A method for preparing a surimi-based material suitable for high-temperature microwave 3D printing

Abstract

The application discloses a preparation method of a surimi-based material suitable for high-temperature microwave 3D printing, and belongs to the technical field of surimi processing processes. In the application, heat-reversible gelatin and kappa-carrageenan are dispersed in water, and then surimi is added for chopping and mixing. The surimi product of the microwave 3D printing has good instant curing properties and superior forming capacity, and greatly reduces the deformation of the microwave 3D printing product. Compared with traditional printing materials, the preparation method of the microwave 3D printing material realizes the microwave 3D printing of the slurry at 80 DEG C, and solves the problems of TG enzyme dependence and limited printable microwave power in the original microwave 3D printing process.

Description

Technical Field

[0001] This invention relates to the field of food 3D printing technology, and in particular to a method for preparing a material based on surimi suitable for high-temperature microwave 3D printing. Background Technology

[0002] Surimi is a high-protein, low-fat food processing raw material rich in various nutrients. After salting and chopping, it exhibits good flowability and solid-like properties, thus providing a prerequisite for developing 3D printing technology. In existing surimi 3D printing processes, the slurry inevitably undergoes deformation during stacking and post-processing, resulting in poor structural support in the printed product. Furthermore, the lack of slurry solidification prevents the printing of complex hollow structures. The publicly disclosed CN 111248474A solution addresses this by developing a microwave 3D printing technology, significantly improving the slurry's molding quality. The publicly disclosed CN 109820224 A solution achieves initial extrusion and curing of the surimi slurry by adjusting the positional relationship between the slurry extruder and the microwave heating probe, effectively enhancing the 3D printing performance of the surimi slurry.

[0003] However, in the above methods, the solidification and gelation process of the slurry mainly relies on the TG enzyme, without fully utilizing the thermal gelation response of the surimi itself. Furthermore, due to the unavoidable fluctuation in the output power of the microwave, the surimi will clog the pipeline within a narrow temperature range of around 40°C, limiting the printable microwave power and achievable printing temperature. The lower printing temperature cannot meet the food safety standards for food production. Therefore, in order to solve the above problems of microwave 3D printing of surimi, it is urgent to develop a material preparation method based on surimi suitable for high-temperature microwave 3D printing. Summary of the Invention

[0004] To address the aforementioned problems in existing technologies, this invention provides a material preparation method based on surimi suitable for high-temperature microwave 3D printing. This invention uses surimi, which has good flowability and significant thermogelation properties, as a base. Through the phase transition and coupling of thermally reversible hydrocolloids, it aims to control the gelation process of surimi during microwave 3D printing, achieving higher-temperature microwave 3D printing, overcoming temperature fluctuation limitations and TG enzyme dependence. Furthermore, it utilizes the cooling gelation properties of thermally reversible hydrocolloids to achieve rapid gelation of the extruded slurry, improving the curing properties of the printed product, with the goal of obtaining microwave 3D printed products with dense structures and good gel strength.

[0005] The technical solution of the present invention is as follows:

[0006] The first objective of this invention is to provide a method for preparing a fish surimi-based material suitable for high-temperature microwave 3D printing, comprising the following steps: each raw material is in parts by weight;

[0007] (1) Mix 100-600 parts of thermally reversible colloid and 3500-4500 parts of water at 2-10℃ and stir evenly to obtain a prehydrated colloid; the thermally reversible colloid is a mixture of gelatin and κ-carrageenan.

[0008] (2) Take 4000-6000 parts of fish paste and 200-400 NaCl and place them in a vacuum chopper to chop and mix to obtain fish paste slurry A;

[0009] (3) Add the hydrated colloid obtained in step (1) to the surimi slurry A obtained in step (2), and continue to chop for 5 minutes to obtain the material suitable for high temperature microwave 3D printing; store at 2-10℃ for later use.

[0010] In one embodiment of the present invention, in step (1), the gel strength of the gelatin is 150-300 Bloomg.

