Method for preparing keratin powder from decalcified fish scales

Abstract

The invention discloses a method for preparing keratin powder from decalcified fish scales, which comprises the following steps: S1, sequentially cleaning, degumming and filtering the decalcified fish scales to respectively obtain a fish scale collagen liquid and a fish scale endoplasm layer; s2, performing enzymolysis on the fish scale collagen liquid by using neutral protease to obtain fish collagen liquid; s3, adding the fish scale endoplasmic layer into a 1% calcium hydroxide solution for alkalization treatment to obtain a product A; s4, adding a 2% phosphoric acid solution into the product A for neutralization until the pH is 6-6.5 to obtain a product B; s5, decolorizing and filtering the product B to obtain a keratin extracting solution; s6, sequentially carrying out vacuum concentration, sterilization and spray drying on the keratin extracting solution to obtain the keratin powder. The method has the characteristics of short production period, high treatment degree, low production cost and high yield.

Description

Technical Field

[0001] The invention relates to a method for preparing keratin powder, in particular to a method for preparing keratin powder by utilizing decalcified fish scales. Background Art

[0002] Keratin is a sulfur-containing protein that is mainly found in animal keratin, such as the stratum corneum, wool, nails, and scales. The components of keratin mainly include two types: α-keratin and β-keratin. α-keratin is a smaller keratin that is mainly found in the stratum corneum and forms a fish scale-like arrangement through dehydration and oxidation reactions. The amino acid composition of α-keratin is similar to that of β-keratin, but it contains more cysteine ​​residues and has stronger hardness and toughness. β-keratin is a larger keratin that is mainly found in hair and nails. β-keratin has a large molecular weight, a compact structure, and contains a variety of sulfur bonds and cross-linked structures, so it has strong heat resistance and chemical resistance. Keratin is widely used in health products and cosmetics.

[0003] The existing method of extracting fish scale keratin usually adopts enzymatic hydrolysis for soaking extraction, but this method takes a long time, generally requiring 12-48 hours, requires a large amount of enzyme, equivalent to 5-8% of the substrate, has high production costs, and the keratin in the fish scale cannot be completely extracted, resulting in a low yield. Summary of the invention

[0004] The purpose of the present invention is to provide a method for preparing keratin powder by using decalcified fish scales. The present invention has the characteristics of short production cycle, high processing degree, low production cost and high yield.

[0005] The technical solution of the present invention is a method for preparing keratin powder by using decalcified fish scales, comprising the following steps:

[0006] S1, washing, degumming and filtering the decalcified fish scales in sequence to obtain fish scale collagen liquid and fish scale endoplasmic layer respectively;

[0007] S2, enzymolyzing the fish scale collagen solution with a neutral protease to obtain fish collagen solution;

[0008] S3, adding the fish scale endoplasmic layer to a 1% by mass calcium hydroxide solution for alkalization, stirring and alkalizing at 95-100° C. for 1.0-1.5 hours to obtain product A;

[0009] S4. Add 2% by mass phosphoric acid solution to product A for neutralization until the pH is 6 to 6.5 to obtain product B;

[0010] S5, decolorizing and filtering product B using activated carbon to obtain a keratin extract;

[0011] S6. The keratin extract is sequentially subjected to reduced pressure concentration, sterilization, and spray drying to obtain keratin powder.

[0012] In the aforementioned method for preparing keratin powder using decalcified fish scales, in step S1, the degumming method of the decalcified fish scales is: degumming is carried out by boiling at 90 to 100° C. for 0.8 to 1.2 hours.

[0013] In the aforementioned method for preparing keratin powder using decalcified fish scales, in step S2, the input amount of neutral protease is 0.4-0.6% of the amount of substrate, and the enzymatic hydrolysis time is 2.5-3.5 hours to obtain fish collagen solution.

[0014] In the aforementioned method for preparing keratin powder using decalcified fish scales, in step S5, the weight of the activated carbon is 1% of the total material weight.

