An edible composite coating material, its preparation method and application

Abstract

This invention provides an edible composite coating material, its preparation method, and its application, belonging to the technical field of coating materials. The method includes the following steps: mixing chitosan, gelatin, and a solvent to obtain a gelatin-chitosan-based film solution; mixing *Cyclocarya paliurus* flavonoids, glycerol, and an ethanol solution to obtain a *Cyclocarya paliurus* flavonoid solution; mixing the gelatin-chitosan-based film solution and the *Cyclocarya paliurus* flavonoid solution to obtain a gelatin-chitosan-*Cyclocarya paliurus* flavonoid film solution; and forming the gelatin-chitosan-*Cyclocarya paliurus* flavonoid film solution into a film to obtain the edible composite coating material. The film prepared by this invention possesses good mechanical properties, antioxidant activity, and antibacterial properties, effectively preserving chilled beef, inhibiting the growth of microorganisms during storage, and extending its shelf life.

Description

Technical Field

[0001] This invention relates to the field of coating materials technology, and in particular to an edible composite coating material, its preparation method, and its application. Background Technology

[0002] In recent years, with the development of science, edible coating preservation technology has gradually become a research hotspot in the field of food preservation. As a green and novel preservation technology, edible films reduce production costs and waste of packaging materials compared to plastic packaging. They are biodegradable and do not cause environmental pollution, meeting people's current demand for environmental protection. Current edible coating technologies typically use one or more of the following three film-forming matrices: polysaccharides, proteins, and lipids. After dissolving, these matrices are sprayed or soaked onto the food, or further cast into a film and then wrapped around the food surface to delay spoilage. However, the various coating matrices in edible films often only have film-forming properties and lack good antibacterial effects. They cannot fundamentally inhibit the growth of spoilage bacteria in food, only serving to isolate oxygen and moisture. Summary of the Invention

[0003] In view of this, the purpose of this invention is to provide an edible composite coating material, its preparation method, and its application. The edible composite coating material obtained by this invention has good antibacterial effect.

[0004] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0005] This invention provides a method for preparing an edible composite coating material, comprising the following steps:

[0006] Chitosan, gelatin, and solvent are mixed to obtain a gelatin-chitosan-based film solution;

[0007] The flavonoids of Eucommia ulmoides, glycerol and ethanol solution were mixed to obtain the flavonoid solution of Eucommia ulmoides;

[0008] The gelatin-chitosan-based film solution and the Eucommia ulmoides flavonoid solution were mixed to obtain the gelatin-chitosan-Eucommia ulmoides flavonoid film solution.

[0009] The gelatin-chitosan-Cyclocarya paliurus flavonoid film solution is used to form a film to obtain the edible composite coating material.

[0010] Preferably, the mixing of chitosan, gelatin, and solvent includes the following steps:

[0011] The chitosan was mixed with an acetic acid solution to obtain a chitosan solution;

[0012] The gelatin is mixed with water to obtain a gelatin solution;

[0013] The chitosan solution and the gelatin solution are mixed to obtain the gelatin-chitosan-based film solution.

[0014] Preferably, the chitosan solution has a mass concentration of 2.5%, and the gelatin solution has a mass concentration of 2.5%.

[0015] Preferably, the volume ratio of the gelatin solution to the chitosan solution is 4:1.

[0016] Preferably, the volume percentage of glycerol in the Cyclocarya paliurus flavonoid solution is 10%.

[0017] Preferably, the amount of *Cyclocarya paliurus* flavonoids in the *Cyclocarya paliurus* flavonoid solution is 0.1 to 0.3% of the mass of the gelatin-chitosan-based film solution.

[0018] Preferably, the Cyclocarya paliurus flavonoids are prepared by a method comprising the following steps:

[0019] The powdered leaves of Eucommia ulmoides were soaked in ethanol solution, then subjected to ultrasonic extraction and evaporation concentration to obtain Eucommia ulmoides flavonoid extract.

[0020] The extract of Cyclocarya paliurus flavonoids was freeze-dried to obtain Cyclocarya paliurus flavonoids.

[0021] Preferably, the film formation is achieved by a casting and drying method, which includes the following steps: the gelatin-chitosan-Qingqianliu flavonoid film solution is drawn onto a sterile plate and placed in a constant temperature and humidity climate chamber for drying and equilibration in sequence. The drying temperature is 25°C, the humidity is 50%RH, and the time is 48 hours. The equilibration time is 24 hours.