[0011] In one embodiment of the present invention, in step (1), the prehydrated colloid is prepared by mixing 150 parts of gelatin, 450 parts of κ-carrageenan and 4100 parts of water.

[0012] In one embodiment of the present invention, in step (1), the stirring conditions are: stirring at 3000-4000 rpm for 1-6 minutes at 2-25°C.

[0013] In one embodiment of the present invention, in step (2), the fish paste is one of the following: golden threadfin bream fish paste, silver carp fish paste, copper basin fish paste, ribbonfish fish paste, grass carp fish paste, and black carp fish paste; the moisture content of the fish paste is 76-80%.

[0014] In one embodiment of the present invention, in step (2), the fish paste is fish paste frozen at -18°C placed in a 4°C refrigerator to thaw for 8 hours, and then cut into 3×3×3 cubic pieces to obtain small pieces of fish paste.

[0015] In one embodiment of the present invention, in step (2), surimi self-gel is defined as a semi-solid or solid that loses its original fluidity and becomes a semi-solid or solid with obvious hardness, and its gel strength is 100-400 g·cm.

[0016] If the fish paste gels due to excessive thawing time, replace the fish paste.

[0017] In one embodiment of the present invention, in step (2), the chopping conditions are: temperature of 2-10℃, vacuum degree of -0.2 to -0.6 bar, rotation speed of 1500-4500 rpm, and time of 1-5 min.

[0018] In one embodiment of the present invention, in step (3), the gelatin content in the material suitable for high-temperature microwave 3D printing is 1.5 wt%, and the κ-carrageenan content is 4.5 wt%.

[0019] A second objective of this invention is to provide a fish paste-based material suitable for high-temperature microwave 3D printing prepared by the above-described method.

[0020] A third objective of this invention is to provide an application of the above-mentioned surimi-based material suitable for high-temperature microwave 3D printing, for use in 3D printing food.

[0021] The fourth objective of this invention is to provide a method for printing food using the aforementioned material suitable for high-temperature microwave 3D printing, comprising the following steps:

[0022] The above-mentioned material, stored at low temperature (2-10℃), is used as printing paste and loaded into the printer syringe. The printing syringe is centrifuged to ensure that air bubbles are completely removed from the printing syringe.

[0023] The printing program is started. The microwave 3D printer prints the printing paste layer by layer on the work platform according to the pre-designed model parameters. The printing paste is extruded by adjusting the printing nozzle diameter to 0.8-1.2mm, the single layer height to 0.8-1.2mm, and the printing speed to 35-45mm / s.

[0024] Under the control of the control system and microwave source, microwaves are output at a frequency of 2450MHz with an output power of 0-100W. The temperature of the printing paste at the printing nozzle is monitored by a thermal imager and is 10-90℃. After the printing paste is extruded from the printing nozzle, the paste, which is freed from the microwave thermal effect, has a large temperature difference between itself and room temperature. Furthermore, the thermally reversible colloid has cooling gel properties, which allows the printing paste to solidify instantly during the stacking process without the need for additional cooling and solidification methods. This results in fish paste-based food suitable for high-temperature microwave 3D printing.

[0025] In one embodiment of the present invention, the printing needle is centrifuged at 300-600 rpm for 3-6 min at a centrifugation temperature of 2-10℃.

[0026] In one embodiment of the present invention, the nozzle diameter is 1.0 mm, the single layer height is 1.0 mm, and the printing speed is 40 mm / s.

[0027] In one embodiment of the present invention, the preset model parameters are:

[0028] 1) Cylindrical model: 30mm in both diameter and height;

[0029] 2) Hollow sphere model: inner diameter is 23mm, outer diameter is 35mm, and height is 29mm.

[0030] In one embodiment of the present invention, the printing environment temperature is maintained at room temperature (10-25°C).

[0031] In one embodiment of the present invention, the filling density of the cylindrical model is 60-80%, and that of the hollow sphere model is 0-5%, with straight lines used for filling.

