Device and method for measuring starch content of finished feed product
By combining the integrated crushing and hydrolysis components with the screw rod, rotating block, and magnet anti-clogging plate, the problem of low starch content measurement efficiency in existing devices is solved, achieving efficient and stable starch content detection.
Patent Information
- Application Number
- CN202511282742.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-09
- Publication Date
- 2025-12-30
AI Technical Summary
Existing equipment has low efficiency in measuring the starch content of finished feed products, and suffers from problems such as uneven hydrolysis reaction and easy blockage of the discharge port after crushing, which leads to a longer testing process and cannot meet the requirements of efficient testing.
The integrated crushing and hydrolysis reaction components, combined with screw lifting, rotating block crushing, magnetic anti-clogging plate and stirring rod mixing, achieve efficient crushing and uniform hydrolysis of feed, and calculate starch content by optical rotation measurement.
It significantly improves the efficiency of starch content determination process, avoids feed blockage, improves crushing efficiency and the uniformity of hydrolysis reaction, and shortens the testing cycle.
Smart Images
Figure CN121231384A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of feed testing technology, specifically to an apparatus and method for determining the starch content of finished feed products. Background Technology
[0002] Existing devices for determining the starch content of finished feed products suffer from low efficiency in practical applications. The existing hydrolysis reaction and crushing components are designed separately, increasing the feed transfer process and prolonging the overall testing workflow. Furthermore, issues such as feed clogging the discharge port after crushing and uneven mixing in the hydrolysis reaction affecting efficiency arise. These factors collectively prevent existing devices from efficiently determining the starch content of finished feed products, failing to meet the efficiency requirements of the feed testing field.
[0003] Based on this, an apparatus and method for determining the starch content of finished feed products are now provided, which can eliminate the drawbacks of existing apparatuses. Summary of the Invention
[0004] The purpose of this invention is to provide an apparatus and method for determining the starch content of finished feed products, so as to solve the problem of low efficiency in existing apparatuses for measuring starch content in the prior art.
[0005] To achieve the above objectives, the present invention provides the following technical solution:
[0006] An apparatus for determining the starch content of finished feed includes a polarimeter, a cyclotron tube, a reaction chamber, a lifting chamber, and a crushing chamber. The reaction chamber contains a hydrolysis reaction assembly to improve the efficiency of the feed hydrolysis reaction. A crushing chamber is located on the upper surface of the reaction chamber, containing a crushing assembly for crushing the feed to a predetermined particle size. A guide pipe with a valve connects the lifting chamber and the crushing chamber. A lifting assembly is located in the lifting chamber to lift and transport the feed to the crushing chamber. The cyclotron tube holds the products of the feed hydrolysis reaction. The polarimeter measures the optical rotation of the products after the feed hydrolysis reaction. The starch content in the finished feed is calculated based on the optical rotation and known coefficients. A water inlet with a valve is located on the upper surface of the reaction chamber for injecting dilute hydrochloric acid into the reaction chamber.
[0007] Based on the above technical solutions, the present invention also provides the following optional technical solutions:
[0008] In one alternative embodiment: the lifting assembly includes a screw rod, a second motor, and a feed hopper; the side wall of the lifting box is connected to the feed hopper via a feed pipe; the lower surface of the lifting box is fixedly connected to the second motor via a bracket; the lifting box is connected to the screw rod via a bearing; and the screw rod is connected to the output end of the second motor.
[0009] In one alternative embodiment: the crushing assembly includes a first motor, a rotating block, and a rotating shaft; a crushing box is fixedly connected to the upper surface of the reaction chamber; the first motor is installed on the upper surface of the crushing box; the rotating shaft is connected to the crushing box via bearings; a rotating block is fixedly connected to the rotating shaft; the rotating block has a trapezoidal cross-section; several crushing blocks are installed at the bottom of the rotating block; the crushing box has a trapezoidal cross-section; and a feed inlet is provided at the connection between the crushing box and the reaction chamber.
[0010] In one alternative: two symmetrical guide rails are fixedly connected to the inner wall of the crushing box, and a first slider is slidably connected to the inner side wall of the guide rail. The two first sliders are fixedly connected to a lifting ring through a bracket. Two symmetrical second sliders are fixedly connected to the inner wall of the lifting ring. An arc-shaped groove is opened on the circumference of the rotating block, and the second slider is slidably connected to the inner wall of the arc-shaped groove. An anti-blocking plate is provided below the lifting ring.
