CN105063153A - Preparation method of food-grade low-salt-content sea fish oligopeptide powder - Google Patents

Abstract

This invention provides a method for preparing food-grade low-salt marine fish oligopeptide powder. Using food-grade low-fat marine fish meal as raw material, the method involves water washing and pre-desalination, colloid milling and pulverization, enzymatic hydrolysis, membrane separation, concentration, and spray drying. This invention pre-desalinates the raw fish meal by water washing, removing most of the salt content and reducing the pressure on subsequent nanofiltration membrane desalination. Enzymatic hydrolysis is performed using food-grade industrial protease preparations. The hydrolysate is separated using a 1000–10000 Da ultrafiltration membrane to remove larger molecular weight pigments and peptides. Then, a 150–500 Da nanofiltration membrane is used to remove free amino acids and residual salt from the hydrolysate. The resulting food-grade low-salt marine fish oligopeptide powder has a high oligopeptide content and low salt content, making it widely applicable in the food industry and suitable for large-scale industrial production.

Description

A kind of preparation method of food-grade low-salt marine fish oligopeptide powder

technical field

This patent belongs to the field of preparation of marine fish active peptides, and specifically relates to the preparation of food-grade low-salt marine fish oligopeptides with molecular weight less than or equal to 1000Da.

Background technique

Oligopeptide refers to a class of functional biologically active peptides consisting of 2 to 10 amino acids and a molecular weight of 180 to 1000 Da. Studies have shown that oligopeptides have strong biological activities, including: regulating hormone levels in the body; improving mineral and trace element absorption; resisting bacteria and viruses; improving immunity; inhibiting and destroying tumor cells; anti-oxidation and scavenging free radicals, etc.

my country has a vast sea area and abundant marine fish resources. With the rapid development of the marine fishing industry, the output of low-value fish caught is on the rise, accounting for about 60% of the marine fishing output. Due to the rich protein content, low-value fish are mainly processed into fish meal as a feed protein additive, which results in the loss of a large amount of protein resources and low economic benefits. If the marine low-value fish meal is further processed to produce marine fish oligopeptides, it can not only effectively improve the utilization of marine low-value fish protein resources, but also increase the added value of the product and achieve a substantial increase in economic benefits.

Usually, the salt content of marine fish meal is 2-5%. Adjusting the pH value during the enzymatic hydrolysis process will bring in some salt. 25%, while purely relying on membrane separation to desalinate is not effective, and the energy consumption is high and the cost is high. The main purpose of the present invention is to overcome the deficiencies of the prior art, propose a method of washing the binding membrane to separate the desalination, use high-quality protease preparations for enzymolysis, and prepare food-grade low-salt marine fish oligopeptide powder, which is large-scale industrialization Production lays a solid foundation.

Contents of the invention

The invention uses a food-grade industrialized protease preparation to hydrolyze food-grade marine low-fat fish meal made from marine low-value fish, thereby obtaining food-grade low-salt marine fish oligopeptide powder. The preparation method involved in the invention comprises the steps of water washing, pre-desalting, colloid mill grinding, enzymolysis, membrane separation, concentration, spray drying and the like. Specific steps are as follows:

(1) Washing and pre-desalination, that is, add food-grade marine low-fat fishmeal and pure water into the pre-desalination mixing tank according to the mass ratio of feed to water 1:2-15, set the temperature at 5-50°C, and stir at a speed of 40-100r/min. Wash with water for 5-60 minutes, and then filter through a 40-200-mesh diaphragm filter press to obtain pre-desalted fish meal.

(2) Grinding and pulverizing by colloid mill, that is, conveying the pre-desalted fish meal to the enzymolysis pre-mixing tank through the screw conveyor, and injecting pure water according to the mass ratio of material to water of 1:4-15, stirring and mixing, and then pumping in through the screw pump Colloid mill, use the colloid mill to grind the pre-desalted fish meal particles to 40-80 mesh, increase the surface area of the fish meal particles, and facilitate contact with enzymes.

