Preparation method and application of proteolytic aggregate-citrus pectin-based high internal phase emulsion suitable for 3D printing

Abstract

The invention belongs to the technical field of food processing, and particularly relates to a preparation method and application of a proteolytic aggregate-citrus pectin-based high internal phase emulsion suitable for 3D printing. A compound of citrus pectin and soybean protein enzymatic aggregate is used as a stabilizer and an emulsifier, edible oil is used as an oil phase, the protease enzymatic aggregate-citrus pectin based high internal phase emulsion is obtained through homogenization treatment, and the high internal phase emulsion has high extrudability, self-supporting performance and stability, can be used for different 3D printing models, and has good application prospects. And the preparation operation cost is low, the preparation method is simple and easy, industrial application is easy, and a new strategy is provided for sustainable high-value application of low-value protein enzymolysis byproducts in novel functional peptidyl emulsion food / food ingredients.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of food processing, and more particularly relates to a preparation method of a proteinase-promoted aggregate-citrus pectin-based high internal phase emulsion suitable for 3D printing and application thereof. BACKGROUND

[0002] Food 3D printing technology can set food according to the body condition, nutritional needs and personal preferences of the target population, and is called the frontier technology of future food manufacturing. High internal phase emulsion refers to a kind of emulsion with a dispersed phase volume of more than 74.05%, which has good self-supporting ability and shear-thinning rheological properties, and has great potential in the aspect of being used as 3D printing materials.

[0003] The selection and optimization of high internal phase emulsion stabilizers are key factors to ensure the stability of high internal phase emulsion systems, which directly affect the forming effect and final performance of 3D printing materials. Particles based on natural proteins have become promising stabilizers for preparing high internal phase emulsions due to their unique properties such as edibility, safety, good interfacial adsorption capacity and emulsifying performance. Compared with animal proteins, plant proteins have the advantages of green, vegetarian and economy, and are concerned in the application of high internal phase emulsions, but most plant protein particles have low wettability and limited ability to stabilize oil-water interface, which hinders their application in 3D printing of high internal phase emulsions.

[0004] The high internal phase emulsion combined with protein and polysaccharide is used as 3D food printing ink, and the polysaccharide can be cross-linked with the protein after the unfolding of the protein molecular structure, and the increase of the viscosity of the system can promote the adsorption of the protein on the oil-water interface to form a complex network, thereby improving the performance of the high internal phase emulsion as 3D printing ink. At present, the protein polysaccharide-based materials available for 3D printing are very limited, and the interface instability in the process of 3D printing of high internal phase emulsion based on protein polysaccharide cooperation limits the selection of 3D printing food materials and product development. Therefore, the development of food-grade materials with excellent printing performance has become a difficult problem to be solved in the current field of food science. SUMMARY

[0005] The purpose of the present application is to provide a preparation method of a proteinase-promoted aggregate-citrus pectin-based high internal phase emulsion suitable for 3D printing and application thereof, so as to solve the problems existing in the prior art.

[0006] To achieve the above-mentioned purpose, the present application provides the following solutions: One of the technical solutions of the present application provides a preparation method of a proteinase-promoted aggregate-citrus pectin-based high internal phase emulsion suitable for 3D printing, which comprises the following steps: mixing the soybean proteinase aggregate with water, dispersing uniformly, adjusting pH to 10.0-12.0, stirring for 0.5-1 h, and then adjusting pH to 7.0 to obtain a soybean proteinase aggregate dispersion; adding citrus pectin to the soybean proteinase aggregate dispersion, and after mixing and processing, obtaining a soybean proteinase aggregate-citrus pectin stabilizer; mixing the soybean proteinase aggregate-citrus pectin stabilizer with an oil phase, and after homogenization processing, obtaining the proteinase aggregate-citrus pectin-based high internal phase emulsion.

[0007] Further, the preparation steps of the soybean proteinase aggregate include: dissolving soybean protein isolate in water, after enzymatic treatment, adjusting pH to 7.0, boiling water bath to inactivate the enzyme, centrifugation, collecting the insoluble precipitate component, water washing, and drying to obtain the soybean proteinase aggregate.

