Low-oil-phase high-viscoelastic emulsion gel as well as preparation method and application thereof

Abstract

The invention discloses low-oil-phase high-viscoelastic emulsion gel as well as a preparation method and application thereof, and relates to the technical field of food. According to the method, buckwheat protein microgel is used as a Pickering emulsifier, polysaccharide is used as a water-phase thickener, soybean oil, sesame oil and the like are used as an oil phase to construct a Pickering emulsion, a protein and polysaccharide interpenetrating double-network structure is constructed by adjusting the ratio of the emulsifier to the thickener, and the stability and viscoelasticity of the emulsion are flexibly regulated and controlled. The prepared emulsion gel is lower in oil phase fraction, the emulsion has excellent viscoelasticity under the oil phase content of 5%-50%, meanwhile, the emulsion gel can be used for constructing customized food through 3D printing, and effective reference is provided for development of novel low-fat food.

Description

Technical Field

[0001] The invention relates to the field of food technology, in particular to a low-oil-phase high-viscoelastic emulsion gel and a preparation method and application thereof. Background Art

[0002] 3D printing technology has significant advantages in the field of personalized food customization and improvement of people with dysphagia. The successful preparation of 3D printed food often depends on the extrudability and self-supporting properties of edible inks. Therefore, the preparation of bio-based inks with excellent viscoelastic properties can improve the shape, texture, taste and functional properties of 3D printed food, which is of great significance for the development of new 3D foods.

[0003] Emulsion gel is a semi-solid emulsion with a gel network structure. It mainly converts liquid emulsion into gel-like emulsion through droplet aggregation and interface network regulation. It has broad application prospects in the development of low-fat foods and delivery of active substances. Combining emulsion gel with 3D printing technology provides a new idea for preparing edible emulsion gel with good stability and processability. At present, the emulsion gel that can be 3D printed is mainly a high internal phase emulsion. CN114532413A discloses an emulsion gel for 3D printing of fat substitutes and a preparation method thereof. Negatively charged glycyrrhizic acid is adsorbed on the water-oil interface, and then positively charged chitosan is added to generate electrostatic cross-linking between oil droplets to form a three-dimensional network structure, and an emulsion gel is prepared. It is used as 3D printing ink, and the printed emulsion gel type can be used as a substitute for traditional plastic fat. However, the oil content in the emulsion gel is 70% (v / v). Although the emulsion with a high oil content has good viscoelasticity and stability, its high oil content is not suitable for people who pursue low-fat healthy food. In addition, excessive fat intake not only affects the normal metabolism of the digestive system, but also causes a variety of diseases.

[0004] CN116138346A discloses a novel 3D-printed plant protein-based emulsion gel as a fat substitute, a preparation method and application thereof, which overcomes the defect of plant protein not being formed in 3D printing by adding polysaccharides to the plant protein to cause cross-linking between the emulsion droplets. Among them, the oil phase in the plant protein-based emulsion gel accounts for 30-85%, and still has a high oil content. Emulsion gels with lower oil content will result in lower cohesion of the gel network structure, making the emulsion show high fluidity and poor viscoelasticity, which in turn causes the food emulsion to have poor shape, texture, taste and functional properties. Therefore, developing an emulsion gel with a low oil phase and high viscoelasticity, and combining it with 3D printing technology to achieve personalized customization of the emulsion gel is of great significance for the development of healthy foods. Summary of the invention

[0005] The invention provides a low-oil-phase high-viscoelastic emulsion gel and a preparation method and application thereof. The emulsion gel has the characteristics of low oil phase and high viscoelasticity.

[0006] The present invention first provides a method for preparing a low-oil-phase high-viscoelastic emulsion gel, comprising:

[0007] Buckwheat protein microgel and polysaccharide are dispersed in an aqueous phase to form a composite dispersion, which is then blended with oil to obtain an emulsion gel;

[0008] The volume fraction of the oil is 1-50%.

