Method for preparing double-nutrition fat substitute based on soybean protein-silibinin compound high internal phase emulsion

Abstract

The invention discloses a method for preparing a double-nutrition fat substitute based on soybean protein-silibinin compound high internal phase emulsion, and belongs to the technical field of food processing. The method comprises the following steps: respectively preparing a soybean protein solution and a silybin solution to form a soybean protein-silybin compound, dissolving resveratrol into an oil phase by virtue of an ultrasonic dispersion means, and homogenizing at a high speed to prepare a soybean protein-silybin compound high internal phase emulsion as the double-nutrition fat substitute. The milk is green, healthy, low in cost and environment-friendly, and caters to the consumption requirements of vegetarians, people with specific diet requirements and people complying with religious diet restrictions, and the addition of the silibinin improves the antioxidant activity and stabilizes the emulsion interface, and endows the emulsion with antibacterial performance. Meanwhile, the resveratrol carried by the emulsion enables the fat substitute to have potential health benefits and nutritional value. The method for preparing the double-nutrition fat substitute which is similar to real fat in texture and healthy by packaging natural polyphenol through the soybean protein-silibinin high-internal-phase emulsion provides a wider development thought for application of the high-internal-phase emulsion; and the method is beneficial exploration of using the emulsion based on the vegetable protein as an effective substitute of saturated fat in various foods.

Description

Technical Field

[0001] The invention belongs to the technical field of food processing, and in particular relates to a method for preparing a dual-nutrition fat substitute based on a soybean protein-silybin complex high internal phase emulsion. Background Art

[0002] In traditional whole meat and seafood products, adipose tissue is a key component that determines taste, flavor and texture. Natural adipose tissue is composed of fat cells with a diameter of tens of microns. Its hydrophobic core is rich in triglycerides and lipophilic components, and the outer layer is wrapped by a cell wall composed of phospholipids and proteins. Terrestrial animal fats represented by cattle, sheep and pigs are semi-solid at low temperatures and melt when heated above body temperature. This characteristic is due to the high proportion of long-chain saturated fatty acids (such as palmitic acid and stearic acid) in their triglycerides, which have a high melting point. However, excessive intake of saturated fat is closely related to metabolic diseases such as coronary heart disease and atherosclerosis, prompting the food science community to seek solutions to replace animal fat with plant-based healthy lipids. In this context, high internal phase emulsions based on soy protein have become an ideal candidate system for fat substitutes due to their unique structural and functional properties.

[0003] Oil-in-water high internal phase emulsions achieve close packing of droplets to form a semi-solid network structure by increasing the volume fraction of the dispersed phase to a critical value (>74%). This geometric arrangement between droplets is highly similar to the three-dimensional stacking of natural fat. In high internal phase emulsion gels, oil phase droplets are forced to deform into polyhedral forms due to their high volume share and are separated only by a continuous aqueous phase membrane of nanometer thickness, which is significantly comparable to the topological structure of fat cells separated by cell walls and matrix proteins. More importantly, the droplet interface of high internal phase emulsions can be precisely controlled by protein-polyphenol complexes to form a stable interfacial membrane similar to the cell wall, giving it rheological properties similar to animal adipose tissue (such as shear thinning and temperature-responsive melting).

[0004] The problem of high saturated fatty acids in traditional animal fats can be completely solved in high internal phase emulsions by selecting monounsaturated (such as olive oil) or polyunsaturated lipids (such as linseed oil). The core advantage of soy protein as an interfacial stabilizer lies in its complete protein properties - its amino acid composition covers 9 essential amino acids for the human body, and the proportion meets the FAO / WHO standards, which is significantly better than other plant proteins (such as pea protein lacks sulfur-containing amino acids). In addition, the introduction of silybin, a natural polyphenol, not only enhances interfacial stability through covalent / non-covalent effects, but also gives the emulsion multiple biological activities: its antioxidant ability can inhibit lipid peroxidation and extend the shelf life of the product; its antibacterial and anti-biofilm properties can reduce the risk of microbial contamination during processing and storage, which is completely absent in traditional animal fats. Resveratrol (Res) carried at the same time is a natural polyphenol substance that is found in various plant sources such as grapes, red wine, peanuts and berries. It is well-known for its potential health benefits (including antioxidant, anti-inflammatory, anti-aging, anti-obesity, anti-diabetes, anti-tumor and various other properties), which has aroused special interest. Summary of the invention