[0022] The present invention also provides an edible composite coating material prepared by the preparation method described in the above technical solution.

[0023] The present invention also provides the application of the edible composite coating material described above in the field of coating preservation.

[0024] This invention provides a method for preparing an edible composite coating material, comprising the following steps: mixing chitosan, gelatin, and a solvent to obtain a gelatin-chitosan-based film solution; mixing Cyclocarya paliurus flavonoids, glycerol, and an ethanol solution to obtain a Cyclocarya paliurus flavonoid solution; mixing the gelatin-chitosan-based film solution and the Cyclocarya paliurus flavonoid solution to obtain a gelatin-chitosan-Cyclocarya paliurus flavonoid film solution; and forming the gelatin-chitosan-Cyclocarya paliurus flavonoid film solution into a film to obtain the edible composite coating material.

[0025] In this invention, chitosan is an excellent polysaccharide-type film-forming substrate obtained by de-N-acetylating chitin extracted from natural materials such as crab shells, shrimp shells, and insects. It also possesses certain antibacterial effects, and the resulting membrane structure exhibits high tensile strength, good toughness, and resistance to alkalis and organic solvents. Gelatin, a hydrolyzed product of collagen, is a low-cost protein-type film-forming matrix, typically produced from collagen in animal skin or bone through denaturation and degradation. It is odorless, tasteless, and easily absorbed and metabolized by the human body, resulting in a membrane with excellent gas barrier properties. Cyclocarya paliurus flavonoids are also used. Belonging to the category of phenolic derivatives, it has a slightly acidic pH and can coagulate or denature bacterial proteins, thereby damaging their cell walls and cell membranes, inhibiting microbial growth or causing cell death. It possesses good antibacterial properties and antioxidant activity. Adding it as an antibacterial agent to edible coatings can improve the antibacterial and antioxidant properties of the coatings to a certain extent. Furthermore, the addition of Cyclocarya paliurus flavonoids causes hydrogen bonding interactions between the membrane matrix, making the membrane more compact. Combining these three substances can compensate for the shortcomings of single membranes, such as high water solubility, poor antibacterial properties, and poor mechanical strength, thereby improving the performance of the membrane.

[0026] The present invention also provides an edible composite coating material prepared by the preparation method described above. The edible composite coating material prepared by the present invention can effectively preserve chilled beef, inhibit the growth of microorganisms during the storage of chilled beef, and extend its shelf life. Attached Figure Description

[0027] Figure 1 Results of DPPH free radical scavenging rates for different membrane groups;

[0028] Figure 2 Results of ABTS free radical scavenging rates in different membrane groups;

[0029] Figure 3 Images showing the appearance of different membrane groups during the 7-day preservation of chilled beef;

[0030] Figure 4 The graph shows the changes in volatile basic nitrogen in beef stored under different membrane conditions for 7 days.

[0031] Figure 5 The graph shows the changes in total bacterial count of different membranes during 7 days of beef preservation.

[0032] Figure 6 This is a diagram showing the bacterial colony distribution of different membrane groups on the 7th day of beef preservation. Detailed Implementation

[0033] This invention provides a method for preparing an edible composite coating material, comprising the following steps:

[0034] Chitosan, gelatin, and solvent are mixed to obtain a gelatin-chitosan-based film solution;

[0035] A solution of *Cyclocarya paliurus* flavonoids (CPF), glycerol, and ethanol was mixed to obtain a solution of *Cyclocarya paliurus* flavonoids.

[0036] The gelatin-chitosan-based film solution and the Eucommia ulmoides flavonoid solution were mixed to obtain the gelatin-chitosan-Eucommia ulmoides flavonoid film solution.

[0037] The gelatin-chitosan-Cyclocarya paliurus flavonoid film solution is used to form a film to obtain the edible composite coating material.

[0038] This invention mixes chitosan, gelatin and solvent to obtain a gelatin-chitosan-based film solution.

[0039] In this invention, the mixing of chitosan, gelatin, and solvent preferably includes the following steps:

[0040] The chitosan was mixed with an acetic acid solution to obtain a chitosan solution;

[0041] The gelatin is mixed with water to obtain a gelatin solution;

[0042] The chitosan solution and the gelatin solution are mixed to obtain the gelatin-chitosan-based film solution.

[0043] In this invention, the mass concentration of the chitosan solution is preferably 2.5%.

[0044] In this invention, the volume concentration of the acetic acid solution is preferably 1%.

