WO2020014888A1

WO2020014888A1 - Application of sericin peptide in inhibiting browning of fruits and vegetables

Info

Publication number: WO2020014888A1
Application number: PCT/CN2018/096127
Authority: WO
Inventors: 陈俊宏; 陈宗棠; 李祐丞
Original assignee: 岱妮国际生技有限公司
Priority date: 2018-07-18
Filing date: 2018-07-18
Publication date: 2020-01-23

Abstract

An application of sericin peptide in inhibiting browning of fruits and vegetables, comprising: separating sericin in natural silk from fibroin, and retaining the sericin; hydrolyzing the sericin using an enzyme so as to hydrolyze same into micromolecular peptides; spraying or coating the sericin peptides on a cut surface of vegetables and fruits after high-temperature sterilization; and chelating copper ions in phenolic oxiddase or tyrosinase enzyme by means of the sericin peptide, so as to inhibit the browning of the fruits and vegetables caused by phenolic oxiddase or tyrosinase enzyme.

Description

Application of sericin as an inhibitor of browning of fruits and vegetables

[0001] The present invention relates to an application for inhibiting browning of vegetables and fruits, and in particular, to spraying or coating a sericin peptide onto a slice of vegetables and fruits to inhibit the browning reaction of vegetables and fruits due to oxidation.

Background technique

[0002] The browning reaction of food is because the polyphenols contained in vegetables and fruits are oxidized, a condensation reaction occurs, and the brown matter becomes. For example, cut apples, lotus roots, or potatoes are a phenomenon that food processing industry is not happy with. The key enzyme that causes this reaction is tyrosinase, which is a phenol oxidase. The active center of this enzyme is two divalent copper ions. When copper ions are oxidized when they contact oxygen in the air, they will be oxidized in fruits and vegetables. The surface becomes brown, and as time goes by, the color becomes darker, which will affect the sale of fruits and vegetables, which is not welcomed by the food industry.

[0003] The prior art inhibits the browning reaction of this type of enzyme by chelating copper ions in tyrosinase. At present, the food processing industry's control of enzyme-type browning reaction is mainly the addition of chemical metal ion chelator "ethylene diamine tetraacetate disodium acetate (EDTA Na ₂ )" or "ethylene diamine tetraacetate disodium calcium (EDTA CaNa ₂ ) ".

Summary of invention

technical problem

[0004] However, although ethylene diamine tetraacetic acid disodium (EDTA Na ₂ ) or ethylene diamine tetraacetic acid disodium (EDTA CaNa ₂ ) are legal food additives, they are always chemically synthesized, and they also cause renal failure, low The risk of symptoms such as blood pressure, shock, and irregular heartbeat. Because these two chemical additives are interface active agents, they can sequester or seize minerals and heavy metals in the blood, so they may affect the balance of ions in the body.

[0005] The main proteins of natural silk are sericin and fibroin. Silk fibroin is the structural center of silk, and the viscous substance around it is sericin. Sericin accounts for about 20% to 30% of the total silk protein. It is a water-soluble polymer protein with good biodegradability, biocompatibility, and metal chelating ability. Therefore, it has a wide range of applications in cosmetics, medicine, and food. Potential application value.

Problem solution

Technical solutions [0006] The object of the present invention is to provide a sericin peptide as an application for inhibiting browning of vegetables and fruits, including utilizing the strong chelating ability of sericin peptide and metal to chelate the phenol oxidase or Copper ions to inhibit browning of vegetables and fruits.

[0007] In order to achieve the above-mentioned object, the technical means is to use the properties of silk sericin and silk fibroin to be different in water solubility in silk, extract sericin aqueous solution, and use enzymes to cut the protein into small molecule peptides, because To be applied to food, it needs to be made into sericin peptide solution after high temperature sterilization, and then sprayed or coated on the cut surface of vegetables and fruits. Use the strong chelating ability of sericin and metal to chelate phenol oxidase or tyramine Copper ions in acid enzymes to inhibit browning of fruits and vegetables. Because the molecular weight of the peptide is much smaller than that of protein, and its stability to heat and acid is higher than that of protein, it also has better solubility relative to protein. Therefore, the liquid phase of the sericin peptide of the present invention has better chelating effect than protein. .

