Method for preparing germinated brown rice from rice in large scale

Abstract

The invention discloses a large-scale method for preparing germinated brown rice from rice, relates to the technical field of germinated brown rice preparation, and aims to solve the problem that the mass production efficiency and the finished product quality are difficult to consider in the existing brown rice germination and rice germination technologies. The method comprises the steps of graded magnetic separation and purification of raw materials, ozone sterilization and residue removal, partitioned flow-controlled precise soaking, draining and sorting of empty shells, layered temperature-controlled pulse oxygen supply germination, slow cooling and tempering, temperature-controlled static drying, low-temperature temporary storage, two-stage flexible rice hulling and pre-cooling nitrogen-filled packaging. The water absorption and oxygen absorption consistency of the rice is improved through partitioned soaking and layered germination regulation, and the content of gamma-aminobutyric acid in a finished product exceeds 40 mg / 100 g; the two-stage flexible rice hulling enables the germ integrity rate to be fully improved, and stable large-scale production of the high-quality germinated brown rice is achieved.

Description

Technical Field

[0001] This invention relates to the field of germinated brown rice production technology, specifically a method for large-scale production of germinated brown rice from paddy. Background Technology

[0002] Against the backdrop of the upgrading of healthy staple food consumption, sprouted brown rice, due to its rich content of gamma-aminobutyric acid (GABA), soluble dietary fiber, and active enzymes, has become a core category to replace ordinary refined rice. The market demand for large-scale, high-quality sprouted brown rice is growing at an average annual rate of over 35%. Currently, the mainstream production technologies in the industry are divided into two categories: "brown rice sprouting" and "paddy rice sprouting." However, both existing technologies have systemic defects that are difficult to overcome, making it impossible to balance mass production efficiency and finished product quality, which seriously restricts the development of the industry.

[0003] Existing brown rice germination technology faces three major problems during processing because the husk of the brown rice has been removed: First, the direct exposure of the endosperm leads to a high risk of microbial contamination, with the rate of E. coli exceeding the standard in the finished product reaching over 25%, and it is prone to mold growth during storage; Second, the brown rice absorbs water too quickly, with a germination cycle of only 24-36 hours, resulting in insufficient activation of key enzyme systems such as glutamate decarboxylase, and the finished product's GABA content is generally below 120mg / 1000g, indicating insufficient nutrient density; Third, large-scale production requires frequent manual water replenishment and humidity control, with an average daily output of only 400kg per person, resulting in low efficiency and large batch-to-batch variations.

[0004] While existing rice germination technology addresses some of the pain points of brown rice germination, it still suffers from several technical shortcomings: First, raw material selection relies solely on a simple destoner, failing to separate shriveled grains (5%-8%) and metallic impurities (such as harvested nails and wires). These impurities can clog the air vents of the soaking equipment and become breeding grounds for mold, increasing the germination contamination rate to 18%. Second, the soaking process uses a single air pump, concentrating air bubbles in the middle of the tank. The dissolved oxygen concentration in the bottom layer of rice is only 3-4 mg / L, a difference of 6 mg / L from the surface, resulting in uneven water and oxygen absorption by the rice, leading to a germination uniformity of less than 65%. Furthermore, floating impurities (empty shells, damaged grains) are only separated by a single air pump. The following issues were identified: First, the side overflow cleaning resulted in a residue rate exceeding 10%. Second, the germination chamber used overall temperature control, with a temperature difference of 4-6℃ between the upper and lower layers of rice placed in layers, leading to a chest breakage rate fluctuating between 60% and 85%, and a difference in sprout length exceeding 2.5mm, making standardization impossible. Third, the drying process used traditional static drying, resulting in uneven hot air distribution and local temperatures easily exceeding 50℃, causing a loss of more than 30% of GABA. Furthermore, the moisture content of the dried rice fluctuated by ±1.2%, making it prone to breakage during subsequent hulling. Fourth, the hulling process used rigid rubber roller equipment, resulting in high mechanical impact and a sprout damage rate as high as 35%, directly reducing nutritional value. Fifth, the connection between various process steps relied on manual transfer, which was not only inefficient but also prone to rice wear due to manual operation.

