High-emulsibility peanut protein powder and preparation method thereof

Abstract

The invention provides high-emulsibility peanut protein powder and a preparation method thereof, and belongs to the field of peanut protein powder product development. The preparation method comprises the following steps: (1) dissolving cold-pressed peanut meal in a phosphate buffer solution according to a solid-liquid ratio of 1: 10 to prepare a cold-pressed peanut meal solution with the concentration of 10%; (2) performing ultrasonic treatment on the cold-pressed peanut meal solution, and controlling the ultrasonic time to be 10-60 minutes, the temperature to be 5-45 DEG C, the power density to be 1.33-6.67 W / cm < 3 > and the duty ratio to be 50%; (3) freeze-drying the cold-pressed peanut meal solution subjected to ultrasonic treatment to obtain high-emulsibility peanut protein powder; and (4) the product is added into flour, the addition amount is controlled to be 3%-5%, the characteristics of flour quality, stretching, gelatinization and the like of dough are not changed, and the nutrition of the dough is enhanced. According to the preparation method, ultrasonic treatment is adopted, the process is simple, the cost is low, green and pollution-free effects are achieved, the reaction process is easy to control, and the prepared peanut protein powder is good in emulsibility and has great significance in improving the nutrition and processing quality of flour food, expanding the application range of the peanut protein powder in food processing and the like.

Description

[0001] Technical Field The present invention relates to the field of peanut protein powder product development, and more particularly to a highly emulsifiable peanut protein powder and a preparation method thereof. Background Art : Cold-pressed peanut meal has high nutritional value, with a protein content of about 45% to 50% and an essential amino acid content of 10.85%. It contains eight essential amino acids for the human body and has a high digestibility. It is comparable to the nutritional value of animal protein and has dual advantages in price and nutrition. Compared with rapeseed protein, peanut protein has fewer toxic substances and is a safe, high-nutrition protein. Therefore, cold-pressed peanut meal is a protein base with great development potential. However, due to their poor emulsification and other functional properties, they often cannot meet the needs of industrial production, which limits their application.

[0003] With the continuous deepening of scientific research, enzymatic modification, heat treatment modification, ultrasonic modification, etc. are the most commonly used protein modification technologies, among which ultrasonic modification is the most ideal one. The principle of ultrasonic modification is that after the buffer solution and the cold-pressed peanut meal are mixed, the protein liquid is subjected to high-intensity ultrasonic waves, which produces mechanical and directional effects, leading to an increase in temperature and pressure, thereby gradually increasing mass transfer and heat transfer between materials, accelerating the denaturation of proteins, and modifying peanut protein by changing its physical and chemical properties, which provides the possibility of improving and enriching its functional characteristics and biological activity and solving its limitations. After the cold-pressed peanut meal is treated with ultrasonic waves, the peanut protein molecules produce polarization under the induction of a uniform ultrasonic field, destroying the non-covalent bonds (hydrophobic interactions, disulfide bonds, and electrostatic interactions) that maintain the spatial structure of the protein, partially unfolding the protein molecules, increasing the flexibility of the molecules, and more protein molecules are bound to the oil-water interface. At the same time, the hydrophobic residues inside the peanut protein molecules are exposed on the surface of the peanut protein, and the hydrophobicity of the surface of the peanut protein is enhanced, so the emulsifying activity of the peanut protein is enhanced.

[0004] The emulsifying ability of peanut protein can enhance the elasticity, toughness and gas holding capacity of dough in flour products, so as to improve the fermentation ability and improve the taste of food. In addition, peanut protein can interact with amylose to delay and prevent food aging, prevent starch retrogradation and strengthen gluten strength. Therefore, the present invention uses ultrasonically modified cold-pressed peanut meal to prepare highly emulsifiable peanut protein powder, in order to provide new methods and products in the field of plant protein.

[0005] Summary of the invention The present invention provides a highly emulsifiable peanut protein powder and a preparation method thereof. The reaction process of the present invention proceeds spontaneously, the raw material cold-pressed peanut meal does not need any pretreatment, and does not need to add any chemical reagents. The present invention is a method for preparing highly emulsifiable peanut protein powder with a simple principle, rapidity, easy operation, controllability, and no pollution.

