A thermosensitive two-phase structured emulsion gel and its preparation method and application

Abstract

The present invention discloses a thermosensitive two-phase structured emulsion gel and a preparation method and application thereof. The emulsion gel uses a solution of glycyrrhizic acid or a glycyrrhizic acid derivative as an aqueous phase and a lipophilic gelling agent dissolved in liquid oil as an oil phase, and utilizes the characteristics of two-phase thermal melting and condensation to prepare a thermosensitive two-phase structured emulsion gel. The emulsion gel has excellent mechanical properties and temperature response characteristics, can effectively load and protect hydrophilic / hydrophobic active substances, and achieve controlled release of flavor substances. The invention has a simple preparation process, mild conditions, and is easy to mass produce. It can be used as a plastic fat substitute in future food processing, cosmetics, medicine, and other fields such as artificial meat.

Description

Technical Field

[0001] The invention belongs to the technical field of food, medicine and cosmetics processing, and specifically relates to a temperature-sensitive two-phase structured emulsion gel and a preparation method and application thereof. Background Art

[0002] Emulsion gel, also known as gelled emulsion, is a semisolid material with a certain viscoelasticity composed of a dispersed phase (internal phase) and a continuous phase (external phase). Due to its special structure and properties, emulsion gel is widely used in food, cosmetics, materials, medicine and other fields. A large number of studies have shown that emulsion gel can be used as a new liquid oil structuring strategy to prepare semisolid or solid fat substitutes to replace plastic fats in food, thereby reducing health problems such as cardiovascular and cerebrovascular diseases and chronic metabolic diseases caused by trans fats and saturated fats used in food processing. In recent years, the research on future food processing and characteristics such as plant meat and cell cultured meat has become a research hotspot in the modern food industry, which helps to alleviate the pressure on resources, environment, health, ethics and other aspects brought about by the traditional meat production process, and solve the problems of sustainable meat supply demand and carbon emissions. For the quality of artificial meat such as plant meat and cell cultured meat, adding structured fat substitutes with similar characteristics to animal fat is extremely critical, which can significantly improve the taste texture (such as juiciness and real meat taste), nutritional flavor and final product sensory acceptance of artificial meat products. Animal fat is a structural tissue in which fat cells are combined with the inside of reticular connective fiber bundles. Its essence is an emulsion-filled gel. Emulsion gel is a relatively simple and highly operable method to achieve the structuring of liquid oils. It realizes the plasticity of liquid vegetable oil by constructing a gel network structure in the emulsion system, thereby obtaining vegan fat with similar properties to traditional animal fat, so as to better provide sufficient meaty taste for artificial meat products such as plant meat. In addition, emulsion gel can also be used as a delivery carrier for a variety of hydrophilic and hydrophobic active substances (such as vitamins, pigments, plant sterols, polyphenols, etc.), and can exhibit sustained aroma release capabilities. Therefore, emulsion gel has obvious advantages in the preparation of animal fat simulation substitutes.

[0003] A Chinese patent application for a natural amphiphilic small molecule induced emulsion gel and its rapid preparation method discloses the successful use of the self-assembly characteristics of natural food-grade small molecule glycyrrhizic acid to obtain an emulsion gel with a semi-solid shape and good plasticity and spreadability, which can be used as a structured fat substitute. However, it does not have a wide temperature response range and controllable temperature responsiveness, and cannot effectively regulate its own texture characteristics through temperature; in addition, the emulsion gel cannot achieve the co-release of hydrophilic and hydrophobic active ingredients, limiting its practical application value. Compared with emulsion gels containing only a continuous aqueous phase gel network, dual-phase structured emulsion gels have unique two-phase structuring characteristics, forming a good gelation network structure in both the continuous aqueous phase and the dispersed oil phase, which can significantly improve the overall mechanical properties and temperature responsiveness of the emulsion gel, and enhance the co-protection and delivery of hydrophilic / hydrophobic active substances. Summary of the invention

[0004] In order to solve the problems that emulsion gels containing only a continuous aqueous phase gel network do not have a wide temperature response range and controllable temperature responsiveness, and cannot achieve the common release of hydrophilic and hydrophobic active ingredients. The purpose of the present invention is to provide a temperature-sensitive two-phase structured emulsion gel and its preparation method and application, specifically through the independent self-assembly characteristics of the oil phase and the water phase, adopting an efficient and simple one-step emulsification preparation method, while forming a structured network in the water phase and the oil phase, giving the emulsion gel high mechanical properties, a wider range of temperature response behavior and dual continuous structural characteristics, thereby expanding its application in the fields of food, cosmetics, etc. in the future.

[0005] The present invention relates to a method for preparing an edible two-phase structured emulsion gel with temperature sensitivity and high mechanical strength, and in particular to a method for regulating the temperature response behavior, structural characteristics and mechanical properties of the system by changing the composition and concentration of the water phase and the oil phase in the emulsion gel. The emulsion gel can be used as a traditional animal fat substitute or a structured oil soft material in the fields of future food (such as plant meat and cell cultured meat), cosmetics, etc.

[0006] In the thermosensitive dual-phase structured emulsion gel introduced in the present invention, the characteristics of glycyrrhizic acid or glycyrrhizic acid derivatives being able to self-assemble in the aqueous phase to form a glycyrrhizic acid fiber network, and the lipophilic gelling agent being able to self-assemble in the liquid oil to form a fat crystal network, are utilized. By simultaneously constructing a glycyrrhizic acid fiber network in the aqueous phase and a fat crystal network in the oil phase in the emulsion gel, the simulation of the animal fat structure and processing characteristics (such as fat melting during cooking) can be better achieved. Compared with traditional emulsion gels, the thermosensitive dual-phase structured emulsion gel prepared by the present invention has more superior performance, which greatly broadens the practical application of emulsion gels in the future food (such as plant meat and cell cultured meat), cosmetics and other fields.