[0005] Furthermore, existing technologies lack designs for shaping and protecting germinated sprouts after germination and for temporary storage after drying, resulting in a sprout shedding rate exceeding 15% and a shortened storage period of 3-6 months. In summary, existing processes have significant shortcomings in raw material purification, environmental control, nutrient retention, equipment synergy, and process integration. There is an urgent need for a large-scale method with innovative process design to overcome industry technical bottlenecks and achieve stable mass production of high-quality germinated brown rice. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a method for large-scale production of germinated brown rice from paddy rice, thus solving the problems mentioned in the background section.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a method for large-scale production of germinated brown rice from paddy rice, comprising the following steps:

[0008] S1. Use a rice grain separator to separate impurities such as imperfect grains and stems and leaves from the rice grains, and then temporarily store them after magnetic separation;

[0009] S2. The temporarily stored rice is transported to the soaking tank and sterilized using ozone solution;

[0010] S3. After disinfection, the rice continues to soak in the zoned controlled flow soaking tank. During the soaking process, the dissolved oxygen concentration in the soaking water is maintained at a stable level through the aeration device. The buoyancy of the bubbles generated by the aeration device drives the rice to tumble, which has the effect of cleaning the rice. The soaking water is circulated and replaced in a timely manner until the water is clean and free of turbidity. At the same time, suspended impurities are removed by the circulating filtration system. The pH value of the soaking water is adjusted to 6.0-7.5 in real time. Soaking is stopped when the rice absorbs 24%-40% of its own weight in water.

[0011] S4. Drain the soaked rice and keep it moist, then transport it to the germination room to germinate.

[0012] S5. Heat the germination chamber to slowly raise the temperature to 35°C. Circulate oxygen and heat through the airflow device to maintain a relative humidity of ≥82%. When the rice grain breakage rate is ≥85%, lower the temperature of the germination chamber to 20-30°C until the sprout or root length reaches about 1 / 2 of the grain length, then stop heating for germination.

[0013] S6. Turn the sprouted rice over to cool it down until it is the same temperature as the outside temperature.

[0014] S7. The sprouted grains after slow cooling are dried using a high-efficiency batch dryer. Except for the two tempering layers at the top (air-proof layers, which can prevent the circulating hot air from short-circuiting and reducing the drying efficiency after the material is full) and the bottom feeder layer, the middle part of the dryer is a drying section. The temperature of the main drying section is ≤45℃, and the final moisture content of the sprouted grains is dried to below 13.5%.

[0015] S8. Store the dried sprouted grains in a low-temperature environment until they are dehulled and processed into coarse grains.

[0016] S9. The stored dried germinated rice is processed through a variable frequency rice huller with adjustable speed and pressure to remove the husk using a flexible processing method. After being processed by gravity sieve and grading sieve, brown rice and broken brown rice and debris are separated to ensure that the germ integrity rate is ≥98%.

[0017] S10. After the selected germinated brown rice is sterilized by ultraviolet light, it is quantitatively packaged, vacuum treated, and then sealed.

[0018] Optionally, the partitioned flow control soaking tank in step S3 is divided into an inlet zone, a soaking zone, and a separation zone for impurities such as stems and leaves. Each zone is separated by a guide plate, and the bottom of the guide plate is provided with an overflow port. The bottom surface of the impurity separation zone is lower than that of the soaking zone. Floating impurities are collected by the water flow to the impurity separation zone and flow out from the top impurity tank. A filter screen is provided at the end of the impurity tank to recover residual rice.

[0019] Optionally, in step S4, the rice grains are drained of excess water using a sieve and kept moist. A water collection trough is set below the sieve, and the collected soaking water is filtered and returned to the soaking tank. The buoyancy of the soaking water is used to separate shriveled grains and impurities such as stems and leaves, so that the removal rate of empty grains is ≥99%. The drained rice grains are then transferred to the germination chamber.

[0020] Optionally, the germination chamber in step S5 is equipped with a layered rack, on which a temperature sensor is installed and connected to a thermostat; in the early stage of germination, the thermostat is set to a temperature of 35-45℃ for circulating heating and oxygenation; when the rice grain breakage rate is ≥85%, the thermostat lowers the temperature to 20-30℃, maintaining an indoor oxygen concentration of ≥20% during this stage; a nebulizer is installed on the top of the germination chamber, and the atomized water is pure water to maintain an indoor relative humidity of ≥82%.

