CN116210768A - A kind of preparation method of oat milk with good stability - Google Patents

Abstract

The invention relates to a preparation method of oat milk with good stability. The method comprises the following steps: crushing oat to obtain oat flour; uniformly stirring oat flour and alpha-amylase, wherein the addition amount of the alpha-amylase is 0.05-0.5% of the mass of the oat flour, and forming a prefabricated mixture; reactive extrusion of the mixture in a twin screw extruder to obtain extruded oat flour; pulping oat flour, inactivating enzyme, performing ultrasonic dispersion, filtering, blending, homogenizing, sterilizing and filling to obtain the finished oat milk. The oat milk obtained by the method has good stability, does not need to add other stabilizing agents or thickening agents, does not need long-time enzymolysis, and saves cost; meanwhile, the sensory score is higher, and the taste requirement of consumers on the oat milk is met.

Description

A kind of preparation method of oat milk with good stability

technical field

The invention relates to the technical field of high-efficiency biotransformation of food processing, in particular to a preparation method of oat milk beverage.

Background technique

Oats are also called naked oats, oil wheat, jade wheat, wild wheat, brome, etc. It is an annual plant of the genus Oats in the Gramineae family, and is also one of the important sources of human food. Oatmeal is rich in starch, protein, fat, and dietary fiber, among which the content of β-glucan is significantly higher than that of other grains, which has the functions of lowering cholesterol, lowering blood fat, regulating blood sugar, and preventing cancer.

In recent years, plant-based dairy products represented by oat milk have become a trend to replace milk. Compared with milk and other plant milks, oat milk has unique nutritional value and advantages. Compared with milk, oat milk is rich in dietary fiber, especially β-glucan, which can help people reduce blood sugar and fat; oat milk does not contain lactose, which is very friendly to patients with lactose intolerance. , Compared with other plant milks such as soy milk, oats have the advantage of not containing soy allergens.

However, the preparation of oat milk has always been difficult, mainly because oat starch is prone to aging during storage; protein is prone to denaturation during heat treatment and aggregates to form precipitates; oil floats and other reasons, and its stability is poor.

In order to solve the above problems, amylase is usually used in the production of oat milk in the prior art to degrade starch into dextrin and small molecular sugars, so as to reduce the rough taste and precipitation caused by starch aging. However, enzymatic hydrolysis conditions are generally strict, and the enzymatic hydrolysis takes a long time and consumes more energy. Secondly, various stabilizers and thickeners are also used in the production of oat milk beverages, but the cost is often high.

Contents of the invention

The object of the present invention is to provide a method for preparing plant-based oat milk with good stability, which saves cost and energy and can be continuously produced. The specific plan is as follows:

(1) After cleaning the oatmeal, place it in a pulverizer and pulverize it to obtain oat flour, make it 100% pass through a 60-mesh sieve, fully mix the oat flour and α-amylase, and obtain mixed oat flour;

(2) Reactively extrude the oat flour obtained in step (1) in a twin-screw extruder; the extrusion temperature is 25°C-110°C, the feeding speed is 0.1-1kg/h, and the screw speed is 100-180r/min , the water content of the mixed material is 30% to 70%, and the prefabricated mixture is obtained;

(3) Mix the prefabricated mixture obtained in step (2) according to the material-to-liquid ratio of 1:8 to 1:15, and beat for 10 to 20 minutes;

(4) heating the product obtained in step (3) at 85° C. to 100° C. for 20 to 30 minutes to inactivate the enzyme;

(5) The product obtained in step (4) is subjected to ultrasonic dispersion, filtration, preparation, homogenization, sterilization, and filling to obtain the finished oat milk.

Preferably, the α-amylase in step (1) is a mixture of one or several kinds of medium-temperature α-amylase and high-temperature α-amylase in any proportion, and the added amount is 0.05% to 0.5% of the mass of oat flour.

Preferably, the conditions for ultrasonic dispersion in step (5) are: ultrasonic power 200-500W, ultrasonic frequency 30Hz.

Preferably, a 250-mesh sieve is used when filtering in step (5).

Preferably, in step (5), the preparation substances added to the oat slurry are edible salt and vegetable oil, and the amount of the edible salt and vegetable oil added is 1-4% of the mass of the oat slurry.

Preferably, the homogenization pressure in the homogenization process in step (5) is 30-60 MPa, and the homogenization times are 1-2 times.

Preferably, the sterilization conditions in step (5) are: sterilization temperature 80-100° C., sterilization time 15-20 minutes.