[0045] In this invention, the mixing of chitosan and acetic acid solution is preferably carried out by magnetic stirring, and the magnetic stirring time is preferably 30 minutes.

[0046] In this invention, the mass concentration of the gelatin solution is preferably 2.5%.

[0047] In this invention, the water is preferably distilled water.

[0048] In this invention, the gelatin and water are preferably mixed by heating in a water bath and stirring, and the water bath heating temperature is preferably 70°C and the time is preferably 30 minutes.

[0049] In this invention, the preferred volume ratio of the gelatin solution to the chitosan solution is 4:1.

[0050] In this invention, the chitosan solution and gelatin solution are preferably mixed by magnetic stirring, and the magnetic stirring time is preferably 30 minutes.

[0051] This invention involves mixing Cyclocarya paliurus flavonoids, glycerol, and an ethanol solution to obtain a Cyclocarya paliurus flavonoid solution.

[0052] In this invention, the volume percentage of glycerol in the Cyclocarya paliurus flavonoid solution is preferably 10%.

[0053] In this invention, the volume percentage of ethanol in the Cyclocarya paliurus flavonoid solution is preferably 90%.

[0054] In this invention, the mixing is preferably ultrasonic, and the ultrasonic time is preferably 10 minutes.

[0055] In this invention, the volume concentration of the ethanol solution is preferably 50-90%.

[0056] In this invention, the Cyclocarya paliurus flavonoids are preferably prepared by a method comprising the following steps:

[0057] The powdered leaves of Eucommia ulmoides were soaked in ethanol solution, then subjected to ultrasonic extraction and evaporation concentration to obtain Eucommia ulmoides flavonoid extract.

[0058] The extract of Cyclocarya paliurus flavonoids was freeze-dried to obtain Cyclocarya paliurus flavonoids.

[0059] The present invention preferably obtains the *Cyclocarya paliurus* leaf powder by harvesting, drying, crushing, and sieving. The present invention does not impose any particular limitation on the specific methods of harvesting, drying, crushing, and sieving; any method well-known to those skilled in the art can be used.

[0060] In this invention, the volume concentration of the ethanol solution is preferably 50-90%.

[0061] The present invention does not impose any particular limitation on the specific methods of soaking, ultrasonic extraction, evaporation concentration and freeze drying, and any method known to those skilled in the art can be used. In the present invention, the temperature of ultrasonic extraction is preferably 25°C.

[0062] After obtaining the gelatin-chitosan-based film solution and the Eucommia ulmoides flavonoid solution, the present invention mixes the gelatin-chitosan-Eucommia ulmoides flavonoid solution to obtain the gelatin-chitosan-Eucommia ulmoides flavonoid film solution.

[0063] In this invention, the amount of *Cyclocarya paliurus* flavonoids in the *Cyclocarya paliurus* flavonoid solution is preferably 0.1-0.3% of the mass of the gelatin-chitosan-based film solution, more preferably 0.1%, 0.2%, or 0.3%.

[0064] In this invention, the mixing is preferably performed by sequentially performing magnetic stirring and ultrasonic defoaming, the magnetic stirring time is preferably 10 min, and the ultrasonic defoaming time is preferably 30 min.

[0065] After obtaining the gelatin-chitosan-Cyclocarya paliurus flavonoid film solution, the present invention forms the gelatin-chitosan-Cyclocarya paliurus flavonoid film solution into a film to obtain the edible composite coating material.

[0066] In this invention, the film formation is preferably achieved by casting and drying, which preferably includes the following steps: the gelatin-chitosan-Qingqianliu flavonoid film solution is drawn onto a sterile plate and placed in a constant temperature and humidity climate chamber for drying and equilibration in sequence. The drying temperature is 25°C, the humidity is 50%RH, and the time is 48h. The equilibration time is 24h.

[0067] In this invention, the process of drying and balancing preferably includes removing the film.

[0068] In this invention, it is preferable to flip the object during the balancing process.

[0069] The present invention also provides an edible composite coating material (G-CS-CPF composite film) prepared by the preparation method described above.

[0070] The present invention also provides the application of the edible composite coating material described above in the field of coating preservation.

[0071] The present invention does not impose any special limitation on the specific method of application, and any method known to those skilled in the art can be used.

[0072] To further illustrate the present invention, the edible composite coating material, its preparation method, and its application provided by the present invention are described in detail below with reference to examples, but these should not be construed as limiting the scope of protection of the present invention.