[0021] Optionally, the high-efficiency batch grain dryer described in step S7 adopts a mixed-flow drying structure (the drying section has angled pipe air ducts, unlike the screen form of ordinary circulating dryers). Except for the two top tempering layers (air-proof layers, which can prevent short-circuiting of circulating drying hot air and reduce drying efficiency after the material is full) and the bottom feeder layer, the middle is all drying section; the dryer tower is divided into two independent towers, left and right, with a space between the two towers. This space is sealed front, back, top, and bottom to form a hot air box for drying; the outside of the tower is sealed with heat insulation board, forming a sealed heat-insulated cavity for circulating exhaust air. The heat-insulated cavity and the outside of the drying tower have spaces in three directions, allowing the exhaust air that has undergone heat exchange to enter the next drying cycle or be partially discharged to the ash room; the external hot air enters the lower part of the intermediate hot air box through the blower, is drawn in by the circulating axial flow fan and sent into the intermediate hot air box, and blown into the drying towers on both sides. After heat exchange with the material inside the tower through the angled air duct, the exhaust air is discharged from the outside of the two tower bodies. Part of the discharged humid exhaust air is discharged outside the dryer, while another part is drawn in by the circulating axial flow fan and mixed with clean, high-temperature external hot air to form an internal circulating hot air cycle to continue drying the grains. The remaining humid exhaust air enters the external heat exchanger or hot air furnace through the return air duct for heating, forming an external circulating hot air cycle to re-enter the next drying heat exchange cycle. The grains in the drying towers on both sides of the chamber dryer are circulated alternately during the drying process; that is, circulation on one side of the tower stops after a certain period, and then circulation on the other side begins, ensuring that the grains in the top tempering layer and the feeder layer are fully and evenly dried. Compared with ordinary circulating dryers, this dryer reduces the number of cycles by half, resulting in higher drying efficiency. The drying rate is 50% to 80% higher than that of ordinary dryers, and the increase in grain breakage rate and cracking rate is far lower than the national standard, resulting in superior drying quality.

[0022] Optionally, the temperature of the low-temperature environment in step S8 is controlled at 10-15℃ and the relative humidity is controlled within 60%; the germinated grains are stored in this low-temperature and low-humidity environment for no more than 6 months, during which the moisture content of the germinated grains is tested regularly to ensure that it does not exceed 13.5%.

[0023] Optionally, the rice huller described in step S9 uses a variable frequency dual motor, with each motor's speed independently controlled by a frequency converter. The rice husk is removed by a flexible extrusion method through machine differential speed adjustment and tight roller air pressure adjustment. After rice husk separation and grading sieve treatment, the rice husk residue rate is ≤0.5%, and the germ integrity rate is ≥98%.

[0024] Optionally, in step S10, ultraviolet light is used to disinfect and sterilize the germinated brown rice, which is then dispensed using a quantitative filling machine, vacuum-treated, and sealed.

[0025] This invention provides a method for large-scale production of germinated brown rice from paddy rice, which has the following beneficial effects:

[0026] This invention, which uses rice to produce germinated brown rice on a large scale, breaks through existing technical bottlenecks through the coordinated use of equipment and process design in 10 innovative technological steps, from raw material purification, germination control, drying protection to finished product packaging, significantly improving the efficiency of large-scale production and the quality of finished products. In the raw material processing stage, the integrated design of grading and screening, magnetic separation, and photoelectric detection, combined with ozone pretreatment, reduces the microbial contamination rate from 18% in existing technologies to below 3%, while preventing metal impurities from clogging the equipment. The zoned flow control and circulating filtration system in the soaking stage, combined with precise dissolved oxygen regulation, lays the foundation for uniform germination. The layered temperature control and pulsed oxygen supply in the germination stage precisely match the physiological needs of different germination stages of rice, controlling the difference in sprout length to within 1mm, and achieving a finished product GABA content exceeding 40mg / 100g. The slow cooling and conditioning design after germination effectively prevents sprout detachment. The segmented temperature control and counter-current hot air circulation in the drying stage strictly control the main drying temperature to ≤45℃, with post-drying rice moisture fluctuations within ±0.3%, providing stable raw materials for hulling processing. The low-temperature temporary storage stage prevents moisture regain. The dual-stage flexible hulling design, through the synergy of rubber rollers and silicone scrapers, directly ensures nutritional value. Finally, low-temperature pre-cooling and vacuum packaging slow down the oxidation rate of nutrients in the finished product, extending the shelf life from 3-6 months to 12 months. Detailed Implementation

[0027] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0028] A method for large-scale production of germinated brown rice from paddy rice includes the following specific steps:

[0029] S1. A rice concentrator is used to separate shriveled grains with a diameter <2.6mm and broken grains with a diameter >3.3mm from the rice. The graded rice is then temporarily stored after magnetic separation.

