Method for identifying mutton by using stable isotope method

Abstract

The invention discloses a method for identifying mutton by using a stable isotope method, and relates to the technical field of animal product origin traceability, and the method comprises the following steps: (1) carrying out ossein extraction on sheep bones; (2) determining stable isotope delta 13C and delta 15N values of ossein extracted from sheep bones; (3) performing significant difference multiple comparison-Duncan analysis on delta 13C and delta 15N values of ossein in sheep bones by using statistical software; (4) carrying out PLS-DA partial least square discriminant analysis on delta 13C and delta 15N values of ossein in sheep bones by using statistical software; through further optimization of ossein extraction, the extraction efficiency of ossein is improved, rapid source tracing of mutton is realized, and the problems that in the prior art, the extraction process of ossein is long in time consumption, and the rapid source tracing requirement is difficult to meet are solved.

Description

Technical Field

[0001] This invention relates to the field of livestock product origin traceability technology, and in particular to a method for identifying mutton using stable isotope analysis. Background Technology

[0002] With the continuous increase in mutton consumption, problems such as adulteration and the sale of inferior mutton have also emerged. These food safety issues not only harm consumers' health but also damage the mutton industry, especially local industries. Therefore, tracing the origin of mutton sheep can effectively combat adulteration, protect consumer health, and also help maintain the reputation and market value of local mutton brands.

[0003] For example, Chinese patent application number CN201910397641.8 describes a method for tracing the origin of mutton sheep using stable isotopes of collagen. This invention relates to the field of livestock product origin tracing technology, and in particular, a method for tracing the origin of mutton sheep using stable isotopes of collagen. The specific steps of this method are: a) extracting collagen from sheep bones; b) stabilizing the collagen extracted from sheep bones using the δ-isotope method. 13 C and δ 15 c) Determination of N value; c) Application of statistical software to analyze the δ-value of collagen in sheep bones. 13 C and δ 15 N-value was used for multiple comparisons of significant differences - Duncan analysis; d) Statistical software was used to analyze the δ-values ​​of collagen in sheep bones. 13 C and δ 15 The N value was analyzed using PLS-DA partial least squares discriminant analysis. This invention extracts collagen from sheep bones and measures the δ-value of collagen from sheep bones in different regions. 13 C and δ 15 The N value is used to trace the origin of mutton, thereby ensuring the quality and safety of mutton and protecting people's health.

[0004] While the above solutions can improve the traceability of mutton sheep to some extent, the extraction process of collagen is time-consuming and cannot meet the needs of rapid traceability. Summary of the Invention

[0005] This application provides a method for identifying mutton using stable isotope extraction, which solves the problem that the extraction process of collagen in the prior art is time-consuming and cannot meet the needs of rapid traceability. By further optimizing the extraction of collagen, the efficiency of collagen extraction is improved, and rapid traceability of mutton is achieved.

[0006] This application provides a method for identifying mutton using stable isotope analysis, specifically including the following steps: (1) Extract collagen from sheep bones; (2) Stabilizing the isotope δ of the collagen extracted from sheep bones. 13 C and δ 15 Determination of N value; (3) Statistical analysis software was used to analyze the collagen δ in sheep bones. 13 C and δ 15 The N-value was used for multiple comparisons of significant differences - Duncan analysis; (4) Statistical analysis software was used to analyze the collagen δ in sheep bones. 13 C and δ 15 PLS-DA partial least squares discriminant analysis was performed on the N value; In step (1), the method for extracting collagen specifically includes the following steps: 1) Clean the surface of the bone sample with deionized water; grind the surface of the removed sheep bones and remove the meat from the bone surface; place the bone sample in a petri dish in an oven at 60℃ for drying, take it out every 12 hours, weigh it and calculate the difference between the previous and next times. When the difference is less than 0.05g, the drying is complete. 2) Crush the bone sample into particles smaller than 2 mm and include them in the weight of each sample. Place the bone sample in a glass beaker, add deionized water, and clean it twice in an ultrasonic cleaner for 3 minutes each time. Remove the sample from the cleaning solution, add 2 mol / L HCl solution until the bone sample is completely soaked, transfer the mixture of bone sample and HCl solution to a bone sample screening device with a sieve, place the bone sample in the lower layer of the sieve, seal the device with plastic wrap, and place it in a 4°C refrigerator for decalcification. Every 4-6 hours, push the bone sample in the lower layer of the sieve to allow it to pass through the sieve and come into contact with HCl. Change the acid solution daily until the bone sample is soft and no more bubbles emerge. Remove the soft, floating bone samples and wash them with deionized water until neutral; then soak them in 0.125 mol / L NaOH solution for 24 hours to remove humic acid. 3) After processing, transfer the bone sample into a plastic centrifuge tube, add deionized water, centrifuge at 5000 rpm for 15 min, and discard the supernatant; repeat this step until the bone sample is neutral. 4) Add 0.001 mol / L HCl solution, seal with tin foil and place in a 90℃ oven for gelatinization; after gelatinization, filter the remaining liquid, take the supernatant into a new 10 ml centrifuge tube, freeze-dry to obtain collagen; grind the obtained collagen into powder using a grinder for later use.

