CN106561971A - Rice protein peptide and preparation method thereof - Google Patents

Abstract

The invention provides rice protein peptide and a preparation method thereof and belongs to the technical field of rice protein deep processing. Waste obtained in a starch sugar production process and an enzymic preparation which is cheap and easy to obtain are utilized to produce the high-purity rice protein peptide through a compound enzyme method. The preparation method includes the following steps of superfine grinding of rice residues, impurity removal, enzymolysis, decoloration, concentration and drying, and a packaged finished product is obtained. The rice protein peptide and the preparation method thereof have the advantages that through one-step enzymolysis of trypsin, neutral protease and flavor proteinase at normal pressure, the high-purity rice protein peptide is prepared; raw materials are rich in source, and the equipment cost is low; the rice protein peptide is easy to absorb, resistant to fatigue and high in nutrition value; degreasing, soluble sugar removal, insoluble starch and cellulose removal and washing are integrated, and the rice protein peptide is suitable for enzymolysis and separation with residues. Concentration equipment combines processes of concentration, defoaming and cleaning to avoid forming of nitrate; through a fully-enzymatic method process, the salt content in a product is reduced; and enzyme consumption is small, the material-liquid ratio is large, the process is simplified, and conditions are mild.

Description

A kind of rice protein peptide and preparation method thereof

technical field

The invention relates to the technical field of food deep processing.

Background technique

Rice dregs is a by-product obtained after high-temperature enzymatic hydrolysis of rice starch. The protein has undergone certain denaturation, and the secondary structure has been destroyed. Moreover, the content of glutenin in the rice dregs protein is relatively high, which directly leads to a decrease in the solubility of the protein, and the extraction of the protein is also difficult. more difficult. At present, rice dregs protein is mainly used as animal feed. Due to its poor digestibility and high protein content, animals will directly excrete most of the undigested protein after eating, resulting in a large waste of protein resources. Very severe nitrogen pollution aggravated. Based on the above analysis, the rational development and application of rice dregs protein is imperative.

Peptides obtained by enzymatic method, the molecular weight is easy to control, the product is rich in green and environmental protection properties, the molecular weight is small (mostly 1000-5000D), these small molecular peptides can be directly absorbed without digestion, and have the functions of carrier, transportation, transmitter and nutrition. Extremely active and diverse important biological functions. The single enzyme modification method has limited modification degree or unsatisfactory modification effect, and compound enzyme modification has become the research focus in the field of protein.

Chinese patent document CN103918869A (application number 201410169464.5) discloses a method for preparing high-purity rice protein peptides by secondary enzymatic hydrolysis with α-amylase and complex protease at room temperature.

Chinese patent document CN1559256A (application number 200410006119.6) proposes a method for preparing rice protein peptides by α-amylase and neutral protease, which has high nutritional value and does not contain cholesterol, which is beneficial to the cardiovascular and cerebrovascular health of the human body and has good safety.

It can be seen from the above public documents that most of them use a single enzyme for enzymolysis, the enzymolysis effect is poor, and the protein peptide content is low. Its functional properties can be further improved, and its application in the food industry can be improved.

Contents of the invention

The purpose of the present invention is to provide a rice protein peptide and a preparation method thereof for the deficiencies in the prior art, and use rice dregs to prepare high-purity rice protein peptide in one step through a compound enzyme method.

The present invention is realized through the following technical solutions.

The rice protein peptide of the present invention is characterized in that the total protein content is 88.45-90.34%, the protein peptide purity is 85.65%, the solubility is 99.32%, and 90% of the peptide molecular weight is less than 5000 Dalton.

A method for preparing rice protein peptides according to the present invention uses trypsin, neutral protease and flavor protease to enzymatically hydrolyze rice protein, which is characterized by comprising the following steps.

(1) Grinding: Put the raw rice dregs into a superfine pulverizer for pulverization, and use cold water to protect the nutrients in the powder during the processing.

(2) Impurity removal: Dilute the crushed rice dregs with water to an appropriate concentration, heat to 45°C-50°C, add 200,000 U/g of cellulase and stir at a constant temperature for enzymolysis, and the enzymolysis time is 1 hour. The amount of rice dregs is 0.1-0.2kg/ton. Heat up to 95°C to inactivate the enzyme for 15 minutes, add 80,000 U/g of α-amylase, stir at 90°C-95°C for enzymolysis, the enzymolysis time is 0.5h, and the amount of α-amylase is 0.2-0.3kg / ton of rice dregs, washed several times with water to obtain washed rice dregs.

