Preparation method of high-temperature-resistant synthetic roe for pets

Abstract

The invention relates to the field of pet food, and particularly discloses a preparation method of high-temperature-resistant synthetic roe for pets. The preparation method of the high-temperature-resistant synthetic roe for pets comprises the following steps: uniformly mixing a curdlan solution and a sodium alginate solution to prepare a wall material solution; uniformly mixing the calcium liquid, the acid liquid, the emulsifier, the suspending agent and the nutrient substances to prepare a mixed glue solution, mixing the mixed glue solution with edible oil, and shearing to prepare a core material glue solution; dropwise adding the core material glue solution into the wall material solution to react for 5-10 minutes, separating, washing, sterilizing and packaging to obtain the synthetic roe. The synthetic roe provided by the invention can be used in wet cat food, hair paste, cat strips and other pet food, and has the advantages of high-temperature sterilization resistance, elasticity maintenance, no rupture, high antioxidant energy and high mechanical strength.

Description

Technical Field

[0001] This application relates to the field of pet food technology, and more specifically, it relates to a method for preparing heat-resistant synthetic caviar for pets. Background Technology

[0002] With the increasing popularity of refined pet feeding concepts, nutritional supplementation for pets such as dogs and cats is receiving more and more attention. Key nutrients such as fish oil, krill oil, and taurine have become important functional additives in pet food due to their health-promoting effects on pets' skin, coat, cardiovascular system, vision, and nervous system. Currently, there are two main technical approaches to supplementing these nutrients: one is the direct addition method, which involves directly mixing fish oil, taurine, etc., into the wet food base of cat food, canned food, cat treats, or hairball remedy. While this method is simple, it has significant limitations: firstly, some nutrients (such as unsaturated fatty acids) are easily oxidized and deteriorate, resulting in poor stability; secondly, some ingredients themselves have fishy or unpleasant odors that pets dislike, affecting the overall palatability of the product; and thirdly, it cannot achieve targeted or controlled-release delivery of nutrients. The other approach is the encapsulation and post-addition method, which involves encapsulating nutrients using technologies such as microencapsulation before incorporating them into the food. This method effectively isolates nutrients from oxygen and light, improving nutrient stability, masking unpleasant flavors, and allowing for slow-release or targeted release through design. In recent years, a type of "pet sphere" that mimics the shape of caviar has become a market hotspot. It encapsulates nutrients in tiny gel spheres, has a novel appearance, and enhances the pet's feeding experience.

[0003] Existing pet food microspheres are mostly solid gel spheres, whose microstructure differs fundamentally from the cystic structure of natural caviar (i.e., having internal liquid cavities or core-shell structures). Patent application number [application number missing] discloses a method for preparing microcapsules loaded with lutein using gellan gum and sodium alginate as wall materials. The resulting product is solid gel microparticles with a uniform particle size distribution, leading to a low loading of active substances per unit volume. Furthermore, to ensure commercial sterility and extend shelf life, wet pet food typically undergoes rigorous high-temperature sterilization (e.g., 121°C, maintained for 1-2 hours). This necessitates that added functional particles, including synthetic caviar, possess excellent heat resistance, maintaining structural integrity, without cracking, melting, or leakage, and without significant degradation or inactivation of core nutrients during this process.

[0004] In response to the aforementioned technologies, the current pet nutrition supplement field urgently needs to develop a new type of high-temperature resistant synthetic caviar that can mimic the cystic structure of natural caviar to achieve a better loading rate of active substances, while also meeting the high-temperature sterilization process of wet pet food. Summary of the Invention

[0005] In order to achieve the uniform size and sealed cavity structure of real fish roe, while meeting the requirements of 121℃ sterilization in pet food and increasing the nutrient loading, this application provides a method for preparing high-temperature resistant synthetic fish roe for pets.

[0006] In a first aspect, this application provides a method for preparing high-temperature resistant synthetic fish roe for pets, employing the following technical solution: A method for preparing heat-resistant synthetic caviar for pets includes the following steps: The wall material solution is prepared by mixing the guar gum solution and the sodium alginate solution evenly. Calcium solution, acid solution, emulsifier, suspending agent and nutrients are mixed evenly to prepare mixed adhesive solution. Mix the mixed adhesive solution with edible oil and cut to prepare core material adhesive solution. The core material adhesive solution is dropped into the wall material solution and reacted for 5-10 minutes. After separation, washing, sterilization, and packaging, synthetic caviar is obtained.

