阅读说明：本技术 一种燕麦乳饮料的制备方法 (Preparation method of oat milk beverage ) 是由 张卫强 谭志超 王辉斌 张存存 万方云 于 2021-09-24 设计创作，主要内容包括：本发明公开了一种燕麦乳饮料的制备方法。以燕麦原粮为原料,燕麦原粮经过热水保温灭酶处理,采用胶体磨研磨湿法粉碎,粉碎后的物料采用中温淀粉酶结合糖化酶液化和糖化,物料再经过热处理,使燕麦蛋白空间结构适度变性,离心分离去除残渣；在物料中添加木瓜蛋白酶对燕麦蛋白进行改性；得到的物液中加入适量植物油以及无机盐,经过乳化分散机混匀,均质机均质,超高温瞬时灭菌后,无菌灌装得到燕麦乳。该方法得到燕麦乳产品口感滑润醇厚,色泽乳白,产品乳液稳定性良好,不需要添加其它乳化剂或者增稠剂,且在保持高含量可溶性膳食纤维β-葡聚糖的同时,不会使蛋白质变性严重。制备的燕麦乳可以直接饮用或者搭配咖啡奶茶等使用。(The invention discloses a preparation method of an oat milk beverage. The method comprises the following steps of taking oat raw grain as a raw material, carrying out hot water heat preservation and enzyme deactivation treatment on the oat raw grain, grinding the oat raw grain by a colloid mill through a wet method, liquefying and saccharifying the crushed material by adopting medium-temperature amylase combined with saccharifying enzyme, carrying out heat treatment on the material to moderately modify the space structure of oat protein, and carrying out centrifugal separation to remove residues; adding papain into the material to modify the oat protein; adding appropriate amount of vegetable oil and inorganic salt into the obtained solution, mixing with emulsifying disperser, homogenizing with homogenizer, sterilizing at ultrahigh temperature, and aseptic packaging to obtain oat milk. The oat milk product obtained by the method has smooth and mellow taste, milky color and good stability, does not need to add other emulsifying agents or thickening agents, and does not cause serious protein denaturation while keeping high content of soluble dietary fiber beta-glucan. The prepared oat milk can be directly drunk or used together with coffee milk tea and the like.)

1. The preparation method of the oat milk beverage is characterized by comprising the following steps of:

a) and (3) heat preservation and enzyme inactivation by hot water: adding oat raw grain into hot water of 90-95 deg.C at a solid-to-liquid ratio of 1:6-1:12, heating and maintaining for 5-15min, and cooling to 45-55 deg.C;

b) wet grinding with a colloid mill: grinding the material obtained after the enzyme deactivation in the step a) by using a colloid mill and sieving;

c) liquefying and saccharifying oat starch: controlling the temperature of the sieved material in the step b) at 65-75 ℃, and adding medium-temperature amylase and maltose saccharifying enzyme for enzymolysis;

d) heat-denatured oat protein: heating the feed liquid subjected to enzymolysis in the step c) to 90-95 ℃, and preserving the heat for 20-40 min;

e) centrifugal separation: carrying out centrifugal separation on the feed liquid subjected to heat preservation in the step d) to obtain an enzymolysis liquid, and removing filter residues;

f) concentration: decompressing and concentrating the enzymolysis liquid obtained in the step e) to obtain oat emulsion with the solid content of 10-12%;

g) modification of protease: controlling the temperature of the oat emulsion obtained in the step f) at 50-60 ℃, carrying out enzymolysis by adopting protease for 60-120min, heating to 80-85 ℃, and inactivating the enzyme;

h) emulsification and dispersion: adding the oat emulsion obtained in the step g) after enzymolysis, inorganic salt and vegetable oil into an emulsifying dispersion machine, controlling the temperature to be 60-70 ℃, and emulsifying and dispersing.

2. The preparation method of the oat milk beverage according to claim 1, characterized by further comprising the following steps after emulsification and dispersion:

I) homogenizing: homogenizing the emulsified and dispersed materials by a homogenizer under the homogenizing pressure of 35-45 Mpa;

J) and (3) sterilization: UHT ultrahigh temperature instantaneous sterilization is adopted, the temperature is 145 ℃ at 135-;

K) and (5) sterile filling.

3. The method for preparing an oat milk beverage according to claim 1, wherein the oat raw grain of step a) comprises naked oat or oat groats after hulling.

