Making process of highland barley bean curd

Abstract

The invention discloses a making process of highland barley bean curd. The making process comprises the following steps: S1, precise screening and deep pretreatment of highland barley raw materials; s2, performing targeted enzymolysis and microencapsulation treatment on the highland barley component; s3, preparing soybean milk with high solid content; s4, performing steady-state fusion and ultrahigh-pressure homogenization on the highland barley gel base material and the high-solid soybean milk; s5, curdling solidification and gel strengthening; and S6, carrying out compression molding and sterilization. The grain size D90 of the highland barley is reduced to be smaller than or equal to 15 microns through superfine grinding, the rough feeling and granular feeling of the highland barley are fundamentally eliminated in combination with ultrahigh pressure homogenization (100-150 MPa) treatment, endogenous enzymes are activated through short-time germination to degrade antinutritional factors, long-chain beta-glucan is moderately sheared into medium and short chains which are easier to absorb through targeted enzymolysis, and the content of beta-glucan in the highland barley is reduced. Meanwhile, cell walls are destroyed to release nutrition, so that the product retains the characteristics of high dietary fiber and high beta-glucan of the highland barley.

Description

Technical Field

[0001] This invention relates to the field of barley tofu production technology, and more particularly to a barley tofu production process. Background Technology

[0002] Highland barley, a unique grain resource of the Qinghai-Tibet Plateau, is rich in nutrients such as β-glucan, dietary fiber, and protein. Due to its unique health value, it is increasingly favored by consumers. Combining highland barley with traditional soy products (such as tofu) to develop new compound foods that combine the nutritional advantages of both has become an important innovative direction in the food industry. Highland barley tofu can not only enrich the variety of tofu products, but also improve its functional component content, meeting the market's demand for healthy and nutritious foods. Current practices in barley tofu production still face a series of pressing technical challenges that hinder the industrialization of high-quality products. Barley is rich in dietary fiber, especially its cell wall structure and the high viscosity of β-glucan. Directly adding barley flour disrupts the delicate gel network formed by soybean protein, resulting in traditionally made barley tofu generally having a coarse texture, a grainy feel, and poor elasticity, making its taste far inferior to traditional tofu. Therefore, there is a need in this field for an innovative barley tofu production process that can fundamentally solve the above-mentioned technical bottlenecks and develop high-quality barley tofu products with more easily absorbed nutrients. Summary of the Invention

[0003] The purpose of this invention is to address the shortcomings of existing technologies by proposing a process for making highland barley tofu.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: A process for making highland barley tofu includes the following steps: S1: Precise screening and deep pretreatment of barley raw materials; S2: Targeted enzymatic hydrolysis and microencapsulation of barley components; S3: Preparation of high-solids soy milk; S4: Stabilization and ultra-high pressure homogenization of barley gel base material and high-solids soy milk; S5: Spot coagulation and gel strengthening; S6: Compression molding and sterilization.

[0005] As a further aspect of the present invention: step S1 includes: a: Screening for specific highland barley varieties with protein content ≥12% and β-glucan content ≥6%; b: After cleaning and removing impurities from the barley grains, germinate them for 24-36 hours at a temperature of 28℃ and a humidity of 90%. c: Baking the germinated barley at a low temperature of 60-70℃; d: The roasted barley is ultra-finely pulverized to achieve a barley flour particle size of D90≤15μm.

[0006] As a further aspect of the present invention: step S2 includes: a: Mix ultrafine highland barley powder with water in a ratio of 1:8 to make pulp, and adjust the pH and temperature to the optimal range of action of the compound enzyme; b: Add a complex enzyme containing β-glucanase and cellulase for targeted enzymatic hydrolysis. By monitoring the viscosity in real time, the reaction is terminated when the viscosity drops to 40%-50% of the initial value. c: After enzyme inactivation, soy protein isolate powder is added at 50℃ for microencapsulation, wherein the ratio of soy protein isolate to barley solids is 1:2.

[0007] As a further aspect of the present invention: in step S3, the solid content of the final soy milk is precisely controlled at 10%-12% by controlling the grinding and separation parameters.

[0008] As a further embodiment of the present invention: step S4 includes: a: Mix the highland barley-soybean protein composite gel base obtained in step S2 with the high solids soybean milk obtained in step S3 at a ratio of highland barley to soybean dry matter of 25:75; b: The mixed slurry is subjected to ultra-high pressure homogenization at a pressure of 100-150MPa.

