Preparation method of enzymolysis fairy shrimp pulp for feed

Abstract

The invention discloses a preparation method of enzymolysis fairy shrimp pulp for feed. The preparation method comprises the following steps: directly preparing low-temperature minced fairy shrimps by taking frozen fairy shrimp products as raw materials; transferring the low-temperature surimi into a fermentation container, and uniformly heating to a fermentation temperature for compound enzyme fermentation; in the fermentation process, an emulsification pump is synchronously adopted for first circulation emulsification; performing enzymolysis to obtain enzymolysis insect pulp; performing high-temperature sterilization on the enzymolysis worm pulp to obtain sterile worm pulp; reducing the temperature of the sterile insect pulp to medium temperature, adding a preservative and an emulsifier, and performing second circulation emulsification and homogenization by adopting an emulsification pump in the natural cooling process to obtain sterile homogenized insect pulp; and cooling the sterile homogenized fairy shrimp pulp to room temperature, stopping emulsifying and homogenizing, and sieving to obtain the enzymolysis fairy shrimp pulp product for the feed. The digestion and absorption rate of fairy shrimp protein is remarkably improved through the enzymolysis process, the nutritional value of the feed is fully utilized, meanwhile, the uniformity and stability of the product are high, the super-long storage life of 90 days can be achieved under the sealed, shady and cool dark conditions, and storage and transportation are convenient.

Description

Technical Field

[0001] The invention belongs to the field of animal feed, relates to a preparation method of aquatic animals, and particularly relates to a preparation method of enzymatically hydrolyzed Artemia slurry used for aquatic feed. Background Art

[0002] Artemia Salina, also known as Artemia salina, is a crustacean widely distributed in high-salt environments such as salt lakes and salt marshes. Due to its high nutritional value, short growth cycle and strong adaptability, Artemia salina and its eggs are widely used in aquaculture, especially as a starter feed for aquatic animals such as fish and shrimp. Artemia salina is rich in protein, amino acids, unsaturated fatty acids, vitamins and trace elements, etc., and plays an important role in promoting the growth and development of aquatic animals.

[0003] Traditionally, Artemia can be directly fed fresh or processed into dry powder for use. Although Artemia has important application value in aquaculture, in the process of realizing the present invention, the inventors found that the prior art has at least one of the following technical problems:

[0004] a) The absorption and utilization rate of protein and other nutrients in feed processed by traditional methods, especially in dry powder form, is relatively low.

[0005] b) Artemia bodies that have not been properly handled may carry pathogens, and direct use may pollute water quality and increase the risk of disease in farmed animals.

[0006] c) If Artemia worms are fed directly in live form or in frozen form, their remains and incompletely digested parts will easily settle at the bottom of the water, causing water quality to deteriorate.

[0007] d) Liquid feed is easy to stratify, affecting its stability and use effect; solid feed is not well dispersed in water, affecting the uniform feeding of feed.

[0008] e) Traditional drying methods will lead to the loss of some nutrients in Artemia, especially volatile components. Summary of the invention

[0009] In view of this, the object of the present invention is to provide a new preparation method of enzymatically hydrolyzed Artemia slurry for feed, which improves the utilization rate of Artemia protein through enzymatic hydrolysis technology, and solves the problem of easy stratification of Artemia slurry through specific emulsification and preservation treatment, while retaining the nutritional components of Artemia, improving palatability, and providing a safe and efficient feed for aquaculture.

[0010] The inventor has continuously innovated and reformed through long-term exploration and attempts, as well as multiple experiments and efforts, to solve the above technical problems. The technical solution provided by the present invention is to provide a method for preparing enzymatically hydrolyzed Artemia slurry for feed, comprising the following steps in sequence:

[0011] S1. Using frozen Artemia as raw material to directly prepare low-temperature insect paste;

[0012] S2, moving the low-temperature insect paste to a fermentation container, uniformly heating it to the fermentation temperature for compound enzyme fermentation; during the fermentation process, an emulsification pump is used to perform the first cycle of emulsification to obtain enzymatic insect paste;

[0013] S3, the enzymatically hydrolyzed insect pulp is sterilized at high temperature to obtain sterile insect pulp;

[0014] S4, lowering the temperature of the sterile insect slurry to a medium temperature, adding a preservative and an emulsifier, and during the natural cooling process, using an emulsification pump to perform a second cycle of emulsification and homogenization to obtain a sterile homogenized insect slurry;

[0015] S5. After the sterile homogenized worm slurry has cooled to room temperature, the emulsification and homogenization are stopped, and the slurry is sieved to obtain the enzymatic hydrolyzed Artemia worm slurry product for feed.

[0016] Preferably, the Artemia is an adult.

