Shrimp yolk powder and preparation method thereof

Abstract

The invention relates to the technical field of food processing, in particular to shrimp yellow powder and a preparation method thereof.The shrimp yellow powder is prepared from, by weight, 400-800 parts of recycled crayfish yellow, 50-75 parts of recycled water-soluble protein, 12-64 parts of salicornia herbacea extract, 2-12 parts of mung bean hull extract and 800-1600 parts of water through spray drying and grinding, and the shrimp yellow powder is prepared from, by weight, 400-800 parts of recycled crayfish yellow, 50-75 parts of recycled water-soluble protein, 12-64 parts of salicornia herbacea extract, 2-12 parts of mung bean hull extract and 800-1600 parts of water. The mass of the salicornia herbacea extract is 3-8% of the mass of the water, and the mass of the mung bean hull extract is 0.5-1.5% of the mass of the water. The prepared shrimp yellow powder is rich in nutrition, bright and glossy in color, fluffy in texture and excellent in oxidation resistance.

Description

Technical Field

[0001] The invention relates to the technical field of food processing, and in particular to a method for preparing shrimp roe powder. Background Art

[0002] Most of the crayfish are distributed in the middle and lower reaches of the Yangtze River. They are widely loved for their rich nutrition and delicious meat. The aquaculture industry has developed rapidly and the consumer market has continued to expand. They have become an important resource of freshwater shrimp in China. The processed products of crayfish can be divided into quick-frozen products, pre-prepared dishes, snack foods and deep-processed products. However, a large amount of by-products will be produced during the initial processing of crayfish, among which the by-products such as shrimp heads (including shrimp roe) and shrimp shells account for more than 70% of the raw materials. Further processing can prepare products rich in astaxanthin and protein, which have high utilization value and huge potential. At present, the processing process of finished crayfish is generally as follows: the cleaned crayfish is steamed, the shrimp heads and shrimp tails are separated after steaming, and then cooled with water. On average, 9.3 tons of water are used to produce 1 ton of crayfish products, especially in the cooking and cooling stages, where a large amount of wastewater is generated. The cooking water contains more protein, and the loss rate of shrimp roe during the cooling process is as high as 60%. The lost shrimp roe enters the cooling water. The water used in crayfish processing contains nutrients such as protein, shrimp roe, chitin, astaxanthin, lipids and trace elements. At present, there is no special recycling and processing equipment for these nutrients, resulting in waste of resources and environmental pollution, which restricts the development of the crayfish industry chain towards a green, healthy and efficient direction.

[0003] Therefore, it is urgent to develop green and efficient recycling technology for nutrients in water used in crayfish processing, and to process and utilize the recovered nutrients on an industrial scale to solve the environmental pollution problems caused by crayfish production and increase the added value of crayfish processing. Summary of the invention

[0004] In order to solve the problems existing in the background technology, the present invention provides a shrimp roe powder and a preparation method thereof, which can make the recovered shrimp roe into shrimp roe powder and retain its nutritional components.

[0005] The technical solution of the present invention to solve the above technical problems is as follows:

[0006] In the first aspect, the present invention provides a shrimp roe powder, which is obtained by spray drying and grinding the following raw materials. The raw materials include, by weight: 400-800 parts of recovered crayfish roe, 50-75 parts of recovered water-soluble protein, 12-64 parts of grass green salt horn grass extract, 2-12 parts of mung bean peel extract, and 800-1600 parts of water, and the mass of the grass green salt horn grass extract is 3%-8% of the mass of water, and the mass of the mung bean peel extract is 0.5%-1.5% of the mass of water.

[0007] In a second aspect, the present invention provides a method for preparing the above-mentioned shrimp roe powder, comprising the following steps:

[0008] S1. The recovered crayfish roe and the recovered water-soluble protein are freeze-dried to obtain freeze-dried crayfish roe and freeze-dried water-soluble protein;

[0009] S2. Adding a green salicornia extract and a mung bean peel extract to ultrapure water, standing to allow both to completely dissolve to obtain a mixed solution, adding freeze-dried crayfish roe to the mixed solution for homogenization and emulsification to make the material state uniform, and then adding freeze-dried water-soluble protein for secondary emulsification to obtain a pre-emulsion, and subjecting the pre-emulsion to ice bath ultrasonic treatment to obtain an emulsion;

[0010] S3. The emulsion is spray dried to obtain a semi-finished shrimp powder;

[0011] S4. Use air classification grinding technology to obtain shrimp roe powder of uniform size.

[0012] According to the above scheme, the homogenization conditions in step S2 are: rotation speed 6000-10000 rpm, time 5-8 min, and ice bath ultrasonic conditions: frequency 25-45 Hz, intensity 200-600 W, temperature 0-4° C., time 10 min.

[0013] According to the above scheme, high-pressure airflow spray drying is adopted in step S3, and the conditions are: inlet air temperature 130-170°C, outlet air temperature 101-110°C, peristaltic speed 20-24RPM, carrier gas flow rate 10-40L / s, and passing through 80-150 mesh sieve.

[0014] The high-pressure combined airflow spray drying technology is used to enhance the friction resistance of the emulsion and steam flow. The hot air flow rate in the airflow spray dryer is high, which can make the droplets fully contact with the hot air, evaporate the water quickly, and promote the atomization of the material in the carrier gas, thereby achieving a faster drying speed.

[0015] According to the above scheme, low-frequency shaking vacuum freeze drying is adopted in step S1, and the vacuum degree is 0.05 to 0.1 kPa, and the cold trap temperature is -45 to -80°C. The product is vacuum freeze dried for 24 to 48 hours and then taken out.

[0016] Low-altitude shaking vacuum freeze-drying technology can sublime the ice crystals in the material into gas. Through low-frequency shaking, it can enhance the heat and mass transfer efficiency of the material during the drying process, ensure that the material is fully dried from the inside out, and can maintain the color, aroma, taste, shape and freshness of the material to the greatest extent.

[0017] According to the above scheme, the conditions for air classification grinding in step S4 are a rotation speed of 4500-5500 r / min, a grinding pressure of 0.6-1.0 MPa, and the particle size range of shrimp yellow powder is 10-20 μm.