[0011] In one alternative: two magnets are embedded in the rotating block, a lifting plate is fixedly connected to the lower surface of the lifting ring, the lifting plate has an anti-blocking groove, the anti-blocking plate is slidably connected to the inner wall of the anti-blocking groove, a spring is fixedly connected between the anti-blocking plate and the inner wall of the anti-blocking groove, and the anti-blocking plate is made of ferromagnetic material.
[0012] In one alternative: a stop block is fixedly connected to the upper surface of the lifting ring.
[0013] In one alternative embodiment: the hydrolysis reaction assembly includes a stirring rod, a heating coil, and a heating box; the rotating shaft extends through into the reaction box; a plurality of stirring rods are fixedly connected to the portion of the rotating shaft located inside the reaction box; a heating box is fixedly connected to the periphery of the reaction box; and a heating coil is installed inside the heating box.
[0014] In one alternative: a scraper is fixedly connected to the circumference of the rotating shaft, and the scraper is slidably connected to the inner wall of the reaction chamber.
[0015] In one alternative: a discharge pipe is provided at the bottom of the reaction tank, and valves are provided at both ends of the discharge pipe.
[0016] The method for determining the starch content of finished feed using the aforementioned apparatus is characterized by comprising the following steps:
[0017] S1: Feed crushing and processing: Select a certain amount of finished feed and pour it into the feed hopper 7. It is then transported to the crushing box 5 through the lifting component in the lifting box 4. The feed is then crushed to the predetermined particle size by the crushing component and then fed into the reaction box 3.
[0018] S2: Add 0.31mol / L hydrochloric acid solution into reaction tank 3 through the water inlet of reaction tank 3. The feed sample and dilute hydrochloric acid are fully mixed through the hydrolysis reaction component to form a uniform suspension.
[0019] The mass fraction of dilute hydrochloric acid is 1%-5%, and the mass-to-volume ratio of feed sample to dilute hydrochloric acid is 1:(8-15)g / mL;
[0020] The hydrolysis reaction components are mixed by stirring at a rate of 100-300 r / min for 10-20 minutes. The volume of dilute hydrochloric acid used is recorded, and the acid consumption is calculated.
[0021] S3: By heating the suspension with heating coil 13, the suspension reacts at a set temperature for a certain time, causing the starch to gelatinize and partially hydrolyze.
[0022] S4: Open the valve of the discharge pipe and pour the hydrolyzed solution into multiple glare tubes 2.
[0023] S5: Add a certain amount of potassium ferrocyanide solution and zinc acetate solution to one of the glare tubes, filter, discard the initial filtrate, and measure the optical rotation α1 of the filtrate.
[0024] S6: Add clarifying agent to another glare tube, filter, and measure the optical rotation α2 of the filtrate;
[0025] S7: Calculate the optical rotation using the following formula: W represents starch content, α1 represents total optical rotation, α2 represents the optical rotation of the ethanol-soluble substance, m1 and m2 represent sample mass, and α B 10 Specific rotation of starch.
[0026] Compared with the prior art, the beneficial effects of the present invention are as follows:
[0027] 1. This invention adopts an integrated design of the crushing component and the hydrolysis reaction component, eliminating the step of transferring the crushed feed to the hydrolysis reaction container in the traditional device, reducing operation steps and time loss, greatly improving the overall process efficiency of feed starch content determination, and shortening the detection cycle.
[0028] 2. When the rotating shaft drives the rotating block to rotate, the second slider and the arc groove work together to drive the lifting ring and the anti-blocking plate to move up and down, pressing the feed towards the crushing block to crush it, avoiding the feed from blocking the discharge port. Moreover, the pressing method is more efficient and stable than the feed falling and crushing by its own gravity.
[0029] 3. In this invention, when the magnet embedded in the rotating block rotates, the anti-blocking plate is pulled by magnetic force to slide within the lifting plate and is reset by a spring. This allows the anti-blocking plate to provide rotational force and downward pressure during the downward pressing process, further turning over the feed and spreading it evenly around the crushed block, which facilitates uniform crushing of the crushed block and improves crushing efficiency. Attached Figure Description
[0030] Figure 1 This is a schematic diagram of the structure of the present invention.
[0031] Figure 2 This is a schematic diagram of the hydrolysis reaction assembly structure of the present invention.