[0008] Optionally, the pH value of the enzymatic treatment is 6.0-9.0, the temperature is 40-60℃, and the time is 6-24 h.

[0009] Optionally, the enzyme used in the enzymatic treatment includes alkaline protease or Novozymes complex protease Protamex, and the enzyme addition amount is 0.1-1.0% of the mass of the soybean protein isolate.

[0010] Optionally, the drying is freeze-drying.

[0011] Further, the concentration of the soybean proteinase aggregate dispersion is 2-4 wt%.

[0012] Further, the mass ratio of the soybean proteinase aggregate dispersion and citrus pectin is 3:0.5-3.

[0013] Further, the mixing and processing steps include: After mixing the citrus pectin with the soybean proteinase aggregate dispersion, under magnetic stirring at 1000 rpm, adjusting pH to 7.0 and maintaining pH balance for 1 h, the soybean proteinase aggregate-citrus pectin stabilizer is obtained.

[0014] Further, the volume ratio of the soybean proteinase aggregate-citrus pectin stabilizer and the oil phase is 1:3.

[0015] Further, the oil phase is vegetable oil.

[0016] Optionally, the vegetable oil is corn oil containing 0.5 wt% sweet orange essential oil.

[0017] Further, the rotation speed of the homogenization treatment is 6000-10000 rpm, and the time is 60-120 s, preferably, the rotation speed is 8000 rpm, and the time is 90 s.

[0018] The second technical scheme of the present application provides a proteinase-induced aggregate-citrus pectin-based high internal phase emulsion suitable for 3D printing, which is prepared by the above preparation method.

[0019] The third technical scheme of the present application provides an application of the above proteinase-induced aggregate-citrus pectin-based high internal phase emulsion suitable for 3D printing in food 3D printing.

[0020] The fourth technical scheme of the present application provides a 3D printed food, and the raw materials include the above proteinase-induced aggregate-citrus pectin-based high internal phase emulsion.

[0021] The fifth technical scheme of the present application provides a preparation method of the above 3D printed food, which uses the proteinase-induced aggregate-citrus pectin-based high internal phase emulsion as a 3D printing ink and is prepared by 3D printing.

[0022] Further, the parameters of the 3D printing include: nozzle diameter 1.0 mm, travel speed 30 mm / s, retraction speed 50 mm / s, filling speed 40 mm / s, and filling density 80%.

[0023] The present application discloses the following technical effects: The present application uses citrus pectin to further improve the emulsification efficiency of soybean proteinase-induced aggregates under neutral conditions, so that the high internal phase emulsion formed has high self-supporting property, good storage stability and thermal stability. The 3D printing of the high internal phase emulsion proves that it has good extrusion property and printing performance, especially when the soybean proteinase-induced aggregate-citrus pectin composite ratio is 3:3, the printing precision is significantly improved, and the 3D printed sample can maintain stable 3D printed structure after being stored in a 4℃ refrigerator for 7 days, which is beneficial to prolong the storage period of 3D printed food and broaden the selection range of food-grade ink materials for 3D printing.

[0024] The proteinase-induced aggregate-citrus pectin-based high internal phase emulsion prepared by the present application can be used as a 3D printing ink to develop texture-modified food for dysphagia patients, so as to broaden its personalized customization application in 3D printing, and thus create future food with the advantages of fusion flavor, nutrition and environmental sustainability.

[0025] The present application has low operation cost, short production cycle, simple preparation method, can be prepared on a large scale, and is easy to be applied in industry, thereby providing a new strategy for sustainable high-value application of low-value protein enzymatic by-products in novel functional peptide-based emulsion food / food ingredients. Attached Figure Description

[0026] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 The images show the appearance of the high internal phase emulsions prepared in Examples 1-4 and Comparative Example 1, where A is the visual appearance and B is the planar appearance.

