Sterilization method for reducing irradiation sterilization dosage of experimental animal feed
Through multi-step thermal activation and radiation treatment methods, the problem of high-dose irradiation sterilization of experimental animal feed is solved, and the goal of reducing irradiation dose and improving sterilization effect is achieved.
Patent Information
- Application Number
- CN202411996882.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-31
- Publication Date
- 2025-02-14
Smart Images
Figure SMS_1
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of radiation sterilization, in particular to a sterilization method for reducing the radiation sterilization dosage of experimental animal feed. Background Art
[0002] In the process of production, storage, transportation and use, animal feed is rich in protein, amino acids, fat and other nutrients, which are easily used by microorganisms to multiply in large numbers, causing feed corruption and deterioration. Pathogenic bacteria can directly cause diseases or even death in fed animals, and even pathogens can be transferred to the human body through livestock and poultry meat products, seriously endangering human health. In animal experiments, in order to ensure the accuracy of experimental data and eliminate data interference factors, the living environment conditions of experimental animals such as drinking water and food must strictly meet the sterility requirements, and experimental animal feed needs to be thoroughly sterilized to ensure interference from non-experimental microorganisms.
[0003] At present, the sterilization methods of experimental animal feed mainly include high temperature sterilization, microwave sterilization and irradiation sterilization, among which irradiation sterilization is the most widely used method with the best sterilization effect. Irradiation sterilization technology is a green processing high-tech technology, belonging to the peaceful use of atomic energy - the application category of civilian non-power nuclear technology. Compared with traditional agricultural product preservation methods such as heating, refrigeration, fumigation, chemical preservative treatment, etc., it has significant advantages such as thorough sterilization, no temperature rise, no residue, no damage to the original packaging, energy saving, and storage at room temperature.
[0004] The inventor believes that the following problems exist in sterilizing and preserving experimental animal feed using irradiation sterilization method: 1. The raw materials of feed products are mostly primary agricultural products such as grains, livestock and poultry meat, fish, etc. The raw materials are complex and come from a wide range of sources. They are prone to carry radiation-resistant spore-forming microorganisms and require high-dose irradiation to achieve a sterile effect; 2. High-dose irradiation will destroy the nutrients in feed and reduce feed quality; 3. High-dose irradiation will increase the cost of feed production companies and reduce their competitive advantage. Summary of the invention
[0005] The purpose of the present invention is to provide a sterilization method for reducing the radiation sterilization dose of experimental animal feed, thereby reducing the radiation sterilization dose of experimental animal feed, thereby reducing the impact of the radiation dose on the quality of feed products, and further reducing the cost of feed production enterprises, so as to achieve the purpose of complete sterilization of feed products.
[0006] The present invention provides a sterilization method for reducing the radiation sterilization dose of experimental animal feed, which adopts the following technical scheme: A sterilization method for reducing the radiation sterilization dose of experimental animal feed comprises the following steps: S1. Perform a heat activation treatment on the intactly packaged experimental animal feed products; S2, subjecting the experimental animal feed product processed in step S1 to high-energy electron beam irradiation treatment; S3, performing a secondary heat activation treatment on the experimental animal feed product processed in step S2; S4, subjecting the experimental animal feed product processed in step S3 to a gamma ray irradiation treatment; S5, performing low temperature treatment on the experimental animal feed product processed in step S4; S6, performing three heat activation treatments on the experimental animal feed product processed in step S5; S7. Perform secondary gamma ray irradiation treatment on the experimental animal feed product processed in step S6.
[0007] Preferably, the thermal activation treatment in step S1 is performed by water bath heating, and the well-packaged experimental animal feed product is immersed in a water bath at 90-95° C. for 50-60 minutes.
[0008] Preferably, the parameters of the high energy electron beam irradiation treatment in step S2 include a dose rate of 8-10 kGy / min and an irradiation treatment time of 30-40 s.
[0009] Preferably, the secondary heat activation treatment in step S3 is carried out by water bath heating, and the experimental animal feed product treated in step S2 is immersed in a water bath at 84-86° C. for 50-60 minutes.
[0010] Preferably, the parameters of the gamma ray irradiation treatment in step S4 include a dose rate of 0.5-0.8 kGy / min and an irradiation treatment time of 7-10 min.
[0011] Preferably, the low temperature treatment in step S5 is carried out by burying the experimental animal feed product treated in step S4 in dry ice, and taking it out for later use when the temperature of the experimental animal feed product drops to -10°C.
[0012] Preferably, the three heat activation treatments in step S6 are performed by water bath heating, and the experimental animal feed product treated in step S5 is immersed in a water bath at 80-82° C. for 50-60 minutes.
