] The fresh fish bait prepared using this invention was subjected to physicochemical and performance tests. The physicochemical tests mainly focused on water activity, while the performance tests mainly focused on fishy smell retention rate, feeding attraction rate, and dissolution rate.

[0045] (1) Physicochemical testing: Water activity is an important indicator for evaluating the risk of microbial growth in fresh fish bait.

[0046] As shown in Table 1, in Examples 1-3, the water activity was low due to the presence of phosphate-modified wheat gluten, acidifying agent microcapsules, and natural antibacterial agents. However, in Comparative Examples 2-4, the proportion of free water in the system increased after the absence of any of the above components, resulting in a significant increase in water activity. This indicates that phosphate-modified wheat gluten, acidifying agent microcapsules, and natural antibacterial agents have a positive effect on reducing free water and enhancing system stability.

[0047] (2) Performance testing: The fishy smell retention rate is used to evaluate the degree to which the original natural fishy and fresh flavor of the fish bait is retained after sterilization, reflecting whether the basic attractant is destroyed; the attractant rate is used to measure the attraction and feeding promotion effect of the fish bait on the target fish, reflecting its actual use value; the dissolution rate is used to evaluate the structure retention and release performance of the fish bait after entering the water, reflecting its water resistance, formability and the continuous release ability of effective attractant components.

[0048] As shown in Table 1, the fishy smell retention rate of Examples 1-3 was 86.5-88.2%, which was more than 60% higher than that of Comparative Example 1. Furthermore, the palatability rate of Examples 1-3 was 28.6-30.5%, which was more than 45% higher than that of Comparative Example 1. The two sets of data indicate that the sterilization conditions of 115℃ for 15min can reduce the loss of palatability flavor caused by excessive heat treatment. Comparative Example 1 used traditional high-temperature long-term sterilization at 121℃ for 30min, which was more intense in heat treatment. This may be due to the loss of volatile fishy smell substances, oxidation or heat denaturation of proteins and fats, which led to a decrease in the original fresh palatability flavor and thus a decrease in the palatability rate.

[0049] Meanwhile, the 30-minute dissolution rate of Examples 1-3 was controlled between 15.4% and 18.6%, and the stability met the requirements. This indicates that the formula can improve the fish bait's shape retention and storage stability after entering the water while maintaining the natural fishy smell and feeding activity of the animal bait. In contrast, Comparative Example 1 suffered from a decrease in fishy smell retention and feeding dominance due to excessively high sterilization intensity; Comparative Examples 2-4 suffered from increased water activity, increased dissolution rate, and decreased stability due to the lack of phosphate-modified gluten powder, acidifying agent microcapsules, or natural antibacterial agents.

[0050] Therefore, acidifiers, gluten, glycerin, and compound phosphates have a good synergistic effect with the 115℃ high-temperature and high-pressure sterilization conditions, which can effectively balance the freshness, palatability, and stability of fresh fish bait.

[0051] The fresh fish bait prepared by this invention achieved commercial sterility after 7 days of constant temperature incubation at 37℃, indicating excellent microbial control and high food and storage safety. Furthermore, its shelf life reaches 18 months, demonstrating good quality stability during long-term storage and distribution. Moreover, the fresh fish bait prepared by this invention not only effectively inhibits microbial growth and spoilage but also retains the natural palatability of the raw materials, enhancing its attraction to fish. It also maintains structural integrity and continuous release capacity after entering the water, thus balancing freshness, palatability, stability, and commercial application value.

[0052] Finally, it should be noted that although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the present invention.