[0027] Figure 2 The droplet volume distribution, particle size, and Zeta potential of the high internal phase emulsions prepared in Examples 1-4 and Comparative Example 1 are shown, where A represents the droplet volume distribution and B represents the particle size. d 4,3 The value, C, is the Zeta-potential.

[0028] Figure 3 Microscopic images of the high internal phase emulsions prepared in Examples 1-4 and Comparative Example 1.

[0029] Figure 4 The droplet interface microstructures of the high internal phase emulsions prepared in Examples 1-4 and Comparative Example 1 are shown. In the figures, A represents the overall fluorescence signal of the high internal phase emulsion, B represents the fluorescence signal of citrus pectin, C represents the fluorescence signal of the oil phase, and D represents the fluorescence signal of the protein.

[0030] Figure 5 The rheological properties of the high internal phase emulsions prepared in Examples 1-4 and Comparative Example 1 are shown, where A represents steady-state rheological behavior and B represents dynamic rheological behavior.

[0031] Figure 6 The images show the appearance of 3D printed samples using the high internal phase emulsions prepared in Examples 1-4 and Comparative Example 1 as printing inks. In the images, A is the appearance of the 3D printed sample, B is the appearance of the 3D printed cylinder for stability observation, and C is the appearance of the 3D printed cylinder for printing accuracy stability.

[0032] Figure 7 The 3D printing stability of the high internal phase emulsions prepared in Examples 1-4 and Comparative Example 1 as printing inks is shown in the figure. A represents the 3D printing sample length stability, B represents the edge height stability, C represents the center height stability, and D represents the printing accuracy and printing stability.

[0033] Figure 8 The textural distributions of the 3D printed samples of Examples 1-4 and Comparative Example 1 are shown, where A represents hardness, B represents adhesion, C represents elasticity, D represents cohesion, E represents viscousity, and F represents resilience.

[0034] Figure 9International Dysphagia Diet Standardized Test results for the 3D printed samples of Examples 1-4 and Comparative Example 1. DETAILED DESCRIPTION

[0035] Various exemplary embodiments of the present application will now be described in detail, with reference to the figures. The detailed description is merely intended to teach a person of ordinary skill in the art how to make and use the present application and is not intended to limit the scope of the application. Therefore, the description of the exemplary embodiments is not intended to limit the scope of the application.

[0036] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the present application. In addition, where particular ranges of values are given, understand that each intervening value, to the upper or lower limit of the ranges is also specifically included. Each smaller range that falls within the broader ranges is also specifically included. The upper and lower limits of these smaller ranges can independently be included or excluded in the range, and each range is inclusive of its end points.

[0037] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. Although preferred methods and materials are described, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present application. All documents mentioned herein are incorporated by reference to disclose and describe the methods and / or materials in connection with which the documents are cited. In case of conflict, the present specification will control.

[0038] Various modifications and changes can be made to the specific embodiments of the present application described herein without departing from the scope or spirit of the application. Other embodiments of the application will be apparent to those of ordinary skill in the art from the description and examples presented herein. The description and examples are illustrative of the application and are not intended to limit the scope of the application.

[0039] As used herein, the terms "comprise", "comprising", "include", "including", "have", "having" or the like are open-ended and do not exclude additional, unrecited elements or method steps.

[0040] Unless otherwise specified, all raw materials and reagents involved in the embodiments of the present application are commercially available.

[0041] Unless otherwise specified, room temperature and normal temperature in the embodiments of the present application both refer to 20-30°C.

[0042] It should be noted that the present application does not describe the details of the conventional operation means in the art, and is not the focus of the present application.