[0013] Preferably, the parameters of the secondary gamma ray irradiation treatment in step S7 include a dose rate of 1-1.5 kGy / min and an irradiation treatment time of 4-5 min.
[0014] In summary, the present invention includes the following beneficial technical effects: 1. In the present application, the experimental animal feed product is first subjected to a heat activation treatment to activate most of the spores carried in the experimental animal feed product, reduce its radiation resistance, and reduce the total radiation sterilization dose. The surface part of the experimental animal feed product is effectively irradiated in a short time by high-energy electron beam irradiation with an irradiation treatment time of 30-40s and a dose rate of 8-10kGy / min, and the influence of radiation energy on the quality of the experimental animal feed product is reduced from the perspective of shortening the irradiation time; the secondary heat activation treatment can effectively activate the spore microorganisms that have not been completely killed in the surface part of the experimental animal feed product, and then the irradiation treatment time is 7-10min and the dose rate is 0 The primary gamma ray irradiation of .5-0.8kGy / min takes advantage of the strong penetrating ability of gamma rays to effectively sterilize the deep parts of the experimental animal feed products, and at the same time performs a secondary sterilization on the small amount of microorganisms remaining on the surface; the experimental animal feed products are cooled to stimulate the remaining microorganisms to accelerate the formation of spores, and the feed products that have been subjected to low temperature stress are subjected to three heat activation treatments, and a secondary gamma ray irradiation with a dose rate of 1-1.5kGy / min and an irradiation treatment time of 4-5min is used. While shortening the total irradiation sterilization time, it ensures that higher radiation energy penetrates every part of the feed product and can effectively kill the remaining microorganisms with significantly reduced radiation tolerance.
[0015] 2. This application organically combines the characteristics of two different types of rays, namely, high-energy electron beams have high ray energy per unit time but weak penetrating power, and gamma rays have low ray energy per unit time but strong penetrating power, thereby improving the quality and efficiency of irradiation sterilization technology for experimental animal feed products.
[0016] 3. This application replaces the traditional process of irradiating feed products with only a single ray, a fixed dose rate, and normal temperature environment, and adopts two different rays, different dose rates, and different temperatures for cross-treatment, which significantly reduces the total dose of irradiation sterilization of feed products, reduces the impact of ray energy on product quality, reduces the cost of production enterprises, improves the market competitiveness of enterprises, and brings extremely high market economic benefits. DETAILED DESCRIPTION
[0017] The present invention is further described in detail below with reference to the embodiments.
[0018] A sterilization method for reducing the radiation sterilization dose of experimental animal feed comprises the following steps: S1. Perform a heat activation treatment on the well-packaged experimental animal feed products by soaking the well-packaged experimental animal feed products in a water bath at 90-95°C for 50-60 minutes; S2, subjecting the experimental animal feed product processed in step S1 to high-energy electron beam irradiation treatment, wherein the parameters of the high-energy electron beam irradiation treatment include a dose rate of 8-10 kGy / min and an irradiation treatment time of 30-40 s; S3, performing a secondary heat activation treatment on the experimental animal feed product processed in step S2, using a water bath heating method, and soaking the experimental animal feed product in a water bath at 84-86° C. for 50-60 minutes; S4, performing a gamma ray irradiation treatment on the experimental animal feed product processed in step S3, wherein the parameters of the gamma ray irradiation treatment include a dose rate of 0.5-0.8 kGy / min and an irradiation treatment time of 7-10 min; S5, performing low temperature treatment on the experimental animal feed product processed in step S4, burying the experimental animal feed product in dry ice, and taking out the experimental animal feed product when the temperature drops to -10°C for standby use; S6, performing three heat activation treatments on the experimental animal feed product processed in step S5, using a water bath heating method, soaking the experimental animal feed product in a water bath at 80-82° C. for 50-60 minutes; S7. Perform secondary gamma ray irradiation treatment on the experimental animal feed product processed in step S6. The parameters of the secondary gamma ray irradiation treatment include a dose rate of 1-1.5 kGy / min and an irradiation treatment time of 4-5 min.