[0007] The mechanism of the present invention is as follows: (1) Glycyrrhizic acid can self-assemble in water to form glycyrrhizic acid nanofibers, and the glycyrrhizic acid fibers further form a hydrogel with a three-dimensional network structure through intermolecular non-covalent forces (mainly hydrogen bonds). (2) The lipophilic gelling agent can self-assemble into a crystalline network structure in the oil phase, thereby forming an oil gel, i.e., structured oil. (3) The hydrogel formed by glycyrrhizic acid and the oil gel formed by the lipophilic gelling agent are subjected to heating, mixing and homogenizing treatment to form a new emulsion gel system with high mechanical properties, a bicontinuous structure and highly controllable temperature response behavior.

[0008] The present invention provides a method for preparing a temperature-sensitive two-phase structured emulsion gel, comprising the following steps:

[0009] (1) uniformly dispersing a certain amount of glycyrrhizic acid or a glycyrrhizic acid derivative in water, heating and stirring for a period of time to obtain a transparent glycyrrhizic acid solution or a glycyrrhizic acid derivative solution;

[0010] (2) Add the lipophilic gelling agent into the liquid oil at a certain ratio and concentration, heat and stir for a period of time until the oil phase is evenly dispersed, and obtain a uniformly dispersed oil phase.

[0011] (3) The glycyrrhizic acid solution or glycyrrhizic acid derivative solution obtained in step 1) and the oil phase containing the lipophilic gelling agent obtained in step 2) are mixed at a certain concentration to obtain a mixed system, heated for a period of time until the mixed system is completely dissolved, homogenized while hot, and then cooled to obtain a temperature-sensitive two-phase structured emulsion gel.

[0012] Preferably, the glycyrrhizic acid derivative in step 1) includes one of ammonium glycyrrhizinate, monopotassium glycyrrhizinate, dipotassium glycyrrhizinate and trisodium glycyrrhizinate.

[0013] Preferably, in step 1), the concentration of the glycyrrhizic acid solution or the glycyrrhizic acid derivative solution is 1wt%-8wt%, the heating and stirring temperature is 60-95°C, and the heating and stirring time is 5-30min.

[0014] Preferably, the lipophilic gel in step 2) comprises one or more of phytosterols, oryzanol, monoglyceride, stearic acid, palmitic acid, sorbitan tristearate, lecithin, dodecyl stearic acid, ricinoleic acid, candelilla wax, and beeswax.

[0015] Preferably, the liquid oil in step 2) includes one or more of sunflower oil, soybean oil, rapeseed oil, corn oil, olive oil, peanut oil, camellia oil, fish oil, algae oil and linseed oil.

[0016] Preferably, in step 2), the mass of the lipophilic gel accounts for 1wt%-30wt% of the mass of the oil phase, the temperature of the heating and stirring is 60-95°C, and the time of the heating and stirring is 5-30min.

[0017] Preferably, in step 3), the mass of the oil phase accounts for 10wt%-80wt% of the mass of the mixed system.

[0018] Preferably, in step 3), the heating temperature is 60-95° C., and the heating time is 5-30 min.

[0019] Preferably, in step 2), the homogenization speed is 5000-30000 rpm, and the homogenization time is 1-5 min.

[0020] Preferably, the cooling temperature in step 3) is 0-25° C. and the cooling time is 10-30 min.

[0021] The invention provides a temperature-sensitive two-phase structured emulsion gel prepared by the preparation method.

[0022] The present invention also provides application of the temperature-sensitive dual-phase structured emulsion gel in food, cosmetics or medicine.

[0023] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0024] 1. The thermosensitive dual-phase structured emulsion gel prepared by the present invention has high mechanical properties and can be used as an excellent plastic fat (such as traditional animal fat, coconut oil, palm oil and other saturated fats and trans fatty acids, etc.) substitute and hydrophilic / hydrophobic active controlled release material.

[0025] 2. The thermosensitive two-phase structured emulsion gel prepared by the present invention has a dual-continuous structure and good temperature sensitivity, a large temperature response range and highly controllable behavior, which can expand the application range of the emulsion gel.

[0026] 3. The present invention provides a method for preparing a temperature-sensitive two-phase structured emulsion gel, which expands the application of emulsion gel in the fields of food, cosmetics, medicine, etc., especially it can replace traditional animal fat in the processing of artificial meat such as plant meat and cell cultured meat.

[0027] 4. The preparation method of the temperature-sensitive two-phase structured emulsion gel provided by the present invention is simple, efficient, mild and pollution-free. The glycyrrhizic acid, glycyrrhizic acid derivatives and lipophilic gelling agents used are safe, edible and easily available. The prepared emulsion gel has a high unsaturated fat content and is rich in bioactive substances. It has a good improvement effect on cardiovascular and cerebrovascular diseases, chronic metabolic diseases, etc., and is a healthy, nutritious and sustainable plastic fat substitute product.

[0028] 5. The emulsion gel prepared by the present invention has excellent mechanical properties and temperature response characteristics, can effectively load and protect hydrophilic / hydrophobic active substances, and realize the controlled release of flavor substances. In addition, the preparation process of the present invention is simple, the conditions are mild, and it is easy to mass produce. It can be used as a plastic fat substitute in future food processing, cosmetics, medicine and other fields such as artificial meat. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1a It is a frequency scanning graph of the temperature-sensitive two-phase structured emulsion gel prepared from the plant sterol-oryzanol mixtures of different mass percentage concentrations (the total mass of the plant sterol-oryzanol mixture accounts for the mass of the oil phase) in Comparative Example 1 and Examples 1-4.