4. The method for preparing oat milk beverage according to claim 1, wherein the amount of the medium temperature amylase and the maltose saccharifying enzyme added in step c) is 0.1-0.3% of the mass of the oat raw grain.

5. The preparation method of oat milk beverage according to claim 4, characterized in that the enzymolysis time of the medium temperature amylase and the maltose saccharifying enzyme in the step c) is 30-120 min.

6. The preparation method of the oat milk beverage according to claim 1, characterized in that the specific operation of the step e) is as follows: centrifuging with a horizontal screw machine at 3000r/min to obtain enzymolysis solution, adding hot water in an amount of 1:6-1:12 times of the oat raw grain into the residue, stirring, mixing, and centrifuging again to obtain enzymolysis solution; and combining the two enzymolysis solutions, and removing filter residues.

7. The method for preparing oat milk beverage according to claim 1, wherein the protease in step g) is papain.

8. The preparation method of the oat milk beverage according to claim 7, wherein the dosage of the papain in the step g) is 0.05-0.3% of the mass of the oat raw grain, and the hydrolysis degree of protein in the oat is 2.5-3.5%.

9. The method for preparing oat milk beverage according to claim 1, wherein the inorganic salt in step h) is any one of sodium chloride, potassium chloride, a mixture of sodium chloride and potassium chloride, sodium carbonate, dipotassium hydrogen phosphate or a mixture of sodium carbonate and dipotassium hydrogen phosphate; when the inorganic salt is sodium chloride, potassium chloride, a mixture of sodium chloride and potassium chloride, the addition amount of the inorganic salt is 0.3-1.0% of the mass of the oat raw grain; when the inorganic salt is sodium carbonate, dipotassium hydrogen phosphate or the mixture of sodium carbonate and dipotassium hydrogen phosphate, the addition amount of the inorganic salt is 0.4-2.0% of the mass of the oat raw grain.

10. The preparation method of the oat milk beverage according to claim 1, wherein the vegetable oil in the step h) is any one or more of rapeseed oil, grape seed oil, almond oil and pumpkin seed oil, and the addition amount of the vegetable oil is 10-25% of the mass of the oat raw grain.

Technical Field

The invention belongs to the field of deep processing of oat, and particularly relates to a preparation method of an oat milk beverage.

Background

The beverage produced and processed based on the oat is a novel product appearing at home and abroad in recent years, is often called oat milk or oat milk, and can be directly drunk or blended with various beverages such as coffee, milk tea and the like due to the appearance and the mouthfeel similar to those of milk products. The oat milk is rich in nutrition, the protein content, the dietary fiber content and the unsaturated fatty acid content are high, the oat flavor is unique, the oat milk is suitable for people of all ages, the oat milk has good market prospect, and the oat milk is a plant protein drink with great potential after the soybean milk. As a representative of plant-based food, the oat milk beverage product does not contain lactose and allergic components, which provides good selection for lactose intolerant people and consumers with milk protein allergy, soybean protein sensitivity, nut allergy and the like.

The first problem in the production of the traditional oat milk beverage is the enzyme deactivation problem of lipoxidase and beta-glucanase in oat raw grains, the enzyme deactivation is carried out by superheated steam in the current industrial production, the enzyme deactivation temperature is about 160 ℃, and the enzyme deactivation can cause serious denaturation of protein in oat at the temperature; in addition, in the process of preparing the oat milk product, vegetable oil is required to be added to prepare the emulsion in order to improve the mellow feeling of the product, but because proteins in the oat are mainly globulin with a compact structure and have poor emulsifying performance, an emulsifier or a thickener is usually required to be added to improve the stability of the product in the process of preparing the oat milk, and at present, a clean label is pursued in the food and beverage market, so that safer and healthier food is provided for consumers, and excessive food additives do not meet the trend of times.

Disclosure of Invention

The invention overcomes the problems in the prior art and provides the oat milk beverage

A preparation method. The method fully mobilizes and exerts the emulsifying performance of the protein in the oat on the premise of killing lipoxygenase and beta-glucanase, thereby achieving the purposes of stabilizing an oat emulsion system and prolonging the shelf life of the product. The purpose of the invention is realized by the following technical scheme:

a preparation method of oat milk beverage comprises the following steps:

a) and (3) heat preservation and enzyme inactivation by hot water: adding oat raw grain into hot water of 90-95 deg.C at a solid-to-liquid ratio of 1:6-1:12, heating and maintaining for 5-15min, and cooling to 45-55 deg.C.

