JP3098337B2 - Collagen beads and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a collagen bead and a method for producing the same.

[0002]

2. Description of the Related Art Bead-shaped molded articles using biopolymers such as proteins and polysaccharides have been conventionally used as beads or immobilized carriers for physiologically active substances.

[0003] As a beaded food, for example, Japanese Unexamined Patent Publication No.
JP-A-1-79755 discloses a low-temperature gelling and edible aqueous sol such as gelatin, which is cooled and gelled by cooling, and the formed gelled particles are further coated with a film-forming sol.
There has been proposed a method for producing a fish-egg-like food in which a gelling film layer is formed by contact with a gelling agent. Also, Japanese Patent Publication No. 45-111
No. 01 proposes to provide a granular alginate gel by treating alginate with a bivalent metal ion that can be ingested into the body.

[0004] As a bead-shaped molded article using collagen, Japanese Patent Publication No. 64-1169 describes a method for producing collagen beads to be used as a carrier for immobilizing a physiologically active substance. This method is a method in which a spherical shape is formed in an organic solvent that is hardly miscible or immiscible with water and then cured.

[0005] However, a collagen bead-shaped molded article usable for food has not been developed.

[0006]

In the above-mentioned conventional method for producing collagen beads, a high-concentration aqueous solution of collagen substance is used, and in the production process, a hardly miscible or immiscible organic solvent is used. I have. Generally, many hardly miscible or immiscible organic solvents are harmful to the human body, and when beads are produced using the same, mixing and remaining of the organic solvent in the beads poses a problem. Further, in the conventional method, metal salts such as aldehydes and chromium are used for curing collagen, and it is difficult to use the beads thus obtained in foods.

[0007]

SUMMARY OF THE INVENTION The present invention provides a method for solidifying formed beads by using a low-concentration aqueous solution of a collagen substance and using no organic solvent so that no organic solvent is mixed into the beads. It is highly safe when the substance is used as a food, and furthermore, it enables industrial production of collagen beads in large quantities.

The present inventor has found that a solvent other than an organic solvent which is hardly miscible or immiscible is used. We continued our research. as a result,
It has been found that collagen beads can be formed by dropping an aqueous solution of a collagen substance into an aqueous solution of tannin, which is a natural organic compound often contained in foods and medicines. Furthermore, by holding the formed collagen beads in a tannin aqueous solution,
The tannins were found to penetrate into the collagen beads and solidify the collagen beads.

From these facts, a method for producing the above-mentioned collagen beads, which is different from the conventional method and which enables the formation and solidification of the beads by a single operation, has been completed.

Based on this finding, the present inventors have completed the present invention by examining the concentration of a collagen substance in an aqueous solution of a collagen substance, the concentration of a tannin in an aqueous tannin solution, the pH of a tannin solution, and the like necessary for forming collagen beads.

Collagen constitutes connective tissues such as bones and skins of animals, and is a rod-shaped body having a molecular weight of 300,000, a length of 300 nm and a thickness of 1.5 nm forming a helical structure composed of three peptide chains. It is a protein that is hardly soluble in water. Also,
Collagen, unlike gelatin, does not gel at low temperatures, but when the helical structure formed from the three peptide chains of collagen is thermally decomposed into gelatin, it gels by cooling even at a concentration of about 1%. I do.

An aqueous solution of a collagen substance that can be used as a raw material in the present invention is collagen solubilized by the action of an enzyme or alkali (see Japanese Patent Publication Nos. 44-11037 and 46-15033). The collagen material concentration of the aqueous solution of collagen material for forming collagen beads is about 0.1 to about 15.0% by weight,
Preferably it is 0.2 to 1.5% by weight. The tannins are not particularly limited, and those included in the general definition of tannins such as "a water-soluble polyphenol compound of plant origin, which becomes turbid and precipitates in solution with proteins, alkaloids, etc." Can be used arbitrarily.

