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CN-122004287-A - High-temperature-resistant modified embedded nisin and application thereof in processing of high-temperature baked eggs

CN122004287ACN 122004287 ACN122004287 ACN 122004287ACN-122004287-A

Abstract

The invention relates to the technical field of roast chicken egg corrosion prevention, in particular to high-temperature-resistant modified embedded nisin and application thereof in processing of high-temperature roast chicken eggs. Comprises nisin, hydroxypropyl-beta-cyclodextrin coated outside a nisin non-antibacterial hydrophobic region, and non-denatured type-I collagen coated outside nisin and hydroxypropyl-beta-cyclodextrin, wherein the non-denatured type-I collagen forms a continuous porous network structure. After the modified embedded nisin is applied to the processing of high-temperature baked eggs, the total colony count of the baked eggs is smaller than 10 3 CFU/g, and the modified embedded nisin has excellent antibacterial effect on gram-negative bacteria of escherichia coli, has a storage period of 3 months and prolongs the shelf life.

Inventors

  • ZHAO HONGMEI
  • ZHAO KUN
  • QU HUI
  • LIU XIAOLIN

Assignees

  • 爱康食品(青岛)有限公司

Dates

Publication Date
20260512
Application Date
20260227

Claims (10)

  1. 1. The high-temperature-resistant modified embedded nisin is characterized by comprising nisin, hydroxypropyl-beta-cyclodextrin wrapped on the outer side of a nisin non-antibacterial hydrophobic region, and non-denatured type-I collagen wrapped on the outer sides of nisin and hydroxypropyl-beta-cyclodextrin, wherein the non-denatured type-I collagen forms a continuous porous network structure.
  2. 2. The modified temperature-resistant nisin-embedded nisin as claimed in claim 1, wherein the modified nisin-embedded nisin has an antibacterial effect on both gram-negative and gram-positive bacteria.
  3. 3. The modified temperature resistant embedded nisin of claim 1, wherein the nisin bacteria inhibiting zone is targeted to bind bacteria across the pores of the non-denatured type I collagen network.
  4. 4. The modified temperature-resistant embedded nisin of claim 1, wherein nisin is obtained by fermentation of lactococcus lactis, and hydroxypropyl-beta-cyclodextrin is added at a later stage of fermentation to improve nisin activity.
  5. 5. The method for preparing the modified and embedded nisin with high temperature resistance according to any one of claims 1 to 4, which is characterized in that: (1) Preparation of nisin-hydroxypropyl-beta-cyclodextrin compositions: slowly dripping the nisin aqueous solution into the hydroxypropyl-beta-cyclodextrin aqueous solution under the stirring conditions of 25-30 ℃ and 150-200 rpm, magnetically stirring for 2-3 hours after dripping, and standing the mixed solution in a cold storage way at 4 ℃ for 12 hours after stirring to obtain a nisin-hydroxypropyl-beta-cyclodextrin composition; (2) Preparation of modified embedded nisin: Slowly dripping an undenatured type I collagen aqueous solution into the nisin-hydroxypropyl-beta-cyclodextrin composition obtained in the step (1) under the stirring conditions of 30-35 ℃ and 100-150 rpm, adding a composite buffer aqueous solution until the final concentration of the composite buffer aqueous solution is 0.02-0.05 mol/L, regulating the pH value of the solution to be 6.5-7.0, continuously stirring for 4-6 hours, enabling the undenatured type I collagen to form a porous network structure through self-assembly, refrigerating and standing for 8 hours at 4 ℃ after stirring is finished, and solidifying the porous network structure to obtain a modified embedded nisin solution; (3) Freeze-drying and preserving: Centrifuging the modified embedded nisin solution at the temperature of 4 ℃ and the speed of 20000-30000 rpm for 30-60 min, adding a freeze-drying protective agent into the precipitate obtained by centrifugation, and freeze-drying for 20-28 h to obtain modified embedded nisin powder.
  6. 6. The method for preparing high-temperature-resistant modified embedded nisin according to claim 5, wherein the molar ratio of nisin to hydroxypropyl-beta-cyclodextrin is 1:1-1:2, and the mass ratio of nisin to non-denatured type-I collagen is 1:3-1:5.
