Edible enzyme crosslinking color drawing paint, preparation method and application

Abstract

The application provides an edible enzyme cross-linking color drawing coating, a preparation method and application, and belongs to the technical field of food packaging materials, and comprises the following components in percentage by weight: 4-10% of edible connecting material, 0.1-3% of biological cross-linking enzyme, 1-6% of microcapsule natural pigment, 1-5% of enzyme activity aid, 0.1-1% of rheological modifier, 1-5% of plasticizer, and the rest is solvent; the biological cross-linking enzyme comprises one or more combinations of glutamine transaminase, laccase, tyrosinase, polyphenol oxidase, peroxidase and lysine oxidase. The biological cross-linking enzyme is used to catalyze the connecting material and the casing substrate to form a covalent bond, so that the defects of weak adhesion and easy peeling of the traditional physical adsorption type coating are fundamentally overcome, the coating is non-toxic and non-residual, conforms to the clean label trend, realizes the perfect combination of food safety and excellent processing performance, and has high industrialization value.

Description

Technical Field

[0001] This invention relates to the field of food packaging materials technology, specifically to an edible enzyme-crosslinked paint, its preparation method, and its application. Background Technology

[0002] Creating colorful patterns on collagen casings is an important means of enhancing the visual appeal of meat products and achieving brand identification and product grading. In existing technologies, edible coatings used for casing painting are typically composed of edible binders and edible pigments, applied to the surface of the casing by printing, and then cured by drying or chemical cross-linking agents.

[0003] However, existing coatings have the following drawbacks: 1. Insufficient safety: Some coatings use chemical cross-linking agents, posing a risk of residue and failing to meet the trend of clean label food. 2. The coating has weak adhesion, and the adhesion between the coating and the casing substrate is mainly physical adsorption. It is easy to fall off and fade during processing such as steaming, smoking, and freezing, and the pigments are easy to migrate to the meat filling. 3. The cross-linking conditions are harsh. Chemical cross-linking often requires high temperature and strong acid / alkali environment, which consumes a lot of energy and may damage the texture of the intestinal casing; 4. Poor storage stability; coatings containing active ingredients are prone to performance degradation during storage. 5. Limited printing adaptability, making it difficult to simultaneously meet the stable printing requirements of multiple processes such as digital inkjet, flexographic, and gravure printing.

[0004] Therefore, developing a green, safe, mildly cross-linked, firmly bonded pattern, stable in storage, and widely adaptable to printing edible paint has significant market value. Summary of the Invention

[0005] The purpose of this invention is to provide an edible enzyme-crosslinked paint, its preparation method, and its application, so as to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: An edible enzyme crosslinking paint, by weight percentage, comprises the following components: 4-10% edible binder, 0.1-3% bio-crosslinking enzyme, 1-6% microcapsule natural pigment, 1-5% enzyme activator, 0.1-1% rheology modifier, 1-5% plasticizer, and the balance being solvent; The biocrosslinking enzyme includes one or more combinations of glutamine transaminase, laccase, tyrosinase, polyphenol oxidase, peroxidase, and lysine oxidase.

[0007] Preferably, the edible binder includes one or more combinations of edible gelatin, hydrolyzed gelatin, sodium caseinate, pea protein, soy protein isolate, whey protein, hydrolyzed whey protein, sunflower seed protein, potato protein, and silk peptide protein.

[0008] Preferably, the enzyme activation aid includes one or more combinations of trehalose, sucrose, erythritol, fructooligosaccharides, edible calcium salts, edible magnesium salts, edible zinc salts, betaine, taurine, vitamin C, rosemary extract, and pH buffers; wherein the pH buffer is a citric acid / citrate system.

[0009] Preferably, the microcapsule natural pigment is one or more of the following: gardenia yellow pigment, gardenia blue pigment, phycocyanin, carmine, β-carotene, plant carbon black, beet red, red yeast rice yellow pigment, and water-soluble astaxanthin, obtained through microencapsulation.