Compared with the prior art, the above solution of the embodiment of the present invention has the following beneficial effects:

The present invention combines extrusion technology with enzymatic hydrolysis technology to form a processing method of adding enzyme extrusion. Extrusion is a high-temperature, short-time, continuous multifunctional thermomechanical technology, which integrates mixing, stirring, shearing and so on of materials. Cutting, heating, cooking, forming and other operating units are integrated to achieve continuous high productivity. Enzyme extrusion is to use the extruder as an enzyme-catalyzed bioreactor, and introduce exogenous enzyme preparations during the extrusion process to assist extrusion and strengthen the action on enzyme substrates. During the enzyme extrusion process, the enzyme presents a center-to-outward radial action path on the substrate, and mechanical actions such as screw shear and pressure can induce enzyme activation, showing high-efficiency activity. Save time and effort, save energy, and be able to produce continuously. The finished oat milk has good stability and good taste.

Description of drawings

Fig. 1 is a schematic diagram of the preparation process of the present invention;

Fig. 2 is the oat milk sensory evaluation scoring rule of the present invention.

Detailed ways

The technical solutions in the embodiments of the present invention will be fully and clearly described below. Apparently, the described embodiments are only some of the embodiments of the present invention, not all of them.

Example 1

A preparation method of oat milk beverage, comprising the following steps:

(1) After the oats are cleaned, they are pulverized in a pulverizer, so that 100% of the particles pass through a 60-mesh sieve to obtain oat flour;

(2) Mix the oat flour with 0.1% mesophilic α-amylase evenly to form mixed oat flour;

(3) Reactively extrude the mixed oat flour in a twin-screw extruder. Material speed 0.3kg/h, screw speed 150r/min, water content is 50% of oat flour dry weight, obtains prefabricated mixture;

(4) beating the prefabricated mixture and water at a ratio of 1:12 for 15 minutes to obtain oat pulp solution;

(5) bathing the oat pulp solution at 90° C. in water for 30 minutes to inactivate the mesophilic α-amylase to obtain an enzyme-inactivated oat pulp solution;

(6) ultrasonically disperse the enzyme-inactivated oat pulp solution, the ultrasonic conditions are: ultrasonic power 200W, frequency 30Hz, to obtain the first mixed solution;

(7) Pass the first mixed solution through a 250-mesh sieve, filter out impurities such as insoluble bran and foam, improve the stability of the emulsion, and obtain the second mixed solution;

(8) Add 1% edible salt and 1% vegetable oil to the second mixed solution, and mix evenly to obtain the third mixed solution;

(9) Homogenize the third mixed solution twice under the condition of a pressure of 40 MPa to obtain semi-finished oat milk;

(10) The semi-finished oat milk was sterilized at a temperature of 85° C. for 20 minutes, and the sterilized mixed solution was aseptically cold filled to obtain the finished oat milk.

Example 2

A preparation method of oat milk beverage, comprising the following steps:

(1) After the oats are cleaned, they are pulverized in a pulverizer, so that 100% of the particles pass through a 60-mesh sieve to obtain oat flour;

(2) Mixing the oat flour with 0.05% mesophilic α-amylase evenly to form mixed oat flour;

(3) Reactively extrude the mixed oat flour in a twin-screw extruder, wherein the temperatures of the six temperature zones of the extruder are respectively 30°C, 45°C, 60°C, 65°C, 85°C, and 95°C. Material speed 0.3kg/h, screw speed 150r/min, water content is 45% of oat flour dry weight, obtains prefabricated mixture;

(4) beating the prefabricated mixture and water at a ratio of 1:12 for 15 minutes to obtain oat pulp solution;

(5) bathing the oat pulp at 90° C. in water for 30 minutes to inactivate the medium-temperature α-amylase to obtain an enzyme-inactivated oat pulp solution;

(6) ultrasonically disperse the enzyme-inactivated oat pulp solution, the ultrasonic conditions are: ultrasonic power 300W, frequency 30Hz, to obtain the first mixture;

(7) Pass the first mixed solution through a 250-mesh sieve, filter out impurities such as insoluble bran and foam, improve the stability of the emulsion, and obtain the second mixed solution;

(8) Add 1% edible salt and 1% vegetable oil to the second mixed solution, and mix evenly to obtain the third mixed solution;

(9) Homogenize the third mixed solution under a pressure of 50 MPa to obtain semi-finished oat milk;

(10) The semi-finished oat milk was sterilized at a temperature of 85° C. for 20 minutes, and the sterilized mixed solution was aseptically cold filled to obtain the finished oat milk.