[0043] In some specific embodiments, the present application provides a preparation method of a proteinase-induced aggregate-citrus pectin-based high internal phase emulsion suitable for 3D printing, the steps comprising: S1, dissolving soybean protein isolate in water, adding alkaline protease or Novozymes complex protease Protamex for enzymolysis, the enzymolysis conditions are: pH value 6.0-9.0, enzyme addition amount is 0.1-1.0% of the mass of soybean protein isolate, reaction temperature is 40-60℃, reaction time is 6-24h; after the enzymolysis reaction is completed, the pH value of the protease hydrolysate is adjusted to 7.0, the enzyme is inactivated in a boiling water bath, centrifuged, the insoluble precipitate component is collected, washed with water, and freeze-dried to obtain soybean proteinase-induced aggregates S2, mixing the soybean proteinase-induced aggregates obtained in step S1 with deionized water, stirring at 550rpm at room temperature for 2h, adjusting the pH to 10.0-12.0 with NaOH solution, stirring magnetically for 0.5-1h, then adjusting the pH to 7.0 with HCl solution, transferring to a 4℃ refrigerator and standing overnight for hydration, to obtain a soybean proteinase-induced aggregate dispersion liquid with a concentration of 2-4wt%; S3, adding citrus pectin to the soybean proteinase-induced aggregate dispersion liquid obtained in step S2, mixing under magnetic stirring at 1000rpm, adjusting the pH to 7.0 and maintaining pH balance for 1h to obtain a soybean proteinase-induced aggregate-citrus pectin stabilizer; Wherein, the pH is adjusted using 2mol / L sodium hydroxide solution and 2mol / L hydrochloric acid solution; the mass ratio of the soybean proteinase-induced aggregate dispersion liquid and the citrus pectin is 3:0.5-3; S4, mixing the soybean proteinase-induced aggregate-citrus pectin stabilizer obtained in step S3 with an oil phase at a volume ratio of 1:3, and homogenizing at a speed of 6000-10000rpm for 60-120s to obtain a soybean proteinase-induced aggregate-citrus pectin-based high internal phase emulsion; Wherein, the oil phase is vegetable oil, specifically corn oil containing 0.5wt% sweet orange essential oil.

[0044] In step S2, the pH is adjusted to 10.0-12.0 and then adjusted back to 7.0, which reduces the particle size of the proteinase-induced aggregate, and nanometer-micro-sized colloidal particles are prepared, improving the solubility and dispersibility of the aggregate.

[0045] Example 1 The preparation steps of the proteinase-induced aggregate-citrus pectin-based high internal phase emulsion suitable for 3D printing include: S1, soybean protein isolate was dissolved in water, and alkaline protease or Novozymes complex protease Protamex was added for enzymolysis, and the enzymolysis conditions were as follows: pH value was 8.0, enzyme addition amount was 1.0% of the mass of soybean protein isolate, reaction temperature was 50℃, and reaction time was 12h; after the enzymolysis reaction was completed, the pH value of the protease hydrolysate was adjusted to 7.0, centrifugation was performed, the insoluble precipitate component was collected, water washing was performed, and freeze-drying was performed to obtain soybean proteinase aggregation S2, the soybean proteinase aggregation obtained in step S1 was mixed with deionized water, and after magnetic stirring at 550rpm for 2h at room temperature, NaOH solution was used to adjust the pH to 10.0, magnetic stirring was performed for 1h, then HCl solution was used to adjust the pH to 7.0, and the mixture was transferred to a 4℃ refrigerator and statically hydrated overnight to obtain a soybean proteinase aggregation dispersion liquid with a concentration of 4wt%; S3, citrus pectin was added to the soybean proteinase aggregation dispersion liquid obtained in step S2, and after mixing under magnetic stirring at 1000rpm, the pH was adjusted to 7.0 and maintained for 1h to obtain a soybean proteinase aggregation-citrus pectin stabilizer; wherein the pH was adjusted using 2mol / L sodium hydroxide solution and 2mol / L hydrochloric acid solution; the mass ratio of the soybean proteinase aggregation dispersion liquid to the citrus pectin was 3:0.5; S4, the soybean proteinase aggregation-citrus pectin stabilizer obtained in step S3 was mixed with an oil phase at a volume ratio of 1:3, and high-speed homogenization was performed at a speed of 8000rpm for 90s to obtain a proteinase aggregation-citrus pectin-based high internal phase emulsion; wherein the oil phase was corn oil containing 0.5wt% sweet orange essential oil.