[0030] S2. After the temporarily stored rice is transported to the soaking tank, it is sterilized and disinfected with ozone solution.

[0031] S3. Soak the rice in a zoned flow-controlled soaking tank. During the soaking process, an aeration device is used to ensure a stable dissolved oxygen concentration in the soaking zone. A circulating filtration system is used to remove suspended impurities from the water, and the pH of the soaking solution is adjusted in real time to 6.0-7.5. The soaking time is controlled according to the average daily temperature to ensure that the moisture content of the rice reaches 36%-41%. The zoned flow-controlled soaking tank is divided into an inlet zone, a soaking zone, and a separation zone for stems, leaves, and other impurities. Each zone is separated by a guide plate, and an overflow port is provided at the bottom of the guide plate. The bottom of the impurity separation zone is lower than that of the soaking zone. Floating impurities are collected by the water flow to the impurity separation zone and flow out from the top impurity tank. A filter screen is installed at the end of the impurity tank to collect residual rice.

[0032] S4. After soaking, drain the surface water of the rice and separate the remaining empty husks. The drained rice is temporarily stored and drained using a vibrating screen to ensure that the surface moisture content of the drained rice is ≤15%. A water collection tank is set under the vibrating screen, and the collected soaking water is filtered and returned to the soaking tank. An air classifier is installed at the outlet of the vibrating screen to separate the remaining empty husks, so that the empty husk removal rate is ≥99%. The drained rice is temporarily stored in a container with ventilation holes.

[0033] S5. The temporarily stored rice is transported to a germination dark chamber. During the early germination stage, the temperature of the germination dark chamber is controlled, and oxygen is intermittently supplied to maintain a relative humidity ≥82%. When the rice bud break rate is ≥85%, the temperature of the germination dark chamber is reduced and maintained until the sprout or root length reaches 1 / 2-1 of the grain length, at which point germination stops. The germination dark chamber is equipped with tiered shelves, on which temperature sensors are installed and connected to a thermostat. During the early germination stage, the thermostat is set to 29-33℃, and oxygen is supplied every 3-4 hours for 35-45 minutes each time, maintaining an indoor oxygen concentration of 23%-26%. When the rice bud break rate is ≥85%, the thermostat is lowered to 16-26℃ and maintained for 7-9 hours, during which time the indoor oxygen concentration is maintained at 21%-23%. A misting device is installed at the top of the germination dark chamber, using pure water to maintain a relative humidity ≥82%.

[0034] S6. Slowly cool the sprouted rice until it is the same temperature as the outside temperature, turning the rice over during the slow cooling process;

[0035] S7. The slow-cooled rice is dried using a high-efficiency batch-type chamber dryer. The drying process is divided into a preheating section, a main drying section, and a cooling section. The temperature of the main drying section is ≤45℃, and the rice is dried until the final moisture content is reduced to below 13.5%. The preheating section, main drying section, and cooling section of the segmented temperature-controlled chamber static dryer are equipped with heat-insulating partitions, and the bottom of the partitions has ventilation openings. The rice is evenly spread on the mesh trays of the dryer. The temperature of the preheating section is controlled at 36-41℃ and the hot air velocity is 0.6m / s, and the preheating time is 1.2-1.5h. The main drying section uses counter-current hot air circulation, with a hot air velocity of 0.7-0.9m / s, and the drying time is 4.2-5.2h. The temperature of the cooling section is controlled at 26-31℃ and the hot air velocity is 0.5m / s, and the cooling time is 1.3-1.6h.

[0036] High-efficiency chamber-type batch grain dryer; The chamber dryer adopts a mixed-flow drying structure (the drying section has angular pipe air ducts, which is different from the screen form of ordinary circulating dryers). Except for the two top tempering layers (air-proof layers, which can prevent the hot air of circulating drying from short-circuiting and causing low drying efficiency after the material is full) and the bottom feeder layer, the middle section is all drying section.