[0032] In a preferred embodiment of the present invention, the microwave power and slurry temperature need to be flexibly adjusted according to the material properties during the microwave 3D printing process. When the microwave power is set too high, it is easy to cause over-curing of the material and overheating and deformation of the printing nozzle, which significantly reduces the printing effect of the microwave 3D printed product. When the microwave power is set too low, the self-gelling property of the slurry cannot be utilized, which significantly reduces the molding quality of the microwave 3D printed product.

[0033] The beneficial technical effects of this invention are as follows:

[0034] (1) This invention is based on surimi, which has good flowability and obvious thermogelation properties. A material suitable for high-temperature microwave 3D printing is obtained by adding a thermally reversible hydrocolloid to the surimi slurry. Then, a microwave 3D printer is used for printing. The phase change and coupling of the thermally reversible hydrocolloid are utilized to control the gelation process of the surimi during microwave 3D printing, thereby achieving microwave 3D printing at 80℃. During microwave 3D printing, the thermally reversible hydrocolloid gradually melts under the action of heat energy. Because the three-dimensional network structure of the colloidal molecules is destroyed, its ability to bind water decreases. Free water affects the cross-linking between surimi proteins. Simultaneously, after the colloidal sol is dissolved, it disperses in a liquid state between the surimi, hindering the aggregation of surimi proteins, thus slowing down the gelation process of the surimi, allowing the surimi to be smoothly extruded even at higher temperatures. After microwave 3D printing, the slurry cools and gels during the stacking process, significantly improving the curing effect of the printed product.

[0035] The present invention provides a microwave 3D printing raw material control scheme based on surimi suitable for higher printing temperatures, which effectively overcomes the temperature limitations and TG enzyme dependence of existing microwave 3D printing. It not only endows printed products with superior molding capabilities, but also provides a new model for future food manufacturing.

[0036] (2) This invention can give the surimi slurry good rheological properties and enable microwave 3D printing under high temperature conditions. When the microwave output power is 42W, the temperature of the slurry at the printing nozzle is monitored by a thermal imager as 80°C. After printing, the slurry uses the temperature difference between itself and room temperature to achieve instant solidification during the stacking process. The high-temperature microwave 3D printed product printed at 80°C has high gel strength, good resistance to deformation, and the overall structure of the printed sample is compact with no obvious particles on the surface.

[0037] (3) This invention enables surimi slurry to maintain good viscosity and solid-like properties during high-temperature microwave 3D printing, allowing the slurry to be extruded smoothly and solidified instantly through high-temperature microwave 3D printing. The printed product has a high gel strength of up to 423.51 g·cm and good resistance to deformation. It is suitable for 3D printing with complex hollow three-dimensional structures, such as hollow spheres: the product with good appearance and hollow structure is successfully printed. The structure of the printed hollow sphere is complete and the height is close to that of the model. After cutting the hollow sphere structure, the hollow structure does not collapse and can still maintain the integrity of its shape when subjected to 100g pressure.

[0038] (4) The method of the present invention is simple and easy to operate, requires no addition of enzyme preparations, is economical and affordable, and conforms to the concept of green and healthy food; it provides a new model for future food manufacturing. Attached Figure Description

[0039] Figure 1 To illustrate the rheological properties of the printing material in Comparative Example 1 at different temperatures;

[0040] Figure 2 The printing performance of microwave 3D printing on the printing material of Comparative Example 1 is shown.

[0041] Figure 3 The instant curing performance of the printing material in Comparative Example 1 for microwave 3D printing;

[0042] Figure 4 The instant curing performance of conventional TG-enzyme-added fish paste for microwave 3D printing was compared with that of Comparative Example 2.