[0017] Preferably, the low temperature is 0-4°C, the fermentation temperature is 55±2°C, the medium temperature is 50-70°C, and the high temperature is 100-121°C.

[0018] Preferably, the high temperature sterilization time is 10 to 20 minutes.

[0019] Preferably, the high temperature sterilization duration is 15 minutes.

[0020] The overall technical concept of the present invention "a method for preparing enzymatically hydrolyzed Artemia slurry for feed" is to convert the frozen Artemia into an aquatic feed with high nutritional value and easy to store and use through a series of finely controlled biological, chemical and physical treatment steps.

[0021] Low-temperature worm paste is made by directly crushing the frozen Artemia at a low temperature of 0-4°C, which maintains the integrity and biological activity of the nutrients in the Artemia raw material, while avoiding protein denaturation and destruction of nutrients that may be caused by high temperature. Low-temperature treatment helps to maintain the freshness and flavor of the raw materials and provides a mild starting condition for the subsequent enzymatic hydrolysis step.

[0022] Compared with the prior art, the enzymatic hydrolyzed Artemia slurry obtained by the method of the present invention has significant technical effects:

[0023] First, the digestion and absorption rate of Artemia protein is significantly improved through the enzymatic hydrolysis process, so that the nutritional value of the feed can be fully utilized. Secondly, the high-temperature sterilization step ensures the hygiene and safety of the product and avoids the risk of contamination by pathogens. Thirdly, by adding preservatives and emulsifiers at medium temperature and completing the second cycle of emulsification and homogenization during natural cooling, the uniformity and stability of the product are achieved, while giving the product a good taste and flavor. Finally, this method also ensures that the product can achieve an ultra-long shelf life of 90 days under sealed, cool, and light-proof conditions, which is convenient for storage and transportation, greatly improving the practicality and economic value of Artemia slurry as aquatic feed.

[0024] On the basis of the above technical solution, the present invention can also be improved as follows:

[0025] Furthermore: in step S2, the rotation speed of the emulsification pump is 1200-2000 rpm.

[0026] Preferably, in step S2, the rotation speed of the emulsification pump is 1500 rpm.

[0027] Compared with the prior art, the beneficial effects of adopting the above further technical solution are:

[0028] The first cycle of emulsification is carried out synchronously during the compound enzyme fermentation process, and the speed of the emulsification pump is controlled at 1200-2000 rpm. This step fully mixes the components decomposed during the fermentation process through high-speed stirring to form a uniform suspension, preventing the sedimentation and stratification of the raw material components, thereby improving the enzymatic hydrolysis efficiency and product quality. The emulsification process can also improve the texture and taste of the final product, making it more suitable as aquatic feed.

[0029] The purpose of the first cycle of emulsification during the complex enzyme fermentation stage is to begin to form a stable emulsion while initially decomposing the Artemia feedstock. The relatively low speed (1500 rpm) helps to gently mix the feedstock and complex enzyme in the initial stage, avoiding excessive shearing that may cause structural damage to the feedstock. The emulsification at this stage is mainly to ensure the uniformity and efficiency of the enzymatic hydrolysis reaction, while beginning to form a stable emulsion system. The lower speed also helps to maintain the integrity of larger particles in the feedstock, laying the foundation for subsequent high temperature treatment and further emulsification.

[0030] On the basis of the above technical solution, the present invention can also be improved as follows:

[0031] Furthermore: in step S4, the rotation speed of the emulsification pump is 1500-2500 rpm.

[0032] Preferably, in step S4, the rotation speed of the emulsification pump is 2500 rpm.

[0033] Preferably, the time for naturally cooling to room temperature is 30 to 80 minutes.

[0034] Compared with the prior art, the beneficial effects of adopting the above further technical solution are:

[0035] The second cycle of emulsification and homogenization is carried out during the natural cooling process, and the speed of the emulsification pump is controlled at 1500-2500 rpm. The technical function of this step is to further refine the particles of the emulsion while cooling, and improve the homogeneity and stability of the product. By homogenizing in a wider temperature range, it helps to gradually eliminate the unevenness caused by temperature changes, ensuring that the product maintains a stable emulsified state during the cooling process, thereby obtaining a more delicate and uniform final product, and improving the quality and application performance of the product.

[0036] The second cycle of emulsification and homogenization during the natural cooling process is carried out after high-temperature sterilization and the addition of preservatives and emulsifiers at medium temperature. The speed of the emulsification pump at this stage is relatively high (2500 rpm) in order to achieve a more delicate and uniform emulsification effect during the final cooling process. The high speed helps to further reduce the particle size of fat and oil droplets in the emulsion, thereby improving the stability and uniformity of the emulsion. In addition, the higher speed of the emulsification pump helps to quickly disperse the preservatives and emulsifiers during the cooling process, ensuring that they are evenly distributed throughout the product, improving the texture and taste of the final product, and extending the shelf life of the product.