[0037] The chamber dryer tower is divided into two independent towers, left and right, with a space between them. This space is sealed front to back and top to bottom to form a hot air box for drying. The outside of the tower is sealed with heat insulation panels, forming a sealed, insulated cavity for recycling the exhaust air. This cavity has spaces on three sides to allow the exhaust air, after heat exchange, to pass through this space into the next drying cycle or be partially discharged into the ash chamber. External hot air enters the lower part of the intermediate hot air box through a blower, is drawn in by a circulating axial fan, and is then blown into the intermediate hot air box and into the drying towers on both sides. It exchanges heat with the material inside the tower through angled ducts and is discharged from the outer sides of the two towers. Part of the discharged humid exhaust air is discharged outside the dryer, and part is reused. The freshly drawn-in axial flow fan mixes with clean, high-temperature hot air from the outside to form an internal circulating hot air cycle, continuing to dry the grains. Another portion of the moist tail air enters the external heat exchanger or hot air furnace through a return duct, forming an external circulating hot air cycle, which then re-enters the next drying heat exchange cycle, repeating continuously. In the chamber dryer, the grains in the drying towers on both sides circulate alternately during the drying process. That is, after circulating on one side of the tower for a certain period, circulation stops, and then the other side begins circulating. This ensures that the grains in the top tempering layer and the feeder layer are dried thoroughly and evenly, reducing the number of cycles by half compared to ordinary circulating dryers. The drying efficiency is high, with a drying rate 50% to 80% higher than ordinary dryers. The fewer cycles result in a much lower increase in grain breakage and cracking rates compared to national standards, leading to high-quality drying.

[0038] S8. After drying, temporarily store the rice in a low-temperature environment, with the temperature controlled at 10-15℃ and the relative humidity controlled at 52%-62%. The rice is stored in stainless steel hoppers with ventilation holes, and the hoppers are spaced apart to ensure air circulation. The storage time shall not exceed 72 hours. During the storage period, the moisture content of the rice shall be tested regularly to ensure that the moisture fluctuation is ≤±0.3%.

[0039] S9. Remove the husks from the temporarily stored rice using a flexible processing method, ensuring that the germ integrity rate is ≥96%, and remove the husks and broken rice fragments. The first stage of the rice huller uses food-grade nitrile rubber rollers to remove the husks through flexible extrusion; the second stage uses medical-grade silicone scrapers to remove residual husks through gentle scraping, ensuring that the husk residue rate is ≤0.5%; a germ integrity detector is installed at the outlet of the rice huller to monitor the germ integrity rate in real time.

[0040] The rice huller uses dual variable frequency motors, each with its own speed controlled by a frequency converter. Through machine differential speed adjustment, the tight roller air pressure is adjusted to flexibly extrude and remove the rice husks. After rice-coated rice and husk separation, the grading screen ensures that the rice husk residue rate is ≤0.5%. A germ integrity detector is installed at the rice huller outlet to monitor the germ integrity rate in real time.

[0041] S10. After the screened brown rice is sterilized by ultraviolet light, it is quantitatively packaged, vacuum treated, and then sealed.

[0042] Example 1: Based on a production environment with an average daily temperature of 20°C, large-scale production was carried out according to the method of the present invention. The specific operation is as follows:

[0043] (1) A rice selection machine is used to separate shriveled grains with a diameter of <2.6mm and broken grains with a diameter of >3.3mm by rotating at a constant speed of 18r / min. The graded rice is fed into a magnetic separator through a closed conveyor belt to remove metal impurities. The selected rice is temporarily stored in a stainless steel silo.

[0044] (2) The rice in the silo is fed into the ozone sterilizer by a screw conveyor (ozone concentration 80mg / m³, treatment time 15min); after sterilization, the residual ozone on the surface of the rice is separated by a cyclone separator, and the pretreated rice is transported to the zoned flow control soaking tank.

[0045] (3) The zoned flow control soaking tank is divided into an inlet zone, a soaking zone, and an impurity separation zone. Each zone is separated by an 80cm high guide plate, with a 6cm overflow port at the bottom of the guide plate. The soaking zone is connected to a microporous aeration disc via a GA-7.5 type vortex air pump to maintain a dissolved oxygen concentration of 9.5mg / L in the water. The bag filter is turned on to circulate the soaking water 4 times per hour to remove suspended impurities. The pH of the soaking solution is adjusted to 6.4 using a PHG-300 type online pH monitor. Due to the average daily temperature of 20℃, the soaking time is set to 68h, and samples are taken every 12h for testing. The final moisture content of the rice reaches 38%. The floating impurities collected in the impurity separation zone are filtered through a 100-mesh filter, and the residual rice recovery rate is 96.5%.

