JP2509390B2 - Method for purifying collagen peptide - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for purifying a collagen peptide, and more specifically, it is not only decolorized and deodorized by contacting the peptide obtained by enzymatic decomposition of collagen with a solid adsorbent under acidic conditions. The present invention relates to a method for purifying collagen peptide, which can completely prevent the occurrence of secondary sediment and can be suitably used for beverages and the like.

[0002]

BACKGROUND OF THE INVENTION Proteins are one of the most important nutrients for humans to survive, and proteins of animal or plant origin or microorganisms are used in all fields of the food industry. Not only is it advantageous to partially hydrolyze the protein and convert it into a peptide in order to improve the solubility of the protein and broaden its application, but also an amino acid mixture having the same absorption rate of di- and tripeptides. Its importance has been reconsidered since it was reported to be faster than the absorption rate from E. coli. Furthermore, the demand for peptides has been rapidly increasing with the recent increase in consumer needs for health foods or functional foods.

However, when a protein is enzymatically decomposed, a remarkable off-flavor including a bitter peptide is generally produced. Therefore, many conventional methods for enzymatically decomposing a protein that does not produce a bitter substance or a method for removing a bitter substance from a peptide have been known. Has been studied. For example, it is known to employ collagen or gelatin with a low content of amino acids that show a bitter taste in the raw material protein. Collagen contains about 14% by weight of amino acids showing a bitter taste, such as leucine, isoleucine, arginine, histidine, methionine, cystine, and tyrosine, but the amount thereof is less than that of other animal and plant proteins. There is an advantage that the degree of bitterness is small.

Conventionally, a hydrolyzate of collagen or gelatin (hereinafter referred to as collagen peptide) has a low molecular weight depending on the degree of hydrolysis, and has a low molecular weight as a corrigent, a rich body, a taste improver, and a slightly higher molecular weight. The large decomposed product is used as a quality improver for animal protein processed foods such as processed meat products or as an additive for breads, noodles, etc., and further used for alcoholic beverages such as sake, wine, beer, mirin, etc. It is used for lowering and clarifying agents.

On the other hand, since enzymatic decomposition products of soybean proteins are unavoidably accompanied by an offensive odor, it has been conventionally known to perform deodorizing treatment with activated carbon (JP-B-56-52543; JP-A-60-224460). See the bulletin). Further, for deodorizing soymilk, a method using a styrene / divinylbenzene-based porous adsorbent (see JP-A-58-126748) or a method using an adsorbent such as an ion exchange resin having an acidic substance adsorbing capacity ( Japanese Patent Publication No. 48-33378) is also proposed.

[0006]

In recent years, attention has been paid to the physiological functions of peptides, and their applications as health foods or nutrition / pharmaceutical products have been developed. Along with this, the characteristics of peptides are tasteless and odorless, as well as transparent solubility. However, there has been a demand for purified peptides that do not generate secondary precipitation. As described above, collagen peptide has less bitterness and off-flavor compared to soybean peptide, casein peptide, etc., and therefore, conventionally, it has been limited to simple decolorization and deodorization treatment with activated carbon or the like. However, according to the study by the present inventors, the commercially available collagen peptide prepared by the conventional method is not necessarily sufficiently purified, and for example,
In addition to the so-called decomposed odor, which is a strange off-flavor and coloring due to browning, when mixed with an aqueous solution such as a beverage, formation of sediment (precipitate) due to aggregation of peptides is inevitable over time. There is a serious drawback.
There is a problem that it is very difficult to remove such off-flavors and off-flavors, coloring and sediment-causing substances, and cannot be completely removed by a simple adsorption treatment using an adsorbent such as activated carbon.

[0007]

[Means for Solving the Problems] The present inventors have earnestly studied a method for preventing decolorization, deodorization and sedimentation of collagen peptides. As a result, they have found that the above problems can be solved all at once by adopting a specific pH range and temperature condition when the collagen peptide is subjected to a contact treatment with a solid adsorbent and completed the present invention. Therefore, the object of the present invention is
Another object of the present invention is to provide a collagen peptide which does not cause sedimentation over time even when it is blended in an off-flavor, an off-flavor, a coloring and a beverage.