[0006] To achieve the above object, the present invention adopts the following technical solution: The first aspect of the present invention is to provide a high-emulsification peanut protein powder and a preparation method thereof, which comprises: Step 1: Dissolve the cold-pressed peanut meal in a phosphate buffer solution at a solid-liquid ratio of 1:10 to prepare a cold-pressed peanut meal solution with a concentration of 10%.

[0007] Step 2: Place the ultrasonic probe deep into the cold-pressed peanut meal solution, control the ultrasonic time to 10-60 min, the temperature to 5-45°C, and the ultrasonic power density to 1.33-6.67 W / cm 3 , duty cycle 50%.

[0008] Step 3: After the reaction is completed, the cold-pressed peanut meal solution after ultrasonic treatment is taken out and freeze-dried for 48 hours to obtain a sample. The peanut protein powder with a solubility range of 51.90% to 62.00%, an emulsification activity range of 21.04 mL / g to 33.76 mL / g, and an emulsification stability range of 29.83 min to 83.24 min is obtained.

[0009] Step 4: Add the product to the flour, controlling the amount added at 3%~5%, without changing the flour quality, stretchability, gelatinization and other properties of the dough, and enhancing the nutrition of the dough.

[0010] Preferably, the ultrasonic treatment time in step 2 is 30 to 50 min.

[0011] Preferably, the ultrasonic treatment temperature in step 2 is controlled by a circulating water bath at a temperature of 25-45°C.

[0012] Preferably, the ultrasonic power in step 2 is 400-600 W.

[0013] The second aspect of the present invention is to provide a peanut protein powder and a preparation method thereof, which is prepared by the above-mentioned modification method and has the following additional technical features: According to an embodiment of the present invention, the solubility range of the prepared peanut protein powder is 51.90% to 62.00%; According to an embodiment of the present invention, the prepared peanut protein powder has an emulsification activity range of 21.04 mL / g to 33.76 mL / g, and an emulsification stability range of 29.83 min to 83.24 min; According to an embodiment of the present invention, the amount added to the dough ranges from 3% to 5%.

[0014] The present invention adopts the above technical solution to have the following advantages: (1) The present invention adopts ultrasonic modification to prepare highly emulsifiable peanut protein powder, and its process principle is simple, rapid, easy to operate, controllable and pollution-free.

[0015] (2) The peanut protein powder prepared by the present invention has high emulsification properties, thereby achieving further high-value utilization of cold-pressed peanut meal. DETAILED DESCRIPTION

[0016] The specific implementation modes of the invention are described in detail below, but it should be understood that the protection scope of the present invention is not limited by the specific implementation modes.

[0017] Example 1 Take 7 g of undefatted cold-pressed peanut meal, add 70 mL of 0.01 mol / L phosphate buffer solution, stir magnetically for 1 h to fully dissolve it, then transfer it all into an ultrasonic cup, and insert the ultrasonic probe 5 cm below the liquid surface so that it is in the middle of the solution. Connect it to an intelligent constant temperature bath and use a circulating water bath to control the temperature. Treat it at an ultrasonic power of 200 W for 50 min, set the temperature to 35°C, and set the duty cycle to 50%. After the reaction is completed, take it out and freeze-dry it for 48 h to obtain highly emulsifiable peanut protein powder, and measure the emulsification properties.

[0018] Compared with the raw material cold-pressed peanut meal, the high-emulsifying peanut protein powder prepared in this embodiment has an emulsifying activity improved by 60.46% and an emulsifying stability improved by 68.66%.

[0019] Example 2 Take 7 g of undefatted cold-pressed peanut meal, add 70 mL of 0.01 mol / L phosphate buffer solution, stir magnetically for 1 h to fully dissolve it, then transfer it all into an ultrasonic cup, and insert the ultrasonic probe 5 cm below the liquid surface so that it is in the middle of the solution. Connect it to an intelligent constant temperature bath and use a circulating water bath to control the temperature. Treat it at an ultrasonic power of 200 W for 40 min, set the temperature to 35°C, and set the duty cycle to 50%. After the reaction is completed, take it out and freeze-dry it for 48 h to obtain the modified cold-pressed peanut meal high-emulsifying peanut protein powder, and measure the emulsification properties.

[0020] Compared with the raw material cold-pressed peanut meal, the high-emulsifying peanut protein powder prepared in this embodiment has an emulsifying activity improved by 38.74% and an emulsifying stability improved by 125.9%.

