Treating method and system for mycoprotein mash and application of treating method and system

Abstract

The invention relates to the technical field of treatment of thallus mash, in particular to a treatment method and system of thallus protein mash and application of the treatment method and system. The treatment method comprises the following steps: carrying out vacuum concentration on mycoprotein mash to obtain concentrated protein mash; carrying out wall breaking treatment on the concentrated protein mash to obtain concentrated protein mash containing thallus fragments; carrying out neutralization reaction on the concentrated protein mash by using an alkaline solution to obtain a concentrated protein reaction solution; sequentially carrying out enzymolysis reaction and enzyme deactivation treatment on the concentrated protein reaction solution by using a compound enzyme system to obtain a proteolysis reaction solution; wherein the compound enzyme system comprises the following raw materials: lysozyme, alkaline protease, nuclease and flavourzyme; and carrying out purification treatment on the proteolysis reaction liquid to obtain the mycoprotein treatment liquid. According to the treatment method, operations such as vacuum treatment, wall breaking treatment, neutralization reaction treatment and enzymolysis reaction are combined, and the content of peptide substances in the mycoprotein mash is effectively increased to 25% or above.

Description

Technical Field

[0001] The present application relates to the technical field of bacterial mash processing, and in particular to a bacterial protein mash processing method and system and application thereof. Background Art

[0002] At present, unconventional protein resources such as biological bacterial protein can be used as alternative resources for protein feed sources. Among them, the technology of producing ethanol Clostridium protein by biofermentation using carbon-containing gas as raw material can not only achieve effective substitution of protein feed, but also resource utilization of carbon-containing industrial tail gas resources. These technologies are effective measures to implement green and low-carbon development and new quality productivity. Existing studies have shown that ethanol Clostridium bacterial protein has the following characteristics: crude protein weight content ≥ 80%, amino acid protein ratio above 90%, complete amino acid variety and good balance, easy animal digestion and absorption, etc., and the bacterial protein has also been demonstrated for the safety, effectiveness and environmental friendliness of microorganisms and feed products, and is currently widely used in aquatic products, piglets and poultry feed. However, there are several problems in the production process and application of ethanol Clostridium protein:

[0003] (1) The water consumption of the ethanol Clostridium protein production process is relatively large, the proportion of recycled water used in the fermentation system is limited, and the wastewater treatment section is heavily burdened. In addition to bacterial protein, the distilled protein mash also contains bacterial metabolites such as acetic acid (about 5% by mass), phosphoric acid (about 0.05% by mass), and lactic acid (about 0.01% by mass). Although acetic acid and lactic acid can be used as acidifiers, and phosphoric acid can be used as a phosphorus source supplement, these acidifiers and phosphorus source supplements can be used in aquatic feed. However, at present, the culture medium after recovering bacterial protein from protein mash will be directly treated as wastewater, which undoubtedly causes a waste of biological resources;

[0004] (2) Ethanol Clostridium protein cannot be completely recovered and the production energy consumption is high. Since the cell size of ethanol Clostridium is small (average size is 0.5×3.2μm) and the mass concentration is low (less than 16g / L), the cell protein in the cell protein mash is currently mainly recovered by centrifugation and spray drying. However, centrifugation will cause the loss of some cell protein or free amino acids. In addition, the power consumption and steam consumption of spray drying are high, and the drying cost is high.

[0005] (3) The particle size of ethanol Clostridium protein is too low. Although ethanol bacteria will adhere to each other during the spray drying process, which will improve the particle size distribution of the bacterial protein product to a certain extent, the particle size of the bacterial protein product after spray drying is still relatively low (90% exceeds 300 mesh), and dust is easily formed in the subsequent batching process, posing safety and health risks;

[0006] (4) The ethanolic Clostridium protein has a strong taste. Since the ethanolic Clostridium produces miscellaneous acids and fusel alcohols during its bacterial metabolism, these miscellaneous acids and fusel alcohols will form a special odor in the exhaust gas during the spray drying process. This special odor will affect the surrounding environment, and the final bacterial protein powder will also have a special odor. When added in high amounts in animal feed, this special odor will affect the animal's feed intake;

[0007] (5) The processing and nutritional properties of ethanolic Clostridium protein cannot be fully released. Ethanol Clostridium is a Gram-positive bacterium, and its cell wall is mainly composed of peptidoglycan, which has strong mechanical strength and anti-degradation ability, limiting the high viscosity characteristics of ethanolic Clostridium protein. In addition, ethanolic Clostridium protein also contains 6.5% nucleic acid by mass. Although nucleic acid can be directly digested and absorbed by animals, the utilization efficiency of nucleic acid is low. In addition, although ethanolic Clostridium protein contains a large amount of bioactive peptides, these bioactive peptides have antioxidant, blood pressure lowering, blood sugar lowering and other properties, but because there is no enzyme system for directional enzymatic hydrolysis reaction in the animal body, these bioactive peptides cannot effectively play their own role.

[0008] In view of the above-mentioned defects of Clostridium ethanolate protein, at this stage, the protein mash containing Clostridium ethanolate protein can be subjected to efficient enzymatic hydrolysis reaction treatment to fully release the peptide substances in the protein mash. However, the content of peptide substances released at this stage is low, which will cause a waste of Clostridium ethanolate protein resources.

[0009] At present, the efficient enzymatic hydrolysis treatment technologies for protein mash containing ethanol Clostridium protein are:

[0010] (1) A method and system for treating industrial tail gas fermentation mash, wherein small peptide products can be obtained by homogenizing, enzymatically hydrolyzing, distilling and drying the fermentation mash; (2) A method for treating amino acid fermentation mash, wherein ultrasonic waves are used to denature the bacteria in the fermentation mash containing amino acids, and then solid-liquid separation is performed on the denatured mixture. Summary of the invention

[0011] The present application provides a method and system for processing bacterial protein mash and application thereof to solve the following technical problem: how to increase the content of peptide substances in ethanol Clostridium protein.

[0012] In a first aspect, the present application provides a method for treating bacterial protein mash, the method comprising:

[0013] The bacterial protein mash is vacuum concentrated to obtain concentrated protein mash;

[0014] The concentrated protein mash is subjected to cell wall breaking treatment to obtain a concentrated protein mash containing bacterial fragments;

[0015] Using an alkaline solution to neutralize the concentrated protein mash containing bacterial fragments to obtain a concentrated protein reaction solution;

[0016] The concentrated protein reaction liquid is subjected to enzymatic hydrolysis and enzyme inactivation treatment in sequence using a composite enzyme system to obtain a proteolytic reaction liquid; wherein the raw materials of the composite enzyme system include lysozyme, alkaline protease, nuclease and flavor protease;

[0017] The proteolysis reaction solution is purified to obtain a bacterial protein treatment solution.

[0018] Optionally, the mass m1 of the lysozyme, the mass m2 of the alkaline protease, the mass m3 of the nuclease and the mass m4 of the flavor protease satisfy the relationship: m1:m2:m3:m4≥1:1:1:1.

[0019] Optionally, the mass m2 of the alkaline protease, the mass m4 of the flavor protease and the weight m5 of the dry matter of the concentrated protein reaction solution satisfy the relationship: (m2+m4) / m5=(1-7):100.

[0020] Optionally, the temperature of the enzymatic hydrolysis reaction is 30°C to 50°C, and the time of the enzymatic hydrolysis reaction is 3h to 7h; and / or

[0021] The temperature of the enzyme inactivation treatment is 70° C. to 100° C., and the time of the enzyme inactivation treatment is 5 min to 10 min.

[0022] Optionally, the pressure of the vacuum concentration is 0.07 MPa to 0.09 MPa, and the temperature of the vacuum concentration is 30° C. to 70° C.; and / or

[0023] The mass concentration of bacterial protein in the concentrated protein mash is 60 g / L to 80 g / L.

[0024] Optionally, the pressure of the wall breaking treatment is 40MPa to 150MPa; and / or

[0025] The end point acid-base of the neutralization reaction is 9-11.

[0026] Optionally, the proteolysis reaction solution is purified to obtain a bacterial protein treatment solution, comprising the steps of:

[0027] Filtering the protein hydrolysis reaction solution to obtain a protein filtrate;

[0028] Desalting the protein filtrate to obtain a desalted protein solution;

[0029] The desalted protein solution is subjected to vacuum concentration using a composite gas and an adsorbent material to obtain a desalted protein concentrate;

[0030] The desalted protein concentrate is sterilized to obtain a bacterial protein treated solution.

[0031] Optionally, the composite gas includes carbon dioxide and / or nitrogen; when the composite gas includes carbon dioxide, the input flow rate of the carbon dioxide is 1% to 5% of the total flow rate of the composite gas; when the composite gas includes nitrogen, the input flow rate of the nitrogen is 1% to 5% of the total flow rate of the composite gas; and / or

[0032] The mass m6 of the adsorption material and the mass m7 of the desalted protein solution satisfy the relationship: m6:m7≥1:100.

[0033] In a second aspect, the present application provides a system for processing bacterial protein mash, the system being adapted to the processing method described in the first aspect, and the processing system comprising:

[0034] A first vacuum concentration system comprises a bacterial protein mash buffer tank, a first vacuum concentration device and a concentrated protein mash buffer tank, wherein the discharge port of the bacterial protein mash buffer tank is connected to the feed port of the first vacuum concentration device, and the discharge port of the first vacuum concentration device is connected to the concentrated protein mash buffer tank;

[0035] A high-pressure homogenizer, wherein the discharge port of the concentrated protein mash buffer tank is connected to the feed port of the high-pressure homogenizer to achieve a wall-breaking treatment of the concentrated protein mash;

[0036] An enzymolysis system comprises a batching tank, an alkali solution feeding pipe and an enzymolysis tank, wherein the feeding port of the batching tank is connected to the discharging port of the high-pressure homogenizer, the discharging port of the batching tank is connected to the feeding port of the enzymolysis tank, and the discharging port of the alkali solution feeding pipe is connected to the liquid inlet of the enzymolysis tank, so that the concentrated protein mash undergoes a neutralization reaction and an enzymolysis reaction to obtain a protein hydrolysis reaction liquid;

[0037] The purification treatment section is connected to the discharge port of the enzymolysis tank to purify the protein hydrolysis reaction liquid to obtain a bacterial protein treatment liquid.

[0038] Optionally, the purification treatment unit includes: a filter, an electrodialysis system, a second vacuum concentration system and a sterilization device;

[0039] The feed inlet of the filter is connected to the discharge outlet of the enzymolysis tank;

[0040] The electrodialysis system comprises an electrodialysis device and a desalting solution temporary storage tank, wherein the feed port of the electrodialysis device is connected to the feed port of the filter, so that the protein hydrolysis reaction liquid is desalted to obtain a desalted protein solution; the feed port of the desalting solution temporary storage tank is connected to the feed port of the electrodialysis device to store the desalted protein solution;

[0041] The second vacuum concentrating system includes a second vacuum concentrating device, a gas conduit, an adsorption material feed pipe and a desalted protein material tank. The feed port of the second vacuum concentrating device is connected to the discharge port of the electrodialysis device, the gas conduit is connected to the gas inlet of the second vacuum concentrating device, the adsorption material feed pipe is connected to the feed port of the second vacuum concentrating device, and the feed port of the desalted protein material tank is connected to the discharge port of the second vacuum concentrating device; the discharge port of the desalted protein material tank is connected to the sterilization device to sterilize the desalted protein concentrate.

[0042] In a third aspect, the present application provides an expanded floating feed, which includes a bacterial protein processing liquid obtained by the processing method described in the first aspect.

[0043] Optionally, in terms of weight, the raw materials of the puffed floating feed include 8 to 28 parts of the bacterial protein treatment liquid, 20 to 30 parts of fish meal, 53 to 56 parts of solid additives, 8.5 to 9.0 parts of compound oil, 1.4 to 2.2 parts of auxiliary materials, and ≥1 part of premix.