[0073] The preparation method of Cyclocarya paliurus flavonoids used in the embodiments of the present invention is as follows:

[0074] The leaves of *Cyclocarya paliurus* are obtained by picking, drying, crushing and sieving. After soaking in ethanol, ultrasonic extraction and evaporation concentration, *Cyclocarya paliurus* flavonoid extract is obtained. After freeze-drying, *Cyclocarya paliurus* flavonoids are obtained.

[0075] Example 1

[0076] (1) Weigh out chitosan and dissolve it in a 1% acetic acid solution. Stir the solution magnetically at 25°C for 30 minutes to obtain a chitosan solution with a chitosan concentration of 2.5%.

[0077] Weigh out gelatin and dissolve it in water. Stir in a water bath at 70°C for 30 minutes to obtain a gelatin solution with a mass concentration of 2.5%. Slowly pour the gelatin solution and chitosan solution together at a volume ratio of 4:1 and stir magnetically for 30 minutes to obtain a gelatin-chitosan-based film solution.

[0078] (2) Weigh 0.1% of the mass of the gelatin-chitosan-based film solution and dissolve it in 50 vol% ethanol solution. Add 10% glycerol as a plasticizer and sonicate for 10 min to obtain the gelatin-chitosan-based film solution. The ratio of the amount of gelatin-chitosan-based film solution, ethanol solution and glycerol is 0.005 g: 5 mL: 0.5 g. Then slowly add the gelatin-chitosan-based film solution to the gelatin-chitosan-based film solution and sonicate for 30 min to obtain the gelatin-chitosan-gelatin-chitosan-based film solution.

[0079] (3) Preparation of edible gelatin-chitosan-Cyclocarya paliurus flavonoid film using casting and drying method:

[0080] Take 15 mL of the blended membrane solution from step (2) into a disposable sterile culture dish, uncover the culture dish and place it in a constant temperature and humidity climate chamber to dry for 48 h at a temperature of 25 °C and a humidity of 50% RH; after drying, turn it over and equilibrate for 24 h to obtain a gelatin-chitosan-0.1% Eucommia ulmoides flavonoid edible membrane (denoted as G-CS-0.1% CPF membrane, gelatin-chitosan 0.1% CPF group).

[0081] Example 2

[0082] Same as in Example 1, except that 0.2% of the mass of the gelatin-chitosan-based film liquid was weighed as Eucommia ulmoides flavonoid powder to obtain a gelatin-chitosan-0.2% Eucommia ulmoides flavonoid edible film (denoted as G-CS-0.2% CPF film, gelatin-chitosan 0.2% CPF group).

[0083] Example 3

[0084] Same as in Example 1, except that 0.3% of the mass of the gelatin-chitosan-based film liquid was weighed as Eucommia ulmoides flavonoid powder to obtain a gelatin-chitosan-0.3% Eucommia ulmoides flavonoid edible film (denoted as G-CS-0.3% CPF film, gelatin-chitosan 0.3% CPF group).

[0085] Comparative Example

[0086] A method for preparing a gelatin-chitosan composite coating is as follows:

[0087] (1) Chitosan was weighed and dissolved in a 1% acetic acid solution. The solution was magnetically stirred at 25°C for 30 min to obtain a chitosan solution with a chitosan concentration of 2.5%. Gelatin was weighed and dissolved in water. The solution was stirred in a water bath at 70°C for 30 min to obtain a gelatin solution with a gelatin concentration of 2.5%. The gelatin solution and chitosan solution were slowly poured together in a volume ratio of 4:1. After magnetic stirring for 30 min, glycerol was added. The volume ratio of glycerol to the gelatin-chitosan blend solution was 0.01:1. After ultrasonic treatment for 30 min, a gelatin-chitosan blend film solution was obtained.

[0088] (2) Preparation of edible gelatin-chitosan-Cyclocarya paliurus flavonoid film using casting and drying method:

[0089] Take 15 mL of the blended membrane solution from step (1) into a disposable sterile culture dish, uncover the culture dish and place it in a constant temperature and humidity climate chamber to dry for 48 h at a temperature of 25 °C and a humidity of 50% RH; after drying, turn it over and equilibrate for 24 h to obtain a gelatin-chitosan edible membrane (denoted as G-CS membrane, gelatin-chitosan group).