Claims

1. A method for preparing fresh fish bait, characterized in that, Includes the following steps: S1. Thaw animal feed at 0-4℃ for 4-6 hours; S2. Put the thawed bait into a chopper and chop it at a speed of 3000-3500 rpm. During the chopping process, add phosphate-modified wheat gluten, acidifying agent microcapsules and natural antibacterial agent in sequence to obtain pretreated fresh fish bait. The chopping temperature is controlled at 0-8℃. The mass ratio of the bait, phosphate-modified gluten powder, acidifying agent microcapsules, and natural antibacterial agent is (84~90):(10~16):(0.4~0.12):(0.02~0.2). The phosphate-modified wheat gluten powder includes compound phosphate, wheat gluten powder and glycerin; S3. Vacuum-seal the above-pretreated fresh bait, wherein the sealed packaging is a food-grade high-temperature resistant retort bag. S4. The pre-treated fresh fish bait, which is vacuum-sealed and packaged, is sterilized at 115℃ under high temperature and high pressure for 10~25 minutes, and then cooled to obtain fresh fish bait.

2. The method for using fresh fish bait according to claim 1, characterized in that, The animal feed mentioned in step S1 is one or more of earthworms, bloodworms, sea fish, krill, and poultry offal in any proportion; the poultry offal is one or more of chicken, duck, and goose offal in any proportion.

3. The method for using fresh fish bait according to claim 1, characterized in that, The specific operation method for step S2 is as follows: S201. After putting the bait into the chopper, chop it at 3000~3500rpm for 2~3 minutes, then add phosphate-modified wheat gluten powder and continue chopping for 3~5 minutes to obtain mixture A. S202. Add acidifying agent microcapsules to the above mixture B, stir for 2-3 minutes to adjust the pH to 4.5-5.5, and obtain mixture B; S203. Add a natural antibacterial agent to the above mixture B, and chop and mix for 1-2 minutes until completely uniform to obtain pretreated fresh fish bait.

4. The method for using fresh fish bait according to claim 3, characterized in that, The preparation method of the phosphate-modified gluten powder in step S201 is as follows: (1) Disperse gluten powder, glycerol and compound phosphate into distilled water to obtain mixture A with a water content of 15-30%; (2) Plasticize the above mixture A at 35~55℃ for 10~40 min to obtain phosphate modified gluten powder.

5. The method for using fresh fish bait according to claim 4, characterized in that, The mass-volume ratio of the compound phosphate, gluten powder and glycerin in step (1) is (1~5):100:(8~18); the solids in the mass-volume ratio are expressed in g and the liquids in ml.

6. The method for using fresh fish bait according to claim 4 or 5, characterized in that, The composite phosphate is composed of sodium tripolyphosphate, sodium pyrophosphate and sodium hexametaphosphate in a mass ratio of (4~7):(1~4):(0.5~3).

7. The method for using fresh fish bait according to claim 3, characterized in that, The preparation method of the acidifier microcapsules is as follows: (1) Lactic acid, citric acid and malic acid are compounded in a mass ratio of (1~3):(1~2):(0.5~1) to obtain a composite acidifier; (2) Disperse the composite wall material in distilled water and adjust the pH to 4.5~5.5 to obtain a composite wall material solution; the mass ratio of the composite wall material to distilled water is 1:(30~50); (3) The composite acidifier is added to the composite wall material solution, and after high-speed shear emulsification, calcium chloride solution is added for ionic cross-linking. Then, after freeze drying, acidifier microcapsules are obtained.

8. The method for using fresh fish bait according to claim 7, characterized in that, The composite acidifier mentioned in step (1) is the core material, and the composite wall material mentioned in step (2) is a compound of gluten hydrolysate, chitosan and sodium alginate in a mass ratio of (2~5):(1~3):1; the mass ratio of the core material and the composite wall material is 1:(1.5~4).

9. The method for using fresh fish bait according to claim 8, characterized in that, The preparation method of the gluten hydrolysate is as follows: gluten powder is dispersed in distilled water, the pH is adjusted to 6.5~9.0, then protease is added for enzymatic hydrolysis, after the reaction is completed, enzyme inactivation treatment is carried out at 85~95℃ for 5~15min, and then filtered and freeze-dried to obtain gluten hydrolysate; the mass ratio of gluten powder, protease and distilled water is (5~15):(0.5~5):(80~90).

10. The method for using fresh fish bait according to claim 3, characterized in that, The natural antibacterial agent is a compound of chitosan and tea polyphenols in a mass ratio of (1~3):1.

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