[0007] By adopting the above technical solution, a mixture of gellan gum and sodium alginate is used as the wall material, which can provide the framework of thermally irreversible gel and the initial network of ionic cross-linking for synthetic caviar. The core material contains calcium source, acid, emulsifier, edible oil and nutrients. When the core material solution is added to the wall material solution, the calcium ions in the core material diffuse outward and come into contact with the sodium alginate in the wall material, instantly forming a dense calcium alginate gel film on the surface of the droplet, which constitutes the initial, flexible capsule wall. The acid inside the core material reacts with carbonate (calcium carbonate as the calcium source) to produce carbon dioxide gas. These gases are captured by the emulsifier and gel network, forming microbubbles or pores inside the droplet, thereby supporting the internal cavity. The suspending agent helps stabilize the gas-liquid-oil multiphase system and prevents the active ingredients from settling. After separation, sterilization heat treatment is performed to heat-set the gellan gum, thereby locking the entire capsule structure and making it less prone to collapse during subsequent sterilization at 121°C.

[0008] Compared to the technical solution disclosed in CN120549891A, which involves mixing sodium alginate, guar gum, calcium source, and acid in a single step to form a solid gel block, this application utilizes a step-by-step, zoned reaction to first form an interfacial film, and then generate gas inside to create a cavity. This achieves a cavity-building process from the outside in, allowing the cavity structure to accommodate more liquid core material and increase the nutrient loading rate. The loading rate is no longer limited by the physical adsorption or embedding of molecules by the gel network. Furthermore, the main body of the wall material is still guar gum, which has high thermal irreversibility and is not prone to losing its skeletal structure at high temperatures. The calcium alginate membrane also has thermal stability. In addition, the internal cavity releases some thermal expansion stress, making the entire structure less prone to rupture due to excessive internal pressure during high-temperature sterilization, further enhancing its stability.

[0009] Preferably, the wall material solution also contains nanocellulose and polyvinyl alcohol, and the mass ratio of sodium alginate, nanocellulose and polyvinyl alcohol is 2:1-1.4:1.1-1.5.

[0010] By adopting the above technical solutions, nanocellulose possesses extremely high aspect ratio and strength, enabling it to form a nano-network structure within the gellan gum / sodium alginate gel network. This improves the tensile strength, modulus, and puncture resistance of the wall material, making the synthetic caviar more robust and less prone to flattening or breakage during processing or transportation. Furthermore, the crystalline regions of nanocellulose can form dense physical cross-linking points and exhibit excellent oxygen barrier properties, extending the diffusion path of oxygen within the wall material, enhancing antioxidant capacity, and protecting the antioxidant effect of the core material. In addition, nanocellulose itself has good heat resistance, and its nano-network can restrict the thermal movement of polymer chains at high temperatures, making the gel network less prone to relaxation or collapse at 121°C. Therefore, nanocellulose not only improves the mechanical properties and barrier properties of synthetic caviar but also provides a thermally stable framework for the entire wall material gel, increasing the heat distortion temperature and allowing the synthetic caviar to maintain its shape during high-temperature sterilization.

[0011] Polyvinyl alcohol (PVA) can form strong and flexible polymer films, and it has good compatibility with gellan gum and sodium alginate. It can fill the microcracks in brittle gel networks through hydrogen bonding, absorb impact energy, and make the wall material both strong and tough, preventing brittle fracture. PVA can promote the formation of more continuous and defect-free films. In synergy with nanocellulose, it can further reduce the micro-defects of the wall material and improve the overall barrier properties. Therefore, the addition of nanocellulose and PVA to the wall material can improve the mechanical strength, toughness, oxygen barrier properties (i.e., antioxidant capacity), and heat resistance and shape stability of the synthetic caviar.

[0012] Preferably, the polyvinyl alcohol is PEG2000 or PEG4000.

[0013] By adopting the above technical solution, the polyvinyl alcohol has a high degree of polymerization and high heat resistance, and can form a thermally irreversible network, thereby improving its heat resistance.

[0014] Preferably, the following pretreatment is performed after washing and before sterilization: Carboxymethylated guar gum and chitosan were dissolved separately to prepare carboxymethylated guar gum solution and chitosan solution; A blend was prepared by mixing carboxymethylated guar gum solution and chitosan solution. Add the washed product to the blending solution, circulate and soak 2-3 times, then remove the washed product.