[0010] Preferably, the rheology modifier includes one or more of gellan gum, xanthan gum, carrageenan, modified starch, hydroxypropyl methylcellulose, polyethylene glycol, and microcrystalline cellulose; wherein the modified starch is one or more of acetylated distarch phosphate, hydroxypropyl distarch phosphate, hydroxypropyl starch, and octenyl succinate starch ester.

[0011] Preferably, the plasticizer comprises one or more combinations of glycerol, sorbitol, propylene glycol, xylitol, medium-chain triglycerides, and triethyl citrate; Preferably, the solvent includes deionized water, a 50-70 vol% food-grade ethanol aqueous solution, or a 5-10 vol% propylene glycol-water mixed solution.

[0012] Preferably, the coating has a viscosity of 50-200 mPa·s, a pH of 6.0-7.5, and a particle size of ≤5 μm.

[0013] This solution also provides a method for preparing the above-mentioned edible enzyme-crosslinked paint, comprising the following steps: S1. Mix the bio-crosslinking enzyme and the enzyme activation aid in a certain proportion, and freeze-dry or spray-dry to obtain the enzyme complex. S2. Dissolve the edible binder in a solvent at 40~60℃, add microcapsule natural pigments, rheology modifiers, and plasticizers, and homogenize at high speed to obtain a dispersion. S3. Add the enzyme complex obtained in step S1 to the dispersion in step (2), stir gently at a temperature below 30°C, adjust the pH and viscosity, filter and degas under vacuum to obtain the finished coating.

[0014] Preferably, in step S1, the freeze-drying temperature is ≤-40℃ and the vacuum degree is ≤20Pa; the spray drying inlet air temperature is 80~120℃ and the outlet air temperature is 40~60℃.

[0015] Preferably, in step S2, the high-speed homogenization speed is 8000~15000 rpm, and the time is 3~10 minutes.

[0016] Preferably, in step S3, the pH is adjusted to 6.0~7.5, and the product is filtered through a 200-400 mesh sieve, resulting in a finished coating with a viscosity of 50-200 mPa·s.

[0017] This solution also provides an application of edible enzyme cross-linked paint on collagen casings, wherein the paint is applied to the surface of the collagen casing base tube by digital printing or transfer.

[0018] Specifically, the following steps are included: (1) Substrate pretreatment: The collagen casing base tube is leveled and dust removed to ensure that the printing surface is flat, free of static electricity and oil stains.

[0019] (2) Color printing / transfer, using any of the following methods: Method 1: Digital Printing Using on-demand inkjet (DOD) digital printing equipment, edible enzyme cross-linked color paint is directly printed onto the surface of the sausage casing base tube. The printing speed is 10-60 m / min, the ink layer thickness is 1-5 μm, and the pattern accuracy is ≥300 dpi. Method 2: Gravure / Flexographic Transfer A pre-engraved patterned printing roller is dipped in paint and transferred onto the surface of a continuously running sausage casing base tube. The ink application rate is controlled at 1–4 g / m², and the transfer pressure is 0.1–0.3 MPa to ensure that the pattern is clear and complete.

[0020] (3) Enzymatic cross-linking curing: After printing / transfer, the material enters the curing zone and is treated for 1 to 5 minutes at 35 to 65°C and 40% to 60% relative humidity, so that the bio-cross-linking enzyme in the coating catalyzes the linker to form covalent bonds with the collagen in the casing, thus completing the curing.

[0021] (4) Sandwich structure reinforcement (optional, to improve resistance to boiling): A layer of 1% to 3% collagen liquid is evenly coated on the surface of the printed pattern. After coagulation and drying, a sandwich structure is formed, embedding the pattern between the two layers of collagen, which further improves the resistance to friction, boiling, and migration.

[0022] (5) Drying and shaping: Dry at a low temperature of 40-60℃, and control the final moisture content to 8%-12% to make the coating fully form a film and not sticky.

[0023] (6) Cooling and rolling: After cooling to room temperature, roll up to obtain a finished collagen casing with colored patterns that is edible, resistant to steaming and boiling, does not fade, and does not migrate.