[0037] By precisely controlling the emulsification process, the nutritional value, stability and sensory quality of Artemia slurry can be significantly improved.

[0038] On the basis of the above technical solution, the present invention can also be improved as follows:

[0039] Furthermore: the components of the emulsifier include 60% to 70% maltodextrin and 30% to 40% modified starch by weight percentage.

[0040] Preferably, the components of the emulsifier include 60% maltodextrin and 40% modified starch by weight.

[0041] Preferably, the modified starch comprises hydroxypropyl distarch phosphate or xanthan gum.

[0042] Preferably, the modified starch is hydroxypropyl distarch phosphate or xanthan gum.

[0043] Preferably, the added amount of the emulsifier is 0.3% to 1.0% of the weight of the enzymatically hydrolyzed insect slurry.

[0044] Compared with the prior art, the beneficial effects of adopting the above further technical solution are:

[0045] The emulsifier is added at the medium temperature stage and is composed of 60% to 70% maltodextrin and 30% to 40% modified starch. The added amount is 0.3% to 1.0% of the weight of the enzymatic insect pulp. The technical function of the emulsifier is to increase the stability of the product by improving the emulsification properties and prevent oil-water separation, thereby improving the uniformity of the product and extending the shelf life. The emulsifier helps to form small and evenly distributed oil droplets, improving the digestion and absorption characteristics of the product.

[0046] On the basis of the above technical solution, the present invention can also be improved as follows:

[0047] Furthermore, the components of the preservative include, by weight percentage, 65% to 75% edible crude salt, 20% to 30% citric acid, and 3% to 5% calcium propionate.

[0048] Preferably, the added amount of the preservative is 0.3% to 1.0% of the weight of the enzymatically hydrolyzed insect pulp.

[0049] Compared with the prior art, the beneficial effects of adopting the above further technical solution are:

[0050] The preservative is added after the temperature of the sterile worm slurry drops to medium temperature. Its components, by weight percentage, include 65% to 75% edible crude salt, 20% to 30% citric acid, and 3% to 5% calcium propionate. The main technical function of the preservative is to inhibit the growth of microorganisms and extend the shelf life of the product. Citric acid and calcium propionate have antibacterial properties and can reduce the growth of bacteria and mold, while edible crude salt helps to regulate the osmotic pressure of the product and further inhibit the survival of microorganisms.

[0051] On the basis of the above technical solution, the present invention can also be improved as follows:

[0052] Furthermore: the complex enzyme includes papain and bromelain.

[0053] Preferably, the complex enzyme is papain and bromelain.

[0054] Preferably, the enzymatic activity of the papain is 2 million units (U / g), and the added amount is 0.08% of the weight of the insect paste.

[0055] Preferably, the enzymatic activity of the bromelain is 500,000 units (U / g), and the added amount is 0.1% of the weight of the insect paste.

[0056] Preferably, the fermentation time is 120 min.

[0057] Compared with the prior art, the beneficial effects of adopting the above further technical solution are:

[0058] By adopting the above further technical scheme, by accurately selecting and matching papain and bromelain as composite enzymes, and optimizing enzyme activity and addition amount, the present invention can achieve more efficient and specific enzymolysis, thereby significantly improving the conversion rate of protein in Artemia raw materials and releasing more peptides and amino acids with high nutritional value. The high enzymatic activity (2 million U / g) and precise addition amount (0.08% of the weight of shredded worms) of papain help to efficiently decompose protein, while the addition of bromelain (500,000 U / g) enhances the hydrolysis ability of specific protein structures, and its addition amount (0.1% of the weight of shredded worms) ensures the adequacy and thoroughness of the enzymolysis process. In addition, extending the fermentation time to 120 minutes allows the enzymolysis reaction to be more complete and further releases nutrition. These improvements comprehensively enhance the nutritional value and digestibility of the product, while ensuring the efficiency and stability of the production process. Therefore, compared with the prior art, the present invention not only improves the nutritional value and application effect of Artemia worm paste, but also helps to reduce production costs, improve economic benefits, and enhance the market competitiveness of products.

[0059] On the basis of the above technical solution, the present invention can also be improved as follows:

[0060] Furthermore, the enzymatic hydrolyzed Artemia slurry product for feed is sealed and stored in a cool, dark place with a shelf life of 1 to 90 days.

