Puffed grain for improving digestibility and method thereof

Abstract

The invention belongs to the technical field of animal food or animal food testing materials, and specifically relates to an expanded food for improving digestibility and a method thereof, comprising protein, lactic acid bacteria, lactic acid, and glucose, wherein the protein is crude protein, and baking soda can be added to the expanded food components. The preparation method of the pet feed of the invention is simple to operate, has a wide range of production raw materials, and has low cost, high nutritional value, is economical and practical, and has good market prospects. The food of the invention has the characteristics of convenient storage, convenient feeding, richer nutrition, easy eating, easy digestion, etc. The method of the invention is simple and easy to operate or the test is cheap to promote. The invention provides a digestion test method of a system or system. The evaluation method or evaluation material or evaluation agent of the invention can at least realize the evaluation or evaluation of the digestion and decomposition stage or whether the digestion is thorough or the digestion process or the quality of the protein digestion or decomposition result. The invention will contribute to the healthy and rapid development of pet food.

Description

Technical Field

[0001] The invention belongs to the technical field of animal grains or animal grain detection materials, and particularly relates to an expanded grain with improved digestibility and a method thereof. Background Art

[0002] Cats, dogs and other animals mainly use meat as an energy source, and the amino acids they absorb are mainly provided by animal protein and energy for rapid growth. Therefore, eating easily absorbed amino acid content protein cat and dog food can effectively change the current digestion of cats and dogs, which is beneficial to the healthy growth of cats, dogs and other animals. At present, most of the animal food on the market is prepared with high meat content or contains plant protein. Cats encounter this kind of high meat content food, which will produce fermentation peak or stickiness in the stomach, that is, rubbing the gastric mucosa or a large amount of high protein accumulation or plant protein at the end of the small intestine. A large amount of high meat protein or mixed plant protein leads to low digestibility of animals such as cats, dogs and fish, hurts the stomach and intestines, and can increase the burden on the cat's kidneys and cause kidney disease. The cat's kidneys are very important. They are mainly responsible for eliminating metabolites in the body and maintaining water and electrolyte balance. Excessive protein will increase the metabolic burden of the kidneys, which may cause kidney damage and disorders in the long run. Secondly, too much protein may also cause intestinal problems such as constipation, diarrhea, gastroenteritis, etc. After consuming too much high-protein meat or plant protein, part of it cannot be absorbed and will be excreted, which may cause intestinal burden; therefore, reducing high-protein meat such as pork, chicken, duck, beef, mutton, and goose, or mixed plant protein meat is beneficial to animal digestion and growth. In addition, the existing animal food lacks simple, cheap, or easy-to-operate evaluation methods or materials for the digestion process or digestion stage, and also lacks corresponding amino acid or peptide bond evaluation methods or materials. The existence of the above problems seriously restricts the healthy and rapid development of animal food. Summary of the invention

[0003] In order to solve one of the above problems, the present invention provides a puffed food with improved digestibility, comprising protein, lactic acid bacteria, lactic acid, glucose,

[0004] Preferably, the protein is fish protein or crude protein.

[0005] Preferably, baking soda or cicada pupae can be added to the puffed food components.

[0006] The present invention also provides a method for preparing puffed food with improved digestibility, comprising the following steps S1, naturally air-drying the fish protein, and then grinding and crushing it into powder;

[0007] S2. Mix 5 parts of lactic acid solution and 10 parts of glucose powder according to the mass ratio, add 0.5-1 parts of lactic acid bacteria and 50-80 parts of protein powder and stir evenly at room temperature to form a paste;

[0008] S3, adding 10-30 parts by weight of water to the paste in step S2, stirring evenly, putting into a grain block mold and freezing at -1 to 15°C to form a shaped grain block;

[0009] S4, drying the formed grain blocks at 60-120° C. and cooling them to form formed puffed grains;

[0010] S5. Test and package the puffed grain or crush and granulate it and then vacuum package it.

