Pet food and method of making same

Abstract

The present application belongs to the technical field of pet feed, and particularly relates to a pet feed and a preparation method thereof. The present application is characterized in that hydrophobic modification is performed on chitosan, and a one-step method is used to graft palygorskite with the hydrophobically modified chitosan and surfactin, so as to obtain a novel feed additive. The pet feed prepared by adding the novel feed additive into a basic feed has excellent moisture-proof and antibacterial functions, is suitable for being placed in a pet feeding trough for a long time for free consumption by pets, and greatly reduces the pressure of pet keepers on pet feeding.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of pet feed, and particularly relates to a pet feed and a preparation method thereof. BACKGROUND

[0002] In recent years, with the highlighting of social problems such as aging, depopulation, and a sharp decline in the marriage rate, pet-keeping has become an emotional outlet in the lives of many people. Pet-keeping can bring companionship to the solitary population and help promote the physical and mental health of these groups. According to the 2020 pet industry white paper, pet dogs and cats are the first choice for pet-keeping in families. The pet economy has also become a very large trend, with huge market demand. Various services for pets have begun to appear in people's lives.

[0003] Due to the fast pace of modern society, most pet keepers need to feed their pets quickly when feeding them. Therefore, the pet feed industry has launched ready-made feed that can be quickly fed to cater to the needs of pet keepers. Most of the ready-made feed is dry pet feed. When feeding, pet keepers only need to place the ready-made feed in the pet feeding trough, without spending much time, thereby reducing the pressure on pet keepers when feeding pets. In order to prolong the storage time of the ready-made feed, additives that play a role in preventing corrosion, etc. are usually added to the ready-made feed.

[0004] However, this causes the pet feed to be in a completely exposed state to the air for a long time. On the one hand, microorganisms in the air are easy to enter the feed and reproduce using the nutrients in the feed. On the other hand, when the water vapor content in the air is high, the feed is also easy to absorb water, which further leads to the breeding of microorganisms. The reproduction of microorganisms can cause the pet food to have poor flavor and have a great impact on the health of pets.

[0005] Therefore, there is a need in the art for pet feed with moisture-proof and antibacterial functions. SUMMARY

[0006] In order to solve the above problems, the present application provides a pet feed comprising a basic feed and a feed additive, the feed additive being prepared as follows:

[0007] (1) Preparation of hydrophobically modified chitosan: chitosan is added to a mixed solution of carbonate and chloroalkane, methanesulfonic acid is added for amino protection, then hexadecanoyl chloride chloroalkane solution is slowly added, the reaction is continued for 5-6 hours, the temperature is raised to reflux for 10-12 hours, the reaction liquid is cooled to room temperature, filtered, then ammonia is added for deprotection, and hydrophobically modified chitosan is obtained after rotary evaporation;

[0008] (2) One-step method for grafting palygorskite: palygorskite, hydrophobically modified chitosan and surfactin are stirred in an alcohol solvent at 50-60℃ for 1-5 hours, and the hydrophobically modified chitosan and surfactin grafted palygorskite is obtained after filtration, washing and drying.

[0009] Further, the carbonate salt is selected from one or more of potassium carbonate, sodium carbonate or calcium carbonate.

[0010] Further, the chlorinated alkane is selected from dichloromethane, dichloroethane, trichloromethane or carbon tetrachloride.

[0011] Further, the degree of deacetylation DD of the chitosan is 70-90%, and the weight average molecular weight Mw is 100000-800000.

[0012] Further, the molar ratio of chitosan to acylating agent is 1:3-5.

[0013] Further, the volume ratio of carbonate salt to chlorinated alkane in the mixed solution of carbonate salt and chlorinated alkane is 2:1.

[0014] Further, the mass ratio of palygorskite, hydrophobically modified chitosan and surfactin is 10:4:1-2.

[0015] Further, the alcohol solvent is selected from methanol or ethanol.

[0016] As used herein, surfactin can be commercially available or can be obtained by fermentation, acid hydrolysis, drying and purification of Bacillus subtilis.

[0017] Further, the basal feed can be any basal feed known in the art for use as pet feed, and one skilled in the art is capable of selecting the composition of the basal feed according to the specific pet. For example, as employed in the examples of the present specification, the basal feed can comprise puffed corn meal, rice meal, wheat meal, corn protein meal, chicken meal, fish meal, choline chloride, chicken oil, soybean oil, fish oil and vitamins and minerals.