[0005] The purpose of the present invention is to provide a method for preparing a dual-nutrition fat substitute based on a soybean protein-silybin complex high internal phase emulsion.

[0006] A method for preparing a dual-nutrition fat substitute based on a soy protein-silybin complex high internal phase emulsion, the method comprising dissolving soy protein powder and silybin in deionized water and anhydrous ethanol respectively, mixing them evenly to form a soy protein-silybin complex, and simultaneously dissolving resveratrol in an oil phase by means of ultrasonic dispersion to prepare a high internal phase emulsion system loaded with resveratrol.

[0007] It is further defined that the soy protein solution has a concentration of 2-4% (w / v).

[0008] It is further defined that the concentration of the silybin solution is 0-2.4% (w / v).

[0009] It is further defined that the ratio between the two is 19:1 (v / v), and the stirring time is 2 h.

[0010] It is further defined that the resveratrol is dissolved in soybean oil by ultrasound-assisted dispersion (200 W, 30 s) to a total concentration of 0-1% (w / v).

[0011] It is further defined that after the soy protein-silybin complex solution is mixed with the oil phase, the volume fraction of the oil phase is 74-80% (v / v), and a high-speed homogenizer is used to homogenize at 10000-30000 r / min for 1-5 min at room temperature.

[0012] The invention provides a high internal phase emulsion containing resveratrol and a soybean protein-silybin complex obtained by the method.

[0013] The invention provides application of a high internal phase emulsion containing a soybean protein-silybin complex and carrying resveratrol in fat substitutes.

[0014] Beneficial effects: The present invention constructs a complex system by non-covalently binding soy protein and silybin, and after sufficient reaction, a high internal phase emulsion is prepared as a nutritious, healthy, and texture-similar fat substitute. The present invention is not only green and healthy, low-cost, and environmentally friendly, and caters to the consumption needs of vegetarians, people with specific dietary needs, and people who abide by religious dietary restrictions, but also the addition of silybin improves the antioxidant activity and stabilizes the emulsion interface, and gives the emulsion antibacterial properties. At the same time, the resveratrol carried by the emulsion gives the fat substitute potential health benefits and nutritional value. The method of using soy protein-silybin high internal phase emulsion to encapsulate natural polyphenols to prepare a dual-nutritional fat substitute with a texture similar to real fat and health provides a wider range of development ideas for the application of high internal phase emulsions, and is also a beneficial exploration of plant protein-based emulsions as effective substitutes for saturated fat in various foods. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 For the flow chart.

[0016] Figure 2 Changes in the appearance of freshly prepared emulsions for the different treatment group complexes.

[0017] Figure 3 Changes in rheological properties of composite emulsions in different treatment groups.

[0018] Figure 4 The storage stability of the complex emulsion in different treatment groups. Specific embodiments Example

[0019] Reference Figure 1Soy protein (protein content of 91.83%) was collected from defatted soybean meal by alkali dissolution and acid precipitation. The protein extract was dialyzed and freeze-dried and then stored at 4°C. Soy protein powder was dissolved in deionized water (2%, w / v). Silybin was dissolved in anhydrous ethanol to different concentrations as working stock solution and stirred for 2 h to dissolve fully. An equal volume of blank ethanol solution was added to silymarin and stirred for at least 2 h in an anaerobic environment. The ratio between the two was 19:1 (v / v). The mixture was mixed evenly and the ethanol was removed by rotary evaporation at 45°C. The pH value of the aqueous phase was adjusted to 7.0 at room temperature. Resveratrol was dissolved in soybean oil with soybean oil as the oil phase. Ultrasonic dispersion (200 W, 30 s) was used to make the total concentration 0.5% (w / v) and the oil phase volume 75% (v / v). IKA homogenizer was used for high-speed homogenization (10000 r / min, 1 min). The obtained high internal phase emulsion can be used as a fat substitute. Example