[0009] Preferably, the polysaccharide comprises any one or more of carboxylated cellulose nanofibers, carboxymethyl cellulose, chitosan, starch, gum arabic, carrageenan, pectin, agar, gellan gum, alginic acid or locust bean gum.

[0010] Preferably, the oil phase comprises one or more of soybean oil, sesame oil, olive oil, sunflower oil, camellia oil, coconut oil, rice bran oil, peanut oil, castor oil, rapeseed oil, Antarctic krill oil, linseed oil, essential oil, medium-chain triglycerides or oils with functional active substances.

[0011] Preferably, the functionally active substance in the oil having functionally active substances is curcumin, ginsenoside, quercetin or astaxanthin.

[0012] Preferably, the mixing method is stirring, high-speed shearing, high-pressure homogenization or high-pressure microfluidization.

[0013] Preferably, the volume ratio of the buckwheat protein microgel to the polysaccharide is (3-7):(3-7).

[0014] Preferably, the mixing speed is 3000-30000 rpm, and the mixing time is 0.5-60 min.

[0015] Preferably, the method for preparing the buckwheat protein microgel comprises:

[0016] Buckwheat protein is added to deionized water to form a dispersion with a concentration of 3-30%, and magnetic stirring is performed for 0.5-3 hours. Then, the dispersion is placed in a refrigerator for hydration for 12-48 hours. The pH of the hydrated solution is adjusted to 2 with HCL, and the solution is heated at 60-100° C. for 1-10 hours. The solution is quickly taken out and placed in ice water for cooling until it reaches an inverted non-flowing state, thereby obtaining buckwheat protein microgel (BPM).

[0017] The present invention also provides a low-oil-phase high-viscoelastic emulsion gel obtained by the above preparation method.

[0018] The present invention also provides application of the low-oil phase high-viscoelastic emulsion gel in the field of 3D printing customized food.

[0019] Beneficial effects of the present invention

[0020] (1) The present invention uses buckwheat protein microgel as an emulsifier and polysaccharide as a thickener, and utilizes the synergistic effect between buckwheat protein microgel and polysaccharide to construct a double network structure in which the protein network and the polysaccharide network penetrate each other, embeds the oil droplets into the spatial network structure of the cross-linked polymer, and promotes the bridging flocculation aggregation between the droplets, thereby preparing an emulsion gel with low oil phase and high viscoelasticity.

[0021] (2) The raw materials involved in the present invention are widely available, and the process is simple to operate and low in cost.

[0022] (3) The present invention can prepare fat substitutes by 3D printing, which has significant advantages in personalized food customization, improving dysphagia and delivering active substances. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of the preparation process of the emulsion gel of Example 1 (B3C7);

[0024] Figure 2 The appearance, optical microscope, potential of Example 1 (B3C7), Example 2 (B5C5), Example 3 (B7C3), Comparative Example 1 (BPM), Comparative Example 2 (CNF) and the appearance photos of Comparative Example 3 (zein);

[0025] Figure 3 Laser confocal microscopy images of Example 1 (B3C7), Example 2 (B5C5), Example 3 (B7C3), Comparative Example 1 (BPM), and Comparative Example 2 (CNF);

[0026] Figure 4 3D printed images of Example 1 (B3C7), Example 2 (B5C5), Example 3 (B7C3), Comparative Example 1 (BPM), and Comparative Example 2 (CNF);

[0027] Figure 5 3D print different model pictures for Example 1 (B3C7);

[0028] Figure 6 The rheology of Example 1 (B3C7), Example 2 (B5C5), Example 3 (B7C3), Comparative Example 1 (BPM), and Comparative Example 2 (CNF);

[0029] Figure 7 The appearance, optical microscope and 3D printing images of emulsions with different oil phase fractions of Example 7 (5%), Example 8 (10%), Example 1 (30%) and Example 7 (50%).