[0015] By adopting the above technical solution, the polyvinyl alcohol molecular chains added to the wall material solution are rich in hydroxyl groups. When soaking in the blend solution, the carboxymethyl guarana in the solution carries a negative charge, and the chitosan carries a positive charge. The blend solution penetrates into the surface layer of the wall material, and the hydroxyl groups of polyvinyl alcohol form a dense hydrogen bond network with the carboxyl / hydroxyl groups of carboxymethyl guarana and the amino / hydroxyl groups of chitosan. Moreover, the long-chain polyvinyl alcohol physically entangles with the penetrated chitosan and carboxymethyl guarana, forming an interpenetrating network. Therefore, through hydrogen bond network and physical entanglement, the inner and outer polymer layers can be bonded together. Nanocellulose also contains a large number of hydroxyl groups, which can also serve as active sites for hydrogen bonds, forming a hydrogen bond network with chitosan and carboxymethyl guarana. Furthermore, nanocellulose forms nanoscale protrusions and complex structures on the wall material, which can increase the physical bonding between the wall material and chitosan and carboxymethyl guarana. With its interface area and mechanical interlocking ability, the outer network structure undergoes elastic deformation, pore wall bending, and even collapse under external force, thereby absorbing and dissipating mechanical energy. During mixing, pumping, and filling, it can buffer mechanical stress and prevent synthetic caviar from being crushed on the processing line. Moreover, when pets chew, they first experience the softness and toughness of the outer porous gel, requiring greater biting force to penetrate and reach the internal cavity, achieving a texture that is tough at first and then crisp, bursting with flavor instantly. It is not easy to break accidentally under non-chewing conditions and provides a pleasant sense of release when eating. Furthermore, the network structure provides more thermal expansion / contraction buffers, reducing the concentration of thermal stress caused by the temperature difference between the inside and outside, making the overall structure more stable. At the same time, chitosan has antioxidant and antibacterial activities, forming an external active protective layer that can delay oxygen penetration, creating a dual protective effect of chemical protection and physical barrier.

[0016] Preferably, the concentration of the carboxymethylated gelatin is 3-5 wt%; and the concentration of the chitosan solution is 3-5 wt%.

[0017] By adopting the above technical solution, the concentrations of the two substances are adjusted, and they form an electrolyte complex through electrostatic interaction, which is enhanced by hydrogen bonding, resulting in a complete and firmly bonded external protective layer.

[0018] Preferably, the volume ratio of the carboxymethylated guar gum solution to the chitosan solution is 1:1-3.

[0019] By adopting the above technical solutions, the volume ratio ensures that the outer protective layer has a strong thermally stable framework, and chitosan is sufficient to provide antibacterial properties and positively charged binding. During the freeze-thaw process, carboxymethylated guar gum can more easily form a continuous gel network that supports a porous structure.

[0020] Preferably, the ratio of the calcium solution, acid solution, and suspending agent is 1-1.5:1-1.5:0.8-1.2; The amount of emulsifier used is 1‰-3‰ of the mass of the core material adhesive; The ratio of the mixed adhesive solution to edible oil is 2-3:7-8.

[0021] Preferably, the concentration of the calcium solution is 3-10 wt%, and the calcium source is at least one of calcium chloride, calcium lactate, and calcium carbonate; The concentration of the suspending agent is 0.3-0.8 wt%, and the suspending agent is selected from at least one of xanthan gum aqueous solution, locust bean gum aqueous solution, and prickly pear gum aqueous solution; The acid concentration is 3-10 wt%, and it is selected from at least one of hydrochloric acid, acetic acid, and gluconolactone.

[0022] Preferably, the edible oil is selected from at least one of corn oil, soybean oil, and olive oil; The nutrient is at least one of lutein, fish oil, krill oil, and astaxanthin.

[0023] Preferably, the nutrient is at least one of lutein, fish oil, krill oil, and astaxanthin.

[0024] Preferably, the preparation method of the gellan gum solution is as follows: dispersing gellan gum in water, then adjusting the pH of the system to 10-12, and stirring evenly to obtain the gellan gum solution; the preparation method of the sodium alginate solution is as follows: dissolving sodium alginate in water by stirring, then allowing it to stand to remove air bubbles, and obtaining the sodium alginate solution.

[0025] Preferably, the sterilization temperature is 80-95℃ and the sterilization time is 20-40 minutes.

