3D printing ink based on pea protein isolate as well as preparation method and application of 3D printing ink

Abstract

The invention provides 3D printing ink based on pea protein isolate and a preparation method and application thereof, and relates to the field of artificial foods.The 3D printing ink based on the pea protein isolate is prepared from, by mass, 10%-20% of modified pea protein isolate modified through cold argon plasma, 0.2%-1% of affinity colloid, 0.5%-1% of sodium carboxymethylcellulose, 5%-10% of edible oil and the balance water. The concentration of sodium chloride in the sodium chloride aqueous solution is 0.5-1%, and the affinity colloid is xanthan gum or carrageenan. Compared with existing ink, the 3D printing ink has higher apparent viscosity and a more compact gel network structure, and artificial food printed by using the ink has higher mechanical performance and has great application potential.

Description

Technical Field

[0001] The present invention relates to the field of artificial food technology, and in particular to a 3D printing ink based on pea protein isolate, and a preparation method and application thereof. Background Art

[0002] Artificial meat is divided into two types: plant meat and cell meat. Currently, plant meat is more popular on the market. Plant meat usually contains less saturated fat and cholesterol, and can provide high-quality protein and dietary fiber, which may be beneficial for maintaining a balanced bacterial flora and have a positive impact on overall health. It is regarded as a healthier meat substitute.

[0003] There are many different processing technologies for preparing plant meat, mainly including electrospinning, high / low moisture extrusion technology, hot shear technology, and 3D printing technology. Spinning technology has high requirements for protein solutions and will produce a large amount of chemical waste liquid; extrusion technology cannot meet the needs of different groups of people well. Plant meat 3D printing technology is based on the application and development of traditional 3D printing technology in the food field. Due to its high precision and wide material versatility, it has been widely used in the food industry and has better development prospects. For example, the Chinese invention patent with publication number CN109251492A discloses a biocompatible ink for 3D printing, which contains a mixture of synthetic degradable polymers and natural polymers. However, there are still some problems in the preparation of plant meat by 3D printing technology, including: the extrusion force of the extrusion-based 3D printer when applied to plant meat is low, and the plant-based artificial meat ink with high hardness is difficult to extrude, so it is difficult to imitate the texture of animal meat. At the same time, the existing printing ink for plant meat 3D printing cannot support and / or provide a fine 3D printing process. Therefore, it is necessary to develop a low-cost, simple to prepare, and fine printing 3D printing ink. Summary of the invention

[0004] The purpose of the present invention is to provide a 3D printing ink which is low-cost, easy to prepare and can be used for fine printing.

[0005] To achieve the above object, the first aspect of the present invention provides a 3D printing ink based on pea protein isolate, characterized in that it comprises the following raw materials in parts by weight: 10-20% of modified pea protein isolate modified by cold argon plasma, 0.2-1% of affinity colloid, 0.5-1% of sodium carboxymethyl cellulose, 5-10% of edible oil, and the balance is a sodium chloride aqueous solution with a sodium chloride concentration of 0.5-1%, wherein the affinity colloid is xanthan gum or carrageenan.

[0006] Pea Protein Isolate (PPI) is highly favored for its low cost, balanced amino acid ratio and high nutritional value, and is one of the main protein sources of plant meat. However, due to its low cysteine ​​content, the formation of disulfide bonds is affected, thereby affecting the network structure of the pea protein isolate gel. In the 3D printing ink based on pea protein isolate provided by the present invention, the protein raw material pea protein isolate is subjected to argon cold plasma modification, and the active substances generated by ionization are moderately oxidized and nitrosylated to modify the protein, causing changes in the protein structure, thereby enhancing its functional properties. The relevant functional properties are mainly reflected in the rheological properties, gelation and emulsification of the final product.

[0007] Xanthan gum, a polysaccharide produced by fermentation of Pseudomonas sp., can interact with positively charged proteins and modify the modified pea protein isolate.

[0008] Carrageenan is a hydrophilic sulfated polysaccharide extracted from seaweed with good film-forming ability, playing a prominent role in regulating gelling properties.