[0046] Example 2 Compared with example 1, the only difference is that in step S3, the mass ratio of the soybean proteinase aggregation dispersion liquid to the citrus pectin is 3:1.

[0047] Example 3 Compared with example 1, the only difference is that in step S3, the mass ratio of the soybean proteinase aggregation dispersion liquid to the citrus pectin is 3:2.

[0048] Example 4 Compared with example 1, the only difference is that in step S3, the mass ratio of the soybean proteinase aggregation dispersion liquid to the citrus pectin is 3:3.

[0049] Comparative example 1 Compared with example 1, the only difference is that in step S3, the mass ratio of the soybean proteinase aggregation dispersion liquid to the citrus pectin is 3:0.

[0050] Test example The high internal phase emulsions prepared in Examples 1-4 and Comparative Example 1 were photographed after standing for 24 hours to observe their visual appearance and planar appearance.

[0051] Figure 1 The images show the appearance of the high internal phase emulsions prepared in Examples 1-4 and Comparative Example 1, where A is the visual appearance and B is the planar appearance.

[0052] Using deionized water as a dispersant, the particle size distribution of the high internal phase emulsions prepared in Examples 1-4 and Comparative Example 1 was determined using a Mastersizer 2000. Each sample was diluted 1000-fold with deionized water before measurement. Subsequently, the zeta potential of the high internal phase emulsions was determined using a Nano ZS. The pH electrode was used to monitor the dilution process in real time to ensure that the pH of the sample did not change significantly during the dilution process.

[0053] Figure 2 The droplet volume distribution, particle size, and Zeta potential of the high internal phase emulsions prepared in Examples 1-4 and Comparative Example 1 are shown, where A represents the droplet volume distribution and B represents the particle size. d 4,3 The value, C, is the Zeta-potential.

[0054] Depend on Figures 1-2 It can be seen that as the proportion of citrus pectin increases, the planar appearance of the high internal phase emulsion becomes clearer, the particle size decreases, and the absolute value of the Zeta-potential increases, indicating that the addition of citrus pectin can give the emulsion better emulsification properties.

[0055] The microstructure of high internal phase emulsions (HIPEs) was observed using optical microscopy and laser confocal microscopy. First, a portion of the HIPE was evenly placed on a glass slide and covered. The microscopic image of the HIPE was then observed under a 10x objective lens using an optical microscope. Next, 1 mL of HIPEs was mixed with 20 μL of Nile Red (0.1%, w / v) and 20 μL of Nile Blue (0.1%, w / v) and allowed to stand for 30 minutes. A small droplet of the stained HIPE was then placed on a concave confocal microscope slide and covered. The droplet interface microstructure of the HIPEs was observed under a 40x objective lens using an argon / krypton laser (488 nm for Nile Red) and a helium-neon laser (HeNe) with excitation wavelengths of 635 nm for Nile Blue.

[0056] Figure 3 The images show microscopic images of the high internal phase emulsions prepared in Examples 1-4 and Comparative Example 1. The scale bar in the images is 100 µm. As can be seen from the images, the high internal phase emulsions with a higher citrus pectin concentration exhibit a more compact and uniform droplet distribution system.

[0057] Figure 4The droplet interface microstructure of the high internal phase emulsions prepared in Example 1-4 and Comparative Example 1 was prepared, wherein A is the fluorescence signal of the whole high internal phase emulsion, B is the fluorescence signal of the citrus pectin, C is the fluorescence signal of the oil phase, and D is the fluorescence signal of the protein. In the figure, the scale is 25 pm, and it can be seen from the figure that the protein presents red fluorescence, the oil phase presents green fluorescence, and the pectin presents blue fluorescence. With the increase of the ratio of citrus pectin, the intensity of the blue fluorescence region is stronger, and the increase of the concentration of citrus pectin effectively inhibits the movement of oil droplets and prevents further fusion.