[0026] In summary, this application has the following beneficial effects: 1. Due to the rapid reaction characteristics of sodium alginate and calcium, the synthetic caviar is quickly formed into a uniform sealed cavity structure. The property of gellan gum to gel when dissolved in acid at a pH of 10-12 is utilized to gel with sodium alginate, making the gel structure of the wall material uniform. The property of gellan gum to form an irreversible thermal gel when heated to above 85°C is utilized to form synthetic caviar that can withstand a high temperature of 121°C.

[0027] 2. The synthetic caviar produced in this application has an internal nutrient concentration of over 50%, which is much higher than that of solid gel caviar. In addition, sodium alginate in the wall material is a natural polysaccharide extracted from brown algae. The gel has the characteristics of being gastric insoluble and enteric-soluble. Together with kerogen gum, it protects the nutrients in the core material to reach the pet's intestines and releases them precisely. Sodium alginate dissolved in the intestines also has the effects of lubrication and hair-retaining, promoting the excretion of hair from the pet's intestines through feces and protecting the pet's intestinal health.

[0028] 3. The method of this application preferably uses a blend of carboxymethylated guar gum and chitosan to soak the separated product and perform two freeze-thaw cycles to form a network gel skeleton on the surface of the synthetic caviar, thereby improving the elastic deformation of the synthetic caviar, making it break during mixing, pumping and filling, while increasing the chewability of pets, improving the thermal shock resistance, and making the overall structure more stable. Detailed Implementation

[0029] The present application will be further described in detail below with reference to the embodiments.

[0030] Example 1 of the preparation of carboxymethylated gellan gum: 80 mL of isopropanol and 3 g of gellan gum were mixed and stirred at room temperature for 30 min. Then, 7 mL of 30% sodium hydroxide solution was added in 7 portions with an interval of 7 min each time. The mixture was stirred at room temperature for 90 min. The temperature was raised to 55 °C, and a mixed solution of 3.6 g of chloroacetic acid and 7 mL of isopropanol was added dropwise in 7 portions with an interval of 7 min each time. After the addition was completed, the mixture was stirred for 4 h to obtain a crude product. The crude product was washed alternately with anhydrous ethanol and acetone, dissolved in deionized water at room temperature, dialyzed at room temperature for 4 days, concentrated by rotary evaporation, and freeze-dried to obtain carboxymethylated gellan gum. Example

[0031] In the following examples, polyvinyl alcohol PEG-400 was selected from Yunsheng Chemical, model number 8792; PEG-2000 was selected from Jiangsu Haian Petrochemical; nanocellulose was selected from Zhejiang Jinjiahao Green Nanotechnology, model number CNF-85; and chitosan was selected from Xi'an Xihai Biotechnology, catalog number XH544.

[0032] Example 1: A method for preparing heat-resistant synthetic caviar for pets, comprising the following steps: S1. Disperse guar gum in deionized water, adjust the pH to 11.5 with 0.1M sodium hydroxide solution, and stir until homogeneous to obtain a 2wt% guar gum solution; stir sodium alginate in deionized water, and after complete dissolution, let it stand for 30 minutes to remove air bubbles to obtain a 2wt% sodium alginate solution. S2. Mix 2000ml of the gellan gum solution and 2000ml of the sodium alginate solution obtained in step S1 evenly to obtain the wall material solution; S3. Mix 120ml of 3wt% calcium solution (calcium lactate), 120ml of 3wt% acid solution (gluconolactone), 100ml of 0.6wt% suspending agent (xanthan gum aqueous solution), 32g of nutrient (lutein), and 1.1g of emulsifier (Span 80) and stir evenly to obtain a mixed glue solution. Add 746g of edible oil (olive oil) to the mixed glue solution, mix, and then emulsify at high speed to obtain the core material glue solution. S4. Using a syringe, the core material adhesive is dripped into the wall material solution. After reacting for 7 minutes, the solution is separated, washed, and sterilized at a temperature of 85°C for 30 minutes. The solution is then packaged to obtain synthetic caviar.

[0033] Add 10g of sterilized synthetic caviar to wet food cans or cat treats and sterilize at 121℃ for 1 hour before selling.