[0018] The air classification grinding technology is adopted, combining the two processes of crushing and classification. The frequency-controlled classification wheel separates the coarse and fine materials, and circulates the grinding to the target particle size. Air classification can improve the air cleaning efficiency by more than 50%, save energy and reduce emissions, and make the shrimp roe powder fluffy, without obvious agglomeration, and uniform in size. While ensuring the quality of shrimp roe powder, it can also reduce enzyme activity and oxidation loss. Therefore, the air classification grinding technology can better ensure the fiber structure, color and nutrition of shrimp roe powder.

[0019] According to the above scheme, the crayfish roe and water-soluble protein obtained by using the crayfish processing water in step S1 are recovered, and the recovery method comprises the following steps:

[0020] S1.1 The crayfish processing water is allowed to stand for stratification to obtain an upper oil layer containing solid and liquid shrimp roe components, which is a first processed product for recovering shrimp roe, and a lower aqueous solution layer, which is a second processed product for recovering water-soluble protein;

[0021] S1.2 using a hanging bag centrifuge to process the first processed product to obtain a filtrate and a semi-solid filter residue trapped in the hanging bag, recovering the filtrate and the filter residue, wherein the filter residue is a crude shrimp roe product, and the filtrate is incorporated into the second processed product separated in step S1.1 to obtain a mixed filtrate, wherein the hanging bag of the hanging bag centrifuge is provided with a hydrophilic oleophobic coating;

[0022] S1.3 The crude shrimp roe and the mixed filtrate are treated separately: the crude shrimp roe is placed in rice washing water for bubbling washing, filtered using a hanging bag centrifuge equipped with a hydrophilic and oleophobic coating, and then placed in a peracetic acid solution for ultrasonic shaking combined washing, filtered using a hanging bag centrifuge equipped with a hydrophilic and oleophobic coating to obtain recovered crayfish roe; chitosan and sodium alginate are added to the mixed filtrate to flocculate and precipitate the water-soluble protein, and filtered to obtain recovered water-soluble protein.

[0023] According to the above scheme, after the crayfish processing water is allowed to stand and separate into layers in step S1.1, the gate is opened to discharge the material and the aqueous solution layer is separated as much as possible to obtain a first processed product containing a fat layer and a separated second processed product containing mostly aqueous solution.

[0024] According to the above scheme, after the crayfish processing water is allowed to stand and separate into layers in step S1.1, the gate is opened to discharge most of the aqueous solution in the lower layer until the liquid level of the aqueous solution layer is 4-6 cm, thereby obtaining a first processed product containing a fat layer and a separated second processed product containing most of the aqueous solution.

[0025] The above-mentioned crayfish processing water comes from the steaming and cooling steps in the crayfish processing process, which contains a variety of nutrients such as shrimp roe and water-soluble protein. After initial separation by static stratification, it is first treated with a hanging bag centrifuge carrying a hydrophilic and oleophobic coating. The solid shrimp roe and liquid fatty components can be retained in the hanging bag to obtain a semi-solid filter residue, i.e., crude shrimp roe. The aqueous solution containing water-soluble protein passes through the hanging bag to form a filtrate. The recovered filtrate is combined with the second processed product obtained by the initial separation to extract the water-soluble protein by flocculation.

[0026] The crude shrimp roe is washed with rice water and peracetic acid solution successively. The rice water can remove dirt and heavy metals, while reducing the fishy smell of shrimp roe and improving the flavor. Peracetic acid, as a high-efficiency disinfectant with antibacterial activity, can destroy microbial proteins and enzymes through hydroxyl free radical oxidation, thereby sterilizing the shrimp roe without producing toxic residues.

[0027] According to the above scheme, the hydrophilic oleophobic coating is composited with polydopamine and sodium polyacrylate, and the preparation method is as follows:

[0028] 1) dissolving dopamine in a Tris-HCl buffer solution with a pH of 6.8 to 8.5 to obtain a dopamine solution, and immersing the hanging bag in the dopamine solution for 25 to 40 minutes;

[0029] 2) Add sodium persulfate to the dopamine solution in which the hanging bag is soaked, and continue soaking for 20 to 30 minutes;

[0030] 3) Sodium polyacrylate is added to the solution in which the hanging bag is soaked in step 2) to obtain a mixed solution, the hanging bag continues to be soaked in the mixed solution for 1.5 to 2.5 hours, and then the hanging bag is taken out, cleaned, and dried.

[0031] The hydrophilic and oleophobic coating formed by the composite of polydopamine and sodium polyacrylate has good hydrophilicity and oleophobicity, and polydopamine has good adhesion, which can enhance the adhesion of the hanging bag surface. Sodium persulfate is used as an initiator in the preparation process, which can promote the polymerization reaction of dopamine and the rapid formation of a coating by sodium polyacrylate. It can be used to effectively separate crayfish roe, liquid fatty components and other components, greatly improving the recovery rate of crude roe.

[0032] According to the above scheme, in step 3), after adding sodium polyacrylate, stir at room temperature for 1 to 2 hours, then let it stand and soak for 20 to 40 minutes before taking it out.

[0033] According to the above scheme, the mass concentration of dopamine in the dopamine solution is 0.5% to 4%, the molar concentration of sodium persulfate in the mixed solution is 0.1 to 1 mol / L, and the mass concentration of sodium polyacrylate is 0.1% to 2%.

[0034] According to the above scheme, in step S1.3, the weight ratio of shrimp roe to rice washing water is 1:10-30, the bubbling flow rate is 200-250 L / min, the bubbling cleaning time is 20-35 min, the concentration of peracetic acid solution is 0.3%-1%, the ultrasonic power is 300-500 W, the ultrasonic temperature is 40-50° C., and the ultrasonic time is 20-60 min.