[0030] Figure 8 The appearance, microstructure and 3D printed product photos of the emulsion gels under different types of oils of Example 10 (Antarctic krill oil), Example 11 (linseed oil), Example 12 (olive oil) and Example 13 (sunflower oil). DETAILED DESCRIPTION

[0031] The present invention first provides a method for preparing a low-oil-phase high-viscoelastic emulsion gel, comprising:

[0032] First, buckwheat protein microgel is prepared. The method for preparing the buckwheat protein microgel preferably comprises: adding buckwheat protein to deionized water to prepare a dispersion with a concentration of 3-30%, stirring with a magnetic force for 0.5-3h, preferably 3h, and then placing in a refrigerator at 4°C for hydration for 12-48h, preferably 24h, adjusting the pH of the hydrated solution to 2 with 1mol / L HCL, heating at 60-100°C for 1-10h, preferably 100°C for 5h, and quickly taking out and placing in ice water for cooling until it reaches an inverted non-flowing state, thereby obtaining buckwheat protein microgel (BPM);

[0033] The buckwheat protein microgel prepared as above is mixed and dispersed with polysaccharide in an aqueous phase to form a composite dispersion, wherein before mixing, the buckwheat protein microgel and the polysaccharide are respectively dissolved in water and stirred evenly to obtain a buckwheat protein microgel solution and a polysaccharide dispersion, wherein the concentration of the buckwheat protein microgel solution is preferably 1-10.0wt%, more preferably 5wt%; the concentration of the polysaccharide dispersion is preferably 1-10.0wt%, more preferably 5wt%, and the polysaccharide is preferably any one or more of carboxylated cellulose nanofibers, carboxymethyl cellulose, chitosan, starch, gum arabic, carrageenan, pectin, agar, gellan gum, alginate or locust bean gum, more preferably carboxylated cellulose nanofibers; the volume ratio of buckwheat protein microgel to polysaccharide in the composite dispersion is preferably (3-7):(3-7), more preferably 3:7, 5:5 or 7:3.

[0034] The oil phase is added to the composite dispersion and mixed to obtain a low-oil-phase high-viscoelastic emulsion gel, wherein the volume fraction of the oil phase is 1%-50%, preferably 5%, 10%, 30% and 50%, and the oil phase is preferably one or more of soybean oil, sesame oil, olive oil, sunflower seed oil, camellia oil, coconut oil, rice bran oil, peanut oil, castor oil, rapeseed oil, Antarctic krill oil, linseed oil, essential oil, medium-chain triglycerides or oil with functional active substances, more preferably soybean oil, Antarctic krill oil or rice bran oil, and the functional active substance in the oil with functional active substances is preferably curcumin, ginsenoside, quercetin or astaxanthin.

[0035] The mixing method with the oil phase is not particularly limited, and is preferably stirring, high-speed shearing, high-pressure homogenization or high-pressure microfluidization, more preferably high-speed shearing, wherein the condition of using a high-speed homogenizer is preferably shearing at 3000-30000 rpm for 0.5-60 min, more preferably shearing at 15000 rpm for 2 min.

[0036] The present invention also provides a low-oil-phase high-viscoelastic emulsion gel obtained by the above preparation method.

[0037] The present invention also provides application of the low-oil phase high-viscoelastic emulsion gel in the field of 3D printing customized food.

[0038] The present invention is further described in detail below in conjunction with the examples and with reference to the data. The following examples are only for illustrating the present invention, and are not intended to limit the scope of the present invention in any way. The raw materials involved in the examples are all commercially available.

[0039] Example 1

[0040] (1) Preparation of buckwheat protein microgel: Buckwheat protein was added to deionized water to form a 5% dispersion, magnetically stirred for 3 h, and then placed in a refrigerator at 4°C for 24 h. The pH of the hydrated solution was adjusted to 2 with 1 mol / L HCL, heated at 100°C for 5 h, and quickly taken out and cooled in ice water until it reached an inverted non-flowing state, thereby obtaining buckwheat protein microgel (BPM);

[0041] (2) The prepared buckwheat protein microgel and carboxylated cellulose nanofibers were added to deionized water respectively, and BPM and CNF dispersions with a concentration of 5.0 wt% were prepared, and they were mixed to obtain a composite aqueous phase composed of BPM and CNF, and the volume ratio of BPM dispersion to CNF dispersion in the aqueous phase was 3:7.