[0032] Figure 3 This is a partial cross-sectional view of the hydrolysis reaction assembly of the present invention.
[0033] Figure 4 For the present invention Figure 3 Enlarged view of point A in the middle.
[0034] Figure 5 This is a schematic diagram of the structure of the broken block of the present invention.
[0035] Figure 6 This is a schematic diagram of the arc-shaped groove structure of the present invention.
[0036] Figure 7 This is a schematic diagram of the anti-blocking plate structure of the present invention.
[0037] Figure label annotations: 1. Rotator, 2. Illumination tube, 3. Reaction box, 4. Lifting box, 5. Crushing box, 6. First motor, 7. Feed hopper, 8. Spiral rod, 9. Guide tube, 10. Rotating shaft, 11. Scraper, 12. Stirring rod, 13. Heating coil, 14. Heating box, 15. Feed pipe, 16. Guide rail, 17. First slider, 18. Rotating block, 19. Magnet, 20. Crushing block, 21. Stop block, 22. Second slider, 23. Lifting ring, 24. Lifting plate, 25. Anti-blocking plate, 26. Third slider, 27. Spring, 28. Arc groove, 29. Second motor. Detailed Implementation
[0038] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments.
[0039] In one embodiment, such as Figures 1-7As shown, an apparatus for determining the starch content of finished feed includes a polarimeter 1, a cyclotron tube 2, a reaction chamber 3, a lifting box 4, and a crushing box 5. The reaction chamber 3 contains a hydrolysis reaction assembly to improve the efficiency of the feed hydrolysis reaction. The crushing box 5 is located on the upper surface of the reaction chamber 3, and contains a crushing assembly to crush the feed to a predetermined particle size. A guide pipe 9 connects the lifting box 4 and the crushing box 5, and the guide pipe 9 is equipped with a valve. The lifting box 4 contains a lifting assembly to lift and transport the feed to the crushing box 5. The cyclotron tube 2 holds the products after the feed hydrolysis reaction. The polarimeter 1 measures the optical rotation of the products after the feed hydrolysis reaction, and the starch content in the finished feed is calculated based on the optical rotation and known coefficients. A water inlet is located on the upper surface of the reaction chamber 3, and a valve is installed at the water inlet for injecting dilute hydrochloric acid into the reaction chamber 3.
[0040] This invention integrates the crushing component and the hydrolysis reaction component into a single design.
[0041] In one embodiment, the lifting assembly includes a screw rod 8, a second motor 29, and a feed hopper 7. The feed hopper 7 is connected to the side wall of the lifting box 4 through a feed pipe 15. The second motor 29 is fixedly connected to the lower surface of the lifting box 4 through a bracket. The screw rod 8 is connected to the lifting box 4 through a bearing. The screw rod 8 is connected to the output end of the second motor 29.
[0042] The feed is poured into the feed hopper 7, and the second motor 29 is started. The second motor 29 drives the screw 8 to rotate. The rotating screw 8 transports the feed to the top, and then enters the reaction chamber 3 through the guide pipe 9. It is then transported to the crushing chamber 5 through the lifting component in the lifting box 4.
[0043] In one embodiment, the crushing assembly includes a first motor 6, a rotating block 18, and a rotating shaft 10. A crushing box 5 is fixedly connected to the upper surface of the reaction chamber 3. The first motor 6 is provided on the upper surface of the crushing box 5. The crushing box 5 is connected to the rotating shaft 10 through a bearing. The rotating shaft 10 is fixedly connected to the rotating block 18. The rotating block 18 has a trapezoidal cross section. Several crushing blocks 20 are provided at the bottom of the rotating block 18. The crushing box 5 has a trapezoidal cross section. A feed inlet is provided at the connection between the crushing box 5 and the reaction chamber 3.
[0044] Start the first motor 6, which drives the rotating shaft 10 to rotate. The rotating shaft 10 rotates the rotating block 18, which in turn rotates the crushing block 20. The crushing block 20 engages with the inclined surface of the crushing box 5 to crush the feed. The crushed feed enters the reaction box 3 through the feed inlet between the crushing box 5 and the reaction box 3.
[0045] In one embodiment, two symmetrical guide rails 16 are fixedly connected to the inner wall of the crushing box 5. A first slider 17 is slidably connected to the inner side wall of the guide rail 16. The two first sliders 17 are fixedly connected to a lifting ring 23 through a bracket. Two symmetrical second sliders 22 are fixedly connected to the inner wall of the lifting ring 23. An arc groove 28 is opened on the circumference of the rotating block 18. The second slider 22 is slidably connected to the inner wall of the arc groove 28. An anti-blocking plate 25 is provided below the lifting ring 23.
