CN108003219A - A kind of can improve cracks rice protein extracting ratio and carries out the method for glycosylation modification to it - Google Patents

Abstract

The invention discloses a method capable of improving the extraction rate of broken rice protein and carrying out glycosylation modification on it. Firstly, the broken rice flour is treated with suitable ultra-high pressure combined with heat treatment, which can significantly increase the albumin, globulin, The extraction rate of gliadin and glutenin reduces the content of the ordered structure of glutenin to make it easier to dissolve, which is beneficial to the subsequent extraction of rice protein; then the broken rice is extracted in an alkaline solution, and the broken rice protein in an alkaline solution It has good solubility in medium, and the use of ultrasonic-assisted extraction of broken rice protein has the advantages of short time, low temperature, and low energy consumption. At the same time, the broken rice protein obtained also has good functional properties; Under the action of ultrasound, the solubility of the glycosylated modified protein is significantly improved, the emulsification activity is enhanced and the emulsification stability is enhanced, the hydrophobic groups are exposed, the surface hydrophobicity of the original protein molecule is enhanced, and it can be used as a food additive, etc., which is more conducive to Human body absorbs.

Description

A method capable of improving the extraction rate of broken rice protein and carrying out glycosylation modification

technical field

The invention relates to the technical field of rice deep processing, in particular to a method capable of improving the extraction rate of broken rice protein and performing glycosylation modification on it.

Background technique

For a long time, my country's rice processing has been in a state of only satisfying rations, and the valuable by-products such as 40 million tons of rice husks, more than 30 million tons of broken rice, and more than 14 million tons of rice bran produced by rice processing have not yet been well developed. use. At present, the conversion and deep processing of a large number of rice in our country is an urgent task. The implementation of high-efficiency value-added and full-utilization industrialization of rice deep processing can transform my country from a large rice-producing country to a powerful rice-producing country, and from low-efficiency agriculture to high-efficiency agriculture. Broken rice is a by-product of rice milling, and its nutritional value is basically the same as that of whole rice, but its utilization rate is only 30% of that of whole rice. Rice protein is an immunogenic protein and is a good source of protein for infants and people with allergies. Rice protein is popular because of its complete ratio of essential amino acids, high utilization rate and easy digestion and absorption by the human body. Therefore, extracting these rice proteins with high nutritional value from broken rice has good economic benefits and application value.

In the prior art, the broken rice is often further crushed into rice flour to extract the rice protein. The extraction process is complicated and the extraction rate is low. In order to improve the extraction rate of the rice protein, it is necessary to carry out corresponding modification before the extraction of the broken rice. , so as to improve the subsequent efficiency of rice protein. However, broken rice protein is mainly an alkali-soluble protein, with high surface hydrophobicity and many disulfide bonds, and low solubility at neutral pH, which affects its functional properties and application in production. Water-insoluble glutenin accounts for about 80% of rice protein, so it is of great significance to study the modification of broken rice protein to improve solubility. Lactose is one of the important nutrients for growth and development. It can promote intellectual development and can promote the growth of intestinal lactic acid bacteria, which is beneficial to intestinal health. Lactose can promote the absorption of calcium in the process of calcium metabolism. After combining with low-sensitivity rice protein, it strengthens the functional properties of rice protein, making it easier to be absorbed by the body and maximize the nutritional value. Therefore, it is necessary to extract more rice Proteins are glycosylated and modified to meet people's health needs, thereby increasing the value of the industry.

Contents of the invention

The purpose of the present invention is to provide a method capable of improving the extraction rate of broken rice protein and carrying out glycosylation modification in order to make up for the defects of the prior art.

The present invention is achieved through the following technical solutions:

A method capable of improving the extraction rate of broken rice protein and carrying out glycosylation modification thereof, comprising the following specific steps:

(1) After removing impurities, crush the broken rice with a pulverizer, pass through a 100-mesh sieve, and make rice flour. Add an appropriate amount of deionized water to the prepared rice flour and mix evenly. After stirring and mixing, add it to a polyethylene bag to vacuum Seal, package the sample into the pressure chamber of high-pressure equipment, heat it at high pressure for 15-20 minutes, and then depressurize to normal pressure at a pressure relief speed of 100MPa/s;

(2) Quickly dehydrate the rice flour taken out from the high-pressure equipment with 8-10 times the volume of 95% ethanol, filter it with suction, then infiltrate it with anhydrous ethanol equal to the volume of rice, mix it evenly and then filter it with suction to obtain the rice flour Dried at 40-45°C, crushed, passed through a 100-mesh sieve, sealed in a ziplock bag and placed in a desiccator for later use;