[0061] Compared with the prior art, the beneficial effects of adopting the above further technical solution are:

[0062] The ability of enzymatically hydrolyzed Artemia products to be stored for up to 90 days is of great significance in practical applications. First, a longer shelf life means that the product can be produced, transported and used within a more relaxed time frame, reducing the need for immediate processing and distribution. This not only reduces logistics pressure, but also provides greater flexibility and scope for the sale and distribution of products. Second, for farmers and feed manufacturers, this stability means that they can manage inventory more effectively and reduce losses and waste caused by insufficient feed freshness. In addition, a longer shelf life also helps to maintain the competitiveness of products in the feed market because it can meet the needs of farmers in different regions and of different sizes. Finally, from the perspective of quality assurance, a 90-day shelf life also means that the product can maintain its nutritional value and flavor characteristics during this period, ensuring the breeding effect and economic benefits of the end user. In short, extending the shelf life significantly improves the market adaptability and user convenience of the product, and plays a positive role in promoting the stable development of the feed industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0064] Figure 1 This is a physical picture of the storage state of the enzymatic hydrolyzed Artemia slurry for feed in Example 1.

[0065] Figure 2 This is a schematic diagram of the overhead structure of the feeding trough in the shrimp feeding attractant experiment. DETAILED DESCRIPTION

[0066] The following describes the invention in conjunction with specific embodiments.

[0067] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention.

[0068] In the present invention, unless otherwise specified, all equipment and raw materials can be purchased from the market or are commonly used in the industry. The methods in the following embodiments, unless otherwise specified, are conventional methods in the art.

[0069] Example 1

[0070] The preparation method of the enzymatic hydrolyzed Artemia slurry for feed described in this embodiment has the following specific steps:

[0071] (1) The frozen plate of Artemia adult worms is directly put into a crusher for crushing without thawing to obtain low-temperature worm paste. The temperature of the low-temperature worm paste is controlled at 0-4°C. This step is intended to keep the nutritional components of Artemia intact as much as possible under low temperature conditions.

[0072] (2) Pump the low-temperature Artemia into a stainless steel enzymatic hydrolysis tank, stir with a paddle and heat the tank until the material temperature reaches 55°C, with the temperature fluctuation range controlled within 2°C. Temperature control is crucial for the subsequent enzymatic hydrolysis reaction.

[0073] (3) Adding a composite enzyme to the enzymatic hydrolysis tank for enzymatic hydrolysis to obtain enzymatic hydrolyzed insect slurry. Among them, the enzymatic activity of papain is 2 million units (U / g), and the added amount is 0.08% of the weight of the Artemia slurry; the enzymatic activity of bromelain is 500,000 units (U / g), and the added amount is 0.10% of the Artemia slurry. Maintain the Artemia slurry temperature at 55°C ± 2°C for 120 minutes of enzymatic hydrolysis; at the same time, turn on the emulsification pump at a speed of 1500 rpm for the first cycle of emulsification to ensure a uniform enzymatic hydrolysis process.

[0074] (4) After the enzymatic hydrolysis is completed, the Artemia slurry is heated to 100°C and maintained for 15 minutes to inactivate the enzymes and sterilize the slurry to ensure that any pathogens that may exist are killed and the enzymatic hydrolysis reaction is terminated to obtain a sterile slurry.

[0075] (5) The sterile insect slurry is naturally cooled or water-cooled to 60°C, and a preservative and an emulsifier are added to perform a second cycle of emulsification and homogenization to obtain a sterile homogenized insect slurry. The composition of the preservative is 71% edible crude salt, 25% citric acid, and 4% calcium propionate, and the added amount is 9% of the weight of the sterile insect slurry. The composition of the emulsifier is 65% maltodextrin and 35% modified starch, and the added amount is 0.4% of the weight of the Artemia slurry. The speed of the emulsification pump is 2500 rpm to achieve a more delicate emulsification effect. During the second cycle of emulsification and homogenization, the sterile insect slurry is naturally cooled, and the cooling time is more than 30 minutes and less than 1 hour.

[0076] (6) After the sterile homogenized insect slurry is cooled to room temperature, it is pumped out, passed through a vibrating screen to remove impurities, and then packed into barrels. Ensure that the product is stored in a sealed, cool, and light-proof environment to maintain product quality and extend the shelf life. The shelf life is not recommended to exceed 90 days.

[0077] See also Figure 1 When the enzymatic hydrolyzed Artemia worm pulp product was stored for 85 days, there was still no stratification phenomenon.

[0078] A series of nutrient content tests were conducted on the enzymatically hydrolyzed Artemia slurry obtained in this example, as shown in the following table.

[0079] Table 1 Nutrient composition index of enzymatic hydrolysis of Artemia spp.

[0080] index Numeric index Numeric index Numeric Moisture 77.0％ calcium 0.2％ Coarse ash 8.3％ Crude protein 10.1％ Total Phosphorus 0.8％ Crude fat 1.8％ Acid soluble protein 79.8％ Salt 6.0％ VBN 65.6mg / Kg .