[0007] Furthermore, step (1) the sheep bones comprise the skull and long bones.

[0008] Furthermore, the bone sample screening device is equipped with a 0.075mm sieve.

[0009] Furthermore, the bone sample screening device also includes four levels of sieves: a first sieve, a second sieve, a third sieve, and a fourth sieve, with sieve apertures of 1.5 mm, 0.5 mm, 0.15 mm, and 0.075 mm, respectively.

[0010] Furthermore, a baffle is provided below the bone sample screening device; the bone sample screening device is equipped with a pump to circulate the system.

[0011] Further, step 2) specifically involves transferring the mixture formed by the bone sample and HCl solution to a bone sample screening device. The mixture first passes through the first screen, then through the second and third screens in sequence, and finally flows into the fourth screen through a pipe. A pump is used to circulate the mixture in the device to ensure that the bone sample is in full contact with HCl. The bone samples sieved out by the sieve contain hard bone particles. After wrapping the hard bone particles in plastic wrap, they are rolled and then mixed with HCl solution and added to the bone sample sieve device. Change the acid solution daily until the bone-like structure softens and no more bubbles appear.

[0012] Furthermore, in step 2), the flow rate of the mixture is 60-120 mL / min.

[0013] Furthermore, a material-blocking section is added between the first, second, and third screens of the bone sample screening device.

[0014] Furthermore, a baffle plate is provided in the baffle section, and the baffle plate is ring-shaped.

[0015] Furthermore, the annular baffle plate of the baffle section is composed of multiple baffle plates, each of which is equipped with a magnet. A corresponding magnet is arranged on the outside of the baffle section. The interaction between the external magnet and the magnet of the baffle plate enables the baffle plate to be attracted to the inner wall of the baffle section.

