Compound polysaccharide edible film containing probiotics and preparation method thereof

Abstract

The invention discloses a compound polysaccharide edible film containing probiotics and a preparation method of the compound polysaccharide edible film. The compound polysaccharide edible film comprises a compound premna microphylla pectin polysaccharide film-forming solution, a probiotic cell suspension and a denatured whey protein isolate. The composite premna microphylla pectin polysaccharide film-forming solution and the probiotic cell suspension are subjected to emulsification microcapsule pretreatment and film forming preparation, and the probiotic-containing composite polysaccharide edible film is obtained. The preservative not only can be used as a carrier of probiotics, but also can improve the safety and protect the sense and nutritional quality of coated fruits and vegetables. The edible coating film forms a barrier of water vapor, oxygen and carbon dioxide, so that the respiration of the fruits and vegetables is reduced, a high-humidity environment is provided, and the shelf life of the fruits and vegetables is prolonged. In addition, the edible coating film can relieve physical damage to fruits and vegetables caused by impact, pressure or vibration.

Description

Technical Field

[0001] The invention relates to the technical field of edible packaging materials, and in particular to an edible composite polysaccharide film containing probiotics and a preparation method thereof. Background Art

[0002] Edible films are degradable materials and are considered to be active packaging. These types of packaging, in addition to physical protection, moisture and gas suppression, can also serve as carriers for various active compounds, such as antimicrobial agents and antioxidants. Premna microphylla Turcz Pectic polysaccharides (PPPs) are obtained from the medicinal and edible plant Turcz, which is a high-methoxyl pectin with strong emulsifying and antioxidant properties. The consumption of Turcz is based on the folk use of its tender leaves and paper strips to make gel jelly, also known as "fairy tofu", which reflects the rich pectin content in Turcz and its good pectin properties, so it can be used in pharmaceutical and food applications. Sodium alginate (SAA) has become an ideal choice for biodegradable and biocompatible materials due to its wide range of sources, low cost, excellent safety and excellent film-forming properties, providing unique advantages for the development of antimicrobial edible films.

[0003] Edible films have recently been used as effective carriers for the delivery of various bioactive compounds in food systems. Probiotics are living microorganisms that, when ingested in adequate amounts (at least 10 6 Up to 10 7 CFU / g), can provide health benefits to consumers. The health benefits of probiotics are mainly due to their inhibitory effects on harmful intestinal flora, enhancing the human immune system, lowering blood pressure, and reducing serum cholesterol levels. One way to add sufficient amounts of probiotics to the human body is to add them to films as a new type of bioactive packaging, thereby providing good stability. In addition, the presence of probiotics in edible films reduces the growth of spoilage microorganisms and improves the health of consumers. Because fruits and vegetables are eaten fresh, the use of edible films containing probiotics can be used as a means to control spoilage and deliver these beneficial bacteria to the body. Studies have shown that the cellulose in fruits can protect probiotics as they pass through the intestines; therefore, it has a protective effect on the integrity of probiotics and delivers them to the colon. In recent years, the use of edible coatings containing probiotics in the preservation of fresh fruits has received a lot of attention because they help maintain physicochemical parameters, nutritional factors and sensory qualities during storage.

[0004] Chinese patent CN 115399481 A discloses a functionalized edible film loaded with probiotics and a preparation method thereof. The edible film is based on a biopolymer and filled with probiotic liposomes protected by protamine aggregates. Active probiotics are encapsulated by liposomes, giving them a slow-release function. The surface of the liposomes is modified by β-cholesterol-D-glucoside (β-CG), which can cooperate with zwitterionic lipids to induce protamine to form spherical fiber aggregates around the liposomes through hydrogen bonding. The diameter of the protamine fiber aggregates is 10-30um. Protamine itself has a high thermal stability. The fiber aggregates formed by this protein form a stable carrier protection around the liposomes, thereby improving the thermal stability of the probiotic active substances. This type of probiotic film still has certain application deficiencies. In addition to improving the survival rate of probiotics, we should also pay attention to the negative effects of probiotics on fruits and vegetables. This is because active probiotics wrapped in edible films usually continue to produce organic acids or other metabolites over time, which may affect the sensory characteristics of fruits and vegetables, causing the color of fruits and vegetables to darken, etc. In addition, natural antibacterial active substances (fish protein has a special smell) should not affect the sensory quality of fruit and vegetable products. Summary of the invention