[0024] The beneficial effects of the above-described technical solution of the present invention are as follows: 1. High safety: It uses food-grade enzymes for cross-linking without introducing chemical cross-linking agents. The enzymes can be deactivated by heating after the reaction, leaving no toxic residues and meeting food safety standards and clean label requirements.

[0025] 2. Mild cross-linking conditions: reaction temperature 35–65℃, near-neutral pH, low energy consumption, and does not damage the natural texture of the casing.

[0026] 3. High pattern bonding strength: Enzymatic reaction forms covalent bonds between the coating binder and the collagen molecules of the casing, increasing adhesion by more than 30% compared to traditional physical adsorption.

[0027] 4. Excellent processing resistance: After boiling in water at 90℃ for 60 minutes, the color difference ΔE of the pattern is ≤1.5 and the pigment migration rate is ≤0.3%. After smoking, the color difference ΔE of the pattern is ≤2.0.

[0028] 5. Good storage stability: After pretreatment with an enzyme activity protectant, the coating retains ≥85% of its enzyme activity after 30 days of storage at 4°C.

[0029] 6. Excellent printability: The viscosity and surface tension are adjustable, making it suitable for various printing processes such as digital inkjet, gravure / flexographic transfer. Attached Figure Description

[0030] The above and other objects, features, and advantages of exemplary embodiments of the present invention will become readily apparent upon reading the following detailed description with reference to the accompanying drawings. In the drawings, several embodiments of the invention are illustrated by way of example and not limitation, and like or corresponding reference numerals denote like or corresponding parts, wherein: Figure 1 This is a schematic diagram of the product of the present invention. Detailed Implementation

[0031] The following embodiments are provided to better understand the present invention and are not limited to the preferred embodiments described. They do not constitute a limitation on the content and scope of protection of the present invention. Any product that is the same as or similar to the present invention, derived by any person under the guidance of the present invention or by combining the features of the present invention with other prior art, falls within the protection scope of the present invention.

[0032] Where specific experimental steps or conditions are not specified in the examples, they can be performed according to the conventional experimental steps or conditions described in the literature in this field. Reagents or instruments whose manufacturers are not specified are all commercially available conventional instruments or reagent products, and the reagents are edible. Example 1

[0033] An edible enzyme-crosslinked paint, comprising the following components by weight percentage: hydrolyzed gelatin (Gelken hydrolyzed gelatin, Xiamen Gelken Gelatin Co., Ltd.) 3%, sodium caseinate (BR grade, Shanghai Maclean Biochemical) 2.5%, transglutaminase (Dongju TG-10, Jiangsu Dongju Biotechnology) 0.4%, laccase (Songguan LAC-10000, Nanjing Songguan Biotechnology) 0.3%, microencapsulated gardenia yellow pigment (E60, Henan Zhongda Hengyuan) 1.5%, and trehalose (food grade, Shandong). The ingredients are: 1.2% Fuyang Biotechnology, 0.3% calcium chloride (food grade, Shandong Haihua Group), 0.5% betaine (food grade, Shandong Qilu Biotechnology), 0.15% xanthan gum (food grade, Hebei Xinhe Biotechnology), 0.2% modified starch (hydroxypropyl starch phosphate, Shandong Fuyang Biotechnology), 1.5% glycerol (food grade 99.5%, Zhejiang Hengyi), and 1.0% sorbitol (SOR-70, Shandong Tianli). The balance is a 5% (v / v) mixture of deionized water and propylene glycol (PG-99, Shandong Luxi).

[0034] The above coatings are prepared using the following method: A bio-crosslinking enzyme was mixed with an enzyme activation aid and freeze-dried at -45°C and 10 Pa for 24 hours to prepare an enzyme complex. Edible binders were dissolved in a solvent at 50°C with stirring. Microcapsule natural pigments, rheology modifiers, and plasticizers were added sequentially, and the mixture was homogenized at 10,000 rpm for 5 minutes to obtain a dispersion. The dispersion was cooled to 28°C, and the enzyme complex was added, gently stirred for 10 minutes. The pH was adjusted to 6.5, water was added to the predetermined total volume, filtered through a 300-mesh sieve, and degassed under vacuum to obtain the coating.