[0009] Sodium carboxymethyl cellulose, as a water-soluble cellulose derivative, forms composite particles with alcohol-soluble proteins, which can promote the formation of a dense gel network structure in the high internal phase Pickering emulsion and increase the apparent viscosity of the 3D printing ink.

[0010] The second aspect of the present invention provides a method for preparing the pea protein isolate-based 3D printing ink according to the first aspect, comprising the following steps: S1: modifying pea protein isolate by cold argon plasma to obtain modified pea protein isolate; S2: mixing the sodium chloride aqueous solution and the modified pea protein isolate to obtain a hydrated modified pea protein isolate; S3: adding affinity colloid and sodium carboxymethyl cellulose to the hydrated modified pea protein isolate solution, stirring evenly, adding edible oil, and high-pressure homogenization to obtain a gelatinized product; S4: The gelatinized material is heated and then cooled to 0-4° C. to obtain 3D printing ink.

[0011] Preferably, the step S1 comprises the following steps: S11: treating a 10-20% (w / w) pea protein isolate solution with a cold argon plasma jet; S12: After the cold argon plasma treatment is completed, the pea protein isolate solution is placed at 0-8° C. for cooling for 16-18 hours to obtain a modified pea protein isolate.

[0012] Preferably, in step S11, the parameters of the cold argon plasma jet treatment are: the height between the liquid surface and the nozzle is 8-12 mm, the standard flow rate is 2-5 L / min, and the power is 70-80 W.

[0013] Preferably, in step S11, the duration of the cold argon plasma jet treatment is 4 to 10 minutes.

[0014] Preferably, in step S2, the hydration temperature is 2-8°C.

[0015] Preferably, in step S3, the parameters of high-pressure homogenization are: rotation speed 7000-12000 r / min, and homogenization time 3-7 min.

[0016] Preferably, in step S4, the heating parameters are: heating temperature is 80-90° C., and heating time is 20-40 min.

[0017] The third aspect of the present invention provides an application of the pea protein isolate based 3D printing ink according to the first aspect, wherein the application is to use the pea protein isolate based 3D printing ink for the preparation of artificial meat.

[0018] Beneficial effects of the present invention: The present invention provides a new 3D printing ink based on pea protein isolate, which exhibits high apparent viscosity at low shear rates and has a denser gel network structure. At the same time, the structure of the ink is more stable than that of the prior art, and the mechanical strength of the artificial food prepared by the ink is also higher. In addition, the 3D printing ink based on pea protein isolate provided by the present invention has the advantages of low cost and simple preparation. The present invention also confirms the technical and economic feasibility of cold plasma as a food processing technology in the preparation of 3D printed artificial food, which provides enterprises with a high-quality plant meat production plan using pea protein as raw material, and provides a theoretical basis and technical support for enterprises to develop new products, and has great application potential. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is the apparent viscosity test result of the 3D printing ink based on pea protein isolate in a specific embodiment of the present invention; Figure 2 This is the frequency scanning result of the 3D printing ink based on pea protein isolate in a specific embodiment of the present invention; Figure 3 This is a photo of a 3D printed plant meat product using 3D printing ink based on pea protein isolate in a specific embodiment of the present invention; Figure 4 This is the low-frequency nuclear magnetic resonance result of the 3D printing ink based on pea protein isolate in a specific embodiment of the present invention; Figure 5 This is the X-ray diffraction result of the 3D printing ink based on pea protein isolate in a specific embodiment of the present invention; Figure 6 The molecular force test results of the 3D printing ink based on pea protein isolate in the specific embodiment of the present invention; Figure 7 The mechanical properties test results of the 3D printing ink based on pea protein isolate in a specific embodiment of the present invention. DETAILED DESCRIPTION

[0020] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below. It should be noted that the following embodiments are only used to illustrate the implementation method and typical parameters of the present invention, and are not used to limit the parameter range described in the present invention. Reasonable changes derived therefrom are still within the scope of protection of the claims of the present invention.

[0021] It should be noted that the endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed in this article.