[0034] Example 2: A method for preparing heat-resistant synthetic caviar for pets, comprising the following steps: S1. Disperse the gellan gum evenly in deionized water, adjust the pH to 12 using a 0.1M sodium hydroxide solution to obtain a 3wt% gellan gum solution, add sodium alginate to deionized water, stir until completely dissolved, let stand for 30 minutes to remove air bubbles, and obtain a 3wt% sodium alginate solution. S2. Mix 2000ml of the gellan gum solution and 2000ml of the sodium alginate solution obtained in step S1 evenly to prepare the wall material solution. S3. Mix 240ml of 4% calcium solution (calcium lactate), 240ml of 3wt% acid solution (gluconolactone), 200ml of 0.6wt% suspending agent (xanthan gum aqueous solution), 64g of nutrient (lutein), and 2.1g of emulsifier (polyglycerol-2-dimeric hydroxystearate), stir evenly to obtain a mixed adhesive solution, add 1736g of edible oil (corn oil) to the mixed adhesive solution, mix, and emulsify by high-speed shearing to obtain the core material adhesive solution; S4. Using a syringe, the core material adhesive is dripped into the wall material solution. After reacting for 9 minutes, the solution is separated, washed, and sterilized at a temperature of 90°C for 40 minutes. The solution is then packaged to obtain synthetic caviar.

[0035] Example 3: A method for preparing high-temperature resistant synthetic fish roe for pets, which differs from Example 1 in that, in step S2, 2000 ml of the gellan gum solution and 2000 ml of sodium alginate solution obtained in step S1 are mixed evenly, nanocellulose and polyvinyl alcohol are added, and mixed evenly to obtain a wall material solution. The mass ratio of nanocellulose, polyvinyl alcohol and sodium alginate is 1.4:1.5:2, and the polyvinyl alcohol is PEG-4000.

[0036] Example 4: A method for preparing high-temperature resistant synthetic fish roe for pets, which differs from Example 1 in that, in step S2, 2000 ml of the gellan gum solution and 2000 ml of sodium alginate solution obtained in step S1 are mixed evenly, nanocellulose and polyvinyl alcohol are added, and mixed evenly to obtain a wall material solution. The mass ratio of nanocellulose, polyvinyl alcohol and sodium alginate is 1:1.1:2, and the polyvinyl alcohol is PEG-2000.

[0037] Example 5: A method for preparing high-temperature resistant synthetic fish roe for pets, which differs from Example 3 in that, in step S2, 2000 ml of the gellan gum solution and 2000 ml of sodium alginate solution obtained in step S1 are mixed evenly, nanocellulose is added and mixed evenly to obtain a wall material solution, wherein the mass ratio of nanocellulose to sodium alginate is 1.4:2, and polyvinyl alcohol is PEG-4000.

[0038] Example 6: A method for preparing high-temperature resistant synthetic fish roe for pets, which differs from Example 3 in that, in step S2, 2000 ml of the gellan gum solution and 2000 ml of sodium alginate solution obtained in step S1 are mixed evenly, polyvinyl alcohol is added, and mixed evenly to obtain a wall material solution. The mass ratio of polyvinyl alcohol to sodium alginate is 1.9:2, and the polyvinyl alcohol is PEG-4000.

[0039] Example 7: A method for preparing high-temperature resistant synthetic caviar for pets, which differs from Example 3 in that, in step S4, the core material adhesive is dripped into the wall material solution using a syringe, and after reacting for 7 minutes, the mixture is separated to obtain the separated product, which is then rinsed to obtain the washed product. Carboxymethylated guar gum was dissolved in deionized water to prepare a 5 wt% carboxymethylated guar gum solution. Chitosan was dissolved in sterile water containing 1% (w / w) glacial acetic acid and stirred until dissolved to prepare a 5 wt% chitosan solution. The carboxymethylated guar gum was prepared from Preparation Example 1. A blend was prepared by mixing carboxymethylated guar gum solution and chitosan solution at a volume ratio of 1:1. The washed material was added to the blending solution, circulated and soaked 3 times, and then sterilized at a temperature of 85°C for 30 minutes. After packaging, synthetic caviar was obtained.