[0016] One or more technical solutions provided in the embodiments of this application have at least the following technical effects or advantages: Firstly, during a sheep's growth, the stable isotopes in its bones are influenced by the geographical environment, leading to regional differences in isotope ratios. Different regions have varying natural conditions such as vegetation and water sources, causing sheep to absorb and accumulate isotope ratios with regional characteristics during grazing. Furthermore, the skull and long bones form at different times during a sheep's growth and record different growth information. The skull primarily forms during the sheep's juvenile stage, reflecting more of the environmental information of its birthplace, while long bones continue to develop as the sheep grows, recording environmental changes during growth, particularly changes in its place of origin. By combining measurements of the stable isotope ratios of collagen in the skull and long bones, a more comprehensive understanding of the sheep's growth process and migration routes can be obtained. This method, combining information from both birthplace and place of origin, improves the accuracy and reliability of tracing the origin of a sheep. By using a sieve and intermittent pushing method, sufficient contact and mixing of bone sample particles with HCl solution are ensured, improving the uniformity of decalcification and avoiding problems such as incomplete or excessive decalcification in certain areas. This significantly shortens the time required for the decalcification process and improves the efficiency of collagen extraction, which is particularly important for scenarios requiring rapid traceability. It can speed up the entire analysis process. At the same time, due to the improved uniformity of decalcification, the accuracy of traceability results is also improved. By adjusting parameters such as the pushing time interval and the acid replacement time, it can be optimized according to different bone sample characteristics and experimental requirements, improving the flexibility and adaptability of operation. This solution makes the collagen preparation process more efficient and controllable, expanding its application range. Secondly, the combination of a four-stage sieve and a circulating flow mechanism significantly improves the contact efficiency and mixing uniformity between bone sample particles and HCl solution, thereby accelerating the decalcification process and shortening the decalcification time. The sieve screening ensures the uniformity of bone sample particle size, while the circulating flow mechanism promotes thorough mixing of bone sample particles with HCl solution. The combination of these two factors makes the decalcification process more uniform, avoiding the problems of incomplete or excessive decalcification in certain areas. The more uniform decalcification process results in higher quality final collagen, providing a more accurate and reliable basis for subsequent stable isotope determination and source tracing analysis. By adjusting parameters such as sieve aperture, circulating flow speed, and roller pressing conditions, optimization can be performed according to different bone sample characteristics and experimental requirements, improving the flexibility and adaptability of the operation. Thirdly, the addition of the baffle section effectively avoids the accumulation of a large number of bone sample particles on the screen, ensuring smooth circulation of the mixture and further promoting sufficient contact between the bone sample and the HCl solution. The baffle section not only collects particles that are difficult to pass through the screen, but also facilitates subsequent roller pressing of these particles, allowing them to participate in the decalcification process again. This ensures that all bone sample particles are effectively processed, improving the screening effect and the extraction efficiency of bone collagen. The circulating flow mechanism allows the mixture to circulate continuously within the system, ensuring that each bone sample particle is in uniform and continuous contact with the acid solution. The baffle section further promotes the uniform distribution of the mixture, avoiding the problems of incomplete or excessive decalcification in certain areas. By adjusting parameters such as screen aperture, circulation speed, and roller pressing conditions, optimization can be performed according to different bone sample characteristics and experimental requirements, improving the flexibility and adaptability of bone collagen preparation. Fourth, the annular baffle plate consists of multiple baffle plates, each equipped with a magnet. Corresponding magnets are also located on the outside of the baffle section. These external magnets interact with the magnets inside the baffle plates, using magnetic force to tightly adhere the baffle plates to the inner wall of the baffle section. This magnetic adsorption mechanism not only ensures the stability of the baffle plates during operation but also facilitates subsequent cleaning and maintenance. The annular baffle plate itself acts as a physical barrier, preventing the passage of bone particles and avoiding localized accumulation on the screen. Through the combined effects of magnetic adsorption and mechanical obstruction, bone particles are evenly distributed on the screen, thereby improving screening efficiency and processing effect. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the bone sample screening device according to Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of the bone sample screening device according to Embodiment 2 of the present invention; Figure 3 This is a schematic diagram of the bone sample rolling process in Embodiment 2 of the present invention; Figure 4 This is a schematic diagram of the bone sample screening device according to Embodiment 3 of the present invention; Figure 5 This is a schematic diagram of the material blocking part structure according to Embodiment 3 of the present invention; Figure 6 This is a schematic diagram of the material blocking part structure in Embodiment 4 of the present invention. Detailed Implementation