[0015] In the aforementioned method for preparing keratin powder using decalcified fish scales, in step S6, the temperature of reduced pressure concentration is 60-80° C., and the vapor pressure of reduced pressure concentration is 0.4-0.6 MPa.

[0016] In the aforementioned method for preparing keratin powder using decalcified fish scales, in step S6, the sterilization temperature is 100-110° C., and the sterilization time is 10-15 min.

[0017] In the aforementioned method for preparing keratin powder using decalcified fish scales, in step S6, the inlet air temperature of the spray drying is 180-190°C, and the outlet air temperature of the spray drying is 120-130°C.

[0018] In the aforementioned method for preparing keratin powder using decalcified fish scales, in step S5, product B is filtered using a plate and frame filter, the plate and frame filter comprising a frame, a plurality of filter units are arranged on the frame, each filter unit is provided with a mounting frame, adjacent mounting frames are connected by a connecting rope, the mounting frame is provided with a sliding sleeve, a pulley and a protrusion, the frame is provided with a sliding rod passing through each sliding sleeve, a sliding seat for sliding connection of the pulley and a linear slide, the linear slide is provided with a manipulator moving along the plurality of filter units, the manipulator is rotatably connected with an arc-shaped elastic pull rod, a limit block is provided above the transition portion of the elastic pull rod, a compression spring is provided at the bottom of the elastic pull rod, a pair of automatic flaps opened or closed by cylinder drive are provided below the filter unit, and a conveyor belt is provided below the automatic flap.

[0019] In the aforementioned method for preparing keratin powder using decalcified fish scales, the frame is also provided with a gantry that moves along the filtering unit, a winch is provided on the top of the gantry, two steel ropes are wound around the drum of the winch, the two steel ropes are respectively passed around the guide wheels at both ends and connected to the movable plates located on both sides of the gantry, a pair of cleaning plates are provided between the two movable plates, a brush and a first nozzle are provided on the opposite sides of the two cleaning plates, the bottom end of the cleaning plate is rotatably connected to a rocker arm via a rotating shaft, a fan-shaped gear is provided on the rotating shaft, a driving gear driven by a motor is meshed on the fan-shaped gear, and a knocking block is provided on the rocker arm.

[0020] In the aforementioned method for preparing keratin powder using decalcified fish scales, the filtration unit includes a membrane filter plate, filter cloths are provided on both sides of the membrane filter plate, and an activated carbon layer is provided between the filter cloth and the membrane filter plate; a water inlet extrusion pipe is provided on the frame, and a hose connected to the chamber inside the membrane filter plate is provided on the water inlet extrusion pipe; a water inlet flushing pipe is provided on the upper part of the filtration unit, and a second nozzle is provided on the water inlet flushing pipe.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The present invention adopts decoction degumming, and then the fish scale collagen liquid is enzymolyzed with neutral protease, and the fish scale endoplasmic layer is alkalized and then neutralized, so as to obtain two products: fish collagen and fish scale keratin. The two proteins are extracted at one time, are easy to separate, and are suitable for the needs of different customers. The total extraction time of the present invention is 5-6 hours, the process is simple, the production cycle is short, and the amount of neutral protease added is 0.5% of the amount of substrate, which can meet the required requirements, the amount of enzyme added is small, the production cost is low, and the yield of fish scale keratin can reach 25%, and the yield is stable.

[0023] The present invention uses a 1% by mass calcium hydroxide solution to perform alkaline hydrolysis on the fish scale endoplasmic layer, and uses a 2% by mass edible phosphoric acid solution to neutralize it, thereby generating insoluble calcium phosphate, which can be removed by subsequent filtration and separation. The operation is convenient, and the salt content of the reaction solution is guaranteed to be minimized, thereby ensuring the taste and quality of the product and reducing impurities.

[0024] Therefore, the present invention has the characteristics of short production cycle, high processing degree, low production cost and high yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of the present invention.

[0026] Figure 2 It is a structural diagram of the robot.

[0027] Figure 3 It is a structural diagram of the automatic flip board.

[0028] Figure 4 It is a schematic diagram of the structure of the cleaning plate.