[0018] Further, the pet feed comprises 2-5 wt% of the feed additive.

[0019] The present application also provides a method for preparing a pet feed as described herein, which comprises mixing a basal feed and a feed additive in a mixer until uniform, to obtain the pet feed, wherein the feed additive is prepared by the preparation steps as described above.

[0020] Advantages of the present application

[0021] Attapulgite is a new type of additive for feed in recent years, which has no toxicity to animals and has multiple functions, including promoting the metabolism of animal body, improving the conversion rate of feed, making animals have a strong appetite, and providing trace elements necessary for growth. However, attapulgite has strong water absorption, which can cause feed to absorb moisture and deteriorate when applied to finished pet feed exposed to air for a long time, affecting the flavor.

[0022] Chitosan is a new type of green feed additive, which has a wide application in the feed industry. Chitosan is a broad-spectrum antibacterial substance, which has a certain inhibitory effect on bacteria and fungi. However, chitosan also has strong water absorption, which is not suitable for long-term exposure to air in finished pet feed.

[0023] Surfactin is a kind of antibacterial peptide mainly produced by gram-positive bacillus, which can exert broad-spectrum antibacterial effect by dissolving and destroying cell membrane.

[0024] In order to obtain pet feed with moisture-proof and antibacterial functions, the chitosan is hydrophobically modified in the application, and the attapulgite is grafted with hydrophobically modified chitosan and surfactin by one-step method. On the one hand, the hydrophobic side chain of hydrophobically modified chitosan and the hydrophobic head group of surfactin are exposed on the surface of attapulgite, which repels water and plays a role in moisture-proof. On the other hand, the good ion exchange, physical adsorption and specific surface area of attapulgite can make the antibacterial agent, i.e. hydrophobically modified chitosan and surfactin, well dispersed in the basic feed, and improve the antibacterial effect. DETAILED DESCRIPTION

[0025] The application will be further described below in combination with specific examples, but the examples do not limit the application in any form. Unless otherwise specified, the reagents, methods and equipment used in the application are conventional reagents, methods and equipment in the technical field.

[0026] Example 1

[0027] The pet feed is obtained by uniformly mixing the basic feed and the feed additive in a mixer and then granulating and drying, wherein the pet feed contains 4wt% of the feed additive.

[0028] The basic feed contains 20 parts of puffed corn powder, 25 parts of rice powder, 6 parts of rice powder, 18 parts of corn protein powder, 20 parts of chicken powder, 3 parts of fish powder, 10 parts of choline chloride, 5 parts of chicken oil, 1 part of soybean oil, 2 parts of fish oil, and 20 parts of vitamins and minerals.

[0029] The feed additive is prepared as follows:

[0030] (1) Preparation of hydrophobically modified chitosan: 3.5 g of chitosan with a degree of deacetylation of 85% and a weight average molecular weight of 300000 was added to a 200 ml mixed solution of sodium carbonate and chloroform (mass ratio of 2:1), 50 ml of methane sulfonic acid was added for amino protection, then 23 g of hexadecanoyl chloride dissolved in 40 ml of chloroform was slowly added dropwise, the reaction was continued for 5 hours, and the temperature was raised to reflux for 10 hours. The reaction liquid was cooled to room temperature, filtered, then ammonia was added for deprotection, and hydrophobically modified chitosan was obtained after rotary evaporation;

[0031] (2) One-step method for grafting attapulgite: Attapulgite, hydrophobically modified chitosan and surfactin (purchased from Sigma, CAS No. 24730-31-2) with a mass ratio of 10:4:1 were stirred in ethanol at 50°C for 5 hours, then filtered, washed repeatedly with distilled water and ethanol, and dried to obtain attapulgite grafted with hydrophobically modified chitosan and surfactin.

[0032] Example 2

[0033] The present example provides a pet feed which is obtained by uniformly mixing a base feed and a feed additive in a mixer and then granulating and drying, wherein the pet feed contains 2 wt% of the feed additive.

[0034] The base feed contains 20 parts of puffed corn flour, 25 parts of rice flour, 6 parts of rice flour, 18 parts of corn protein powder, 20 parts of chicken meal, 3 parts of fish meal, 10 parts of choline chloride, 5 parts of chicken oil, 1 part of soybean oil, 2 parts of fish oil, and 20 parts of vitamins and minerals.