[0018] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to limit the invention; the term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0019] Example 1: A method for identifying mutton using stable isotope analysis, the specific steps of which are as follows: (1) Extract collagen from sheep bones; Sheep bones include the skull and long bones; (2) Stabilizing the isotope δ of the collagen extracted from sheep bones. 13 C and δ 15 Determination of N value; (3) Statistical analysis software was used to analyze the collagen δ in sheep bones. 13 C and δ 15 The N-value was used for multiple comparisons of significant differences - Duncan analysis; (4) Statistical analysis software was used to analyze the collagen δ in sheep bones. 13 C and δ 15PLS-DA partial least squares discriminant analysis was performed on the N value; In step (1), the method for extracting collagen specifically includes the following steps: Clean the surface of the bone sample with deionized water; grind the surface of the removed sheep bones and remove the meat from the bone surface; place the bone sample in a petri dish in an oven at 60℃ for drying, take it out every 12 hours, weigh it and calculate the difference between the previous and next times. When the difference is less than 0.05g, the drying is complete. 2) Crush the bone sample into particles smaller than 2 mm and include them in the weight of each sample. Place the bone sample in a glass beaker, add deionized water, and clean it twice in an ultrasonic cleaner for 3 minutes each time. like Figure 1 As shown, the sample was removed from the cleaning solution, and 2 mol / L HCl solution was added until the bone sample was completely soaked. The mixture of bone sample and HCl solution was transferred to a bone sample screening device containing a 0.075 mm sieve. The bone sample was placed in the lower layer of the sieve. The device was sealed with plastic wrap and placed in a 4°C refrigerator for decalcification. Every 4-6 hours, the bone sample in the lower layer of the sieve was pushed to pass through the sieve and come into contact with HCl. The acid solution was changed daily until the bone sample was soft and no more bubbles emerged. Remove the soft, floating bone samples and wash them with deionized water until neutral; then soak them in 0.125 mol / L NaOH solution for 24 hours to remove humic acid. 3) After processing, transfer the bone sample into a plastic centrifuge tube, add deionized water, centrifuge at 5000 rpm for 15 min, and discard the supernatant; repeat this step until the bone sample is neutral. 4) Add 0.001 mol / L HCl solution, seal with tin foil and place in a 90℃ oven for gelatinization; after gelatinization, filter the remaining liquid, take the supernatant into a new 10 ml centrifuge tube, freeze-dry to obtain collagen; grind the obtained collagen into powder using a grinder for later use.

[0020] Experimental measurements were conducted for this embodiment. The comparative example used the Chinese patent method with application number CN201910397641.8 for tracing the origin of mutton. The difference between this embodiment and the comparative example is that the tested sheep bones include the skull and long bones, and a bone sample screening device is used in the process of extracting bone collagen.

[0021] The technical solutions described in the embodiments of this application have at least the following technical effects or advantages: During a sheep's growth, the stable isotopes in its bones are affected by the geographical environment, leading to regional differences in isotope ratios. Different regions have different natural conditions such as vegetation and water sources, so sheep absorb and accumulate isotope ratios with regional characteristics during grazing. The skull and long bones form at different times during a sheep's growth and record different growth information. The skull is mainly formed during the sheep's juvenile period and reflects more of the environmental information of its birthplace, while the long bones continue to develop as the sheep grows and can record environmental changes during the growth process, especially changes in the birthplace. By combining measurements of the stable isotope ratio of collagen in the skull and long bones, a more comprehensive understanding of the growth process and migration route of sheep can be obtained; this method combines information on birthplace and place of origin, improving the accuracy and reliability of tracing the origin of sheep. By introducing a bone sample screening device and intermittently pushing the bottom layer of bone samples, the bone samples are passed through the sieve to screen out finer bone samples, thereby allowing the bone samples to fully contact HCl and accelerate the decalcification process. At the same time, during this process, some bone samples will be broken down and reduced in size under the action of the sieve, further promoting decalcification and improving the overall efficiency of bone collagen preparation. The bone sample is sieved into finer particles using a sieve in the bone sample screening device. These finer particles have a significantly increased contact area with the HCl solution, allowing the acid to penetrate the bone sample more quickly and evenly, accelerating the decalcification process. Intermittent squeezing or pushing of the bottom layer of bone sample not only promotes thorough mixing of the bone particles with the HCl solution but also causes some bone samples to break down and shrink under the action of the sieve, promoting the diffusion and exchange of calcium ions and other substances generated during decalcification, further accelerating the decalcification rate. The sieve screening ensures the uniformity of bone sample particle size, making the decalcification process more uniform and avoiding the problems of incomplete or excessive decalcification in certain areas. The more uniform decalcification process improves the quality of the final bone collagen, providing a more accurate and reliable basis for subsequent stable isotope determination and source tracing analysis. By using a sieve and intermittent pushing method, sufficient contact and mixing of bone sample particles with HCl solution are ensured, improving the uniformity of decalcification and avoiding problems such as incomplete or excessive decalcification in certain areas. This significantly shortens the time required for the decalcification process and improves the efficiency of collagen extraction, which is particularly important for scenarios requiring rapid traceability. It can accelerate the entire analysis process. At the same time, due to the improved uniformity of decalcification, the accuracy of traceability results is also improved. By adjusting parameters such as the pushing time interval and the acid replacement time, optimization can be performed according to different bone sample characteristics and experimental requirements, improving the flexibility and adaptability of the operation. This method makes the collagen preparation process more efficient and controllable, expanding its application range.