[0005] The object of the present invention is to provide a composite polysaccharide edible film containing probiotics and a preparation method thereof, so as to solve the technical problem that the edible film in the prior art affects the sensory characteristics of fruits and vegetables.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] The invention provides a composite polysaccharide edible film containing probiotics. The composite polysaccharide edible film comprises a composite tofu taro pectin polysaccharide film-forming solution, a probiotic cell suspension and a denatured whey protein isolate.

[0008] The present invention also provides a method for preparing a composite polysaccharide edible film containing probiotics, comprising the following steps:

[0009] ① Emulsified microencapsulation process (pretreatment): The composite tofu pectin polysaccharide film-forming solution (Solution A) is mixed with 10 mL of concentrated probiotic cell suspension (Solution B), and then 8% (m / v) denatured whey protein isolate is added to obtain a final concentration of 2% composite polysaccharide edible film. Microcrystalline calcium carbonate is added to the mixture (1.4 mmol), and after homogenization, the mixture film liquid is dispersed into vegetable oil (sunflower oil, etc.) containing 1% Span 80 (membrane liquid: vegetable oil = 6:4, v / v) using an electric stirrer (600 rpm). After 15 minutes of emulsification, 8.7 mmol of glacial acetic acid is added using a 1 mL syringe and syringe driver (flow rate is 0.05 mL min –1). Stir continuously for 15 min to dissolve the calcium carbonate. Use 0.05 M calcium chloride (CaCl 2 ) for microcapsule embedding treatment. When the microcapsules are stabilized, the top lipid phase is removed by suction with a vacuum pump, and the residual oil is removed by washing with a 0.05M calcium chloride solution and a 0.9% sodium chloride solution containing 1% Tween 80, thereby obtaining an emulsified microencapsulated edible membrane liquid.

[0010] ② Film preparation process: The emulsified microencapsulated edible film liquid was ultrasonically treated for 8 to 10 minutes for degassing and defoaming, and then the density of 0.3 g / cm 2 ~0.34g / cm 2 The degassed edible film liquid is evenly spread on the surface of the polypropylene plate and dried at 30-35° C. for 5-7 hours to obtain a composite polysaccharide edible film containing probiotics.

[0011] Furthermore, the tofu chai pectin polysaccharide is prepared by the following steps:

[0012] Preparation of tofu taro pectin: Weigh 10.0g tofu taro leaf powder (dry basis) and add pH 5 buffer solution (adjusted with 1% citric acid and 1% sodium bicarbonate, the optimal pH for cellulase) at a material-liquid ratio of 1:10 (w / v), stir evenly, and then treat with dielectric barrier discharge plasma. The detailed parameters of the dielectric barrier discharge plasma device in the test are: plate spacing 30mm, high-voltage discharge voltage 130kV, high-voltage discharge frequency 50Hz, discharge duration 60s, discharge gap time 10s, and the number of discharges is set according to the test needs. The treated mixed solution was then added with 2400U / g of cellulase, the final solid-liquid ratio was adjusted to 1:40, the enzymatic hydrolysis time was 1h, and the mixture was placed in a shaking incubator for enzymatic hydrolysis; the enzymatic hydrolysis system was inactivated at 90°C for 15min, and after cooling, it was centrifuged at 5000r / min for 10min; the enzymatic hydrolyzate was precipitated with twice the volume of anhydrous ethanol, allowed to stand for alcohol precipitation for 12h, the precipitate was re-dissolved in water, and the ethanol was removed by vacuum distillation, and the crude pectin was obtained by freeze-drying.