  7. 7. The method for preparing high temperature resistant modified embedded nisin according to claim 5, which is characterized in that: the nisin aqueous solution is prepared by using sterile water, the concentration of the solution is 1.0-2.0 mg/mL, and the pH is 6.0-6.5.
  8. 8. The method for preparing high temperature resistant modified embedded nisin according to claim 5, which is characterized in that: The hydroxypropyl-beta-cyclodextrin aqueous solution is prepared by using sterile water, and the concentration is 2.0-4.0 mg/mL; the non-denatured type I collagen aqueous solution is prepared by using sterile water, and the concentration is 3.0-5.0 mg/mL.
  9. 9. The method for preparing high temperature resistant modified embedded nisin according to claim 5, which is characterized in that: The composite buffer is a sodium citrate-sodium dihydrogen phosphate buffer with a pH of 6.5-7.0.
  10. 10. Use of a modified, temperature resistant embedded nisin according to any one of claims 1-4 in the processing of high temperature baked eggs, characterized in that: (1) Egg shelling and filtering Selecting fresh, breakage-free and odor-free washing-free sterile eggs, checking the integrity and cleanliness of eggshells, and ensuring no signs of cracks, stains or deterioration; Placing the eggs in a sheller, and removing eggshells; pouring the shelled egg liquid into a filter with an 80-mesh filter screen, and filtering residual eggshell fragments and lacing impurities to obtain primarily purified egg liquid; (2) Blending and fine filtering Adding the egg liquid after rough filtration into a blending tank, adding auxiliary materials according to a formula, and stirring for 5-8 minutes at a speed of 300-500 rpm by a stirrer to fully and uniformly mix the egg liquid with the auxiliary materials to obtain a blended egg liquid; Simultaneously taking freeze-dried modified embedded nisin powder, re-dissolving the modified embedded nisin powder to 0.05-0.1g/mL by using sterile water, stirring the powder at 30 ℃ and 100rpm for 10min to form uniform dispersion liquid, adding the re-dissolved modified embedded nisin solution into prepared egg liquid, and adding 10mL of modified embedded nisin solution into each kg of prepared egg liquid; The blended egg liquid is filtered for the second time through a 120-mesh filter screen, so that fine impurities are further removed, and the fine and smooth texture of the egg liquid is ensured; (3) Baking and cooling Injecting the egg liquid after fine filtration into a mould, wherein the baking temperature is more than 100 ℃, the baking time is more than 6 minutes, and observing the solidification state of the egg liquid until the surface is uniformly golden yellow and the interior is completely cooked; Demoulding after baking to obtain shaped baked egg embryo body, and avoiding the embryo body contacting with greasy dirt or impurities during cooling; (4) Inspection product and bagging Detecting appearance, smell and taste of the roasted chicken egg embryo, and removing unqualified products with surface cracking, uneven color and smell; Packaging qualified roast chicken eggs into food-grade composite packaging bags according to set weight, vacuumizing by using a vacuum packaging machine, and sealing to ensure that the packaging bags are free of air leakage and flat in sealing; (5) Secondary sterilization and cooling Placing the sealed packaging bag into a sterilizing pond, and sterilizing bacteria and mold microorganisms in the packaging bag by pasteurization; Placing the sterilized product into a cooling tank, and cooling to below 15 ℃; (6) Detecting and warehousing Detecting whether metal, glass and stone foreign matters are mixed in the product by an X-ray foreign matter detector, further checking the fine metal impurities by a metal detector to ensure the safety of the product, putting the qualified product into a carton, attaching a production date and a quality guarantee period mark after sealing the carton, sending the carton into a constant temperature and humidity warehouse with the temperature of 0-8 ℃ and the humidity of less than or equal to 75%, and storing the carton until the carton is taken out of the warehouse.