[0022] Example 2: The above Example 1, through sieve screening and intermittent pushing, allows the bone sample to come into more complete contact with the HCl solution, significantly shortening the time required for the decalcification process. To further improve the efficiency of the bone collagen preparation process, further improvements were made based on Example 1.

[0023] like Figure 2 As shown, the bone sample screening device includes four sieves: a first sieve, a second sieve, a third sieve, and a fourth sieve, with sieve apertures of 1.5 mm, 0.5 mm, 0.15 mm, and 0.075 mm, respectively. A baffle is installed at the bottom of the device to guide the flow direction of the mixture. The bone sample screening device is equipped with a pump to circulate the mixture within the system. Specifically, in step 2), the mixture formed by the bone sample and HCl solution is transferred to the bone sample screening device, which includes four screens: a first screen of 1.5 mm, a second screen of 0.5 mm, a third screen of 0.15 mm, and a fourth screen of 0.075 mm. The mixture first passes through the first screen, then through the second and third screens in sequence, and finally flows into the fourth screen through a pipe. A pump is used to circulate the mixture in the device to ensure that the bone sample is in full contact with HCl. The flow rate of the mixture is 60-120 mL / min; like Figure 3 As shown, the bone samples sieved out by the sieve contain hard bone particles. The hard bone particles are wrapped in plastic wrap and then rolled. The rolled bone samples are then mixed with HCl solution and added to the bone sample sieving device. Change the acid solution daily until the bone-like structure softens and no more bubbles appear.

[0024] Experimental measurements were conducted for this embodiment. The difference between this embodiment and Embodiment 1 is that in this embodiment, the mixture of bone sample and HCl solution is transferred to a bone sample screening device. This bone sample screening device includes four sieves: a first sieve of 1.5 mm, a second sieve of 0.5 mm, a third sieve of 0.15 mm, and a fourth sieve of 0.075 mm. The mixture first passes through the first sieve, then sequentially through the second and third sieves, and finally flows into the fourth sieve through a pipe. A pump is used to circulate the mixture in the device, ensuring that the bone sample and HCl are in full contact. The flow rate of the mixture is 60-120 mL / min; The bone samples sieved out by the sieve contain hard bone particles. After wrapping the hard bone particles in plastic wrap, they are rolled and then mixed with HCl solution and added to the bone sample sieve device. Change the acid solution daily until the bone-like structure softens and no more bubbles appear.