[0011] Furthermore, in step S3, 2-5 parts by mass of baking soda are added during the stirring process, and in step S3, 10-20 parts by mass of cicada pupa powder are added during the stirring process.

[0012] The present invention also provides an expanded grain or protein evaluation agent, which is formed by reacting allyl 2-amino-3-mercaptopropionic acid methyl ester hydrochloric acid, 2,3-dihydroxy-1-butene, allyl ammonium chloride or bentonite to form a substance containing the following structural formula I or structural formula II:

[0013]

[0014]

[0015] The invention also provides a method for preparing an expanded grain or protein evaluation agent, comprising the following steps: adding the bentonite, the allyl 2-amino-3-mercaptopropionic acid methyl ester hydrochloride, 2,3-dihydroxy-1-butene, allyl ammonium chloride and deionized water reaction components into a reactor in a mass ratio of 6:1:0.7:0.3:10 in sequence, stirring, adjusting the pH to 5.5-7, testing the viscosity and stirring at 40-60°C for 20 minutes, adding sodium persulfate and sodium sulfite, stirring and reacting at a constant temperature to obtain a viscous slurry, stopping the reaction when the viscosity of the tested slurry increases, and then drying the slurry and grinding it into a micron powder to form an evaluation agent for expanded grain digestion.

[0016] The present invention also provides a performance test method for puffed grain or protein evaluation agent, firstly, the expansion or suspension test: the evaluation agent solution is prepared with deionized water, and a base bentonite solution is prepared under the same conditions, the evaluation agent solution and the bentonite solution are added to a graduated flat-bottom test tube, stirred evenly, and the height of the expansion layer is observed at rest; secondly, the amino acid test: the amino acid amines constituting the protein are added to deionized water in a mass ratio of 1:1 to prepare an amino acid solution with a concentration of, the amino acid solution is added to the test tube, and the evaluation agent is added to each test tube and stirred evenly, after adjusting the acidity and alkalinity of the test tube, the expansion height is recorded, and each test tube is filtered to form a filtrate, and the content of the amino acid in the filtrate is measured to test the amino acid adsorption performance of the evaluation agent.

[0017] Furthermore, it also includes a copper ion test: a copper sulfate solution is prepared with deionized water, the copper sulfate solution is added into a test tube, 0.05 g is added to adjust the acidity and alkalinity of the test tube, and then the swelling height is recorded, each test tube is filtered to form a filtrate, and the content of divalent copper ions in the filtrate is tested to test the copper ion performance of the evaluation agent, and the corresponding swelling height can be used to evaluate the digestion and decomposition stage or the digestion process.

[0018] The present invention provides a method for evaluating and testing the decomposition of amino acids by proteins or the process of protein digestion or the digestibility of proteins. The first step is to weigh the puffed food and add it into a 300-500 ml flask, add 150-200 ml of a preheated 0.1-0.2% pepsin solution in equal mass ratio, cover the sealing plug, stir and digest at 45 degrees for 16 hours, filter and collect the filtrate after digestion, determine the protein content according to the Kjeldahl nitrogen test method, and calculate the digestibility of the pet food or protein;

[0019] In the second step, 10 ml of the filtrate in the first step is added to several corresponding graduated flat-bottom test tubes, 0.5 g of the evaluation agent is added to each test tube and stirred evenly, the pH of the test tube is adjusted to 5 and stirred evenly, and then left to stand for 3 hours, and the swelling height of 6 cm is recorded to test the amino acid content or evaluate the amino acid content or digestion quality based on the swelling height.

[0020] Beneficial effects of the present invention:

[0021] The preparation method of the pet feed of the present invention is simple to operate, has a wide range of production raw materials, and has low cost, high nutritional value, is economical and affordable, and has good market prospects. The food of the present invention has the characteristics of easy storage, convenient feeding, richer nutrition, easy eating, easy digestion, etc. The method of the present invention is simple and easy to operate or test, and is cheap to promote. The invention provides a system or systematic digestion test method.