[0035] The feed additive is prepared as follows:

[0036] (1) Preparation of hydrophobically modified chitosan: 3.5 g of chitosan with a degree of deacetylation of 85% and a weight average molecular weight of 300000 was added to a 200 ml mixed solution of sodium carbonate and chloroform (mass ratio of 2:1), 50 ml of methane sulfonic acid was added for amino protection, then 23 g of hexadecanoyl chloride dissolved in 40 ml of chloroform was slowly added dropwise, the reaction was continued for 5 hours, and the temperature was raised to reflux for 10 hours. The reaction liquid was cooled to room temperature, filtered, then ammonia was added for deprotection, and hydrophobically modified chitosan was obtained after rotary evaporation;

[0037] (2) One-step method for grafting attapulgite: Attapulgite, hydrophobically modified chitosan and surfactin (purchased from Sigma, CAS No. 24730-31-2) with a mass ratio of 10:4:1 were stirred in ethanol at 50°C for 5 hours, then filtered, washed repeatedly with distilled water and ethanol, and dried to obtain attapulgite grafted with hydrophobically modified chitosan and surfactin.

[0038] Comparative Example 1

[0039] The present comparative example provides a pet feed which is different from the pet feed of Example 1 in that, in the preparation process of the feed additive, no surfactin is used (10:5 attapulgite, hydrophobically modified chitosan is used), and the rest is the same as Example 1.

[0040] Comparative Example 2

[0041] The present comparative example provides a pet feed which is different from the pet feed of Example 1 in that, in the preparation process of the feed additive, no hydrophobically modified chitosan is used (10:5 attapulgite, surfactin is used), and the rest is the same as Example 1.

[0042] Comparative Example 3

[0043] The present comparative example provides a pet feed which is different from the pet feed of Example 1 in that, in the preparation process of the feed additive, no hydrophobically modified chitosan is used (10:5 attapulgite, surfactin is used), and the rest is the same as Example 1.

[0044] Comparative Example 4

[0045] The present comparative example provides a pet feed which is different from the pet feed of Example 1 in that, in the preparation process of the feed additive, no attapulgite is used, but the hydrophobically modified chitosan and the surfactin are directly mixed in a mass ratio of 4:1 to obtain the feed additive, and the rest is the same as Example 1.

[0046] Comparative Example 5

[0047] The present comparative example provides a pet feed which is different from the pet feed of Example 1 in that, in the preparation process of the feed additive, the mass ratio of attapulgite, hydrophobically modified chitosan and surfactin is 10:4:3, and the rest is the same as Example 1.

[0048] Comparative Example 6

[0049] The present comparative example provides a pet feed which is different from the pet feed of Example 1 in that, in the preparation process of the feed additive, the mass ratio of attapulgite, hydrophobically modified chitosan and surfactin is 10:4:0.5, and the rest is the same as Example 1.

[0050] Comparative Example 7

[0051] The present comparative example provides a pet feed which is different from the pet feed of Example 1 in that, in the preparation process of the feed additive, the attapulgite, the hydrophobically modified chitosan and the surfactin are not subjected to grafting reaction but are uniformly mixed together, and the rest is the same as Example 1.

[0052] Performance detection test

[0053] 1. According to GB4789.2-2010, the total number of colonies of the pet food samples prepared in Examples 1-2 and Comparative Examples 1-7 was detected.

[0054] 2. According to GB4789.3-2010, the number of coliform bacteria of the pet food samples prepared in Examples 1-2 and Comparative Examples 1-7 was recorded.

[0055] 3. The pet food samples prepared in Examples 1-2 and Comparative Examples 1-7 were placed in open air at normal temperature and pressure for 15 days and 30 days, respectively, and the total number of colonies and the number of coliform bacteria were detected, and the mass before and after drying was weighed, and the percentage change in mass was calculated to determine the moisture resistance of the pet food samples.

[0056] The test results are shown in Table 1 below.

[0057] Table 1

[0058]

[0059] As can be seen from the results in Table 1, when surfactin is not used (Comparative Example 1), the moisture resistance of the pet food is enhanced compared to Example 1, but the antibacterial property is weakened; and when the hydrophobically modified chitosan is not used (Comparative Example 2), the antibacterial property of the pet food is enhanced compared to Example 1, but the moisture resistance is weakened. Such results show that the hydrophobically modified chitosan and surfactin used in the present application are indispensable in order to achieve comprehensive performance improvement in moisture resistance and antibacterial property.