[0013] The crude pectin of tofu shiitake was dissolved in distilled water, and the protein and other impurities in the crude pectin of tofu shiitake were removed by Sevage method (polysaccharide solution: chloroform: isoamyl alcohol = 25:4:1, v / v / v) deproteinization 5 times), and then the tofu shiitake pectin was precipitated with anhydrous ethanol and freeze-dried. The pectin after protein removal was prepared into a 10 mg / mL solution, passed through a 0.45 μm filter membrane, and purified by a cellulose DEAE-52 column (2.6 cm × 30 cm), and balanced with 0, 0.1, 0.3, 0.5 M sodium chloride phosphate buffer (0.02 mol / L, pH = 6.8). Then the eluate was collected, measured by phenol-sulfuric acid method with α-glucose as the standard, and the elution curve was drawn. It was further purified using Sephadex G-150 column (2.6 cm × 100 cm), and freeze-dried to obtain pure tofu shiitake pectin polysaccharide.

[0014] Furthermore, the composite tofu-wood pectin polysaccharide film-forming solution is prepared by the following steps:

[0015] According to the ratio of PPPs:SAA = 30:70 (m / m) (this is a variable), a certain mass of raw materials is weighed and distilled water is added, and homogenized at 60°C (1820×g / 5min). After sufficient dissolution, propylene glycol (glycerol) (25%wt of the total weight of composite PPPs) and polysorbate 80 (40%wt of the total weight of composite PPPs) are added as plasticizers and surfactants; homogenization is continued (1820×g / 5min) to obtain a 3% (w / v) composite PPPs film-forming solution, and the film solution is sterilized at 121°C for 15min, and cooled at room temperature for use.

[0016] Furthermore, the probiotic cell suspension is prepared by the following steps:

[0017] Add 1 mL of 0.85% sodium chloride (w / v) sterile solution to the freeze-dried Lactobacillus plantarum. Then vortex thoroughly and streak on MRS agar medium. After culturing at 37°C for 48 hours, collect a small number of colonies with a sterile loop, suspend in 100 mL of MRS broth, and incubate at 37°C for 48 hours. Then collect the cell microspheres, centrifuge at 6000g, 4°C for 10 minutes. Discard the supernatant and wash the cells with 0.85% sodium chloride (w / v) sterile solution to prepare a probiotic suspension (concentration of 1×10 7 ~1×10 9 CFU / mL).

[0018] Principle description: ① Probiotics usually produce bacteriocins, peptides, organic acids (acetic acid and lactic acid), hydrogen peroxide and diacetyl (protein-derived compounds), which help control pathogenic microorganisms and spoilage microorganisms, thereby achieving fruit and vegetable preservation. Since probiotics are living microorganisms, there are some physical and chemical factors that threaten their survival, such as high temperature, low temperature, pH and Maillard reaction. The use of edible coatings is considered to be a solution to overcome the difficulties in the application of probiotics in fruit and vegetable preservation.

[0019] ② Polysaccharides (such as tofu taro pectin polysaccharide and sodium alginate) are widely used in edible coating formulations due to their abundant sources, biodegradability and easy film-forming properties. In addition to having good mechanical properties, oxygen and oil barrier effects, they also have little effect on the odor of coated fruits and vegetables. However, the hydrophilic nature of polysaccharides leads to their high moisture permeability, so other additives are needed to improve their performance. Glycerol is the most commonly used plasticizer for fruit and vegetable coatings. It can form hydrogen bonds with polysaccharides. This bonding makes the polymer matrix more structurally stable and improves the transparency of the film, thereby improving the water retention and air permeability of the coating. Emulsifiers such as tofu taro pectin polysaccharide and polysorbate 80 are also commonly used in edible coatings containing probiotics to enhance their adhesion to the surface of fruits and vegetables.

[0020] Based on the above technical solution, the embodiments of the present invention can at least produce the following technical effects:

[0021] (1) The composite polysaccharide edible film provided by the present invention can not only serve as a carrier of probiotics, but also improve safety and protect the sensory and nutritional quality of coated fruits and vegetables. The edible coating forms a barrier to water vapor, oxygen and carbon dioxide, reduces the respiration of fruits and vegetables, and provides a high humidity environment, thereby extending the shelf life of fruits and vegetables. In addition, the edible coating can also reduce physical damage to fruits and vegetables caused by impact, pressure or vibration.