[0030] Figure 1b The temperature response phase diagram of the thermosensitive two-phase structured emulsion gel prepared from the plant sterol-oryzanol mixtures with different mass percentage concentrations (the total mass of the plant sterol-oryzanol mixture accounts for the mass of the oil phase) of Comparative Example 1 and Examples 1-4.

[0031] Figure 2 This is a frequency scanning diagram of the temperature-sensitive dual-phase structured emulsion gel prepared with different proportions of oryzanol and phytosterol in Examples 5-9.

[0032] Figure 3 This is a frequency scanning diagram of the temperature-sensitive two-phase structured emulsion gel prepared with different mass percentages of the oil phase in the total mixed system in Examples 10-14.

[0033] Figure 4 This is a frequency scanning diagram of the temperature-sensitive two-phase structured emulsion gel prepared with different concentrations of ammonium glycyrrhizinate solution in Examples 15-17.

[0034] Figure 5a This is a frequency scanning diagram of the temperature-sensitive two-phase structured emulsion gel prepared from monoglyceride of different mass percentage concentrations (the mass of monoglyceride to the mass of the oil phase) in Comparative Example 2 and Examples 18-22.

[0035] Figure 5b This is the temperature response phase diagram of the thermosensitive two-phase structured emulsion gel prepared in Comparative Example 2 and Examples 18-22 with a monoglyceride mass percentage concentration of 4 wt%.

[0036] Figure 6a The temperature-sensitive dual-phase structured emulsion gels prepared from monoglycerides of different mass percentage concentrations (the mass percentage of monoglycerides in the mass of the oil phase) in Comparative Example 3 and Examples 23-27 had a vitamin B content of 0.0447 W / m2 during storage. 12 Retention rate graph.

[0037] Figure 6bThis is a graph of the retention rate of β-carotene during storage of the thermosensitive two-phase structured emulsion gels prepared with monoglycerides of different mass percentage concentrations (the mass of monoglycerides accounts for the mass of the oil phase) in Comparative Example 3 and Examples 23-27.

[0038] Figure 7 The dynamic release curves of limonene in the thermosensitive dual-phase structured emulsion gel prepared with monoglyceride of different mass percentage concentrations (mass of monoglyceride as a percentage of the mass of the oil phase) in Comparative Example 4 and Examples 28-32 are shown. DETAILED DESCRIPTION

[0039] In order to better understand the present invention, the present invention is further described below in conjunction with the accompanying drawings and embodiments, but the embodiments of the present invention are not limited thereto.

[0040] In the following examples, the rheological determination method is as follows:

[0041] Rheological measurement: Small deformation rheological analysis was used to analyze the rheological properties of the emulsion. On the HAAKE-MARS60 rheometer, the emulsion gel was placed on the sample stage of the rheometer, and parallel plates were used for testing. The gap between the sample stage and the parallel plate is 1mm. First, a vibration experiment with amplitude scanning and frequency scanning was performed at 25°C to measure the changes in the yield stress (G′=G″), viscous modulus value (G″) and elastic modulus value (G′) of the sample. Then the sample was subjected to a temperature scan, the gel-sol transition temperature point (G′=G″) of each sample was recorded, and a unified phase diagram was made.

[0042] Comparative Example 1

[0043] (1) 0.32 g of ammonium glycyrrhizinate powder was uniformly dispersed in 3.68 g of deionized water, and stirred at 300 rpm for 10 min in a 60° C. water bath to obtain a clear and transparent 8 wt % ammonium glycyrrhizinate solution.

[0044] (2) 6 g of sunflower seed oil was stirred in a constant temperature water bath at 95° C. for 15 min to obtain an oil phase (the total mass of the phytosterol-oryzanol mixture accounted for 0 wt % of the mass of the oil phase).

[0045] (3) 4 g of ammonium glycyrrhizic acid solution was mixed with 6 g of oil phase to obtain a mixed system (the mass of the oil phase accounted for 60 wt% of the mass of the mixed system), heated at 95° C. for 5 min until the oil and water phases were completely dissolved, and homogenized at a speed of 20,000 rpm for 2 min while hot. Subsequently, the mixture was cooled in an ice bath at 4° C. for 20 min to obtain a temperature-sensitive structured emulsion gel prepared from ammonium glycyrrhizic acid.

[0046] Example 1

[0047] Example 1 A method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining ammonium glycyrrhizinate and phytosterol-oryzanol is the same as the preparation method of Comparative Example 1, except that in step (2), 0.18 g oryzanol and 0.12 g phytosterol are added to 5.7 g sunflower oil in a ratio of 6:4 (the total mass of the phytosterol-oryzanol mixture accounts for 5 wt% of the mass of the oil phase).

[0048] Example 2

[0049] Example 2 A method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining ammonium glycyrrhizinate and phytosterol-oryzanol is the same as the preparation method of Comparative Example 1, except that in step (2), 0.36 g oryzanol and 0.24 g phytosterol are added to 5.4 g sunflower oil in a ratio of 6:4 (the total mass of the phytosterol-oryzanol mixture accounts for 10 wt% of the mass of the oil phase).

[0050] Example 3

[0051] Example 3 A method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining ammonium glycyrrhizinate and phytosterol-oryzanol is the same as the preparation method of Comparative Example 1, except that in step (2), 0.72 g oryzanol and 0.48 g phytosterol are added to 4.8 g sunflower oil in a ratio of 6:4 (the total mass of the phytosterol-oryzanol mixture accounts for 20 wt% of the mass of the oil phase).