[0046] While the rotating shaft 10 drives the rotating block 18 to rotate, the second slider 22 cooperates with the arc groove 28 to drive the lifting ring 23 to move up and down. The up and down movement of the lifting ring 23 drives the anti-blocking plate 25 to move up and down, pressing the feed towards the crushing block 20 for crushing. On the one hand, this can avoid the feed from blocking the outlet. On the other hand, compared with crushing by the feed falling under its own gravity, the pressing method is more efficient and stable.
[0047] In one embodiment, the rotating block 18 is embedded with two magnets 19, the lower surface of the lifting ring 23 is fixedly connected to a lifting plate 24, the lifting plate 24 is provided with an anti-blocking plate groove, the anti-blocking plate 25 is slidably connected to the inner side wall of the anti-blocking plate groove, a spring is fixedly connected between the anti-blocking plate 25 and the inner side wall of the anti-blocking plate groove, and the anti-blocking plate 25 is made of ferromagnetic material.
[0048] As the arc-shaped groove 28 rotates, it drives the two internal magnets 19 to rotate. During the rotation of the magnets 19, the anti-blocking plate 25 is pulled by magnetic force to slide within the lifting plate 24 and then reset by the spring 37. This allows the anti-blocking plate 25 to provide rotational force and downward pressure during the downward pressing process. Compared with pressing directly down from top to bottom, it can further agitate the feed, allowing the feed to be evenly spread around the crushed block 20, so that the crushed block 20 can be crushed evenly, which helps to improve the crushing efficiency.
[0049] In one embodiment, a stop block 21 is fixedly connected to the upper surface of the lifting ring 23.
[0050] In one embodiment, the hydrolysis reaction assembly includes a stirring rod 12, a heating coil 13, and a heating box 14. A rotating shaft 10 extends through into the reaction box 3. A plurality of stirring rods 12 are fixedly connected to the portion of the rotating shaft 10 located inside the reaction box 3. A heating box 14 is fixedly connected to the periphery of the reaction box 3, and a heating coil 13 is provided inside the heating box 14.
[0051] The rotating shaft 10 drives the stirring rod 12 to rotate, which fully mixes the feed sample with dilute hydrochloric acid, and finally forms a uniform suspension.
[0052] Heating by heating coil 13 allows the suspension to react at a set temperature for a certain time, causing the starch to gelatinize and partially hydrolyze.
[0053] In one embodiment, a scraper 11 is fixedly connected to the circumference of the rotating shaft 10, and the scraper 11 is slidably connected to the inner wall of the reaction chamber 3.
[0054] The rotating shaft 10 can drive the scraper 11 to rotate, scraping off the suspended matter attached to the inner wall of the reaction chamber 3 and re-entering it into the suspension, thus avoiding a decrease in concentration due to sampling and causing a large measurement error.
[0055] In one embodiment, a discharge pipe is provided at the bottom of the reaction chamber 3, and valves are provided at both ends of the discharge pipe.
[0056] The above embodiments disclose an apparatus for determining the starch content of finished feed products, the specific working principle and process of which are as follows:
[0057] S1: Pour the feed into the feed hopper 7, start the second motor 29, the second motor 29 drives the screw 8 to rotate, the screw 8 rotates to transport the feed to the top, and then enters the reaction chamber 3 through the guide pipe 9, and is transported to the crushing chamber 5 through the lifting component in the lifting box 4. Start the first motor 6, the first motor 6 drives the rotating shaft 10 to rotate, the rotating shaft 10 rotates to drive the rotating block 18 to rotate, the rotating block 18 rotates to drive the crushing block 20 to rotate, the crushing block 20 cooperates with the inclined surface of the crushing chamber 5 to crush the feed, and the crushed feed enters the reaction chamber 3 from the feed inlet between the crushing chamber 5 and the reaction chamber 3;
[0058] While the rotating shaft 10 drives the rotating block 18 to rotate, the second slider 22 cooperates with the arc groove 28 to drive the lifting ring 23 to move up and down. The up and down movement of the lifting ring 23 drives the anti-blocking plate 25 to move up and down, pressing the feed towards the crushing block 20 for crushing. On the one hand, this can avoid the feed from blocking the outlet. On the other hand, compared with crushing by the feed falling under its own gravity, the pressing method is more efficient and stable.