[0022] (2) The composite polysaccharide edible film provided by the present invention contains Lactobacillus plantarum, which can improve the physical and chemical properties of fruits and vegetables (such as strawberries), reduce the weight and ascorbic acid loss during cold storage, and will not have a negative impact on the sensory properties of the coated fruits. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 The scanning electron micrographs of the composite polysaccharide edible films prepared with different mass ratios of PPPs / SAA in Example 1 of the present invention; the left image is a horizontal section at 800x, and the right image is a cross section at 2000x, (1) PPPs:SAA (0:100); (2) PPPs:SAA (15:85); (3) PPPs:SAA (30:70); (4) PPPs:SAA (45:55); (5) PPPs:SAA (60:40);

[0024] Figure 2 The contact angle diagrams of the edible composite polysaccharide films prepared with different mass ratios of PPPs / SAA in Example 1 of the present invention; wherein: (1) PPPs:SAA (0:100); (2) PPPs:SAA (15:85); (3) PPPs:SAA (30:70); (4) PPPs:SAA (45:55); (5) PPPs:SAA (60:40);

[0025] Figure 3 The number of viable bacteria in the composite polysaccharide edible film prepared by different mass ratios of PPPs / SAA containing probiotics in Example 2 of the present invention;

[0026] Figure 4 The counts of molds and yeasts in the composite polysaccharide edible film prepared by PPPs / SAA with different mass ratios containing probiotics in Example 2 of the present invention. DETAILED DESCRIPTION

[0027] The following will combine the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention.

[0028] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application; the terms "first", "second", and "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance; in addition, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0029] Example 1

[0030] ① Emulsified microencapsulation process (pretreatment): 5-10 mL of composite tofu pectin polysaccharide film-forming solution (solution A) and 10 mL of a 1×10 7 ~1×10 9CFU / mL concentrated probiotic cell suspension (Solution B) was mixed, and then 8% (m / v) denatured whey protein isolate was added to obtain an edible membrane liquid containing probiotics with a final concentration of 2% complex polysaccharide. Microcrystalline calcium carbonate was added to the above membrane liquid at a concentration of about 1.4mmol. After homogenization, the mixed membrane liquid was dispersed into vegetable oil (sunflower oil, etc.) containing 1% Span 80 (membrane liquid: vegetable oil = 6:4, v / v) using an electric stirrer (600rpm). After 15min of emulsification, 8.7mmol of glacial acetic acid was added using a 1mL syringe and syringe driver (flow rate of 0.05mL min –1 ). Stir continuously for 15 min to dissolve the calcium carbonate. Use 0.05 M calcium chloride (CaCl 2 ) for microcapsule embedding treatment. When the microcapsules are stabilized, the top lipid phase is removed by suction with a vacuum pump, and the residual oil is removed by washing with a 0.05M calcium chloride solution and a 0.9% sodium chloride solution containing 1% Tween 80, thereby obtaining an emulsified microencapsulated edible membrane liquid.

[0031] ② Film preparation process: a certain amount of emulsified microencapsulated edible film liquid is subjected to ultrasonic treatment for 8 to 10 minutes for degassing and defoaming, and then a density of 0.3 g / cm 2 ~0.34g / cm 2 The degassed edible film liquid is evenly spread on the surface of a dried polypropylene plate and dried at 30-35°C for 5-7 hours to obtain a tofu-wood pectin polysaccharide-sodium alginate composite edible film containing probiotics.

[0032] The scanning electron microscopy images of the composite polysaccharide edible films prepared by different mass ratios of PPPs / SAA are shown in Figure 2. Figure 1 The outer layer of each film showed a continuous, non-porous but slightly rough / inhomogeneous surface with small particles / agglomerates, with a dense and compact morphology. The presence of agglomerates is attributed to the Ca 2+ Crosslinking with SAA generates insoluble calcium alginate. In addition, the thickness of the edible film increases with the increase of PPPs concentration, which may be due to the hydrogen bonds formed between glycerol and PPPs, which makes the polymer matrix more stable in structure and increases the thickness of the edible film.