(3) Add an appropriate amount of deionized water to the rice flour processed in step (2) to adjust the ratio of liquid to material, adjust the pH to 9.5-10 with 10wt% sodium hydroxide solution, control the temperature at 60-65°C, and extract by ultrasonic 30-40 minutes, then centrifuge at a speed of 3500-400 rpm for 20-25 minutes, take the supernatant, add an appropriate amount of hydrochloric acid with a concentration of 10wt% to adjust the pH to 4.2-4.5, and continue at 3500-400 rpm Centrifuge at a high speed for 20-25 minutes, take the precipitate, wash 2-3 times with deionized water, and then freeze-dry to obtain broken rice protein;

(4) Mix broken rice protein and lactose in a certain proportion, dissolve in an appropriate amount of 0.1mol/L phosphate buffer, control the rice protein concentration to 12-16mg/mL, stir magnetically at room temperature for 60-90 minutes, add rice Sodium azide with 0.5% protein content, preheat the mixture to 90-100°C and place it in an ultrasonic device for a period of time. After the reaction is completed, immediately put it in an ice bath to cool down to end the reaction, and then dialyze for 20-24 hours. Finally, the obtained liquid can be freeze-dried.

The method for improving the extraction rate of broken rice protein and modifying it by glycosylation includes adding an appropriate amount of deionized water and mixing in step (1), and the specific amount of water added is 50%.

The method for improving the extraction rate of broken rice protein and performing glycosylation modification on it, the high-pressure and high-heat treatment described in step (1), the specific conditions are: boost the pressure at a boosting speed of 50MPa/s To 600MPa, the temperature is maintained at 45°C.

In the method for improving the extraction rate of broken rice protein and performing glycosylation modification, the liquid-to-material ratio is adjusted in step (3), and the specific liquid-to-material ratio is 1:12.

The method for improving the extraction rate of broken rice protein and carrying out glycosylation modification, the ultrasonic wave described in step (3), the specific power of the ultrasonic wave is 120W.

The method for improving the extraction rate of broken rice protein and modifying it by glycosylation, the mixing of broken rice protein and lactose in a certain ratio in step (4) refers to the ratio of 55:45 mix.

The method for improving the extraction rate of broken rice protein and performing glycosylation modification on it is described in step (4) in the ultrasonic device for a period of time, and the specific conditions refer to the ultrasonic power of 300W and the ultrasonic time of 30 minute.

The advantages of the present invention are: firstly, the present invention adopts suitable ultra-high pressure combined with heat treatment to process the broken rice flour, which can effectively improve the solubility and gel expansion rate of the broken rice flour, and can significantly increase the albumin in rice under the action of ultra-high pressure combined with heat treatment. , globulin, prolamin and glutenin extraction rate, reducing the content of glutenin ordered structure makes it easier to dissolve, which is beneficial to the subsequent extraction of rice protein; then the broken rice is extracted in alkaline solution, the broken rice protein It has good solubility in alkaline solution, and the use of ultrasonic-assisted extraction of broken rice protein has the advantages of short time, low temperature, and low energy consumption. At the same time, the broken rice protein obtained also has good functional properties; Modification, under the action of ultrasonic waves, the solubility of protein modified by glycosylation is significantly improved, the emulsification activity is improved and the emulsification stability is enhanced, the hydrophobic group is exposed, and the surface hydrophobicity of the original protein molecule is enhanced, which can be used as a food additive Etc., which is more conducive to human body absorption.

Detailed ways

A method capable of improving the extraction rate of broken rice protein and carrying out glycosylation modification thereof, comprising the following specific steps:

(1) After removing impurities, crush the broken rice with a pulverizer, pass through a 100-mesh sieve, and make rice flour. Add 50% deionized water to the prepared rice flour and mix evenly. Stir and mix and add it to a polyethylene bag. Vacuum-sealed, the packaged sample is placed in the pressure chamber of the high-pressure equipment, and the pressure is increased to 600MPa at a boosting speed of 50MPa/s, the temperature is maintained at 45°C, and the high-pressure heat treatment is performed for 15 minutes, and then depressurized at a decompression speed of 100MPa/s. pressure to normal pressure;

(2) Quickly dehydrate the rice flour taken out from the high-pressure equipment with 8 times the volume of 95% ethanol, filter it with suction, then infiltrate it with anhydrous ethanol equal to the volume of the rice, mix it evenly and filter it with suction, and the obtained rice flour is at 40 Crush it after blow drying at ℃, pass through a 100-mesh sieve, pack it in a ziplock bag and put it in a desiccator for later use;