[0042] (3) 6 mL of soybean oil was added to the composite aqueous phase with a total volume of 14 mL, and a high-speed homogenizer was used to homogenize at 15000 rpm for 2.0 min to obtain an emulsion. The volume fraction of the oil phase was 30%. The emulsion prepared above did not stratify when placed upright, did not flow when placed upside down, and had good stability. It can be seen from 3D printing that the printed product did not collapse and showed clear texture, which could well replicate the "Tetris" and "cake embryo" models. The preparation process of Example 1 is as follows Figure 1 shown.

[0043] Example 2

[0044] The experimental conditions and steps are the same as those in Example 1, except that the volume ratio of the BPM dispersion to the CNF dispersion in the aqueous phase in step (2) of Example 1 is adjusted to 5:5. The emulsion prepared above does not stratify when placed upright, does not flow when placed upside down, and has good stability.

[0045] Example 3

[0046] The experimental conditions and steps are the same as those in Example 1, except that the volume ratio of the BPM dispersion to the CNF dispersion in the aqueous phase in step (2) of Example 1 is adjusted to 7:3. The emulsion prepared above does not stratify when placed upright, does not flow when placed upside down, and has good stability.

[0047] Example 4

[0048] The experimental conditions and steps were the same as those in Example 1, except that the buckwheat protein microgel and carboxylated cellulose nanofibers prepared in step (2) of Example 1 were added to deionized water to prepare BPM and CNF dispersions with a concentration of 1.0 wt%, which were mixed to obtain a composite aqueous phase, in which the volume ratio of the BPM dispersion to the CNF dispersion in the aqueous phase was 3:7.

[0049] Example 5

[0050] The experimental conditions and steps were the same as those in Example 1, except that the buckwheat protein microgel and carboxylated cellulose nanofibers prepared in step (2) of Example 1 were added to deionized water to prepare BPM and CNF dispersions with a concentration of 3.0 wt%, which were mixed to obtain a composite aqueous phase, in which the volume ratio of the BPM dispersion to the CNF dispersion in the aqueous phase was 3:7.

[0051] Example 6

[0052] The experimental conditions and steps were the same as those in Example 1, except that the buckwheat protein microgel and carboxylated cellulose nanofibers prepared in step (2) of Example 1 were added to deionized water to prepare BPM and CNF dispersions with a concentration of 7.0 wt%, which were mixed to obtain a composite aqueous phase, in which the volume ratio of the BPM dispersion to the CNF dispersion in the aqueous phase was 3:7.

[0053] Example 7

[0054] The experimental conditions and steps are the same as those of Example 1, except that the volume of soybean oil in step (3) of Example 1 is adjusted to 0.74 mL, at which time the oil phase fraction is 5%, and the emulsion is sheared at 15000 rpm for 2 min to prepare a Pickering emulsion. The emulsion prepared above does not stratify when placed upright, does not flow when placed upside down, and has good stability.

[0055] Example 8

[0056] The experimental conditions and steps are the same as those of Example 1, except that the volume of soybean oil in step (3) of Example 1 is adjusted to 1.55 mL, at which time the oil phase fraction is 10%, and the emulsion is sheared at 15000 rpm for 2 min to prepare a Pickering emulsion. The emulsion prepared above does not stratify when placed upright, does not flow when placed upside down, and has good stability.