[0029] Figure 5 It is a structural schematic diagram of the filter unit.

[0030] The markings in the attached drawings are: 1, frame; 11, slide bar; 12, slide seat; 13, water inlet squeeze pipe; 14, hose; 15, water inlet flushing pipe; 16, second nozzle; 17, linear slide; 2, filter unit; 21, diaphragm filter plate; 22, filter cloth; 23, activated carbon layer; 3, mounting frame; 31, connecting rope; 32, sliding sleeve; 33, pulley; 34, bump; 4, manipulator; 41, elastic pull Rod; 411, limit block; 42, compression spring; 5, automatic flap; 51, cylinder; 52, conveyor belt; 6, gantry; 61, winch; 611, wire rope; 612, guide wheel; 62, moving plate; 63, guide groove; 7, cleaning plate; 71, guide rod; 72, brush; 73, first nozzle; 74, rocker arm; 75, sector gear; 76, driving gear; 77, knocking block. DETAILED DESCRIPTION

[0031] The present invention will be further described below in conjunction with the embodiments, but they are not intended to limit the present invention.

[0032] Embodiment 1:

[0033] A method for preparing keratin powder by using decalcified fish scales comprises the following steps:

[0034] S1, washing, degumming and filtering the decalcified fish scales in sequence to obtain fish scale collagen liquid and fish scale endoplasmic layer respectively;

[0035] The degumming method of decalcified fish scales is: degumming by boiling at 100°C for 1 hour.

[0036] The method for filtering decalcified fish scales is: filtering through gauze at around 70°C.

[0037] S2, enzymolyzing the fish scale collagen solution with neutral protease, the input amount of neutral protease is 0.5% of the substrate amount, enzymolyzing for 3 hours, and obtaining a small molecular weight fish collagen solution. The solid content of the fish collagen solution is 25%, and the extraction reaches about 150kg.

[0038] The neutral protease used is cheap and has a short enzymatic hydrolysis time. The entire enzymatic hydrolysis process does not require pH adjustment, is easier to operate, and has a good taste. It is the best enzymatic hydrolyzer for fish collagen. Fish collagen liquid mainly contains glycine, lysine, proline, hydroxyproline, etc.

[0039] S3, adding the fish scale endoplasmic layer to a 1% by mass calcium hydroxide solution for alkalization, stirring and alkalizing at a slightly boiling state of 98° C. for 1 hour to obtain product A;

[0040] S4. Add 2% by mass phosphoric acid solution to product A for neutralization to form a calcium phosphate precipitate with a solubility of 0.0025%, until the pH reaches 6. The solution neutralization reaction is basically completed, and the obtained product is weakly acidic. The produced calcium phosphate precipitate is easy to filter and remove, and the calcium ions in calcium hydroxide can be fully removed to obtain a relatively pure product B;

[0041] S5. Decolorize and filter product B using activated carbon at 1% by weight of the total material to obtain a fish scale keratin extract;

[0042] S6, the keratin extract is sequentially subjected to reduced pressure concentration at 80°C and a steam pressure of 0.5Mpa, sterilized at 105°C for 15 minutes, and spray dried, the inlet air temperature of the spray dried is 185°C, the outlet air temperature of the spray dried is 125°C, evaporation and sterilization are performed simultaneously, saving operation time, and fish scale keratin powder is obtained. Keratin powder mainly contains leucine, tyrosine, and serine.

[0043] The invention hydrolyzes and alkalizes the fish scale endoplasmic layer by using a calcium hydroxide solution with a mass percentage of 1%, so that the disulfide bonds and long peptide bonds in the fish scale endoplasmic layer are broken, and short peptide keratin is obtained to form soluble keratin. The stirring alkalization treatment state is maintained at a slight boiling point, so that the fish scale endoplasmic layer can be gradually dissolved to the end without residue, and the hydrolysis time is short, the hydrolysis rate is high, and the cost is low.