[0081] In the above Table 1, the moisture content was detected according to GB / T 6435-2014 Determination of moisture and other volatile substances in feed; the crude protein content was detected according to GB / T 6432-2018 Determination of crude protein in feed; the crude fat content was detected according to GB / T 6433-2006 Determination of crude fat in feed; the crude ash content was detected according to GB / T 6438-2007 Determination of crude ash in feed; the calcium content was detected according to GB / T 6436-2018 Determination of calcium in feed; the total phosphorus content was detected according to GB / T6437-2018 Determination of total phosphorus in feed by spectrophotometry; the salt content was detected according to GB / T 6439-2007 Determination of chloride in feed; and the VBN content was detected according to GB / T32141-2015 Determination of volatile basic nitrogen in feed.

[0082] Among all the above indicators, acid-soluble protein generally refers to small peptides and amino acids with a molecular weight of 10,000 Daltons, and its content accounts for as high as 79.8% of the total protein, indicating that a large number of peptides with low molecular weight are produced after the directed enzymatic hydrolysis of the protein in Artemia, which are easy for animals to digest and absorb; and the volatile basic nitrogen (VBN) content is only 65.6 mg / kg, indicating that the content of free amino acids after enzymatic hydrolysis is limited, and the acid-soluble protein is mainly peptides, and the fish protein is not completely decomposed into free amino acids, which will not cause a large amount of nutrient loss and waste. The data in Table 1 show that enzymatic hydrolysis of Artemia slurry is a high-moisture, high-protein and low-fat feed raw material with high nutritional value and good digestibility and absorption. This feed is particularly suitable for aquatic animals and can meet their needs for protein and minerals while maintaining appropriate salt and ash levels.

[0083] In this embodiment, the enzymatic hydrolysis of Artemia slurry is as follows:

[0084] The water content in the enzymatically hydrolyzed Artemia slurry is relatively high, which is related to the water retention during the preparation process of this embodiment. The high water content helps maintain the stability and freshness of the product.

[0085] The crude protein content indicates that Artemia slurry is a good source of protein. This is particularly important for aquaculture feeds, as protein is a key nutrient for the growth and health of fish and other aquatic animals.

[0086] Acid-soluble protein refers to protein that can dissolve under acidic conditions. The proportion of 79.8% is very high, indicating that most of the protein has been enzymatically hydrolyzed into small molecule peptides and amino acids, which helps to improve the digestion and absorption rate.

[0087] The relatively low crude fat content indicates that Artemia slurry is not a major source of fat, which is beneficial for aquatic animals that require a low-fat diet.

[0088] Calcium is essential for the formation of bones and shells in aquatic animals. Although not present in high levels, calcium addition can improve the nutritional value of feed.

[0089] Phosphorus is one of the essential minerals for the growth of aquatic animals, helping to store energy and maintain cell structure. Appropriate phosphorus content helps the healthy growth of animals.

[0090] Crude ash is the inorganic matter, usually including minerals, left after a sample is burned at high temperatures. This ratio helps assess the inorganic content of a feed.

[0091] Proper salt content is essential for maintaining the osmotic pressure balance of aquatic animals. A salt content of 6.0% is suitable for the needs of most aquatic animals.

[0092] Table 2 Amino acid index of enzymatic hydrolysis of Artemia sphaerocephala pulp (wet basis)

[0093]

[0094]

[0095] .

[0096] The detection of amino acids in Table 2 above adopts "GB / T 18246-2019 Determination of Amino Acids in Feed".

[0097] The data in Table 2 show the amino acid composition of hydrolyzed Artemia slurry, which is a key indicator to measure its nutritional value as an aquatic feed raw material. In general, the hydrolyzed Artemia slurry contains a high proportion of essential and non-essential amino acids, and the total proportion of amino acids in crude protein is as high as 89.86%, indicating that its protein quality is excellent and its bioavailability is high. Specifically, glutamic acid has the highest content, reaching 1.38%, which plays an important role in the growth and health of aquatic animals, especially in the function of the nervous system and metabolic processes. At the same time, the content of lysine and leucine is also relatively high. They are essential amino acids for aquatic animals and are essential for promoting growth and maintaining health. Overall, the amino acid composition of hydrolyzed Artemia slurry indicates that it is a potential high-nutritional value feed raw material, especially suitable as a supplementary source of protein in aquatic feed.

[0098] use Figure 2 The illustrated attractant tank was used to conduct a shrimp attractant test on the enzymatically hydrolyzed Artemia slurry obtained in this example.

[0099] Figure 2 In the figure, 1 is the feeding area, 2 is the central groove, and 3 is the annular baffle.