[0052] Example 4

[0053] Example 4 A method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining ammonium glycyrrhizinate and phytosterol-oryzanol is the same as the preparation method of Comparative Example 1, except that in step (2), 1.08 g oryzanol and 0.72 g phytosterol are added to 4.2 g sunflower oil in a ratio of 6:4 (the total mass of the phytosterol-oryzanol mixture accounts for 30 wt% of the mass of the oil phase).

[0054] The mechanical properties of emulsion gels are important indicators for evaluating whether they can be used as fat products or in cosmetics, pharmaceuticals, etc. The microstructure of the gel is closely related to its small deformation rheological characteristics and large deformation mechanical properties. The rheological properties (ability to resist small deformation) can be reflected by the viscoelastic modulus of the product. The G' value represents the energy stored in each deformation cycle, reflecting the elasticity and solid-like properties of the sample being tested, while the G" value reflects the viscosity and liquid-like properties of the sample.

[0055] Figure 1ais a frequency scan diagram of the emulsion gel prepared at 100Pa stress (determined according to the experimental results of stress scanning, within the linear viscoelastic region) with the mass percentage concentration of phytosterol-oryzanol (the percentage of the total mass of the phytosterol-oryzanol mixture to the mass of the oil phase) of 0wt%, 5wt%, 10wt%, 20wt% and 30wt%, respectively, Figure 1a It can be seen that the elastic modulus (G′) of all samples has always been significantly higher than the viscous modulus (G″), indicating that the prepared emulsion gel exhibits elastic solid-like properties. With the increase in the mass percentage concentration of the phytosterol-oryzanol mixture, the elastic modulus G′ and viscous modulus G″ of the sample both increase. When the mass percentage concentration of the phytosterol-oryzanol mixture increases from 0 to 30wt%, the elastic modulus can increase from 40000Pa to 400000Pa, indicating that the sample has super mechanical properties. At the same time, at high frequency, the sample still does not have a yield point (G′=G″), indicating that the emulsion gel does not undergo a gel-sol transition under high-rate deformation. This shows that the mechanical strength of the emulsion gel can be manipulated by simply changing the phytosterol and oryzanol content in the oil phase.

[0056] Excellent mechanical properties can maintain the structure of the latex gel, while wide thermal responsiveness can expand the practical application range of the latex gel. Through temperature scanning test (temperature range is 25-95°C), the gel-sol transition temperature (G′=G″) of each sample is taken, and the corresponding phase diagram is made. Figure 1b is the temperature response phase diagram of the emulsion gel prepared when the mass percentage concentration of the phytosterol-oryzanol mixture (the total mass of the phytosterol-oryzanol mixture accounts for the mass of the oil phase) is 0wt%, 5wt%, 10wt%, 20wt% and 30wt%, respectively, Figure 1b It can be seen that the emulsion gel containing 0wt%, 5wt% and 10wt% phytosterol-oryzanol in the oil phase slowly turns into a sol at 60°C due to the melting of the fiber network, and when the mass percentage concentration of the oil phase structuring agent (phytosterol-oryzanol mixture) is 20wt%, the gel-sol transition temperature is increased to 80°C, and when the mass percentage concentration of the oil phase structuring agent (phytosterol-oryzanol mixture) is 30wt%, the gel-sol transition temperature is about 90°C. This shows that with the increase of the mass percentage concentration of the oil phase structuring agent (phytosterol-oryzanol mixture), the structural network of the emulsion gel becomes tighter, and the thermal responsiveness of the emulsion gel can be regulated by changing the concentration of the phytosterol-oryzanol mixture.

[0057] The glycyrrhizic acid, phytosterols and oryzanol used in the experiment are safe and edible, and reasonable use is beneficial to human health. In addition, from the preparation method, it can be seen that the emulsion gel of the present invention is easy to prepare, the conditions are mild, and no toxic and harmful waste is generated, and it can be used for industrial production.

[0058] Example 5

[0059] (1) 0.32 g of dipotassium glycyrrhizinate powder was uniformly dispersed in 3.68 g of deionized water, and stirred at 300 rpm for 25 min in a 70° C. water bath to obtain a 8 wt % clear and transparent dipotassium glycyrrhizinate solution.

[0060] (2) 0.96 g of oryzanol and 0.24 g of phytosterol were added to 4.8 g of sunflower oil in a ratio of 8:2, and the mixture was stirred in a constant temperature water bath at 70° C. for 25 min until the phytosterol-oryzanol mixture was evenly dispersed in the sunflower oil to obtain an oil phase.

[0061] (3) 4 g of dipotassium glycyrrhizinate solution was mixed with 6 g of oil phase to obtain a mixed system (the mass of the oil phase accounted for 60 wt% of the mass of the mixed system), heated at 60° C. for 30 min until the oil and water phases were completely dissolved, and homogenized while hot for 5 min (rotation speed was 5000 rpm), followed by cooling in an ice bath at 2° C. for 15 min to obtain a temperature-sensitive two-phase structured emulsion gel prepared by combining dipotassium glycyrrhizinate and phytosterol-oryzanol.

[0062] Example 6

[0063] Example 6 The method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining dipotassium glycyrrhizinate and phytosterol-oryzanol is the same as the preparation method of Example 5, except that in step (2), 0.72 g oryzanol and 0.48 g phytosterol are added to 4.8 g sunflower oil in a ratio of 6:4.

[0064] Example 7

[0065] Example 7 A method for preparing a thermosensitive dual-phase structured emulsion gel prepared from dipotassium glycyrrhizinate and phytosterol-oryzanol is the same as the preparation method of Example 5, except that in step (2), 0.6 g oryzanol and 0.6 g phytosterol are added to 4.8 g sunflower oil in a ratio of 5:5.