[0021] Example 3 Take 7 g of undefatted cold-pressed peanut meal, add 70 mL of 0.01 mol / L phosphate buffer solution, stir magnetically for 1 h to fully dissolve it, then transfer it all into an ultrasonic cup, and insert the ultrasonic probe 5 cm below the liquid surface so that it is in the middle of the solution. Connect it to an intelligent constant temperature bath and use a circulating water bath to control the temperature. Treat it at an ultrasonic power of 500 W for 40 min, set the temperature to 35°C, and set the duty cycle to 50%. After the reaction is completed, take it out and freeze-dry it for 48 h to obtain highly emulsifiable peanut protein powder, and measure the emulsification properties.

[0022] Compared with the raw material cold-pressed peanut meal, the high-emulsifying peanut protein powder prepared in this embodiment has an emulsifying activity improved by 34.84% and an emulsifying stability improved by 48.54%.

[0023] Example 4 Take 7 g of undefatted cold-pressed peanut meal, add 70 mL of 0.01 mol / L phosphate buffer solution, stir magnetically for 1 h to fully dissolve it, then transfer it all into an ultrasonic cup, and insert the ultrasonic probe 5 cm below the liquid surface so that it is in the middle of the solution. Connect it to an intelligent constant temperature bath and use a circulating water bath to control the temperature. Treat it at an ultrasonic power of 200 W for 40 min, set the temperature to 35°C, and set the duty cycle to 50%. After the reaction is completed, take it out and freeze-dry it for 48 h to obtain highly emulsifiable peanut protein powder, and measure the emulsification properties.

[0024] Compared with the raw material cold-pressed peanut meal, the high-emulsifying peanut protein powder prepared in this embodiment has an emulsifying activity improved by 53.33% and an emulsifying stability improved by 101.6%.

[0025] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Anyone familiar with this technology can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the definition of the claims.

Claims

1. A highly emulsifiable peanut protein powder and a preparation method thereof, characterized in that The following steps are involved: (1) Dissolving cold-pressed peanut meal in a phosphate buffer solution at a solid-liquid ratio of 1:10 to prepare a cold-pressed peanut meal solution with a concentration of 10%; (2) The cold-pressed peanut meal solution was ultrasonically treated with an ultrasonic time of 10-60 min, a temperature of 5-45 °C, and a power density of 1.33-6.67 W / cm 3 , duty cycle 50%; (3) The cold-pressed peanut meal solution after ultrasonic treatment was freeze-dried to obtain peanut protein powder with a solubility range of 51.90%-62.00%, an emulsification activity range of 21.04 mL / g-33.76 mL / g, and an emulsification stability range of 29.83 min-83.24 min; (4) Add this product to flour, controlling the addition amount to 3%~5%, without changing the flour quality, stretchability, gelatinization and other properties of the dough, and enhancing the nutrition of the dough.

2. A highly emulsifiable peanut protein powder and a preparation method thereof according to claim 1, characterized in that: The concentration of the cold-pressed peanut meal in step (1) is 10%.

3. A highly emulsifiable peanut protein powder and a preparation method thereof according to claim 1, characterized in that: The ultrasonic treatment time in step (2) is 30 to 50 min.

4. A highly emulsifiable peanut protein powder and a preparation method thereof according to claim 1, characterized in that: The ultrasonic treatment temperature in step (2) is controlled by a circulating water bath at a temperature of 25-45°C.

5. A highly emulsifiable peanut protein powder and a preparation method thereof according to claim 1, characterized in that: The ultrasonic power density in step (2) is 5.33~6.67 W / cm 3 .

6. A highly emulsifiable peanut protein powder and a preparation method thereof according to claim 1, characterized in that: In step (3), peanut protein powder with a solubility range of 51.90% to 62.00%, an emulsification activity range of 21.04 mL / g to 33.76 mL / g, and an emulsification stability range of 29.83 min to 83.24 min is obtained.

7. A highly emulsifiable peanut protein powder and a preparation method thereof according to claim 1, characterized in that: In step (4), the amount of the additive in the flour is controlled to be 3% to 5%, without changing the flour quality, stretchability, gelatinization and other properties of the dough, and enhancing the nutrition of the dough.

8. A highly emulsifiable peanut protein powder prepared by the method according to any one of claims 1 to 7.