[0100] The specific operations are as follows:

[0101] 1. Take 40 whiteleg shrimps weighing 8-10g / tail, put them in the feeding tank, and conduct the feeding experiment. Cultivate the water for 24 hours in advance, fully oxygenate and dechlorinate, control the salt content to 10‰, and keep the water temperature constant at 24-28℃.

[0102] 2. Control group a: The attractant granules are fish meal feed, 50% fish meal and 50% flour, mixed evenly, granulated and passed through a 12-16 mesh sieve; Treatment group b: The attractant granules are enzymatically hydrolyzed Artemia slurry feed, 50% enzymatically hydrolyzed Artemia slurry and 50% flour, mixed evenly, granulated and passed through a 12-16 mesh sieve.

[0103] 3. Take 32 particles of each type of attractant (about 1.0% of the weight of white shrimp), divide it into 4 portions, and place them alternately in 8 attractant areas 1. Install a video camera above the attractant tank to record the number of times white shrimp enter the attractant area 1. Entering the attractant area 1 is counted as 1 time. Experimental time: 9:00 am and 5:00 pm, repeated for 2 days, and the average of four experiments is calculated.

[0104] 4. Put the prepared white shrimp into the food trough in advance and keep it overnight. Before the experiment, collect the white shrimp in the central tank 2 of the food trough, clean the remaining feces in the food trough, temporarily pull out the oxygenator, and place the numbered food particles in the food trough 1 according to the sequence. After about 3 minutes, gently open the annular baffle 3, start recording and start the 10-minute countdown to observe the direction and feeding status of the white shrimp. After 10 minutes, count the remaining food status of each food trough (take photos and count the remaining food particles).

[0105] 5. After two feeding experiments in the morning and evening for two days, the number of times the fish entered the feeding area is shown in Table 3.

[0106] Table 3 Appetite test results

[0107] Group Number of times entering the feeding area Control group a 101 Treatment group b 121 .

[0108] In the feeding attractant experiment, the number of times shrimp entered the feeding area was used as an indicator to measure the feeding attractant effect. This indicator intuitively reflects the preference and response of shrimp to different feeding attractants. Using fish meal as the control feed, the average number of times shrimp entered the effective area in four experiments within two days was 101 times. Fish meal, as a traditional feeding attractant, has been shown to have a good feeding attractant effect on aquatic animals. Using Artemia slurry as a feeding attractant feed, the number of times shrimp entered the effective area was 121 times, which was significantly higher than the fish meal control group. By comparing the two sets of data, it can be concluded that Artemia slurry has a better feeding attractant effect than fish meal. This means that Artemia slurry, as a potential feeding attractant, can effectively attract shrimp, which may be related to its unique nutritional components and flavor. The results of this experiment show that Artemia slurry can be used as an efficient attractant in aquatic feed to increase the feeding amount and growth performance of aquatic animals such as shrimp.

[0109] Example 2

[0110] The preparation method of the enzymatic hydrolyzed Artemia slurry for feed described in this embodiment has the following specific steps:

[0111] (1) The frozen plate of Artemia adult worms is directly put into a crusher for crushing without thawing to obtain low-temperature worm paste. The temperature of the low-temperature worm paste is controlled at 0-4°C.

[0112] (2) The low-temperature Artemia muscimol was pumped into a stainless steel enzymatic hydrolysis tank, stirred with a paddle and the tank was heated until the material temperature reached 55°C, and the temperature fluctuation range was controlled within 2°C.

[0113] (3) Adding a composite enzyme to the enzymatic hydrolysis tank for enzymatic hydrolysis to obtain enzymatic hydrolyzed insect pulp. The enzymatic activity of papain is 2 million units (U / g), and the enzymatic activity of bromelain is 500,000 units (U / g), and the added amount is 0.06% of the Artemia slurry. The Artemia slurry temperature is maintained at 55°C ± 2°C for 120 minutes of enzymatic hydrolysis; at the same time, the emulsification pump is turned on at a speed of 1800 rpm for the first cycle of emulsification.

[0114] (4) After the enzymatic hydrolysis is completed, the Artemia slurry is heated to 100°C and maintained for 15 minutes to inactivate the enzymes and sterilize the slurry to ensure that any pathogens that may exist are killed and the enzymatic hydrolysis reaction is terminated to obtain a sterile slurry.

[0115] (5) The sterile insect slurry is naturally cooled or water-cooled to 60°C, and a preservative and an emulsifier are added to perform a second cycle of emulsification and homogenization to obtain a sterile homogenized insect slurry. The composition of the preservative is 71% edible crude salt, 25% citric acid, and 4% calcium propionate, and the added amount is 9% of the weight of the sterile insect slurry. The composition of the emulsifier is 65% maltodextrin and 35% modified starch, and the added amount is 0.4% of the weight of the Artemia slurry. The speed of the emulsification pump is 2000 rpm to achieve a more delicate emulsification effect. During the second cycle of emulsification and homogenization, the sterile insect slurry is naturally cooled, and the cooling time is more than 30 minutes and less than 1 hour.