[0035] Performance testing: After the coating was sealed and stored at 4℃ for 30 days, the enzyme activity retention rate was 90%; the coating peel strength was 2.1 N / cm; after boiling in water at 90℃ for 60 minutes, there was no dissolution or peeling, the color difference ΔE=1.42, and the pigment migration rate was 0.26%. Example 2

[0036] An edible enzyme-crosslinked paint, by weight percentage, comprises the following components: 5% hydrolyzed whey protein (Lacprodan® Hydro.PowerPro), 0.3% peroxidase (LP-001, Jiangsu Huace Biotechnology), 1.5% phycocyanin microcapsules (E18, Zhejiang Binmei Biotechnology), 1.0% erythritol (Type A, Shandong Sanyuan Biotechnology), 0.4% magnesium chloride (food grade, Jiangsu Kelunduo), 0.6% taurine (FT-001, Huatang Jurui), 0.25% hydroxypropyl methylcellulose (AnxinCel® F50), 2.0% medium-chain triglycerides (food grade, Indonesia Domex), and the balance being deionized water.

[0037] The above coatings are prepared using the following method: A bio-crosslinking enzyme was mixed with an enzyme activation aid and spray-dried at an inlet air temperature of 90°C and an outlet air temperature of 50°C to prepare an enzyme complex. Edible binders were dissolved in deionized water at 45°C, and microcapsule natural pigments, rheology modifiers, and plasticizers were added. The mixture was homogenized at 12,000 rpm for 4 minutes to obtain a dispersion. The dispersion was cooled to 25°C, and the enzyme complex was added. The mixture was gently stirred for 15 minutes, the pH was adjusted to 6.0, and water was added to the predetermined total volume. The mixture was filtered through a 300-mesh sieve and degassed under vacuum to obtain the final product.

[0038] Performance testing: After storing the coating at 4℃ for 30 days, the enzyme activity retention rate is 87%; the pattern is resistant to smoke (65–70℃ / 30min, ΔE=2.0), the coating peel strength is 1.9N / cm, and it is compatible with digital printing and digital inkjet printing without clogging. Comparative Example

[0039] The difference between it and Example 1 is that, By weight percentage, it comprises the following components: 6% edible gelatin, 2% gardenia yellow pigment, 0.3% gellan gum, 3% glycerin, and the balance being deionized water.

[0040] Mix and dissolve using conventional methods, then dry and cure at 55°C.

[0041] Performance: Coating peel strength 1.3 N / cm, partially peeled off after boiling in water at 90℃ for 30 minutes, color difference ΔE=4.2, obvious pigment migration.

[0042] In the test methods of the above embodiments and comparative examples, the enzyme activity retention rate was determined according to the "Detection Method for Glutamine Transaminase Activity" (GB / T34795-2017); the peel strength was determined according to the "Test Method for Peel Strength of Adhesives - Flexible Materials to Flexible Materials" (GB / T2791-1995); and the color difference was measured using a colorimeter.

[0043] This invention utilizes a bio-crosslinking enzyme to catalyze the formation of covalent bonds between the binder and the casing substrate, fundamentally overcoming the shortcomings of traditional physically adsorbed coatings (such as the comparative example) which exhibit weak adhesion and easy detachment. The application of this coating on collagen casings is as follows: Figure 1 As shown in the data, the comparative example showed peeling and pigment migration after boiling in water at 90℃ for 30 minutes; while in Example 1, the pattern remained intact after boiling in water at 90℃ for 60 minutes, with a color difference ΔE as low as 1.42, a pigment migration rate ≤0.3%, and a peel strength of 2.1 N / cm, which is more than 30% higher than the traditional process. In addition, by introducing enzyme activating agents and microencapsulated pigments, the enzyme activity retention rate of the coating is still not less than 85% after being stored at 4℃ for 30 days, and it is compatible with modern printing processes such as digital inkjet.