[0090] The mechanical properties of the edible coating prepared by this invention were measured, and the specific procedures are as follows:

[0091] The thickness of the film was measured using a thickness gauge, with each film sample measured five times. The tensile strength (TS) and elongation at break (EAB) of the film were measured using a texture analyzer. After equilibration, the film was removed and cut into strips of 35×50mm. The film samples were fixed between clamps with an initial distance of 30mm and a stretching speed of 1mm / s. Each sample was measured five times.

[0092] Table 1 shows the mechanical properties of the membrane samples prepared in Examples 1-3 and the control group. The results show that as the amount of Cyclocarya paliurus flavonoids added increases, the tensile strength of the membrane gradually increases and the elongation at break gradually decreases. This indicates that the addition of Cyclocarya paliurus flavonoids can enhance the hardness of the membrane. This is because Cyclocarya paliurus flavonoids can crosslink gelatin and chitosan together through hydrogen bonds, thereby forming a dense network structure. This is more conducive to the application of the coating in food preservation, and may block oxygen and moisture and inhibit the growth of microorganisms.

[0093] Table 1. Mechanical properties of G-CS membrane and G-CS-CPF membrane

[0094]

[0095] Note: All values ​​in the table are expressed as mean ± standard deviation; different lowercase letters indicate significant differences (P < 0.05). The antioxidant capacity of the edible coating prepared in this invention was determined, and the specific operation is as follows:

[0096] Different groups of membranes were added to 5 mL of DPPH solution (0.1 mmol / L) at concentrations of 1, 2, 3, 4, and 5 mg / mL. The membranes were incubated in the dark at room temperature for 30 minutes, and then the absorbance at 517 nm was measured using a UV-Vis spectrophotometer, with anhydrous ethanol as a blank control. The DPPH free radical scavenging rate was calculated as shown in Formula 1.

[0097]

[0098] In Formula 1: A0 is the absorbance of deionized water; A1 is the absorbance of the sample solution; A2 is the absorbance of anhydrous ethanol replacing DPPH-anhydrous ethanol solution.

[0099] A 7 mmol / L ABTS solution was prepared using 2.45 mmol / L K₂S₂O₄ solution as the solvent. The solution was allowed to stand in the dark for 16 h. The mixture was then diluted with deionized water to achieve an absorbance of 0.70 ± 0.01 at 734 nm. Different groups of membranes were added at concentrations of 1, 2, 3, 4, and 5 mg / mL. The reaction was allowed to proceed for 10 min. Deionized water was used as a blank control. The absorbance was measured at 734 nm. Each treatment was repeated three times. The ABTS free radical scavenging rate was calculated using Formula 2.

[0100]

[0101] In Formula 2: A0 is the absorbance of deionized water; A1 is the absorbance of the sample solution; A2 is the absorbance of deionized water replacing ABTS solution.

[0102] Figure 1 The results show the DPPH free radical scavenging rate. Figure 2 The results show the ABTS free radical scavenging rate. Figures 1-2 Different lowercase letters indicate significant differences (P < 0.05), indicating that the G-CS-CPF composite film has higher DPPH free radical scavenging capacity and ABTS free radical scavenging capacity (especially the G-CS-0.3%CPF film) compared with the control group. Therefore, composite coatings containing CPF may better inhibit food oxidative spoilage, thereby achieving a preservation effect.

[0103] The effect of the edible coating prepared in this invention on the preservation of beef was investigated. The specific procedures are as follows:

[0104] Different groups of films were wrapped around fresh beef (5 hours post-slaughter) with sides of 2.5cm × 2.5cm × 2.5cm for preservation. The beef was stored at 4℃ for 7 days, and volatile basic nitrogen and total bacterial count were determined every 24 hours. Volatile basic nitrogen was determined using the micro-diffusion method. 10g of meat sample was weighed, chopped, and mixed thoroughly. 100mL of distilled water was added, and the mixture was shaken, allowed to stand for 30 minutes, and then filtered. 1mL of boric acid absorption solution and one drop of mixed indicator solution were added to the center of the diffusion dish. 1mL of sample solution and 1mL of saturated potassium carbonate were added to each side of the outside of the dish. The dish was covered and reacted at 37℃ for 2 hours. The solution was then titrated with 0.1mol / L hydrochloric acid to the endpoint. The volatile basic nitrogen content was calculated using Formula 3.