[0060] When the chitosan is not hydrophobically modified (Comparative Example 3), the moisture resistance of the pet food is significantly weakened compared to Example 1, and the antibacterial property is also weakened. This shows that the hydrophobically modified chitosan used in the present application is crucial for enhancing the moisture resistance of the pet food.

[0061] When attapulgite is not used (Comparative Example 4), the moisture resistance and antibacterial property of the pet food are both weakened compared to Example 1. This shows that attapulgite is very important for improving the dispersibility of the hydrophobically modified chitosan and surfactin in the base feed and for exerting their corresponding functions.

[0062] When the mass ratio of surfactin in the feed additive is increased (Comparative Example 5), the antibacterial property of the pet food is improved compared to Example 1, but the moisture resistance is weakened; and when the mass ratio of surfactin in the feed additive is reduced (Comparative Example 6), the moisture resistance of the pet food is improved compared to Example 1, but the antibacterial property is weakened. This shows that the specific mass ratio of the hydrophobically modified chitosan and surfactin used in the present application is very important in order to achieve comprehensive performance improvement in moisture resistance and antibacterial property.

[0063] When the attapulgite was not grafted, but the attapulgite, the hydrophobically modified chitosan and the surfactin were mixed together (Comparative Example 7), the moisture resistance and the antibacterial property of the pet feed were both weakened compared with Example 1. This shows that grafting the hydrophobically modified chitosan and the surfactin on the attapulgite is very important for optimizing the improvement of the dispersibility of the hydrophobically modified chitosan and the surfactin in the base feed and the exertion of their respective functions.

[0064] It should be noted that the preferred embodiments of the present application are given in the specification of the present application, but the present application can be realized in many different forms and is not limited to the embodiments described in the specification, and these embodiments are not intended to be additional limitations on the content of the present application, and the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive. Furthermore, the above technical features continue to be combined with each other, forming various embodiments not listed above, which are all considered to be within the scope of the present application; further, for those skilled in the art, the above description can be improved or transformed, and all these improvements and transformations should be within the protection scope of the claims of the present application.

Claims

1. A pet food, characterized by, The pet feed comprises a basal feed and a feed additive, which is prepared by: (1) Preparation of hydrophobically modified chitosan: chitosan is added into a mixed solution of carbonate and chloroalkane, methane sulfonic acid is added for amino protection, then a chloroalkane solution of hexadecanoyl chloride is slowly added dropwise, the reaction is continued for 5-6 hours, the temperature is raised to reflux for 10-12 hours, the reaction solution is cooled to room temperature, filtered, then ammonia is added for deprotection, and hydrophobically modified chitosan is obtained after rotary evaporation; (2) One-step method for grafting attapulgite: attapulgite, hydrophobically modified chitosan and surfactin are stirred in an alcohol solvent at 50-60℃ for 1-5 hours, and after filtration, washing and drying, attapulgite grafted and modified by hydrophobically modified chitosan and surfactin is obtained; The basal feed comprises puffed corn powder, rice powder, wheat powder, corn protein powder, chicken meal, fish meal, choline chloride, chicken oil, soybean oil, fish oil and vitamins and minerals.

2. The pet food according to claim 1, characterized in that, The carbonate is selected from one or more of potassium carbonate, sodium carbonate or calcium carbonate.

3. The pet food according to claim 1, wherein The chloroalkane is selected from dichloromethane, dichloroethane, trichloromethane or carbon tetrachloride.

4. The pet food of claim 1, wherein The degree of deacetylation DD of the chitosan is 70-90%, and the weight average molecular weight Mw is 100000-800000.

5. The pet food of claim 1, wherein The molar ratio of chitosan to acylating agent is 1:3-5.

6. The pet food of claim 1, wherein The volume ratio of carbonate to chloroalkane in the mixed solution of carbonate and chloroalkane is 2:

1.

7. The pet food of claim 1, wherein The mass ratio of attapulgite, hydrophobically modified chitosan and surfactin is 10:4:1-2.

8. The pet food of claim 1, wherein The alcohol solvent is selected from methanol or ethanol.

9. The pet food of claim 1, wherein The pet feed comprises 2-5wt% of the feed additive.

10. A method of preparing a pet food according to any one of claims 1 to 9, characterized in that, The pet feed is prepared by uniformly mixing the basal feed and the feed additive in a mixer. The pet feed is prepared by uniformly mixing the basal feed and the feed additive in a mixer.

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