[0033] The contact angle diagrams of the composite polysaccharide edible films prepared by different mass ratios of PPPs / SAA are shown in Figure 2. Figure 2As shown. The water contact angle is generally used to evaluate the wettability of the surface of a polymer film, and can reflect the hydrophobicity or hydrophilicity of the film surface. When the contact angle is lower than 90.00°, the film surface is considered to be hydrophilic, and when the contact angle is higher than 90.00°, the film surface is considered to be hydrophobic. The contact angles of all sample films are greater than 100°, indicating that the tofu pectin-sodium alginate film presents a hydrophobic surface. However, excessive hydrophobicity may affect the growth of microorganisms, and the contact angle of the edible film decreases with the increase of PPPs concentration. It is speculated that PPPs has a strong hydrophilicity and can appropriately reduce the hydrophobicity of the edible film, which is beneficial to the growth of probiotics.

[0034] Example 2 is applied to fresh-cut kiwi fruit preservation

[0035] Kiwifruit samples were purchased from the market, washed with tap water, and then air-dried at room temperature. The kiwifruit samples were manually peeled, sliced ​​with a sterile stainless steel knife, and then coated with a complex polysaccharide edible film solution prepared by PPPs / SAA with different mass ratios containing probiotics (initial probiotic concentration was 9.1±0.10 CFU / mL). Then, the samples (15 freshly cut kiwifruit samples in each treatment) were placed in a fresh-keeping bag (0.4L) with low oxygen and low moisture permeability. Afterwards, the samples were stored at 4°C for 5 days. Microbiological analysis was performed during storage.

[0036] The number of viable bacteria in the composite polysaccharide edible film prepared by different mass ratios of PPPs / SAA containing probiotics (applied to fresh-cut kiwifruit) Figure 3 As shown. Generally speaking, the food industry recommends a probiotic level of 6 log CFU / g as the minimum level of live probiotics that should be present in food when consumed, and the Lactobacillus plantarum in each treatment in the experiment remained at a high level after 5 days of storage, which is sufficient for human use. When PPPs:SAA=30:70, the number of live Lactobacillus plantarum after 5 days of storage was higher than that of other treatments, at 7.6±0.06log CFU / g.

[0037] Counts of molds and yeasts in edible films of composite polysaccharide prepared by different mass ratios of PPPs / SAA containing probiotics (applied to fresh-cut kiwifruit) Figure 4 As shown. The initial counts of the two fungi were 12±1.0 CFU / g, and all treatments increased significantly during storage. The number of molds and yeasts in the uncoated samples reached 49±2.0 CFU / g after 5 days. The use of edible films containing probiotics reduced the number of fungi compared to uncoated fruits. The data showed that when PPPs:SAA=30:70, the edible coating was most effective in reducing the number of molds and yeasts, which was 23±0.9 CFU / g after 5 days of storage, which may be due to the highest number of live Lactobacillus plantarum.

[0038] The structures, functions and connection forms disclosed in this article can be implemented in other ways. For example, the embodiments described above are only exemplary, for example, multiple components can be combined or integrated into another component; in addition, each functional component in each embodiment of this article can be integrated into one functional component, or each functional component can exist physically separately, or two or more functional components can be integrated into one functional component.

[0039] The above is only a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several modifications and improvements without departing from the inventive concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A composite polysaccharide edible film containing probiotics, characterized in that: The composite polysaccharide edible film comprises a composite tofu-tree pectin polysaccharide film-forming solution, a probiotic cell suspension and a denatured whey protein isolate.