According to the present invention, a peptide obtained by enzymatically degrading collagen is subjected to contact treatment with a solid adsorbent at a temperature of 20 to 70 ° C. under acidic conditions of pH 2.5 to 5. A purification method is provided.

As the collagen peptide which can be used in the present invention, gelatin obtained by heating animal dermis, tendon, ligament, fascia and the like for a long time with water is hydrolyzed with, for example, a protease. the average peptide chain length obtained that is approximately 2
-30, preferably about 2-10 oligopeptides can be mentioned. Such oligopeptides can be obtained by hydrolyzing gelatin etc. by a known method, and can also be easily obtained on the market.

Examples of solid adsorbents that can be used in the present invention include activated carbon, alumina, silica gel, activated clay, acid clay, styrene-divinylbenzene-based or methacrylic acid ester-based porous polymer resins. However, activated carbon is particularly preferable.

In the present invention, an aqueous solution of collagen peptide is contact-treated with an adsorbent as described above under acidic conditions of pH 2.5-5. Although the concentration of such an aqueous peptide solution can be arbitrarily selected, it is generally about 1 to about 40.
Concentrations of weight percent, preferably about 10 to about 30 weight percent, are often employed. If the pH of the aqueous peptide solution exceeds 5, the secondary precipitation-causing substance will be insufficiently removed. Further, even if the pH is lower than 2.5, the purification effect does not dramatically increase, but on the contrary, the amount of acid used for lowering the pH increases, and a new problem of removing the added acid is added. Occurs. The neutralization of such an acid has a serious adverse effect on taste due to salts produced. The most preferred pH range of the aqueous peptide solution is pH 3-4.

Examples of the acidic substance used for pH adjustment include organic acids such as acetic acid, citric acid, malic acid, tartaric acid, lactic acid and propionic acid; and inorganic acids such as hydrochloric acid and phosphoric acid. The amount of these acidic substances added may be an amount sufficient to bring the pH range above.

The pH of the collagen peptide aqueous solution thus adjusted is effectively deodorized and decolorized by contacting with the adsorbent as described above at 20 to 70 ° C., and added to a beverage or the like. It is possible to obtain a significantly improved purified peptide without the risk of occurrence of sediment.
When the contact treatment temperature with the adsorbent is lower than 20 ° C., it takes a long time to perform the treatment, which is industrially disadvantageous. In addition, the removal of the secondary precipitation-causing substance becomes insufficient. On the other hand, when the treatment temperature is higher than 70 ° C., heating odor is generated and browning occurs, which causes coloring, which is not preferable. The most preferable range of the contact treatment temperature is 50 to 60 ° C.

As a method of such contact treatment, an adsorbent may be added to the collagen peptide aqueous solution and the treatment may be carried out in a batch system under stirring or standing conditions. The amount of adsorbent added at that time is generally about 1 to about 40% by weight, preferably about 5 to about 20% by weight, based on the collagen peptide. A more preferable embodiment of the contact treatment is a continuous treatment method in which the aqueous solution is passed through a column packed with an adsorbent. As the conditions when the column system is adopted, the conditions such as the passage of SV of about 1 to about 5 under the above-mentioned pH and temperature conditions are often adopted.

After completion of the contact treatment with the adsorbent, it is desirable to carry out filtration. The filtration treatment can be carried out by a known method, and usually means such as centrifugal separation and vacuum filtration using diatomaceous earth or the like as an auxiliary agent are employed. The clear purified collagen peptide aqueous solution thus obtained can be subjected to heat sterilization treatment, if desired.

The collagen peptide obtained by the present invention has sufficient storage stability in the above-mentioned aqueous solution state, but if desired, it can be made into a dry powder by a known drying means such as vacuum drying or spray drying. . Less than,
Aspects of the present invention will be described more specifically with reference examples, examples and comparative examples.

[0017]

Examples Reference Example 1: Preparation of collagen peptide 1 kg of commercially available gelatin powder was added to 9 kg of purified water to disperse, and the mixture was heated at 40 to 50 ° C to dissolve it. Then 85 ℃
Heat sterilize for 15 minutes at room temperature, cool to 50 ° C and then Corolase R
50 g of a 10% aqueous solution of N (made by Rohm) was added to 50
Enzymatic decomposition was carried out for 5 hours with stirring at ℃ and pH 6.8. The resulting enzyme-decomposed solution was heated at 85 ° C. for 15 minutes to inactivate the enzyme, filtered with a filter paper, and spray-dried by a conventional method to obtain 930 g of a crude collagen peptide.