(3) Enzymolysis, adjust the pH value to 6.0-10.0, add protease, control the mass ratio of protease to substrate to 0.1-5%, enzymolysis at 40-65°C for 3-6 hours; 99°C, inactivate the enzyme for 10-25 minutes; after cooling, carry out a pressure filter and a second filter to remove slag through a 40-200-mesh diaphragm filter press and a 100-400-mesh bag filter respectively to obtain an enzymatic solution.

(4) Membrane separation, that is, first use the first 1000-10000Da ultrafiltration membrane to intercept the macromolecular peptides and pigments in the enzymatic hydrolysis solution, and then use the second 150-500Da nanofiltration membrane to separate and remove the membrane permeate Free amino acids and residual salts to obtain oligopeptide liquid with molecular weight less than or equal to 1000Da, the separation temperature is 20-60°C, the pressure is 0.4-1.2MPa, and the time is 30-180min.

(5) Concentration and spray drying, that is, first use a three-effect external circulation vacuum concentrator to concentrate the solid content of the oligopeptide solution to 10-30%, and then use a spray drying tower to control the inlet air temperature at 160-200°C. The wind temperature is 80-100°C, and the oligopeptide liquid is dried to obtain food-grade low-salt marine fish oligopeptide powder. The color is light yellow or white, and the yield is 10-35%. The oligopeptide content is ≥85%. The proportion of protein hydrolyzate with a relative molecular mass less than 1000Da is ≥90%, the salt content is ≤4%, the water content is ≤6%, and the ash content is ≤5%.

As a preferred solution of the method for preparing food-grade low-salt marine fish oligopeptide powder of the present invention, wherein: in the step (1), the crude protein content of food-grade marine low-fat fish meal is preferably 70-75%, and the moisture content is ≤8.0 %, crude fat ≤ 2.5%, high protein content, low fat and good enzymatic hydrolysis effect. Preferably, the mass ratio of material to water is 1:10, the temperature is 50°C, the stirring speed is 100r/min, and the water is washed for 30 minutes to remove the salt in the raw fish meal as much as possible.

As a preferred solution of the method for preparing food-grade low-salt marine fish oligopeptide powder in the present invention, wherein: in the step (2), the mass ratio of material to water is preferably 1:6, and the time is 20 minutes, and the pre-desalted fish meal particles are ground Crush to 80 mesh to increase the surface area of the fishmeal particles in contact with the enzyme.

As a preferred version of the method for preparing food-grade low-salt marine fish oligopeptide powder in the present invention, wherein: in the step (3), the preferred protease is a mixture of alkaline protease and neutral protease, and the alkaline protease is such as NS37071 (Denmark Novozymes), neutral protease such as Neutrase0.8L (Danish Novozymes), the amount of both proteases added is 1% of the substrate mass, the optimum pH values are 8.5 and 7.5, and the temperature is 55 ℃, enzymatic hydrolysis time 5h. This condition is favorable for the full hydrolysis of fishmeal protein by alkaline protease and neutral protease.

As a preferred solution of the preparation method of food-grade low-salt marine fish oligopeptide powder in the present invention, wherein: in the step (4), the ultrafiltration membrane with a molecular weight cut-off of 10000Da is preferred for separation, the separation temperature is 45°C, and the pressure is 1.2MPa , time 40min, removal of macromolecular proteins above 10,000Da, large flux, high separation efficiency, avoiding the peptide liquid being polluted by microorganisms and smelly due to too long separation time. Preferably, the nanofiltration membrane with a molecular weight cut-off of 150Da removes free amino acids and residual salts. The separation temperature is 40°C, the pressure is 0.8 MPa, and the time is 60 minutes.

As a preferred solution of the method for preparing the food-grade low-salt marine fish oligopeptide powder of the present invention, in the step (5), the solid content of the oligopeptide liquid is preferably concentrated to 30%, which is convenient for spray drying. The preferred air inlet and outlet temperatures are 180°C and 90°C respectively, so as to minimize the moisture content of the peptide powder and facilitate storage.

The advantages of the present invention are: 1) Wash and pre-desalt the fish meal raw material, remove most of the salt in the raw fish meal, and reduce the pressure of subsequent membrane separation and desalination; 3) Advanced membrane separation technology is used to refine the enzymatic hydrolysis solution to improve the quality of oligopeptides.