(3) Enzymolysis: Dilute the washed rice dregs with water to an appropriate concentration, heat to 50°C-55°C, adjust the pH value to 6.8-7.0 with a certain mass concentration of sodium hydroxide and hydrochloric acid solution, and the proportion of rice dregs is 1% : 2.5%: 1% respectively add trypsin, neutral protease, flavor protease constant temperature stirring enzymolysis 4-5h, its described trypsin, neutral protease, flavor protease enzymatic activity is respectively 4000U/g, 200,000 U/g , 100,000 U/g, after the reaction was completed, the temperature was raised to 95°C to inactivate the enzyme for 15 minutes to obtain the crude rice dregs protein peptide liquid.

(4) Decolorization: The prepared coarse rice dregs protein peptide liquid is decolorized with activated carbon, the decolorization of the activated carbon is at 55°C for 0.5h, the pH value is 5.5-6.5, and the added amount is 1.5%- 2.5%.

(5) Concentration: The thick rice dregs protein peptide liquid is vacuum concentrated under certain conditions until the solid content is above 70%.

(6) Drying: The concentrated rice dregs protein peptide solution is spray-dried at an inlet air temperature of 180°C-190°C and an outlet air temperature of 80°C-85°C to obtain a packaged product.

The advantages of the present invention are that high-purity rice protein peptides are prepared by step enzymolysis with trypsin, flavor protease and neutral protease under normal pressure, the source of raw materials is abundant, and the cost of equipment is low; it is easy to absorb, anti-fatigue, and has high nutritional value; It integrates soluble sugar removal, insoluble starch removal, cellulose removal, and washing together, and is suitable for enzymatic hydrolysis and slag separation. Concentration equipment: combine the process of concentration, defoaming and cleaning to avoid the formation of nitrate. The whole enzymatic process reduces the salt content in the product; the dosage of enzyme is small, the ratio of solid to liquid is large, the process is simplified and the conditions are mild.

detailed description

Example 1.

The preparation method of the above-mentioned high-purity rice protein peptide comprises the following steps.

(1) Pulverization: Weigh 500kg of rice dregs and add them to a superfine pulverizer for pulverization. During the processing, cold water is used to protect the nutrients in the powder.

(2) Impurity removal: In a 5000L reaction tank, add 5000L of water, add 500kg of crushed rice dregs, stir and mix, raise the temperature to 50°C, add 0.1kg of cellulase, and stir for 1 hour at constant temperature. Raise the temperature to 95°C to kill the enzyme for 15 minutes, add 0.15 kg of α-amylase, stir and react at a constant temperature for 0.5 hours, wash with water several times to obtain water-washed rice dregs.

(3) Enzymolysis: Add 2500L water to the washed rice dregs, heat to 50°C, adjust the pH value to 6.8 with a certain mass concentration of sodium hydroxide and hydrochloric acid solution, and add trypsin, neutral protease and flavor protease in proportion 5kg, 12.5kg and 5kg were stirred at constant temperature for 4 hours for enzymolysis, and after the reaction was completed, the temperature was raised to 95°C to inactivate the enzyme for 15 minutes to obtain the crude rice dregs protein peptide solution.

(4) Decolorization: The prepared coarse rice dregs protein peptide liquid was decolorized with activated carbon. The decolorization of activated carbon was carried out at 55°C for 0.5h, the pH value was 5.5, and the addition amount was 4kg.

(5) Concentration: The thick rice dregs protein peptide liquid is vacuum concentrated under certain conditions until the solid content is above 70%.

(6) Drying: The concentrated rice dregs protein peptide liquid is dried and dehydrated using spray drying equipment at an inlet air temperature of 180°C and an outlet air temperature of 80°C to obtain the high-purity rice protein peptide product.

Example 2.

The preparation method of the above-mentioned high-purity rice protein peptide comprises the following steps.

(1) Pulverization: Weigh 400kg of rice dregs and add them to a superfine pulverizer for pulverization. During the processing, cold water is used to protect the nutrients in the powder.

(2) Impurity removal: In a 5000L reaction tank, add 4000L of water, add 400kg of crushed rice dregs, stir and mix, raise the temperature to 50°C, add 0.1kg of cellulase, and stir for 1 hour at constant temperature. Raise the temperature to 95°C to kill the enzyme for 15 minutes, add 0.15 kg of α-amylase, stir and react at a constant temperature for 0.5 hours, wash with water several times to obtain water-washed rice dregs.

(3) Enzymolysis: add 2000L water to the washed rice dregs, heat to 50°C, adjust the pH value to 6.8 with a certain mass concentration of sodium hydroxide and hydrochloric acid solution, and add trypsin, neutral protease and flavor protease in proportion 4kg, 10kg and 4kg were stirred at constant temperature for 4 hours for enzymatic hydrolysis. After the reaction, the temperature was raised to 95°C to inactivate the enzyme for 15 minutes to obtain the crude rice dregs protein peptide solution.