[0046] (4) After soaking, the rice is fed into a ZS-600 vibrating screen (2mm screen, 50Hz vibration frequency) by an elevator. After draining, the surface moisture content of the rice is reduced to 14%. The soaking water collected in the water collection tank below the vibrating screen is filtered by a filter and then returned to the soaking tank. The airflow separator (wind speed 5m / s) at the outlet of the vibrating screen separates the residual empty shells. The drained rice is temporarily stored in a plastic basket with ventilation holes.

[0047] (5) The rice grains are fed into the germination dark chamber by a low-speed elevator (16r / min); the temperature is set to 31℃ during the early germination period (0-45h), the oxygen supply system is started, and oxygen is supplied once every 3.5h for 40min each time to maintain the oxygen concentration in the room at 24.5%; the ultrasonic atomizer at the top of the dark chamber maintains a relative humidity of 85%; when the rice grains are sampled and the bud break rate reaches 88%, the temperature controller lowers the temperature to 21℃ and maintains it for 8h, during which the oxygen concentration is maintained at 22%; when the sprout length reaches 0.8 times the grain length, germination is stopped.

[0048] (6) Turn on the centrifugal ventilation fans on both sides of the germination dark chamber (wind speed 0.4m / s) to reduce the indoor temperature from 21℃ to 20℃ at a rate of 1℃ / h, with a slow cooling time of 5h; during the slow cooling process, the electric turning rod turns the rice once per hour to ensure uniform heat dissipation.

[0049] (7) The slow-cooled rice is fed into a high-efficiency batch grain dryer. The preheating section (2m), main drying section (4m), and cooling section (2m) inside the dryer are separated by a 5cm thick heat-insulating partition. A 0.5m² ventilation opening is provided at the bottom of the partition. The rice is evenly spread on a mesh tray. The temperature of the preheating section is 38℃, the hot air velocity is 0.6m / s, and the preheating time is 1.3h (the surface moisture content drops to 22%). The main drying section adopts counter-current hot air circulation, the temperature is 43℃, the hot air velocity is 0.8m / s, and the drying time is 4.7h. The temperature of the cooling section is 28℃, the hot air velocity is 0.5m / s, and the cooling time is 1.4h. Finally, the moisture content of the rice drops to 12.8%.

[0050] (8) The dried rice was sent to a low-temperature warehouse via a closed conveyor belt. The temperature inside the warehouse was 7°C and the relative humidity was 57%. The rice was stored in stainless steel hoppers with ventilation holes, with a spacing of 30cm between the hoppers. It was temporarily stored for 48 hours, during which the moisture content was tested every 24 hours, with a fluctuation of ±0.2%.

[0051] (9) The rice is fed into the rice huller by a low-speed elevator; the first stage is a food-grade nitrile rubber roller with a speed of 310 r / min and a distance of 3.0 mm between the two rollers, removing 85% of the rice husk; the second stage is a medical-grade silicone scraper with a contact pressure of 0.14 MPa, removing the remaining rice husk; the germ integrity tester at the rice huller outlet shows a germ integrity rate of 97.3%; the brown rice after hulling is fed into a vibrating screen, with a broken rice removal rate of 93.5%;

[0052] (10) The screened brown rice is sent to a low-temperature precooling machine at a precooling temperature of 12°C for 35 minutes. After precooling, it is packaged by a quantitative filling machine, filled with food-grade nitrogen, and heat-sealed.

[0053] Comparative Example 1: Existing "brown rice germination" technology uses brown rice as raw material, without grading, screening, or magnetic separation; the brown rice is directly sent to a soaking tank (without zoned flow control, no aeration device, unadjusted pH of the soaking solution, and dissolved oxygen concentration of 5 mg / L), soaked for 30 hours at an average daily temperature of 20℃, resulting in a paddy rice moisture content of 35%; after soaking, it is naturally drained (surface moisture content of 20%) without separating the empty husks; it is then sent to a germination chamber (overall temperature controlled at 28℃, continuous oxygen supply, and relative humidity of 80%), where it germinates for 36 hours; a traditional static dryer is used (temperature 50℃, drying for 3 hours), resulting in a final moisture content of 14%; the husks are removed using a single-stage rigid rubber roller huller; no pre-cooling is performed, and the rice is directly packaged using ordinary methods.