[0044] In a fourth aspect, the present application provides a method for preparing the expanded floating feed according to the third aspect, the method comprising:

[0045] The fish meal, the solid additive, the compound oil, the auxiliary materials and the premix are mixed to obtain a solid matrix;

[0046] The bacterial protein treatment liquid obtained by the treatment method described in the first aspect is subjected to a first conditioning using a solvent to obtain a liquid phase matrix;

[0047] Mixing the liquid matrix and the solid matrix to obtain a mixed raw material;

[0048] The mixed raw material is subjected to a second conditioning to obtain a feed raw material;

[0049] The feed raw materials are sequentially extruded, dried and sprayed with oil to obtain expanded floating feed particles.

[0050] Optionally, the mass m8 of the bacterial protein treatment solution and the mass m9 of the solvent satisfy the relationship: m8:m9=(8-28):(17.25-7.36); and / or

[0051] The mass of the solvent of the liquid phase matrix is ​​less than or equal to 70% of the mass of the liquid phase matrix.

[0052] Optionally, the temperature of the second tempering is 90° C. to 95° C., and the time of the second tempering is 8 min to 12 min; and / or

[0053] The extrusion temperature is 120°C to 150°C, and the extrusion pressure is 3MPa to 5MPa; and / or

[0054] The drying temperature is 95° C. to 103° C., and the drying time is 1 h to 2 h.

[0055] The above technical solution provided by the embodiment of the present application has the following advantages compared with the prior art:

[0056] The present application provides a method for treating bacterial protein mash, which first enriches the bacterial cells of the bacterial protein mash into a concentrated protein mash with a high bacterial cell concentration by vacuum concentration, and then performs a cell wall breaking treatment on the concentrated protein mash with a high bacterial cell concentration, so that the bacterial cells of the concentrated protein mash can be fully broken, so that the bacterial protein and other nutrients in the bacterial cells are released, and the cell wall breaking treatment can also evenly disperse the bacterial protein and other nutrients in the concentrated protein mash, and the evenly distributed concentrated protein mash is subjected to a neutralization reaction treatment with an alkaline solution, so that the concentrated protein mash is in an alkaline environment. environment, and the concentrated protein mash in an alkaline environment can promote the bacterial protein to enter the liquid phase system to obtain a concentrated protein reaction liquid with a high bacterial protein content; in addition, the concentrated protein reaction liquid is subjected to an enzymatic hydrolysis reaction using a composite enzyme system including lysozyme, alkaline protease, nuclease and flavor protease, which can convert most of the bacterial protein into a variety of bioactive peptides, and finally the process of the enzymatic hydrolysis reaction is terminated by inactivation treatment, and then the bioactive peptides generated by the enzymatic hydrolysis reaction and a small part of the bacterial protein can be separated from the concentrated protein reaction liquid by purification treatment, thereby obtaining a bacterial protein treatment liquid containing a large amount of peptide substances. Therefore, this treatment method combines vacuum treatment, wall breaking treatment, neutralization reaction treatment and enzymatic hydrolysis reaction, which can effectively increase the content of peptide substances in the bacterial protein mash. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0058] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0059] Figure 1 A schematic flow chart of a method for treating bacterial protein mash provided in an embodiment of the present application;

[0060] Figure 2 A detailed schematic diagram of a method for treating bacterial protein mash provided in an embodiment of the present application;

[0061] Figure 3 A schematic diagram of the logical structure of a bacterial protein mash processing system provided in an embodiment of the present application;

[0062] Figure 4 A schematic diagram of the actual structure of a bacterial protein mash processing system provided in an embodiment of the present application;

[0063] Figure 5 A schematic flow chart of a method for preparing puffed floating feed provided in an embodiment of the present application;

[0064] Among them, 1-the first vacuum concentration system, 11-the bacterial protein mash buffer tank, 12-the first vacuum concentration device, 13-the concentrated protein mash buffer tank, 2-the high-pressure homogenizer, 3-the enzymatic hydrolysis system, 31-the batching tank, 32-the enzymatic hydrolysis tank, 33-the alkali solution feed pipe, 4-the filter, 5-the electrodialysis system, 51-the electrodialysis device, 52-the desalted liquid temporary storage tank, 6-the second vacuum concentration system, 61-the second vacuum concentration device, 62-the gas duct, 63-the adsorption material feed pipe, 64-the desalted protein material tank, 7-the sterilization device. DETAILED DESCRIPTION

[0065] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0066] Various embodiments of the present application may be presented in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity and should not be understood as a rigid limitation on the scope of the present application; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and single numerical values ​​within the range; for example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which applies regardless of the range; in addition, whenever a numerical range is indicated in this document, it is meant to include any cited number (fractional or integer) within the indicated range.

[0067] In this document, the terms including "including" and "including" mean "including but not limited to". Relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. "And / or" describes the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone; where A and B can be singular or plural. "At least one" means one or more, and "plurality" means two or more; "at least one", "at least one of the following" or similar expressions, refers to any combination of these items, including any combination of single or plural items; for example, "at least one of a, b, or c", or "at least one of a, b, and c" can all mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple. "Parts" such as parts by weight and parts by mass indicate the proportional relationship between the components. In the proportional relationship involved in this article, the parameters that need to be described by proportion should be understood as the first term of the proportional formula in the order of description, and the proportional numbers should be understood as the second term of the proportional formula. For example, if the mass ratio of substance A, substance B and substance C is 1:2:3, then substance A, substance B and substance C should correspond to the proportional numbers in the proportional formula in the order of description, that is, the mass of substance A: the mass of substance B: the mass of substance C = 1:2:3.

[0068] It should be noted that all directional indications in the embodiments of the present application, such as up, down, left, right, front, back, etc., are only used to explain a certain specific posture (such as the relative position relationship and movement status of the various components shown in the accompanying drawings. If the specific posture changes, the directional indication will also change accordingly).

[0069] In this application, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection, a mechanical connection, an electrical connection, or a magnetic connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0070] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in this article can be purchased from the market or prepared by existing methods.

[0071] It should be noted that, with respect to the prior art (1) of the background technology, the inventors found that: this technology did not take into account that the high viscosity of the small peptide product would have a negative impact on the distillation system and the utilization of other effective ingredients in the fermentation mash. In addition, the solubility of bacterial protein under acidic conditions is low, and the efficiency of the enzymatic hydrolysis reaction is low; and with respect to the prior art (2) of the background technology, the inventors found that: the energy consumption of the ultrasonic treatment method used in this technology is usually high.

[0072] In addition, the fish feed used at present is mainly for herbivorous fish, so it contains a large amount of sugar, while carnivorous fish have limited metabolic capacity for sugar, so the amount of starch added to the feed for carnivorous fish needs to be reduced as much as possible, but at present, most fish feed uses puffed floating feed, and starch plays a role of adhesive in the processing of puffed floating feed. Too low starch content will lead to a decrease in the adhesiveness and physical quality of the feed, and will also reduce the puffing rate and dissolution rate of the feed. For example, the prior art: a preparation method of low-starch puffed floating feed, based on the advantages of high water absorption and high viscosity of ethanol clostridium protein, ethanol clostridium protein replaces the starch of fish feed, which can significantly reduce the dependence of fish feed on starch during the processing, but the technology needs to increase the conditioning moisture of fish feed to 27% to 30%, and also needs to increase the unit mechanical energy consumption input of fish feed in the drying stage to 10.27kJ / kg to 14.61kJ / kg, which undoubtedly increases the energy consumption of drying, thereby increasing the production energy consumption of fish feed. Although seaweed powder, guar gum and other ingredients can be added to the formula of fish feed to improve the physical quality of low-starch puffed floating feed at this stage, the addition of binders will increase the production cost of fish feed, and excessive addition of binders will also affect the digestion and absorption efficiency of puffed floating feed.

[0073] If the protein mash is subjected to a directed enzymatic hydrolysis reaction, the bacterial protein will form high molecular weight polysaccharide fragments, peptidoglycan fragments, nucleosides, peptides and incompletely degraded proteins. The interaction between these components can form a viscous system, which can effectively improve the physical quality of the extruded floating feed with low starch content. However, the adhesion of these viscous systems is closely related to the quality of peptide substances such as peptides and peptidoglycan fragments. Therefore, how to improve the utilization rate of ethanol Clostridium bacterial protein is a technical problem that needs to be solved urgently.

[0074] Figure 1 The schematic diagram of the process of treating a bacterial protein mash provided in an embodiment of the present application is exemplarily shown;

[0075] like Figure 1 As shown, the present application embodiment provides a method for treating bacterial protein mash, the method comprising:

[0076] S1. The bacterial protein mash is vacuum concentrated to obtain a concentrated protein mash;

[0077] S2. The concentrated protein mash is subjected to a cell wall breaking treatment to obtain a concentrated protein mash containing bacterial fragments;

[0078] S3. neutralizing the concentrated protein mash containing bacterial fragments using an alkaline solution to obtain a concentrated protein reaction solution;

[0079] S4. The concentrated protein reaction solution is subjected to enzymatic hydrolysis and enzyme inactivation treatment in sequence using a composite enzyme system to obtain a proteolysis reaction solution; wherein the raw materials of the composite enzyme system include lysozyme, alkaline protease, nuclease and flavor protease;

[0080] S5. Purify the proteolysis reaction solution to obtain a bacterial protein treatment solution.

[0081] It should be noted that the alkaline solution can change the concentrated protein mash from an acidic environment to an alkaline environment, and the bacterial protein in the concentrated protein mash will be fully dissolved in the concentrated protein mash in the alkaline environment; in addition, since the concentrated protein mash of ethanol Clostridium also contains bacterial metabolites such as acetic acid, lactic acid and phosphoric acid, after the neutralization reaction stage of the alkaline solution, acetic acid, lactic acid and phosphoric acid will form acetate, lactate and phosphate respectively. These salts can be used in puffed floating feed, and have the effects of nutritional supplementation, mineral supplementation and antibacterial, which can improve the ecological balance of intestinal microorganisms and promote intestinal digestion and absorption; in addition, the neutralization reaction can also convert the organic acid small molecules with a large unpleasant odor in the concentrated protein mash into corresponding organic salts, thereby reducing the unpleasant odor of the concentrated protein mash.

[0082] It should be noted that since the bacteria generally contain cell substances such as peptidoglycan and nucleic acid, these cell substances will be released into the concentrated protein mash containing bacterial fragments after the cell wall is broken. Under the catalytic action of the complex enzyme system including lysozyme, alkaline protease, nuclease and flavor protease, these peptidoglycans and nucleic acids will be converted into oligosaccharides, nucleosides and nucleosides respectively. These components can be used as additional additives in extruded floating feed to improve the nutritional composition of extruded floating feed.

[0083] It should be noted that the mass concentration of the bacteria in the bacterial protein mash can be 10g / L to 12g / L, and the mass concentration of the bacteria in the concentrated protein mash after vacuum concentration treatment can be 60g / L to 80g / L.

[0084] It should be noted that the pH value of the concentrated protein mash containing bacterial fragments is generally 4.5-4.8. Compared with the pH value of the concentrated protein mash before the cell wall breaking treatment, the pH value of the concentrated protein mash containing bacterial fragments is at a lower level. This may be caused by the cell wall breaking treatment releasing the acidic components in the bacterial cells into the liquid phase system of the concentrated protein mash.