[0066] Example 8

[0067] Example 8 The method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining dipotassium glycyrrhizinate and phytosterol-oryzanol is the same as the preparation method of Example 5, except that in step (2), 0.48 g oryzanol and 0.72 g phytosterol are added to 4.8 g sunflower oil in a ratio of 4:6.

[0068] Example 9

[0069] Example 9 A method for preparing a thermosensitive dual-phase structured emulsion gel prepared from dipotassium glycyrrhizinate and phytosterol-oryzanol is the same as the preparation method of Example 5, except that in step (2), 0.24 g oryzanol and 0.96 g phytosterol are added to 4.8 g sunflower oil in a ratio of 2:8.

[0070] Figure 2 The frequency scans of emulsion gels prepared by adding oryzanol and phytosterols to sunflower oil in mass ratios of 8:2, 6:4, 5:5, 4:6, and 2:8 are shown in FIG. Figure 2 It can be seen that at the same mass percentage concentration of oryzanol-oryzanol, the modulus values ​​of the emulsion gels prepared by adding oryzanol and phytosterols to sunflower oil in different proportions are relatively large, indicating that the emulsion gels under different proportions of phytosterols still have strong mechanical properties. At the same time, it can also be seen that the elastic modulus and viscous modulus of the emulsion gel prepared when the mass ratio of oryzanol to phytosterol is 6:4 are the largest.

[0071] Example 10

[0072] (1) 0.8 g of ammonium glycyrrhizinate powder was uniformly dispersed in 9.2 g of deionized water, and stirred at 300 rpm for 5 min under heating at 95° C. in a water bath to obtain a 8 wt % clear and transparent ammonium glycyrrhizinate solution.

[0073] (2) 1.2 g of oryzanol and 0.8 g of phytosterol were added to 8 g of soybean oil in a ratio of 6:4, and stirred in a constant temperature water bath at 95° C. for 30 min until the phytosterol-oryzanol mixture was evenly dispersed in the soybean oil to obtain an oil phase.

[0074] (3) 9 g of ammonium glycyrrhizinate solution was mixed with 1 g of oil phase to obtain a mixed system (the mass of the oil phase accounted for 10 wt% of the mass of the mixed system), heated at 75° C. for 15 min until the mixed system was completely dissolved, homogenized at 30,000 rpm while hot for 1 min, and then cooled in an ice bath at 4° C. for 20 min to obtain a temperature-sensitive two-phase structured emulsion gel prepared by combining ammonium glycyrrhizinate and phytosterol-oryzanol.

[0075] Embodiment 11

[0076] Example 11 is a method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining ammonium glycyrrhizinate and phytosterol-oryzanol, except that in step (3), 8 g of ammonium glycyrrhizinate solution is mixed with 2 g of oil phase to obtain a mixed system (the mass of the oil phase accounts for 20 wt% of the mass of the mixed system), and the rest is the same as the preparation method of Example 10.

[0077] Example 12

[0078] Example 12 is a method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining ammonium glycyrrhizinate and phytosterol-oryzanol, except that in step (3), 6 g of ammonium glycyrrhizinate solution is mixed with 4 g of oil phase to obtain a mixed system (the mass of the oil phase accounts for 40 wt% of the mass of the mixed system), and the rest is the same as the preparation method of Example 10.

[0079] Embodiment 13

[0080] Example 13 A method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining ammonium glycyrrhizinate and phytosterol-oryzanol is the same as the preparation method of Example 10, except that in step (3), 4 g of ammonium glycyrrhizinate solution is mixed with 6 g of oil phase to obtain a mixed system (the mass of the oil phase accounts for 60 wt% of the mass of the mixed system).

[0081] Embodiment 14

[0082] Example 14 is a method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining ammonium glycyrrhizinate and phytosterol-oryzanol, except that in step (3), 2 g of ammonium glycyrrhizinate solution is mixed with 8 g of oil phase to obtain a mixed system (the mass of the oil phase accounts for 80 wt% of the mass of the mixed system), and the rest is the same as the preparation method of Example 10.

[0083] Figure 3 The frequency scan diagrams of the emulsion gels prepared when the oil phase accounts for 10wt%, 20wt%, 40wt%, 60wt% and 80wt% of the total mixed system are shown in FIG. Figure 3 It can be seen that with the increase of oil phase content, the elastic modulus and viscous modulus of the emulsion gel increased significantly, and the enhancement amplitude was large. This shows that simply changing the oil phase content can control the mechanical properties of the emulsion gel.

[0084] Embodiment 15

[0085] (1) 0.08 g of ammonium glycyrrhizinate powder was uniformly dispersed in 3.92 g of deionized water, and stirred at 300 rpm for 30 min in a 70° C. water bath until a 2 wt % clear and transparent ammonium glycyrrhizinate solution was obtained.

[0086] (2) 0.72 g of oryzanol and 0.48 g of phytosterol were added to 4.8 g of sunflower oil in a ratio of 6:4, and the mixture was stirred in a constant temperature water bath at 60° C. for 30 min until the phytosterol-oryzanol mixture was evenly dispersed in the sunflower oil to obtain an oil phase.

[0087] (3) 4 g of ammonium glycyrrhizic acid solution was mixed with 6 g of oil phase to obtain a mixed system (the mass of the oil phase accounted for 60 wt% of the mass of the mixed system), heated at 95° C. for 30 min, homogenized at a speed of 20,000 rpm while hot for 2 min, and then cooled in an ice bath at 4° C. for 10 min to obtain a temperature-sensitive two-phase structured emulsion gel prepared by combining ammonium glycyrrhizic acid and phytosterol-oryzanol.

[0088] Example 16

[0089] Example 16 A method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining ammonium glycyrrhizate and phytosterol-oryzanol is the same as the preparation method of Example 15, except that in step (1), 0.16 g of ammonium glycyrrhizate powder is uniformly dispersed in 3.84 g of deionized water (to obtain a clear and transparent ammonium glycyrrhizate solution with a concentration of 4 wt %).