[0058] The rheological behavior of the high internal phase emulsion was characterized using a HAAKE MARS III rheometer. A coin-sized amount was scraped onto the bottom plate of the rheometer, and then the apparent viscosity of the sample was measured using the rheometer at a shear rate of 0.1-100 s -1 -1, and the temperature was maintained at 25°C. In addition, the storage modulus (G') G' ) and loss modulus (G" G'' ) of the emulsion were determined at different strain levels (from 0.01%-100%), and the frequency range was set to 0.1-10 Hz.

[0059] Figure 5 The rheological properties of the high internal phase emulsions prepared in Example 1-4 and Comparative Example 1 were as follows: A was the steady-state rheological behavior, and B was the dynamic rheological behavior. As can be seen from the figure, the viscosity of all the high internal phase emulsions gradually decreased in the shear rate range, which was a typical shear thinning behavior. For all the high internal phase emulsions from 0.1 to 10 Hz, G' > 1, G'' , indicating that all the high internal phase emulsions exhibited gel-like behavior. With the increase of the ratio of citrus pectin, the viscosity of the high internal phase emulsion gradually increased, G' , indicating that the increasing concentration effect of citrus pectin had the effect of enhancing the gel network structure, thereby making the high internal phase emulsion have a rigid structure resistant to deformation.

[0060] The 3D printer used below is model MX-S, brand Nanjing Xianou Microwave Food 3D Printer.

[0061] The high internal phase emulsions prepared in Example 1-4 and Comparative Example 1 were used as printing ink, and 3D printing was carried out according to the following parameters: Nozzle diameter 1.0 mm, travel speed 30 mm / s, retraction speed 50 mm / s, filling speed 40 mm / s, and filling density 80%.

[0062] The high internal phase emulsion sample was loaded into a 30 mL syringe, and different 3D printing models (cylinder, cube, and watermelon popsicle) were designed using Tinkercad software to enrich the diversity and customization of 3D printing patterns, and then sliced into G-code files compatible with the extrusion 3D printer using Cura software. After 3D printing, the sample was photographed, and the edge height, center height, and bottom length of the sample were measured using a vernier caliper to evaluate the printing accuracy of the 3D printed sample. Second, the prepared 3D printed sample was stored at 4°C for 7 days, then photographed and the printing accuracy was investigated to evaluate the stability of 3D printing. The formula is as follows: ; In the formula, H e , H c , and L b represent the edge height, center height, and bottom length of the 3D printed sample, mm; H s and L s are the set height and set bottom length of the 3D printing model, mm.

[0063] Figure 6 The appearance of the 3D printed sample prepared from the high internal phase emulsion of Examples 1-4 and Comparative Example 1 as printing ink, wherein A is the appearance of the 3D printed sample, B is the stability observation appearance of the 3D printed cylinder, and C is the appearance of the stability of the printing accuracy of the 3D printed cylinder. As can be seen from the figure, the sample appearance without added citrus pectin shows a collapsed phenomenon, and the sample shows oil migration and relatively rough texture. With the increase of the concentration of citrus pectin, the sample printed by the high internal phase emulsion of soybean proteinase-polymerized aggregate-citrus pectin at a ratio of 3:3 has the best effect, and the shape of the printed object is consistent with the designed geometry. The appearance of the cube sample, the watermelon popsicle sample, and the cylinder sample changes consistently.