[0116] (6) After the sterile homogenized insect slurry is cooled to room temperature, it is pumped out, passed through a vibrating screen to remove impurities, and then packed into barrels. Ensure that the product is stored in a sealed, cool, and light-proof environment to maintain product quality and extend shelf life.

[0117] A series of nutrient content tests were conducted on the enzymatically hydrolyzed Artemia slurry obtained in this example, using the test standard Example 1. The results are shown in Tables 4 to 5 below.

[0118] Table 4 Nutritional indexes of enzymatic hydrolysis of Artemia slurry

[0119] index Numeric index Numeric index Numeric Moisture 76.5％ calcium 0.2％ Coarse ash 8.2％ Crude protein 10.2％ Total Phosphorus 0.7％ Crude fat 1.7％ Acid soluble protein 66.7％ Salt 6.0％ VBN 75.6mg / kg .

[0120] Table 4 shows that the acid-soluble protein content accounts for 66.7% of the total protein, indicating that the enzymatic hydrolysis effect is not good; the volatile basic nitrogen (VBN) content is only 75.6 mg / kg, indicating that the free amino acid content after enzymatic hydrolysis is limited and will not cause a large amount of nutrient loss and waste.

[0121] Table 5 Amino acid index of enzymatic hydrolysis of Artemia sphaerocephala pulp (wet basis)

[0122] Amino acid index Value (%) Amino acid index Value (%) Aspartic acid 0.97 Proline 0.52 Serine 0.3 Cystine 0.05 Glutamate 1.35 Valine 0.42 Glycine 0.75 Methionine 0.22 Arginine 0.60 Lysine 0.75 Threonine 0.24 Isoleucine 0.31 Alanine 0.62 Leucine 0.62 Phenylalanine 0.22 Tyrosine 0.65 Histidine 0.11 Total of 17 amino acids 8.70 17 kinds of amino acids / crude protein 85.29％ .

[0123] Table 5 shows that the contents of 17 amino acids were slightly lower, and their total percentage in crude protein decreased.

[0124] The feeding experiment was carried out in the same manner as in Example 1. The results are shown in Table 6.

[0125] Group Number of times entering the feeding area Control group a 105 Treatment group b 109 .

[0126] The enzymatic hydrolyzed Artemia slurry obtained in the above examples was subjected to a shrimp feeding test according to the method of Example 1. The results showed that the feeding ability was improved to a certain extent compared with fish meal, but was quite different from that of Example 1.

[0127] By analyzing the data of Example 1 and Example 2, it can be seen that in Example 1 and Example 2, the change in the amount of complex enzyme has a significant effect on the nutritional components and amino acid content of Artemia slurry. Specifically, the amount of papain and bromelain in Example 2 was reduced from 0.08% and 0.10% in Example 1 to 0.06%. This reduction in dosage leads to a decrease in enzymatic hydrolysis efficiency, thereby reducing the degree to which proteins are decomposed into small molecular peptides and amino acids. This is directly reflected in the reduction in the content of acid-soluble protein (from 79.8% to 66.7%) and the reduction in the sum of 17 amino acids (from 9.09% to 8.70%). The decrease in amino acid content not only reduces the nutritional value of Artemia slurry, but may also affect its flavor and taste, which is one of the reasons why the number of Artemia slurry induction times in the induction experiment was reduced from 121 times to 109 times.

[0128] The change of the speed of the emulsification pump will also have an impact on the physical properties and phagocytosis of the Artemia slurry. In Example 2, the speed of the first cycle emulsification was increased from 1500 rpm to 1800 rpm, while the speed of the second cycle homogenization emulsification was reduced from 2500 rpm to 2000 rpm. The higher speed during the first cycle emulsification process may help to disperse the enzyme and nutrients more evenly, thereby improving the efficiency of enzymolysis. However, the lower speed during the second cycle emulsification process may reduce the shear force on the emulsion system, limiting the ability to further refine the emulsified particles. This change may have an impact on the dispersion and absorption of nutrients.

[0129] In the feeding attraction experiment, the number of feeding attractions in the control group increased from 101 to 105, and the number of feeding attractions in the treatment group decreased from 121 to 109, indicating that the relative attractiveness of the treatment group decreased, causing the shrimp to turn to the control group feed (fish meal feed).

[0130] The enzymatically hydrolyzed Artemia slurry for feed prepared in this example showed stratification after being stored for 5 days.