[0085] It should be noted that the present application embodiment provides a method for treating bacterial protein mash, which effectively increases the content of peptide substances in bacterial protein mash through a series of fine steps. The specific process is as follows:

[0086] (1) First, the vacuum concentration technology is used to enrich the bacteria in the bacterial protein mash into a concentrated protein mash with a high bacterial concentration. This step improves the efficiency of subsequent processing by reducing the volume of the mash;

[0087] (2) Next, the concentrated protein mash with a high bacterial cell concentration is subjected to a cell wall breaking treatment. The cell wall breaking treatment can fully break up the bacterial cells, allowing the bacterial proteins and other nutrients in the cells to be released and evenly dispersed in the concentrated protein mash. This step ensures the effective extraction and dispersion of the nutrients;

[0088] (3) Subsequently, an alkaline solution is used to neutralize the uniformly distributed concentrated protein mash to place it in an alkaline environment. The alkaline environment helps promote the entry of bacterial protein into the liquid phase system, thereby obtaining a concentrated protein reaction solution with a high bacterial protein content. This step further improves the extraction efficiency of bacterial protein;

[0089] (4) Then, the concentrated protein reaction solution is subjected to an enzymatic hydrolysis reaction using a composite enzyme system including lysozyme, alkaline protease, nuclease and flavor protease. The composite enzyme system can work synergistically to convert most of the bacterial proteins into a variety of bioactive peptides. This step not only increases the content of peptide substances, but also increases the biological activity of the product;

[0090] (5) Finally, the enzymatic hydrolysis reaction is terminated by inactivating the enzyme, and the bioactive peptides and a small amount of bacterial protein generated by the enzymatic hydrolysis reaction are separated from the concentrated protein reaction liquid by purification, thereby obtaining a bacterial protein treatment liquid containing a large amount of peptide substances. This step ensures the purity and quality of the final product.

[0091] In summary, the embodiments of the present application provide a method for treating bacterial protein mash, which combines vacuum treatment, wall breaking treatment, neutralization reaction treatment, and enzymatic hydrolysis reaction. Through precise step control and optimized process parameters, the content of peptide substances in the bacterial protein mash is effectively improved, providing strong support for the high-value utilization of bacterial protein.

[0092] In some optional embodiments, the mass m1 of the lysozyme, the mass m2 of the alkaline protease, the mass m3 of the nuclease and the mass m4 of the flavor protease satisfy the relationship: m1:m2:m3:m4≥1:1:1:1.

[0093] In these embodiments, the mass m1 of lysozyme, the mass m2 of alkaline protease, the mass m3 of nuclease and the mass m4 of flavor protease can satisfy the relationship: m1:m2:m3:m4≥1:1:1:1, so that the complex enzyme system has sufficient lysozyme, alkaline protease, nuclease and flavor protease, and sufficient lysozyme can dissolve the cell wall of ethanolic Clostridium after wall-breaking treatment, and act on the β-1,4 glycosidic bond of peptidoglycan in the cell wall, so that the cell wall of ethanolic Clostridium disintegrates and the peptidoglycan forms small molecule oligosaccharides, and in addition, the ethanolic Clostridium with disintegrated cell wall will release a large amount of bacterial protein and nucleic acid components, and sufficient alkaline protein In the alkaline environment of the concentrated protein reaction solution, the enzyme will destroy the peptide bonds of the bacterial protein, so that the bacterial protein is decomposed into peptide substances, thereby increasing the concentration of peptide substances in the enzymatic hydrolysis reaction solution of the protease; in addition, a sufficient amount of nuclease can split the nucleic acid molecules into small fragments of nucleotides and nucleosides and other components, which can be quickly absorbed by the body and converted into corresponding nutrients; in addition, a sufficient amount of flavor protease can further convert bacterial proteins and some peptide substances into amino acids and peptides and other substances with specific flavors. These amino acids and peptides and other substances with specific flavors can improve the taste and flavor of subsequent puffed floating feeds and increase the food intake of carnivorous fish.

[0094] It should be noted that the lysozyme can use the lysozyme (20,000 U / g) produced by Nanning Dongheng Huadao Biotechnology Co., Ltd.; the alkaline protease can use the alkaline protease (200,000 U / g) produced by Nanning Dongheng Huadao Biotechnology Co., Ltd.; the nuclease can use the nuclease (11,000 U / g) produced by Suzhou Jinan Protein Technology Co., Ltd.; the flavor protease can use the flavor protease (30,000 U / g) produced by Nanning Dongheng Huadao Biotechnology Co., Ltd.

[0095] In some optional embodiments, the mass m2 of the alkaline protease, the mass m4 of the flavor protease and the weight m5 of the dry matter of the concentrated protein reaction solution satisfy the relationship: (m2+m4) / m5=(1-7):100.

[0096] In these embodiments, the mass m2 of the alkaline protease, the mass m4 of the flavor protease and the weight m5 of the dry matter of the concentrated protein reaction liquid can satisfy the relationship: (m2+m4) / m5=(1-7):100, so that the concentrated protein reaction liquid has sufficient alkaline protease and flavor protease. A sufficient amount of alkaline protease can destroy the peptide bonds of the bacterial protein in the alkaline environment of the concentrated protein reaction liquid, so that the bacterial protein is decomposed into peptide substances; in addition, a sufficient amount of flavor protease can further convert the bacterial protein and some peptide substances into amino acids and peptides and other substances with specific flavors. These amino acids and peptides and other substances with specific flavors can improve the taste and flavor of the subsequent puffed floating feed and increase the food intake of carnivorous fish.

[0097] The sum of the mass m2 of the alkaline protease and the mass m4 of the flavor protease can be 1, 2, 3, 4, 5, 6 or 7.

[0098] In some optional embodiments, the temperature of the enzymatic hydrolysis reaction is 30°C to 50°C, and the time of the enzymatic hydrolysis reaction is 3h to 7h; and / or

[0099] The temperature of the enzyme inactivation treatment is 70° C. to 100° C., and the time of the enzyme inactivation treatment is 5 min to 10 min.

[0100] In these embodiments, the temperature of the enzymatic reaction can be 30°C to 50°C, and the time of the enzymatic reaction can be 3h to 7h, so that the complex enzyme system can fully react with the concentrated protein mash containing bacterial fragments, promote the bacterial cell lysis of the concentrated protein mash containing bacterial fragments and produce a large amount of peptide substances, oligosaccharides, nucleotides and nucleosides, etc., so as to effectively increase the content of peptide substances in the bacterial protein mash. In addition, the temperature of the enzyme inactivation treatment can be 70°C to 100°C, and the time of the enzymatic reaction can be 5min to 10min, so that the complex enzyme system is fully inactivated to effectively terminate the process of the enzymatic reaction, thereby controlling the content of peptide substances in the bacterial protein mash.

[0101] The temperature of the enzymatic hydrolysis reaction can be 30°C, 35°C, 40°C, 45°C or 50°C.

[0102] The enzymatic reaction time can be 3h, 4h, 5h, 6h or 6h.

[0103] The temperature of the enzyme inactivation treatment may be 70°C, 75°C, 80°C, 85°C, 90°C, 95°C or 100°C.

[0104] The enzyme inactivation treatment time can be 5 min, 6 min, 7 min, 8 min, 9 min or 10 min.

[0105] In some optional embodiments, the pressure of the vacuum concentration is 0.07 MPa to 0.09 MPa, and the temperature of the vacuum concentration is 30° C. to 70° C.; and / or

[0106] The mass concentration of bacterial protein in the concentrated protein mash is 60 g / L to 80 g / L.

[0107] In these embodiments, the pressure of vacuum concentration can be 0.07MPa~0.09MPa, and the temperature of vacuum concentration can be 30℃~70℃. In addition, the mass concentration of bacterial protein in the concentrated protein mash can be 60g / L~80g / L. The mass concentration of bacteria in the bacterial protein mash is increased to a higher level under the pressure and temperature conditions, which can facilitate subsequent cell wall breaking treatment and enzymatic reaction treatment.

[0108] The pressure of the vacuum concentration may be 0.07 MPa, 0.075 MPa, 0.080 MPa, 0.085 MPa or 0.09 MPa.

[0109] The temperature of the vacuum concentration may be 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, 60°C, 65°C or 70°C.

[0110] The mass concentration of the bacterial protein in the concentrated protein mash can be 60g / L, 65g / L, 70g / L, 75g / L or 80g / L.

[0111] In some optional embodiments, the pressure of the cell wall breaking treatment is 40 MPa to 150 MPa; and / or

[0112] The end point acid-base of the neutralization reaction is 9-11.

[0113] In these embodiments, the pressure of the cell wall breaking treatment can be 40MPa~150Mpa, so that the bacteria in the concentrated protein mash are fully exposed, thereby facilitating the subsequent enzymatic hydrolysis reaction treatment; in addition, the end point acid-base of the neutralization reaction can be 9~11, which indicates that the concentrated protein reaction liquid is in a strong alkaline environment, which is convenient for the subsequent enzymatic hydrolysis reaction of the bacteria in the concentrated protein reaction liquid by the composite enzyme system.

[0114] The pressure of the wall breaking treatment can be 40MPa, 50MPa, 60MPa, 70MPa, 80MPa, 90MPa, 100MPa, 110MPa, 120MPa, 130MPa, 140MPa or 150MPa.

[0115] The end point acid-base of the neutralization reaction can be 9, 9.5, 10, 10.5 or 11.

[0116] Figure 2 The detailed process diagram of a method for treating bacterial protein mash provided in an embodiment of the present application is exemplarily shown;

[0117] In some optional embodiments, such as Figure 2 As shown, the proteolysis reaction liquid is purified to obtain a bacterial protein treatment liquid, comprising the steps of:

[0118] S501. Filtering the proteolysis reaction solution to obtain a protein filtrate;

[0119] S502. Desalting the protein filtrate to obtain a desalted protein solution;

[0120] S503. The desalted protein solution is subjected to the vacuum concentration using a composite gas and an adsorbent material to obtain a desalted protein concentrate;

[0121] S504. Sterilize the desalted protein concentrate to obtain a bacterial protein treated solution.

[0122] In these embodiments, the protein hydrolysis reaction liquid is filtered to remove large particles of impurities and ensure the purity of small molecules such as bacterial proteins, peptides, oligosaccharides, nucleotides and nucleosides; the protein filtrate is then desalted to remove metal ions such as sodium, magnesium, and iron from the protein filtrate, further reducing the odor of the bacterial protein, which helps to improve the taste and quality of the puffed floating feed; the desalted protein liquid is then vacuum concentrated using a composite gas and an adsorbent material, and the composite gas can remove the abnormal odor generated in the vacuum concentration stage, so that the dry matter weight content of the desalted protein liquid after vacuum concentration is above 50%; finally, the desalted protein concentrate is sterilized to kill miscellaneous bacteria and other microorganisms in the desalted protein concentrate and ensure the purity of the bacterial protein treatment liquid.

[0123] It should be noted that the filtration can be performed using a filter bag with a pore size of 500-1000 mesh; the temperature of the sterilization treatment is 121° C., and the time of the sterilization treatment is 15 minutes.

[0124] It should be noted that the desalination treatment can be carried out by electrodialysis. The specific process is: put the protein filtrate into the fresh water tank of the electrodialysis, then put the tap water into the concentrated water tank and put the sodium chloride brine into the extreme water tank, control the voltage of the electrodialysis to 200V, and carry out the electrodialysis according to the cycle period of 60min to 120min to obtain the desalted protein solution.

[0125] It should be noted that the adsorption material may be activated carbon.

[0126] In some optional embodiments, the composite gas includes carbon dioxide and / or nitrogen; when the composite gas includes carbon dioxide, the input flow rate of the carbon dioxide is 1% to 5% of the total flow rate of the composite gas; when the composite gas includes nitrogen, the input flow rate of the nitrogen is 1% to 5% of the total flow rate of the composite gas; and / or

[0127] The mass m6 of the adsorption material and the mass m7 of the desalted protein solution satisfy the relationship: m6:m7≥1:100.