By adopting a hot water enzyme deactivation process, the lipoxidase and beta-glucanase in the oat can be killed by heating hot water at 90-95 ℃ for a short time to deactivate the enzyme. The lipoxidase is mainly present in an aleurone layer of the oat, and if enzyme deactivation treatment is not carried out, fat in the product is hydrolyzed and oxidized, so that the shelf life of the product is shortened, and the rancid taste and the bitter taste of the product are increased. In addition, the oat contains a functional component beta-glucan which has multiple physiological functions, can reduce the absorption of cholesterol and prevent cardiovascular diseases, also has the effects of regulating the blood sugar level and improving the intestinal microenvironment and has prebiotic effect, but if the beta-glucanase exists, the beta-glucan in the oat can be degraded, so that the loss of the functional component of the product is caused.

b) Wet grinding with a colloid mill: grinding the material obtained after the enzyme deactivation in the step a) by using a colloid mill and sieving the ground material.

c) Liquefying and saccharifying oat starch: controlling the temperature of the sieved material in the step b) at 65-75 ℃, and adding medium-temperature amylase and maltose saccharifying enzyme for enzymolysis.

The method adopts a starch liquefying and saccharifying process, firstly adopts medium-temperature amylase for enzymolysis, controls the content (DE value) of starch sugar to be 15-18%, then adopts maltose saccharifying enzyme for enzymolysis, and a small amount of maltose exists in the product after enzymolysis, so that the sweetness of the product is increased, the drinking oat milk beverage has aftersweet feeling, and other food raw materials or additives such as white granulated sugar and the like do not need to be added in the blending process. The use of additives is reduced.

d) Heat-denatured oat protein: heating the feed liquid subjected to enzymolysis in the step c) to 90-95 ℃, and preserving the heat for 20-40 min.

Heat-denatured oat protein: the protein content in oats is between 11-19%, averaging around 14%, with 50-60% being globulins, most of which have relatively ordered, denser and stable higher order structures with most of the hydrophobic groups hidden inside the spherical structure and most of the hydrophilic groups exposed outside the spherical structure. Although it has good hydrophilicity, poor lipophilicity still limits its application in the field of emulsions. The three-dimensional structure of globulin is maintained by covalent bonds, hydrogen bonds, hydrophobic interactions, electrostatic attraction, van der waals forces and the like among different amino acids in a molecule, so that the structure and the emulsifying property of globulin can be changed to different degrees by all factors which can appropriately damage the acting forces. In the project, the oat protein is properly denatured through heating and heat preservation, so that the internal structure of the oat protein is loose, hydrophobic groups are exposed, and the flexibility of the structure of the oat protein is enhanced; the emulsifying property is improved, and simultaneously, more enzymolysis sites are provided for the modification of protease.

e) Centrifugal separation: and d) carrying out centrifugal separation on the feed liquid subjected to heat preservation in the step d) to obtain an enzymolysis liquid, and removing filter residues.

f) Concentration: decompressing and concentrating the enzymolysis liquid obtained in the step e) to obtain the oat emulsion with the solid content of 10-12%.

g) Modification of protease: controlling the temperature of the oat emulsion obtained in the step f) at 50-60 ℃, carrying out enzymolysis by adopting protease for 60-120min, heating to 80-85 ℃, and inactivating the enzyme.

h) Emulsification and dispersion: adding the oat emulsion obtained in the step g) after enzymolysis, inorganic salt and vegetable oil into an emulsifying dispersion machine, controlling the temperature to be 60-70 ℃, and emulsifying and dispersing.

The addition of a proper amount of inorganic salt in the product mainly adjusts the ionic strength and the pH value of materials, is beneficial to keeping protein away from isoelectric points, destroys the hydration of the surface of the protein, and improves the emulsifying property of the product by a physical method. Vegetable oil, especially some functional oil with polyunsaturated fatty acid is added into the product, so that the purpose of improving the mouthfeel of the emulsion can be achieved, and the product has better product functionality.