[0044] Then, a 2% by mass edible phosphoric acid solution is used to neutralize the residual alkali, and the neutralization reaction formula is: 3Cac(oH)2+2H3Po4→Ca3(Po4)2↓+H2O; the generated calcium phosphate is a sparingly soluble salt, which is precipitated in the reaction solution and is easy to separate and can be removed by filtering, thereby achieving the purpose of desalination, ensuring that the salt content of the reaction solution is minimized, ensuring the taste and quality of the product, and reducing impurities.

[0045] The keratin powder prepared by the invention is a light yellow or white powder, has a molecular weight of 2000D, a keratin yield of 25%, and a purity of fish scale keratin of 99.99. The coliform group is ≤30mpn / 100g, the protein is ≥90.0%, the moisture is ≤6.0%, the lead content is ≤1.0mg / kg, the mercury content is ≤0.3mg / kg, the arsenic content is ≤0.5mg / kg, the pH value is 4.0-6.0, and the total number of bacteria is ≤1000cfu / g.

[0046] like Figure 1-5As shown, in step S5, product B is filtered by a plate and frame filter, wherein the plate and frame filter comprises a frame 1, on which a plurality of filter units 2 are arranged, each filter unit 2 is provided with a mounting frame 3, adjacent mounting frames 3 are connected with a connecting rope 31 of a certain length, the mounting frame 3 is provided with a sliding sleeve 32, a pulley 33 and a protrusion 34, the frame 1 is provided with a sliding rod 11 passing through each sliding sleeve 32, a sliding seat 12 for sliding connection of the pulley 33 and a linear slide 17, the linear slide 17 is provided with a manipulator 4 moving along the plurality of filter units 2, the manipulator 4 is rotatably connected with an arc-shaped elastic pull rod 41, a limit block 411 is provided above the transition portion of the elastic pull rod 41, a compression spring 42 is provided at the bottom of the elastic pull rod 41, a pair of automatic flaps 5 opened or closed by a cylinder 51 are provided below the filter unit 2, and a conveyor belt 52 is provided below the automatic flap 5.

[0047] A liquid inlet pipe is provided at the center of the filter unit 2, and a liquid outlet pipe is provided at the bottom of the filter unit 2. Product B is input from the liquid inlet pipe into the filter units 2 distributed in layers for filtration, and impurities are blocked in the filter units 2. The filtered keratin extract is discharged from the liquid outlet pipe. When the filter unit 2 needs to be cleaned, the manipulator 4 pulls the protrusions 34 on the mounting frame 3 in sequence, so that the filter units 2 are separated one by one, so that the filter residue attached to the filter unit 2 falls off, and it is convenient to clean the filter unit 2. One end of the automatic flap 5 is rotatably connected to the frame 1, and the manipulator 4 pulls the filter units 2 to separate from each other. At the same time, the cylinder 51 drives the automatic flap 5 to rotate, and the two automatic flaps 5 open to each other in a funnel shape, so that the filter residue in the filter unit 2 falls onto the conveyor belt 52 along the automatic flap 5 and is conveyed out through the conveyor belt 52.

[0048] The elastic pull rod 41 on the manipulator 4 is arc-shaped. When the manipulator 4 moves forward from one side of the mounting frame 3 to the other side, the protrusion 34 squeezes the elastic pull rod 41 to compress it so that the manipulator 4 moves smoothly to the other side of the mounting frame 3, and then the manipulator 4 moves in the opposite direction. At this time, the elastic pull rod 41 abuts against the protrusion 34 and will not be compressed, thereby driving the mounting frame 3 and the filter unit 2 to move and separate from the other filter units 2.

[0049] A connecting rope 31 of a certain length is connected between adjacent mounting frames 3. When one of the filter units 2 is pulled open by the manipulator 4, the remaining filter units 2 can be pulled apart through the connecting rope 31 to separate them from each other, thereby achieving the purpose of rapid unloading and cleaning and shortening the cleaning cycle.