[0022] The evaluation method, evaluation material or evaluation agent of the present invention can at least realize the evaluation of the reaction status of amino acids or the reaction status of copper ions, or the evaluation of the digestion and decomposition stage or whether the digestion is thorough, or the evaluation of the digestion process, or the basis for evaluating the quality of protein digestion or decomposition results, or the evaluation of the effect of one of the digestion results and processes. The present invention will contribute to the healthy and rapid development of animal food. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 : Infrared detection spectrum of animal food or protein evaluation agent;

[0024] Figure 2 : Electron micrograph of animal food or protein evaluation agent. DETAILED DESCRIPTION

[0025] A puffed food with improved digestibility: comprising protein, lactic acid bacteria, lactic acid, and glucose. Preferably, the protein is preferably fish protein or crude protein. Baking soda (not exceeding the amount specified for food, preferably 2%) can also be added to the puffed food component. Preferably, cicada pupae can also be added to the puffed food component. A method for preparing puffed food with improved digestibility,

[0026] S1. Dry the fish protein naturally, then grind it into protein powder of no less than 80 mesh, and further grind the cicada pupae into 80 mesh to make cicada pupae powder.

[0027] S2. Mix 5 parts of lactic acid solution and 10 parts of glucose powder according to the mass ratio, add 0.5-1 parts of lactic acid bacteria and 50-80 parts of protein powder and stir evenly at room temperature to form a paste;

[0028] S3, adding 10-30 parts by mass of water to the paste in step S2, stirring evenly, putting into a grain block mold (preferably with a specification of 3*3*2cm), freezing at -1 to 15°C for 12-36 hours to form a formed grain block;

[0029] S4, drying the formed grain blocks at 60-120° C. and cooling them to form formed puffed grains;

[0030] S5. Test and package the expanded grain or crush and granulate it and then vacuum package it.

[0031] Furthermore, the method further includes adding 2-5 parts by weight of baking soda in step S3 for stirring.

[0032] Furthermore, the method further comprises adding cicada pupa powder in a mass ratio of 10-20 parts by weight and stirring in step S3, wherein the cicada pupae can also be replaced by high-protein powder.

[0033] A puffed grain or protein evaluation agent or evaluation material, composed of the following substances: allyl 2-amino-3-mercaptopropionic acid methyl ester hydrochloric acid, 2,3-dihydroxy-1-butene, allyl ammonium chloride or bentonite react to form a substance containing the following structural formula I or structural formula II,

[0034]

[0035] A method for preparing an expanded grain or protein evaluation agent, wherein the evaluation agent is prepared by taking 120 g of 10-100 micron bentonite, preferably calcium-based, and sequentially mixing the calcium-based bentonite, the allyl 2-amino-3-mercaptopropionic acid methyl ester hydrochloride, and 2,3-dihydroxy-1-butene (CAS 497-06-3), allyl ammonium chloride (CAS10017-11-5), and deionized water reaction components are added to the reactor, stirred for 15 minutes, and the pH is adjusted to 5.5-7, preferably acidic. Preferably, 0.2g of ferrous chloride is added after the bentonite is added to adjust the binding degree or reaction degree. The viscosity is 5mpa.s with a six-speed viscometer, preferably 80 microns of calcium-based bentonite. After stirring at 40-60°C for 20 minutes, bromine water is dripped onto the bentonite particles after sampling and filtration. It is found that the bromine water fades, indicating that the reaction components are physically combined with the surface or interior of the bentonite. 3g of sodium persulfate and 3g of sodium sulfite are added, and the reaction is stirred at a constant temperature of 60°C for 30 minutes to obtain a viscous mud. The six-speed viscometer is used to test the mud viscosity. When it increases to 18mpa.s, the reaction is stopped, and then the mud is dried and ground into 30-40 micron powder to form an evaluation agent for the digestibility of puffed grains. The evaluation agent contains at least part of the substructure formula I as follows:

[0036]