[0025] The technical solutions described in the embodiments of this application have at least the following technical effects or advantages: By setting up four-stage sieves with different apertures, bone sample particles can be screened step by step. As the bone sample particles pass through each stage of the sieve, they can be refined step by step, causing the bone sample to be gradually broken into smaller particles. This greatly increases the contact area with the HCl solution, which is conducive to the acid solution penetrating into the bone sample more quickly and evenly, accelerating the decalcification process, and allowing the bone sample particles to come into more full contact with the acid solution, thus accelerating the decalcification process. The baffles and pumps at the bottom of the device allow the mixture to circulate within the system. This circulation further promotes the thorough mixing of the bone sample with the HCl solution, ensuring that each bone sample particle is in uniform and continuous contact with the acid solution. This avoids the problem of incomplete or excessive decalcification in certain areas. At the same time, the bone sample particles are continuously squeezed and rubbed by the screen during the flow, further breaking them down and improving the decalcification efficiency. For the hard bone samples sieved out by the screen, the hard particles are further crushed by roller pressing, so that they can react fully with HCl solution again, so that all bone samples can be effectively processed and the extraction efficiency of bone collagen is improved. By combining a four-stage sieve and a circulating flow mechanism, the contact efficiency and mixing uniformity of bone sample particles with HCl solution are significantly improved, thereby accelerating the decalcification process and shortening the decalcification time. The sieve screening ensures the uniformity of bone sample particle size, while the circulating flow mechanism promotes thorough mixing of bone sample particles with HCl solution. The combination of these two factors makes the decalcification process more uniform, avoiding the problems of incomplete or excessive decalcification in certain areas. The more uniform decalcification process results in higher quality final collagen, providing a more accurate and reliable basis for subsequent stable isotope determination and source tracing analysis. By adjusting parameters such as sieve aperture, circulating flow speed, and roller pressing conditions, optimization can be performed according to different bone sample characteristics and experimental requirements, improving the flexibility and adaptability of the operation.

[0026] Example 3: The combination of a four-stage sieve and a circulating flow mechanism in Example 2 allows for more thorough contact between the bone sample and the HCl solution, improving decalcification efficiency. To further improve the efficiency of the bone collagen preparation process, further improvements were made based on Example 2.

[0027] like Figure 4 and Figure 5 As shown, the bone sample screening device adds a baffle section between the first screen, the second screen and the third screen, and a baffle plate is installed in the baffle section. The baffle plate is annular.

[0028] Specifically, in step 2), the mixture formed by the bone sample and HCl solution is transferred to the bone sample screening device, which includes four screens: a first screen of 1.5 mm, a second screen of 0.5 mm, a third screen of 0.15 mm, and a fourth screen of 0.075 mm. The mixture first passes through the first screen, then through the second and third screens in sequence, and a baffle is added between the first, second, and third screens. Finally, it flows into the fourth screen through a pipe. A pump is used to circulate the mixture in the device to ensure that the bone sample is in full contact with HCl. The flow rate of the mixture is 60-120 mL / min; The bone samples screened out by the baffle and the screen contain hard bone particles. The hard bone particles are wrapped in plastic wrap and then rolled. The rolled bone samples are then mixed with HCl solution and added to the bone sample screening device. Change the acid solution daily until the bone-like structure softens and no more bubbles appear.

[0029] Experimental measurements were conducted for this embodiment. The difference between the experiment in this embodiment and that in embodiment two is that a baffle is added between the first screen, the second screen and the third screen in this embodiment. A baffle plate is installed in the baffle, and the baffle plate is annular.

[0030] The technical solutions described in the embodiments of this application have at least the following technical effects or advantages: Based on the existing four-stage sieve system, a baffle is added between the first, second, and third sieves. This baffle effectively blocks and guides the bone samples, preventing excessive bone particles from accumulating on the sieves, thus preventing obstruction of the mixture's circulation and ensuring uniform distribution of bone particles throughout the screening process. This avoids localized accumulation and further improves processing efficiency. An annular baffle is installed in the channel; its annular design completely seals off a portion of the channel, effectively blocking material and preventing backflow or deviation from the predetermined path. Simultaneously, particles that are difficult to pass through the sieves and are collected by the annular baffle can be further crushed by subsequent roller pressing and then reintroduced into the bone sample screening device to participate in the subsequent decalcification process, thereby improving the extraction efficiency of bone collagen. Combined with the circulating flow mechanism, the mixture circulates continuously between the various levels of screens, ensuring that bone particles can pass through the screens multiple times and fully contact the HCl solution, thereby further enhancing the decalcification efficiency and screening effect. The addition of the baffle section not only optimizes the distribution of bone particles on the screens, but also facilitates the processing of particles that are difficult to pass through the screens, further improving the efficiency of the entire process. The addition of a baffle effectively prevents the accumulation of bone sample particles on the screen, ensuring smooth circulation of the mixture and further promoting sufficient contact between the bone sample and the HCl solution. The baffle not only collects particles that are difficult to pass through the screen but also facilitates subsequent roller pressing of these particles, allowing them to participate in the decalcification process again. This ensures that all bone sample particles are effectively processed, improving screening efficiency and collagen extraction efficiency. The circulating flow mechanism allows the mixture to circulate continuously within the system, ensuring that each bone sample particle is uniformly and continuously in contact with the acid solution. The baffle further promotes uniform distribution of the mixture, avoiding problems such as incomplete or excessive decalcification in certain areas. By adjusting parameters such as screen aperture, circulation speed, and roller pressing conditions, optimization can be performed according to different bone sample characteristics and experimental requirements, improving the flexibility and adaptability of collagen preparation.