Example 3

A preparation method of oat milk beverage, comprising the following steps:

(1) After the oats are cleaned, they are pulverized in a pulverizer, so that 100% of the particles pass through a 60-mesh sieve to obtain oat flour;

(2) Mixing the oat flour with 0.2% mesophilic α-amylase evenly to form mixed oat flour;

(3) Reactively extrude the mixed oat flour in a twin-screw extruder. Material speed 0.3kg/h, screw speed 150r/min, water content is 45% of oat flour dry weight, obtains prefabricated mixture;

(4) beating the prefabricated mixture and water at a ratio of 1:10 for 10 minutes to obtain oat pulp solution;

(5) bathing the oat pulp solution at 90° C. in water for 30 minutes to inactivate the mesophilic α-amylase to obtain an enzyme-inactivated oat pulp solution;

(6) ultrasonically disperse the enzyme-inactivated oat pulp solution, the ultrasonic conditions are: ultrasonic power 500W, frequency 30Hz, to obtain the first mixed solution;

(7) Pass the first mixed solution through a 250-mesh sieve, filter out impurities such as insoluble bran and foam, improve the stability of the emulsion, and obtain the second mixed solution;

(8) Add 1% edible salt and 1% vegetable oil to the second mixed solution, and mix evenly to obtain the third mixed solution;

(9) Homogenize the third mixed solution under a pressure of 20 MPa to obtain semi-finished oat milk;

(10) The semi-finished oat milk was sterilized at a temperature of 85° C. for 20 minutes, and the sterilized mixed solution was aseptically cold filled to obtain the finished oat milk.

Example 4

A preparation method of oat milk beverage, comprising the following steps:

(1) After the oats are cleaned, they are pulverized in a pulverizer, so that 100% of the particles pass through a 60-mesh sieve to obtain oat flour;

(2) Mix the oat flour with 0.2% high-temperature α-amylase evenly to form mixed oat flour;

(3) Reactively extrude the mixed oat flour in a twin-screw extruder. Material speed 0.3kg/h, screw speed 150r/min, water content is 50% of oat flour dry weight, obtains prefabricated mixture;

(4) beating the prefabricated mixture and water at a ratio of 1:10 for 10 minutes to obtain oat pulp solution;

(5) boiling the oat pulp solution in a water bath for 30 minutes to inactivate the high-temperature α-amylase to obtain an enzyme-inactivated oat pulp solution;

(6) ultrasonically disperse the enzyme-inactivated oat pulp solution, the ultrasonic conditions are: ultrasonic power 500W, frequency 30Hz, to obtain the first mixed solution;

(7) Pass the first mixed solution through a 250-mesh sieve, filter out impurities such as insoluble bran and foam, improve the stability of the emulsion, and obtain the second mixed solution;

(8) Add 2% edible salt and 1% vegetable oil to the second mixed solution, and mix evenly to obtain the third mixed solution;

(9) Homogenize the third mixed solution under a pressure of 40 MPa to obtain semi-finished oat milk;

(10) The semi-finished oat milk was sterilized at a temperature of 85° C. for 20 minutes, and the sterilized mixed solution was aseptically cold filled to obtain the finished oat milk.

Comparative example 1

A preparation method of oat milk beverage, comprising the following steps:

(1) After the oats are cleaned, they are pulverized in a pulverizer, so that 100% of the particles pass through a 60-mesh sieve to obtain oat flour;

(2) Reactively extrude the mixed oat flour in a twin-screw extruder. Material speed 0.3kg/h, screw speed 150r/min, water content is 50% of oat flour dry weight, obtains prefabricated mixture;

(3) beating the prefabricated mixture and water at a ratio of 1:12 for 10 minutes to obtain oat pulp solution;

(4) Adjust the pH of the oat pulp solution to about 6, add 0.1% of medium-temperature α-amylase, and enzymolyze and liquefy at 60° C. for 2 hours to obtain an enzymatic hydrolyzed oat pulp solution;

(5) bathing the oat pulp at 90° C. in water for 30 minutes to inactivate the medium-temperature α-amylase to obtain an enzyme-inactivated oat pulp solution;

(6) ultrasonically disperse the enzyme-inactivated oat pulp solution, the ultrasonic conditions are: ultrasonic power 500W, frequency 30Hz, to obtain the first mixed solution;

(7) Pass the first mixed solution through a 250-mesh sieve, filter out impurities such as insoluble bran and foam, improve the stability of the emulsion, and obtain the second mixed solution;

(8) Add 1% edible salt and 1% vegetable oil to the second mixed solution, and mix evenly to obtain the third mixed solution;

(9) Homogenize the third mixed solution under a pressure of 40 MPa to obtain semi-finished oat milk;

(10) The semi-finished oat milk was sterilized at a temperature of 85° C. for 20 minutes, and the sterilized mixed solution was aseptically cold filled to obtain the finished oat milk.