The invention makes full use of the abundant low-value fish resources in my country's sea areas, and the prepared peptide powder has high content of oligopeptides and less salt content, can be widely used in the food industry, is suitable for large-scale industrialized continuous production, and is the first choice for my country's marine low-value fish protein Development and utilization have opened up new avenues.

Detailed ways

The present invention can be better understood from the following examples. However, those skilled in the art can easily understand that the content described in the embodiments is only for illustrating the present invention, and should not and will not limit the present invention described in the claims.

Example 1

Food-grade marine low-fat fishmeal is accurately weighed by a measuring scale, mixed with pure water in a pre-desalination mixing tank according to the mass ratio of material to water at 1:5, set the temperature at 25°C, stirred at a speed of 60r/min, washed with water for 10min, and passed through 100 mesh The pre-desalted fish meal is obtained by pressure filtration with a diaphragm filter press, and the desalination rate is 86.2%. The pre-desalted fish meal is transported to the enzymatic hydrolysis pre-mixing tank through a screw conveyor, and pure water is injected according to the mass ratio of material to water at 1:8, and stirred at 60r/min After mixing, pump it into the colloid mill through the screw pump, use the colloid mill to grind the pre-desalted fish meal particles to 60 mesh, and then transport it to the enzymolysis tank through the screw pump to prepare for enzymolysis; control the temperature at 50°C and pH 9.0, according to the base Add Novozymes alkaline protease NS37071 to 0.5% of the substance amount, and after enzymatic hydrolysis for 4 hours, transport it to an enzyme inactivator through a screw pump and heat it up to 90°C to inactivate the enzyme for 20 minutes. Deslagging with a 200-mesh bag filter to obtain the deslagging enzymatic solution; the deslagging enzymatic solution enters the membrane separation system after being sterilized by a pasteurizer, and first uses a membrane separator with a molecular weight cut-off of 5000Da to treat the enzyme Separation of solution, separation pressure 0.6MPa, temperature 40°C, time 1.5h, permeate liquid and then use a membrane separator with a molecular weight cut-off of 300Da to separate, separation pressure 0.8MPa, temperature 30°C, time 2h, to obtain oligopeptide liquid The oligopeptide liquid is concentrated to a solid content of 15% by a three-effect external circulation vacuum concentrator and then spray-dried. The drying conditions are an inlet temperature of 165°C and an outlet temperature of 85°C to obtain food-grade low-salt marine fish oligopeptide powder.

After measurement, the food-grade low-salt marine fish oligopeptide powder prepared in this example has a yield of 20.74%, an oligopeptide content of 86.25%, a protein hydrolyzate below 1000Da of 90.30%, a salt content of 3.44%, a moisture content of 5.78%, and an ash content of 4.26%.

Example 2

Food-grade marine low-fat fish meal is accurately weighed by a measuring scale, mixed with pure water in a pre-desalination mixing tank according to the mass ratio of material to water 1:6, set the temperature at 30°C, and the stirring speed is 60r/min, washed with water for 20min, and then passed through 100 mesh Pre-desalted fish meal is obtained by pressure filtration with a diaphragm filter press, and the desalination rate is 89.8%; the pre-desalted fish meal is transported to the enzymatic hydrolysis pre-mixing tank through a screw conveyor, and pure water is injected according to the mass ratio of material to water at 1:10, and stirred at 60r/min After mixing, it is pumped into the colloid mill through the screw pump, and the pre-desalted fish meal particles are ground and pulverized to 80 mesh by the colloid mill, and then transported to the enzymolysis tank through the screw pump to prepare for enzymolysis; Add 0.8L of Novozymes neutral protease Neutrase to 0.8% of the amount of the substance, and after 6 hours of enzymolysis, transport it to an enzyme inactivator through a screw pump and heat it up to 95°C to inactivate the enzyme for 15 minutes. Filter and 200-mesh bag filter for deslagging to obtain slag-removing enzymatic solution; the slag-removing enzymatic solution is sterilized by a pasteurizer and then enters the membrane separation system, first using a membrane separator with a molecular weight cut-off of 3500Da Separation of the enzymolysis solution, separation pressure 0.8MPa, temperature 50°C, time 2h, permeate liquid was separated with a membrane separator with a molecular weight cut-off of 500Da, separation pressure 0.8MPa, temperature 30°C, time 2h, to obtain oligopeptides liquid; the oligopeptide liquid is concentrated to a solid content of 20% by a three-effect external circulation vacuum concentrator, and then spray-dried. The drying conditions are an inlet temperature of 170°C and an outlet temperature of 90°C to obtain food-grade low-salt marine fish oligopeptide powder.