[0009] As a further embodiment of the present invention: step S5 includes: a: After the homogenized slurry is boiled and cooled to 82-85℃, a coagulant made of gluconate-δ-lactone and gypsum is used for slurry application. b: After coagulation, the soy milk is slowly cooled from 85℃ to 60℃ within 30 minutes by shaking and cooling to make the finished product elasticity >3.5mm.

[0010] As a further aspect of the present invention, the oscillation cooling process is carried out on a specially designed oscillation cooling device, and the oscillation parameters are controlled to promote the formation and stabilization of the gel network.

[0011] As a further aspect of the present invention: the sterilization process in step S6 adopts ultra-high pressure cold sterilization technology.

[0012] As a further aspect of the present invention: the dry matter ratio of highland barley to soybeans is 25:75, and the product elasticity is >3.5mm.

[0013] As a further embodiment of the present invention, the barley component exists in the form of a microencapsulated complex formed by enzymatically modified medium- and short-chain β-glucan and soybean protein.

[0014] Compared with the prior art, the present invention provides a process for making highland barley tofu, which has the following beneficial effects: 1. By reducing the particle size of highland barley to D90≤15μm through ultra-micro pulverization and combining it with ultra-high pressure homogenization (100-150MPa) treatment, the roughness and graininess of highland barley are fundamentally eliminated. The oscillation cooling gel strengthening technology is used to fully cross-link the protein network, giving the product excellent elasticity (>3.5mm), and finally obtaining high-quality tofu with uniform texture, delicate and smooth texture and full elasticity.

[0015] 2. By activating endogenous enzymes through short-term germination to degrade anti-nutritional factors, and by selectively cleaving long-chain β-glucan into more easily absorbed medium and short chains through targeted enzymatic hydrolysis, while breaking down cell walls to release nutrients, the product not only retains the high dietary fiber and high β-glucan characteristics of highland barley, but also improves the bioavailability of these nutrients, achieving an upgrade from containing nutrients to efficiently releasing nutrients.

[0016] 3. By utilizing the interaction between soy protein isolate and enzymatically hydrolyzed barley components to form a composite gel base, the technical problem of phase separation and water separation easily occurring between barley fiber and soy protein due to their different properties is effectively solved, ensuring that the final product has a uniform and stable structure and is not prone to deterioration during its shelf life.

[0017] 4. The sugars produced during the short germination process bring a natural, slightly sweet flavor to the product, effectively masking the raw and bran-like taste that may exist in barley. The use of compound coagulants and cold sterilization technology (such as HPP) avoids off-flavors caused by overheating, preserving the harmonious and pure flavor of bean and barley aromas to the greatest extent.

[0018] The parts of this device not covered herein are the same as or can be implemented using existing technologies. This invention has a simple structure and is easy to operate. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the process for making highland barley tofu according to the present invention. Detailed Implementation