The concentration of the aqueous tannin solution may be any concentration at which the aqueous collagen solution can maintain the beads in the solution, and the range is from about 0.1 to saturation, preferably from 1.0 to 10.0% by weight. The pH may be within a range where tannin is not oxidized, and is usually about 2 to about 7, preferably about 2 to about 4.

As described above, tannin generally forms turbidity and precipitates in solution with proteins. In particular, when gelatin obtained by denaturation of collagen is added to a tannin solution, it is immediately diffused, causing turbidity and precipitation, and is therefore used for the tannin qualitative method. The collagen substance, which is a raw material of the present invention, is a protein, but turbidity does not occur within the above-mentioned collagen substance concentration range. However, this aqueous solution of collagen substance becomes a precipitate in its shape when dropped into the aqueous tannin solution. Therefore, when the collagen substance concentration of the aqueous collagen substance solution is high, the viscosity of the aqueous liquid is high, so that when the aqueous solution of the collagen substance is dropped into the tannin aqueous solution, the beads are formed into drops. When the collagen substance concentration is low, the aqueous collagen substance solution is formed into spherical beads. Further, when the concentration is lower than the range, when dropped into the tannin aqueous solution,
The aqueous collagenous solution is diffused into small fragments that become turbid, as do other proteins.

The particle size of the collagen beads can be freely determined by changing the size of the droplet, the concentration of the collagen substance in the aqueous solution of the collagen substance, the tannin concentration of the tannin aqueous solution as the immersion liquid, and the like. For example, when an aqueous solution of a collagen substance having a concentration of about 0.1 to about 15.0% by weight is dropped into a tannin aqueous solution having a concentration of about 0.1 to a saturation concentration from a capillary having an inner diameter of 0.5 mm, the particle size of the collagen beads is determined by the collagen substance concentration and the tannin concentration. 2.0 depending on concentration
Or 4.0mm. Similarly, when dripping from a tube having an inner diameter of 3 mm, about 3.0 to about 8.
Can be changed to 0mm. In the case of dripping from a tube having an inner diameter of 10 mm, it can be changed to about 10.0 mm to about 30.0 mm.

According to the present invention, the aqueous solution of collagen substance is dropped into the aqueous solution of tannin to form droplets composed of the aqueous solution of collagen material in the aqueous solution of tannin. Thereafter, the formed collagen beads are allowed to stand while gently stirring the tannin aqueous solution, whereby the tannin permeates into the collagen beads and is solidified. Further, the structure between the surface portion and the inside of the beads can be changed by adjusting the permeation time. Although it depends on the collagen substance concentration and the tannin concentration of the tannin aqueous solution to be immersed, usually, when the immersion time is within 10 minutes, collagen beads having a two-layer structure in which the outer surface is solidified and the inside maintains the state of the aqueous liquid, Become. If soaked for 30 minutes or more, the collagen beads will be uniformly solidified. Therefore, the amount of tannin based on the collagen substance of the collagen beads according to the present invention can be freely changed depending on the concentration of the tannin aqueous solution and the immersion time.

Further, the collagen beads are stable even at around the collagen denaturation temperature of 37 ° C. due to the action of tannin, indicating that the heat resistance has been improved.

By mixing a substance other than collagen into the aqueous solution of collagen substance, collagen beads containing the substance can be formed. For example, 1 part by weight of about 60,000 to about 90,000 for 5 parts by weight of collagen material
Dextran with a molecular weight distribution of 0.1
Collagen beads produced by dropping into 10.0% by weight tannin aqueous solution can be left at pH 4.0 for 5 hours in a solution.
0.1% dextran eluted from collagen beads
It is as follows. However, the substance that can be included is a polymer having a molecular weight of about 60,000 or more, and preferably, in addition to the dextran, a water-soluble protein such as BSA, starch, pectin, and carrageenan, or a polysaccharide. However,
Even if it is hardly soluble or insoluble, any material can be used as long as it does not aggregate or separate in the aqueous collagen solution and is sufficiently diffused.