After measurement, the food-grade low-salt marine fish oligopeptide powder prepared in this example has a yield of 15.34%, an oligopeptide content of 88.71%, a protein hydrolyzate below 1000Da of 90.83%, a salt content of 2.45%, a moisture content of 5.26%, and an ash content of 3.17%.

Example 3

Food-grade marine low-fat fishmeal is accurately weighed by a measuring scale, mixed with pure water in a pre-desalination mixing tank according to the mass ratio of material to water 1:10, set the temperature at 50°C, stirring at a speed of 60r/min, washed with water for 30min, and then passed through 100 mesh The pre-desalted fish meal is obtained by pressure filtration with a diaphragm filter press, and the desalination rate is 94.8%; the pre-desalted fish meal is transported to the enzymatic hydrolysis pre-mixing tank through a screw conveyor, and pure water is injected according to the mass ratio of material and water at 1:6, and stirred at 60r/min After mixing, it is pumped into the colloid mill through the screw pump, and the pre-desalted fish meal particles are ground and pulverized to 100 mesh by the colloid mill, and then transported to the enzymolysis tank through the screw pump to prepare for enzymolysis; the temperature is controlled at 55°C and pH8.5, according to the bottom Add Novozymes alkaline protease NS37071 to 1% of the amount of the substance, and hydrolyze for 0.5h until the pH drops to 7.0, then add 1% Novozymes neutral protease Neutrase0.8L, and continue to hydrolyze for 4.5h; Transport it to the enzyme inactivator through a screw pump and raise the temperature to 98°C to inactivate the enzyme for 10 minutes, and use a 100-mesh diaphragm filter press and a 200-mesh bag filter to remove the slag to obtain an enzymatic hydrolysis solution for slag removal; enzymatic hydrolysis for slag removal After the liquid is sterilized by a pasteurizer, it enters the membrane separation system. First, a membrane separator with a molecular weight cut-off of 10,000Da is used to separate the enzymolysis liquid. The separation pressure is 1.2MPa, the temperature is 45°C, and the time is 1h. 150Da membrane separator for separation, separation pressure 0.8MPa, temperature 45°C, time 2h, to obtain the oligopeptide liquid; the oligopeptide liquid was concentrated to a solid content of 30% by a three-effect external circulation vacuum concentrator, then spray-dried, dried The condition is that the inlet temperature is 180°C, and the outlet temperature is 90°C to obtain food-grade low-salt marine fish oligopeptide powder.

After determination, the food-grade low-salt marine fish oligopeptide powder prepared in this example has a yield of 25.74%, an oligopeptide content of 90.51%, a protein hydrolyzate below 1000Da of 92.63%, a salt content of 3.88%, a moisture content of 4.83%, and an ash content of 4.82%.

Example 4

Food-grade marine low-fat fish meal is accurately weighed by a measuring scale, mixed with pure water in a pre-desalination mixing tank according to the mass ratio of material and water at 1:2, set the temperature at 5°C, stirred at a speed of 40r/min, washed with water for 5min, and passed through 40 mesh Pre-desalted fish meal is obtained by pressure filtration with a diaphragm filter press, with a desalination rate of 94.8%; the pre-desalted fish meal is transported to the enzymatic hydrolysis pre-mixing tank through a screw conveyor, and pure water is injected according to the mass ratio of material to water at 1:4, and stirred at 60r/min After mixing, it is pumped into the colloid mill through the screw pump, and the pre-desalted fish meal particles are ground and pulverized to 40 mesh by the colloid mill, and then transported to the enzymolysis tank through the screw pump to prepare for enzymolysis; the temperature is controlled at 40°C and the pH is 8.5. Add Novozymes alkaline protease NS37071 to 0.1% of the amount of the substance, and hydrolyze for 0.5h until the pH drops to 7.0, then add 1% Novozymes neutral protease Neutrase 0.8L, and continue to hydrolyze for 2.5h; Transport it to the enzyme inactivator through a screw pump and raise the temperature to 80°C to inactivate the enzyme for 10 minutes, and use a 40-mesh diaphragm filter press and a 100-mesh bag filter to remove the slag to obtain the enzymatic hydrolysis solution for slag removal; enzymatic hydrolysis for slag removal After the liquid is sterilized by a pasteurizer, it enters the membrane separation system. Firstly, the membrane separator with a molecular weight cut-off of 1000Da is used to separate the enzymolysis liquid. The separation pressure is 0.4MPa, the temperature is 20°C, and the time is 30min. 150Da membrane separator for separation, separation pressure 1.2MPa, temperature 60°C, time 180min, to obtain the oligopeptide liquid; the oligopeptide liquid was concentrated to a solid content of 10% by a three-effect external circulation vacuum concentrator, then spray-dried, dried The condition is that the inlet temperature is 160°C and the outlet temperature is 80°C to obtain food-grade low-salt marine fish oligopeptide powder.