[0059] As the arc-shaped groove 28 rotates, it drives the two magnets 19 inside to rotate. During the rotation of the magnets 19, the anti-blocking plate 25 is pulled by magnetic force to slide within the lifting plate 24. This allows the anti-blocking plate 25 to provide rotational force and downward pressure during the downward pressing process. Compared to pressing directly down from top to bottom, this further agitates the feed, allowing it to be evenly spread around the crushed block 20, enabling the crushed block 20 to be crushed uniformly, which helps to improve the crushing efficiency.
[0060] S2: Add an appropriate amount of dilute hydrochloric acid into the reaction chamber 3 through the water inlet of the reaction chamber 3. The stirring rod 12 is rotated by the rotating shaft 10 to fully mix the feed sample with the dilute hydrochloric acid, and finally form a uniform suspension. The rotating shaft 10 can also drive the scraper 11 to rotate, scraping off the suspended matter attached to the inner wall of the reaction chamber 3 and re-entering it into the suspension, avoiding the concentration reduction caused by sampling and resulting in a large measurement error.
[0061] S3: By heating the suspension with heating coil 13, the suspension reacts at a set temperature for a certain time, causing the starch to gelatinize and partially hydrolyze.
[0062] S4: Open the valve of the discharge pipe and pour the hydrolyzed solution into multiple polarimeter tubes 2 to form multiple control groups. Then transfer the solution to polarimeter 1. Add a certain amount of potassium ferrocyanide solution and zinc acetate solution to one of the polarimeter tubes, filter, discard the initial filtrate, and measure the optical rotation α1 of the filtrate. Add a clarifying agent to another polarimeter tube, filter, and measure the optical rotation α2 of the filtrate. Calculate the optical rotation according to the following formula: W represents starch content, α1 represents total optical rotation, α2 represents the optical rotation of the ethanol-soluble substance, m1 and m2 represent sample mass, and α B 10 Specific rotation of starch.
[0063] The products of starch hydrolysis with dilute hydrochloric acid (such as glucose) are chiral compounds with asymmetrical molecular structures. These compounds can cause a rotation of the polarization direction of plane-polarized light, a phenomenon known as optical rotation. The angle of rotation is called optical rotation, and its magnitude depends on the concentration of the chiral compound, the thickness of the liquid layer, the temperature, and the wavelength of the light.
[0064] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.
Claims
1. A device for determining the starch content of a feed product, characterized in that The utility model relates to a feed hydrolysis reaction device, including optical device (1), dazzle pipe (2), reaction box (3), lift material box (4), crushing box (5), be provided with hydrolysis reaction subassembly in the reaction box (3) for to improve feed hydrolysis reaction efficiency, be provided with crushing box (5) on the upper surface of reaction box (3), be provided with crushing subassembly in the crushing box (5) for crushing feed to predetermined granularity, be connected with guide pipe (9) between lift material box (4) and crushing box (5), guide pipe (9) is provided with valve, be provided with lifting subassembly in lift material box (4) for lifting transport feed to crushing box (5) in, dazzle pipe (2) is used for containing feed hydrolysis reaction product, optical device (1) is used for the determination of optical rotation of feed hydrolysis reaction product, and then the starch content in feed finished product is calculated according to optical rotation and known coefficient, the upper surface of reaction box (3) is provided with water inlet, and the water inlet is provided with valve, for injecting dilute hydrochloric acid into reaction box (3).
2. A device for determining the starch content of a feed product according to claim 1, characterized in that The lifting subassembly includes a screw rod (8), a second motor (29) and a feeding hopper (7), the sidewall of the lift material box (4) is connected with the feeding hopper (7) through a feeding pipe (15), the lower surface of the lift material box (4) is fixedly connected with the second motor (29) through a support, the lift material box (4) is connected with the screw rod (8) through a bearing, and the screw rod (8) is connected with the output end of the second motor (29).