[0057] Example 9

[0058] The experimental conditions and steps are the same as those of Example 1, except that the volume of soybean oil in step (3) of Example 1 is adjusted to 14 mL, at which time the oil phase fraction is 50%, and the emulsion is sheared at 15000 rpm for 2 min to prepare a Pickering emulsion. The emulsion prepared above does not stratify when placed upright, does not flow when placed upside down, and has good stability.

[0059] Example 10

[0060] The experimental conditions and steps are the same as those in Example 1, except that 6 mL of Antarctic krill oil is used as the oil phase in step (3) of Example 1, and the other conditions remain unchanged to prepare a Pickering emulsion. The emulsion prepared above does not stratify when placed upright, does not flow when placed upside down, and has good stability.

[0061] Embodiment 11

[0062] The experimental conditions and steps are the same as those in Example 1, except that 6 mL of linseed oil is used as the oil phase in step (3) of Example 1, and the other conditions remain unchanged to prepare a Pickering emulsion. The emulsion prepared above does not stratify when placed upright, does not flow when placed upside down, and has good stability.

[0063] Example 12

[0064] The experimental conditions and steps are the same as those in Example 1, except that 6 mL of olive oil is used as the oil phase in step (3) of Example 1, and the other conditions remain unchanged to prepare a Pickering emulsion. The emulsion prepared above does not stratify when placed upright, does not flow when placed upside down, and has good stability.

[0065] Example 13

[0066] The experimental conditions and steps are the same as those in Example 1, except that 6 mL of sunflower seed oil is used as the oil phase in step (3) of Example 1, and the other conditions remain unchanged to prepare a Pickering emulsion. The emulsion prepared above does not stratify when placed upright, does not flow when placed upside down, and has good stability.

[0067] Embodiment 14

[0068] The experimental conditions and steps are the same as those in Example 1, except that the carboxylated cellulose nanofibers in step (2) of Example 1 are replaced with hydroxypropyl methyl starch, and the other conditions remain unchanged to prepare a Pickering emulsion. The emulsion prepared above does not stratify when placed upright, does not flow when placed upside down, and has good stability.

[0069] Embodiment 15

[0070] The experimental conditions and steps are the same as those in Example 1, except that the carboxylated cellulose nanofibers in step (2) of Example 1 are replaced with carboxymethyl cellulose, and the other conditions remain unchanged to prepare a Pickering emulsion. The emulsion prepared above does not stratify when placed upright, does not flow when placed upside down, and has good stability.

[0071] Example 16

[0072] The experimental conditions and steps are the same as those in Example 1, except that the carboxylated cellulose nanofibers in step (2) of Example 1 are replaced with gum arabic, and the other conditions remain unchanged to prepare a Pickering emulsion. The emulsion prepared above does not stratify when placed upright, does not flow when placed upside down, and has good stability.

[0073] Embodiment 17

[0074] The experimental conditions and steps are the same as those in Example 1, except that the carboxylated cellulose nanofibers in step (2) of Example 1 are replaced with pectin, and the other conditions remain unchanged to prepare a Pickering emulsion. The emulsion prepared above does not stratify when placed upright, does not flow when placed upside down, and has good stability.

[0075] Comparative Example 1

[0076] The experimental conditions and steps are the same as those in Example 1, except that the volume ratio of the BPM dispersion to the CNF dispersion in the aqueous phase in step (2) of Example 1 is adjusted to 1:0, 6 mL of soybean oil is added, wherein the volume fraction of the oil phase is 30%, and the mixture is sheared at 15000 rpm for 2 min on a high-speed shearing machine to prepare a Pickering emulsion. The emulsion prepared above exhibits oil-water separation and has extremely poor stability. The 3D printed product exhibits obvious fluidity, and the viscoelasticity of the emulsion is low, which is not suitable for 3D printing applications.