[0031] Example 4: The above Example 3 effectively avoids the accumulation of a large number of bone sample particles on the screen by setting up a baffle, thus avoiding local accumulation and further improving the processing efficiency. To further improve the efficiency of the bone collagen preparation process, further improvements are made based on Example 3.

[0032] like Figure 6 As shown, the annular baffle plate of the baffle part is composed of multiple baffle pieces, each of which is equipped with a magnet. A corresponding magnet is arranged on the outside of the baffle part. The interaction between the external magnet and the magnet of the baffle plate enables the baffle plate to be attracted to the inner wall of the baffle part.

[0033] Experimental measurements were conducted for this embodiment. The difference between the experiments in this embodiment and those in Embodiment 3 is that the annular baffle plate of the baffle part in this embodiment is composed of multiple baffle plates, each of which is equipped with a magnet. A corresponding magnet is configured on the outside of the baffle part. The interaction between the external magnet and the magnet of the baffle plate enables the baffle plate to be attracted to the inner wall of the baffle part.

[0034] The technical solutions described in the embodiments of this application have at least the following technical effects or advantages: The annular baffle plate consists of multiple baffle plates, each equipped with a magnet. Corresponding magnets are also located on the outside of the baffle section. These external magnets interact with the magnets inside the baffle plates, magnetically adsorbing the baffle plates tightly onto the inner wall of the baffle section. This magnetic adsorption mechanism not only ensures the stability of the baffle plates during operation but also facilitates subsequent cleaning and maintenance. The annular baffle plate itself acts as a physical barrier, preventing bone particles from passing through and avoiding localized accumulation on the screen. Through the combined effects of magnetic adsorption and mechanical obstruction, bone particles are evenly distributed on the screen, thereby improving screening efficiency and processing effect. The baffle plate design not only effectively blocks the passage of bone particles and prevents them from accumulating locally on the screen, but also maintains a stable state under the action of magnetic force. During operation, bone particles flow towards the screen with the fluid, while the baffle plate attracts external magnets through its built-in magnets, forming an effective barrier and improving processing efficiency. When a certain amount of bone-like particles accumulate on the baffle plate and need to be cleaned, this can be achieved by activating the transverse water flow. The transverse water flow washes the baffle plate at a certain angle, dispersing and carrying away the accumulated bone-like particles. This cleaning process can be repeated until the bone-like particles on the baffle plate are completely cleaned. The presence of the magnet ensures that the baffle plate remains in the predetermined position during the cleaning process and will not shift due to the cleaning operation, thereby ensuring the continuity and stability of the preparation process.

[0035] Performance testing: The extraction times of collagen in the comparative examples and Examples 1 to 4 were determined by testing, as shown in the table below:

[0036] The accuracy of the traceability of mutton origin in the comparative example and Examples 1 to 4 is shown in the table below:

[0037] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. For those skilled in the art, the present invention can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for identifying mutton using stable isotope analysis, characterized in that, Specifically, the steps include the following: (1) Extract collagen from sheep bones; (2) Stabilize the isotope δ of the collagen extracted from sheep bones. 13 C and δ 15 Determination of N value; (3) Statistical analysis software was used to analyze the collagen δ in sheep bones. 13 C and δ 15 The N-value was used for multiple comparisons of significant differences - Duncan analysis; (4) Statistical analysis software was used to analyze the collagen δ in sheep bones. 13 C and δ 15 PLS-DA partial least squares discriminant analysis was performed on the N value; In step (1), the method for extracting collagen specifically includes the following steps: 1) Clean the surface of the bone sample with deionized water; grind the surface of the removed sheep bones and remove the meat from the bone surface; place the bone sample in a petri dish in an oven at 60℃ for drying, take it out every 12 hours, weigh it and calculate the difference between the previous and next times. When the difference is less than 0.05g, the drying is complete. 2) Crush the bone sample into particles smaller than 2 mm and include them in the weight of each sample. Place the bone sample in a glass beaker, add deionized water, and clean it twice in an ultrasonic cleaner for 3 minutes each time. Remove the sample from the cleaning solution, add 2 mol / L HCl solution until the bone sample is completely soaked, transfer the mixture of bone sample and HCl solution to a bone sample screening device with a sieve, place the bone sample in the lower layer of the sieve, seal the device with plastic wrap, and place it in a 4°C refrigerator for decalcification. Every 4-6 hours, push the bone sample in the lower layer of the sieve to allow it to pass through the sieve and come into contact with HCl. Change the acid solution daily until the bone sample is soft and no more bubbles emerge. Remove the soft, floating bone samples and wash them with deionized water until neutral; then soak them in 0.125 mol / L NaOH solution for 24 hours to remove humic acid. 3) After processing, transfer the bone sample into a plastic centrifuge tube, add deionized water, centrifuge at 5000 rpm for 15 min, and discard the supernatant; repeat this step until the bone sample is neutral. 4) Add 0.001 mol / L HCl solution, seal with tin foil and place in a 90℃ oven for gelatinization; after gelatinization, filter the remaining liquid, take the supernatant into a new 10 ml centrifuge tube, freeze-dry to obtain collagen; grind the obtained collagen into powder using a grinder for later use.

2. The method for identifying mutton using stable isotope method as described in claim 1, characterized in that, Step (1) The sheep bones consist of the skull and long bones.

3. The method for identifying mutton using stable isotope method as described in claim 1, characterized in that, The bone sample screening device is equipped with a 0.075mm sieve.

4. The method for identifying mutton using stable isotope method as described in claim 3, characterized in that, The bone sample screening device also includes four levels of sieves: a first sieve, a second sieve, a third sieve, and a fourth sieve, with sieve apertures of 1.5 mm, 0.5 mm, 0.15 mm, and 0.075 mm, respectively.

5. The method for identifying mutton using stable isotope method as described in claim 4, characterized in that, The bone sample screening device is equipped with a baffle at the bottom; the bone sample screening device is equipped with a pump to circulate the system.

6. The method for identifying mutton using stable isotope method as described in claim 4, characterized in that, Step 2) Specifically, the mixture formed by the bone sample and HCl solution is transferred to the bone sample screening device. The mixture first passes through the first screen, then through the second and third screens in sequence, and finally flows into the fourth screen through the pipe. A pump is used to circulate the mixture in the device so that the bone sample and HCl are in full contact. The bone samples sieved out by the sieve contain hard bone particles. After wrapping the hard bone particles in plastic wrap, they are rolled and then mixed with HCl solution and added to the bone sample sieve device. Change the acid solution daily until the bone-like structure softens and no more bubbles appear.

7. The method for identifying mutton using stable isotope method as described in claim 6, characterized in that, Step 2) The flow rate of the mixture is 60-120 mL / min.

8. The method for identifying mutton using stable isotope method as described in claim 4, characterized in that, The bone sample screening device adds a material blocking section between the first screen, the second screen and the third screen.

9. The method for identifying mutton using stable isotope method as described in claim 8, characterized in that, A baffle plate is installed in the baffle section, and the baffle plate is ring-shaped.

10. The method for identifying mutton using stable isotope method as described in claim 9, characterized in that, The annular baffle plate of the baffle section is composed of multiple baffle plates, each of which is equipped with a magnet. A corresponding magnet is also arranged on the outside of the baffle section. The interaction between the external magnet and the magnet of the baffle plate enables the baffle plate to be attracted to the inner wall of the baffle section.

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