[0022] Unless otherwise defined, all terms, symbols and other scientific terms used herein are intended to have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. In some cases, terms with conventionally understood meanings are defined herein for the purpose of clarification or ease of reference, and such definitions herein should not be construed as indicating significant differences from conventional understandings in the art. The technical methods described or cited herein are generally well understood by those skilled in the art and are adopted by conventional methods. Unless otherwise stated, the use of commercially available kits, reagents and instruments is carried out in accordance with the protocols and parameters given by the manufacturer.

[0023] Due to its high protein content and low allergenicity, pea protein will be more widely used as a soybean substitute, meeting the current consumer demand for alternative plant-based protein sources. Focusing on the new development direction of pea protein, developing means to enhance the functional and structural characteristics of pea protein, further expanding the scope of pea utilization, and developing more diversified and professional pea protein products are of great significance to enhancing the competitiveness of peas in the meat products industry.

[0024] As described in the background, currently known methods are unable to support and / or provide a fine 3D printing process that enables the fabrication of biologically complex scaffold structures. A simple, cost-effective, fine 3D printing protein-based ink is needed for food-oriented applications, including cultured meat production.

[0025] Based on this, a specific embodiment of the present invention provides a 3D printing ink based on pea protein isolate, and the 3D printing ink includes the following raw materials in parts by weight: 10-20% of modified pea protein isolate modified by cold argon plasma, 0.2-1% of affinity colloid, 0.5-1% of sodium carboxymethyl cellulose, 5-10% of edible oil, and the balance is a sodium chloride aqueous solution with a sodium chloride concentration of 0.5-1%, wherein the affinity colloid is xanthan gum or carrageenan.

[0026] The 3D printing ink based on pea protein isolate provided in the above embodiment is prepared by the following steps: S11: treating a 10-20% (w / w) pea protein isolate solution with a cold argon plasma jet, wherein the parameters of the cold argon plasma jet treatment are: a height between the liquid surface and the nozzle of 8-12 mm, a standard flow rate of 2-5 L / min, a power of 70-80 W, and a treatment time of 4-10 min; S12: After the cold argon plasma treatment is completed, the pea protein isolate solution is placed at 0-8° C. and cooled for 16-18 hours to obtain a modified pea protein isolate; S2: mixing the sodium chloride aqueous solution and the modified pea protein isolate at 2-8° C. to obtain a hydrated modified pea protein isolate; S3: adding affinity colloid and sodium carboxymethyl cellulose to the hydrated modified pea protein isolate solution, stirring evenly, adding edible oil, and using a high-pressure homogenizer at a speed of 7000-12000 r / min to gelatinize the mixture for 3-7 minutes; S4: The gelatinized material is heated at 80-90° C. for 20-40 min and then cooled to 0-4° C. to obtain a 3D printing ink.

[0027] The technical solution of the present invention is further described below through specific embodiments.

[0028] Terminology Note: PPI: Pea Protein Isolate; CP: cold plasma treatment; XG: xanthan gum; Car: carrageenan; CMC: sodium carboxymethyl cellulose.

[0029] Example 1 Preparation of 3D printing ink based on pea protein isolate Extraction of pea protein isolate: Soak fresh green peas at room temperature for 5-6 hours, peel them manually, and dry them in a 55°C oven. The dried green peas were crushed with a grinder and sieved through an 80-mesh sieve to form green pea powder. The green pea powder was mixed with n-hexane at a ratio of 1:5 (w / v), stirred at 1000 rpm for 2 hours, defatted 3-5 times, air-dried in a fume hood, and stored in a 4°C refrigerator. At room temperature, the defatted pea protein powder was dispersed in deionized water at a material-liquid ratio of 1:10 (w / v), 1M NaOH was added to adjust the pH to 9.00, and then stirred at 1000 rpm for 2 hours with a magnetic stirrer and the pH value was measured regularly to keep it constant. Centrifuged at 4°C, 8000 rpm, and 20 minutes, the supernatant was collected, the precipitate was taken, and the above operation was repeated. The pH of the supernatant collected twice was adjusted to 4.50 with 1M HCl, stirred at 1000 rpm for 2 h with a magnetic stirrer and the pH value was measured regularly to keep it constant. Centrifuged at 4°C, 8000 rpm, 20 min, the supernatant was removed, the precipitate was collected and re-dissolved in deionized water, and the pH was adjusted to 7.00 with 1M NaOH, and the pea protein was freeze-dried for 48 h. The protein content was determined by the Kjeldahl method and stored at -20°C for future use.