[0035] According to the above scheme, in step S1.3, the deacetylation degree of chitosan is 80% to 99%. Before using chitosan and sodium alginate, chitosan is first dissolved in 0.5wt% to 2wt% acetic acid solution to prepare a chitosan acetic acid solution with a chitosan concentration of 0.5% to 1%, and sodium alginate is dissolved in water to prepare a sodium alginate aqueous solution with a concentration of 0.3% to 0.6%. The added amounts of chitosan and sodium alginate per liter of mixed filtrate are 2.5g to 5g and 1.5g to 3g, respectively.

[0036] A hydrophilic and oleophobic coating is set on the hanging bag, and the recovery efficiency of crude shrimp roe reaches more than 85%. It is double-cleaned with rice washing water and peracetic acid solution. The obtained shrimp roe has no fishy smell, low heavy metal content, high safety, and high overall quality. At the same time, water-soluble proteins can be effectively recovered.

[0037] The beneficial effects of the present invention are:

[0038] 1) The present invention adds water-soluble protein, green salvia extract and mung bean peel extract in the preparation of crayfish roe powder, wherein a composite emulsifier composed of green salvia extract and mung bean peel extract is used to emulsify the oil in the roe, which is helpful for homogenizing and emulsifying the mixed solution to make the material body uniform. The green salvia extract contains 18 kinds of amino acids, vitamins, minerals and other active ingredients, has excellent antioxidant properties, is highly safe, and has a certain effect on extending the storage period of the roe powder; adding mung bean peel extract can add a unique fresh aroma of mung beans, play a role in covering up the fishy smell, can well improve the fragrance of the roe powder, and ensure the nutritional quality of the roe powder. Further, in conjunction with the recovery of water-soluble protein, the water-soluble protein is added to the frozen roe for secondary emulsification. The synergistic effect of the green salvia and mung bean peel extract can not only improve the oxidative stability of the prepared roe powder, but also improve the emulsification activity to a certain extent.

[0039] 2) The present invention utilizes crayfish roe and water-soluble protein recovered from crayfish processing water to prepare crayfish roe powder, which not only avoids the pollution of the crayfish processing water to the environment, but also further increases the added value of crayfish and improves the economic benefits of the enterprise.

[0040] 3) The method is simple and efficient to operate, can effectively remove dirt and reduce the fishy smell of raw materials, and at the same time give the shrimp yellow powder a special fresh aroma, thereby ensuring the color and nutritional quality of the shrimp yellow powder;

[0041] 4) The shrimp yellow powder of the present invention is rich in nutrition, bright and shiny in color, fluffy in texture, and has excellent emulsifying and antioxidant properties, and can be used for the preparation of animal food such as feed. DETAILED DESCRIPTION

[0042] The principles and features of the present invention are described below in conjunction with specific embodiments. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0043] The invention provides a shrimp roe powder, which is obtained by spray-drying and grinding the following raw materials. The raw materials include, by weight: 400-800 parts of recovered crayfish roe, 50-75 parts of recovered water-soluble protein, 12-64 parts of grass green salicornia extract, 2-12 parts of mung bean peel extract, and 800-1600 parts of water. The mass of the grass green salicornia extract is 3%-8% of the mass of the water, and the mass of the mung bean peel extract is 0.5%-1.5% of the mass of the water.

[0044] The present invention also provides a method for preparing the shrimp yellow powder, comprising the following steps:

[0045] S1. The recovered crayfish roe and the recovered water-soluble protein are freeze-dried to obtain freeze-dried crayfish roe and freeze-dried water-soluble protein;

[0046] S2. Adding a green salicornia extract and a mung bean peel extract to ultrapure water, standing to allow both to completely dissolve to obtain a mixed solution, adding freeze-dried crayfish roe to the mixed solution for homogenization and emulsification to make the material state uniform, and then adding freeze-dried water-soluble protein for secondary emulsification to obtain a pre-emulsion, and subjecting the pre-emulsion to ice bath ultrasonic treatment to obtain an emulsion;

[0047] S3. The emulsion is spray dried to obtain a semi-finished shrimp powder;

[0048] S4. Use air classification grinding technology to obtain shrimp roe powder of uniform size.

[0049] In some specific embodiments, the homogenization conditions in step S2 are: rotation speed 6000-10000 rpm, time 5-8 min, and ice bath ultrasonic conditions are: frequency 25-45 Hz, intensity 200-600 W, temperature 0-4° C., time 10 min.

[0050] In some specific embodiments, high-pressure airflow spray drying is used in step S3, and the conditions are: inlet air temperature 130-170°C, outlet air temperature 101-110°C, peristaltic speed 20-24RPM, carrier gas flow rate 10-40L / s, and through a 80-150 mesh sieve.

[0051] The high-pressure combined airflow spray drying technology is used to enhance the friction resistance of the emulsion and steam flow. The hot air flow rate in the airflow spray dryer is high, which can make the droplets fully contact with the hot air, evaporate the water quickly, and promote the atomization of the material in the carrier gas, thereby achieving a faster drying speed.

[0052] In some specific embodiments, low-frequency shaking vacuum freeze drying is used in step S1, and the vacuum degree is 0.05 to 0.1 kPa, and the cold trap temperature is -45 to -80°C. The product is vacuum freeze dried for 24 to 48 hours and then taken out.

[0053] Low-altitude shaking vacuum freeze-drying technology can sublime the ice crystals in the material into gas. Through low-frequency shaking, it can enhance the heat and mass transfer efficiency of the material during the drying process, ensure that the material is fully dried from the inside out, and can maintain the color, aroma, taste, shape and freshness of the material to the greatest extent.

[0054] In some specific embodiments, the conditions for air classification grinding in step S4 are a rotation speed of 4500-5500 r / min, a grinding pressure of 0.6-1.0 MPa, an average particle size of shrimp yellow powder is 14.8 μm, and a particle size range is 10-20 μm.

[0055] The air classification grinding technology is adopted, combining the two processes of crushing and classification. The frequency-controlled classification wheel separates the coarse and fine materials, and circulates the grinding to the target particle size. Air classification can improve the air cleaning efficiency by more than 50%, save energy and reduce emissions, and make the shrimp roe powder fluffy, without obvious agglomeration, and uniform in size. While ensuring the quality of shrimp roe powder, it can also reduce enzyme activity and oxidation loss. Therefore, the air classification grinding technology can better ensure the fiber structure, color and nutrition of shrimp roe powder.