[0050] The frame 1 is also provided with a gantry 6 that moves along the filtering unit 2, a winch 61 is provided on the top of the gantry 6, two steel wire ropes 611 are wound on the drum of the winch 61, the two steel wire ropes 611 are respectively passed around the guide wheels 612 at both ends and connected to the moving plates 62 located on both sides of the gantry 6, a pair of cleaning plates 7 is provided between the two moving plates 62, a bidirectional screw is threadedly connected between the two cleaning plates 7, one end of the bidirectional screw is provided with a driving motor, a guide groove 63 is provided on the moving plate 62, a guide rod 71 passing through the guide groove 63 is provided on the cleaning plate 7, a brush 72 and a first nozzle 73 are provided on the opposite side of the two cleaning plates 7, the bottom end of the cleaning plate 7 is rotatably connected to a rocker arm 74 via a rotating shaft, a fan gear 75 is provided on the rotating shaft, a driving gear 76 driven by a motor is meshed on the fan gear 75, and a knocking block 77 is provided on the rocker arm 74.

[0051] The gantry 6 moves along the filter unit 2 on the frame 1 through walking wheels or linear modules, and the set winch 61 drives the two cleaning plates 7 to move up and down along the two sides of the filter unit 2 through the wire rope 611 to clean the filter unit 2, and drives the two cleaning plates 7 to move closer or farther from each other through the bidirectional screw, so as to adjust the spacing between the two cleaning plates 7 to match the filter units 2 of different widths; during cleaning, the cleaning plate 7 mechanically brushes and rinses the filter unit 2 with high-pressure water through the brush 72 and the first nozzle 73 to remove the filter residue and impurities on the filter unit 2; at the same time, through the cooperation of the active gear 76 and the fan gear 75, the rocker arm 74 is driven to swing back and forth, thereby driving the knocking block 77 to knock the filter unit 2 back and forth, accelerating the falling of the residual filter residue on the filter unit 2, and improving the thoroughness and comprehensiveness of the cleaning of the filter unit 2.

[0052] The filter unit 2 includes a membrane filter plate 21, filter cloths 22 are provided on both sides of the membrane filter plate 21, and an activated carbon layer 23 is provided between the filter cloth 22 and the membrane filter plate 21; a water inlet squeeze pipe 13 is provided on the frame 1, and a hose 14 connected to the chamber inside the membrane filter plate 21 is provided on the water inlet squeeze pipe 13; a water inlet flushing pipe 15 is provided on the upper part of the filter unit 2, and a second nozzle 16 is provided on the water inlet flushing pipe 15.

[0053] While product B is filtered through the filter cloth 22 on the filter unit 2, it is also decolorized through the activated carbon layer 23 to remove the filter residue and discoloration, thereby obtaining a relatively pure keratin extract; the filtered filter residue is rinsed through the provided water inlet flushing pipe 15, and then clean water is introduced into the chamber inside the diaphragm filter plate 21 through the provided water inlet squeezing pipe 13 to push the diaphragm sheet of the diaphragm filter plate 21 to bulge toward the side of the filter cloth 22, and the filter residue is mechanically squeezed to recover the keratin extract remaining in the filter residue to a higher degree, thereby improving the extraction rate of the keratin extract.

[0054] It should be understood that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. For those skilled in the art, the technical solutions described in the above embodiments can be modified, or some of the technical features therein can be replaced by equivalents; and all these modifications and replacements should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A method for preparing keratin powder using decalcified fish scales, characterized in that: The following steps are involved: S1, washing, degumming and filtering the decalcified fish scales in sequence to obtain fish scale collagen liquid and fish scale endoplasmic layer respectively; S2, enzymolyzing the fish scale collagen solution with a neutral protease to obtain fish collagen solution; S3, adding the fish scale endoplasmic layer to a 1% by mass calcium hydroxide solution for alkalization, stirring and alkalizing at 95-100° C. for 1.0-1.5 hours to obtain product A; S4. Add 2% by mass phosphoric acid solution to product A for neutralization until the pH is 6 to 6.5 to obtain product B; S5, decolorizing and filtering product B to obtain keratin extract; S6. The keratin extract is sequentially subjected to reduced pressure concentration, sterilization, and spray drying to obtain keratin powder.