[0020] Reference Figure 1 Soy protein (protein content of 91.83%) was collected from defatted soybean meal by alkali dissolution and acid precipitation. The protein extract was dialyzed and freeze-dried and then stored at 4°C. Soy protein powder was dissolved in deionized water (2%, w / v). Silybin was dissolved in anhydrous ethanol to different concentrations as working stock solution and stirred for 2 h to dissolve fully. The above silybin working solution was added dropwise to the above soybean protein solution at a ratio of 19:1 (v / v) to make the final concentration of silybin reach 0.03% (w / v). The mixture was stirred for at least 2 h in an anaerobic environment to mix well. The ethanol was removed by rotary evaporation at 45°C. The pH value of the aqueous phase was adjusted to 7.0 at room temperature. Resveratrol was dissolved in soybean oil with soybean oil as the oil phase. The total concentration was 0.5% (w / v) and the oil phase volume was 75% (v / v) by ultrasound-assisted dispersion (200 W, 30 s). The mixture was homogenized at high speed using an IKA homogenizer (10000 r / min, 1 min), the obtained high internal phase emulsion can be used as a fat substitute. Example

[0021] Reference Figure 1Soy protein (protein content of 91.83%) was collected from defatted soybean meal by alkali dissolution and acid precipitation. The protein extract was dialyzed and freeze-dried and then stored at 4°C. Soy protein powder was dissolved in deionized water (2%, w / v). Silybin was dissolved in anhydrous ethanol to different concentrations as working stock solution and stirred for 2 h to dissolve fully. The above silybin working solution was added dropwise to the above soybean protein solution at a ratio of 19:1 (v / v) to make the final concentration of silybin reach 0.06% (w / v). The mixture was stirred for at least 2 h in an anaerobic environment to mix well. The ethanol was removed by rotary evaporation at 45°C. The pH value of the aqueous phase was adjusted to 7.0 at room temperature. Resveratrol was dissolved in soybean oil with soybean oil as the oil phase. The total concentration was 0.5% (w / v) and the oil phase volume was 75% (v / v) by ultrasound-assisted dispersion (200 W, 30 s). The mixture was homogenized at high speed using an IKA homogenizer (10000 r / min, 1 min), the obtained high internal phase emulsion can be used as a fat substitute. Example

[0022] Reference Figure 1 Soy protein (protein content of 91.83%) was collected from defatted soybean meal by alkali dissolution and acid precipitation. The protein extract was dialyzed and freeze-dried and then stored at 4°C. Soy protein powder was dissolved in deionized water (2%, w / v). Silybin was dissolved in anhydrous ethanol to different concentrations as working stock solution and stirred for 2 h to dissolve fully. The above silybin working solution was added dropwise to the above soybean protein solution at a ratio of 19:1 (v / v) to make the final concentration of silybin reach 0.09% (w / v). The mixture was stirred for at least 2 h in an anaerobic environment to mix well. The ethanol was removed by rotary evaporation at 45°C. The pH value of the aqueous phase was adjusted to 7.0 at room temperature. Resveratrol was dissolved in soybean oil with soybean oil as the oil phase. The total concentration was 0.5% (w / v) and the oil phase volume was 75% (v / v) by ultrasound-assisted dispersion (200 W, 30 s). The mixture was homogenized at high speed using an IKA homogenizer (10000 r / min, 1 min), the obtained high internal phase emulsion can be used as a fat substitute. Example