[0056] In some specific embodiments, the crayfish roe and water-soluble protein obtained by using crayfish processing water in step S1 are recovered, and the recovery method comprises the following steps:

[0057] S1.1 The crayfish processing water is allowed to stand for stratification to obtain an upper oil layer containing solid and liquid shrimp roe components, which is a first processed product for recovering shrimp roe, and a lower aqueous solution layer, which is a second processed product for recovering water-soluble protein;

[0058] S1.2 using a hanging bag centrifuge to process the first processed product to obtain a filtrate and a semi-solid filter residue trapped in the hanging bag, recovering the filtrate and the filter residue, wherein the filter residue is a crude shrimp roe product, and the filtrate is incorporated into the second processed product separated in step S1.1 to obtain a mixed filtrate, wherein the hanging bag of the hanging bag centrifuge is provided with a hydrophilic oleophobic coating;

[0059] S1.3 The crude shrimp roe and the mixed filtrate are treated separately: the crude shrimp roe is placed in rice washing water for bubbling washing, filtered using a hanging bag centrifuge equipped with a hydrophilic and oleophobic coating, and then placed in a peracetic acid solution for ultrasonic shaking combined washing, filtered using a hanging bag centrifuge equipped with a hydrophilic and oleophobic coating to obtain recovered crayfish roe; chitosan and sodium alginate are added to the mixed filtrate to flocculate and precipitate the water-soluble protein, and filtered to obtain recovered water-soluble protein.

[0060] In some specific embodiments, after the crayfish processing water is allowed to stand and separate into layers in S1.1, the gate is opened to discharge the material and separate the aqueous solution layer as much as possible to obtain a first processed product including a fat layer and a separated second processed product containing mostly aqueous solution.

[0061] In some specific embodiments, after the crayfish processing water is allowed to stand and separate into layers in step S1.1, the gate is opened to unload the material and most of the aqueous solution in the lower layer is separated as much as possible until the liquid level of the aqueous solution layer is 4-6 cm, thereby obtaining a first processed product containing a fat layer and a separated second processed product containing most of the aqueous solution.

[0062] The crude shrimp roe is washed with rice water and peracetic acid solution successively. The rice water can remove dirt and heavy metals, while reducing the fishy smell of shrimp roe and improving the flavor. Peracetic acid, as a high-efficiency disinfectant with antibacterial activity, can destroy microbial proteins and enzymes through hydroxyl free radical oxidation, thereby sterilizing the shrimp roe without producing toxic residues.

[0063] In some specific embodiments, the hydrophilic oleophobic coating is composited with polydopamine and sodium polyacrylate, and the preparation method is:

[0064] 1) dissolving dopamine in a Tris-HCl buffer solution with a pH of 6.8 to 8.5 to obtain a dopamine solution, and immersing the hanging bag in the dopamine solution for 25 to 40 minutes;

[0065] 2) Add sodium persulfate to the dopamine solution in which the hanging bag is soaked, and continue soaking for 20 to 30 minutes;

[0066] 3) Sodium polyacrylate is added to the solution in which the hanging bag is soaked in step 2) to obtain a mixed solution, the hanging bag continues to be soaked in the mixed solution for 1.5 to 2.5 hours, and then the hanging bag is taken out, cleaned, and dried.

[0067] The hydrophilic and oleophobic coating formed by the composite of polydopamine and sodium polyacrylate has good hydrophilicity and oleophobicity, and polydopamine has good adhesion, which can enhance the adhesion of the hanging bag surface. Sodium persulfate is used as an initiator in the preparation process, which can promote the polymerization reaction of dopamine and the rapid formation of a coating by sodium polyacrylate. It can be used to effectively separate crayfish roe, liquid fatty components and other components, greatly improving the recovery rate of crude roe.

[0068] In some specific embodiments, in step 3), after adding sodium polyacrylate, it is first stirred at room temperature for 1 to 2 hours, and then allowed to stand and soak for 20 to 40 minutes before being taken out.

[0069] In some specific embodiments, the mass concentration of dopamine in the dopamine solution is 0.5% to 4%, the molar concentration of sodium persulfate in the mixed solution is 0.1 to 1 mol / L, and the mass concentration of sodium polyacrylate is 0.1% to 2%.

[0070] In some specific embodiments, in step S1.3, the weight ratio of shrimp roe to rice washing water is 1:10-30, the bubbling flow rate is 200-250 L / min, the bubbling cleaning time is 20-35 min, the concentration of peracetic acid solution is 0.3%-1%, the ultrasonic power is 300-500 W, the ultrasonic temperature is 40-50° C., and the ultrasonic time is 20-60 min.

[0071] In some specific embodiments, in step S1.3, the deacetylation degree of the chitosan is 80% to 99%. Before using chitosan and sodium alginate, the chitosan is first dissolved in 0.5wt% to 2wt% acetic acid solution to prepare a chitosan acetic acid solution with a chitosan concentration of 0.5% to 1%, and the sodium alginate is dissolved in water to prepare a sodium alginate aqueous solution with a concentration of 0.3% to 0.6%. The amount of chitosan and sodium alginate added to each liter of the mixed filtrate is 2.5g to 5g and 1.5g to 3g, respectively.

[0072] A hydrophilic and oleophobic coating is set on the hanging bag, and the recovery efficiency of crude shrimp roe reaches more than 85%. It is double-cleaned with rice washing water and peracetic acid solution. The obtained shrimp roe has no fishy smell, low heavy metal content, high safety, and high overall quality. At the same time, water-soluble proteins can be effectively recovered.

[0073] The following are specific embodiments.

[0074] Embodiment 1 A kind of preparation method of shrimp yellow powder

[0075] The recovered crayfish roe and recovered water-soluble protein used in the preparation of the shrimp roe powder in this embodiment are derived from the crayfish processing water generated during the crayfish cooking and cooling process.