[0077] Comparative Example 2

[0078] The experimental conditions and steps are the same as those in Example 1, except that the volume ratio of the BPM dispersion to the CNF dispersion in the aqueous phase in step (2) of Example 1 is adjusted to 0:1, 6 mL of soybean oil is added, wherein the volume fraction of the oil phase is 30%, and the mixture is sheared at 15000 rpm on a high-speed shearing machine for 2 min to prepare a Pickering emulsion. The emulsion prepared above exhibits obvious oil separation and has extremely poor stability. The 3D printed product exhibits obvious fluidity. The viscoelasticity of the emulsion is low and is not suitable for 3D printing applications.

[0079] Comparative Example 3

[0080] The experimental conditions and steps were the same as those in Example 1, except that the buckwheat protein in step (1) of Example 1 was replaced with zein, and the dispersion obtained after heat treatment under the same conditions was inverted and flowed, and no microgel was formed, and the other conditions were unchanged to prepare a Pickering emulsion. The emulsion prepared above showed obvious oil precipitation and had extremely poor stability.

[0081] Figure 2 The appearance of the emulsions in Example 1 (B3C7), Example 2 (B5C5), Example 3 (B7C3), Comparative Example 1 (BPM), and Comparative Example 2 (CNF) ( Figure 2 A) Potential diagram ( Figure 2 B) and microstructure diagram ( Figure 2 C), it can be seen that neither buckwheat protein microgel nor carboxylated cellulose nanofibers alone can stabilize the Pickering emulsion, and both show oil-water separation. However, the droplet size of the emulsion stabilized by the two is relatively uniform and closely arranged, showing good stability. The Zeta potential of the emulsion changes from negative to positive with the increase of CNF content, indicating that the two have electrostatic interaction.

[0082] like Figure 3 The microstructures of Example 1 (B3C7), Example 2 (B5C5), Example 3 (B7C3), Comparative Example 1 (BPM), and Comparative Example 2 (CNF) were further observed by CLSM, wherein (a) shows the CLSM image of oil after staining with Nile red, (b) shows the CLSM image of buckwheat protein microgel after staining with Nile blue, (c) shows the CLSM image of carboxylated cellulose nanofibers after staining with Calcofluwhite, (d) shows the superimposed image of buckwheat protein microgel and carboxylated cellulose nanofibers after staining, and (e) shows the superimposed image of oil, buckwheat protein microgel and carboxylated cellulose nanofibers after staining. The protein cross-linked network formed by BPM in the emulsion of Example 1 (B3C7) is relatively dense, which effectively improves the viscoelasticity and stability of the emulsion.

[0083] Figure 4The rheological properties of the latex gel are given, where Figure 4 (A) is the graph showing the change of apparent viscosity (η) with shear rate. Figure 4 (B) is the graph showing the change of storage modulus and loss modulus with stress. Figure 4 (C) is the graph showing the variation of storage modulus (G′) with frequency. Figure 4 (D) is a graph showing the change in loss modulus (G′) with frequency. It can be seen from the figure that the emulsion gel synergistically stabilized by buckwheat protein microgel and carboxylated cellulose nanofibers has good viscoelasticity.

[0084] Figure 5 The 3D printing pictures of BPM and CNF synergistically stabilized emulsions at different ratios are shown, in which two models, "Tetris" and "cake embryo", are printed. It can be clearly observed from the figure that the sample printed by the emulsion of comparative example 1 (BPM) has obvious collapse, which is not suitable for 3D printing applications. In the emulsion of comparative example 2 (CNF), it can be observed that the printed product has obvious oil precipitation and collapse. For the emulsion gel synergistically stabilized by BPM and CNF, the viscoelasticity and 3D printing properties of the emulsion are gradually improved with the increase of CNF.

[0085] In order to further confirm the excellent 3D printing properties of the emulsion in Example 1 (B3C7), 3D printing of different complex models was performed. The results are as follows: Figure 6 As shown in the figure, it can be seen that the latex gel exhibits good layer-by-layer stacking and self-supporting properties when printing different models, and the shapes of all printed products are very close to the preset models, which further confirms the application prospects of B3C7 latex gel as edible ink in the field of 3D printing.