[0054] Comparative Example 2: Existing "rice germination" technology involves rice that is only screened by a destoner and directly sterilized with ozone; it is then placed in a conventional soaking tank (without circulating filtration, a single aeration device, dissolved oxygen concentration of 4 mg / L, and no pH adjustment) and soaked for 70 hours at an average daily temperature of 20°C until the moisture content is 40%; after soaking, it is drained by a vibrating screen (surface moisture content of 18%) without airflow sorting; the germination chamber uses a controlled temperature of 30°C, with oxygen supplied once every 6 hours (30 minutes each time), and a relative humidity of 78%; drying is done using a traditional static dryer (temperature 52°C, drying for 4 hours); the rice is then hulled using a single-stage rigid rubber roller huller; and finally packaged using standard methods.

[0055] Comparative Analysis of Examples and Comparative Cases index Example 1 (Invention) Comparative Example 1 (existing brown rice germinated) Comparative Example 2 (existing rice grains sprouting) Impurity removal rate 99.6% Not detected (not classified) 92.5% (stones removed only) Microbial contamination rate 2.1% 26.3% 17.8% Germination uniformity 98% 58% 62% GABA content of finished product (mg / 100g) 56 16 14 Embryo integrity rate 97.3% 65.2% 63.2% bud shedding rate 1.8% 12.3% 16.5%

[0056] As can be seen from the above comparison, the present invention significantly solves the problems of high impurity residue, serious microbial contamination, low nutrient content and poor production efficiency in the prior art by purifying raw materials, controlling the environment precisely, processing flexibly and connecting with automation, and achieves a synergistic improvement in scale and quality.

[0057] 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 method for large-scale production of germinated brown rice from paddy rice, characterized in that, Includes the following steps: S1. Use a rice grain separator to separate impurities such as imperfect grains and stems and leaves from the rice grains, and then temporarily store them after magnetic separation; S2. The temporarily stored rice is transported to the soaking tank and sterilized using ozone solution; S3. After disinfection, the rice continues to soak in the zoned controlled flow soaking tank. During the soaking process, the dissolved oxygen concentration in the soaking water is maintained at a stable level through the aeration device. The buoyancy of the bubbles generated by the aeration device drives the rice to tumble, which has the effect of cleaning the rice. The soaking water is circulated and replaced in a timely manner until the water is clean and free of turbidity. At the same time, suspended impurities are removed by the circulating filtration system. The pH value of the soaking water is adjusted to 6.0-7.5 in real time. Soaking is stopped when the rice absorbs 24%-40% of its own weight in water. S4. Drain the soaked rice and keep it moist, then transport it to the germination room to germinate. S5. Heat the germination chamber to slowly raise the temperature to 35-45℃. Circulate oxygen and heat through the airflow device to maintain a relative humidity of ≥82%. When the rice grain breakage rate is ≥85%, lower the temperature of the germination chamber to 20-30℃ until the sprout or root length reaches about 1 / 2 of the grain length, then stop heating for germination. S6. Turn the sprouted rice over to cool it down until it is the same temperature as the outside temperature. S7. The sprouted grains are dried and cooled using a high-efficiency batch dryer. The dryer has two layers of tempering layer at the top, a slow feeder layer at the bottom, and a drying section in the middle. The temperature of the main drying section is ≤45℃, and the final moisture content of the sprouted grains is dried to below 13.5%. S8. Store the dried sprouted grains in a low-temperature environment until they are dehulled and processed into coarse grains. S9. The stored dried germinated rice is processed through a variable frequency rice huller with adjustable speed and pressure to remove the husk using a flexible processing method. After being processed by gravity sieve and grading sieve, brown rice and broken brown rice and debris are separated to ensure that the germ integrity rate is ≥98%. S10. After the selected germinated brown rice is sterilized by ultraviolet light, it is quantitatively packaged, vacuum treated, and then sealed.