Further, as a method for encapsulating an oily substance such as lipid in collagen, the oily substance is emulsified with an aqueous collagen solution and then dropped into a tannin solution to form beads in the tannin solution in an emulsified state. It is solidified. This makes it possible to produce a collagen substance containing an emulsified oily substance in the solidified collagen beads.

Further, by using a biaxial coaxial tube, the above-mentioned aqueous solution of collagen substance is simultaneously extruded from an outer tube, and various aqueous solutions or oily substances are simultaneously extruded from an inner tube and dropped into a tannin solution, whereby a bead surface is formed. It is also possible to produce collagen beads in which the part is solidified and which contains a liquid or gel of a substance other than collagen inside.

On the other hand, low molecular substances such as amino acids and oligosaccharides are:
Since the collagen beads can be freely permeated in the solution, it is also possible to equilibrate the beads and the solution to contain a low-molecular substance by immersing the collagen beads in a solution of such a substance. .

An object of the present invention is to provide a collagen bead that can be used for food and a method for producing the same. Since the collagen beads in the present invention are substantially prepared from collagen and tannin, unlike conventional methods, they are suitable for food.

It can also be used as a food, for example, a fish egg-like food having an outer film portion and an inner solution-like portion, a confectionery, etc.
In that case, a substance other than collagen, for example, a coloring agent, a seasoning and the like can be included. With regard to coloring, collagen beads having a gray to black color can be produced by dipping in a solution containing trivalent iron, particularly by utilizing the fact that collagen and tannin are used.

Furthermore, since the collagen beads of the present invention do not contain heavy metals and the like, they can also be used as immobilized carriers that are entrapped without inactivating physiologically active substances such as enzymes.

In the case of collagen beads formed into beads in a tannin solution, the use of a curing agent selected from an aldehyde, a metal salt or a combination thereof makes it possible to produce collagen beads having higher hardness and higher heat resistance. It is possible. The tannin in the collagen beads after being cured by the curing agent can be removed by washing with an aqueous solution having a pH of 10.0 or more. This makes it possible to prepare beads hardened by a hardener used in a conventional method without using an organic solvent that is hardly miscible or immiscible with water.

Hereinafter, the present invention will be described in more detail with reference to examples, but these examples do not limit the present invention.

[0027]

Example 1 An aqueous enzyme-solubilized collagen solution (pH 5.0, concentration 1.0% by weight) was sufficiently degassed under reduced pressure. This is flowed through a 0.5 mm diameter nozzle using a peristaltic pump 2.
The solution was added dropwise at 0 ml / min to an aqueous solution of tannic acid (pH 3.0, concentration 5.0% by weight). After the dropping, the tannic acid aqueous solution was left for 2 hours with gentle stirring, and then sufficiently washed with distilled water. Uniform collagen beads with a diameter of 2.8 ± 0.1 mm were obtained.

[0028]

Example 2 An aqueous enzyme-solubilized collagen solution (pH 3.0, concentration 0.5% by weight) was sufficiently degassed under reduced pressure. This is flowed through a 0.5 mm diameter nozzle using a peristaltic pump 2.
Grape seed tannic acid aqueous solution (pH 3.0, concentration at 0 ml / min)
7.5% by weight).

The grape seed tannins were separated as follows. That is, 100 g of grape seeds were crushed, defatted sufficiently with hexane, and then polyphenol was extracted with 100 ml of 50% ethanol. This extract was concentrated under reduced pressure to remove ethanol, and then the precipitate was removed by centrifugation. After diethyl ether was added to the supernatant and stirred well, the aqueous layer was collected and freeze-dried, and the obtained powder was used as grape seed tannin.

After the dropping, the grape seed tannin aqueous solution was left for 2 hours with gentle stirring. Collagen beads were taken out from the grape seed tannin aqueous solution, and sufficiently washed with distilled water. Uniform collagen beads having a diameter of 2.4 ± 0.1 mm were obtained.