[0076] (1) Preparation of hydrophilic and oleophobic hanging bags: Weigh 5 g of dopamine and dissolve it in a 10 mM Tris-HCl buffer solution with a pH of 8.5 to prepare a dopamine solution with a mass concentration of 0.5%. Soak the hanging bag in the solution for 30 minutes, then add sodium persulfate to make the concentration of sodium persulfate in the solution 0.1 mol / L, and continue soaking for 30 minutes. Then weigh sodium polyacrylate and add it to the solution to make the mass concentration of sodium polyacrylate in the solution 0.3%, stir at room temperature for 2 hours, let it stand for 30 minutes, then take out the hanging bag, wash it with clean water and ethanol respectively, and dry it at 50°C to obtain a hydrophilic and oleophobic hanging bag.

[0077] (2) Initial separation: First, the crayfish processing water is discharged by opening the valve to separate a portion of the lower aqueous solution and inject it into the hanging bag centrifuge (without the hanging bag at this time), and the liquid level of the aqueous solution layer is 5 cm, and then the separation is stopped to obtain a first processed product containing a fat layer and a separated second processed product containing most of the aqueous solution;

[0078] (3) Recovery of shrimp roe and water-soluble protein: The first processed product is poured into a bag centrifuge equipped with the above-mentioned hydrophilic and oleophobic bag at a speed of 1500 r / min to obtain a filtrate and a filter residue trapped in the hydrophilic and oleophobic bag, wherein the filter residue is a crude shrimp roe product and is recovered for later use; the filtrate is added to the second processed product obtained by the initial separation to obtain a mixed filtrate, and chitosan-sodium alginate is added to the mixed filtrate at a feed rate of 4 g / L, wherein the mass ratio of chitosan to sodium alginate is 5:3, wherein: chitosan is dissolved in 500 mL of 2% acetic acid solution to prepare a chitosan acetic acid solution in advance, and sodium alginate is dissolved in deionized water to prepare a sodium alginate aqueous solution in advance, and the chitosan acetic acid solution and the sodium alginate aqueous solution are mixed and set aside; the water-soluble protein is flocculated, allowed to stand for 30 min, filtered, and the recovered water-soluble protein is placed in a -80°C refrigerator for later use.

[0079] (4) Recovering the shrimp roe, cleaning and processing: soaking the crayfish roe recovered in step (3) in rice washing water for bubbling cleaning, wherein the weight ratio of the shrimp roe to the rice washing water is 1:10 (m:m), the bubbling flow rate is 220 L / min, the bubbling cleaning time is 30 min, filtering in a hanging bag centrifuge equipped with a hydrophilic and oleophobic hanging bag, then placing in a 0.3% peracetic acid solution for ultrasonic and oscillation combined cleaning for 20 min, filtering in a hanging bag centrifuge equipped with a hydrophilic and oleophobic hanging bag, obtaining the recovered crayfish roe, and placing in a -80°C refrigerator for freezing for standby use;

[0080] (5) Drying: The water-soluble protein recovered in step (3) and the crayfish roe after washing in step (4) are pre-frozen in a -80°C refrigerator for more than 12 hours, and then placed in a low-frequency shaking vacuum freeze-drying chamber, under the conditions of a vacuum degree of 0.1 kPa and a cold trap temperature of -45°C, and vacuum freeze-dried for 24 hours to obtain freeze-dried crayfish roe and freeze-dried water-soluble protein;

[0081] (6) Emulsification: add 12 g of Salicornia herba extract and 2 g of Mung Bean peel extract to 400 ml of ultrapure water, let the mixed solution stand at 37° C. for 2 h, then add 400 g of the freeze-dried crayfish roe of step (5), mix and homogenize until the material is uniform, then add 50 g of the freeze-dried water-soluble protein of step (5) for a second emulsification to obtain a pre-emulsion, the homogenization conditions are 6000 rpm, 5 min, ultrasonic frequency of 35 Hz, ultrasonic intensity of 200 W, temperature of 0° C., and ultrasonication for 10 min;

[0082] (7) Powder making: The emulsion of step (6) is subjected to high-pressure airflow spray drying to separate the powder or fine particles, which are passed through an 80-mesh sieve. Spray drying conditions: inlet air temperature 150°C, outlet air temperature 101°C, creep speed 22.0RPM, carrier gas flow rate 10L / s;

[0083] (8) Grinding: The powder obtained in step (7) is subjected to air classification grinding technology to remove larger particles and obtain shrimp roe powder with a particle size of 10 to 20 μm. The rotation speed is 5500 r / min and the grinding pressure is 0.6 MPa to obtain fine powder with an average particle size of about 14.8 μm.

[0084] Embodiment 2, same as embodiment 1, except that:

[0085] (1) Preparation of hydrophilic and oleophobic hanging bags: Weigh 5 g of dopamine and dissolve it in a 10 mM Tris-HCl buffer solution with a pH of 8.5 to prepare a dopamine solution with a mass concentration of 0.5%. Soak the hanging bag in the solution for 30 minutes, then add sodium persulfate to make the concentration of sodium persulfate in the solution 0.1 mol / L, and continue soaking for 30 minutes. Then weigh sodium polyacrylate and add it to the solution to make the mass concentration of sodium polyacrylate in the solution 0.3%, stir at room temperature for 2 hours, let it stand for 30 minutes, then take out the hanging bag, wash it with clean water and ethanol respectively, and dry it at 50°C to obtain a hydrophilic and oleophobic hanging bag.

[0086] (2) Initial separation: First, the crayfish processing water is discharged by opening the valve to separate a portion of the lower aqueous solution and inject it into the hanging bag centrifuge (without the hanging bag at this time), and the liquid level of the aqueous solution layer is 5 cm, and then the separation is stopped to obtain a first processed product containing a fat layer and a separated second processed product containing most of the aqueous solution;

[0087] (3) Recovery of shrimp roe and water-soluble protein: The first processed product is poured into a hanging bag centrifuge in which the above-mentioned hydrophilic and oleophobic hanging bag is placed, and the rotation speed is 1500r / min to obtain a filtrate and a filter residue trapped in the hydrophilic and oleophobic hanging bag, wherein the filter residue is a crude shrimp roe product and is recovered for later use; the filtrate is merged into the second processed product obtained by the initial separation to obtain a mixed filtrate, and chitosan-sodium alginate is added to the mixed filtrate at a feed rate of 5g / L, and the mass ratio of chitosan to sodium alginate is 5:3, wherein: chitosan is dissolved in 500mL of 2% acetic acid solution to prepare a chitosan acetic acid solution in advance, and sodium alginate is dissolved in 500mL of deionized water to prepare a sodium alginate aqueous solution in advance, and the chitosan acetic acid solution and the sodium alginate aqueous solution are mixed and set aside, and the water-soluble protein is flocculated, left to stand for 30min, and filtered to obtain recovered water-soluble protein, which is placed in a -80°C refrigerator for later use.