[0030] Cold argon plasma treatment: PPI was dispersed in 0.01M phosphate buffer (pH=7.00) to prepare 15% (w / w). The PPI solution was stirred at room temperature with a magnetic stirrer at 400rpm for 2h to prepare a PPI solution, which was placed in a 4°C refrigerator to fully dissolve. The PPI solution was taken out of the refrigerator and poured into a petri dish, placed on a lifting platform, and the height between the liquid level and the nozzle was adjusted to 10mm. The treatment was carried out under the conditions of a standard flow rate of 4L / min and a power of 80W. The treated PPI solution was placed in a 4°C refrigerator for 16~18h. Based on the results of the preliminary experiment, we selected PPI with a treatment time of 6min for subsequent experiments.

[0031] Preparation of 3D printing ink based on pea protein isolate: After preparing 1% NaCl solution with deionized water and stirring to dissolve, continue to add 15% (w / w) modified PPI powder or ordinary PPI powder, stir for 12 hours, and place in a 4°C refrigerator overnight to achieve hydration. At a certain temperature, 0.5% xanthan gum (XG) / carrageenan (Car) and different concentrations of sodium carboxymethyl cellulose (CMC) (0%, 0.5%, 1%) were added in deionized water and stirred until fully mixed. After the mixture containing pea protein isolate was mixed with it and continued to stir for 30 minutes, it was mixed with 8% edible oil and homogenized at 100,00r / min for 5 minutes using a high-speed homogenizer to obtain a paste mixture. Finally, it was bathed in water at 85°C for 30 minutes and cooled on ice for 30 minutes to obtain an emulsion ink. The samples were named XG-0%, CP-XG-0%, CP-XG-0.5%, CP-XG-1%, Car-0%, CP-Car-0%, CP-Car-0.5%, and CP-Car-1%, among which XG-0% and Car-0% were the control groups.

[0032] Example 2 Performance test: The rheological properties of the ink were determined using a DHR-2 rheometer: different emulsion ink samples were placed between the instrument and a 40 mm parallel plate geometry with a slit gap width of 1000 μm. Liquid paraffin was applied to the periphery of the sample in the gap to prevent water migration. Before the test, the ink was balanced at 25 ° C for 120 seconds to reach a stable state. At a shear rate of 0.1 s -1 Up to 100s -1 The apparent viscosity of the ink was measured under the conditions of . The frequency was scanned in the range of 0.1-10 rad / s. All measurements were repeated three times at 25°C. The experimental results are shown in Figure 1 and Figure 2 As shown, Figure 1 The left figure shows the apparent viscosity test results of each group of inks when the affinity colloid is XG. Figure 1 The right figure in the figure shows the apparent viscosity test results of each group of inks when the affinity colloid is Car; Figure 2 The middle left picture shows the frequency scanning results of each group of inks when the affinity colloid is XG. Figure 2 The middle right figure shows the frequency scanning results of each group of inks when the affinity colloid is Car.

[0033] The relationship between apparent viscosity and shear rate was calculated and fitted using a power law model: η=K×γ n-1 Where η is the apparent viscosity (Pa⋅s), ̇γ is the shear rate (1 / s), and K is the consistency coefficient (Pa⋅s n ), n is the flow behavior index. The fitting results are shown in Table 1.