[0037] Furthermore, the preparation method also includes the preparation of comparative evaluation agent 2, removing the bentonite in the above components, adding the allyl 2-amino-3-mercaptopropionic acid methyl ester hydrochloride, 2,3-dihydroxy-1-butene (CAS497-06-3), allyl ammonium chloride (CAS10017-11-5), and deionized water reaction components into the reactor in a mass ratio of 1:0.7:0.3:10, and using the same method as above to prepare a comparative evaluation agent 2 containing at least the following structural formula II, Furthermore, allyl 2-amino-3-mercaptopropionic acid methyl ester hydrochloride is prepared by adding 2-amino-3-mercaptopropionic acid methyl ester hydrochloride and 300 g of allyl chloride in a molar ratio of 1:2 in a 1L three-necked flask, and then adding 300 g of an aqueous solution containing 100 g of methanol solvent and stirring evenly. After the three-necked flask is configured with condensation reflux, the three-necked flask is sealed, heated at a constant temperature of 23-45°C, shaken for reaction for 24 hours, stirred at 45-80°C, and distilled under reduced pressure to a paste or crystal state, and dried in a blast drying oven at not less than 100°C for 6-8 hours to crush, and 3 g of the dried sample is dissolved in 20 g of water and then When 0.3-1 g of bromine water is added, large areas of bromine water fade, indicating that the target product, allyl 2-amino-3-mercaptopropionate methyl ester hydrochloride, is synthesized. The CAS number of the allyl chloride is 107-05-1), the CAS number of the 2-amino-3-mercaptopropionate methyl ester hydrochloride is 88806-98-8, and the agents not specifically described herein are preferably analytically pure, and the bentonite is preferably produced in Gansu. The above-mentioned 2-amino-3-mercaptopropionate methyl ester hydrochloride can be replaced by phosphoenolpyruvate monocyclohexyl ammonium salt, and the 2,3-dihydroxy-1-butene can be replaced by androstenediol.

[0038] The performance test method of the evaluation agent is first to perform a swelling or suspension test: 0.5% of the evaluation agent solution is prepared with deionized water, and 0.5% of the calcium-based bentonite solution is prepared under the same conditions. 10 ml of each of the evaluation agent solution and the calcium-based bentonite solution are added to a graduated flat-bottom test tube, stirred evenly, and then observed for the height of the swelling layer. The test result shows that the evaluation agent solution has a swelling height of 8 cm after 30 hours, while the calcium-based bentonite solution has a swelling height of 7 cm after 24 hours, indicating that the swelling and suspension properties of the evaluation agent are better than those of the calcium-based bentonite, and good suspension is conducive to sufficient contact reaction. Further, 0.01 g of borax is added to the suspension of the evaluation agent and the above evaluation agent test is repeated. The evaluation agent solution has a swelling height of 8 cm after 38 hours, indicating that borax is beneficial to increase the suspension time of the evaluation agent or better enable the evaluation agent to fully contact and react with the solution.

[0039] Secondly, the amino acid test: 20 common amino acid amines that make up proteins are added to deionized water in a mass ratio of 1:1 to prepare an amino acid solution with a concentration of 4%. Take no less than 3 portions of the amino acid solution (10 ml) and add them to the corresponding flat-bottom test tubes with scales. Add 0.05g of the evaluation agent to each test tube and stir evenly. After adjusting the acidity and alkalinity of the test tube, stir evenly and let it stand for 3 hours. After recording the swelling height, filter each test tube to form a filtrate. The amino acid content in the filtrate is determined by spectrophotometry to test the amino acid adsorption performance of the evaluation agent. The test results show that the evaluation agent can effectively adsorb amino acids under the condition of pH 4.5-5.5. After stabilization, the saturated amount of external adsorption in the solution is calculated to be 0.1g, corresponding to a swelling height of 6cm before filtration. Replace 0.05g of the evaluation agent in the above process with 0.05g of the comparative evaluation agent 2, and test under the same conditions. At pH 4. 5-5.5 conditions, the amount of amino acid adsorption was undetectable. It was analyzed that under the above conditions, the bentonite part in the evaluation agent mainly reflected the effect of adsorbing amino acids. After the adsorption of amino acids, the corresponding expansion of the bentonite was reduced to 6 cm. Further, the linear correlation test of expansion was performed: the 20 kinds of amino acids were added to deionized water in a mass ratio of 1:1 to prepare an amino acid solution with a concentration of 4%, and the concentration of amino acids was changed to 2% amino acid solution and 1% amino acid solution. The test results of the expansion height before filtration were repeated under the above conditions, which were 7.5 cm and 8.6 cm, respectively, indicating that there was a certain linear correlation between the amount of amino acids and the expansion height, that is, the greater the absorption, the smaller the expansion, indicating that the expansion height can correspond to the evaluation or provide a basis for the quality of protein digestion or decomposition results. In addition, in the above amino acid test process, the expansion effect of 40% concentration amino acids and 0.5g of the evaluation agent was consistent.

