Method for preparing nano starch lipid composite emulsifier at normal temperature

Abstract

The invention relates to a method for preparing a nano starch lipid composite emulsifier at normal temperature, which is characterized in that on the basis of diversified starch raw materials and different types of lipids, efficient preparation of a nano-scale compound is realized through a normal-temperature acoustic resonance treatment technology. The method breaks through the limitation of traditional high-temperature preparation, adopts a chemical method and an enzymolysis method to prepare nano starch particles under a normal-temperature condition, and then combines the starch particles with lipid by utilizing an acoustic resonance technology to form a stable nano-scale compound. The process is simplified, green, efficient and multifunctional, and the process is simpler; the normal-temperature acoustic resonance technology is adopted, so that the energy consumption is reduced, and the production efficiency is improved; the prepared nano-composite has potential application of emulsifiers and fat substitutes, can meet the requirements of modern consumers for healthy diet, and widens the application range of the nano-composite in the food industry.

Description

Technical Field

[0001] The invention belongs to the technical field of food processing, and in particular relates to a method for preparing a nano starch lipid composite emulsifier at room temperature. Background Art

[0002] Starch is a common polysaccharide in higher plants and the main storage form of plant carbohydrates. It accounts for a large proportion of the human diet. It not only provides the energy necessary for human survival, but also has physiological functions such as regulating human sugar metabolism, lipid metabolism, and intestinal microbial diversity.

[0003] The preparation of starch particles at the nanoscale can be achieved by chemical and enzyme catalysis methods. The so-called nano starch particles (Starch Nanoparticles, SNPs) refer to starch molecules dispersed into tiny structures with at least one dimension reaching the nanoscale size. Nano starch particles have shown application potential in many fields such as food, medicine, cosmetics and environmental science due to their unique physical and chemical properties, such as high specific surface area, improved solubility and adjustable crystallinity, as well as good biocompatibility and biodegradability.

[0004] Lipids are commonly found in food, and in food formulation design, lipids are often added to improve the taste and quality of the final product. Lipids are important components of organisms. They play a key role in a variety of biological functions. Lipids are an efficient storage form of energy and one of the main components of cell membranes, helping to maintain the structure and function of cells. Certain lipids such as phospholipids and cholesterol are involved in intercellular signaling. These functions make lipids indispensable in organisms.

[0005] An emulsifier is a substance that helps two immiscible liquids (usually oil and water) mix together. The emulsification principle of traditional emulsifiers is mainly based on their molecular structure. They usually have two parts with different properties: a hydrophilic part (water-soluble) and a hydrophobic part (oil-soluble). This structure enables the emulsifier to work at the oil-water interface, thereby reducing the surface tension between oil and water and helping the two immiscible liquids mix. This mechanism of action based on molecular amphiphilicity is the basis for traditional emulsifiers to achieve emulsification and stabilization of emulsions.

[0006] Nano starch lipid complex is a new type of emulsifier, which replaces the traditional emulsifier in the form of solid particles. Compared with traditional emulsifiers, particles can be quickly adsorbed to the oil-water interface due to their higher interfacial energy, greatly reducing the oil-water interfacial tension and forming a dense physical barrier on the interface. Therefore, it can inhibit the aggregation of the dispersed phase of the emulsion. At the same time, the emulsion-based delivery carrier has the effects of improving the water solubility, stability, delayed release, and increasing bioavailability of bioactive substances. Nano starch lipid complex has the advantages of environmental friendliness and superior stability. Therefore, it plays an important role in the development of functional foods.