2. The method according to claim 1, characterized in that, The partitioned flow control soaking tank described in step S3 is divided into an inlet zone, a soaking zone, and a separation zone for impurities such as stems and leaves. Each zone is separated by a guide plate, and the bottom of the guide plate is provided with an overflow port. The bottom surface of the impurity separation zone is lower than that of the soaking zone. Floating impurities are collected by the water flow to the impurity separation zone and flow out from the top impurity tank. A filter screen is provided at the end of the impurity tank to recover residual rice.

3. The method according to claim 1, characterized in that, In step S4, the rice grains are drained of excess water using a sieve and kept moist. A water collection trough is set below the sieve, and the collected soaking water is filtered and returned to the soaking tank. The buoyancy of the soaking water is used to separate shriveled grains and impurities such as stems and leaves, so that the removal rate of empty grains is ≥99%. The drained rice grains are then transferred to the germination chamber.

4. The method according to claim 1, characterized in that, The germination chamber described in step S5 is equipped with a layered shelf, on which a temperature sensor is installed and connected to a thermostat. In the early stage of germination, the thermostat is set to 35°C for circulating heating and oxygenation. When the rice grain breakage rate is ≥85%, the thermostat lowers the temperature to 20-30°C, maintaining an indoor oxygen concentration of ≥20% during this stage. The top of the germination chamber is equipped with an atomizer, which atomizes pure water to maintain an indoor relative humidity of ≥82%.

5. The method according to claim 1, characterized in that, The high-efficiency batch grain dryer described in step S7 adopts a mixed-flow drying structure (the drying section has angled pipe air ducts, unlike the screen form of ordinary circulating dryers). Except for the two top tempering layers (air-proof layers, which can prevent short-circuiting of circulating drying hot air and reduce drying efficiency after the material is full) and the bottom feeder layer, the middle is the drying section. The dryer tower is divided into two independent towers, left and right, with a space between them. This space is sealed front, back, top, and bottom to form a hot air box for drying. The outside of the tower is sealed with heat insulation board, forming a sealed heat-insulated cavity for circulating exhaust air. The heat-insulated cavity has space in three directions with the outside of the drying tower, allowing the exhaust air that has undergone heat exchange to enter the next drying cycle or be partially discharged to the ash room. External hot air enters the lower part of the middle hot air box through the blower, is drawn in by the circulating axial flow fan and sent into the middle hot air box, and blown into the drying towers on both sides, passing through the angled pipe air ducts. After heat exchange with the material inside the tower via the duct, the exhaust air is discharged from the outside of the two tower bodies. Part of the discharged humid exhaust air is discharged outside the dryer, while another part is drawn in by the circulating axial flow fan and mixed with clean, high-temperature external hot air to form an internal circulating hot air cycle to continue drying the grains. The remaining humid exhaust air enters the external heat exchanger or hot air furnace through the return duct for heating, forming an external circulating hot air cycle to re-enter the next drying heat exchange cycle. The grains in the drying towers on both sides of the chamber dryer are circulated alternately during the drying process; that is, circulation on one side of the tower stops after a certain time, and then circulation on the other side begins, ensuring that the grains in the top tempering layer and the feeder layer are fully and evenly dried. Compared to ordinary circulating dryers, this dryer reduces the number of cycles by half, resulting in higher drying efficiency. The drying rate is 50% to 80% higher than that of ordinary dryers, and the increase in grain breakage rate and cracking rate is far lower than the national standard, resulting in superior drying quality.

6. The method according to claim 1, characterized in that, The temperature of the low-temperature environment mentioned in step S8 is controlled at 10-15℃ and the relative humidity is controlled within 60%. The germinated grains are stored in this low-temperature and low-humidity environment for no more than 6 months. During this period, the moisture content of the germinated grains is tested regularly to ensure that it does not exceed 13.5%.

7. The method according to claim 1, characterized in that, The rice huller described in step S9 uses a variable frequency dual motor. By adjusting the speed and pressure of the two rubber rollers of each rice huller, an ideal linear speed difference and pressure are obtained to remove the rice husks with a gentle rubbing and pressing motion. The speed of each motor is independently controlled by a frequency converter. The rice husks are removed by a gentle extrusion method through machine differential speed adjustment and tight roller air pressure adjustment. After separation of rice husks and grading, the rice husk residue rate is ≤0.5%, and the germ integrity rate is ≥98%.

8. The method according to claim 1, characterized in that, In step S10, ultraviolet light is used to disinfect and sterilize the germinated brown rice, which is then dispensed using a quantitative filling machine, vacuum treated, and then sealed.