[0008] The present invention provides an application of sericin peptide for inhibiting browning of vegetables and fruits, including spraying and / or coating sericin peptide solution on fruits and vegetables to chelate copper ions of tyrosinase in fruits and vegetables To further suppress the browning reaction of vegetables and fruits, wherein the sericin peptide liquid is produced through the following steps:

[0009] Step 1: Take natural silk or flat cocoon, wash it with clean water at high temperature for several times, and then degumme with reverse osmosis water at 80 ° C to 100 ° C for 40 ~ 70 minutes, then remove the water-insoluble silk Cardioprotein, which remains sericin dissolved in aqueous solution;

[0010] Step 2: Add 0.3% ~ 0.7% of the papaya enzyme in the product volume of step 1, and perform preliminary hydrolysis by shaking at 40 ° C ~ 60 ° C for 6 hours. The concentration of the papaya enzyme used is 8 ~ 12 units / mg;

[0011] Step 3: Add 0.5% ~ 1.0% papaya enzyme by volume to the product in Step 2 and shake at 40 ° C ~ 60 ° C

6 hours of advanced hydrolysis, this step can be repeated multiple times according to the degree of hydrolysis of sericin to peptides;

[0012] Step 4: remove centrifugal fibroin remaining in the product of step 3 by centrifugation or filtration;

Step 5: Add volume ratio

Alkaline protease with a concentration of 0.5 unit / ml ~ 1.5

Unit / ml was shaken at 45 ° C for 6 hours for complete hydrolysis;

[0014] Step 6: autoclaving the product of Step 5 while removing the activity of the added protease to stop its reaction; and

[0015] Step 7: The sterilized product is the sericin peptide solution, which can be sprayed or coated on the surface of vegetables and fruits as a browning inhibitor after dilution to a concentration of not more than 2 pg / ml.

[0016] Wherein, the washing temperature in step 1 is 90 ° C. [0017] Among them, the concentration of papaya enzyme is 10 units / mg.

[0018] Wherein, the hydrolysis temperature in step 2 and step 3 is 50 ° C.

The beneficial effects of the invention

Brief description of the drawings

BRIEF DESCRIPTION OF THE DRAWINGS

1 is a block flowchart of the present invention.

The best embodiment for carrying out the invention

Best Mode of the Invention

[0020] In order to facilitate the further understanding and understanding of the technical means and operation process of the present invention, examples are given in conjunction with the drawings, and the detailed description is as follows.

[0021] Please refer to FIG. 1. The present invention relates to the use of sericin peptide to inhibit browning of vegetables and fruits, and extracting sericin peptide from silk, the steps include:

[0022] Step 1: Take natural silk or flat cocoon, wash it with clean water at high temperature for many times, and then degumme with high temperature reverse osmosis water for 40 ~ 70 minutes, preferably 60 minutes, and then insoluble by centrifugation or filtration Sericin was removed from the water, and sericin remained in the aqueous solution.

[0023] Step 2: The above-extracted sericin is firstly added with papain and subjected to preliminary hydrolysis for 6 hours with shaking at 40 ° C ~ 60 ° C, wherein the optimal hydrolysis temperature is 50 ° C. The amount of papaya enzyme added in this step is 0.3% ~ 0.7% of the product volume in step 1, the best is 0.5%, and the concentration of papaya enzyme is 8 ~ 12 units / mg, and the best is 10 units / mg.

[0024] Step 3: In step 2, a papaya enzyme with a volume ratio of 0.5% to 1.0% is further added, and advanced hydrolysis is performed after shaking at 40 ° C ~ 60 ° C for 6 hours, and the optimal hydrolysis temperature is 50 ° C.

[0025] Step 4: Since fibroin is insoluble in water, the remaining fibroin in the product of step 3 is removed by centrifugation or filtration.

[0026] Step 5: Add volume ratio

Alcalase, its concentration is 0.5 unit / ml ~ 1.5 unit / ml and shaken at 45 ° C for 6 hours for complete hydrolysis. The best alkaline protease concentration is 1 unit / ml

[0027] Step 6: The product of Step 5 is subjected to high temperature sterilization, at the same time, the activity of the added protease is removed, and its reaction is stopped. Should.

[0028] Step 7: The sterilized product is the sericin peptide solution of the present invention, which can be used directly, or stored under low temperature, frozen and dried.