[0090] Embodiment 17

[0091] Example 17 A method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining ammonium glycyrrhizate and phytosterol-oryzanol is the same as the preparation method of Example 15, except that in step (1), 0.24 g of ammonium glycyrrhizate powder is uniformly dispersed in 3.76 g of deionized water (to obtain a clear and transparent ammonium glycyrrhizate solution with a concentration of 6 wt %).

[0092] Figure 4 is the frequency scanning diagram of the emulsion gel prepared by the ammonium glycyrrhizinate solution with the concentration of 2wt%, 4wt% and 6wt%, respectively. Figure 4 It can be seen that with the increase of the concentration of ammonium glycyrrhizinate solution, the modulus value of the prepared emulsion gel increases, and the increase is large, indicating that the emulsion gel prepared with different concentrations of ammonium glycyrrhizinate solution also has good mechanical properties.

[0093] Comparative Example 2

[0094] (1) 0.4 g of trisodium glycyrrhizinate powder was uniformly dispersed in 4.6 g of deionized water, and stirred at 300 rpm for 15 min in a water bath at 80° C. to obtain a 8 wt % clear trisodium glycyrrhizinate solution.

[0095] (2) 5 g of soybean oil was stirred in a constant temperature water bath at 80° C. for 10 min to obtain an oil phase (the mass of monoglyceride accounted for 0 wt % of the mass of the oil phase).

[0096] (3) 5 g of trisodium glycyrrhizinate solution and 5 g of oil phase were mixed to obtain a mixed system (the mass of the oil phase accounted for 50 wt% of the mass of the mixed system), heated at 80° C. for 10 min, homogenized at a speed of 20,000 rpm while hot for 2 min, and then cooled at room temperature of 25° C. for 30 min to obtain a temperature-sensitive structured emulsion gel prepared from trisodium glycyrrhizinate.

[0097] Embodiment 18

[0098] Example 18 is a method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining trisodium glycyrrhizinate and monoglyceride, except that in step (2), 0.05g of monoglyceride is added to 4.95g of soybean oil (the mass of monoglyceride accounts for 1wt% of the mass of the oil phase), and the rest is the same as the preparation method of Comparative Example 2.

[0099] Embodiment 19

[0100] Example 19: A method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining trisodium glycyrrhizinate and monoglyceride is the same as the preparation method of Comparative Example 2, except that in step (2), 0.1 g of monoglyceride is added to 4.9 g of soybean oil (the mass of monoglyceride accounts for 2 wt% of the mass of the oil phase).

[0101] Embodiment 20

[0102] Example 20: A method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining trisodium glycyrrhizinate and monoglyceride is the same as the preparation method of Comparative Example 2, except that in step (2), 0.2 g of monoglyceride is added to 4.8 g of soybean oil (the mass of monoglyceride accounts for 4 wt% of the mass of the oil phase).

[0103] Embodiment 21

[0104] Example 21: A method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining trisodium glycyrrhizinate and monoglyceride is the same as the preparation method of Comparative Example 2, except that in step (2), 0.4 g of monoglyceride is added to 4.6 g of soybean oil (the mass of monoglyceride accounts for 8 wt% of the mass of the oil phase).

[0105] Embodiment 22

[0106] Example 22: A method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining trisodium glycyrrhizinate and monoglyceride is the same as the preparation method of Comparative Example 2, except that in step (2), 0.8 g of monoglyceride is added to 4.2 g of soybean oil (the mass of monoglyceride accounts for 16 wt% of the mass of the oil phase).

[0107] Figure 5ais the frequency scanning diagram of the emulsion gel obtained when the mass percentage concentration of monoglyceride (the mass of monoglyceride accounts for the mass of the oil phase) is 0wt%, 1wt%, 2wt%, 4wt%, 8wt%, and 16wt%, respectively. Figure 5a It can be seen that the elastic modulus (G′) of all samples is significantly higher than the viscous modulus (G″), indicating that the emulsion gel exhibits solid-like properties. With the increase of the mass percentage concentration of monoglyceride, the elastic modulus and viscous modulus of the sample increased significantly, and the yield stress value increased. When the mass percentage concentration of monoglyceride increased from 0wt% to 16wt%, the elastic modulus increased from 10000Pa to 160000Pa, indicating that the sample has strong mechanical properties. The emulsion gel shows a low frequency dependence, and the loss factor value (G″ / G′) of all samples is low. This data also confirms that the emulsion gel has a strong gel strength. No yield stress point (G′=G″) appears at a higher frequency, indicating that the emulsion gel does not undergo a gel-sol transition under high-rate deformation. Therefore, the mechanical properties of glycyrrhizic acid-monoglyceride emulsion gel can be regulated by changing the monoglyceride concentration.

[0108] Figure 5b is a graph showing the change in modulus of the emulsion gel prepared when the mass percentage concentration of monoglyceride (the mass of monoglyceride accounts for the mass of the oil phase) is 4wt% during the heating and cooling cycles. Figure 5b It can be seen that the samples all show thermal response behavior. When the latex gel is heated to 80°C, a gel-sol transition occurs, and the elastic modulus and viscous modulus decrease. When it is cooled to 25°C, the latex gel reversibly gels, indicating that the reversible transition between the gel and sol states of the latex gel can be achieved by changing the temperature of the system. The latex gel has good temperature sensitivity, a large response temperature range, and highly controllable behavior, which can further expand the application range of the latex gel.