[0040] The third copper ion test: 0.02% copper sulfate solution was prepared with deionized water, and no less than 3 portions of 10 ml of the copper sulfate solution were added to several graduated flat-bottomed test tubes, and 0.05 g of the evaluation agent was added to each test tube and stirred evenly. After adjusting the acidity and alkalinity of the test tubes, the mixture was stirred evenly and left to stand for 3 hours. After recording the swelling height, each test tube was filtered to form a filtrate. The content of divalent copper ions in the filtrate was tested by atomic absorption spectrophotometry to test the copper ion performance of the evaluation agent. The test results showed that the evaluation agent could effectively adsorb copper ions only under pH 9.3-10.5. The filtrate contained 0.008 copper sulfate ions, corresponding to a swelling height of 7.6 cm before filtration, indicating that the unloaded bentonite also partially adsorbed copper under this condition. The organic part of the evaluation agent first absorbs and stabilizes, and then the bentonite part partially absorbs or exchanges. The corresponding swelling height can evaluate the test effect or the number of peptide bonds, or evaluate the digestion and decomposition stage or whether the digestion is thorough, or evaluate the digestion process. The comparative evaluation agent 2 is used instead of the evaluation agent to carry out the above copper ion test. The completed test result is that the filtrate contains 0.0083 copper sulfate ions. The evaluation agent 2 also absorbs most of the copper ions, but there is no swelling height, and the reaction time is much higher than that of the evaluation agent. This shows that the comparative evaluation agent 2 can test copper ions but cannot use the swelling height to evaluate the copper ions or digestion and decomposition. Further analysis shows that the organic-inorganic combination in the evaluation agent is beneficial to the absorption and exchange of copper from organic to inorganic; the adsorption in the amino acid test The evaluation agent after saturation filtration replaced the above 0.05g evaluation agent and tested copper ions under the same conditions, pH 9.3-10.5, and the filtrate contained 0.0076 copper ions, corresponding to the expansion height of 7.9cm before filtration, indicating that in this case, the evaluation agent bentonite part did not absorb copper significantly after saturation, and the corresponding evaluation agent did not expand significantly. If the evaluation agent was not saturated with amino acids and used for copper testing, the expansion height would decrease. Further, by the same linear correlation test of expansion, it was found that the absorption and expansion of copper by the evaluation agent also had a certain linear correlation, that is, the larger the absorption, the smaller the expansion; further, the evaluation agent after saturation filtration in the amino acid test was added to form 0.02% copper sulfate complexed with polypeptide or biuret The purple solution was adjusted to pH 9.3. After reacting for 3 hours, the purple color disappeared. After filtering the evaluation agent, burning the evaluation agent will produce ash. The burned ash and residue are rinsed in an aqueous solution. After filtering and separating the bentonite particles again, the filtrate liquid filtered again is dissolved in acid and then tested by atomic absorption. The calculation results show that the evaluation agent contains 0.1 copper sulfate by conversion, that is, the evaluation agent completely adsorbs the copper adsorbed by biuret, indicating that the stability of the complex copper of the evaluation agent under the above conditions is better than that of biuret; further, the copper ion test liquid of the ash solution after filtration can be replaced by the liquid obtained by heating the filtered evaluation agent with hydrogen peroxide to break the gel to test the copper ion. In the above test, 2% copper sulfate (converted to and the corresponding 0.5g evaluation agent expansion test result is consistent.