[0043] Figure 5 To compare the printing performance of the printing materials in Comparative Example 3 and Example 1 using microwave 3D printing;

[0044] Figure 6 The printing performance of the printing material in Example 2 for microwave 3D printing;

[0045] Figure 7 Instant curing properties of the printing material used in Example 2 for microwave 3D printing;

[0046] Figure 8 The rheological properties of microwave 3D printed products prepared with different amounts of gelatin and κ-carrageenan in Example 2 are shown. Detailed Implementation

[0047] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0048] The microwave 3D printer involved in the embodiments and comparative examples of this invention is: a microwave 3D printer (XOM-3D, Nanjing Xianou Instrument Manufacturing Co., Ltd.); main components: a 3D printing cylinder coupled to the microwave heating cavity, a 3D printer, a microwave source and a control system; microwave frequency: 2450MHz; maximum microwave output power: 400W / g; maximum heating temperature: 260℃.

[0049] The frozen fish paste was provided by Fujian Anjing Food Co., Ltd., and was thawed in the refrigerator (4℃) for 8 hours before testing.

[0050] κ-carrageenan was purchased from Shanghai Aladdin Reagent Co., Ltd.

[0051] Gelatin (Bloom value 180) was purchased from Beijing Yikeno Reagent Co., Ltd.

[0052] The test methods involved in the embodiments and comparative examples of this invention are as follows:

[0053] 1. Setting microwave 3D printing parameters:

[0054] The 3D printing parameters are set as follows: nozzle diameter, 1.0 mm; layer height, 1.0 mm; extrusion flow rate, 120%; infill density, 0% (80% for cylindrical samples, using straight lines for pattern filling); printing speed, 40 mm / s; microwave frequency, 2450 MHz.

[0055] 2. Microwave 3D Printing Performance Test:

[0056] A cylindrical model with a height of 30mm and a radius of 15mm was selected for microwave 3D printing. The microwave output power was adjusted to achieve different temperatures for the slurry inside the 3D printing extruder, and the temperature of the extruded slurry was monitored using a thermal infrared imager. The printable temperature is defined as the temperature at which the slurry can smoothly pass through the printing extruder and stack according to the preset model, without the resulting printed product exhibiting negative issues such as misalignment or deformation.

[0057] 3. Product gel strength test:

[0058] A cylindrical model with a height of 30 mm and a radius of 15 mm was selected for microwave 3D printing. Immediately after microwave 3D printing, the cylindrical sample was placed on the testing platform of a texture analyzer to determine its gel strength. A fixed trigger strength of 5 g was set, and a P / 5s spherical probe was used to vertically pierce the cylinder at pre-test speeds of 1, 1, and 2 mm / s, and post-test speeds of 1 mm / s, with a maximum displacement of 15 mm. The breaking force (g) was defined as the force value of the first peak on the force-deformation curve. The breaking distance (mm) was the height between the initial contact point and the first force peak. The gel strength was defined as breaking force × breaking distance.

[0059] 4. Product instant curing performance test:

[0060] A hollow sphere model with an inner diameter of 23mm, an outer diameter of 35mm, and a height of 29mm was selected for microwave 3D printing. Immediately after microwave 3D printing, the printed hollow sphere was placed in a photography studio for photographing, and its height was recorded. Then, the hollow sphere was cut in half, photographed, and its height recorded. Subsequently, 20g, 50g, and 100g weights were placed on the cut hollow spheres, and the height was recorded again.

[0061] 5. Rheological property testing of microwave 3D printed products using fish paste containing gelatin and κ-carrageenan:

[0062] The rheological properties of the slurry were determined using a DHR-3 shear rheometer (TA Instruments, USA), using parallel plates with a diameter of 40 mm. Prior to testing, the printing slurry was stored in an ice box to inhibit self-gelling. During sample loading, the platform temperature was maintained at 20°C. During testing, the distance between the two plates was maintained at 1000 mm, and silicone oil was applied to the outer edges to prevent moisture migration. Tests (except for temperature scans) were conducted at temperatures of 20, 40, 45, 50, 60, and 80°C. Viscosity tests were performed from 0.1 to 100 s. -1 The shear rates were measured. Storage modulus (G') and loss modulus (G”) were measured at 1% strain and angular frequency variations of 0.1–100 rad / s. During the temperature scan, the frequency was set to 10 rad / s and the strain to 1%, and the changes in G' and G” were recorded as the temperature rose (or fell) from 20 °C to 90 °C.