[0023] Reference Figure 1Soy protein (protein content of 91.83%) was collected from defatted soybean meal by alkali dissolution and acid precipitation. The protein extract was dialyzed and freeze-dried and then stored at 4°C. Soy protein powder was dissolved in deionized water (2%, w / v). Silybin was dissolved in anhydrous ethanol to different concentrations as working stock solution and stirred for 2 h to dissolve fully. The above silybin working solution was added dropwise to the above soybean protein solution at a ratio of 19:1 (v / v) to make the final concentration of silybin reach 0.12% (w / v). The mixture was stirred for at least 2 h in an anaerobic environment to mix well. The ethanol was removed by rotary evaporation at 45°C. The pH value of the aqueous phase was adjusted to 7.0 at room temperature. Resveratrol was dissolved in soybean oil with soybean oil as the oil phase. The total concentration was 0.5% (w / v) and the oil phase volume was 75% (v / v) by ultrasound-assisted dispersion (200 W, 30 s). The mixture was homogenized at high speed using an IKA homogenizer (10000 r / min, 1 min), the obtained high internal phase emulsion can be used as a fat substitute.

[0024] The following tests are used to verify the test results: 1. Place fresh emulsions (15 mL) after different treatments in 20 mL sample bottles and take pictures of the sample appearance in bright light.

[0025] Depend on Figure 2 It can be seen that the composites treated differently all formed a uniform, stable, fine and smooth high internal phase emulsion state.

[0026] 2. Determine the storage modulus (G') and loss modulus (G'') of the sample. Before the dynamic oscillation experiment, first obtain the linear viscoelastic region (LVR) of the sample by dynamic strain scanning. Then set a constant strain of 0.1% (within the LVR) and an oscillation frequency scanning range of 0.1-100 Hz.

[0027] Depend on Figure 3 It can be seen that when the silybin content is 0.06% (w / v), the addition of polyphenols promotes the adsorption of protein at the oil-water interface, and the emulsion droplets formed by the complex are smaller, resulting in better emulsion elasticity.

[0028] 3. The fresh emulsions (15 mL) after different treatments were placed in 20 mL sample bottles. The storage stability of the emulsions was analyzed by measuring the change in whey particle size after 48 days of storage at room temperature. The particle size of the emulsions was determined by dynamic light scattering technology. In order to avoid multiple scattering effects, the obtained emulsions were diluted 100 times with deionized water, and then the emulsion particle size was measured using a Malvern particle size analyzer.

[0029] Depend on Figure 4 It can be seen that when the silybin content is 0.06% (w / v), the storage stability of the emulsion is better.

Claims

1. A method for preparing a dual-nutrition fat substitute based on a soybean protein-silybin complex high internal phase emulsion, characterized in that: The method comprises: (1) dissolving soy protein powder and silybin in water and ethanol respectively; (2) stirring to obtain a soy protein-silybin complex; (3) dissolving resveratrol into the oil phase by ultrasound assistance; and (4) high-speed homogenization to prepare a high internal phase emulsion of the soy protein-silybin complex carrying resveratrol.

2. The method according to claim 1, characterized in that The concentration of the soy protein solution is 2%-4% (w / v).

3. The method according to claim 1, characterized in that The concentration of the silybin solution is 0-2.4% (w / v).

4. The method according to claim 1, characterized in that The ratio between the two was 19:1 (v / v), and the stirring time was 2 h.

5. The method according to claim 1, characterized in that Resveratrol was dissolved in soybean oil and dispersed by ultrasound (200 W, 30 s) to a total concentration of 0-1% (w / v).

6. The method according to claim 1, characterized in that After the soy protein-silybin complex solution is mixed with the oil phase, the volume fraction of the oil phase is 74-80%, and a high-speed homogenizer is used to homogenize at room temperature at 10000-30000 r / min for 1-5 minutes.

7. A high internal phase emulsion containing resveratrol and a soy protein-silybin complex obtained by the method according to any one of claims 1 to 6.

8. Use of the high internal phase emulsion containing resveratrol and the soy protein-silybin complex as claimed in claim 7 in fat substitutes.

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