(3) Add an appropriate amount of deionized water to the rice flour processed in step (2) to adjust the ratio of liquid to material to 1:12, adjust the pH to 9.5 with 10wt% sodium hydroxide solution, control the temperature at 60°C, and use 120W Ultrasonic extraction with high power for 30 minutes, then centrifuged at 3500 rpm for 20 minutes, took the supernatant, added an appropriate amount of hydrochloric acid with a concentration of 10wt% to adjust the pH to 4.2, and continued to centrifuge at 3500 rpm for 20 minutes , take the precipitate, wash it twice with deionized water, and then freeze-dry to obtain broken rice protein;

(4) Mix broken rice protein and lactose at a ratio of 55:45, dissolve in an appropriate amount of 0.1mol/L phosphate buffer, control the rice protein concentration to 12mg/mL, stir magnetically for 60 minutes at room temperature, add rice protein mass 0.5% sodium azide, preheat the mixture to 90°C and place it in an ultrasonic device, control the ultrasonic power to 300W, and the ultrasonic time is 30 minutes. Immediately after the reaction is completed, put it in an ice bath to cool down to end the reaction, and then dialyze for 20 hours , and finally freeze-dry the obtained liquid.

Claims (7)

1. A method that can improve the extraction rate of broken rice protein and carry out glycosylation modification to it, is characterized in that, comprises the following concrete steps: (1) After removing impurities, crush the broken rice with a pulverizer, pass through a 100-mesh sieve, and make rice flour. Add an appropriate amount of deionized water to the prepared rice flour and mix evenly. After stirring and mixing, add it to a polyethylene bag to vacuum Seal, package the sample into the pressure chamber of high-pressure equipment, heat it at high pressure for 15-20 minutes, and then depressurize to normal pressure at a pressure relief speed of 100MPa/s; (2) Quickly dehydrate the rice flour taken out from the high-pressure equipment with 8-10 times the volume of 95% ethanol, filter it with suction, then infiltrate it with anhydrous ethanol equal to the volume of rice, mix it evenly and then filter it with suction to obtain the rice flour Dried at 40-45°C, crushed, passed through a 100-mesh sieve, sealed in a ziplock bag and placed in a desiccator for later use; (3) Add an appropriate amount of deionized water to the rice flour processed in step (2) to adjust the ratio of liquid to material, adjust the pH to 9.5-10 with 10wt% sodium hydroxide solution, control the temperature at 60-65°C, and extract by ultrasonic 30-40 minutes, then centrifuge at a speed of 3500-400 rpm for 20-25 minutes, take the supernatant, add an appropriate amount of hydrochloric acid with a concentration of 10wt% to adjust the pH to 4.2-4.5, and continue at 3500-400 rpm Centrifuge at a high speed for 20-25 minutes, take the precipitate, wash 2-3 times with deionized water, and then freeze-dry to obtain broken rice protein; (4) Mix broken rice protein and lactose in a certain proportion, dissolve in an appropriate amount of 0.1mol/L phosphate buffer, control the rice protein concentration to 12-16mg/mL, stir magnetically at room temperature for 60-90 minutes, add rice Sodium azide with 0.5% protein content, preheat the mixture to 90-100°C and place it in an ultrasonic device for a period of time. After the reaction is completed, immediately put it in an ice bath to cool down to end the reaction, and then dialyze for 20-24 hours. Finally, the obtained liquid can be freeze-dried. 2. A method capable of improving the extraction rate of broken rice protein and carrying out glycosylation modification according to claim 1, characterized in that, adding an appropriate amount of deionized water to mix in step (1), The specific amount of water added is 50%. 3. A method capable of improving the extraction rate of broken rice protein and modifying it by glycosylation according to claim 1, characterized in that, the high-pressure and high-heat treatment described in step (1), the specific conditions are: Boost the pressure to 600MPa at a boosting speed of 50MPa/s, and maintain the temperature at 45°C. 4. A method capable of improving the extraction rate of broken rice protein and carrying out glycosylation modification according to claim 1, characterized in that, in step (3), the liquid-to-material ratio is adjusted, and the specific liquid The material ratio is 1:12. 5. A method capable of improving the extraction rate of broken rice protein and carrying out glycosylation modification thereof according to claim 1, characterized in that, for the ultrasonic wave described in step (3), the specific ultrasonic power is 120W. 6. A method capable of increasing the extraction rate of broken rice protein and carrying out glycosylation modification thereof according to claim 1, characterized in that the broken rice protein and lactose described in step (4) Proportional mixing means mixing in a ratio of 55:45. 7. A method capable of improving the extraction rate of broken rice protein and carrying out glycosylation modification according to claim 1, characterized in that, the ultrasonic device described in step (4) is treated for a period of time, specifically The conditions refer to ultrasonic power of 300W and ultrasonic time of 30 minutes.