[0019] Example Example 1
[0020] A sterilization method for reducing the radiation sterilization dose of experimental animal feed comprises the following steps: S1. Perform a heat activation treatment on the well-packaged experimental animal feed products by soaking them in a 90°C water bath for 58 minutes, then take them out and clean them for later use; S2, placing the experimental animal feed product processed in step S1 horizontally in a tray of a high-energy electron beam transmission device for high-energy electron beam irradiation treatment, setting the parameters of the high-energy electron beam irradiation treatment, the dose rate is 10 kGy / min, and the irradiation treatment time is 30 s; S3, performing a secondary heat activation treatment on the experimental animal feed product treated in step S2, using a water bath heating method, soaking the experimental animal feed product in a water bath pot at 85° C. for 60 minutes, taking it out and wiping it clean for later use; S4, performing a gamma ray irradiation treatment on the experimental animal feed product processed in step S3, setting parameters for the gamma ray irradiation treatment, a dose rate of 0.5 kGy / min, and an irradiation treatment time of 10 min; S5, performing low temperature treatment on the experimental animal feed product processed in step S4, burying the experimental animal feed product in dry ice, and taking out the experimental animal feed product when the temperature drops to -10°C for standby use; S6, performing three heat activation treatments on the experimental animal feed product processed in step S5, using a water bath heating method, soaking the experimental animal feed product in a water bath pot at 80° C. for 55 minutes, taking it out and wiping it clean for later use; S7. Perform secondary gamma ray irradiation treatment on the experimental animal feed product processed in step S6, and set the parameters of the secondary gamma ray irradiation treatment, the dose rate is 1 kGy / min, and the irradiation treatment time is 5 minutes.
[0021] Comparative Example Comparative Example 1 A sterilization method for experimental animal feed products is to subject them to a single gamma irradiation treatment at a dose of 25 kGy.
[0022] Comparative Example 2 A sterilization method for experimental animal feed products is to subject them to a single gamma irradiation treatment at a dose of 30 kGy.
[0023] Comparative Example 3 A sterilization method for experimental animal feed products is to subject them to a single high-energy electron beam irradiation treatment with an irradiation dose of 25 kGy.
[0024] Comparative Example 4 A sterilization method for experimental animal feed products is to subject them to a single high-energy electron beam irradiation treatment with an irradiation dose of 30 kGy.
[0025] Comparative Example 5 A sterilization method for experimental animal feed products is to subject them to a single high-energy electron beam irradiation treatment with an irradiation dose of 35 kGy.
[0026] Comparative Example 6 A sterilization method, which is different from Example 1 in that the experimental animal feed product is not subjected to the first heat activation treatment, the second heat activation treatment, the low temperature treatment and the third heat activation treatment, and the remaining steps are the same as those in Example 1.
[0027] Comparative Example 7 A sterilization method, which is different from comparative example 5 in that the dose of high-energy electron beam irradiation treatment is 7 kGy, the dose of primary gamma ray irradiation treatment is 7 kGy, the dose of secondary gamma ray irradiation treatment is 7 kGy, and the remaining steps are the same as those of the comparative example.
[0028] Comparative Example 8 A sterilization method comprising the following steps: S1. Perform a heat activation treatment on the well-packaged experimental animal feed products by soaking them in a 90°C water bath for 58 minutes, then take them out and clean them for later use; S2. The experimental animal feed product processed in step S1 is horizontally placed in a tray of a high-energy electron beam transmission device for high-energy electron beam irradiation treatment. The dose of the high-energy electron beam irradiation treatment is 20 kGy.
[0029] Comparative Example 9 A sterilization method, which is different from Comparative Example 8 in that the dosage of high-energy electron beam irradiation treatment is 25 kGy, and the remaining steps are the same as Comparative Example 8.
[0030] Comparative Example 10 A sterilization method, which is different from Comparative Example 8 in that the dosage of high-energy electron beam irradiation treatment is 30 kGy, and the remaining steps are the same as Comparative Example 8.
[0031] Comparative Example 11 A sterilization method comprising the following preparation steps: S1. Perform a heat activation treatment on the well-packaged experimental animal feed products by soaking them in a 90°C water bath for 58 minutes, then take them out and clean them for later use; S2. The experimental animal feed product processed in step S1 is subjected to gamma ray irradiation treatment, and the dose of the gamma ray irradiation treatment is 20 kGy.
[0032] Comparative Example 12 A sterilization method, which is different from Comparative Example 11 in that the dose of gamma ray irradiation treatment is 25 kGy, and the remaining steps are the same as Comparative Example 11.
[0033] Performance testing Detection Methods The experimental animal feed products were sterilized according to the sterilization methods of Example 1 and Comparative Examples 1-12, and the surfaces of the experimental animal feed product packages were wiped with 75% alcohol cotton balls for thorough disinfection. Sterile air was introduced into the experimental animal feed product packages with needles with sterilizing filters, and the experimental animal feed product packages were opened to take out feed product samples, and sterility inspection was performed using the direct inoculation method. The experimental animal feed product samples sterilized by Example 1 and Comparative Examples 1-12 were inoculated into thioglycollate fluid culture medium, and the culture medium after inoculation of the product samples was divided into two equal parts, one of which was cultured in an environment of 30-35°C, and the other was cultured in an environment of 20-25°C. After 14 days of culture, the culture medium was observed to see if it was turbid. If it was turbid, it meant that there were bacteria, i.e., positive; if it was not turbid, it meant that it was sterile, i.e., negative.