2. The method for preparing keratin powder by using decalcified fish scales according to claim 1, characterized in that: In step S1, the degumming method of the decalcified fish scales is: degumming is performed by boiling at 90 to 100° C. for 0.8 to 1.2 hours.

3. The method for preparing keratin powder by using decalcified fish scales according to claim 1, characterized in that: In step S2, the input amount of neutral protease is 0.4-0.6% of the amount of substrate, and the enzymatic hydrolysis time is 2.5-3.5 hours to obtain fish collagen solution.

4. The method for preparing keratin powder by using decalcified fish scales according to claim 1, characterized in that: In step S5, the weight of activated carbon is 1% of the total material weight.

5. The method for preparing keratin powder by using decalcified fish scales according to claim 1, characterized in that: In step S6, the temperature of the reduced pressure concentration is 60 to 80°C, and the vapor pressure of the reduced pressure concentration is 0.4 to 0.6 MPa.

6. The method for preparing keratin powder by using decalcified fish scales according to claim 1, characterized in that: In step S6, the sterilization temperature is 100-110°C and the sterilization time is 10-15 minutes.

7. The method for preparing keratin powder by using decalcified fish scales according to claim 1, characterized in that: In step S6, the inlet air temperature of the spray drying is 180-190°C, and the outlet air temperature of the spray drying is 120-130°C.

8. The method for preparing keratin powder by using decalcified fish scales according to claim 1, characterized in that: In step S5, product B is filtered using a plate-and-frame filter, wherein the plate-and-frame filter comprises a frame (1), a plurality of filter units (2) are arranged on the frame (1), each filter unit (2) is provided with a mounting frame (3), adjacent mounting frames (3) are connected by a connecting rope (31), the mounting frame (3) is provided with a sliding sleeve (32), a pulley (33) and a protrusion (34), and the frame (1) is provided with a sliding rod (11) passing through each sliding sleeve (32), and a sliding seat (12) for sliding connection with the pulley (33). and a linear slide (17), wherein a manipulator (4) is provided on the linear slide (17) and moves along a plurality of filter units (2), an arc-shaped elastic pull rod (41) is rotatably connected to the manipulator (4), a limit block (411) is provided above the transition portion of the elastic pull rod (41), a compression spring (42) is provided at the bottom of the elastic pull rod (41), and a pair of automatic flaps (5) that are opened or closed by being driven by a cylinder (51) are provided below the filter units (2), and a conveyor belt (52) is provided below the automatic flaps (5).

9. The method for preparing keratin powder by using decalcified fish scales according to claim 8, characterized in that: The frame (1) is also provided with a gantry (6) that moves along the filter unit (2), a winch (61) is provided on the top of the gantry (6), two steel wires (611) are wound around the drum of the winch (61), the two steel wires (611) respectively pass through guide wheels (612) at both ends and are connected to movable plates (62) located on both sides of the gantry (6), a pair of cleaning plates (7) is provided between the two movable plates (62), brushes (72) and a first nozzle (73) are provided on opposite sides of the two cleaning plates (7), the bottom end of the cleaning plate (7) is rotatably connected to a rocker arm (74) via a rotating shaft, a sector gear (75) is provided on the rotating shaft, a driving gear (76) driven by a motor is meshed on the sector gear (75), and a knocking block (77) is provided on the rocker arm (74).

10. The method for preparing keratin powder by using decalcified fish scales according to claim 8, characterized in that: The filtering unit (2) comprises a membrane filter plate (21), filter cloths (22) are provided on both sides of the membrane filter plate (21), and an activated carbon layer (23) is provided between the filter cloths (22) and the membrane filter plate (21); a water inlet squeeze pipe (13) is provided on the frame (1), and a hose (14) connected to a chamber inside the membrane filter plate (21) is provided on the water inlet squeeze pipe (13); A water inlet flushing pipe (15) is provided on the upper part of the filter unit (2), and a second nozzle (16) is provided on the water inlet flushing pipe (15).

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