[0040] Example 8: A method for preparing high-temperature resistant synthetic caviar for pets, which differs from Example 3 in that, in step S4, the core material adhesive is dripped into the wall material solution using a syringe, and after reacting for 7 minutes, the mixture is separated to obtain the separated product, which is then washed to obtain the washed product. Carboxymethylated guar gum was dissolved in deionized water to prepare a 3 wt% carboxymethylated guar gum solution. Chitosan was dissolved in sterile water containing 1% (w / w) glacial acetic acid and stirred until dissolved to prepare a 3 wt% chitosan solution. The carboxymethylated guar gum was prepared from Preparation Example 1. A blend was prepared by mixing carboxymethylated guar gum solution and chitosan solution at a volume ratio of 1:3. The washed material was added to the blending solution, circulated and soaked 3 times, and then sterilized at a temperature of 85°C for 30 minutes. After packaging, synthetic caviar was obtained.

[0041] Example 9: A method for preparing high-temperature resistant synthetic caviar for pets, which differs from Example 7 in that, in step S4, the core material adhesive is dripped into the wall material solution using a syringe, and after reacting for 7 minutes, the mixture is separated to obtain the separated product, which is then washed to obtain the washed product. Dissolve guar gum in deionized water to obtain a guar gum solution with a concentration of 3wt%. Dissolve chitosan in sterile water containing 1% (w / w) glacial acetic acid and stir until dissolved to obtain a chitosan solution with a concentration of 3wt%. The gellan gum solution and chitosan solution were mixed evenly at a volume ratio of 1:3 to obtain a blend. The washed material was added to the blending solution, circulated and soaked 3 times, sterilized at 85℃ for 30 minutes, and then packaged to obtain synthetic caviar.

[0042] Example 10: A method for preparing high-temperature resistant synthetic caviar for pets, which differs from Example 1 in that, in step S4, the core material adhesive is dripped into the wall material solution using a syringe, and after reacting for 7 minutes, the mixture is separated to obtain the separated product, which is then washed to obtain the washed product. Carboxymethylated guar gum was dissolved in deionized water to prepare a 3 wt% carboxymethylated guar gum solution. Chitosan was dissolved in sterile water containing 1% (w / w) glacial acetic acid and stirred until dissolved to prepare a 3 wt% chitosan solution. The carboxymethylated guar gum was prepared from Preparation Example 1. A blend was prepared by mixing carboxymethylated guar gum solution and chitosan solution at a volume ratio of 1:3. The washed material was added to the blending solution, circulated and soaked 3 times, and then sterilized at a temperature of 85°C for 30 minutes. After packaging, synthetic caviar was obtained.

[0043] Comparative Example

[0044] Comparative Example 1: Following the method disclosed in Example 1 of CN120549891A, a lutein-loaded guar gum-sodium alginate microcapsule was prepared. (1) Guar gum was dispersed in deionized water, and the pH of the system was adjusted to 11.5 using sodium hydroxide solution (concentration 0.1M) to obtain a 2% guar gum solution for later use. Sodium alginate was stirred in deionized water, and after complete dissolution, it was allowed to stand for 30 minutes to remove bubbles to obtain a 2% sodium alginate solution for later use. (2) The guar gum solution and sodium alginate solution obtained in step (1) were mixed at a volume ratio of 2:1 to obtain a mixed solution. 40 mL of the mixed solution was mixed with 0.8 g of calcium carbonate powder (CaCO3) for 30 minutes, and then 40 mg of lutein powder was added and stirred to achieve uniform dispersion to obtain a mixture. (3) The mixture obtained in step (2) was mixed with 80 mL of soybean oil containing 0.8 mL of Span 80 and stirred at 300 rpm for 15 min to form a water-in-oil emulsion. Then, 20 mL of soybean oil containing 800 μL of glacial acetic acid was added to the water-in-oil emulsion while stirring, and the mixture was stirred at 300 rpm for 15 min to promote coagulation. The mixture was then washed with deionized water and centrifuged (the washing and centrifugation steps were performed three times each to remove the oil phase and excess water). The final solid precipitate was the lutein-loaded guaran gum-sodium alginate microcapsules.

[0045] Performance testing

[0046] Products were prepared according to the methods in the examples and comparative examples, and various performance tests were performed according to the following methods. The test results are recorded in Table 1.