[0088] (4) Recovering the shrimp roe, cleaning and processing: soaking the crayfish roe recovered in step (3) in rice washing water for bubbling cleaning, wherein the weight ratio of shrimp roe to rice washing water during the cleaning process is 1:15 (m:m), the bubbling flow rate is 225 L / min, the bubbling cleaning time is 30 min, filtering in a hanging bag centrifuge equipped with a hydrophilic and oleophobic hanging bag, then placing in a hanging bag centrifuge equipped with a 0.5% peracetic acid solution for ultrasonic and oscillation combined cleaning for 40 min, filtering in a hanging bag centrifuge equipped with a hydrophilic and oleophobic hanging bag, obtaining recovered crayfish roe, and placing in a -80°C refrigerator for freezing for standby use;

[0089] (5) Drying: The water-soluble protein recovered in step (3) and the crayfish roe after washing in step (4) are pre-frozen in a -80°C refrigerator for more than 12 hours, and then placed in a low-frequency shaking vacuum freeze-drying chamber, under the conditions of a vacuum degree of 0.1 kPa and a cold trap temperature of -45°C, and vacuum freeze-dried for 48 hours to obtain freeze-dried crayfish roe and freeze-dried water-soluble protein;

[0090] (6) Emulsification: add 20 g of Salicornia herba extract and 3.2 g of Mung Bean peel extract to 400 ml of ultrapure water, let the mixed solution stand at 37° C. for 2 h, then add 600 g of the freeze-dried crayfish roe of step (5), mix and homogenize until the material is uniform, then add 60 g of the freeze-dried water-soluble protein of step (5) for a second emulsification to obtain a pre-emulsion, the homogenization conditions are 6000 rpm, 5 min, ultrasonic frequency of 35 Hz, ultrasonic intensity of 200 W, temperature of 4° C., and ultrasonication for 10 min;

[0091] (7) Powder making: The emulsion of step (6) is subjected to high-pressure airflow spray drying to separate the powder or fine particles, which are passed through a 100-mesh sieve. Spray drying conditions: inlet air temperature 150°C, outlet air temperature 101°C, creep speed 22.0RPM, carrier gas flow rate 20L / s;

[0092] (8) Grinding: The powder obtained in step (7) is subjected to air classification grinding technology to remove larger particles and obtain shrimp roe powder with a particle size of 10 to 20 μm. The rotation speed is 5500 r / min and the grinding pressure is 0.6 MPa.

[0093] Embodiment 3 is different from Embodiment 1 in that:

[0094] (3) Recovery of shrimp roe and water-soluble protein: The first processed product is poured into a hanging bag centrifuge in which the above-mentioned hydrophilic and oleophobic hanging bag is placed, and the rotation speed is 1500r / min to obtain a filtrate and a filter residue trapped in the hydrophilic and oleophobic hanging bag, wherein the filter residue is a crude shrimp roe product and is recovered for later use; the filtrate is merged into the second processed product obtained by the initial separation to obtain a mixed filtrate, and chitosan-sodium alginate is added to the mixed filtrate at a feed rate of 4g / L, and the mass ratio of chitosan to sodium alginate is 5:3, wherein: chitosan is dissolved in 500mL of 2% acetic acid solution to prepare a chitosan acetic acid solution in advance, and sodium alginate is dissolved in 500mL of deionized water to prepare a sodium alginate aqueous solution in advance, and the chitosan acetic acid solution and the sodium alginate aqueous solution are mixed and set aside, and the water-soluble protein is flocculated, left to stand for 30min, and filtered to obtain recovered water-soluble protein, which is placed in a -80°C refrigerator for later use.

[0095] (4) Recovering the shrimp roe, cleaning and processing: soaking the crayfish roe recovered in step (3) in rice washing water for bubbling cleaning, wherein the weight ratio of the shrimp roe to the rice washing water during the cleaning process is 1:20 (m:m), the bubbling flow rate is 250 L / min, the bubbling cleaning time is 30 min, filtering in a hanging bag centrifuge equipped with a hydrophilic and oleophobic hanging bag, then placing in a 0.8% peracetic acid solution for ultrasonic and oscillation combined cleaning for 60 min, filtering in a hanging bag centrifuge equipped with a hydrophilic and oleophobic hanging bag, obtaining the recovered crayfish roe, and placing in a -80°C refrigerator for freezing for standby use;

[0096] (5) Drying: pre-freeze the water-soluble protein recovered in step (3) and the crayfish roe after washing in step (4) in a -80°C refrigerator for more than 12 hours, and then place them in a low-frequency shaking vacuum freeze-drying chamber, under the conditions of a vacuum degree of 0.1 kPa and a cold trap temperature of -45°C, and vacuum freeze-dry for 48 hours to obtain freeze-dried crayfish roe and freeze-dried water-soluble protein;

[0097] (6) Emulsification: add 32 g of Salicornia herba extract and 4.8 g of Mung Bean peel extract to 400 ml of ultrapure water, let the mixed solution stand at 37° C. for 2 h, then add 800 g of the freeze-dried crayfish roe of step (5), mix and homogenize until the material is uniform, then add 75 g of the freeze-dried water-soluble protein of step (5) for a second emulsification to obtain a pre-emulsion, the homogenization conditions are 6000 rpm, 8 min, ultrasonic frequency of 35 Hz, ultrasonic intensity of 200 W, temperature of 4° C., and ultrasonication for 10 min;

[0098] (7) Powder making: The emulsion of step (6) is subjected to high-pressure airflow spray drying to separate the powder or fine particles, which are passed through a 120-mesh sieve. Spray drying conditions: inlet air temperature 150°C, outlet air temperature 101°C, creep speed 22.0RPM, carrier gas flow rate 30L / s;

[0099] (8) Grinding: The powder obtained in step (7) is subjected to air classification grinding technology to remove larger particles and obtain shrimp roe powder with a particle size of 10 to 20 μm. The rotation speed is 5500 r / min and the grinding pressure is 0.6 MPa.