Description

High-temperature-resistant modified embedded nisin and application thereof in processing of high-temperature baked eggs Technical Field The invention relates to the technical field of roast chicken egg corrosion prevention, in particular to high-temperature-resistant modified embedded nisin and application thereof in processing of high-temperature roast chicken eggs. Background Nisin (Nisin) is an approved natural antibacterial peptide, and the metabolite of Nisin is amino acid, has high safety, has broad-spectrum inhibition effect on gram-positive pathogenic bacteria such as bacillus cereus, staphylococcus aureus and the like, and is widely applied to the field of food preservation. The high-temperature baked chicken egg products are popular food products, and the processing process has strict requirements on the high temperature resistance and the pH resistance of the preservative, and has definite requirements on the corrosion prevention safety and the targeting property. However, nisin suffers from three major technical drawbacks in the processing and application of high temperature baked egg products, severely limiting its practical use: 1. The high temperature resistance is poor, the alpha-helix conformation of nisin is easy to unfold in an environment with the temperature of more than 60 ℃, the activity of the nisin is easy to be lost when an egg product is baked at high temperature, and the effective antibacterial activity cannot be maintained; 2. The pH resistance is weak, namely the isoelectric point of nisin is about 8.5, the pH range of an egg processing system is 6.5-7.0, the solubility of nisin is low in the environment, and an amide bond is easy to hydrolyze, so that the antibacterial activity of nisin is lost; 3. the traditional nisin is in an indiscriminate dispersion state in a food matrix, is easily adsorbed by proteins and lipids in the matrix to be inactivated, cannot precisely target pathogenic bacteria, not only has low antiseptic efficiency, but also needs to be increased to ensure the effect, and in addition, has a broad-spectrum inhibition effect on gram-positive pathogenic bacteria, and cannot inhibit the gram-negative pathogenic bacteria. Although partial nisin modification schemes exist in the prior art, the method has obvious limitations that partial schemes adopt chemical crosslinking modification to improve stability, but have safety risks of generating toxic byproducts, and simple nisin inclusion technology can only slightly improve the stability of nisin, can not solve three core problems of high temperature resistance, pH resistance and targeted bacteriostasis at the same time, and is easy to block the bacteriostasis sites of nisin due to encapsulation, so that bacteriostasis is invalid. Therefore, developing a modified embedded nisin which can be used for high Wen Kaoji egg products, has high temperature resistance, polar pH resistance and targeted antibacterial functions, and meets the food-grade safety standard is a problem to be solved at present. Disclosure of Invention The invention aims to overcome the existing defects and provide a high-temperature-resistant modified embedded nisin and application thereof in processing of high-temperature baked eggs so as to solve the problems related to the background technology. In order to achieve the above purpose, the present invention provides the following technical solutions: a modified embedded nisin with high temperature resistance comprises nisin, hydroxypropyl-beta-cyclodextrin wrapped outside a nisin non-antibacterial hydrophobic region, and non-denatured type-I collagen wrapped outside nisin and hydroxypropyl-beta-cyclodextrin, wherein the non-denatured type-I collagen forms a continuous porous network structure. Furthermore, the modified embedded nisin has antibacterial effect on gram-negative bacteria and gram-positive bacteria. Furthermore, the hydroxypropyl-beta-cyclodextrin does not wrap the bacteriostasis area of nisin, and the bacteriostasis area of nisin penetrates through the pores of the non-denatured type-I collagen to be combined with bacteria in a targeting way. The nisin is obtained by fermentation of lactococcus lactis, and hydroxypropyl-beta-cyclodextrin is added in the later period of fermentation to improve the activity of nisin. A preparation method of high-temperature resistant modified embedded nisin, (1) Preparation of nisin-hydroxypropyl-beta-cyclodextrin compositions: slowly dripping the nisin aqueous solution into the hydroxypropyl-beta-cyclodextrin aqueous solution under the stirring conditions of 25-30 ℃ and 150-200 rpm, magnetically stirring for 2-3 hours after dripping, and standing the mixed solution in a cold storage way at 4 ℃ for 12 hours after stirring to obtain a nisin-hydroxypropyl-beta-cyclodextrin composition; (2) Preparation of modified embedded nisin: Slowly dripping an undenatured type I collagen aqueous solution into the nisin-hydroxypropyl-beta-cyclodextrin composition obtain