[0128] In these embodiments, the composite gas may include carbon dioxide and / or nitrogen; when the composite gas includes carbon dioxide, the input flow rate of carbon dioxide may be 1% to 5% of the total flow rate of the composite gas; when the composite gas includes nitrogen, the input flow rate of nitrogen may be 1% to 5% of the total flow rate of the composite gas, so that there are sufficient carbon dioxide and nitrogen in the composite gas, thereby effectively removing the abnormal odor generated in the vacuum concentration stage. In addition, the mass m6 of the adsorption material and the mass m7 of the desalted protein solution may satisfy the relationship: m6:m7≥1:100, so that the desalted protein solution has sufficient adsorption material, and sufficient adsorption material can effectively enrich small molecules such as bacterial proteins, peptides, oligosaccharides, nucleotides and nucleosides, and prevent the composite gas from removing these small molecules, so that the dry matter weight content of the desalted protein solution after vacuum concentration is above 50%.

[0129] In the case where the composite gas includes carbon dioxide, the input flow rate of the carbon dioxide may be 1%, 2%, 3%, 4% or 5% of the total flow rate of the composite gas.

[0130] In the case where the composite gas includes nitrogen, the input flow rate of the nitrogen may be 1%, 2%, 3%, 4% or 5% of the total flow rate of the composite gas.

[0131] Figure 3 The following is a schematic diagram showing the logical structure of a bacterial protein mash processing system provided in an embodiment of the present application;

[0132] Figure 4 The actual structural diagram of a bacterial protein mash processing system provided in an embodiment of the present application is exemplarily shown;

[0133] Based on a general inventive concept, such as Figure 3 and Figure 4 As shown, the embodiment of the present application provides a system for processing bacterial protein mash, the system is adapted to the processing method, and the processing system includes:

[0134] The first vacuum concentration system 1 comprises a bacterial protein mash buffer tank 11, a first vacuum concentration device 12 and a concentrated protein mash buffer tank 13, wherein the discharge port of the bacterial protein mash buffer tank 11 is connected to the feed port of the first vacuum concentration device 12, and the discharge port of the first vacuum concentration device 12 is connected to the concentrated protein mash buffer tank 13;

[0135] A high-pressure homogenizer 2, wherein the discharge port of the concentrated protein mash buffer tank 13 is connected to the feed port of the high-pressure homogenizer 2 to achieve the wall breaking treatment of the concentrated protein mash;

[0136] The enzymolysis system 3 comprises a batching tank 31, an alkali solution feeding pipe 33 and an enzymolysis tank 32, wherein the feeding port of the batching tank 31 is connected to the discharging port of the high-pressure homogenizer 2, the discharging port of the batching tank 31 is connected to the feeding port of the enzymolysis tank 32, and the discharging port of the alkali solution feeding pipe 33 is connected to the liquid inlet of the enzymolysis tank 32, so that the concentrated protein mash undergoes a neutralization reaction and an enzymolysis reaction to obtain a protein hydrolysis reaction liquid;

[0137] The purification treatment section is connected to the discharge port of the enzymolysis tank 32 to purify the protein hydrolysis reaction liquid to obtain a bacterial protein treatment liquid.

[0138] The processing system is implemented based on the above processing method. The specific steps of the processing method can refer to the above embodiments. Since the processing system adopts part or all of the technical solutions of the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here.

[0139] In some optional embodiments, the purification treatment unit includes: a filter 4, an electrodialysis system 5, a second vacuum concentration system 6 and a sterilization device 7;

[0140] The feed port of the filter 4 is connected to the discharge port of the enzymolysis tank 32;

[0141] The electrodialysis system 5 includes an electrodialysis device 51 and a desalted liquid temporary storage tank 52. The feed port of the electrodialysis device 51 is connected to the discharge port of the filter 4 so that the protein hydrolysis reaction liquid is desalted to obtain a desalted protein liquid; the feed port of the desalted liquid temporary storage tank 52 is connected to the feed port of the electrodialysis device 51 to store the desalted protein liquid.

[0142] The second vacuum concentrating system 6 includes a second vacuum concentrating device 61, a gas conduit 62, an adsorption material feed pipe 63 and a desalted protein material tank 64. The feed port of the second vacuum concentrating device 61 is connected to the discharge port of the electrodialysis device 51, the gas conduit 62 is connected to the air inlet of the second vacuum concentrating device 61, the adsorption material feed pipe 63 is connected to the feed port of the second vacuum concentrating device 61, and the feed port of the desalted protein material tank 64 is connected to the discharge port of the second vacuum concentrating device 61; the discharge port of the desalted protein material tank 64 is connected to the sterilization device 7 to sterilize the desalted protein concentrate.

[0143] In these embodiments, the filter 4 is first used to filter and remove impurities from the protein hydrolysis reaction liquid stored in the enzymolysis tank 32, so as to remove large particle impurities in the protein hydrolysis reaction liquid; then the electrodialysis device 51 is used to further remove metal ions such as sodium, magnesium, and iron from the protein filtrate, and then the desalted protein liquid is stored in the desalted liquid temporary storage tank 52; then a second vacuum concentration system 6 including a second vacuum concentrator 61, a gas conduit 62, an adsorption material feed pipe 63 and a desalted protein material tank 64 is used, and the composite gas is introduced into the second vacuum concentrator 61 by using the gas conduit 62, and then the adsorption material feed pipe 63 is used to introduce the adsorption material into the second vacuum concentrator 61, so that the dry matter weight content of the desalted protein liquid after vacuum concentration is above 50%; finally, the desalted protein concentrate obtained by the second vacuum concentrator 61 is stored in the desalted protein material tank 64 to facilitate the subsequent treatment by the sterilization device 7, so as to finally obtain a pure bacterial protein treated liquid.

[0144] It should be noted that the filter 4 is provided with a microfiltration membrane, which can effectively remove large particle impurities in the proteolysis reaction solution and ensure the purity of small molecules such as bacterial proteins, peptides, oligosaccharides, nucleotides and nucleosides.

[0145] Based on a general inventive concept, an embodiment of the present application provides an expanded floating feed, which includes a bacterial protein processing liquid obtained by the processing method.

[0146] The puffed floating feed is realized based on the above-mentioned processing method. The specific steps of the processing method can refer to the above-mentioned embodiment. Since the puffed floating feed adopts part or all of the technical solutions of the above-mentioned embodiment, it has at least all the beneficial effects brought by the technical solutions of the above-mentioned embodiment, which will not be described one by one here.

[0147] In some optional embodiments, the raw materials of the puffed floating feed include, by weight, 8 to 28 parts of the bacterial protein processing liquid, 20 to 30 parts of fish meal, 53 to 56 parts of solid additives, 8.5 to 9.0 parts of compound oil, 1.4 to 2.2 parts of auxiliary materials, and ≥ 1 part of premix.

[0148] In these embodiments, the weight proportion of the bacterial protein treatment liquid can be 8 to 28 parts, and the nutritional components of the puffed floating feed can be improved by the bacterial protein and small molecules such as peptides, oligosaccharides, nucleotides and nucleosides in the bacterial protein treatment liquid. In addition, these small molecules have high adhesion and can replace the adhesion function of starch in traditional puffed floating feed to achieve autonomous adhesion of puffed floating feed; in addition, the weight proportion of fish meal can be 20 to 30 parts, which can provide sufficient high-quality protein for the animal body to promote the growth and development of the animal body and enhance the immunity of the animal body. In addition, fish meal can also improve the quality of puffed floating feed and increase the food intake of the animal body; in addition, the weight proportion of solid additives is 53 to 56 parts, which can provide more comprehensive nutrition for the animal body and The invention can promote the digestion of the animal body to improve the utilization rate of the puffed floating feed; in addition, the weight portion of the compound oil can be 8.5 to 9.0 parts, which can improve the quality of the puffed floating feed, increase the growth rate of the animal body and enhance the immunity of the animal body, thereby improving the utilization rate of the puffed floating feed; in addition, the weight portion of the auxiliary material can be 1.4 to 2.2 parts, which can provide the animal body with necessary minerals and improve the palatability of the puffed floating feed to promote the growth of the animal body and enhance the immunity of the animal body; in addition, the weight portion of the premix is ​​≥1 part, which can improve the quality of the puffed floating feed through the premix, enhance the health of the animal body, and improve the utilization rate of the puffed floating feed. In addition, the premix can also improve the floating property of the puffed floating feed, which is convenient for feeding and management.

[0149] The weight proportions of the bacterial protein treatment liquid can be 8 parts, 9 parts, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 20 parts, 25 parts or 28 parts.

[0150] The weight proportions of the fish meal can be 20 parts, 21 parts, 22 parts, 23 parts, 24 parts, 25 parts, 26 parts, 27 parts, 28 parts, 29 parts or 30 parts.

[0151] The weight proportion of the solid additive can be 53 parts, 54 parts, 55 parts or 56 parts.

[0152] The weight proportion of the composite oil may be 8.5 parts, 8.6 parts, 8.7 parts, 8.8 parts, 8.9 parts or 9.0 parts.

[0153] The weight proportions of the auxiliary material can be 1.4 parts, 1.5 parts, 1.6 parts, 1.7 parts, 1.8 parts, 1.9 parts, 2.0 parts, 2.1 parts or 2.2 parts.

[0154] It should be noted that the role of this fish meal is mainly reflected in the following aspects:

[0155] (1) As an important component of extruded floating feed, fish meal is rich in high-quality protein that can meet the nutritional needs of animals during their growth. These proteins contain essential amino acids such as lysine, tryptophan, methionine and cystine, which are in appropriate proportions and are easily digested and absorbed by animals, thus effectively promoting the growth and development of animals.

[0156] (2) In addition, minerals in fish meal, such as calcium, iodine, and selenium, also play an important role in the bone development and physiological functions of animals, and can further enhance the physical fitness and health level of animals.

[0157] (3) In terms of immunity, the high-quality protein and various nutrients in fish meal can effectively promote the generation and repair of animal immune cells and enhance the function of the immune system. At the same time, the long-chain polyunsaturated fatty acids in fish meal, such as ω-3 PUFA, have anti-inflammatory, antioxidant and immune-promoting effects, which can significantly improve the immune ability and health level of animals24.

[0158] (4) Finally, fish meal can also improve the overall quality of feed. Its unique smell and taste can stimulate the animal's sense of smell and taste, increase appetite, and improve the palatability of feed. At the same time, the high-quality protein and rich nutrients in fish meal can improve the nutritional value of feed, making the feed more balanced and comprehensive.

[0159] In summary, the fish meal in this extruded floating feed plays an important role in providing nutrition, promoting growth, enhancing immunity and improving feed quality.

[0160] It should be noted that, by weight, the solid additive may include: 20 parts of cottonseed protein concentrate, 8 parts of soybean protein concentrate, 4 parts of soybean meal, 4 parts of mealworms, 6 parts of gluten, 4 parts of cassava flour, 4 parts of flour, and 3.8 to 5.1 parts of microcrystalline cellulose. These materials have the following effects:

[0161] (1) Provide comprehensive nutrition: Cottonseed protein concentrate and soybean protein concentrate are high-quality plant protein sources, rich in amino acids, and can meet the protein needs of animals during growth. Soybean meal is also rich in crude protein and amino acids, and is an indispensable high-quality plant protein source in breeding production. In addition, mealworms, as an animal protein source, provide additional protein and essential amino acids, which helps to improve the nutritional value of puffed floating feed.

[0162] (2) Promote digestion and absorption: The addition of carbohydrate raw materials such as gluten, cassava flour and flour helps to improve the taste and texture of the feed, making it easier for the animal body to accept and digest the puffed floating feed. The addition of microcrystalline cellulose can increase the fiber content of the puffed floating feed to promote intestinal peristalsis and help the digestive health of the animal body.