After measurement, the food-grade low-salt marine fish oligopeptide powder prepared in this example has a yield of 23.95%, an oligopeptide content of 88.45%, a protein hydrolyzate below 1000Da of 91.12%, a salt content of 3.95%, a moisture content of 4.97%, and an ash content of 4.82%.

Example 5

Food-grade marine low-fat fish meal is accurately weighed by a measuring scale, mixed with pure water in a pre-desalination mixing tank according to the mass ratio of material to water at 1:15, set the temperature at 50°C, stirred at a speed of 100r/min, washed with water for 60min, and passed through 200 mesh The pre-desalted fish meal is obtained by pressure filtration with a diaphragm filter press, and the desalination rate is 94.8%; the pre-desalted fish meal is transported to the enzymatic hydrolysis pre-mixing tank through a screw conveyor, and pure water is injected according to the mass ratio of material to water at 1:15, and stirred at 60r/min After mixing, it is pumped into the colloid mill through the screw pump, and the pre-desalted fish meal particles are ground and pulverized to 80 mesh by the colloid mill, and then transported to the enzymolysis tank through the screw pump to prepare for enzymolysis; the temperature is controlled at 65°C and the pH is 8.5. Add Novozymes alkaline protease NS37071 to 5% of the substance, and hydrolyze for 2 hours until the pH drops to 7.0, then add 5% Novozymes neutral protease Neutrase 0.8L, and continue enzymatic hydrolysis for 4 hours; The pump is transported to the enzyme inactivator and the temperature is raised to 99°C to inactivate the enzyme for 25 minutes, and the 200-mesh diaphragm filter press and the 400-mesh bag filter are respectively used to remove the slag to obtain the deslagging enzymatic solution; the deslagging enzymatic solution is passed through After being sterilized by the pasteurizer, it enters the membrane separation system. First, the enzymolysis solution is separated by a membrane separator with a molecular weight cut-off of 10,000Da. The separation pressure is 0.4MPa, the temperature is 20°C, and the time is 30min. Membrane separator for separation, separation pressure 1.2MPa, temperature 60 ° C, time 180min, to obtain oligopeptide liquid; oligopeptide liquid was concentrated to a solid content of 10% by a three-effect external circulation vacuum concentrator and then spray-dried. The drying conditions were: The inlet temperature is 200°C, and the outlet temperature is 100°C to obtain food-grade low-salt marine fish oligopeptide powder.

After measurement, the food-grade low-salt marine fish oligopeptide powder prepared in this example has a yield of 16.04%, an oligopeptide content of 89.22%, a protein hydrolyzate below 1000Da of 91.05%, a salt content of 2.34%, a moisture content of 4.99%, and an ash content of 3.25%.