[0034] Table 1 Depend on Figure 1 , Figure 2 As shown in Table 1, for the same type of ink, the PPI ink treated with CP has a lower shear rate (0.1s -1 -10s -1 ) showed a higher apparent viscosity and reached the maximum when the CMC addition was 0.5%. Comparing the two different edible gums, the ink composed of xanthan gum has a higher apparent viscosity, indicating that the presence of xanthan gum is more conducive to the formation of a hydrocolloid network structure. The inks of Car-0.5% and XG-0.5% treated with CP have the highest K value, reaching 340.90±24.71 Pa·s n and 368.57±22.38 Pa·s n . According to the frequency scanning results, the G' value of the PPI emulsion ink treated with CP is significantly higher than that of the untreated emulsion ink, indicating that the mechanical properties of the ink treated with CP are stronger. With the increase of CMC addition, G' and G'' increase at the same time, indicating that the addition of CMC polysaccharide molecules is conducive to the formation of a denser gel structure and improves the mechanical properties of the emulsion gel. After CP treatment, the hardness, adhesiveness, gumminess and cohesiveness of the emulsion gel have a significant effect and show an upward trend. The reason for this phenomenon is that after appropriate CP treatment, under the action of active particles such as ozone and hydroxyl radicals, hydrophobic interactions and the formation of disulfide bonds are promoted, thereby improving the mechanical properties of the gel and forming a more ordered and highly cross-linked 3D gel network. Compared with the ink without CMC, the hardness of the plant meat increased significantly after adding CMC (0.5%~1%) (P<0.05). Among them, the hardness values ​​of the ink containing 0.5% CMC reached the highest values ​​(309.6g and 309g), because the addition of appropriate polysaccharide concentrations enhanced the intermolecular protein interaction and promoted protein aggregation, thereby accelerating the formation of gel network and improving gel strength. It is also attributed to the hydrogen bonds formed between proteins and polysaccharides, making the gel structure more complete.

[0035] 3D printing experiment: FoodBot-S2PRO printer is used for 3D printing of plant meat. According to the previous experiments, the 3D printing parameters were optimized, and the printing speed was set to 10mm / s, the nozzle diameter was 0.8mm, and the filling density was 20%. Use Tinkercad to design a 3D hollow cuboid model with a height of 20mm and a diameter of 30mm. Then, the created 3D hollow cube model is loaded into the Cura software to generate the G code, which is imported into the 3D printer via USB to facilitate the 3D printing of the model. The syringe barrel filled with emulsion ink of different ratios is loaded into the temperature-controlled cartridge bottle and printed after keeping it at 25°C for 15 minutes. The printed plant meat photo is shown below. Figure 3 shown.

[0036] Water fluidity analysis: The water mobility experiment of emulsion ink was carried out using a low-frequency nuclear magnetic resonance analyzer. The relaxation time T2 is used to characterize the distribution of water molecules in the gel and the information on water migration. Weigh 3g of ink, wrap it with plastic wrap before measurement and put it into the measuring glass tube, and test it in the Carr-Purcell-Meiboom-Gill (CPMG) pulse sequence mode. The parameters are set as follows: sampling frequency 200kHz, number of sampling points 200010, number of echoes 5000, echo time 0.2ms, waiting time 3000ms, use built-in software for data inversion, convert signal attenuation into relaxation time, the number of scans is selected as 30,000 times, and the low-frequency nuclear magnetic resonance results are as follows. Figure 4 As shown, Figure 4 The middle left picture shows the low-frequency NMR results of each group of inks when the affinity colloid is XG. Figure 4 The middle right picture shows the low-frequency NMR results of each group of inks when the affinity colloid is Car. According to the water distribution, the water group of fixed water accounts for the largest proportion and has a dominant influence on the rheological properties of the emulsion ink. After CP treatment, the relaxation time of water in the emulsion ink is reduced. This may be because the PPI emulsion ink treated with CP has a stronger binding force on water molecules, forming a denser gel network structure, resulting in a phase shift of the proton loudsound after the frequency pulse is turned off, thereby shortening the relaxation time. As the CMC content increases from 0% to 0.5%, the fixed water relaxation time gradually decreases, and the relaxation time of xanthan gum and carrageenan inks decreases from 54.79ms to 51.11ms, and 54.92ms to 52.34ms, respectively, indicating that the addition of CMC will reduce the fluidity of water, which may be due to the formation of hydrogen bonds between water molecules and polymers, which hinders the migration of water, forms a tighter gel network structure, and enhances the gel strength.