[0163] (3) Improve feed utilization: Extruded floating feed can be suspended on the water surface for a long time, which is convenient for animals to eat and reduces the waste of extruded floating feed. In addition, the reasonable combination of various raw materials in the extruded floating feed makes the nutrition more balanced and improves the conversion rate and utilization rate of the extruded floating feed.

[0164] (4) Enhance animal health: High-quality protein sources such as cottonseed protein concentrate, soybean protein concentrate and soybean meal not only provide necessary nutrition, but also help enhance the immunity and resistance of animals. In addition, animal protein sources such as mealworms are rich in a variety of nutrients, such as vitamins and minerals, which have a positive effect on the growth, development and health maintenance of animals.

[0165] In summary, the formulation of the above solid additives used in extruded floating feed can fully meet the nutritional needs of animals, promote digestion and absorption, improve feed utilization, and help enhance the health level of animals.

[0166] It should be noted that, by weight, the composite oil may include: 2 parts of phospholipid oil, 3.5 parts of fish oil, and 3.0 to 3.5 parts of soybean oil. These materials have the following effects:

[0167] (1) Improve feed quality: Lecithin oil has good emulsification and dispersibility, which can improve the physical properties of puffed floating feed, make the particles of puffed floating feed more uniform and delicate, improve the stability and palatability of puffed floating feed, and help animals to better ingest, digest and absorb.

[0168] (2) Improve animal growth performance: Fish oil is rich in unsaturated fatty acids, especially n-3 fatty acids, which have a positive effect on the growth and development of animals. In addition, the addition of fish oil can significantly increase the weight gain rate and feed conversion rate of animals, shorten the breeding cycle, and reduce breeding costs. In addition, soybean oil is also rich in essential fatty acids, which helps the cell growth and tissue development of animals and accelerates growth.

[0169] (3) Enhance immunity: The phospholipids in lecithin oil play an important regulatory role in the immune system of animals. They can enhance the resistance and disease resistance of animals and prevent the occurrence and spread of diseases. In addition, n-3 fatty acids in fish oil can also help improve the immunity of animals and reduce the production of inflammatory mediators in immune cells, thereby enhancing the health level of animals.

[0170] (4) Improve feed utilization: The addition of phospholipid oil, fish oil and soybean oil can promote animals' digestion and absorption of fat, reduce feed waste and improve feed utilization.

[0171] In summary, adding compound oils such as phospholipid oil, fish oil and soybean oil to extruded floating feed can significantly improve the overall quality of extruded floating feed, promote the growth and development of animals, enhance immunity, and improve the utilization rate of extruded floating feed, thereby bringing higher economic benefits to the breeding industry.

[0172] It should be noted that, by weight, the auxiliary materials may include: 1.0 to 1.8 parts of monocalcium phosphate, 0.4 parts of choline chloride. These materials have the following effects:

[0173] (1) Provide essential minerals: As an additive to puffed floating feed, calcium dihydrogen phosphate can provide the animal body with essential phosphorus and calcium minerals. These minerals are essential for the animal's bone development, physiological function maintenance and overall health.

[0174] (2) Improve the palatability of puffed floating feed: The addition of calcium dihydrogen phosphate can also improve the palatability of puffed floating feed, making it easier for animals to accept and digest it, thereby increasing the utilization rate of puffed floating feed and the food intake of animals.

[0175] (3) Promote animal growth: Choline chloride, as a growth promoter, can stimulate the metabolism of animals and accelerate growth. Adding choline chloride to extruded floating feed can significantly improve the growth performance and weight gain of animals, bringing more benefits to the breeding industry.

[0176] (4) Enhance immunity: Choline chloride not only promotes the growth of animal bodies, but also helps to improve the immunity of animal bodies. It can enhance the disease resistance and health level of animal bodies, reduce the incidence of diseases, and make the breeding process more stable and reliable.

[0177] In summary, adding calcium dihydrogen phosphate and choline chloride as auxiliary materials to extruded floating feed can comprehensively improve the nutritional value of extruded floating feed and the growth performance of animals, bringing positive effects to the breeding industry.

[0178] Figure 5 A schematic flow chart of a method for preparing puffed floating feed provided in an embodiment of the present application is exemplarily shown.

[0179] Based on a general inventive concept, such as Figure 5 As shown, an embodiment of the present application provides a method for preparing the puffed floating feed, the method comprising:

[0180] S1. The fish meal, solid additives, compound oil, auxiliary materials and premix are mixed to obtain a solid matrix;

[0181] S2. The bacterial protein treatment liquid obtained by the treatment method is subjected to a first conditioning using a solvent to obtain a liquid matrix;

[0182] S3. mixing the liquid matrix and the solid matrix to obtain a mixed raw material;

[0183] S4. The mixed raw material is subjected to a second conditioning to obtain a feed raw material;

[0184] S5. The feed raw materials are sequentially extruded, dried and sprayed with oil to obtain expanded floating feed particles.

[0185] This method is a method for preparing the above-mentioned puffed floating feed. The specific composition of the puffed floating feed can refer to the above-mentioned embodiment. Since this method adopts part or all of the technical solutions of the above-mentioned embodiment, it at least has all the beneficial effects brought by the technical solutions of the above-mentioned embodiment, which will not be described one by one here.

[0186] It should be noted that this method is different from the traditional preparation of puffed floating feed. Its principle is to directly use the bacterial protein treated liquid as a liquid matrix and mix it with other dry material components of the puffed floating feed. The mixing degree of the liquid matrix and the solid matrix is ​​improved through the particle gaps of the dry material and its own adsorption, which facilitates the subsequent second conditioning and the forming of the puffed floating feed particles.

[0187] It should be noted that the solvent can be deionized water.

[0188] It should be noted that the first conditioning can be performed in a conditioner.

[0189] It should be noted that the solid matrix can be crushed and sieved before use to obtain small particles of solid matrix below 80 mesh, so that the solid matrix has a good specific surface area and the liquid matrix can be fully mixed with the solid matrix.

[0190] In some optional embodiments, the mass m8 of the bacterial protein treatment solution and the mass m9 of the solvent satisfy the relationship: m8:m9=(8-28):(17.25-7.36); and / or

[0191] The mass of the solvent of the liquid phase matrix is ​​less than or equal to 70% of the mass of the liquid phase matrix.

[0192] In these embodiments, the mass m8 of the bacterial protein treated liquid and the mass m9 of the solvent can satisfy the relationship: m8:m9=(8~28):(17.25~7.36). Based on the fact that the bacterial protein treated liquid contains a large amount of water-soluble components of small molecular substances such as peptides, oligosaccharides, nucleotides and nucleosides, these water-soluble components can be used as plasticizers to increase the adhesion of the expanded floating feed. Therefore, as the usage of the bacterial protein treated liquid gradually increases, the amount of solvent added is controlled to gradually decrease, and the content of the solvent used for conditioning can be reduced to 25%, so that the adhesion of the bacterial protein treated liquid reaches the optimal level; in addition, the bacterial protein treated liquid has a high content of peptides and bacterial proteins, which makes it have better foaming properties, which is conducive to the subsequent extrusion puffing.

[0193] The mass m8 of the bacterial protein processing liquid can be 8, 9, 10, 11, 12, 13, 14, 15, 20, 25 or 28.

[0194] The mass m9 of the solvent can take a value of 17.25, 17.00, 16.75, 16.50, 16.25, 16.00, 15.00, 14.00, 13.00, 12.00, 11.00, 10.00, 9.00, 8.00, 7.75, 7.50 or 7.36.

[0195] In some optional embodiments, the temperature of the second conditioning is 90° C. to 95° C., and the time of the second conditioning is 8 min to 12 min; and / or

[0196] The extrusion temperature is 120°C to 150°C, and the extrusion pressure is 3MPa to 5MPa; and / or

[0197] The drying temperature is 95° C. to 103° C., and the drying time is 1 h to 2 h.

[0198] In these embodiments, the temperature of the second conditioning can be 90°C to 95°C, and the time of the second conditioning can be 8min to 12min. Under this temperature condition, the solvent of the second conditioning will form steam, which can promote the liquid matrix to fully foam and allow the bacterial protein and small molecules to fully enter the solid matrix, thereby obtaining an expanded floating feed with high adhesion and rich nutrients; in addition, the temperature of extrusion puffing is 120°C to 150°C, and the pressure of extrusion puffing can be 3MPa to 5MPa, so that the feed raw materials are initially formed into particles, which is convenient for subsequent drying and spraying of oil; in addition, the drying temperature can be 95°C to 103°C, and the drying time can be 1h to 2h, so that the moisture of the granular feed raw materials is effectively removed to obtain dry expanded floating feed particles.

[0199] The temperature of the second conditioning may be 90°C, 91°C, 92°C, 93°C, 94°C or 95°C.

[0200] The second conditioning time can be 8 min, 9 min, 10 min, 11 min or 12 min.

[0201] The extrusion puffing temperature is 90°C, 91°C, 92°C, 93°C, 94°C, 95°C, 96°C, 97°C, 98°C, 99°C or 100°C.

[0202] The extrusion pressure may be 3 MPa, 3.5 MPa, 4 MPa, 4.5 MPa or 5 MPa.

[0203] The drying temperature may be 95°C, 96°C, 97°C, 98°C, 99°C, 100°C, 102°C or 103°C.

[0204] The drying time can be 1 h, 1.1 h, 1.2 h, 1.3 h, 1.4 h, 1.5 h, 1.6 h, 1.7 h, 1.8 h, 1.9 h or 2.0 h.

[0205] The present application is further described below in conjunction with specific examples. The experimental methods in the following examples where specific conditions are not specified are usually measured in accordance with national standards / industry standards; if there are no corresponding national standards / industry standards, they are measured in accordance with common international standards, conventional conditions or conditions recommended by the manufacturer.

[0206] Example 1

[0207] like Figure 2 As shown, a method for processing bacterial protein mash comprises:

[0208] S1. The 500L bacterial protein mash with a bacterial mass concentration of 12g / L was vacuum concentrated to obtain a 100L concentrated protein mash with a bacterial mass concentration of 60g / L;

[0209] S2. The concentrated protein mash is subjected to cell wall breaking treatment and cycled twice to obtain a concentrated protein mash containing bacterial fragments;

[0210] S3. The concentrated protein mash containing bacterial fragments having a pH of 4.5 was neutralized using an alkaline solution to obtain a concentrated protein reaction solution;

[0211] S4. The concentrated protein reaction solution was subjected to enzymatic hydrolysis and enzyme inactivation treatment in sequence using 60 g of a complex enzyme system to obtain a proteolysis reaction solution; wherein the raw materials of the complex enzyme system include lysozyme, alkaline protease, nuclease and flavor protease;

[0212] S501. The proteolysis reaction solution was filtered using a 500-mesh filter bag to obtain a protein filtrate;

[0213] S502. The protein filtrate having an initial conductivity of 10000 μS / cm was subjected to electrodialysis desalination treatment, the electrodialysis voltage was 200 V, the electrodialysis cycle was 60 min, and a desalted protein solution having a conductivity of 5000 μS / cm was obtained;

[0214] S503. The desalted protein solution was vacuum concentrated using a composite gas and 1 kg of adsorption material to obtain a desalted protein concentrate;

[0215] S504. Sterilize the desalted protein concentrate at 121°C for 15 minutes to obtain a bacterial protein treated solution.

[0216] The mass m1 of lysozyme, the mass m2 of alkaline protease, the mass m3 of nuclease and the mass m4 of flavor protease satisfy the relationship: m1:m2:m3:m4=1:1:1:1.

[0217] The mass m2 of alkaline protease, the mass m4 of flavor protease and the weight m5 of dry matter of concentrated protein reaction solution satisfy the relationship: (m2+m4) / m5=1:100.