[0109] Comparative Example 3

[0110] (1) Mix 0.4g ammonium glycyrrhizinate powder and 0.005g vitamin B 12 (0.1 wt%) was uniformly dispersed in 4.595 g of deionized water, and stirred at 300 rpm for 5 min under heating at 80° C. in a water bath to obtain an 8 wt% ammonium glycyrrhizinate solution.

[0111] (2) 0.005 g of β-carotene (0.1 wt%) was added to 4.995 g of soybean oil and stirred in a constant temperature water bath at 80° C. for 10 min to obtain an oil phase (the mass of monoglyceride accounted for 0 wt % of the mass of the oil phase).

[0112] (3) 5 g of ammonium glycyrrhizic acid solution and 5 g of oil phase were mixed to obtain a mixed system (the mass of the oil phase accounted for 50 wt% of the mass of the mixed system), heated at 80° C. for 10 min, homogenized at 20,000 rpm while hot for 2 min, and then cooled in an ice bath at 4° C. for 10 min to obtain a thermosensitive structured emulsion gel prepared from ammonium glycyrrhizic acid. Vitamin B12 was measured on days 1, 3, 5, 7, and 15. 12 and β-carotene content to evaluate the protection ability of the system for hydrophilic and hydrophobic bioactive substances.

[0113] Embodiment 23

[0114] Example 23: A method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining ammonium glycyrrhizinate and monoglyceride, except that in step (2), 0.05g of monoglyceride and 0.005g of β-carotene (0.1wt%) are added to 4.945g of soybean oil (the mass of monoglyceride accounts for 1wt% of the mass of the oil phase), and the rest is the same as the preparation method of Comparative Example 3.

[0115] Embodiment 24

[0116] Example 24 is a method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining ammonium glycyrrhizinate and monoglyceride, except that in step (2), 0.1g monoglyceride and 0.005g β-carotene (0.1wt%) are added to 4.895g soybean oil (the mass of monoglyceride accounts for 2wt% of the mass of the oil phase), and the rest is the same as the preparation method of Comparative Example 3.

[0117] Embodiment 25

[0118] Example 25 is a method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining ammonium glycyrrhizinate and monoglyceride, except that in step (2), 0.2g monoglyceride and 0.005g β-carotene (0.1wt%) are added to 4.795g soybean oil (the mass of monoglyceride accounts for 4wt% of the mass of the oil phase), and the rest is the same as the preparation method of Comparative Example 3.

[0119] Embodiment 26

[0120] Example 26: A method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining ammonium glycyrrhizinate and monoglyceride is the same as the preparation method of Comparative Example 3, except that in step (2), 0.4 g of monoglyceride and 0.005 g of β-carotene (0.1 wt%) are added to 4.595 g of soybean oil (the mass of monoglyceride accounts for 8 wt% of the mass of the oil phase).

[0121] Embodiment 27

[0122] Example 27: A method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining ammonium glycyrrhizinate and monoglyceride, the same as the preparation method of Comparative Example 3, except that in step (2), 0.8 g of monoglyceride and 0.005 g of β-carotene (0.1 wt%) are added to 4.195 g of soybean oil (the mass of monoglyceride accounts for 16 wt% of the mass of the oil phase).

[0123] Another important application of emulsion gel is as a delivery system for active ingredients in food, medicine and cosmetics. Therefore, water-soluble vitamin B 12 and oil-soluble β-carotene were dissolved in the two phases respectively, and a functional emulsion gel of ammonium glycyrrhizinate-monoglyceride mixed system was further constructed to explore the loading and release capacity of the system for hydrophilic and hydrophobic bioactive substances. 12 and β-carotene can be uniformly loaded into the prepared emulsion gel, and vitamin B 12 The addition of β-carotene and β-carotene did not affect the formation of the emulsion gel, indicating that the emulsion gel has the potential use of loading active substances.

[0124] Figure 6a and Figure 6b Vitamin B12 encapsulated in the monoglyceride mass percentage concentration (the mass of monoglyceride accounts for the mass of the oil phase) of 0wt%, 1wt%, 2wt%, 4wt%, 8wt% and 16wt% in the emulsion gel during storage at room temperature (25°C) 12 and β-carotene retention rate diagram, given by Figure 6a and 6b It can be seen that at all monoglyceride mass percentage concentrations, vitamin B 12 After 15 days of storage, it was still retained in the emulsion gel system. Similarly, as the mass percentage concentration of monoglyceride increased from 0wt% to 8wt%, the retention rate of β-carotene in the emulsion gel increased from 70% to 85%, which shows that ammonium glycyrrhizinate-monoglyceride emulsion gel has the potential to protect and transport hydrophilic and hydrophobic active substances.

[0125] Comparative Example 4

[0126] (1) 0.4 g of ammonium glycyrrhizinate powder was uniformly dispersed in 4.6 g of deionized water, and stirred at 300 rpm for 5 min under heating at 80° C. in a water bath to obtain a clear and transparent 8 wt % ammonium glycyrrhizinate solution.

[0127] (2) 0.005 g of limonene (0.1 wt%) was added to 4.995 g of sunflower oil and stirred in a constant temperature water bath at 80° C. for 5 min to obtain an oil phase (the mass of monoglyceride accounted for 0 wt % of the mass of the oil phase).

[0128] (3) 5 g of ammonium glycyrrhizic acid solution and 5 g of oil phase were mixed to obtain a mixed system (the mass of the oil phase accounted for 50 wt% of the mass of the mixed system), which was heated at 80° C. for 10 min, homogenized at 20,000 rpm while hot for 2 min, and then cooled in an ice bath at 4° C. for 10 min to obtain a thermosensitive structured emulsion gel prepared from ammonium glycyrrhizic acid. The release of limonene from the emulsion gel at 50° C. every 8 min was measured by gas chromatography, and the release percentage of limonene at different time points was calculated to evaluate the potential of the emulsion gel as a flavor release system.