[0063] Example 1

[0064] A method for preparing a fish paste-based material suitable for high-temperature microwave 3D printing, the specific steps of which are as follows: raw materials are in parts by weight;

[0065] (1) Take 150 parts of gelatin, 450 parts of κ-carrageenan and 4100 parts of water respectively, mix the three at 10°C, and then stir at 3600 rpm for 5 minutes until fully mixed to obtain a prehydrated colloid; then store at 2°C for later use.

[0066] (2) Take 5000 parts of diced fish paste and 300 parts of NaCl and place them in a vacuum chopper. Set the chopping temperature of the vacuum chopper to 4℃ and the vacuum degree to -0.4 bar. Chop at 4500 rpm for 1 min to obtain fish paste slurry A. The fish paste is golden threadfin fish paste with a moisture content of 78%.

[0067] (3) Add the prehydrated colloid to the fish paste A in the vacuum chopper and continue chopping at 4500 rpm for 5 min to obtain a fish paste-based material suitable for high-temperature microwave 3D printing (fish paste protein content is 13wt%), and store it at 4℃ for subsequent printing steps.

[0068] The application of the above-mentioned fish paste-based material suitable for high-temperature microwave 3D printing in microwave 3D printing follows these steps:

[0069] The fish paste-based material suitable for high-temperature microwave 3D printing obtained in step (3) is loaded into the barrel of the microwave 3D printer. The centrifugation temperature is set to 4℃, and the material is centrifuged at 500rpm for 5min to remove air bubbles in the printing needle. The printing program is started. The microwave 3D printer prints the printing paste layer by layer on the work platform according to the preset model parameters (cylindrical model: height 30mm, radius 15mm; hollow sphere model: inner diameter 23mm, outer diameter 35mm, height 29mm). By adjusting the nozzle diameter to 1.0mm, the single layer height to 1.0mm, the printing speed to 40mm / s, and the microwave output power to 42W / g, the printing paste is extruded and initially formed at 80℃.

[0070] The experimental results showed that the method based on Example 1 can realize the microwave 3D printing process at 80°C and achieve instant curing of the printing slurry: the printed cylindrical structure is compact and there are no obvious large particles on the surface; the printed hollow sphere has a complete shape and structure, and its height is close to that of the model. The upper layer of the hollow structure did not collapse and can withstand 100g of pressure after cutting; this proves that the slurry changes from a viscoelastic fluid to an elastic solid gel during the microwave 3D printing process, and instant curing of the slurry is achieved.

[0071] Comparative Example 1: Printing material without added gelatin and κ-carrageenan

[0072] Same as Example 1, except that gelatin and κ-carrageenan were not added to the printing material.

[0073] The printing material prepared in Comparative Example 1 was used in microwave 3D printing to test its microwave 3D printing performance. Corresponding printed products were prepared and the gel strength of the products was measured to evaluate the instant curing performance of the slurry.

[0074] Experimental results show that the fish paste without added gelatin and κ-carrageenan can be smoothly extruded at a microwave power of up to 9 W / g (45℃), but the printed products cannot maintain stacking at this level. When the microwave output power exceeds 9 W / g, the fish paste gels inside the extruder, causing blockage of the pipes and preventing smooth extrusion of the printing paste. The gel strength of the cylindrical products printed at 6 W / g (40℃) is only 53.25 g·cm, and the hollow spheres collapse immediately after being cut, failing to maintain the original hollow structure. This indicates that the fish paste without added gelatin and κ-carrageenan does not achieve immediate curing during microwave printing at a microwave power of 6 W / g.

[0075] from Figure 1 It can be seen that as the printing temperature increases, the viscosity of the fish paste increases, exhibiting thermal gelation behavior, which clogs the extrusion nozzle and prevents the printing process from continuing. Simultaneously, the tanδ value of the fish paste decreases, indicating enhanced solid-like properties, with high temperature promoting the formation of fish paste gel. The printing performance of the material in Comparative Example 1 for microwave 3D printing is as follows: Figure 2 As shown; the instant curing properties of the printing material in Comparative Example 1 for microwave 3D printing are as follows: Figure 3 As shown in Table 1, the gel strength of the product printed using the printing material of Comparative Example 1 using microwave 3D printing is shown in Table 1 below.