[0218] The temperature of the enzymatic hydrolysis reaction was 30°C, and the time of the enzymatic hydrolysis reaction was 3 h;

[0219] The temperature for enzyme inactivation treatment was 80°C, and the time for enzymatic hydrolysis was 10 min.

[0220] The pressure of vacuum concentration is 0.08MPa, and the temperature of vacuum concentration is 40°C;

[0221] The mass concentration of bacterial protein in the concentrated protein mash is 60g / L.

[0222] The pressure of the wall breaking treatment is 40MPa;

[0223] The end point acid-base of the neutralization reaction is 9.

[0224] The composite gas includes carbon dioxide and nitrogen; when the composite gas includes carbon dioxide, the input flow rate of carbon dioxide is 1.5% of the total flow rate of the composite gas; when the composite gas includes nitrogen, the input flow rate of nitrogen is 1.5% of the total flow rate of the composite gas;

[0225] The mass m6 of the adsorption material and the mass m7 of the desalted protein solution satisfy the relationship: m6:m7=1:100.

[0226] like Figure 3 and Figure 4As shown, the embodiment of the present application provides a system for processing bacterial protein mash, and the system is adapted to the processing method, including:

[0227] The first vacuum concentration system 1 comprises a bacterial protein mash buffer tank 11, a first vacuum concentration device 12 and a concentrated protein mash buffer tank 13, wherein the discharge port of the bacterial protein mash buffer tank 11 is connected to the feed port of the first vacuum concentration device 12, and the discharge port of the first vacuum concentration device 12 is connected to the concentrated protein mash buffer tank 13;

[0228] The discharge port of the high-pressure homogenizer 2 and the concentrated protein mash buffer tank 13 are connected to the feed port of the high-pressure homogenizer 2 to achieve the wall breaking treatment of the concentrated protein mash;

[0229] The enzymolysis system 3 includes a batching tank 31, an alkali solution feeding pipe 33 and an enzymolysis tank 32, wherein the feeding port of the batching tank 31 is connected to the discharging port of the high-pressure homogenizer 2, the discharging port of the batching tank 31 is connected to the feeding port of the enzymolysis tank 32, and the discharging port of the alkali solution feeding pipe 33 is connected to the liquid inlet of the enzymolysis tank 32, so that the concentrated protein mash undergoes a neutralization reaction and an enzymolysis reaction to obtain a protein hydrolysis reaction liquid;

[0230] The purification treatment section is connected to the discharge port of the enzymolysis tank 32 to purify the protein hydrolysis reaction liquid to obtain the bacterial protein treatment liquid.

[0231] The purification treatment section includes: a filter 4, an electrodialysis system 5, a second vacuum concentration system 6 and a sterilization device 7;

[0232] The feed port of the filter 4 is connected to the discharge port of the enzymolysis tank 32;

[0233] The electrodialysis system 5 includes an electrodialysis device 51 and a desalted liquid temporary storage tank 52. The feed port of the electrodialysis device 51 is connected to the discharge port of the filter 4 so that the protein hydrolysis reaction liquid is desalted to obtain a desalted protein liquid; the feed port of the desalted liquid temporary storage tank 52 is connected to the feed port of the electrodialysis device 51 to store the desalted protein liquid;

[0234] The second vacuum concentrating system 6 includes a second vacuum concentrating device 61, a gas conduit 62, an adsorption material feed pipe 63 and a desalted protein material tank 64. The feed port of the second vacuum concentrating device 61 is connected to the discharge port of the electrodialysis device 51, the gas conduit 62 is connected to the air inlet of the second vacuum concentrating device 61, the adsorption material feed pipe 63 is connected to the feed port of the second vacuum concentrating device 61, and the feed port of the desalted protein material tank 64 is connected to the discharge port of the second vacuum concentrating device 61; the discharge port of the desalted protein material tank 64 is connected to the sterilization device 7 to sterilize the desalted protein concentrate.

[0235] Example 2

[0236] Based on the contents disclosed in Example 1, the following modifications are further made:

[0237] The mass m2 of alkaline protease, the mass m4 of flavor protease and the weight m5 of dry matter of concentrated protein reaction solution satisfy the relationship: (m2+m4) / m5=5:100.

[0238] The temperature of the enzymatic hydrolysis reaction was 40°C, and the time of the enzymatic hydrolysis reaction was 7 h;

[0239] The temperature for the enzyme inactivation treatment was 70°C and the time for the enzyme inactivation treatment was 10 min.

[0240] The pressure of vacuum concentration is 0.09MPa, and the temperature of vacuum concentration is 30°C;

[0241] The mass concentration of bacterial protein in the concentrated protein mash is 70g / L.

[0242] The pressure of the wall breaking treatment is 100Mpa;

[0243] The end point acid-base of the neutralization reaction is 10.

[0244] Example 3

[0245] Based on the contents disclosed in Example 1, the following modifications are further made:

[0246] The mass m2 of alkaline protease, the mass m4 of flavor protease and the weight m5 of dry matter of concentrated protein reaction solution satisfy the relationship: (m2+m4) / m5=7:100.

[0247] The temperature of the enzymatic hydrolysis reaction was 50°C, and the time of the enzymatic hydrolysis reaction was 4 h;

[0248] The temperature of the enzyme inactivation treatment was 100°C and the time of the enzyme inactivation treatment was 5 minutes.

[0249] The pressure of vacuum concentration is 0.07MPa, and the temperature of vacuum concentration is 70°C;

[0250] The mass concentration of bacterial protein in the concentrated protein mash is 78g / L.

[0251] The pressure of the wall breaking treatment is 150Mpa;

[0252] The end point acid-base of the neutralization reaction is 11.

[0253] Example 4

[0254] Based on the processing method disclosed in Example 1, the following modifications are further made:

[0255] The invention discloses an expanded floating feed, which comprises a bacterial protein processing liquid obtained by a processing method.

[0256] Calculated by weight, the raw materials of the puffed floating feed include 16 parts of bacterial protein processing liquid, 26 parts of fish meal, 54.9 parts of solid additives, 8.7 parts of compound oil, 1.4 parts of auxiliary materials, and 1 part of premix.

[0257] The solid additives include: 20 parts of cottonseed protein concentrate, 8 parts of soybean protein concentrate, 4 parts of soybean meal, 4 parts of mealworms, 6 parts of gluten, 4 parts of cassava flour, 4 parts of flour, and 4.9 parts of microcrystalline cellulose.

[0258] The compound oil includes: lecithin oil: 2 parts, fish oil: 3.5 parts, soybean oil: 3.2 parts.

[0259] Auxiliary materials include: monocalcium phosphate: 1.0 part, choline chloride: 0.4 part.

[0260] like Figure 3 As shown, a method for preparing expanded floating feed comprises:

[0261] S1. The fish meal, solid additives, compound oil, auxiliary materials and premix are mixed to obtain a solid matrix;

[0262] S2. The bacterial protein treatment liquid obtained by the treatment method is subjected to a first conditioning using a solvent to obtain a liquid matrix;

[0263] S3. mixing the liquid matrix and the solid matrix to obtain a mixed raw material;

[0264] S4. The mixed raw material is subjected to a second conditioning to obtain a feed raw material;

[0265] S5. The feed raw materials are sequentially extruded, dried and sprayed with oil to obtain expanded floating feed particles.

[0266] The mass m8 of the bacterial protein treatment solution and the mass m9 of the solvent satisfy the relationship: m8:m9=16:13.29;

[0267] The mass of the solvent of the liquid phase matrix is ​​less than or equal to 70% of the mass of the liquid phase matrix.

[0268] The temperature of the second tempering was 95° C., and the time of the second tempering was 10 min.

[0269] The extrusion temperature is 120°C and the extrusion pressure is 5MPa;

[0270] The drying temperature is 100°C and the drying time is 1.5h.

[0271] Example 5

[0272] Based on the contents disclosed in Example 4, the following modifications are further made:

[0273] Calculated by weight, the raw materials of the puffed floating feed include 20 parts of bacterial protein processing liquid, 24 parts of fish meal, 54 parts of solid additives, 8.8 parts of compound oil, 2.2 parts of auxiliary materials, and 1 part of premix.

[0274] The solid additives include: 20 parts of cottonseed protein concentrate, 8 parts of soybean protein concentrate, 4 parts of soybean meal, 4 parts of mealworms, 6 parts of gluten, 4 parts of cassava flour, 4 parts of flour, and 4.0 parts of microcrystalline cellulose.

[0275] The compound oil comprises: lecithin oil: 2 parts, fish oil: 3.5 parts, soybean oil: 3.3 parts.

[0276] Auxiliary materials include: monocalcium phosphate: 1.8 parts, choline chloride: 0.4 parts.

[0277] Example 6

[0278] Based on the contents disclosed in Example 4, the following modifications are further made:

[0279] Calculated by weight, the raw materials of the puffed floating feed include 24 parts of bacterial protein processing liquid, 22 parts of fish meal, 53.9 parts of solid additives, 8.9 parts of compound oil, 2.2 parts of auxiliary materials, and 1 part of premix.

[0280] The solid additives include: cottonseed protein concentrate: 20 parts, soybean protein concentrate: 8 parts, soybean meal: 4 parts, mealworms: 4 parts, gluten: 6 parts, cassava flour: 4 parts, flour: 4 parts, and microcrystalline cellulose: 3.9 parts.

[0281] The compound oil includes: lecithin oil: 2 parts, fish oil: 3.5 parts, soybean oil: 3.4 parts.

[0282] Auxiliary materials include: monocalcium phosphate: 1.8 parts, choline chloride: 0.4 parts.

[0283] Example 7

[0284] Based on the contents disclosed in Example 4, the following modifications are further made:

[0285] The mass m8 of the bacterial protein treatment solution and the mass m9 of the solvent satisfy the relationship: m8:m9=16:15;

[0286] The mass of the solvent of the liquid phase matrix is ​​less than or equal to 70% of the mass of the liquid phase matrix.

[0287] The temperature of the second quenching and tempering is 90°C, and the time of the second quenching and tempering is 12 minutes;

[0288] The extrusion temperature is 130°C and the extrusion pressure is 5MPa;

[0289] The drying temperature is 95°C and the drying time is 2h.

[0290] Example 8

[0291] Based on the contents disclosed in Example 4, the following modifications are further made:

[0292] The mass m8 of the bacterial protein treatment solution and the mass m9 of the solvent satisfy the relationship: m8:m9=16:17;

[0293] The mass of the solvent of the liquid phase matrix is ​​less than or equal to 70% of the mass of the liquid phase matrix.

[0294] The temperature of the second quenching and tempering is 93°C, and the time of the second quenching and tempering is 8 minutes;

[0295] The extrusion temperature is 150°C and the extrusion pressure is 5MPa;

[0296] The drying temperature is 103°C and the drying time is 1h.

[0297] Comparative Example 1

[0298] Based on the contents disclosed in Example 1, the following modifications are further made:

[0299] Without using enzymatic hydrolysis, the concentrated protein reaction liquid is directly purified to obtain a bacterial protein treatment liquid.

[0300] Comparative Example 2

[0301] Based on the contents disclosed in Example 1, the following modifications are further made:

[0302] The temperature of the enzymatic hydrolysis reaction is 25° C., and the time of the enzymatic hydrolysis reaction is 8 h.

[0303] Comparative Example 3

[0304] Based on the contents disclosed in Example 1, the following modifications are further made:

[0305] The temperature of the enzymatic hydrolysis reaction is 60° C., and the time of the enzymatic hydrolysis reaction is 2 h.

[0306] Comparative Example 4

[0307] Based on the contents disclosed in Example 4, the following modifications are further made:

[0308] Without adding bacterial protein treatment solution, fish meal is used directly: 34 parts.