[0031]

Example 3 1.0% by weight enzyme-solubilized collagen solution (pH
After mixing 3.0) and 1.0% by weight of an alkali method gelatin at 30 ° C., the mixture was defoamed under reduced pressure. Using a peristaltic pump, the tannin aqueous solution (pH
4.0, concentration 3.0% by weight). Within 1 minute after dropping, the beads were taken out from the tannin aqueous solution and immersed in a 10% sodium chloride solution for 2 hours. This gives a particle size of 5.2
Texture that resembles a sol-like fish egg with ± 0.1mm inside
A fish egg-like food with is obtained.

[0032]

[Example 4] Outer tube with outer diameter of 4 mm and inner diameter of 3 mm, outer diameter of 1.2 mm, inner diameter of 1 m
A 1.0% by weight enzyme-solubilized collagen aqueous solution (pH 8.0) was flowed into the outer tube of a double nozzle having a biaxial coaxial tube having an inner tube of m, and soybean oil was allowed to flow through the inner tube. Flow rate of 1ml
Using two peristaltic pumps, the aqueous solution of the enzyme-solubilized collagen and the soybean oil were dropped into a 5% aqueous solution of tannic acid (pH 3.0) so that the flow rate of the inner tube was 0.5 ml / min. After holding for 10 minutes after dropping, the beads were taken out of the tannic acid solution. After thoroughly washing the removed beads with distilled water,
It was immersed in a 5.0% sodium chloride solution for 2 hours. As a result, a fish egg-like food having a particle size of 4.5 ± 0.1 mm and a texture similar to a fish egg containing soybean oil therein was obtained.

[0033]

Example 5 An aqueous alkali-solubilized collagen solution (pH 3.
(0, concentration: 2.0% by weight), 50 mg (2,000 units) of invertase, a sugar hydrolase, was added to and mixed and dissolved, and then defoamed using a cooling centrifuge. This is placed in a syringe container and a tannic acid solution (pH 3.0,
(Concentration: 2.0% by weight). After the dropwise addition, the tannin solution was allowed to stand at 4 ° C. for 4 hours while being gently stirred.
The immobilized invertase having a particle size of 2.5 ± 0.1 mm was prepared by sufficiently washing with an aqueous solution of the above. The immobilized invertase composed of this collagen bead is used as a substrate with sucrose as a pH.
When the enzyme activity was measured in the 4.0 solution, the activity was sufficiently maintained.

[0034]

Example 6 A 0.5% by weight aqueous solution of collagen solubilized in enzyme (pH 3.0) and soybean oil were mixed and emulsified in a ratio of 3: 1. This was dropped into a tannic acid aqueous solution (pH 3.0, concentration 5.0% by weight) from a nozzle having a diameter of 0.5 mm using a peristaltic pump.
Beads were taken out of the tannic acid aqueous solution within 2 minutes after the dropping. The extracted beads were colored gray by immersing in a 0.5% iron chloride aqueous solution for 30 seconds, and then immersed in a 5.0% sodium chloride solution for 2 hours. This resulted in a caviar-like food having a color and texture similar to caviar.

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁷ , DB name) C08J 3/00-3/28 A61L 1 / 32,1 / 238 A23P 1/02

Claims (9)

(57) [Claims] 1. Collagen beads comprising solubilized collagen and tannin. 2. Collagen beads formed by dropping an aqueous solution of a collagen substance into a tannin solution. 3. The collagen beads according to claim 1, wherein the collagen beads are fish egg-like foods. 4. The collagen bead according to claim 1, wherein the collagen bead is an immobilization carrier. 5. The collagen beads according to claim 1, wherein the collagen beads contain an oily substance and various aqueous liquids. 6. A method for producing collagen beads, wherein an aqueous solution of a collagen substance is dropped into a tannin solution to form beads. 7. The method according to claim 6, wherein the aqueous solution of collagen material is solubilized collagen. 8. The method according to claim 6, wherein the aqueous collagen solution has a collagen concentration of 0.1 to 15.0% by weight. 9. The tannin aqueous solution has a tannin concentration of 0.1% by weight to saturation and a pH of 2 to 10.
The method according to any one of claims 6 to 8, wherein