[0041] Evaluation agent identification, add excess copper sulfate to 100ml of 0.5% evaluation agent solution, adjust pH to 9.5, stir, add 0.1g borax, stir and stand for 3 hours, filter out the evaluation agent, perform infrared analysis and electron microscope analysis on the evaluation agent paraffin coating, preferably deionized water and chromatographic reagent or AR reagent are used for the above analysis. The specific results are as follows: infrared analysis of the evaluation agent paraffin coating is as follows: Figure 1 The peaks near 3620cm-1, 1032cm-1, 796cm-1, and 490cm-1 are the characteristic absorption of calcium-based benzophenone, the characteristic absorption between 3100cm-1 and 1430cm-1 is allyl ammonium chloride, and there is no obvious absorption between 1660-1645cm-1, which means the diluent bond is opened. The dihydroxy absorption peak at 3600cm-1, the infrared characteristic absorption of methyl propionate at around 1116cm-1 and 1748cm-1, and the sulfur hydrogen peak at 2500-2600cm-1 indicate that it contains at least a substance as shown in structural formula I. The peak at 630cm-1 is copper, and the micro-absorption peak at around 2100cm-1 is considered to be boron-related absorption.

[0042] Further evaluation of the electron microscopy images Figure 2 It can be seen that Figure 2 The pores in the flaky layer appeared in the analysis, which was considered to be the bentonite layer structure. The pores close to the bentonite layer structure were adhered with clustered lines, which were slightly thinner than the hydroxyl oxygen. The analysis showed that it was the copper complexed by methyl propionate hydrochloride in the evaluation agent. Two cross-thin lines appeared far outside the clustered line spots, which were considered to be the cross-linking or adsorption of 2 hydroxyl and boron, further confirming the appearance of structural formula I. In summary, the evaluation agent or evaluation material can at least realize the evaluation of the reaction of amino acids or the reaction of copper ions, or the evaluation of the digestion and decomposition stage or whether the digestion is thorough, or the evaluation of the digestion process, or the basis for evaluating the quality of protein digestion or decomposition results, or the evaluation of the effect of one of the digestion results and processes.

[0043] A method for evaluating the decomposition of amino acids in proteins or the process of protein digestion or the digestibility of proteins.

[0044] The first step is to weigh 0.5-1g of the puffed grain or other protein food of the present invention, preferably the puffed grain of the present invention for testing in this embodiment, preferably 1g, add it to a 300-500ml flask, add 150-200ml of preheated 0.1-0.2% pepsin solution in equal mass ratio, cover the sealing plug, stir and digest at 45 degrees for 16h, filter after digestion, preferably filter with an 80-mesh filter, collect the filtrate after rinsing, measure the rinsing amount, transfer the indigestible matter into a Kjeldahl flask to test the content of indigestible pro-protein, take another portion of the same puffed grain or other protein food, determine its protein content according to the Kjeldahl nitrogen test method, and calculate the digestibility of the pet food or protein. Further, after adding the protease, it also includes adding the trypsin or chymosin or aminopeptidase in equal mass ratio.