Comparative Example 1 200 g of the crude collagen peptide obtained in Reference Example 1 was added to 800 g of purified water and heated to 60 ° C. to dissolve it. The pH of the resulting solution was 6.3. 20 g of commercially available powdered activated carbon was added to this solution, and the mixture was stirred at 60 ° C. for 1 hour, and then the activated carbon was removed by filtration through diatomaceous earth to obtain 960 g of a 20% aqueous solution of purified collagen peptide (Comparative Product 1). Comparative Example 2 The crude collagen pellet obtained in Reference Example 1 was added to 800 g of purified water.
200 g of peptide was added, and the mixture was heated to 60 ° C. and dissolved. So
1.2 g of crystalline citric acid was added to the solution of pH 5.5.
Was adjusted. The obtained pH-adjusted solution was compared with Comparative Example 1.
Similarly, add 20g of powdered activated carbon and stir at 60 ° C for 1 hour.
And then filtered through diatomaceous earth to obtain 2 crude collagen peptides.
980 g of 0% solution was obtained (Comparative product 2). As in Example 1 Comparative Example 1, the crude collagen peptide 200g obtained in purified water 793g in Reference Example 1 was added a solution of pH6.3 was prepared by heating dissolved in 60 ° C., the crystal in a solution of their The pH was adjusted to 3.6 by adding 7 g of citric acid. The same pH activated powder 20 as in Comparative Example 1 was added to the obtained pH-adjusted solution.
g was added, the mixture was stirred at 60 ° C. for 1 hour, and then filtered through diatomaceous earth to obtain 980 g of a 20% solution of the purified collagen peptide (invention product 1).

Reference Example 2 The purified collagen peptides obtained in Comparative Examples 1 and 2 and Example 1 were adjusted to pH 3.6 with each of the three to prepare a sample solution, and the following evaluations were carried out.

(1) Coloring degree: Using a Hitachi spectrophotometer Model 228, the absorbance at a cell length of 1 cm and a wavelength of 420 nm was measured.

(2) Odor and taste: Regarding the sample solution,
Sensory evaluation was conducted by a panel of 10 people, and 5-level evaluation from − (no odor or taste) to ++++ (smell or taste is considerably strong) was performed, and the average value was shown.

(3) Ori stability: Beverages were prepared by mixing Comparative Product 1, Comparative Product 2 and Inventive Product 1 in the following blending ratios, respectively.
Fill a 250 ml transparent glass bottle, hot pack at 85 ° C, cool with water, and store in a thermostat at 37 ° C for 2 weeks.
The formation of sediment was observed. Evaluation is-(no tilt) ~ + (o
There are 5 steps from (with re-) to ++++ (large amount of tilt)
The average value is shown.

80% collagen peptide solution 75 g White sucrose 80 g Crystalline citric acid 3.5 g Water is added and dissolved to make 1 liter.

The results are shown in Table 1.

[0025]

[Table 1] As is clear from the results shown in Table 1, the purified collagen peptide of the present invention is more effective in removing odor and taste components than the comparative product, is less colored, and is free from the formation of sediment during storage. , The degree of purification was remarkably improved.

[0026]

EFFECT OF THE INVENTION The purified collagen peptide obtained by the present invention does not have the unpleasant odor such as fermentation odor or decomposed odor that the conventional peptides of this type have, and has no coloration. It is nutritious and easily soluble. Furthermore, as a notable effect, there is no risk of secondary turbidity or sediment when blended in a beverage or the like. According to the present invention, all of the currently commercially available collagen peptides or peptides derived from soybean, casein and other proteins cause turbidity with time to form a precipitate, which has a drawback of limited use. Will be resolved to. Since the purified collagen peptide obtained by the present invention has these excellent properties, it can be used for nutritional supplements, health foods, etc. without any limitation.

Claims (1)

(57) [Claims] 1. A peptide obtained by enzymatic degradation of collagen is added to a peptide of 20 to 70 under acidic conditions of pH 3 to 4.
A method for purifying a collagen peptide, which comprises contacting with a solid adsorbent at a temperature of ° C.