[0100] Comparative Example 1 is different from Example 1 in that:

[0101] (4) Cleaning and processing of unrecovered shrimp roe: soak the crayfish roe recovered in step (3) in ultrapure water at a weight ratio of 1:10 (m:m) for 30 min, filter, and freeze in a -80°C refrigerator for later use;

[0102] Comparative Example 2 is different from Example 1 in that:

[0103] (5) Oven drying: Take out the water-soluble protein recovered in step (3) and the crayfish roe after cleaning in step (4), put them into a constant temperature drying oven at a temperature of 105° C., and dry them for 5 to 6 hours;

[0104] Comparative Example 3 is different from Example 1 in that:

[0105] (6) Without adding Salicornia herba extract and Mung Bean peel extract, ultrasonic stirring emulsification was directly performed: freeze-dried crayfish roe and freeze-dried water-soluble protein in step (5) were added to 400 ml of ultrapure water, homogenized, and the mixed solution was allowed to stand at 37° C. for 2 h, and then subjected to ice bath ultrasonic treatment. The homogenization conditions were 6000 rpm, 5 min, ultrasonic frequency of 35 Hz, ultrasonic intensity of 200 W, temperature of 4° C., and ultrasonication for 10 min.

[0106] Comparative Example 4 is different from Example 1 in that:

[0107] (7) Airflow-free spray drying: spray-dry the emulsion from step (6) to separate the powder or fine particles, and pass through an 80-mesh sieve. Spray drying conditions: inlet air temperature 150°C, outlet air temperature 101°C, creeping speed 22.0RPM;

[0108] Comparative Example 5 is different from Example 1 in that:

[0109] There is no step (8) grinding.

[0110] The performance of the recovered crayfish roe and the recovered water-soluble protein obtained in the preparation process of Examples 1-3 was characterized, wherein:

[0111] The test method for the crude shrimp roe yield is as follows: crude shrimp roe yield = (weight of crude shrimp roe / weight of first processed product) * 100%

[0112] The recovery test method of water-soluble protein is as follows:

[0113] Water-soluble protein recovery rate = (1-water-soluble protein mass concentration in the supernatant obtained after flocculation / protein mass concentration in the mixed filtrate before flocculation) * 100%

[0114] Water-soluble protein content = (mass of water-soluble protein in recovered water-soluble protein / mass of recovered water-soluble protein) * 100%

[0115] The results are shown in Table 1 below

[0116] Table 1

[0117]

[0118]

[0119] For the shrimp yellow powder prepared by Comparative Examples 1 to 3 and Comparative Examples 1 to 5, the sensory evaluation standards are shown in Table 2, the sensory evaluation is shown in Table 3, the chroma and quality are shown in Table 4, the emulsification activity and emulsification stability are shown in Table 5, and the lipid oxidation changes are shown in Table 6.

[0120] Table 2 Sensory evaluation standard of shrimp yellow powder

[0121]

[0122] Table 3 Sensory evaluation of shrimp yellow powder

[0123] Sample Source Color and Odor Appearance Sensory score (points)

[0124]

[0125] Table 4 Shrimp yellow pink color and quality

[0126]

[0127] Table 5 Emulsifying activity and emulsification stability in emulsion

[0128]

[0129] Table 6 Changes in lipid oxidation of shrimp yellow powder

[0130]

[0131] It can be seen from the results in Table 3 that washing with rice water combined with peracetic acid can effectively reduce the strong fishy smell of shrimp, and increasing the airflow for spray drying can make the shrimp yellow powder bulky and not agglomerate. In Comparative Example 3, no emulsifier was added, so the solution was uneven and droplets could not be formed during spray drying. In Comparative Example 5, no grinding was performed, resulting in agglomeration, which affected its sensory perception.

[0132] It can be seen from the results of Examples 1 to 3 in Table 5 that the appropriate addition of an emulsifier can improve the quality of the powder oil and avoid the occurrence of agglomeration and the like; in Comparative Example 2, the shrimp roe liposomes were destroyed under high temperature drying conditions, and in Comparative Example 3, no emulsifier (green salvia extract and mung bean peel extract) was added, and only ultrasonic stirring emulsification failed to completely emulsify the shrimp roe, which resulted in a decrease in the astaxanthin content in the prepared shrimp roe powder, and appropriate drying temperature and emulsification time made the shrimp roe powder have a better color, and the powder was more fluffy after high-pressure airflow spray drying. The use of green salvia extract and mung bean peel extract The peel extract better guarantees its original nutritional quality, and also covers the fishy smell of shrimp yellow itself in the sense organ; As can be seen from the control results of Table 6, the rice washing water is combined with peracetic acid cleaning, adding grass green salt horn grass extract and mung bean peel extract emulsifier, high-pressure airflow spray drying and air classification milling technology, these steps play an important role in the processing process of recovering shrimp yellow, so that the shrimp yellow powder is reduced in oxidation degree during storage, the antioxidant activity of the shrimp yellow powder is increased, the oxidation of phospholipids and triglycerides is suppressed, and the lipid oxidation level is delayed, so that the shelf life can be extended. Therefore, the present invention adopts the recovery of crayfish shrimp yellow powder after the rice washing water combined with peracetic acid cleaning treatment, low-frequency shaking vacuum freeze drying, natural extract emulsifier, high-pressure airflow spray drying technology powder making and air classification milling technology grinding, while improving the bulkiness of the shrimp yellow powder and reducing the fishy smell, the nutritional characteristics of the shrimp yellow powder are guaranteed.