[0045] In the second step, 10 ml of the filtrate in the first step is added to several corresponding graduated flat-bottom test tubes, 0.5 g of the evaluation agent is added to each test tube and stirred evenly, the pH of the test tube is adjusted to 5, stirred evenly and then left to stand for 3 hours, and the swelling height is recorded as 6 cm, the amino content is tested, or the amino acid content or digestion quality is evaluated according to the swelling height. Specifically, the swelling height is less than 6, which is 40% or more, which is evaluated as excellent, the swelling height is 6-7.5, which is 30% or more, which is evaluated as medium, and the swelling height is higher than 7.5, which is less than 30, which is evaluated as poor. Therefore, the digestion result is evaluated as excellent, indicating that the digestion result of the puffed grain of the present invention is excellent (the amino acid content in the filtrate is determined by spectrophotometry, which is 40%, and the excellent content and evaluation are confirmed, indicating the reference of evaluating the protein digestion result by the evaluation agent swelling height method). Under the same conditions, the amino acid content of a certain C type of pet food in the above case does not exceed 40%, and the corresponding swelling height is higher than 6. Therefore, the puffed grain of the present invention helps to improve the digestibility.

[0046] The third step is to add 0.1% copper sulfate to the filtrate after the second step, adjust the pH to 7-8, and heat the reaction slightly until the purple color appears unchanged, then adjust the pH to 9.5, stir the reaction, and the purple disappears, indicating that the evaluation agent adsorbs or complexes the copper complexed by the polypeptide in the filtrate. According to the evaluation rules, the polypeptide content in the filtrate is less than 0.6%, indicating that the endonuclease hydrolysis of the protein peptide chain is in a better stage. Further, the purple disappears and the evaluation agent swells to a height of less than 6 after 3 hours of static, indicating that there are few polypeptides and copper sulfate is left. The evaluation agent has inorganic adsorption, which confirms that the endonuclease hydrolysis of the protein peptide chain is better, indicating that the endonuclease stage of the puffed grain of the present invention is completed. Excellent (the peptide bond content in the filtrate tested by 220nm ultraviolet light is also less than 0.6%, confirming the reference value of the above-mentioned evaluation of the hydrolysis stage or process of protein by color or swelling height); further, the pH of the solution after the swelling height test in the third step is adjusted to 7-8, and 0.1-1% of copper sulfate is added to the solution in the third step again, and the solution is slightly heated and stirred for reaction. When the purple color appears unchanged, the pH is adjusted to 9.5 again, and the reaction is stirred. If the purple color does not disappear, an evaluation agent is added or the purple color disappears after the evaluation agent is added, indicating that the polypeptide content exceeds 0.6%, indicating that the endonuclease hydrolysis stage of the protein peptide chain is not completed.

[0047] In addition, by feeding the puffed food of the present invention to healthy cats, dogs or fish for 2 weeks, the cats and dogs did not have digestive abnormalities, and the weight of the cats, dogs and fish increased significantly after 2 weeks.

[0048] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for evaluating the process of protein decomposition of amino acids or protein digestion in puffed grains, characterized in that: The first step is to weigh 1g of puffed grain and add it to a 300-500ml flask, add 150-200ml of preheated 0.1-0.2% pepsin solution, cover the sealing stopper, stir and digest at 45°C for 16h, filter and collect the filtrate after digestion, determine its protein content according to the Kjeldahl nitrogen test method, and calculate the digestibility of protein in the puffed grain; the second step is to take 10ml of the filtrate in the first step, add it to several corresponding scale flat-bottom test tubes, add 0.5g of evaluation agent to each test tube, stir evenly, adjust the pH of the test tube to 5, stir evenly, and then stand for 3 hours, record the swelling height, test the amino acid content or evaluate the amino acid content or digestion quality according to the swelling height; the preparation method of the evaluation agent comprises the following steps: Bentonite, allyl 2-amino-3-mercaptopropionic acid methyl ester hydrochloride, 2,3-dihydroxy-1-butene, allyl ammonium chloride and deionized water were added to the reactor in the mass ratio of 6:1:0.7:0.3:

10. After stirring, the pH was adjusted to 5.5-7. After the viscosity was tested, the mixture was stirred at 40-60°C for 20 minutes. Then, sodium persulfate and sodium sulfite were added and stirred at a constant temperature to react to obtain a viscous mud. When the viscosity of the mud increased, the reaction was stopped. Then, the mud was dried and ground into a micron powder to form an evaluation agent. The structure of the evaluation agent is as follows:

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