[0129] Embodiment 28

[0130] Example 28 is a method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining ammonium glycyrrhizinate and monoglyceride, except that in step (2), 0.05g of monoglyceride and 0.005g of limonene (0.1wt%) are added to 4.945g of sunflower seed oil (the mass of monoglyceride accounts for 1wt% of the mass of the oil phase), and the rest is the same as the preparation method of Comparative Example 4.

[0131] Embodiment 29

[0132] Example 29: A method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining ammonium glycyrrhizinate and monoglyceride is the same as the preparation method of Comparative Example 4, except that in step (2), 0.1 g of monoglyceride and 0.005 g of limonene (0.1 wt%) are added to 4.895 g of sunflower seed oil (the mass of monoglyceride accounts for 2 wt% of the mass of the oil phase).

[0133] Embodiment 30

[0134] Example 30 is a method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining ammonium glycyrrhizinate and monoglyceride, except that in step (2), 0.2g monoglyceride and 0.005g limonene (0.1wt%) are added to 4.795g sunflower seed oil (the mass of monoglyceride accounts for 4wt% of the mass of the oil phase), and the rest is the same as the preparation method of Comparative Example 4.

[0135] Embodiment 31

[0136] Example 31 is a method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining ammonium glycyrrhizinate and monoglyceride, except that in step (2), 0.4g monoglyceride and 0.005g limonene (0.1wt%) are added to 4.595g sunflower seed oil (the mass of monoglyceride accounts for 8wt% of the mass of the oil phase), and the rest is the same as the preparation method of Comparative Example 4.

[0137] Embodiment 32

[0138] Example 32 is a method for preparing a thermosensitive two-phase structured emulsion gel prepared by combining ammonium glycyrrhizinate and monoglyceride, except that in step (2), 0.8g monoglyceride and 0.005g limonene (0.1wt%) are added to 4.195g sunflower seed oil (the mass of monoglyceride accounts for 16wt% of the mass of the oil phase), and the rest is the same as the preparation method of Comparative Example 4.

[0139] Figure 7 The dynamic release curves of limonene in the emulsion gel prepared at the mass percentage concentration of monoglyceride (the mass of monoglyceride accounts for the mass of the oil phase) of 0wt%, 1wt%, 2wt%, 4wt%, 8wt% and 16wt% are shown in FIG. Figure 7 It can be seen that for all samples, a rapid limonene release rate was shown within the first 32 minutes, followed by a slower release rate. As the mass percentage concentration of monoglyceride increased, the release rate of limonene slowed down, indicating that ammonium glycyrrhizinate-monoglyceride emulsion gel has the potential to become a new aroma delivery system for improving food flavor perception, and its flavor release rate can be well controlled by simply changing the mass percentage concentration of monoglyceride. Therefore, the emulsion gel can be used as an excellent flavor delivery carrier and plastic fat substitute in future food processing, cosmetics, and medicine, such as artificial meat.

[0140] The implementation methods of the present invention are not limited to the above-mentioned embodiments, and any other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principles of the present invention shall be equivalent replacement methods and shall be included in the protection of the present invention.

Claims

1. A method for preparing a thermosensitive two-phase structured emulsion gel, characterized in that: The following steps are involved: 1) uniformly dispersing glycyrrhizic acid or a glycyrrhizic acid derivative in water, heating and stirring to obtain a glycyrrhizic acid solution or a glycyrrhizic acid derivative solution; the concentration of the glycyrrhizic acid solution or the glycyrrhizic acid derivative solution is 1wt%-8wt%; 2) adding a lipophilic gelling agent into liquid oil, heating and stirring, to obtain a uniformly dispersed oil phase; the lipophilic gelling agent is phytosterol and oryzanol; the mass of the lipophilic gelling agent accounts for 1wt%-30wt% of the mass of the oil phase; 3) mixing the glycyrrhizic acid solution or glycyrrhizic acid derivative solution obtained in step 1) with the oil phase obtained in step 2) to obtain a mixed system, heating the mixed system until it is completely dissolved, homogenizing it while hot, and then cooling it to obtain a temperature-sensitive two-phase structured emulsion gel; the mass of the oil phase accounts for 10wt%-80wt% of the mass of the mixed system.

2. The preparation method according to claim 1, characterized in that: In step 1), the glycyrrhizic acid derivative includes one of ammonium glycyrrhizinate, monopotassium glycyrrhizinate, dipotassium glycyrrhizinate and trisodium glycyrrhizinate.

3. The preparation method according to claim 1, characterized in that: In step 1), the temperature of the heating and stirring is 60-95° C., and the time of the heating and stirring is 5-30 min.

4. The preparation method according to claim 1, characterized in that: Step 2) The liquid oil includes one or more of sunflower oil, soybean oil, rapeseed oil, corn oil, olive oil, peanut oil, camellia oil, fish oil, algae oil, and linseed oil.

5. The preparation method according to claim 1, characterized in that: In step 2), the heating and stirring temperature is 60-95° C., and the heating and stirring time is 5-30 min.

6. The preparation method according to claim 1, characterized in that: In step 3), the heating temperature is 60-95° C., and the heating time is 5-30 min.

7. The preparation method according to claim 1, characterized in that: In step 3), the homogenizing speed is 5000-30000 rpm, and the homogenizing time is 1-5 min; the cooling temperature is 0-25° C., and the cooling time is 10-30 min.

8. The temperature-sensitive two-phase structured emulsion gel prepared by the preparation method according to any one of claims 1 to 7.

9. Use of the temperature-sensitive dual-phase structured emulsion gel according to claim 8 in food, cosmetics or medicine.

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