[0037] X-ray diffraction test: Place the ink in a freeze dryer, freeze dry for 48 hours, take it out, grind it, sieve it, and store it in a -20℃ refrigerator for testing. The X-ray diffraction patterns of all samples under Cu radiation (λ=1.5418Å) are recorded by an X-ray powder diffractometer. The working voltage is 40kV, the working current is 40mA, and the sample diffraction pattern of X-rays under 2θ is recorded at a scanning speed of 0.02° / min, ranging from 5° to 50°. The d value is determined by the Bragg equation:

[0038] Where: 𝑛 is the diffraction order (usually 1); 𝜆 is the wavelength of the X-ray; d is the interplanar spacing. 𝜃 is the diffraction angle. The X-ray diffraction results are as follows Figure 5 As shown, Figure 5 The middle left picture shows the X-ray diffraction results of each group of inks when the affinity colloid is XG. Figure 5 The middle right figure shows the X-ray diffraction results of each group of inks when the affinity colloid is Car. According to the results of the X-ray diffractometer, all inks show two peaks at diffraction angles of about 9° and 19° at 2θ, corresponding to d spacings of 9.8Å and 4.5Å. This indicates that its crystal structure is mainly composed of α-helix and β-helix structures. The PPI ink treated with CP produced a relatively flat peak near 9°, indicating that the α-helix structure is reduced and may be transformed into β-folding, indicating that CP treatment has a more stable latex gel ink structure. Compared with the untreated group, the diffraction peak intensity of the latex gel gradually decreases and the diffraction peak angle moves to a lower direction. When the CMC addition amount is 0.5%, the diffraction peaks of the latex gel are 18.71° and 19.15°, respectively. This may be due to the good compatibility between protein and polysaccharide, the decrease in the crystallinity of the latex gel, the destruction of the regular rigid structure of the protein molecule, and the increase in overall flexibility, resulting in a smaller crystal size.

[0039] Molecular interaction force detection: The solutions were prepared as follows: A: deionized water, B: buffer (pH 8.0) containing Tris (0.086 mol / L), glycine (0.09 mol / L) and disodium ethylenediaminetetraacetate (4 mmol / L); C: 20 g / L sodium dodecyl sulfate was added to a certain volume of solution B; D: urea was added to a certain volume of solution C to reach 8 mol / L; E: a certain volume of solution D was taken and 1% (v / v) β-mercaptoethanol was added. Weigh 500 mg of the emulsion gel and add 9.5 mL of the above five solutions respectively. After homogenization at 100,00 rpm for 2 min, the solution was placed in a water bath at 25 ° C for 20 min. Centrifuge at 8000 rpm for 10 min at 4 ° C, determine the content by the biuret method, and calculate the protein solubility of the sample as follows:

[0040] BA represents electrostatic interaction, CB represents hydrophobic interaction, DC represents hydrogen bonding, and ED represents disulfide bonding. Figure 6 As shown, Figure 6 The middle left picture shows the molecular force test results of each group of inks when the affinity colloid is XG. Figure 6 The middle right picture shows the molecular interaction force test results of each group of inks when the affinity colloid is Car. Figure 6 It can be seen that hydrogen bonding is the main molecular force between PPI and polysaccharides such as xanthan gum in the latex gel, which indirectly affects the gel properties by affecting the stability of the protein conformation, indicating that hydrogen bonding-based non-covalent unstable gel structures and aggregates are formed. With the increase of CMC content, the surface functional groups such as carboxyl and amino groups in PPI treated with CP are exposed, and hydrogen bonding interactions are formed with a large number of hydroxyl groups in CMC. The addition of polysaccharides greatly enhances the interaction between protein and polysaccharide, forming a more stable and homogeneous latex gel. From the molecular interaction force results of carrageenan, it can be seen that in the unmodified pea protein latex gel, hydrophobic interactions are dominant. With the increase of polysaccharide concentration, hydrophobic interactions are gradually replaced by hydrogen bonds and disulfide bonds, which may be due to the formation of hydrogen bonds and steric hindrance effects between CMC and the carboxyl and amino groups of proteins, and the change of the hydrophobicity of some side chains. The content of disulfide bonds increases significantly with the increase of CMC content (0% - 0.5%), promoting the cross-linking between protein molecules and polysaccharides and enhancing the mechanical strength of the sample.