[0007] The preparation methods of starch lipid complexes can be divided into chemical methods (dimethyl sulfoxide dispersion method and alkaline solution method), physical methods (hydrothermal method, rapid viscosity analyzer gelatinization method, differential scanning calorimeter method, jet cooking method, extrusion cooking method, high pressure treatment method, etc.) and enzymatic methods (complete enzymatic hydrolysis method: starch phosphorylase catalysis method; partial enzymatic hydrolysis method: α-amylase, β-amylase, etc.). The above treatment methods have the disadvantages of complex process, waste liquid generated during the preparation process may pollute the environment and low production efficiency, and their application is subject to certain restrictions. Summary of the invention

[0008] In order to overcome the deficiencies of the above-mentioned prior art, the purpose of the present invention is to provide a method for preparing a nano starch lipid composite emulsifier at room temperature. In view of the diverse nutritional needs of different consumers, this technology is not only safe and efficient, but also has low energy consumption, and can meet the urgent market demand for emulsifiers and fat substitutes. In addition, by using nano starch as a carrier of lipids, the stability of lipids can be significantly improved while ensuring the supply of fatty acids. By using room temperature acoustic resonance technology, the limitations of traditional high temperature preparation have been broken through, and a complex with emulsifying properties and fat replacement function can be efficiently prepared at room temperature. The present invention can not only replace the use of traditional emulsifiers in food processing, but also provide strong technical support for the development of new healthy foods. This complex shows huge market potential and diverse application prospects.

[0009] In order to achieve the above object, the technical solution adopted by the present invention is: A method for preparing a nano starch lipid composite emulsifier at room temperature, characterized in that it comprises the following steps: (1) Prepare a 1.0-10.0 mol / L CaCl2 solution, let it stand to clarify, and add starch to the solution to prepare a 1%-20% starch milk; (2) placing the starch emulsion in (1) into an acoustic resonance container and treating it until the transparent zone (i.e., the gelatinized portion) around the particle reaches a certain size (e.g., the size of the transparent zone is approximately 10% to 70% of the entire particle); (3) adding ice water to the starch paste prepared in step (2) to terminate gelatinization, stirring and standing to separate water and starch, discarding the supernatant, and washing the obtained precipitate with ice water by centrifugation twice, and then adding ice water to the obtained precipitate; (4) freeze-drying the product in step (3), adding α-amylase diluted with water to a final concentration of 10-200 U / mL, and placing it in an acoustic resonance container for treatment to obtain nano starch particles; (5) Adding 10% to 50% of the dry weight fraction of the nano starch particles in step (4) to the lipids, and mixing them in an acoustic resonance instrument; (6) After the complex reaction is completed, the sample is quickly cooled, and then freeze-dried, crushed and sieved to obtain the nano-starch lipid complex. The final product is sealed and stored at 4°C.

[0010] The concentration of CaCl2 in step (1) is 1.0-10.0 mol / L.

[0011] The adjustment parameters of the acoustic resonance in the steps (2) and (4) are 5-100 Hz, the acceleration is 5-100 g, and the processing time is 5-60 min.

[0012] The rotation speed of the centrifugal washing in step (3) is 500-8000 r / min, and the processing time is 1-20 min.

[0013] The α-amylase treatment time in step (4) is 2 to 20 hours.

[0014] The beneficial effects of the present invention are: 1. Multifunctionality and health attributes: The prepared nano starch lipid complex can not only be used as an efficient emulsifier in food processing, but also has the potential to replace traditional fats; this composite technology can significantly reduce the digestibility of starch in the product, providing low-sugar or low-GI food options for consumers with specific health needs. Due to its multifunctionality, the complex is not only suitable for traditional food processing, but also plays an important role in the development of new healthy foods, meeting the health and nutrition needs of modern consumers.

[0015] 2. Environmental sustainability: Through acoustic resonance technology, nano starch lipid complexes can be efficiently prepared at room temperature, avoiding the potential impact of high temperature treatment on the environment, and achieving green production. Starch is an abundant natural renewable resource on the earth. Its wide source and low cost provide a solid foundation for large-scale production. The raw materials and methods used in this technology meet the requirements of environmental sustainability.