[0034]
[0035] It can be seen from the test results of Table 1 that the total irradiation dose used in the sterilization method of the present application is 15kGy, which can achieve the sterilization effect. It can be known from the test results of Comparative Examples 1 and 2 that, without heat activation treatment and low temperature treatment, gamma ray irradiation sterilization is used alone, and a 30kGy irradiation dose can achieve a sterile effect; it can be known from the test results of Comparative Examples 3-5 that, without heat activation treatment and low temperature treatment, high energy electron beam irradiation sterilization is used alone, and a 35kGy irradiation dose can achieve a sterile effect; according to the test results of Example 1 and Comparative Examples 6-7, it can be known that, without heat activation treatment and low temperature treatment, when the total irradiation dose is 21kGy, the sample sterility test is negative, and the total irradiation dose used in Example 1 is 15kGy, which shows that the heat activation treatment and low temperature treatment in the present application can play an effective role in sterilization.
[0036] From the test results of Example 1 and Comparative Examples 8-10, it can be seen that if a single high-energy electron beam irradiation treatment is used, the total dose needs to reach 30 kGy, and the sample sterility test is negative; from the test results of Example 1 and Comparative Examples 11-12, it can be seen that if a single gamma ray irradiation treatment is used, the total dose needs to reach 25 kGy, and the sample sterility test is negative. The total irradiation doses in Comparative Examples 8-12 are all higher than the total irradiation dose in Example 1 of the present application.
[0037] The above are all preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the protection scope of the present invention.
Claims
1. A sterilization method for reducing the radiation sterilization dose of experimental animal feed, characterized in that: The following steps are involved: S1. Perform a heat activation treatment on the intactly packaged experimental animal feed products; S2, subjecting the experimental animal feed product processed in step S1 to high-energy electron beam irradiation treatment; S3, performing a secondary heat activation treatment on the experimental animal feed product processed in step S2; S4, subjecting the experimental animal feed product processed in step S3 to a gamma ray irradiation treatment; S5, performing low temperature treatment on the experimental animal feed product processed in step S4; S6, performing three heat activation treatments on the experimental animal feed product processed in step S5; S7. Perform secondary gamma ray irradiation treatment on the experimental animal feed product processed in step S6.
2. A sterilization method for reducing the radiation sterilization dose of experimental animal feed according to claim 1, characterized in that: The first heat activation treatment in step S1 is carried out by water bath heating, and the well-packaged experimental animal feed product is immersed in a water bath at 90-95° C. for 50-60 minutes.
3. A sterilization method for reducing the radiation sterilization dose of experimental animal feed according to claim 1, characterized in that: The parameters of the high energy electron beam irradiation treatment in step S2 include a dose rate of 8-10 kGy / min and an irradiation treatment time of 30-40 s.
4. A sterilization method for reducing the radiation sterilization dose of experimental animal feed according to claim 1, characterized in that: The secondary heat activation treatment in step S3 is carried out by water bath heating, and the experimental animal feed product treated in step S2 is immersed in a water bath at 84-86° C. for 50-60 minutes.
5. A sterilization method for reducing the radiation sterilization dose of experimental animal feed according to claim 1, characterized in that: The parameters of the gamma ray irradiation treatment in step S4 include a dose rate of 0.5-0.8 kGy / min and an irradiation treatment time of 7-10 min.
6. A sterilization method for reducing the radiation sterilization dose of experimental animal feed according to claim 1, characterized in that: The low temperature treatment in step S5 is performed by burying the experimental animal feed product treated in step S4 in dry ice, and taking it out for later use when the temperature of the experimental animal feed product drops to -10°C.
7. A sterilization method for reducing the radiation sterilization dose of experimental animal feed according to claim 1, characterized in that: The three heat activation treatments in step S6 are carried out by water bath heating, and the experimental animal feed product treated in step S5 is immersed in a water bath at 80-82° C. for 50-60 minutes.
8. A sterilization method for reducing the radiation sterilization dose of experimental animal feed according to claim 1, characterized in that: The parameters of the secondary gamma ray irradiation treatment in step S7 include a dose rate of 1-1.5 kGy / min and an irradiation treatment time of 4-5 min.