[0309] Comparative Example 5

[0310] Based on the contents disclosed in Example 4, the following modifications are further made:

[0311] Calculated by weight, the raw materials of the puffed floating feed include 8 parts of bacterial protein treated liquid, 30 parts of fish meal, 55.1 parts of solid additives, 8.5 parts of compound oil, 1.4 parts of auxiliary materials and 1 part of premix.

[0312] The solid additives include: cottonseed protein concentrate: 20 parts, soybean protein concentrate: 8 parts, soybean meal: 4 parts, mealworms: 4 parts, gluten: 6 parts, cassava flour: 4 parts, flour: 4 parts, and microcrystalline cellulose: 5.1 parts.

[0313] The compound oil comprises: lecithin oil: 2 parts, fish oil: 3.5 parts, soybean oil: 3.0 parts.

[0314] Auxiliary materials include: monocalcium phosphate: 1.0 part, choline chloride: 0.4 part.

[0315] Comparative Example 6

[0316] Based on the contents disclosed in Example 4, the following modifications are further made:

[0317] Calculated by weight, the raw materials of the expanded floating feed include 12 parts of bacterial protein treatment liquid, 28 parts of fish meal, 55 parts of solid additives, 8.6 parts of compound oil, 1.4 parts of auxiliary materials, and 1 part of premix.

[0318] The solid additives include: 20 parts of cottonseed protein concentrate, 8 parts of soybean protein concentrate, 4 parts of soybean meal, 4 parts of mealworms, 6 parts of gluten, 4 parts of cassava flour, 4 parts of flour, and 5.0 parts of microcrystalline cellulose.

[0319] The compound oil comprises: lecithin oil: 2 parts, fish oil: 3.5 parts, soybean oil: 3.1 parts.

[0320] Auxiliary materials include: monocalcium phosphate: 1.0 part, choline chloride: 0.4 part.

[0321] Related experiments and effect data:

[0322] 1. Experiments related to bacterial protein treatment solution:

[0323] 1. The bacterial protein treatment solution of Example 1 was statistically analyzed and tested according to the following test items:

[0324] (1) Detection of crude protein, crude fat, moisture, ash and amino acid composition: All chemical analysis methods were based on the methods provided by AOAC (2006). Moisture content was detected in an oven at 105°C; crude protein was detected using the Kjeldahl method, and crude protein content was calculated by multiplying nitrogen content by 6.25; crude fat was determined by acid hydrolysis and then extracted using the Soxhlet extraction method; ash content was determined by placing the sample in a muffle furnace and burning it at 550°C for 16 hours; amino acid content was determined using an amino acid analyzer.

[0325] (2) Detection of peptide content: Weigh 0.3 g of bacterial protein treatment solution into a 10 mL volumetric flask, use the mobile phase (volume of acetonitrile: volume of water: volume of trichloroacetic acid = 45:55:0.1) to make up the volume of the bacterial protein treatment solution to the scale of the volumetric flask, and then ultrasonically oscillate for 10 min to fully dissolve and mix the samples in the volumetric flask to obtain a mixed solution; filter the mixed solution using a 0.22 μm nylon filter membrane to obtain a filtrate; take the filtrate, and determine the weight content of peptide substances and the weight content of peptide segments with a relative molecular mass ≤5000 Da in the bacterial protein treatment solution according to the detection method described in "GB / T22729-2008 Marine Fish Oligopeptide Powder".

[0326] (3) Molecular weight distribution: Weigh 0.3 g of the bacterial protein treatment solution into a 10 mL volumetric flask, and use the mobile phase (volume of acetonitrile: volume of water: volume of trichloroacetic acid = 40:60:0.05) to make up the volume of the bacterial protein treatment solution to the scale of the volumetric flask, and then ultrasonically oscillate for 10 min to fully dissolve and mix the samples in the volumetric flask to obtain a mixed solution; filter the mixed solution using a 0.22 μm nylon filter membrane to obtain a filtrate; take the filtrate and perform detection and analysis based on high performance size exclusion chromatography according to the detection method described in "GB 31645-2008 Collagen Peptide". Detection and analysis conditions: equipped with a UV detector and a chromatography workstation with GPC data processing software; chromatographic column: TSKgel G2000SWXL, size 300mm×7.8mm; mobile phase: acetonitrile, water and trichloroacetic acid, the volume ratio of the three is 40:60:0.05; detection wavelength: 220nm; flow rate: 0.5mL / min; column temperature: 30℃; injection volume: 10μm; standard substances used for relative molecular mass calibration curve: cytochrome (MW12384), aprotinin (MW6512), bacillus enzyme (MW451), tyrosine-tyrosine-arginine (MW451), tyrosine-tyrosine-tyrosine (MW189). Substitute the measured chromatographic data into the calibration curve equation of the GPC data processing software for calculation, and the relative molecular mass and distribution range of the peptides in the sample are obtained.

[0327] (4) Salt content: Acetate detection method: Weigh 0.2g of the dried sample of the bacterial protein treatment solution to an accuracy of 0.0001g, add 40mL of glacial acetic acid to dissolve the sample, and titrate with a perchloric acid standard titration solution. Then use a potentiometer to indicate the end point. When the indicator determines the titration end point, add a few drops of crystal violet indicator solution. The solution changes from purple to bright blue-green, which is the end point of the determination. At the same time as the determination, perform a blank test using the same mass of reagent solution without adding a sample according to the same steps as the determination.

[0328] The mass fraction w of acetate in the above detection method is expressed in %, and is calculated according to the following formula:

[0329]

[0330] In the formula, v 0 The volume of perchloric acid standard titration solution consumed in the blank test, in milliliters (mL);

[0331] v 1 The volume of the perchloric acid standard drop solution consumed by the sample, in milliliters (mL);

[0332] c is the exact value of the concentration of the standard drop of perchloric acid solution, in moles per liter (mol / L);

[0333] M is the numerical value of the molar mass of acetate in grams per mole (g / mol) (M=82.03);

[0334] m is the mass of the sample in grams (g).

[0335] Lactate detection method: weigh about 0.3g of bacterial protein treatment solution, accurate to 0.0001g, then add 10mL of acetic anhydride and 50mL of glacial acetic acid to mix, let stand for about 20min after mixing evenly, add 1 drop of crystal violet indicator solution to the mixed solution, titrate with perchloric acid standard titration solution, titrate until the solution turns blue-green and does not fade within 30s, which is the titration end point, and perform a blank test to correct the titration result. The calculation method is the same as that of acetate, and the test result is based on the arithmetic mean of the parallel determination results. The absolute difference of the parallel determination results shall not exceed 0.5%.

[0336] Phosphate detection method: The detection method described in GB 5009.256-2016 Determination of multiple phosphates in food was used for detection. 2.5 g of bacterial protein treatment solution was weighed for extraction and purification, potassium hydroxide solution was used as eluent and an anion exchange column was used for separation, and a conductivity detector was used for detection, and the retention time was used for qualitative analysis, and then the external standard method was used for quantitative analysis.

[0337] (5) Nucleotides: Weigh 2.5 g of bacterial protein treatment solution and hydrolyze it with 20% perchloric acid at 100°C for 60 min. Then, use high performance liquid chromatography (HPLC) to analyze the bases of the five nucleotides in the sample. Assuming that the molar fraction of each nucleotide is the same as the molar fraction of its corresponding nucleobase, the weight content of the total nucleotides in the sample can be calculated based on this assumption.

[0338] (6) Antioxidant activity: The total antioxidant capacity (T-AOC) kit (ABTS method) (Nanjing Jiancheng Bioengineering Institute) was used for testing. The operation was carried out according to the instructions of the kit.

[0339] (7) Antibacterial activity: The bactericidal activity of the protein mash hydrolysate was evaluated by plate spreading experiment using Escherichia coli (E. coli) and Listeria monocytogenes (L. monocytogenes) as typical models of Gram-negative bacteria and Gram-positive bacteria, respectively.

[0340] (8) Small peptide structure analysis: The bacterial protein treatment solution was subjected to peptide sequencing based on the LC-MS / MS system. The mass spectrometry raw file was analyzed for peptide sequence using the PEAKSDe novo analysis method, and the bioactive peptides were identified using QSAR analysis.

[0341] The results of the above measurements are shown in the following table.

[0342] Table 1 The composition ratio of each component of bacterial protein treatment solution

[0343]

[0344]

[0345] Table 2 Molecular weight distribution of small peptides in bacterial protein treatment solution

[0346] Molecular weight distribution range Peak area percentage, % Weight average molecular weight, Mw Number average molecular weight, Mn 5000-10000 0.34 5897 5816 3000-5000 1.31 3750 3678 2000-3000 2.48 2429 2401 1000-2000 7.85 1408 1372 500-1000 20.09 641 624 <500 67.93 357 326

[0347] The above results show that the bacterial protein treatment solution has strong antioxidant and antibacterial abilities. ABTSThe kit detected that the antioxidant capacity of the bacterial protein treatment liquid was 5.6mM, which was better than most of the raw materials of puffed floating feed on the market (generally the antioxidant capacity was 0.5mM to 2.0mM); in addition, the results of the plate coating experiment showed that the protein mash enzymatic hydrolyzate could reduce the survival rate of E. coli from 95.0% to 20.5%, and the survival rate of L. monocytogenes from 94.1% to 40.2%, which indicated that the bacterial protein treatment liquid had strong antibacterial activity. In addition, the QSAR analysis results showed that the peptide sequences with biological activity in the bacterial protein treatment liquid were small molecule peptides such as FLRF, VDFF, LRFL, and RLLF.

[0348] 2. According to the determination content of Experiment 1, the weight contents of peptide segments in the bacterial protein treatment solutions of Example 2, Example 3 and Comparative Examples 1 to 3 were statistically analyzed, and the results are shown in Table 3.

[0349] Table 3 Peptide weight content of bacterial protein treatment solution in Examples 1 to 3 and Comparative Examples 1 to 3

[0350]

[0351] As can be seen from Table 3, the embodiment of the present application provides a method for treating bacterial protein mash, which combines vacuum treatment, wall breaking treatment, neutralization reaction treatment and enzymatic hydrolysis reaction and other operations. Through precise step control and optimized process parameters, the content of peptide substances in the bacterial protein mash is effectively increased to more than 25%, providing strong support for the high-value utilization of bacterial protein.

[0352] 2. Experiments related to expanded floating feed:

[0353] 1. The puffed floating feeds of Examples 4 to 6 and Comparative Examples 4 to 6 were collected, and the puffing rate, dissolution loss rate, and floating water rate were measured respectively. The results showed that the puffing rate of these puffed floating feeds was greater than 1.8, the dissolution loss rate was ≤5%, and the floating water rate was 100%, which indicated that these puffed floating feeds met the quality requirements of low-starch puffed floating feeds.

[0354] 2. Application of expanded floating feed in largemouth bass feed:

[0355] The puffed floating feeds of Examples 4 to 8 (the weight content of crude protein is 36%, the weight content of crude fat is 1.35%) and the puffed floating feeds of Comparative Examples 4 to 6 were directly used in a largemouth bass breeding experiment, wherein Comparative Example 4 was used as a control group (fish meal group, the weight content of crude protein is 68.96%, the weight content of crude fat is 8.04%).