[0016] 3. The second objective of the present invention is to develop a new type of emulsifier, which is intended to play an emulsifying and stabilizing role in the food industry. This emulsifier will help improve the texture and stability of food.

[0017] 4. The third goal is to create a fat substitute that can not only simulate the taste and flavor of fat, but also avoid the single taste problem caused by chemical flavors, providing a richer and more natural food experience.

[0018] 5. The fourth objective is to provide a method for preparing resistant starch, which can be used as a low glycemic index (GI) ingredient suitable for daily diet. Its application helps to enhance people's satiety and helps to reduce the incidence of obesity, satisfying modern people's pursuit of healthy diet.

[0019] 6. The present invention realizes efficient compounding of nano starch particles and lipids through acoustic resonance technology, thereby enhancing the stability and dispersibility of the product; and utilizes chemical methods and enzymatic methods to prepare nano starch particles at room temperature, thereby ensuring the functionality of starch.

[0020] 7. Application prospects of the present invention. Nano starch lipid complexes have multifunctionality and health properties, providing a solid technical foundation for the development of healthy foods, and have wide application potential in the fields of food, cosmetics, medicine, etc., especially in promoting the innovation of healthy and low-fat foods, with significant social benefits and market value. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a graph of average particle size of nano potato starch lipid emulsions prepared in Examples 1, 2 and 3; Figure 2 The droplet morphology of potato starch lipid composite emulsifier prepared under acoustic resonance treatment in Examples 1, 2 and 3, wherein A: oleic acid, B: linoleic acid, C: linolenic acid; Figure 3 is a graph of peroxide concentration of potato starch oleic acid composite emulsifier under acoustic resonance treatment prepared in Example 1; Figure 4 is a graph of peroxide concentration of potato starch linoleic acid composite emulsifier under acoustic resonance treatment prepared in Example 2; Figure 5 This is a graph of peroxide concentration of potato starch linolenic acid composite emulsifier under acoustic resonance treatment prepared in Example 3. DETAILED DESCRIPTION

[0022] In order to better understand the present invention, the content of the present invention is further explained below in conjunction with the embodiments, but the content of the present invention is not limited to the following embodiments. Example 1

[0023] Prepare a 4.0 mol / L CaCl2 solution, let it settle, and add potato starch to the solution to prepare a 5% starch milk. Place the starch milk in an acoustic resonance container and mix it at an acceleration of 75 g, a frequency of 62.5 Hz, and a treatment time of 25 min until the transparent ring around the particle (i.e., the gelatinized part) reaches a certain degree (the size of the transparent ring around the particle is about 30% of the entire particle). Add ice water to the starch paste to terminate gelatinization, stir and stand to separate the water and starch, discard the supernatant, and continue to centrifuge and wash the obtained precipitate twice with ice water, then add ice water to the obtained precipitate; freeze-dry the sample, add α-amylase diluted with water to a final concentration of 80 U / mL, and place it in an acoustic resonance container to obtain nano starch particles. Add oleic acid at a dry mass fraction of 10% to the nano starch particles, and mix them in an acoustic resonance instrument at an acceleration of 75 g, a frequency of 62.5 Hz, and a treatment time of 25 min. After the composite reaction is completed, the sample is quickly cooled, and then freeze-dried, crushed and sieved to obtain the nano-starch oleic acid complex. The final sample is sealed and stored at 4°C. Example 2

[0024] Prepare a 4.0 mol / L CaCl2 solution, let it settle, and add potato starch to the solution to prepare a 5% starch milk. Place the starch milk in an acoustic resonance container and mix it at an acceleration of 75 g, a frequency of 62.5 Hz, and a treatment time of 25 min until the transparent ring around the particle (i.e., the gelatinized part) reaches a certain degree (the size of the transparent ring around the particle is about 30% of the entire particle). Add ice water to the starch paste to terminate gelatinization, stir and stand to separate the water and starch, discard the supernatant, and continue to centrifuge and wash the obtained precipitate twice with ice water, then add ice water to the obtained precipitate; freeze-dry the sample, add α-amylase diluted with water to a final concentration of 80 U / mL, and place it in an acoustic resonance container to obtain nano starch particles. Add linoleic acid with a dry mass fraction of 10% to the nano starch particles, and mix them in an acoustic resonance instrument at an acceleration of 75 g, a frequency of 62.5 Hz, and a treatment time of 25 min. After the composite reaction is completed, the sample is quickly cooled, and then freeze-dried, crushed and sieved to obtain the nano-starch linoleic acid complex. The final sample is sealed and stored at 4°C. Example 3