[0029] Step 8: Dissolve the dried sericin peptide powder in sterile water to form a sericin peptide solution, which can be sprayed or coated on the cut surface of vegetables and fruits to chelate phenol oxidase or tyramine The copper ions in the acid enzyme can inhibit the browning of vegetables and fruits.

[0030] The high temperature of step 1 refers to 80 ° C to 100 ° C, where the washed part is preferably 90 ° C, and the reverse osmosis water degumming part is added at 100 ° C.

[0031] Steps 2 and 3 can be repeated multiple times depending on the degree of hydrolysis of the sericin to the peptide.

[0032] The sericin peptide solution used in the present invention may be used at a concentration of up to 2 pg / ml.

[0033] After the sericin solution of the present invention is sprayed or coated on the cut surface of vegetables and fruits, it will replace the oxygen in the air to chelate the copper ions of phenol oxidase or tyrosinase, so the copper ions will not be oxidized. Therefore, the browning reaction does not occur on the cut surface of vegetables and fruits. Moreover, sericin peptide is originally a natural product. After taking fruits and vegetables coated with sericin peptide, its sericin peptide will be decomposed into amino acids in the small intestine. After being absorbed, it can be supplemented with natural amino acids to further synthesize the human body. Required protein.

[0034] The component that can inhibit the browning of vegetables and fruits is a sericin peptide with a small molecule. First, the peptide has a molecular weight smaller than that of protein, so it is easier to be absorbed after entering the human body. Secondly, the ratio of victory to protein has higher thermal and acid stability. And the solubility of peptide is better than protein. Since the present invention is applied to food, although silk is a natural material, some bacteria may be contacted during the process of obtaining and producing sericin peptide. For food safety, the sericin solution of the present invention needs to be sterilized at high temperature. If a protein is used as an inhibitor, the protein loses its activity due to denaturation during the high-temperature sterilization process, and then loses its ability to chelate copper ions. Therefore, the present invention uses sericin peptides.

[0035] However, what is described above is only the preferred embodiments of the present invention, and the scope of implementation of the present invention cannot be limited by this; therefore, any simple equivalent changes made according to the claims of the present invention and the contents of the description and Modifications should still fall within the protection scope of the present invention.

Claims

Claim

[Claim 1] An application of sericin peptide for inhibiting browning of vegetables and fruits, characterized in that it comprises spraying and / or coating sericin peptide solution on the cut surface of vegetables and fruits to chelate tyrosinase in vegetables and fruits Copper ions, thereby inhibiting the browning reaction of vegetables and fruits, wherein the sericin peptide liquid is generated through the following steps:

Step 1: Take natural silk or flat cocoons, wash them with clean water at high temperature for several times, and then degump them with reverse osmosis water at 80 ° (: to 100 °) for 40 to 70 minutes, and then remove the water-insoluble silk core Protein, retain sericin dissolved in aqueous solution;

Step 2: Add 0.3% ~ 0.7% of papaya enzyme from Step 1 and shake at 40 ° C ~ 60 ° C for 6 hours. The concentration of papaya enzyme used is 8 ~ 12 units / mg. Step 3: Step 2 is added with papaya enzyme in a volume ratio of 0.5% to 1.0%, and further hydrolyzed by shaking at 40 ° C to 60 ° C for 6 hours. This step can be repeated multiple times according to the degree of hydrolysis of sericin into peptide.

Step 4: Use centrifugation or filtration to remove the fibroin remaining in the product from Step 3; Step 5: Add the volume ratio

Alkaline protease with a concentration of 0.5 unit / ml ~ 1.5 unit / ml and shaken at 45 ° C for 6 hours for complete hydrolysis;

Step 6: sterilize the product of Step 5 at the same time while removing the activity of the added protease to stop its reaction; and

Step 7: The sterilized product is the sericin peptide solution, which can be sprayed or coated on the surface of vegetables and fruits as a browning inhibitor after dilution to a concentration of not more than 2 pg / ml.

[Claim 2] The use of the sericin peptide according to claim 1 for inhibiting browning of vegetables and fruits, characterized in that, the washing temperature in step 1 is 90 ° C.

[Claim 3] The use of the sericin peptide according to claim 1 for inhibiting browning of vegetables and fruits, characterized in that the concentration of papaya enzyme is 10 units / mg.

[Claim 4] The use of the sericin peptide according to claim 1 for inhibiting browning of vegetables and fruits, characterized in that the hydrolysis temperature in step 2 and step 3 is 50 ° C.