[0047] 1. Heat resistance: Take 50g of the product to be tested into a high-temperature resistance test bottle, add an appropriate amount of pH neutral buffer solution (simulating the moisture environment of wet grain), sterilize in an autoclave at 121℃ for 1h, and after natural cooling to room temperature, take the sterilized sample, spread it evenly in a petri dish, and observe the total number of particles N before and after sterilization using a stereomicroscope. Calculate the breakage rate according to the following formula: (N before sterilization - N after sterilization) / N before sterilization × 100%; Take 2g of synthetic caviar before and after sterilization, add 10mL of anhydrous ethanol-n-hexane mixture (volume ratio 1:1), ultrasonically extract for 30min (power 300W, temperature 25℃), centrifuge at 5000r / min for 10min, and take the supernatant; repeat the extraction twice, combine the supernatants and make up to 25mL, and detect by HPLC. Chromatographic conditions: C18 column (250mm×4.6mm, 5μm); mobile phase: methanol- Water (95:5 by volume); flow rate 1.0 mL / min; detection wavelength 445 nm; column temperature 30 ℃; injection volume 20 μL. The lutein retention rate was calculated as C1 / C0×100%, where C1 is the chlorophyll concentration after sterilization and C0 is the chlorophyll concentration before sterilization.

[0048] 2. Lutein oxidative degradation rate: 20g of synthetic caviar was placed in a constant temperature and humidity chamber, with the temperature set at 60℃ and the relative humidity at 75% for 14 days. The chlorophyll content was determined by HPLC and the chlorophyll concentration was calculated according to the following formula: ln(C / C0)=-kt, where C is the lutein concentration at 14 days and k is the degradation rate constant. The smaller the value of k, the stronger the antioxidant capacity.

[0049] 3. Resistance to compression and cracking: Synthetic caviar was selected and tested using a texture analyzer with a P / 5 probe (5mm cylindrical probe). The speed before testing was 2mm / s, the testing speed was 1mm / s, and the speed after testing was 2mm / s. The trigger force was 5g, and the compression distance was 50% of the caviar particle size. Ten synthetic caviar particles were tested in each group, and the average value was calculated.

[0050] 4. Encapsulation Efficiency: Lutein was dissolved in anhydrous ethanol to obtain solutions with different concentration gradients. The anhydrous ethanol solution served as a blank control, and the absorbance was measured at 446 nm using a UV spectrophotometer. Finally, a lutein standard curve was plotted with lutein concentration on the x-axis and absorbance on the y-axis. 100 mg of synthetic caviar was accurately weighed, added to anhydrous ethanol, and sonicated to dissolve the particles. The solution was then diluted to a final volume of 10 mL with anhydrous ethanol. The solution was centrifuged at 4000 rpm for 5 min at 4°C, and the supernatant was appropriately diluted. The absorbance was measured at 446 nm to calculate the total lutein content. Alternatively, 100 mg of synthetic caviar was accurately weighed, added to anhydrous ethanol to a final volume of 10 mL, vortexed for 30 s, and then centrifuged at 4000 rpm for 5 min at 4°C. After appropriate dilution, the absorbance of the supernatant was measured at a wavelength of 446 nm to calculate the surface lutein content. The formula for calculating the embedding rate is: embedding rate (%) = (1 - surface lutein content / total lutein content) × 100.

[0051] Table 1

[0052] Based on the raw material usage in Examples 1-2 and the data in Table 1, it can be seen that in Examples 1 and 2, the rapid properties of sodium alginate and calcium are utilized to give the synthetic caviar a sealed cavity structure, increasing the encapsulation rate. Moreover, the wall material structure is uniform, heat-resistant, and has a low breakage rate even after sterilization at 121°C for 1 hour, demonstrating good structural stability at high temperatures.

[0053] Compared with Example 1, Examples 3 and 4 added nanocellulose and polyvinyl alcohol to the wall material solution. The data in Table 1 show that the lutein encapsulation rate in the synthetic caviar produced by this method did not change significantly, but the breakage rate after sterilization at 121°C for 1 hour decreased, and the lutein retention rate increased at high temperature, the heat oxidation resistance increased, the oxidative degradation rate decreased, the breaking force increased, and the mechanical properties enhanced.

[0054] Compared with Example 3, Example 5 added nanocellulose to the wall material solution, while Example 6 used polyvinyl alcohol instead of nanocellulose. The data in Table 1 show that the synthetic caviar produced had reduced resistance to high-temperature cracking and oxidation.

[0055] Compared with Example 3, Examples 7 and 8 involved immersing the washed product in a blend of carboxymethyl guarana and chitosan for three cycles. As a result, the synthetic caviar prepared in Examples 7 and 8 showed significantly increased breaking force, reduced breakage rate after high-temperature sterilization, enhanced heat resistance, and decreased oxidative degradation rate.