[0020] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Example

[0021] A process for making highland barley tofu includes the following steps: S1: Precise screening and deep pretreatment of highland barley raw materials Based on the database, a comprehensive analysis and screening of numerous highland barley varieties in the Tibetan production area was conducted; advanced testing technology was used to accurately determine key indicators such as protein content, β-glucan content, and hardness of each highland barley variety. We selected specific highland barley varieties with a protein content of ≥12%, a β-glucan content of ≥6%, and moderate hardness to ensure that the raw materials have excellent nutritional value and processing characteristics, laying a solid foundation for the production of high-quality products in the future. After entering the production line, the barley grains first undergo a multi-stage cleaning and impurity removal process; advanced screening equipment, such as vibrating screens and air separators, is used to effectively remove impurities, dust, stones, and imperfect grains from the barley. The cleaned barley grains are placed in a specially designed controlled-environment germination chamber, with the temperature precisely controlled at 28℃ and humidity at 90%, for a short germination treatment of 24-36 hours. During this process, the endogenous enzymes inside the barley are fully activated, which can specifically degrade anti-nutritional factors and reduce their adverse effects on the human body. At the same time, the germination process also promotes the production of a slight sweetness in the barley, significantly improving its flavor and bringing a more pleasant taste to the product. After germination, the barley enters the low-temperature baking stage, using advanced low-temperature baking equipment to precisely control the temperature at 60-70℃; After being roasted at low temperature, the barley then enters the ultra-fine grinding process. Using advanced ultra-fine grinding technology, by precisely adjusting the parameters of the grinding equipment, such as rotation speed and grinding time, the particle size of the barley flour reaches D90≤15μm, which is far superior to the target macroscopic dispersion requirement of 1μm. S2: Targeted enzymatic hydrolysis and innovative microencapsulation of barley components Ultrafine highland barley powder is mixed with pure water in a precise ratio of 1:8 and stirred thoroughly to form a uniform slurry. Using advanced pH adjustment equipment and temperature control system, the pH value and temperature of the slurry are adjusted to the optimal range of action of the compound enzyme. A complex enzyme is added, which includes multiple enzymes such as β-glucanase and cellulase, and the proportions of each enzyme are optimized. The enzymatic hydrolysis reaction is carried out under mild conditions. The enzymatic hydrolysis process does not aim for complete hydrolysis, but rather, by precisely controlling the hydrolysis time and the amount of enzyme, the long-chain β-glucan in barley is moderately cleaved into medium and short chains, while destroying the cell wall structure and releasing more nutrients. During the enzymatic hydrolysis process, a high-precision viscometer is used to monitor the viscosity changes of the slurry in real time; when the viscosity drops to 40%-50% of the initial value, the enzymatic hydrolysis reaction is stopped immediately to provide ideal raw materials for subsequent microencapsulation. The enzymatically hydrolyzed barley slurry was rapidly heated to 90°C and kept at that temperature for a certain period of time to inactivate the enzyme, ensuring that the enzyme activity was completely lost and preventing the enzymatic hydrolysis reaction from continuing and affecting product quality. The slurry was then cooled to 50°C to prepare for the next step of microencapsulation. At a suitable temperature of 50℃, specially treated soy protein isolate (SPI) powder is slowly added, controlling the ratio of SPI to barley solids to be 1:2; gentle stirring is continuously carried out, utilizing the thermal denaturation characteristics of soy protein at a specific temperature, as well as its interaction with enzymatically hydrolyzed β-glucan; this composite gel base not only has good stability and uniformity, but also provides the product with rich nutrition and a unique taste. S3: Innovative Preparation of High-Solids Soy Milk We select high-protein soybean varieties that have undergone rigorous screening. The selected soybeans are thoroughly washed to remove surface impurities and dust, and then soaked according to traditional processes. During the soaking process, we precisely control factors such as soaking time, water temperature, and water quality to ensure that the soybeans fully absorb water and swell, preparing them for the subsequent grinding process. Soaked soybeans are finely ground using grinding equipment. During the grinding process, grinding parameters such as the gap between the grinding discs and the grinding speed are optimized to ensure that the nutrients such as protein in the soybeans are fully released. Highly efficient separation equipment is used to separate soybean pulp from ground soybean milk. Various parameters during the separation process are strictly controlled to ensure that the separated soybean milk has a high solids content. The key control point is to accurately control the solids content of the soybean milk at 10-12%, which can provide enough soybean protein for subsequent fusion with highland barley gel base material, help to build a strong network structure, and improve the quality and stability of the product. S4: Steady-state fusion and ultra-high pressure homogenization The barley-soybean protein composite gel base from step S2 and the high-solids soy milk from step S3 are mixed according to the optimal nutritional and taste ratio of barley to soybean dry matter of 25:75. Mixing equipment is used during the mixing process to ensure that the two raw materials are fully and evenly mixed together. The mixed slurry is homogenized using an ultra-high pressure homogenizer, with the pressure precisely controlled at 100-150 MPa. Under ultra-high pressure, the barley component in the slurry and the soy milk can achieve uniform mixing at the molecular level, completely breaking down any possible gel particles and making the slurry more delicate and uniform. S5: Plastering and gel strengthening After boiling the homogenized slurry, it is quickly cooled to a suitable coagulation temperature (82-85℃). A coagulant composed of gluconate-δ-lactone (GDL) and gypsum is used for coagulation. The coagulant can give full play to the advantages of each of them. GDL can provide a mild acidic environment, which is conducive to the slow and uniform formation of the gel network, while gypsum can enhance the hardness and stability of the gel. During the coagulation process, the amount and speed of coagulant addition are precisely controlled to ensure optimal coagulation results. After coagulation, the soy milk is quickly poured into a specially designed molding box to provide a good environment for subsequent cooling and gel formation. Immediately place the soy milk injected into the molding box onto the oscillating cooling device, and slowly oscillate and cool the soy curd from 85°C to 60°C within 30 minutes. During the oscillating cooling process, the oscillating device can apply force evenly to the soy curd to prevent the gel network from shrinking too quickly, while also removing some water and maintaining the looseness of the gel structure. The slow cooling process allows protein molecules ample time to fold and cross-link, forming a denser and more elastic gel structure. This step is key to achieving the product's elasticity target of >3.5mm. By precisely controlling the cooling rate and oscillation parameters, we can ensure that the product reaches the ideal elasticity index, bringing consumers a better taste experience. S6: Compression molding and sterilization The reinforced gel is placed in a specially designed pressing device, and the pressure and time are precisely controlled according to the product specifications and requirements. Through reasonable pressure and time control, the product with the target moisture content can be obtained, so that the texture and taste of the product reach the best state. Pasteurization or high-pressure sterilization (HPP) is used to sterilize products while preserving their nutrition and flavor; high-pressure sterilization uses high pressure to destroy the cell structure of microorganisms, thus achieving sterilization. Based on the characteristics of the product and market demand, we flexibly select appropriate sterilization technologies to ensure the microbial safety of the product while extending its shelf life, thus providing consumers with safer, healthier, and tastier products.