(4) Decolorization: The prepared coarse rice dregs protein peptide solution was decolorized with activated carbon. The decolorization of activated carbon was carried out at 55°C for 0.5h, the pH value was 5.5, and the addition amount was 3.2kg.

(5) Concentration: The thick rice dregs protein peptide liquid is vacuum concentrated under certain conditions until the solid content is above 70%.

(6) Drying: The concentrated rice dregs protein peptide liquid is dried and dehydrated using spray drying equipment at an inlet air temperature of 180°C and an outlet air temperature of 80°C to obtain the high-purity rice protein peptide product.

Example 3.

The preparation method of the above-mentioned high-purity rice protein peptide comprises the following steps.

(1) Pulverization: Weigh 460kg of rice dregs and add them to a superfine pulverizer for pulverization. During the processing, cold water is used to protect the nutrients in the powder.

(2) Impurity removal: In a 5000L reaction tank, add 4600L of water, add 460kg of crushed rice dregs, stir and mix, raise the temperature to 50°C, add 0.1kg of cellulase and stir for 1 hour at constant temperature. Raise the temperature to 95°C to kill the enzyme for 15 minutes, add 0.15 kg of α-amylase, stir and react at a constant temperature for 0.5 hours, wash with water several times to obtain water-washed rice dregs.

(3) Enzymolysis: add 2300L water to the washed rice dregs, heat to 50°C, adjust the pH value to 6.8 with a certain mass concentration of sodium hydroxide and hydrochloric acid solution, and add trypsin, neutral protease and flavor protease in proportion 4.6kg, 11.5kg and 4.6kg were stirred at constant temperature for 4 hours, and after the reaction, the temperature was raised to 95°C to inactivate the enzyme for 15 minutes to obtain the crude rice dregs protein peptide solution.

(4) Decolorization: The prepared coarse rice dregs protein peptide liquid was decolorized with activated carbon. The decolorization of activated carbon was carried out at 55°C for 0.5h, the pH value was 5.5, and the addition amount was 3.7kg.

(5) Concentration: The thick rice dregs protein peptide liquid is vacuum concentrated under certain conditions until the solid content is above 70%.

(6) Drying: The concentrated rice dregs protein peptide liquid is dried and dehydrated using spray drying equipment at an inlet air temperature of 180°C and an outlet air temperature of 80°C to obtain the high-purity rice protein peptide product.

Table 1 Molecular weight distribution of rice protein peptides MW (Da) rice protein peptide >10000 5.60 5000-10000 1.84 3000-5,000 3.27 1,000-3000 18.36 120-1,000 52.24 <120 18.68

Claims (2)

1. A rice protein peptide, characterized in that its total protein content is 88.45-90.34%, the protein peptide purity is 85.65%, solubility is 99.32%, and 90% of the peptide molecular weight＜5000 Daltons. 2. the preparation method of a kind of rice protein peptide as claimed in claim 1 is characterized in that comprising the following steps: (1) Grinding: Put the raw rice dregs into the ultrafine pulverizer for crushing, and use cold water to protect the nutrients in the powder during the processing; (2) Impurity removal: Dilute the crushed rice dregs with water to an appropriate concentration, heat to 45°C-50°C, add 200,000 U/g of cellulase and stir at a constant temperature for enzymolysis, and the enzymolysis time is 1 hour. The amount is 0.1-0.2kg/ton of rice dregs; the temperature is raised to 95°C to inactivate the enzyme for 15 minutes, 80,000 U/g of α-amylase is added, and the enzymolysis is carried out at 90°C-95°C with constant temperature stirring, and the enzymolysis time is 0.5h. The amount of the α-amylase is 0.2-0.3kg/ton of rice dregs, washed several times to obtain washed rice dregs; (3) Enzymolysis: Dilute the washed rice dregs with water to an appropriate concentration, heat to 50°C-55°C, adjust the pH value to 6.8-7.0, add trypsin, Neutral protease, flavor protease constant temperature stirring enzymolysis 4-5h, its described trypsin, neutral protease, flavor protease enzymatic activity is respectively 4000U/g, 200,000 U/g, 100,000 U/g, after the reaction, Raise the temperature to 95°C to inactivate the enzyme for 15 minutes to obtain the crude rice dregs protein peptide liquid; (4) Decolorization: The prepared coarse rice dregs protein peptide liquid is decolorized with activated carbon, the decolorization of the activated carbon is at 55°C for 0.5h, the pH value is 5.5-6.5, and the added amount is 1.5%- 2.5%; (5) Concentration: the thick rice dregs protein peptide liquid is vacuum concentrated under certain conditions until the solid content is above 70%; (6) Drying: The concentrated rice dregs protein peptide solution is spray-dried at an inlet air temperature of 180°C-190°C and an outlet air temperature of 80°C-85°C.