[0056] Compared with Example 7, in Example 9, the synthetic fish roe was soaked in a blend of chitosan and guar gum in a cyclic soaking solution. It can be seen that the breaking force of the synthetic fish roe was reduced, while the oxidative degradation rate and high temperature stability did not change much. This indicates that soaking the synthetic fish roe in a blend of carboxymethylated guar gum and chitosan can significantly increase the mechanical strength of the synthetic fish roe.

[0057] Compared with Example 1, Example 10 involved cyclically soaking the washed product in a blend of chitosan and carboxymethylated guar gum. Compared with Example 1, the breaking force increased, the breakage rate decreased, and the antioxidant capacity increased. However, compared with Examples 3 and 7, the performance was still inferior. This indicates that by first adding nanocellulose and polyvinyl alcohol to the wall material and then cyclically soaking the washed product in a blend of chitosan and carboxymethylated guar gum, a synthetic caviar with better mechanical strength and heat resistance can be obtained.

[0058] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A method for preparing high-temperature resistant synthetic caviar for pets, characterized in that, Includes the following steps: The wall material solution is prepared by mixing the guar gum solution and the sodium alginate solution evenly. Calcium solution, acid solution, emulsifier, suspending agent and nutrients are mixed evenly to prepare mixed adhesive solution. Mix the mixed adhesive solution with edible oil and cut to prepare core material adhesive solution. The core material adhesive solution is dropped into the wall material solution and reacted for 5-10 minutes. After separation, washing, sterilization, and packaging, synthetic caviar is obtained.

2. The method for preparing high-temperature resistant synthetic caviar for pets according to claim 1, characterized in that: The wall material solution also contains nanocellulose and polyvinyl alcohol, with the mass ratio of sodium alginate, nanocellulose and polyvinyl alcohol being 2:1-1.4:1.1-1.

5.

3. The method for preparing high-temperature resistant synthetic caviar for pets according to claim 1, characterized in that: The polyvinyl alcohol is PEG2000 or PEG4000.

4. The method for preparing high-temperature resistant synthetic caviar for pets according to claim 2, characterized in that: The following pretreatment is performed after washing and before sterilization: Carboxymethylated guar gum and chitosan were dissolved separately to prepare carboxymethylated guar gum solution and chitosan solution; A blend was prepared by mixing carboxymethylated guar gum solution and chitosan solution. Add the washed product to the blending solution, circulate and soak 2-3 times, then remove the washed product.

5. The method for preparing high-temperature resistant synthetic caviar for pets according to claim 4, characterized in that: The concentration of the carboxymethylated guar gum is 3-5 wt%; the concentration of the chitosan solution is 3-5 wt%.

6. The method for preparing high-temperature resistant synthetic caviar for pets according to claim 4, characterized in that: The volume ratio of the carboxymethylated guar gum solution to the chitosan solution is 1:1-3.

7. The method for preparing high-temperature resistant synthetic caviar for pets according to claim 1, characterized in that: The concentration of the guar gum solution is 1-5 wt%, the concentration of the sodium alginate solution is 0.8-2 wt%, and the volume ratio of the guar gum solution to the sodium alginate solution is 0.8-1.2:

1.

8. The method for preparing high-temperature resistant synthetic caviar for pets according to claim 1, characterized in that: The ratio of the calcium solution, acid solution, and suspending agent is 1-1.5:1-1.5:0.8-1.2; The amount of emulsifier used is 1‰-3‰ of the mass of the core material adhesive; The ratio of the mixed adhesive solution to edible oil is 2-3:7-8.

9. The method for preparing high-temperature resistant synthetic caviar for pets according to claim 1, characterized in that: The concentration of the calcium solution is 3-10 wt%, and the calcium source is at least one of calcium chloride, calcium lactate, and calcium carbonate. The concentration of the suspending agent is 0.3-0.8 wt%, and the suspending agent is selected from at least one of xanthan gum aqueous solution, locust bean gum aqueous solution, and prickly pear gum aqueous solution; The acid concentration is 3-10 wt%, and it is selected from at least one of hydrochloric acid, acetic acid, and gluconolactone.

10. The method for preparing high-temperature resistant synthetic caviar for pets according to claim 1, characterized in that: The edible oil is selected from at least one of corn oil, soybean oil, and olive oil; The nutrient is at least one of lutein, fish oil, krill oil, and astaxanthin.

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