Further optimization, the method also comprises the following steps after emulsification and dispersion:

I) homogenizing: homogenizing the emulsified and dispersed materials by a homogenizer under the homogenizing pressure of 35-45 Mpa;

J) and (3) sterilization: UHT ultrahigh temperature instantaneous sterilization is adopted, the temperature is 145 ℃ at 135-;

K) and (5) sterile filling.

Further, the oat raw grain of the step a) comprises naked oats or skin oats after husking.

In the aspect of saccharification, the addition amount of the medium-temperature amylase and the maltose saccharifying enzyme in the step c) is 0.1-0.3 percent of the mass of the oat raw grain. The enzymolysis time of the moderate temperature amylase and the maltose saccharifying enzyme in the step c) is 30-120 min.

Further optimization in terms of centrifugation, the specific operations of step e) are: centrifuging with a horizontal screw machine at 3000r/min to obtain enzymolysis solution, adding hot water in an amount of 1:6-1:12 times of the oat raw grain into the residue, stirring, mixing, and centrifuging again to obtain enzymolysis solution; and combining the two enzymolysis solutions, and removing filter residues.

Further optimization in terms of enzyme modification, the protease of step g) is papain. The dosage of the papain in the step g) is 0.05 to 0.3 percent of the mass of the oat raw grain, and the hydrolysis degree of protein in the oat is 2.5 to 3.5 percent.

According to the invention, the papain is adopted to modify the oat protein, protein molecules after mild enzymolysis have better emulsifying performance, which is an important way for improving the emulsifying performance of modified protein by a biological method, and the formed emulsion has better stability by controlling the degree of hydrolysis of the protein to be between 2.5 and 3.5 percent, and the product has no bitter taste. The emulsifying activity of proteins is highly dependent on the degree to which they reduce interfacial tension, and the ease with which they diffuse, penetrate, unfold and rearrange at the interface, with the improvement in emulsifying properties of globulins being associated with a reduction in molecular weight.

Further optimization in emulsification aspect, the inorganic salt in step h) is any one of sodium chloride, potassium chloride, a mixture of sodium chloride and potassium chloride, sodium carbonate, dipotassium hydrogen phosphate or a mixture of sodium carbonate and dipotassium hydrogen phosphate; when the inorganic salt is sodium chloride, potassium chloride, a mixture of sodium chloride and potassium chloride, the addition amount of the inorganic salt is 0.3-1.0% of the mass of the oat raw grain; when the inorganic salt is sodium carbonate, dipotassium hydrogen phosphate or the mixture of sodium carbonate and dipotassium hydrogen phosphate, the addition amount of the inorganic salt is 0.4-2.0% of the mass of the oat raw grain.

Further, the vegetable oil in the step h) is any one or more of rapeseed oil, grape seed oil, almond oil and pumpkin seed oil, and the addition amount of the vegetable oil is 10-25% of the mass of the oat raw grain.

The invention has the beneficial effects that:

the oat milk product obtained by the method has smooth and mellow taste, milky color and good stability, and does not need to add other emulsifying agents or thickening agents. And does not denature protein seriously while keeping high content of soluble dietary fiber beta-glucan.

The oat milk prepared by the method can be directly drunk or used together with coffee milk tea and the like, and can have natural light and sweet mouthfeel without adding sugar.

The method is green and environment-friendly, is suitable for industrial production, and reduces the use of food additives as much as possible in the process.

Detailed Description

The invention is further described with reference to the following examples:

example 1

A preparation method of oat milk beverage comprises the following specific operations:

adding water for production into an enzyme deactivation tank, heating to 90-95 deg.C, adding naked oat raw grain according to a material-to-liquid ratio of 1:6, heating and keeping the temperature for 10min, and cooling to 50 deg.C with cold water in a jacket; grinding the materials by a colloid mill, and controlling the fineness of the materials to pass through a 80-mesh sieve; adding medium-temperature amylase and maltose glucoamylase into an enzymolysis tank, wherein the addition amount of the medium-temperature amylase and the maltose glucoamylase is 0.12 percent of that of raw naked oat grains, and the enzymolysis time is 90min at 70 ℃; heating the material to 90-95 deg.C, and maintaining the temperature for 30 min; centrifuging with a horizontal screw machine at 3000r/min to obtain enzymolysis solution, placing the residue in an enzymolysis tank, adding 6 times of production water, heating to 70 deg.C, stirring, maintaining for 15min, centrifuging again to obtain secondary enzymolysis solution, and mixing the two enzymolysis solutions; concentrating the enzymolysis solution under reduced pressure to solid content of 10-12%; controlling the temperature to be 50 ℃ in a protein modification tank, adding papain for modification, wherein the adding amount of the papain is 0.15 percent of that of the oat raw grain, performing enzymolysis for 90min to obtain oat protein with the hydrolysis degree of 3.2 percent, and heating to 85 ℃ to inactivate enzyme for 15 min; adding the materials into an emulsifying dispersion machine, adding 0.6% of sodium chloride and 1.5% of dipotassium hydrogen phosphate into the oat raw grain, dissolving, adding 18% of grape seed oil into the oat raw grain, emulsifying and dispersing uniformly at 70 ℃, homogenizing by using a homogenizer with the homogenizing pressure of 40MPa, carrying out ultrahigh-temperature instantaneous sterilization on the obtained materials at 140 ℃ for 8 seconds, and carrying out aseptic packaging on the sterilized materials to obtain the oat milk beverage. (all materials are in mass ratio, the same applies hereinafter.)

Example 2

A preparation method of oat milk beverage comprises the following specific operations:

adding water for production into an enzyme deactivation tank, heating to 90-95 deg.C, adding raw oat grain according to a material-to-liquid ratio of 1:8, keeping the temperature for 15min, and cooling to 47 deg.C with cold water in a jacket; grinding the materials by a colloid mill, and controlling the fineness of the materials to pass through a 80-mesh sieve; adding medium-temperature amylase and maltose glucoamylase into an enzymolysis tank, wherein the addition amount of the medium-temperature amylase and the maltose glucoamylase is 0.1 percent of the raw oat grains, the enzymolysis time is 120min at 70 ℃; heating the material to 90-95 deg.C, and maintaining the temperature for 25 min; centrifuging with a horizontal screw machine at 3000r/min to obtain enzymolysis solution, placing the residue in an enzymolysis tank, adding 6 times of production water, heating to 72 deg.C, stirring, maintaining for 15min, centrifuging again to obtain secondary enzymolysis solution, and mixing the two enzymolysis solutions; concentrating the enzymolysis solution under reduced pressure to solid content of 10-12%; controlling the temperature to 52 ℃ in a protein modification tank, adding papain for modification, wherein the adding amount of the papain is 0.3 percent of the original grain of the oat, carrying out enzymolysis for 60min to obtain the hydrolysis degree of the oat protein of 2.9 percent, and heating to 82 ℃ to inactivate the enzyme for 15 min; adding the materials into an emulsification dispersion machine, adding potassium chloride accounting for 0.6% of raw oat grains and sodium carbonate accounting for 1.4% of raw oat grains, dissolving, adding rapeseed oil accounting for 21% of raw oat grains, emulsifying and dispersing uniformly at 70 ℃, homogenizing by a homogenizer with the homogenizing pressure of 40MPa, carrying out ultrahigh-temperature instantaneous sterilization on the obtained materials at 138 ℃ for 12 seconds, and carrying out aseptic packaging on the sterilized materials to obtain the oat milk beverage.

Example 3

A preparation method of oat milk beverage comprises the following specific operations:

adding water for production into an enzyme deactivation tank, heating to 90-95 deg.C, adding naked oat raw grain according to a material-to-liquid ratio of 1:10, heating and keeping the temperature for 15min, and cooling to 49 deg.C with cold water in a jacket; grinding the materials by a colloid mill, and controlling the fineness of the materials to pass through a 80-mesh sieve; adding medium-temperature amylase and maltose glucoamylase into an enzymolysis tank, wherein the addition amount of the medium-temperature amylase and the maltose glucoamylase is 0.24 percent of that of raw naked oat grains, and the enzymolysis time is 30min at 70 ℃; heating the material to 90-95 deg.C, and maintaining the temperature for 40 min; centrifuging with a horizontal screw machine at 3000r/min to obtain enzymolysis solution, placing the residue in an enzymolysis tank, adding 6 times of production water, heating to 70 deg.C, stirring, maintaining for 15min, centrifuging again to obtain secondary enzymolysis solution, and mixing the two enzymolysis solutions; concentrating the enzymolysis solution under reduced pressure to solid content of 10-12%; controlling the temperature to be 52 ℃ in a protein modification tank, adding papain for modification, wherein the adding amount of the papain is 0.25 percent of that of the oat raw grain, carrying out enzymolysis for 60min to obtain oat protein with the hydrolysis degree of 3.4 percent, and heating to 85 ℃ to inactivate enzyme for 15 min; adding the materials into an emulsifying dispersion machine, adding 0.4% of sodium chloride and 1.2% of dipotassium hydrogen phosphate into the oat raw grain, dissolving, adding 21% of pumpkin seed oil into the oat raw grain, emulsifying and dispersing uniformly at 68 ℃, homogenizing by using a homogenizer with the homogenizing pressure of 40MPa, carrying out ultrahigh-temperature instantaneous sterilization on the obtained materials at 140 ℃ for 10 seconds, and carrying out aseptic packaging on the sterilized materials to obtain the oat milk beverage.