[0025] Prepare a 4.0 mol / L CaCl2 solution, let it settle, and add potato starch to the solution to prepare a 5% starch milk. Place the starch milk in an acoustic resonance container and mix it at an acceleration of 75 g, a frequency of 62.5 Hz, and a treatment time of 25 min until the transparent ring around the particle (i.e., the gelatinized part) reaches a certain degree (the size of the transparent ring around the particle is about 30% of the entire particle). Add ice water to the starch paste to terminate gelatinization, stir and stand to separate the water and starch, discard the supernatant, and continue to centrifuge and wash the obtained precipitate twice with ice water, then add ice water to the obtained precipitate; freeze-dry the sample, add α-amylase diluted with water to a final concentration of 80 U / mL, and place it in an acoustic resonance container to obtain nano starch particles. Add 10% linolenic acid to the nano starch particles and mix them in an acoustic resonance instrument at an acceleration of 75 g, a frequency of 62.5 Hz, and a treatment time of 25 min. After the composite reaction is completed, the sample is quickly cooled, and then freeze-dried, crushed and sieved to obtain the nano-starch linolenic acid complex. The final sample is sealed and stored at 4°C.

Claims

1. A method for preparing a nano starch lipid composite emulsifier at room temperature, characterized in that: The following steps are involved: (1) Prepare a 1.0-10.0 mol / L CaCl2 solution, let it stand to clarify, and add starch to the solution to prepare a 1%-20% starch milk; (2) placing the starch emulsion in (1) into an acoustic resonance container and treating it until the transparent zone (i.e., the gelatinized portion) around the particle reaches a certain size (e.g., the size of the transparent zone is approximately 10% to 70% of the entire particle); (3) adding ice water to the starch paste prepared in step (2) to terminate gelatinization, stirring and standing to separate water and starch, discarding the supernatant, and washing the obtained precipitate with ice water by centrifugation twice, and then adding ice water to the obtained precipitate; (4) freeze-drying the product in step (3), adding α-amylase diluted with water to a final concentration of 10-200 U / mL, and placing it in an acoustic resonance container for treatment to obtain nano starch particles; (5) Adding 10% to 50% of the dry weight fraction of the nano starch particles in step (4) to the lipids, and mixing them in an acoustic resonance instrument; (6) After the complex reaction is completed, the sample is quickly cooled, and then freeze-dried, crushed and sieved to obtain the nano-starch lipid complex. The final product is sealed and stored at 4°C.

2. The method for preparing a nano starch lipid composite emulsifier at room temperature according to claim 1, characterized in that: The concentration of CaCl2 in step (1) is 1.0-10.0 mol / L.

3. The method for preparing a nano starch lipid composite emulsifier at room temperature according to claim 1, characterized in that: The adjustment parameters of the acoustic resonance in the steps (2) and (4) are 5-100 Hz, the acceleration is 5-100 g, and the processing time is 5-60 min.

4. The method for preparing a nano starch lipid composite emulsifier at room temperature according to claim 1, characterized in that: The rotation speed of the centrifugal washing in step (3) is 500-8000 r / min, and the processing time is 1-20 min.

5. The method for preparing a nano starch lipid composite emulsifier at room temperature according to claim 1, characterized in that: The α-amylase treatment time in step (4) is 2 to 20 hours.

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