3. A device for determining starch content of a feed product according to claim 1, characterized in that, The crushing subassembly includes a first motor (6), a rotating block (18) and a rotating shaft (10), the upper surface of the reaction box (3) is fixedly connected with the crushing box (5), the upper surface of the crushing box (5) is provided with the first motor (6), the crushing box (5) is connected with the rotating shaft (10) through a bearing, the rotating shaft (10) is fixedly connected with the rotating block (18), the cross section of the rotating block (18) is trapezoidal, the bottom of the rotating block (18) is provided with a plurality of crushing blocks (20), the cross section of the crushing box (5) is trapezoidal, and the crushing box (5) is connected with the reaction box (3) and is provided with a feeding port.
4. A device for determining the starch content of a feed product according to claim 3, characterized in that The inner wall of the crushing box (5) is fixedly connected with two symmetrical guide rails (16), the inner side wall of the track of the guide rail (16) is slidably connected with a first sliding block (17), the two first sliding blocks (17) are jointly fixedly connected with a lifting ring (23) through a support, the inner wall of the lifting ring (23) is fixedly connected with two symmetrical second sliding blocks (22), the circumferential side of the rotating block (18) is provided with an arc-shaped groove (28), the second sliding block (22) is slidably connected with the inner wall of the arc-shaped groove (28), and the lower portion of the lifting ring (23) is provided with an anti-blocking plate (25).
5. A device for determining the starch content of a feed product according to claim 4, characterized in that The rotating block (18) is embedded with two magnets (19), the lower surface of the lifting ring (23) is fixedly connected with a lifting plate (24), the lifting plate (24) is provided with an anti-blocking plate groove, the anti-blocking plate (25) is slidably connected with the inner side wall of the anti-blocking plate groove, a spring is fixedly connected between the anti-blocking plate (25) and the inner side wall of the anti-blocking plate groove, and the anti-blocking plate (25) is made of ferromagnetic material.
6. A device for determining the starch content of a feed product according to claim 4, characterized in that The upper surface of the lifting ring (23) is fixedly connected with a stop block (21).
7. A device for determining the starch content of a feed product according to claim 3, characterized in that The hydrolysis reaction assembly comprises stirring rods (12), a heating coil (13) and a heating box (14), the rotating shaft (10) extends through the reaction box (3), the rotating shaft (10) is fixedly connected with a plurality of stirring rods (12) in the reaction box (3), the reaction box (3) is fixedly connected with the heating box (14) on the side, and the heating box (14) is provided with the heating coil (13).
8. A device for determining starch content of a feed product according to claim 3, characterized in that, The rotating shaft (10) is fixedly connected with a scraper (11) on the side, and the scraper (11) is slidably connected with the inner wall of the reaction box (3).
9. The apparatus of claim 1, wherein, The reaction box (3) is provided with a discharge pipe at the bottom, and valves are arranged at both ends of the discharge pipe.
10. A method for determining the starch content of a feed product using the apparatus of any one of claims 1 to 9, characterized in that, The method comprises the following steps: S1: feed crushing treatment: a certain amount of feed product is poured into the feeding hopper (7), transported to the crushing box (5) through the lifting assembly in the lifting box (4), and then crushed to a predetermined particle size through the crushing assembly and then put into the reaction box (3); S2: 0.31 mol / L hydrochloric acid solution is added to the reaction box (3) from the water inlet of the reaction box (3), the feed sample and the dilute hydrochloric acid are fully mixed through the hydrolysis reaction assembly, and finally a uniform suspension is formed; The mass fraction of dilute hydrochloric acid is 1%-5%, and the mass-volume ratio of the feed sample to dilute hydrochloric acid is 1:(8-15) g / mL; The mixing mode of the hydrolysis reaction assembly is stirring and mixing, the stirring rate is 100-300 r / min, the stirring time is 10-20 minutes, the volume of the dilute hydrochloric acid used is recorded, and the acid consumption is calculated; S3: the suspension is reacted at a set temperature for a certain time through the heating of the heating coil (13), so that the starch is gelatinized and partially hydrolyzed; S4: open the valve of the discharge pipe, and pour the hydrolyzed solution into a plurality of light pipes (2), S5: a certain amount of potassium ferrocyanide solution and zinc acetate solution are added to one of the light pipes, the initial filtrate is discarded, and the optical rotation degree α1 of the filtrate is measured S6: add a clarifying agent to another light pipe, filter, and measure the optical rotation degree α2 of the filtrate. S7: Calculate the optical rotation according to the following formula: W is the starch content, a1 is the total optical rotation, a2 is the ethanol solubles optical rotation, m1 and m2 are the sample masses, a B 10 is the specific optical rotation of the starch.