[0064] Figure 7The high internal phase emulsions prepared for Examples 1-4 and Comparative Example 1 were evaluated for 3D printing stability as printing inks, where A is 3D printed sample length stability, B is edge height stability, C is center height stability, and D is printing accuracy and printing stability. As can be seen from the figure, for the length, edge height, and center height of the printing cylinder, the measured length of all 3D printed cylinders exceeded the center height value of the model, and only the sample with a ratio of soy protein enzymatic aggregate-citrus pectin of 3:3 met the set value of the model for the edge height and the center height. The sample with a ratio of soy protein enzymatic aggregate-citrus pectin of 3:3 had the highest printing accuracy of 99.05%, followed by the sample with a ratio of soy protein enzymatic aggregate-citrus pectin of 3:2, which had a printing accuracy of 92.16%, and the printing accuracy of the remaining samples with lower concentrations of citrus pectin decreased in turn, which indicated that the samples with high concentrations of citrus pectin had good self-supporting properties after printing due to their strong mechanical properties, and the printed samples had high resolution, internal line adhesion, and shape accuracy. This can be attributed to the 3D printing ink (i.e., the high internal phase emulsion) of the sample with a high concentration of citrus pectin, which had a small particle size, a tight interface structure, and improved rheological properties due to the introduction of citrus pectin, thereby making the high internal phase emulsion have excellent printing suitability. In addition, the 3D printed sample also needs to have a bearing capacity to maintain the firmness of the printed shape. Further evaluation of the printing accuracy of the 3D printed samples stored for 7 days showed that the samples with a ratio of soy protein enzymatic aggregate-citrus pectin of 3:3 and 3:2 still had a stable appearance, and the printing accuracy was 96.44% and 88.11%, respectively. In general, the addition of high concentrations of high internal phase emulsions can effectively improve the printing accuracy of the HIPEs 3D printed samples.

[0065] The 3D printed samples were stored at room temperature for 2 h to stabilize the structure, and then the texture profile was measured using a TA-XTplus texture analyzer with a P36 R probe. The texture profile mode was performed by 2 cycles, with a strain of 35%, a test speed of 1.0 mm / s, and a trigger force of 5 g.

[0066] Figure 8 The texture profile of the 3D printed samples of Examples 1-4 and Comparative Example 1 is shown in the figure, where A is hardness, B is adhesiveness, C is elasticity, D is cohesiveness, E is viscosity, and F is resilience. As can be seen from the figure, the 3D printed sample made of the high internal phase emulsion with a ratio of soy protein enzymatic aggregate-citrus pectin of 3:3 not only had the highest hardness, cohesiveness, and viscosity, but also had the lowest adhesiveness. The introduction of the high internal phase emulsion with citrus pectin and the combination of 3D printing technology can improve the ease of swallowing, and different 3D printed products with different swallowing grades are obtained. As the content of citrus pectin increases, the swallowing performance grade increases Figure 9The fork drip test can reflect that the 3D printed samples with high concentration of citrus pectin incorporated into the high internal phase emulsion have the potential to be the ideal diet for the dysphagia population.

[0067] The spoon tilt test, fork drip test and fork pressure test were performed on the 3D printed samples using a spoon and a fork respectively, and the results were compared with the International Dysphagia Diet Standardization Initiative standard description to determine the grade of each sample and evaluate its swallowing performance. The tests were performed according to the following steps: first, the spoon tilt test was performed by scooping a spoonful of sample and holding the spoon steadily above the plate, then gradually tilting it to the side, observing the sliding of the sample on the spoon, and taking photos of its steady state and tilting sliding state respectively. Next, the fork drip test was performed by observing the flow behavior of the sample on the fork tines and recording the results. Finally, the fork pressure test was performed by applying pressure to the sample surface with the thumb through the fork, and taking photos to record the results.

[0068] Figure 9 The International Dysphagia Diet Standardization test results for the 3D printed samples of Examples 1-4 and Comparative Example 1. As can be seen from the figure, the 3D printed samples of soybean proteinase aggregate-citrus pectin at a ratio of 3:2 and 3:3 can maintain a relatively complete shape on the spoon, and when the spoon is tilted downward or slightly shaken, the sample completely falls off and there is no residue, indicating that it has a certain cohesiveness, and it remains on the top of the fork without flowing down or dripping from the fork gap. In the fork pressure test, all samples formed clearer pressure marks with increasing pectin concentration, the food was easily separated through the fork gap, and the force required to separate the samples did not reach the level of the thumb nail turning white. In addition, the samples could not restore their original shape when the fork was removed. The 3D printed samples of soybean proteinase aggregate-citrus pectin at a ratio of 3:0, 3:0.5 and 3:1 meet the standard level 4 for dysphagia, and the 3D printed samples of soybean proteinase aggregate-citrus pectin at a ratio of 3:2 and 3:3 meet the standard level 5 for dysphagia. Therefore, the 3D printed samples using soybean proteinase aggregate-citrus pectin at a ratio of 3:2 and 3:3 HIPEs as 3D printing ink are safer for the dysphagia population.