[0076] Table 1

[0077]

[0078] Comparative Example 2: Traditional fish paste with added transglutaminase (TG enzyme)

[0079] Following the method described in the published article "Synergistic effect of microwave 3D print and transglutaminase on the self-gelation of surimi during printing", a surimi slurry with an added 5 U / g TG enzyme was obtained;

[0080] Comparative Example 2, a conventional surimi slurry with added TG enzyme, was used in microwave 3D printing in accordance with the application of the surimi-based material suitable for high-temperature microwave 3D printing in Example 1. The aim was to test the microwave 3D printing performance of the slurry, prepare corresponding printed products, and measure the gel strength of the products to evaluate the instant curing performance of the slurry.

[0081] Experimental results show that traditional surimi slurry with added TG enzyme can be smoothly extruded at a microwave power of up to 6W / g, and at this power, the surimi slurry can achieve instant curing. When the microwave output power is 6W / g, the temperature of the surimi inside the extruder reaches 40℃, and the slurry can be quickly extruded and cured on the printing platform. As the power increases, the proportion of the high-temperature region (>40℃) inside the extruder gradually increases, which increases the activity of TG enzyme inside the extruder. At the same time, the high temperature also increases the viscosity of the surimi, leading to blockage and preventing the printing slurry from being extruded smoothly. This indicates that traditional surimi slurry with added TG enzyme can achieve instant curing of the slurry during microwave printing at a microwave power of 6W / g, but the microwave 3D printing process depends on TG enzyme, and the printable microwave power is limited. The gel strength of the product microwave 3D printed from the traditional surimi slurry with added TG enzyme in Comparative Example 2 is shown in Table 2 below; the instant curing performance of the traditional surimi slurry with added TG enzyme in Comparative Example 2 microwave 3D printing is shown in Table 2 below. Figure 4 As shown.

[0082] Table 2

[0083]

[0084]

[0085] Comparative Example 3

[0086] A method for preparing a 3D printing material based on surimi, the specific steps of which are as follows: raw materials are in parts by weight;

[0087] Same as Example 1, except that step (1) is: take 150 parts of gelatin, 450 parts of κ-carrageenan and 4100 parts of water respectively, stir the three in a 90°C water bath at 300 rpm for 30 minutes until fully mixed, and obtain a pre-hydrated colloid, and keep it in a 40°C water bath for later use.

[0088] The printing material prepared in Comparative Example 2 was used for microwave 3D printing to test its microwave 3D printing performance. The results are as follows: Figure 5 As shown in Table 3, the gel strength test results of the corresponding printed products are as follows.

[0089] Table 3

[0090]

[0091] from Figure 5It can be seen that both colloid addition methods can achieve microwave 3D printing at 42W / g (80℃). However, the surface of the sample printed by the hot water sol group is very rough and the graininess is obvious. This is mainly because the melted liquid colloid re-gels during the low-temperature chopping process and disperses in the surimi slurry in the form of large particles. This leads to the phenomenon of discontinuous extrusion of the slurry during microwave 3D printing. In contrast, the colloid in the pre-hydrated colloid group is evenly distributed and the particles are small. Therefore, the surface of its printed product is relatively smooth and the structure is more compact.

[0092] As shown in Table 3, all printed products after high-temperature microwave 3D printing exhibited good gel strength, and the gel strength increased significantly with increasing printing temperature. The pre-hydrated gel group showed the highest gel strength (up to 423.51±7.63 g·cm) after microwave 3D printing, proving that the pre-hydrated gel group not only obtained printed samples with better shapes but also achieved instant curing of the slurry.