[0044] This invention is not only non-toxic and residue-free, in line with the trend of clean labeling, but also achieves a perfect combination of food safety and excellent processing performance, possessing extremely high industrialization value.

[0045] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Any other modifications or equivalent substitutions made by those skilled in the art to the technical solutions of the present invention, as long as they do not depart from the spirit and scope of the technical solutions of the present invention, should be covered within the scope of the claims of the present invention.

Claims

1. An edible enzyme-crosslinked paint, characterized in that, By weight percentage, it comprises the following components: 4-10% edible binder, 0.1-3% bio-crosslinking enzyme, 1-6% microencapsulated natural pigment, 1-5% enzyme activation aid, 0.1-1% rheology modifier, 1-5% plasticizer, and the balance being solvent; The biocrosslinking enzyme includes one or more combinations of glutamine transaminase, laccase, tyrosinase, polyphenol oxidase, peroxidase, and lysine oxidase.

2. The edible enzyme-crosslinked paint according to claim 1, characterized in that, The edible binder includes one or more combinations of edible gelatin, hydrolyzed gelatin, sodium caseinate, pea protein, soy protein isolate, whey protein, hydrolyzed whey protein, sunflower seed protein, potato protein, and silk peptide protein.

3. The edible enzyme-crosslinked colored paint according to claim 1, characterized in that, The enzyme activation aids include one or more combinations of trehalose, sucrose, erythritol, fructooligosaccharides, edible calcium salts, edible magnesium salts, edible zinc salts, betaine, taurine, vitamin C, rosemary extract, and pH buffers.

4. The edible enzyme-crosslinked colored paint according to claim 1, characterized in that, The microcapsule natural pigments are one or more of the following: gardenia yellow pigment, gardenia blue pigment, phycocyanin, carmine, β-carotene, plant carbon black, beet red, red yeast rice yellow pigment, and water-soluble astaxanthin, obtained through microencapsulation.

5. The edible enzyme-crosslinked colored paint according to claim 1, characterized in that, The rheology modifier includes one or more combinations of gellan gum, xanthan gum, carrageenan, modified starch, hydroxypropyl methylcellulose, polyethylene glycol, and microcrystalline cellulose; the plasticizer includes one or more combinations of glycerol, sorbitol, propylene glycol, xylitol, medium-chain triglycerides, and triethyl citrate; the solvent includes deionized water, a 50%–70% (v / v) water solution of food-grade ethanol, or a 5%–10% (v / v) water solution of propylene glycol.

6. The edible enzyme-crosslinked colored paint according to claim 1, characterized in that, The coating has a viscosity of 50-200 mPa·s, a pH of 6.0-7.5, and a particle size of ≤5 μm.

7. A method for preparing an edible enzyme-crosslinked colored paint as described in any one of claims 1-6, characterized in that, Includes the following steps: S1. Mix the bio-crosslinking enzyme and the enzyme activation aid in a certain proportion, and freeze-dry or spray-dry to obtain the enzyme complex. S2. Dissolve the edible binder in a solvent at 40~60℃, add microcapsule natural pigments, rheology modifiers, and plasticizers, and homogenize at high speed to obtain a dispersion. S3. Add the enzyme complex obtained in step S1 to the dispersion in step (2), stir gently at a temperature below 30°C, adjust the pH and viscosity, filter and degas under vacuum to obtain the finished coating.

8. The preparation method according to claim 7, characterized in that, In step S1, the freeze-drying temperature is ≤-40℃ and the vacuum degree is ≤20Pa; the spray drying inlet air temperature is 80~120℃ and the outlet air temperature is 40~60℃.

9. The preparation method according to claim 7, characterized in that, In step S2, the high-speed homogenization speed is 8000~15000rpm and the time is 3~10 minutes; in step S3, the pH is adjusted to 6.0~7.5, filtered through a 200-400 mesh sieve, and the viscosity of the resulting finished coating is 50-200mPa・s.

10. The application of an edible enzyme-crosslinked paint as described in any one of claims 1-6 on collagen casings, characterized in that, The coating is applied to the surface of the collagen casing tubing via digital printing or transfer.

Images