[0069] The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0070] The foregoing description of the disclosed embodiments enables a person skilled in the art to make or use the application. Modifications of these embodiments will occur to persons of skill in the art, and that the appended claims are intended to cover all such modifications that do not depart from the true spirit and scope of the application. Therefore, the application is not limited to the embodiments shown but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for preparing a protease-catalyzed aggregate-citrus pectin-based high internal phase emulsion suitable for 3D printing, characterized in that the steps include... include: Mix soybean protease aggregates with water, disperse evenly, adjust the pH to 10.0-12.0, stir for 0.5-1 h, and then adjust the pH to 7.0 to obtain a soybean protease aggregate dispersion. Citrus pectin was added to the soybean protease aggregate dispersion, and after mixing, soybean protease aggregate-citrus pectin stabilizer was obtained. After mixing the soybean protease-aggregator-citrus pectin stabilizer and the oil phase, homogenization was performed to obtain the protease-aggregator-citrus pectin-based high internal phase emulsion.

2. The preparation method according to claim 1, characterized in that, The preparation steps of the soybean protease-promoting aggregate include: Soy protein isolate was dissolved in water, enzymatically hydrolyzed, and the pH was adjusted to 7.

0. The enzyme was then inactivated by boiling water bath, centrifuged, and the insoluble precipitate was collected. After washing and drying, the soy protein-catalyzed aggregate was obtained.

3. The preparation method according to claim 2, characterized in that, The enzymatic hydrolysis treatment is performed at a pH of 6.0-9.0, a temperature of 40-60℃, and a time of 6-24 hours. And / or, the enzyme used in the enzymatic hydrolysis treatment includes alkaline protease or Novozymes Protamex complex protease, and the amount of enzyme added is 0.1-1.0% of the soybean protein isolate. And / or, the drying is freeze-drying.

4. The preparation method according to claim 1, characterized in that, The concentration of the soybean protease-promoting aggregate dispersion is 2-4 wt%; And / or, the mass ratio of the soybean protease-promoting aggregate dispersion to citrus pectin is 3:0.5-3.

5. The preparation method according to claim 1, characterized in that, The mixing process includes the following steps: After mixing citrus pectin with soybean protease aggregate dispersion, the pH was adjusted to 7.0 under magnetic stirring at 1000 rpm and maintained at pH equilibrium for 1 h to obtain the soybean protease aggregate-citrus pectin stabilizer.

6. The preparation method according to claim 1, characterized in that, The volume ratio of the soybean protease-aggregator-citrus pectin stabilizer to the oil phase is 1:3; And / or, the oil phase is vegetable oil; And / or, the homogenization process is performed at a rotation speed of 6000-10000 rpm for a time of 60-120 s.

7. A protease-catalyzed aggregate-citrus pectin-based high internal phase emulsion suitable for 3D printing, characterized in that, The protease-catalyzed aggregate-citrus pectin-based high internal phase emulsion suitable for 3D printing is prepared by the preparation method according to any one of claims 1-6.

8. The application of the protease-catalyzed aggregate-citrus pectin-based high internal phase emulsion for 3D printing as described in claim 7 in food 3D printing.

9. A 3D-printed food product, characterized in that, The raw materials include the protease-catalyzed aggregate-citrus pectin-based high internal phase emulsion as described in claim 7.

10. A method for preparing the above-mentioned 3D printed food, characterized in that, The 3D printing ink was prepared using the protease-catalyzed aggregate-citrus pectin-based high internal phase emulsion as described in claim 7.

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