[0086] Example 7, Example 8, Example 1 and Example 9 are emulsion gels with oil phase fractions of 5%, 10%, 30% and 50%, respectively, and their appearance ( Figure 7 A) Microstructure ( Figure 7 B) and 3D printed product images ( Figure 7 C) Figure 7 As shown in the figure. It can be seen from the figure that the emulsion does not flow when inverted at different oil phase fractions, indicating that it has good stability and viscoelasticity. In addition, from the appearance of the printed products, it can be seen that the emulsion gels with different oil phase fractions all show good layer-by-layer stacking and self-supporting properties, and the shapes of all printed products are very close to the preset model, further confirming the application prospects of the emulsion gel in the field of low-fat food and 3D printing.

[0087] Examples 10-13 are emulsion gels prepared using different types of oils. Figure 8 The appearance of emulsion gel under different types of oil ( Figure 8 A) Microstructure ( Figure 8B) and 3D printed product photos ( Figure 8 C). As can be seen from the figure, the emulsions with different types of oil as the oil phase also have excellent viscoelasticity and 3D printing properties, indicating that the emulsion gel in the present invention has high universality and versatility, can be used in a variety of scenarios, and has good application prospects.

Claims

1. A method for preparing a low-oil phase high-viscoelastic emulsion gel, characterized in that: include: Buckwheat protein microgel and polysaccharide are dispersed in an aqueous phase to form a composite dispersion, which is then blended with oil to obtain an emulsion gel; The volume fraction of the oil is 1-50%.

2. The method for preparing a low-oil-phase high-viscoelastic emulsion gel according to claim 1, characterized in that: The polysaccharide comprises any one or more of carboxylated cellulose nanofibers, carboxymethyl cellulose, chitosan, starch, gum arabic, carrageenan, pectin, agar, gellan gum, alginic acid or locust bean gum.

3. The method for preparing a low oil phase high viscoelastic emulsion gel according to claim 1, characterized in that: The oil phase includes one or more of soybean oil, sesame oil, olive oil, sunflower seed oil, camellia oil, coconut oil, rice bran oil, peanut oil, castor oil, rapeseed oil, Antarctic krill oil, linseed oil, essential oil, medium chain triglyceride or oil with functional active substances.

4. The method for preparing a low-oil-phase high-viscoelastic emulsion gel according to claim 3, characterized in that: The functional active substance in the oil with functional active substances is curcumin, ginsenoside, quercetin or astaxanthin.

5. The method for preparing a low oil phase high viscoelastic emulsion gel according to claim 1, characterized in that: The mixing method is stirring, high-speed shearing, high-pressure homogenization or high-pressure microfluidization.

6. The method for preparing a low-oil-phase high-viscoelastic emulsion gel according to claim 1, characterized in that: The volume ratio of the buckwheat protein microgel to the polysaccharide is (3-7):(3-7).

7. The method for preparing a low-oil-phase high-viscoelastic emulsion gel according to claim 1, characterized in that: The mixing speed is 3000-30000 rpm, and the mixing time is 0.5-60 min.

8. The method for preparing a low-oil-phase high-viscoelastic emulsion gel according to claim 1, characterized in that: The method for preparing the buckwheat protein microgel comprises: Buckwheat protein is added to deionized water to form a dispersion with a concentration of 3-30%, and magnetic stirring is performed for 0.5-3 hours. Then, the dispersion is placed in a refrigerator for hydration for 12-48 hours. The pH of the hydrated solution is adjusted to 2 with HCL, and the solution is heated at 60-100° C. for 1-10 hours. The solution is quickly taken out and placed in ice water for cooling until it reaches an inverted non-flowing state, thereby obtaining buckwheat protein microgel (BPM).

9. The low-oil phase high-viscoelastic emulsion gel obtained by the preparation method of claim 1.

10. Application of the low-oil-phase high-viscoelastic emulsion gel according to claim 9 in the field of 3D printed customized food.

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