Claims (9)

1. A preparation method of food-grade low-salt marine fish oligopeptide powder, characterized in that, comprising the steps: (1) Washing and pre-desalination, that is, add food-grade marine low-fat fishmeal and pure water into the pre-desalination mixing tank according to the mass ratio of feed to water 1:2-15, set the temperature at 5-50°C, and stir at a speed of 40-100r/min. Wash with water for 5-60 minutes, and then filter through a 40-200-mesh diaphragm filter press to obtain pre-desalted fish meal; (2) Grinding and pulverizing by colloid mill, that is, conveying the pre-desalted fish meal to the enzymolysis pre-mixing tank through the screw conveyor, and injecting pure water according to the mass ratio of material to water of 1:4-15, stirring and mixing, and then pumping in through the screw pump Colloid mill, use the colloid mill to grind the pre-desalted fish meal particles to 40-80 mesh, increase the surface area of the fish meal particles, and facilitate contact with enzymes; (3) Enzymolysis, adjust the pH value to 6.0-10.0, add protease, control the mass ratio of protease to substrate to 0.1-5%, enzymolysis at 40-65°C for 3-6 hours; 99°C, inactivate the enzyme for 10-25 minutes; after cooling, pass through a 40-200-mesh diaphragm filter press and a 100-400-mesh bag filter to remove slag by one filter press and two filter slag removal to obtain the enzymatic solution; (4) Membrane separation, that is, first use the first 1000-10000Da ultrafiltration membrane to intercept the macromolecular peptides and pigments in the enzymatic hydrolysis solution, and then use the second 150-500Da nanofiltration membrane to separate and remove the membrane permeate Free amino acid and residual salt to obtain oligopeptide solution with molecular weight less than or equal to 1000Da, separation temperature is 20-60°C, pressure is 0.4-1.2MPa, time is 30-180min; (5) Concentration and spray drying, that is, first use a three-effect external circulation vacuum concentrator to concentrate the solid content of the oligopeptide solution to 10-30%, and then use a spray drying tower to control the inlet air temperature at 160-200°C. The wind temperature is 80-100°C, and the oligopeptide solution is dried to obtain food-grade low-salt marine fish oligopeptide powder. 2. The preparation method of food-grade low-salt marine fish oligopeptide powder according to claim 1, characterized in that, the washing pre-desalination described in step (1), its process conditions are: the mass ratio of material to water is 1: 10. The temperature is 50°C, and the washing time is 20 minutes. 3. The method for preparing food-grade low-salt marine fish oligopeptide powder according to claim 1, characterized in that the filter press equipment described in step (1) is a 40-200 mesh diaphragm filter press. 4. The method for preparing food-grade low-salt marine fish oligopeptide powder according to claim 1, characterized in that the colloid mill described in step (2) is ground and pulverized, and the process conditions are: the mass ratio of material to water is 1 :6, time 20min, the pre-desalted fish meal particles were ground and pulverized to 80 mesh. 5. The preparation method of food-grade low-salt marine fish oligopeptide powder according to claim 1, characterized in that the food-grade industrialized protease preparation described in step (3) is alkaline protease and neutral protease, two The amount of protease added was 1% of the substrate mass, the enzymolysis temperature was 55°C, the pH values were 8.5 and 7.5, and the time was 5h. 6. The method for preparing food-grade low-salt marine fish oligopeptide powder according to claim 1, characterized in that the first filter press and the second filter described in step (3) are 40-200 mesh respectively Diaphragm filter press and 100-400 mesh bag filter. 7. The method for preparing food-grade low-salt marine fish oligopeptide powder according to claim 1, characterized in that, for the membrane separation described in step (4), an ultrafiltration membrane used has a molecular weight cut-off of 10000Da The roll-type membrane module, the separation temperature is 45°C, the pressure is 1.2MPa, and the time is 40min; the roll-type membrane assembly with the molecular weight cut-off of the second nanofiltration membrane is 150Da, the separation temperature is 40°C, the pressure is 0.8MPa, and the time is 60min. 8. The preparation method of food-grade low-salt marine fish oligopeptide powder according to claim 1, characterized in that in step (5), the oligopeptide liquid is concentrated to the solid content by using a three-effect external circulation vacuum concentrator 30%, the inlet air temperature of spray drying is 180°C, and the outlet air temperature is 90°C. 9. the preparation method of food-grade marine fish oligopeptide powder according to claim 1, is characterized in that, described food-grade marine low-fat fish meal is the low-fat fish protein powder that marine low-value fish is made through degreasing, Crude protein content 55-75%, moisture ≤ 10.0%, crude fat ≤ 4.0%.