[0356] The breeding experiment was carried out at the Nankou pilot base of the Chinese Academy of Agricultural Sciences. The largemouth black bass fry used in the experiment went through a 15-day adaptation period in the circulating water system to adapt to the formal breeding environment. During the adaptation period, they were fed twice a day, and the puffed floating feed used was a commercial puffed floating feed with a crude protein content of 52% and a crude fat content of 12%. Before the feeding experiment of largemouth black bass began, 960 healthy and similar-sized fry (initial weight of 11.34g±0.01g) were randomly assigned to 32 breeding circulation barrels (the volume of the circulation barrel was 280L), 30 in each breeding circulation barrel. At the same time, the puffed floating feeds of Examples 4 to 8 and Comparative Examples 4 to 6 were randomly assigned to the breeding circulation barrels, and four replicates were set for each group of feed. During the experiment, artificial feeding was performed until the stomach was obviously full, and the feeding time was twice a day: 8:30 to 9:30 in the morning and 5:30 to 6:30 in the afternoon for 10 weeks. The experimental conditions were based on a photoperiod of 10 hours of light and 14 hours of darkness (with a light intensity of 400 lx). Continuous oxygenation was provided in each aquaculture circulation tank, and water quality parameters were strictly controlled to keep the dissolved oxygen content in the aquaculture circulation tank above 6.0 mg / L, the pH value at 7.0-8.0, and the NH4-N content below 0.3 mg / L.

[0357] At the end of the 10-week breeding cycle, sampling was performed again. First, all the fish in the breeding cycle barrels were fasted for 24 hours and then weighed to calculate the final average weight and specific growth rate. The feed coefficient was calculated by recording the feed intake. One day before the end of the experiment, the hindgut contents of each largemouth bass were collected and stored at -80°C for analysis of intestinal flora. The chyme of each group was subjected to 16SrRNA high-throughput gene sequencing, and the sequencing region was the V3-V4 region. The OUT number of each group was obtained by sequencing. These results are shown below.

[0358] Table 4 Effects of different expanded floating feeds on the growth performance of largemouth bass ( n=4)

[0359]

[0360] Note: Different letters in the same column of Table 4 indicate significant differences (P<0.05).

[0361] From the data in Table 4, it can be seen that the expanded floating feed formed by using bacterial protein treated liquid to replace part of the fish meal can significantly increase the terminal body weight and specific growth rate of largemouth seabass (P<0.05). In addition, the expanded floating feed can also increase the feed intake of largemouth seabass and significantly reduce the feed coefficient (P<0.05).

[0362] Table 5 Effects of different expanded floating feeds on hindgut microorganisms of largemouth bass ( n=6)

[0363]

[0364]

[0365] Note: Different letters in the same column in Table 5 indicate significant differences (P<0.05).

[0366] From the data in Table 5, it can be seen that the expanded floating feed formed by using bacterial protein treated liquid to replace part of the fish meal can significantly increase the abundance and diversity of hindgut microorganisms of largemouth seabass (P<0.05), which helps to improve the intestinal health of largemouth seabass.

[0367] In summary, the embodiments of the present application provide a method for treating bacterial protein mash, which combines vacuum treatment, wall breaking treatment, neutralization reaction treatment, and enzymatic hydrolysis reaction. Through precise step control and optimized process parameters, the content of peptide substances in the bacterial protein mash is effectively increased to more than 25%, providing strong support for the high-value utilization of bacterial protein.

[0368] In addition, an embodiment of the present application provides a method for treating bacterial protein mash, which can be used to recycle the bacterial protein mash of ethanol Clostridium produced by biological fermentation of industrial tail gas, reduce the wastewater discharge of the bacterial protein mash, and fully recover the bacterial protein of ethanol Clostridium; in addition, the neutralization reaction of the treatment method can reduce the fermentation odor of the bacterial protein mash, and fully release the processing characteristics and nutritional characteristics of the bacterial protein of ethanol Clostridium.

[0369] In addition, an embodiment of the present application provides an expanded floating feed, which can use the bacterial protein processed liquid obtained by the processing method as a raw material of the expanded floating feed, and can utilize the metabolic products of the bacterial protein mash as resources.

[0370] In addition, an embodiment of the present application provides an expanded floating feed, which uses the metabolites of bacterial protein mash as raw materials, and can improve the feed intake of animals and the health of intestinal microorganisms of animals.

[0371] In addition, an embodiment of the present application provides a method for preparing an extruded floating feed. The method can reduce the starch content of the extruded floating feed and the amount of water used in the tempering stage through multiple conditioning treatments and using bacterial protein treated liquid as a raw material to replace the fish meal component of the extruded floating feed, thereby reducing the production energy consumption of the extruded floating feed.

[0372] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. It will be apparent to those skilled in the art that various modifications to these embodiments are possible, and the general principles defined in the present application can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown in the present application, but will conform to the widest range consistent with the principles and novel features applied for by the present application.

Claims

1. A method for treating bacterial protein mash, the method comprising: The bacterial protein mash is vacuum concentrated to obtain concentrated protein mash; The concentrated protein mash is subjected to cell wall breaking treatment to obtain a concentrated protein mash containing bacterial fragments; Using an alkaline solution to neutralize the concentrated protein mash containing bacterial fragments to obtain a concentrated protein reaction solution; The concentrated protein reaction liquid is subjected to enzymatic hydrolysis and enzyme inactivation treatment in sequence using a composite enzyme system to obtain a proteolytic reaction liquid; wherein the raw materials of the composite enzyme system include lysozyme, alkaline protease, nuclease and flavor protease; The proteolysis reaction solution is purified to obtain a bacterial protein treatment solution.

2. According to the treatment method of claim 1, the mass m1 of the lysozyme, the mass m2 of the alkaline protease, the mass m3 of the nuclease and the mass m4 of the flavor protease satisfy the relationship: m1:m2:m3:m4≥1:1:1:

1.

3. According to the processing method of claim 2, the mass m2 of the alkaline protease, the mass m4 of the flavor protease and the weight m5 of the dry matter of the concentrated protein reaction solution satisfy the relationship: (m2+m4) / m5=(1-7):

100.

4. The treatment method according to claim 1, wherein the temperature of the enzymatic hydrolysis reaction is 30°C to 50°C, and the time of the enzymatic hydrolysis reaction is 3h to 7h; and / or The temperature of the enzyme inactivation treatment is 70° C. to 100° C., and the time of the enzyme inactivation treatment is 5 min to 10 min.

5. The treatment method according to claim 1, wherein the pressure of the vacuum concentration is 0.07 MPa to 0.09 MPa, and the temperature of the vacuum concentration is 30° C. to 70° C.; and / or The mass concentration of bacterial protein in the concentrated protein mash is 60 g / L to 80 g / L.

6. The treatment method according to claim 1, wherein the pressure of the cell wall breaking treatment is 40 MPa to 150 MPa; and / or The end point acid-base of the neutralization reaction is 9-11.

7. The processing method according to claim 1, wherein the proteolysis reaction liquid is purified to obtain a bacterial protein processing liquid, comprising the steps of: Filtering the protein hydrolysis reaction solution to obtain a protein filtrate; Desalting the protein filtrate to obtain a desalted protein solution; The desalted protein solution is subjected to vacuum concentration using a composite gas and an adsorbent material to obtain a desalted protein concentrate; The desalted protein concentrate is sterilized to obtain a bacterial protein treated solution.

8. The method according to claim 7, wherein the composite gas comprises carbon dioxide and / or nitrogen; when the composite gas comprises carbon dioxide, the input flow rate of the carbon dioxide is 1% to 5% of the total flow rate of the composite gas; when the composite gas comprises nitrogen, the input flow rate of the nitrogen is 1% to 5% of the total flow rate of the composite gas; and / or The mass m6 of the adsorption material and the mass m7 of the desalted protein solution satisfy the relationship: m6:m7≥1:

100.

9. A system for processing bacterial protein mash, the system being adapted to the processing method according to any one of claims 1 to 8, the processing system comprising: A first vacuum concentration system (1), comprising a bacterial protein mash buffer tank (11), a first vacuum concentration device (12) and a concentrated protein mash buffer tank (13), wherein the discharge port of the bacterial protein mash buffer tank (11) is connected to the feed port of the first vacuum concentration device (12), and the discharge port of the first vacuum concentration device (12) is connected to the concentrated protein mash buffer tank (13); A high-pressure homogenizer (2), wherein the discharge port of the concentrated protein mash buffer tank (13) is connected to the feed port of the high-pressure homogenizer (2) to achieve a wall-breaking treatment of the concentrated protein mash; The enzymolysis system (3) comprises a batching tank (31), an alkali solution feeding pipe (33) and an enzymolysis tank (32), wherein the feed port of the batching tank (31) is connected to the discharge port of the high-pressure homogenizer (2), the discharge port of the batching tank (31) is connected to the feed port of the enzymolysis tank (32), and the discharge port of the alkali solution feeding pipe (33) is connected to the liquid inlet of the enzymolysis tank (32), so that the concentrated protein mash undergoes a neutralization reaction and an enzymolysis reaction to obtain a protein hydrolysis reaction liquid; The purification treatment section is connected to the discharge port of the enzymolysis tank (32) to purify the protein hydrolysis reaction liquid to obtain a bacterial protein treatment liquid.

10. The processing system according to claim 9, wherein the purification processing section comprises: A filter (4), an electrodialysis system (5), a second vacuum concentration system (6) and a sterilization device (7); The feed port of the filter (4) is connected to the discharge port of the enzymolysis tank (32); The electrodialysis system (5) comprises an electrodialysis device (51) and a desalted liquid temporary storage tank (52); the feed port of the electrodialysis device (51) is connected to the discharge port of the filter (4) so ​​that the protein hydrolysis reaction liquid is desalted to obtain a desalted protein liquid; the feed port of the desalted liquid temporary storage tank (52) is connected to the feed port of the electrodialysis device (51) so as to store the desalted protein liquid; The second vacuum concentrating system (6) comprises a second vacuum concentrating device (61), a gas conduit (62), an adsorption material feed pipe (63) and a desalted protein material tank (64); the feed port of the second vacuum concentrating device (61) is connected to the discharge port of the electrodialysis device (51); the gas conduit (62) is connected to the gas inlet of the second vacuum concentrating device (61); the adsorption material feed pipe (63) is connected to the feed port of the second vacuum concentrating device (61); the feed port of the desalted protein material tank (64) is connected to the discharge port of the second vacuum concentrating device (61); the discharge port of the desalted protein material tank (64) is connected to the sterilization device (7) to sterilize the desalted protein concentrate.

11. An expanded floating feed, comprising a bacterial protein treatment liquid obtained by the treatment method according to any one of claims 1 to 8.

12. The puffed floating feed according to claim 11, wherein the raw materials of the puffed floating feed include, by weight, 8 to 28 parts of the bacterial protein treatment liquid, 20 to 30 parts of fish meal, 53 to 56 parts of solid additives, 8.5 to 9.0 parts of compound oil, 1.4 to 2.2 parts of auxiliary materials, and ≥ 1 part of premix.

13. A method for preparing the expanded floating feed according to any one of claims 11 or 12, the method comprising: The fish meal, the solid additive, the compound oil, the auxiliary materials and the premix are mixed to obtain a solid matrix; The bacterial protein treatment liquid obtained by the treatment method according to any one of claims 1 to 8 is subjected to a first conditioning using a solvent to obtain a liquid phase matrix; Mixing the liquid matrix and the solid matrix to obtain a mixed raw material; The mixed raw material is subjected to a second conditioning to obtain a feed raw material; The feed raw materials are sequentially extruded, dried and sprayed with oil to obtain expanded floating feed particles.

14. The method according to claim 13, wherein the mass m8 of the bacterial protein treatment solution and the mass m9 of the solvent satisfy the relationship: m8:m9=(8-28):(17.25-7.36); and / or The mass of the solvent of the liquid phase matrix is ​​less than or equal to 70% of the mass of the liquid phase matrix.

15. The method according to claim 13, wherein the temperature of the second tempering is 90°C to 95°C, and the time of the second tempering is 8 min to 12 min; and / or The extrusion temperature is 120°C to 150°C, and the extrusion pressure is 3MPa to 5MPa; and / or The drying temperature is 95° C. to 103° C., and the drying time is 1 h to 2 h.

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