Comparative example 2

A preparation method of oat milk beverage, comprising the following steps:

(1) After the oats are cleaned, they are pulverized in a pulverizer, so that 100% of the particles pass through a 60-mesh sieve to obtain oat flour;

(2) Reactively extrude the mixed oat flour in a twin-screw extruder. Material speed 0.3kg/h, screw speed 150r/min, water content is 50% of oat flour dry weight, obtains prefabricated mixture;

(3) beating the prefabricated mixture and water at a ratio of 1:10 for 10 minutes to obtain oat pulp solution;

(4) Adjust the pH of the oat pulp solution to about 6, add 0.2% high-temperature α-amylase, and enzymatically hydrolyze and liquefy at 90° C. for 2 hours to obtain an enzymatic hydrolyzed oat pulp solution;

(5) boiling the oat pulp solution in a water bath for 30 minutes to inactivate the high-temperature α-amylase to obtain an enzyme-inactivated oat pulp solution;

(6) ultrasonically disperse the enzyme-inactivated oat pulp solution, the ultrasonic conditions are: ultrasonic power 500W, frequency 30Hz, to obtain the first mixed solution;

(7) Pass the first mixed solution through a 250-mesh sieve, filter out impurities such as insoluble bran and foam, improve the stability of the emulsion, and obtain the second mixed solution;

(8) Add 2% edible salt and 1% vegetable oil to the second mixed solution, and mix evenly to obtain the third mixed solution;

(9) Homogenize the third mixed solution under a pressure of 40 MPa to obtain semi-finished oat milk;

(10) The semi-finished oat milk was sterilized at a temperature of 85° C. for 20 minutes, and the sterilized mixed solution was aseptically cold filled to obtain the finished oat milk.

Comparative example 3

A preparation method of oat milk beverage, comprising the following steps:

(1) Wash the oatmeal, soak it in deionized water for 6h, and bake it at 150°C for 30min to obtain roasted oatmeal;

(2) beating the roasted oatmeal and water at a ratio of 1:12 for 10 minutes to obtain an oat pulp solution;

(3) Adjust the pH of the oat pulp solution to about 6, add 0.1% of medium-temperature α-amylase, and enzymatically hydrolyze and liquefy at 60° C. for 2 hours to obtain an enzymatic hydrolyzed oat pulp solution;

(4) bathing the oat pulp solution at 90° C. in water for 30 minutes to inactivate the mesophilic α-amylase to obtain an enzyme-inactivated oat pulp solution;

(5) ultrasonically disperse the enzyme-inactivated oat pulp solution, the ultrasonic conditions are: ultrasonic power 500W, frequency 30Hz, to obtain the first mixed solution;

(6) passing the first mixed solution through a 250-mesh sieve, filtering out impurities such as insoluble bran and foam, improving the stability of the emulsion, and obtaining the second mixed solution;

(7) Add 1% edible salt and 1% vegetable oil to the second mixed solution, and mix evenly to obtain the third mixed solution;

(8) Homogenize the third mixed solution under a pressure of 40 MPa to obtain semi-finished oat milk;

(9) The semi-finished oat milk was sterilized at a temperature of 85° C. for 20 minutes, and the sterilized mixed solution was aseptically cold filled to obtain the finished oat milk.

The separation index, particle size and viscosity of the oat milk of Examples 1-4 and Comparative Examples 1-3 were detected, and the products were sensory evaluated, and the results are shown in Table 1. The separation index, particle size, viscosity, and sensory evaluation methods are as follows:

Separation index: Transfer the oat milk to 50ml graduated centrifuge tubes, fill each centrifuge tube with 30ml samples, seal and store under refrigerated conditions (4°C) to evaluate phase separation, after 96h, according to formula (1) Calculation of Separation Index

SI(%)=(1-(H _S /H _T ))×100% (1)

Among them, _HT represents the total height of the beverage (mm), _{and HS} represents the height of the upper phase (mm)

Particle size: Use a particle size distribution analyzer to analyze the particle size of the sample. The particle size measurement range is 0.01-2000 μm. Stop adding samples when the shading reaches 8%, and save the particle size distribution results after the detection is completed. Particle size results are expressed as D90, where 90% of the particles are smaller than or equal to this width.