[0022] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A process for making a barley bean curd, characterized by, Includes the following steps: S1: Precise screening and deep pretreatment of barley raw materials; S2: Targeted enzymatic hydrolysis and microencapsulation of barley components; S3: Preparation of high-solids soy milk; S4: Stabilization and ultra-high pressure homogenization of barley gel base material and high-solids soy milk; S5: Spot coagulation and gel strengthening; S6: Compression molding and sterilization.

2. The process for making highland barley tofu according to claim 1, characterized in that, Step S1 includes: a: Screening for specific highland barley varieties with protein content ≥12% and β-glucan content ≥6%; b: After cleaning and removing impurities from the barley grains, germinate them for 24-36 hours at a temperature of 28℃ and a humidity of 90%. c: Baking the germinated barley at a low temperature of 60-70℃; d: The roasted barley is ultra-finely pulverized to achieve a barley flour particle size of D90≤15μm.

3. The process for making highland barley tofu according to claim 1, characterized in that, Step S2 includes: a: Mix ultrafine highland barley powder with water in a ratio of 1:8 to make pulp, and adjust the pH and temperature to the optimal range of action of the compound enzyme; b: Add a complex enzyme containing β-glucanase and cellulase for targeted enzymatic hydrolysis. By monitoring the viscosity in real time, the reaction is terminated when the viscosity drops to 40%-50% of the initial value. c: After enzyme inactivation, soy protein isolate powder is added at 50℃ for microencapsulation, wherein the ratio of soy protein isolate to barley solids is 1:

2.

4. The process for making highland barley tofu according to claim 1, characterized in that, In step S3, the solids content of the final soy milk is precisely controlled between 10% and 12% by controlling the grinding and separation parameters.

5. The process for making highland barley tofu according to claim 1, characterized in that, The S4 step includes: a: Mix the highland barley-soybean protein composite gel base obtained in step S2 with the high solids soybean milk obtained in step S3 at a ratio of highland barley to soybean dry matter of 25:75; b: The mixed slurry is subjected to ultra-high pressure homogenization at a pressure of 100-150MPa.

6. The process for making highland barley tofu according to claim 1, characterized in that, Step S5 includes: a: After the homogenized slurry is boiled and cooled to 82-85℃, a coagulant made of gluconate-δ-lactone and gypsum is used for slurry application. b: After coagulation, the soy milk is slowly cooled from 85℃ to 60℃ within 30 minutes by shaking and cooling to make the finished product elasticity >3.5mm.

7. The process for making highland barley tofu according to claim 6, characterized in that, The oscillation cooling process is carried out on a specially designed oscillation cooling device, and the oscillation parameters are controlled to promote the formation and stabilization of the gel network.

8. The process for making highland barley tofu according to claim 1, characterized in that, The sterilization process in step S6 employs ultra-high pressure cold sterilization technology.

9. The process for making highland barley tofu according to claim 1, characterized in that, The dry matter ratio of highland barley to soybeans is 25:75, and the product elasticity is >3.5mm.

10. The barley tofu production process according to claim 1 and claim 9, characterized in that, The barley component exists as a microencapsulated complex formed by enzymatically modified medium- and short-chain β-glucan and soybean protein.

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