[0093] Example 2

[0094] A method for preparing a fish paste-based material suitable for high-temperature microwave 3D printing, the specific steps of which are as follows: raw materials are in parts by weight;

[0095] Same as Example 1, except that different fractions of gelatin and κ-carrageenan, 4100 parts of water were taken respectively, and the three (or two) were stirred at 3600 rpm for 5 minutes at 20°C until fully mixed to obtain a prehydrated colloid, which was then stored in a refrigerator at 4°C for 10 hours.

[0096] The materials prepared in Example 2 with different amounts of colloid addition, suitable for high-temperature microwave 3D printing, were used for microwave 3D printing. Their microwave 3D printing performance was as follows: Figure 6 As shown, Figure 6 In this context, 6G refers to printing materials with 6% gelatin added; 6K refers to printing materials with 6% κ-carrageenan added; 4.5G / 1.5K refers to printing materials with 4.5% gelatin and 1.5% κ-carrageenan added; 3G / 3K refers to printing materials with 3% gelatin and 3% κ-carrageenan added; and 1.5G / 4.5K refers to printing materials with 1.5% gelatin and 4.5% κ-carrageenan added. The instant curing properties of the printing materials for microwave 3D printing are as follows: Figure 7 As shown in Table 4 (significance level of height difference between samples is indicated by lowercase letters, p<0.05); the corresponding printed products were prepared and the gel strength of the products was measured.

[0097] Table 4

[0098]

[0099] from Figure 6It can be seen that printing materials with 6% gelatin and 6% κ-carrageenan can be extruded smoothly at higher extruder temperatures, but the increase in printable temperature is limited. When the microwave power is 13W / g, the extruder temperature of the 6G slurry reaches 50℃. The gelatin detaches from the surimi gel in a liquid state, reducing its water-binding capacity. This water release affects the cross-linking between surimi proteins, resulting in a soft texture, collapse, and deformation in the printed product. When the extruder temperature of the 6K slurry reaches 50℃, although the κ-carrageenan in this state has a certain viscosity and fluidity, the surimi gelation dominates the slurry, causing the extruded filaments to still bend and deform, preventing the printed sample from maintaining a good shape. All printing materials with added mixed colloids show a significant increase in printable temperature, with the highest extruder temperature reaching 80℃. Under high-temperature conditions, the slurry can be smoothly extruded and stacked into the preset model shape, but the surface of the printed sample becomes rough with a clear granular texture. In the 4.5G / 1.5K group, the higher gelatin content caused the molten gelatin to encapsulate the surimi gel during extrusion, resulting in uneven extrusion and a granular surface, making the surface particles the most noticeable. In contrast, the 1.5G / 4.5K sauce had the optimal gelatin and κ-carrageenan content. Under these conditions, the printing material could be smoothly extruded at high temperatures and rapidly solidified during stacking, resulting in a compact overall structure with no obvious particles on the surface.

[0100] Table 4 shows that the gel strength of the surimi-printed products increases with increasing temperature. The 1.5G / 4.5K group exhibits the highest gel strength at 80℃, reaching 423.51 g·cm⁻¹. Furthermore, under high-temperature conditions, the gel strength shows a clear dependence on κ-carrageenan concentration, indicating that a high κ-carrageenan content can result in higher network density and stability in the surimi-printed products. However, excessively high κ-carrageenan content leads to excessively high printing paste viscosity, which can easily cause nozzle clogging.

[0101] from Figure 7 It can be seen that pure surimi products without gelatin and κ-carrageenan exhibit severe deformation after cutting due to the hollow structure inside the printed spheres. However, the composite colloid with added gelatin and κ-carrageenan significantly improves the molding quality of the products, reduces deformation after cutting, produces a flatter cut surface, and decreases adhesion to the cutting blade, especially for products printed at 80℃. Applying different forces to each printed product after cutting the hollow sphere structure further evaluates the deformation resistance of microwave 3D printed products. The results show that at 20℃, different weights of weights caused varying degrees of collapse in the hollow spheres. For both 3G / 3K and 1.5G / 4.5K, products printed at 80℃ can withstand a 100g external force. The 1.5G / 4.5K group exhibits the smallest height change, indicating its optimal mechanical properties.