Viscosity: Take an appropriate amount of oat milk that is shaken well, add samples according to the requirements of the instrument, select a 40mm plate, and measure the viscosity of the sample at 25°C and a shear rate of 2s ^-1 .

Sensory evaluation: 100 people were randomly selected as test volunteers, and the appearance, flavor, and mouthfeel of each oat milk drink were evaluated, with a full score of 100 points. A total of 98 valid results were retrieved. The specific evaluation method is shown in Figure 2.

Except for the sensory evaluation, all experiments were repeated three times, and the results were expressed as mean ± standard deviation. SPSS 26.0 software was used to perform one-way analysis of variance and Duncan test on the data, and p<0.05 was considered statistically significant.

Table 1

Separation index (%) Particle size (μm) Viscosity (mPa·s) Sensory score Example 1 97.46± ^0.32b 25.57± ^2.33b 214.32± ^5.63b 87.88±3.21 ^a Example 2 96.88± ^0.56c 30.88± ^2.21d 182.76± ^3.94c 85.23± ^4.56c Example 3 99.21±1.02 ^a 22.63±0.88 ^a 235.46±4.33 ^a 87.63±4.98 ^a Example 4 99.65±0.21 ^a 21.92±3.20 ^a 237.50±2.56 ^a 86.45± ^2.33b Comparative example 1 95.76±1.33 ^d 39.03± ^3.78e 106.28± ^2.78e 84.92± ^2.41c Comparative example 2 94.23± ^2.11e 30.52± ^4.20d 128.54±5.32 ^d 83.12± ^3.50d Comparative example 3 75.63± ^2.51f 27.33± ^1.22c 23.21± ^0.78f 82.47± ^5.48e

From the test results of the examples and comparative examples, it can be seen that the larger the separation index, the lower the upper phase height, the less molecular sedimentation, and the better the stability; since the sedimentation velocity of the particles is proportional to the diameter of the particles, the smaller the particle size is, the more stable it is. The better the stability; within a certain range, the greater the viscosity, the better the stability of the emulsion. Compared with the traditional baking and enzymatic hydrolysis method, the production method of enzyme extrusion can significantly improve the stability and sensory score of oat milk; There were also beneficial effects on sexual and sensory scores. At the same time, it can save a lot of water resources and enzymatic hydrolysis time. There is no significant difference in the effect of using mid-temperature amylase and high-temperature amylase, but high-temperature amylase requires a higher temperature and consumes more energy.

Claims (10)

1. A preparation method of oat milk with good stability is characterized by comprising the following steps:

firstly, crushing oat rice, and sieving the crushed oat rice with a 60-mesh sieve to obtain oat flour; uniformly mixing the oat flour with amylase to form mixed oat flour; reactive extrusion of the mixed oat flour in a twin-screw extruder to obtain a pre-prepared mixture; pulping, inactivating enzyme, performing ultrasonic dispersion, filtering, blending, homogenizing, sterilizing and filling the prefabricated mixture to obtain the finished oat milk.

2. The method for preparing oat milk with good stability according to claim 1, wherein the amylase is a mixture of one or more of medium-temperature alpha-amylase and high-temperature alpha-amylase in any proportion, and the addition amount of the amylase is 0.05% -0.5% of the mass of the oat flour.

3. The preparation method of oat milk with good stability according to claim 1, wherein the conditions of the twin-screw extruder are extrusion temperature 25-110 ℃, feeding speed 0.1-1 kg/h, screw rotation speed 100-180 r/min, and water content of the mixed material is 30% -70%.

4. The method for preparing oat milk of claim 1 wherein the ratio of the pre-formed oat flour to water is 1: 8-1: 15, pulping for 10-20 min.

5. The method for preparing oat milk of claim 1, wherein the enzyme deactivation temperature is 85-100 ℃ and the enzyme deactivation time is 20-30 min.

6. The method for preparing oat milk of claim 1 wherein the conditions of ultrasonic dispersion are: the ultrasonic power is 200-500W, and the ultrasonic frequency is 30Hz.

7. The method of claim 1, wherein the filtration is performed using a 250 mesh screen.

8. The preparation method of oat milk with good stability according to claim 1, wherein the blending materials added during blending are table salt and vegetable oil, and the adding amount of the table salt and the vegetable oil is 1-4% of the mass of the oat pulp solution.

9. The method for preparing oat milk of claim 1 wherein the homogenization pressure is 30-60 MPa and the number of homogenization is 1-2.

10. The method for preparing oat milk of claim 1 wherein the sterilization process is: sterilizing temperature is 80-90 deg.c and sterilizing time is 15-20 min.

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