[0041] Mechanical properties test: A physical property analyzer equipped with P50 was used to measure the texture characteristics of 3D printed plant meat. The test parameters were set as follows: Pre-Test Speed: 1.5 mm / sec, Test Speed: 1.00 mm / sec, Post-Test Speed: 1.0 mm / sec, Strain: 50%, Time: 5.00 sec, Trigger Type: 5.0 g. The measurement was carried out at 25 ° C, and each sample was tested three times for repeatability. The test results are shown in the figure below. Figure 7 shown.

[0042] Plant meat 3D printing technology is based on the application and development of traditional 3D printing technology in the food field. Due to its high precision and wide material versatility, it has been widely used in the food industry and has better development prospects. Cold plasma is a non-thermal treatment technology. The specific embodiment of the present invention uses argon as a carrier gas to modify pea protein isolate, and at the same time proves its progressiveness. The 3D printing ink provided by the specific embodiment of the present invention has broad application prospects in the production and processing of plant meat.

[0043] Although the disclosure is disclosed as above, the protection scope of the disclosure is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the disclosure, and these changes and modifications will fall within the protection scope of the present invention.

Claims

1. A 3D printing ink based on pea protein isolate, characterized in that: The invention comprises the following raw materials in parts by weight: 10-20% of modified pea protein isolate modified by cold argon plasma, 0.2-1% of affinity colloid, 0.5-1% of sodium carboxymethyl cellulose, 5-10% of edible oil, and the balance is a sodium chloride aqueous solution with a sodium chloride concentration of 0.5-1%, wherein the affinity colloid is xanthan gum or carrageenan.

2. A method for preparing a 3D printing ink based on pea protein isolate according to claim 1, characterized in that: The following steps are involved: S1: modifying pea protein isolate by cold argon plasma to obtain modified pea protein isolate; S2: mixing the sodium chloride aqueous solution and the modified pea protein isolate to obtain a hydrated modified pea protein isolate; S3: adding affinity colloid and sodium carboxymethyl cellulose to the hydrated modified pea protein isolate solution, stirring evenly, adding edible oil, and high-pressure homogenization to obtain a gelatinized product; S4: The gelatinized material is heated and then cooled to 0-4°C to obtain 3D printing ink.

3. The preparation method according to claim 2, characterized in that: The step S1 comprises the following steps: S11: treating a 10-20% (w / w) pea protein isolate solution with a cold argon plasma jet; S12: After the cold argon plasma treatment is completed, the pea protein isolate solution is placed at 0-8° C. for cooling for 16-18 hours to obtain a modified pea protein isolate.

4. The preparation method according to claim 3, characterized in that: In step S11, the parameters of the cold argon plasma jet treatment are: the height between the liquid surface and the nozzle is 8-12 mm, the standard flow rate is 2-5 L / min, and the power is 70-80 W.

5. The preparation method according to claim 3, characterized in that: In step S11, the duration of the cold argon plasma jet treatment is 4 to 10 minutes.

6. The preparation method according to claim 2, characterized in that: In step S2, the hydration temperature is 2-8°C.

7. The preparation method according to claim 2, characterized in that: In step S3, the parameters of high pressure homogenization are: rotation speed 7000-12000 r / min, and homogenization time 3-7 min.

8. The preparation method according to claim 2, characterized in that: In step S4, the heating parameters are: heating temperature is 80-90° C., and heating time is 20-40 min.

9. An application of the pea protein isolate-based 3D printing ink according to claim 1, characterized in that: The pea protein isolate-based 3D printing ink is used for the preparation of artificial meat.

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