[0102] from Figure 8 It can be seen that at high temperatures, the viscosity of surimi slurry increases with increasing κ-carrageenan content, and the rheological properties of the surimi slurry are significantly enhanced. The increase in G' of the surimi slurry indicates that the slurry's supporting properties are improved, which is beneficial for maintaining its shape during stacking.

[0103] The embodiments provided above are not intended to limit the scope of the invention, nor are the described steps intended to limit the order of execution. Any obvious modifications made to the invention by those skilled in the art based on existing common knowledge also fall within the scope of protection defined by the claims.

Claims

1. A method for preparing a fish paste-based material suitable for high-temperature microwave 3D printing, characterized in that, The preparation method includes the following steps: each raw material is measured in parts by weight; (1) Mix 150 parts of gelatin, 450 parts of κ-carrageenan and 4100 parts of water at 2-25℃ and stir until homogeneous to obtain a prehydrated colloid; (2) Take 4000-6000 parts of fish paste and 200-400 parts of NaCl and place them in a vacuum chopper to chop and mix to obtain fish paste slurry A; (3) Add the prehydrated colloid obtained in step (1) to the surimi slurry A obtained in step (2), and continue to chop for 5 minutes to obtain the material suitable for high temperature microwave 3D printing; store at 2-10℃ for later use.

2. The preparation method according to claim 1, characterized in that, In step (1), the gel strength of the gelatin is 150-300 Bloom g.

3. The preparation method according to claim 1, characterized in that, In step (1), the stirring conditions are: stirring at a speed of 3000-4000 rpm for 1-6 minutes.

4. The preparation method according to claim 1, characterized in that, In step (2), the fish paste is one of the following: golden threadfin bream fish paste, silver carp fish paste, copper basin fish paste, ribbonfish fish paste, grass carp fish paste, and black carp fish paste; the moisture content of the fish paste is 76-80%.

5. The preparation method according to claim 1, characterized in that, In step (2), the fish paste is frozen at -18℃ and then thawed in a 4℃ refrigerator for 8 hours. It is then cut into 3×3×3 cubic pieces to obtain small pieces of fish paste.

6. The preparation method according to claim 1, characterized in that, In step (2), the chopping conditions are: temperature 2-10℃, vacuum degree -0.2~-0.6 bar, rotation speed 1500-4500 rpm, and time 1-5 min.

7. A fish surimi-based material suitable for high-temperature microwave 3D printing, prepared by the method according to any one of claims 1-6.

8. An application of the fish paste-based material of claim 7 suitable for high-temperature microwave 3D printing, characterized in that, Used for 3D printing food.

9. A method for printing food using a fish paste-based material suitable for high-temperature microwave 3D printing as described in claim 7, characterized in that, Includes the following steps: Fish paste-based material suitable for high-temperature microwave 3D printing, stored at 2-10℃, is used as printing slurry and loaded into the printer's matching printing syringe. The printing syringe is then centrifuged at 300-600 rpm for 3-6 minutes at a temperature of 2-10℃. The printing program is started. The microwave 3D printer prints the printing paste layer by layer on the work platform according to the pre-designed model parameters. The printing paste is extruded by adjusting the printing nozzle diameter to 0.8-1.2mm, the single layer height to 0.8-1.2mm, and the printing speed to 35-45mm / s. Under the control of the control system and microwave source, microwaves are output at a frequency of 2450MHz with an output power of 42 W / g. The temperature of the slurry at the printing nozzle is monitored by a thermal imager and found to be 80℃. After the printing slurry is extruded from the printing nozzle, the slurry, which is free from the microwave thermal effect, can achieve instant curing of the slurry during the stacking process without the aid of additional cooling and curing methods due to the temperature difference between the slurry and room temperature, and the cooling gel properties of the thermally reversible colloid. This results in a fish paste-based food suitable for high-temperature microwave 3D printing.

10. The method according to claim 9, characterized in that, The printing environment temperature should be maintained between 10-25℃.

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