[0133] The shrimp yellow powder prepared by the invention is rich in nutrition, bright and shiny in color, fluffy in texture, and excellent in emulsification and antioxidant properties, and can be used for the preparation of animal food such as feed.

[0134] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A shrimp yellow powder, characterized in that: The invention is obtained by spray drying and grinding the following raw materials, which include, by weight: 400-800 parts of recovered crayfish roe, 50-75 parts of recovered water-soluble protein, 12-64 parts of green salicornia extract, 2-12 parts of mung bean peel extract, and 800-1600 parts of water, wherein the mass of the green salicornia extract is 3%-8% of the mass of water, and the mass of the mung bean peel extract is 0.5%-1.5% of the mass of water.

2. The method for preparing shrimp yellow powder according to claim 1, characterized in that: The steps include: S1. The recovered crayfish roe and the recovered water-soluble protein are freeze-dried to obtain freeze-dried crayfish roe and freeze-dried water-soluble protein; S2. Adding a green salicornia extract and a mung bean peel extract to ultrapure water, standing to allow both to completely dissolve to obtain a mixed solution, adding freeze-dried crayfish roe to the mixed solution for homogenization and emulsification to make the material state uniform, and then adding freeze-dried water-soluble protein for secondary emulsification to obtain a pre-emulsion, and subjecting the pre-emulsion to ice bath ultrasonic treatment to obtain an emulsion; S3. The emulsion is spray dried to obtain a semi-finished shrimp powder; S4. Use air classification grinding technology to obtain shrimp roe powder of uniform size.

3. The method for preparing shrimp yellow powder according to claim 2, characterized in that: The homogenization conditions in step S2 are: rotation speed 6000-10000 rpm, time 5-8 min, and ice bath ultrasonic conditions are: frequency 25-45 Hz, intensity 200-600 W, temperature 0-4° C., time 10 min.

4. The method for preparing shrimp yellow powder according to claim 2, characterized in that: In step S3, air flow spray drying is adopted, and the conditions are: inlet air temperature 130-170°C, outlet air temperature 101-110°C, creeping speed 20-24RPM, carrier gas flow rate 10-40L / s, and passing through a sieve of 80-150 mesh.

5. The method for preparing shrimp yellow powder according to claim 4, characterized in that: The conditions for air classification grinding in step S4 are a rotation speed of 4500-5500 r / min, a grinding pressure of 0.6-1.0 MPa, and a particle size range of shrimp yellow powder is 10-20 μm.

6. The method for preparing shrimp roe powder according to any one of claims 2 to 5, characterized in that: In step S1, the crayfish roe and water-soluble protein are recovered using the crayfish processing water, and the recovery method comprises the following steps: S1.1 The crayfish processing water is allowed to stand for stratification, and the upper oil layer containing solid and liquid shrimp roe components is initially separated to obtain a first processed product for recovering shrimp roe, and the lower aqueous solution layer is a second processed product for recovering water-soluble protein; S1.2 using a hanging bag centrifuge to process the first processed product to obtain a filtrate and a semi-solid filter residue trapped in the hanging bag, recovering the filtrate and the filter residue, wherein the filter residue is a crude shrimp roe product, and the filtrate is incorporated into the second processed product separated in step S1.1 to obtain a mixed filtrate, wherein the hanging bag of the hanging bag centrifuge is provided with a hydrophilic oleophobic coating; S1.3 The crude shrimp roe and the mixed filtrate are treated separately: the crude shrimp roe is placed in rice washing water for bubbling washing, filtered using a hanging bag centrifuge equipped with a hydrophilic and oleophobic coating, and then placed in a peracetic acid solution for ultrasonic shaking combined washing, filtered using a hanging bag centrifuge equipped with a hydrophilic and oleophobic coating to obtain recovered crayfish roe; chitosan and sodium alginate are added to the mixed filtrate to flocculate and precipitate the water-soluble protein, and filtered to obtain recovered water-soluble protein.

7. The method for preparing shrimp yellow powder according to claim 6, characterized in that: The hydrophilic oleophobic coating is composited with polydopamine and sodium polyacrylate, and the preparation method is as follows: 1) dissolving dopamine in a Tris-HCl buffer solution with a pH of 6.8 to 8.5 to obtain a dopamine solution, and immersing the hanging bag in the dopamine solution for 25 to 40 minutes; 2) Add sodium persulfate to the dopamine solution in which the hanging bag is soaked, and continue soaking for 20 to 30 minutes; 3) Sodium polyacrylate is added to the solution in which the hanging bag is soaked in step 2) to obtain a mixed solution, the hanging bag continues to be soaked in the mixed solution for 1.5 to 2.5 hours, and then the hanging bag is taken out, cleaned, and dried.

8. The method for preparing shrimp yellow powder according to claim 7, characterized in that: The mass concentration of dopamine in the dopamine solution is 0.5% to 4%, the molar concentration of sodium persulfate in the mixed solution is 0.1 to 1 mol / L, and the mass concentration of sodium polyacrylate is 0.1% to 2%.

9. The method for preparing shrimp yellow powder according to claim 6, characterized in that: In step S1.3, the weight ratio of shrimp roe to rice washing water is 1:10-30, the bubbling flow rate is 200-250 L / min, the bubbling cleaning time is 20-35 min, the concentration of peracetic acid solution is 0.3%-1%, the ultrasonic power is 300-500 W, the ultrasonic temperature is 40-50° C., and the ultrasonic time is 20-60 min.

10. The method for preparing shrimp yellow powder according to claim 6, characterized in that: In step S1.3, the deacetylation degree of the chitosan is 80% to 99%. Before using chitosan and sodium alginate, chitosan is dissolved in 0.5wt% to 2wt% acetic acid solution to prepare a chitosan acetic acid solution with a chitosan concentration of 0.5% to 1%, and sodium alginate is dissolved in water to prepare a sodium alginate aqueous solution with a concentration of 0.3% to 0.6%. The added amounts of chitosan and sodium alginate per liter of mixed filtrate are 2.5g to 5g and 1.5g to 3g, respectively.

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