[0105]

[0106] In formula 3:

[0107] V1 - The volume of hydrochloric acid or sulfuric acid standard titration solution consumed by the sample, in milliliters (mL);

[0108] V2 - The volume of standard hydrochloric acid or sulfuric acid solution consumed by the blank sample, in milliliters (mL);

[0109] c1 - The concentration of the standard titration solution of hydrochloric acid or sulfuric acid, expressed in moles per liter (mol / L);

[0110] m1 - Sample mass, in grams (g).

[0111] Figure 3 Images showing the appearance of different membrane groups on chilled beef within 7 days of preservation. Figure 4 The graph shows the changes in volatile basic nitrogen (TVB-N) of beef treated with different membranes over 7 days of preservation. It reveals that the TVB-N value of the group treated with the G-CS-CPF composite membrane was significantly lower than that of the control group. The TVB-N value of the G-CS-0.3% CPF group remained below 15 mg / 100g on day 5, classifying it as Grade 1 freshness, and remained below 25 mg / 100g after 7 days of storage, classifying it as Grade 2 freshness. This is because the G-CS-CPF composite membrane possesses certain moisture-barrier and oxygen-barrier functions, and CPF itself has antibacterial properties, inhibiting bacterial growth and thus slowing down the decomposition of proteins and amino acids.

[0112] The method for determining the total bacterial count is as follows: Weigh 10g of meat sample into a sterile homogenizing bag and add 90mL of sterile physiological saline for homogenization. Homogenize each sample for 2 minutes. Dilute the homogenate 10-fold, and pre-add 1mL of bacterial suspension to three appropriate gradients. Pour the diluted solutions onto plates and incubate at 37℃ for 24 hours. Count the colonies. The results are shown in the figure. Figures 5-6 , Figure 5 This graph shows the changes in total bacterial count of different membrane groups during 7 days of beef preservation. Figure 6 The images show the colony distribution of different film groups on the 7th day of beef preservation. The results indicate that the film containing added Eucommia ulmoides flavonoids can better inhibit the growth of microorganisms in beef. The TVC of the G-CS-0.3% CPF treatment group was still below 6.0 logCFU / g on the 7th day, indicating secondary freshness. This is because the addition of CPF enhances the barrier and antibacterial properties of the composite coating.

[0113] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing an edible composite coating material, characterized by, The method comprises the following steps: The chitosan, gelatin and solvent are mixed to obtain a gelatin-chitosan-based film solution; the mixing of the chitosan, gelatin and solvent comprises the following steps: the chitosan is mixed with an acetic acid solution to obtain a chitosan solution; the gelatin is mixed with water to obtain a gelatin solution; and the chitosan solution and the gelatin solution are mixed to obtain the gelatin-chitosan-based film solution; The mass concentration of the chitosan solution is 2.5%, and the mass concentration of the gelatin solution is 2.5%; the volume ratio of the gelatin solution to the chitosan solution is 4:1; The cyclocarya paliurus flavones, glycerol and ethanol solution are mixed to obtain a cyclocarya paliurus flavone solution; The gelatin-chitosan-based film solution and the cyclocarya paliurus flavone solution are mixed to obtain a gelatin-chitosan-cyclocarya paliurus flavone film solution; the amount of the cyclocarya paliurus flavones in the cyclocarya paliurus flavone solution is 0.3% of the mass of the gelatin-chitosan-based film solution; The gelatin-chitosan-cyclocarya paliurus flavone film solution is formed into a film to obtain the edible composite coating material.

2. The production method according to claim 1, characterized by, The volume percentage content of glycerol in the cyclocarya paliurus flavone solution is 10%.

3. The preparation method according to claim 1, characterized in that, The cyclocarya paliurus flavones are prepared by a method comprising the following steps: The cyclocarya paliurus leaf powder and an ethanol solution are sequentially soaked, ultrasonically extracted and evaporated and concentrated to obtain a cyclocarya paliurus flavone extract; The cyclocarya paliurus flavone extract is freeze-dried to obtain the cyclocarya paliurus flavones.

4. The method of claim 1, wherein, The film formation is a casting drying method film formation, which comprises the following steps: the gelatin-chitosan-cyclocarya paliurus flavone film solution is sucked onto a sterile plate, and is sequentially dried and balanced in a constant-temperature and constant-humidity climate box; the temperature of the drying is 25℃, the humidity is 50% RH, and the time is 48h; and the time of the balancing is 24h.

5. The edible composite coating material prepared by the preparation method in any one of claims 1-4.

6. The application of the edible composite coating material in claim 5 in the field of film coating preservation.

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