Comparative example 1

A preparation method of oat milk beverage is the comparison of example 1, compared with the comparison document 1, only lacking the steps of hot water heat preservation and enzyme deactivation (namely, adding production water into an enzyme deactivation tank, heating to 90-95 ℃, adding naked oat raw grain according to the feed-liquid ratio of 1:6, heating and heat preservation for 10min, and cooling by introducing cold water into a jacket to 50 ℃), the operation of other steps is the same as that of example 1, the oat raw grain without enzyme deactivation is directly mixed with water, ground and sieved, and the specific operation is as follows:

mixing naked oat raw grain with production water according to the proportion of 1:6, and grinding by using a colloid mill, wherein the fineness of the material is controlled to pass through a 80-mesh sieve; adding medium-temperature amylase and maltose glucoamylase into an enzymolysis tank, wherein the addition amount of the medium-temperature amylase and the maltose glucoamylase is 0.12 percent of that of raw naked oat grains, and the enzymolysis time is 90min at 70 ℃; heating the material to 90-95 deg.C, and maintaining the temperature for 30 min; centrifuging with a horizontal screw machine at 3000r/min to obtain enzymolysis solution, placing the residue in an enzymolysis tank, adding 6 times of production water of oat grains, heating to 70 deg.C, stirring, maintaining for 15min, centrifuging again to obtain secondary enzymolysis solution, and mixing the two enzymolysis solutions; concentrating the enzymolysis solution under reduced pressure to solid content of 10-12%; controlling the temperature in a protein modification tank to 50 ℃, adding papain for modification, wherein the adding amount of the papain is 0.15 percent of that of the oat raw grain, performing enzymolysis for 90min to obtain oat protein with the hydrolysis degree of 3.0 percent, and heating to 85 ℃ to inactivate enzyme for 15 min; adding the materials into an emulsifying dispersion machine, adding 0.6% of sodium chloride and 1.5% of dipotassium hydrogen phosphate into the oat raw grain, dissolving, adding 18% of grape seed oil into the oat raw grain, emulsifying and dispersing uniformly at 70 ℃, homogenizing by using a homogenizer with the homogenizing pressure of 40MPa, carrying out ultrahigh-temperature instantaneous sterilization on the obtained materials at 140 ℃ for 8 seconds, and carrying out aseptic packaging on the sterilized materials to obtain the oat milk beverage.

Comparative example 2

Compared with the comparative document 1, the comparative example is the control of the example 1, and only lacks the step of protease modification (namely, papain is added for modification after the temperature is controlled to be 50 ℃ in a protein modification tank, the adding amount of the papain is 0.15 percent of the original oat grain, the enzymolysis time is 90min, the hydrolysis degree of the oat protein is 3.2 percent, the temperature is increased to 85 ℃ for enzyme deactivation for 15min, the operation of other steps is the same as that of the example 1, the emulsification and dispersion are directly carried out after the reduced pressure concentration of the example, and the specific operation is as follows:

adding appropriate amount of water for production into enzyme inactivating tank, heating to 90-95 deg.C, adding naked oat raw grain with material-to-liquid ratio of 1:6, keeping the temperature for 10min, and cooling to 50 deg.C with cold water in jacket; grinding the materials by a colloid mill, and controlling the fineness of the materials to pass through a 80-mesh sieve; adding medium-temperature amylase and maltose glucoamylase into an enzymolysis tank, wherein the addition amount of the medium-temperature amylase and the maltose glucoamylase is 0.12 percent of that of raw naked oat grains, and the enzymolysis time is 90min at 70 ℃; heating the material to 90-95 deg.C, and maintaining the temperature for 30 min; centrifuging with a horizontal screw machine at 3000r/min to obtain enzymolysis solution, placing the residue in an enzymolysis tank, adding 6 times of production water, heating to 70 deg.C, stirring, maintaining for 15min, centrifuging again to obtain secondary enzymolysis solution, and mixing the two enzymolysis solutions; concentrating the enzymolysis solution under reduced pressure to solid content of 10-12%; adding the materials into an emulsifying dispersion machine, adding 0.6% of sodium chloride and 1.5% of dipotassium hydrogen phosphate into the oat raw grain, dissolving, adding 18% of grape seed oil into the oat raw grain, emulsifying and dispersing uniformly at 70 ℃, homogenizing by using a homogenizer with the homogenizing pressure of 40MPa, carrying out ultrahigh-temperature instantaneous sterilization on the obtained materials at 140 ℃ for 8 seconds, and carrying out aseptic packaging on the sterilized materials to obtain the oat milk beverage.

Comparative example 3

A preparation method of oat milk beverage is provided, wherein the comparative example is the control of example 1, compared with the comparative document 1, the time for only thermally denaturing oat protein is shortened (from 30min to 10min, the temperature of the material in example 1 is raised to 90-95 ℃, and the temperature is kept for 30 min), the operation of other steps is the same as that in example 1, and the specific operation is as follows:

adding appropriate amount of water for production into enzyme inactivating tank, heating to 90-95 deg.C, adding naked oat raw grain with material-to-liquid ratio of 1:6, heating to 90-95 deg.C, keeping the temperature for 10min, and cooling to 50 deg.C with cold water in jacket; grinding the materials by a colloid mill, and controlling the fineness of the materials to pass through a 80-mesh sieve; adding medium-temperature amylase and maltose glucoamylase into an enzymolysis tank, wherein the addition amount of the medium-temperature amylase and the maltose glucoamylase is 0.12 percent of that of raw naked oat grains, and the enzymolysis time is 90min at 70 ℃; heating the material to 90-95 deg.C, and keeping the temperature for 10min (only enzyme deactivation is achieved, and protein denaturation degree is not achieved); centrifuging with a horizontal screw machine at 3000r/min to obtain enzymolysis solution, placing the residue in an enzymolysis tank, adding 6 times of production water, heating to 70 deg.C, stirring, maintaining for 15min, centrifuging again to obtain secondary enzymolysis solution, and mixing the two enzymolysis solutions; vacuum concentrating the enzymolysis liquid to solid content of 10-12%; controlling the temperature to be 50 ℃ in a protein modification tank, adding papain for modification, wherein the adding amount of the papain is 0.15 percent of that of the oat raw grain, performing enzymolysis for 90min to obtain oat protein with the hydrolysis degree of 3.0 percent, and heating to 85 ℃ to inactivate enzyme for 15 min; adding the materials into an emulsifying dispersion machine, adding 0.6% of sodium chloride and 1.5% of dipotassium hydrogen phosphate into the oat raw grain, dissolving, adding 18% of grape seed oil into the oat raw grain, emulsifying and dispersing uniformly at 70 ℃, homogenizing by using a homogenizer with the homogenizing pressure of 40MPa, carrying out ultrahigh-temperature instantaneous sterilization on the obtained materials at 140 ℃ for 8 seconds, and carrying out aseptic packaging on the sterilized materials to obtain the oat milk beverage.

Comparative example 4

A preparation method of oat milk beverage is a comparison example of example 1, compared with a comparison document 1, only a step of keeping hot water warm and inactivating enzyme is changed into high-temperature steam to inactivate enzyme (in example 1, production water is added into an enzyme inactivation tank, the temperature is heated to 90-95 ℃, naked oat raw grain is added according to a feed-liquid ratio of 1:6, after heating and heat preservation are carried out for 10min, a jacket is filled with cold water to cool to 50 ℃), the operation of other steps is the same as that of example 1, in the example, after high-temperature steam inactivation, the oat raw grain is ground and sieved after being mixed with water, and the specific operation is as follows:

selecting commercially available cured naked oat (steam at 160 ℃, drying after 30min enzyme deactivation), mixing the material with production water in a ratio of 1:6, grinding by using a colloid mill, and controlling the fineness of the material to pass through a 80-mesh sieve; adding medium-temperature amylase and maltose glucoamylase into an enzymolysis tank, wherein the addition amount of the medium-temperature amylase and the maltose glucoamylase is 0.12 percent of that of raw naked oat grains, and the enzymolysis time is 90min at 70 ℃; heating the material to 90-95 deg.C, and maintaining the temperature for 30 min; centrifuging with a horizontal screw machine at 3000r/min to obtain enzymolysis solution, placing the residue in an enzymolysis tank, adding 6 times of production water, heating to 70 deg.C, stirring, maintaining for 15min, centrifuging again to obtain secondary enzymolysis solution, and mixing the two enzymolysis solutions; vacuum concentrating the enzymolysis liquid to solid content of 10-12%; controlling the temperature to be 50 ℃ in a protein modification tank, adding papain for modification, wherein the adding amount of the papain is 0.15 percent of that of the oat raw grain, performing enzymolysis for 90min to obtain the oat protein with the hydrolysis degree of 2.4 percent, and heating to 85 ℃ to inactivate enzyme for 15 min; adding the materials into an emulsifying dispersion machine, adding 0.6% of sodium chloride and 1.5% of dipotassium hydrogen phosphate into the oat raw grain, dissolving, adding 18% of grape seed oil into the oat raw grain, emulsifying and dispersing uniformly at 70 ℃, homogenizing by using a homogenizer with the homogenizing pressure of 40MPa, carrying out ultrahigh-temperature instantaneous sterilization on the obtained materials at 140 ℃ for 8 seconds, and carrying out aseptic packaging on the sterilized materials to obtain the oat milk beverage.

Comparison of product quality between examples 1 to 3 and comparative examples 1 to 4

The detection method comprises the following steps:

1. evaluation of emulsion stability

Taking 20ml of oat emulsion, diluting by 10 times, centrifuging at 3000R/min for 10min, taking supernatant, dividing the supernatant by the wavelength of 785nm to determine the absorbance value A, and then calculating the stability coefficient R value of the beverage according to the following formula:

stability factor R = a_{Rear end}/A_{Front side}

In the formula A_{Front side}Refers to the absorbance value of the diluted oat milk beverage, A_{Rear end}Refers to the absorbance value of the oat milk beverage after dilution and centrifugation. The greater the R value, the more stable the beverage and the longer the shelf life. When the R value is less than 0.8, the beverage is layered within 1 day, R is more than or equal to 0.8 and less than or equal to 0.93, protein particles are obviously precipitated after one week, R is more than or equal to 0.97, and the beverage is in a stable state within three months.

2. The content of the beta-glucan in the oat milk beverage is detected according to a method for measuring the content of the beta-glucan in the grains and products thereof in the agricultural industry standard NY/T2006-2011 of the people's republic of China.

The test results are compared as follows:

1. data for direct assay after sample preparation were as follows:

2. sensory evaluation of samples after 2 months of accelerated stability on standing: (37 ℃ C., relative humidity 75%)

As can be seen from the comparison of the data in the above examples, the direct preparation of oat milk beverage from oat raw grain (comparative example 1) can cause the lipoxygenase and beta-glucanase in the oat aleurone layer to contact with the grease and beta-glucan in the crushing process, and the enzymatic reaction efficiency is very high, which can cause the quick decomposition of the grease and glucan, the reduction of the glucan content in the product and the rancidity oxidation of the grease, so that the product has a rancid taste and the mouthfeel becomes bitter.

Comparative example 4 oat milk beverage prepared with oat inactivated by superheated steam had a slightly poor stability, mainly due to excessive denaturation and inactivation of protein at too high temperature.

The physical heat denaturation alone (comparative example 2) or the biological enzyme modification alone (comparative example 3) can not achieve the ideal requirement of improving the emulsifying property of the product.

The invention adopts the heat denaturation oat globulin, combines the biological enzyme to modify the oat protein, and is beneficial to improving the emulsion stability of the product and prolonging the quality guarantee period of the product on the premise of controlling the hydrolysis degree of the protein.

The above embodiments will further assist those skilled in the art to understand the present invention, but should not be construed as limiting the present invention, and any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention. The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.