[0131] In the emulsifier dosage test, when maltodextrin was 80% and hydroxypropyl distarch phosphate was 20%, the enzymatic hydrolysis of Artemia slurry was left to stand for 24 hours and showed a slight stratification phenomenon. The Artemia slurry prepared by the present invention can remain uniform at room temperature and is not easy to stratify through emulsification and preservation treatment, while retaining important nutrients and food attractants such as molting hormone, astaxanthin and trimethylamine oxide.

[0132] This embodiment uses frozen Artemia spp. as raw material, which also avoids the risk of live Artemia spp. carrying pathogens and parasites to a certain extent, and is convenient for transportation and storage. Of course, in some other embodiments, live adult Artemia spp. may also be used as raw material.

[0133] In the description of the present invention, it should be understood that "-" and "~" represent the range between two values, and the range includes the endpoints. For example: "AB" represents a range greater than or equal to A and less than or equal to B. "A~B" represents a range greater than or equal to A and less than or equal to B.

[0134] In the description of the present invention, the term "and / or" herein is merely a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent three situations: A exists alone, A and B exist at the same time, and B exists alone.

[0135] In the description of the invention, the numerical values ​​of time, temperature, ratio, mass, etc. involved may be based on actual measurements, standard parameters of equipment, simplified rounding results, or within an acceptable error range, ensuring the practicability and repeatability of the invention.

[0136] In the description of the present invention, the term "about" or "approximately" is used to express the approximate value of a numerical value or range, allowing a certain error to ensure the flexibility and practicality of the description while remaining within an acceptable error range, with the maximum error range not exceeding 10% of the corresponding numerical value or numerical range.

[0137] The above are only preferred embodiments of the present invention. It should be noted that the above preferred embodiments should not be regarded as limiting the present invention, and the protection scope of the present invention should be based on the scope defined by the claims. For ordinary technicians in this technical field, several improvements and modifications can be made without departing from the spirit and scope of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A method for preparing enzymatically hydrolyzed Artemia slurry for feed, characterized in that: The following steps are included: S1. Using frozen Artemia as raw material to directly prepare low-temperature insect paste; S2, moving the low-temperature insect paste to a fermentation container, uniformly heating it to the fermentation temperature for compound enzyme fermentation; during the fermentation process, an emulsification pump is used to perform the first cycle of emulsification to obtain enzymatic insect paste; S3, the enzymatically hydrolyzed insect pulp is sterilized at high temperature to obtain sterile insect pulp; S4, lowering the temperature of the sterile insect slurry to a medium temperature, adding a preservative and an emulsifier, and during the natural cooling process, using an emulsification pump to perform a second cycle of emulsification and homogenization to obtain a sterile homogenized insect slurry; S5. After the sterile homogenized worm slurry has cooled to room temperature, the emulsification and homogenization are stopped, and the slurry is sieved to obtain the enzymatic hydrolyzed Artemia worm slurry product for feed.

2. The method for preparing enzymatically hydrolyzed Artemia slurry for feed according to claim 1, characterized in that: The low temperature is 0-4°C, the fermentation temperature is 55±2°C, the medium temperature is 50-70°C, and the high temperature is 100-121°C.

3. The method for preparing enzymatically hydrolyzed Artemia slurry for feed according to claim 1, characterized in that: In step S2, the rotation speed of the emulsification pump is 1200-2000 rpm.

4. The method for preparing enzymatically hydrolyzed Artemia slurry for feed according to claim 1, characterized in that: In step S4, the rotation speed of the emulsification pump is 1500-2500 rpm.

5. The method for preparing enzymatically hydrolyzed Artemia slurry for feed according to any one of claims 1 to 4, characterized in that: The components of the emulsifier include 60% to 70% maltodextrin and 30% to 40% modified starch by weight percentage.

6. The method for preparing enzymatically hydrolyzed Artemia slurry for feed according to claim 5, characterized in that: The added amount of the emulsifier is 0.3% to 1.0% of the weight of the enzymatically hydrolyzed insect pulp.

7. The method for preparing enzymatically hydrolyzed Artemia slurry for feed according to claim 5, characterized in that: The components of the preservative include, by weight percentage, 65% to 75% edible crude salt, 20% to 30% citric acid, and 3% to 5% calcium propionate.

8. The method for preparing enzymatically hydrolyzed Artemia slurry for feed according to claim 7, characterized in that: The added amount of the preservative is 0.3% to 1.0% of the weight of the enzymatically hydrolyzed insect pulp.

9. The method for preparing enzymatically hydrolyzed Artemia slurry for feed according to claim 1, characterized in that: The complex enzyme comprises papain and bromelain.

10. The method for preparing enzymatically hydrolyzed Artemia slurry for feed according to claim 1, characterized in that: The enzymatically hydrolyzed Artemia slurry product for feed is sealed and stored in a cool, dark place with a shelf life of 1 to 90 days.

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