2. The edible composite polysaccharide film containing probiotics according to claim 1, characterized in that: The composite tofu chai pectin polysaccharide film-forming solution is prepared by the following steps: The mass ratio of tofu pectin polysaccharide to sodium alginate is 3:

7. Distilled water is added and homogenized. After fully dissolved, glycerol and polysorbate 80 are added and homogenization is continued to obtain a composite tofu pectin polysaccharide film-forming solution with a mass concentration of 3%. The glycerol is 25%wt of the total weight of the composite tofu pectin polysaccharide, and the polysorbate 80 is 40%wt of the total weight of the composite tofu pectin polysaccharide.

3. The edible composite polysaccharide film containing probiotics according to claim 2, characterized in that: The tofu chai pectin polysaccharide is prepared by the following steps: A1. Preparation of tofu taro pectin: 10.0 g tofu taro leaf powder was weighed and added to a pH 5 buffer solution at a w / v 1:10 solid-liquid ratio, stirred evenly, and then treated with dielectric barrier discharge plasma; 2400 U / g of cellulase was added to the treated mixture, and the final solid-liquid ratio was adjusted to 1:40, and the enzymatic hydrolysis time was 1 hour, and the mixture was placed in a shaking incubator for enzymatic hydrolysis; the enzymatic hydrolysis system was treated at 90° C. for 15 minutes to inactivate the enzyme, cooled and centrifuged at 5000 r / min for 10 minutes; the enzymatic hydrolyzate was precipitated with twice the volume of anhydrous ethanol, and allowed to stand for alcohol precipitation for 12 hours, the precipitate was redissolved in water, and the ethanol was removed by vacuum distillation, and freeze-dried to obtain crude pectin; A2. Dissolve the crude pectin of radix fasciatus in distilled water, and use the volume ratio of polysaccharide solution: chloroform: isoamyl alcohol = 25:4:1 to remove impurities such as protein in the crude pectin of radix fasciatus, and then use anhydrous ethanol to precipitate the pectin of radix fasciatus and freeze-dry it; prepare the pectin after protein removal into a 10 mg / mL solution, filter it through a 0.45 μm filter membrane, and purify it with a cellulose DEAE-52 column, and balance it with phosphate buffer containing 0, 0.1, 0.3, and 0.5 M sodium chloride; collect the eluate, and further purify it with a Sephadex G-150 column to obtain pure radix fasciatus pectin polysaccharide.

4. The edible composite polysaccharide film containing probiotics according to claim 3, characterized in that: The detailed parameters of the dielectric barrier discharge plasma treatment are: plate spacing of 30 mm, high-voltage discharge voltage of 130 kV, high-voltage discharge frequency of 50 Hz, discharge duration of 60 s, and discharge gap time of 10 s; the phosphate buffer solution is 0.02 mol / L, and pH = 6.

8.

5. The edible composite polysaccharide film containing probiotics according to claim 1, characterized in that: The probiotic cell suspension is prepared by the following steps: B1. Add a 0.85% sodium chloride sterile solution to the freeze-dried Lactobacillus plantarum, then vortex thoroughly and streak culture on MRS agar medium; B2. After culturing at 37°C for 48 hours, collect a small amount of colonies with a sterile loop, suspend them in 100 mL of MRS broth, and incubate them at 37°C for 48 hours. Then collect the cell microspheres, centrifuge at 6000g, 4°C for 10 min, discard the supernatant, and wash the cells with a sterile sodium chloride solution with a mass concentration of 0.85% to obtain a probiotic cell suspension.

6. A method for preparing a composite polysaccharide edible film containing probiotics, characterized in that: The following steps are involved: S1. Pretreatment of emulsified microcapsules: the composite tofu-tree pectin polysaccharide film-forming solution and the probiotic cell suspension are mixed, and 8% m / v denatured whey protein isolate is added to obtain a 2% composite polysaccharide edible film solution, microcrystalline calcium carbonate is added for homogenization, and the mixture is dispersed in a 40% v / v vegetable oil solution containing an electronic overhead stirrer; after 15 min of emulsification, 8.7 mmol of glacial acetic acid is added, and stirring is continued for 15 min to dissolve the calcium carbonate; 0.05 M calcium chloride is used for microcapsule embedding treatment, and when the microcapsules are stabilized, the top lipid phase is removed by suction with a vacuum pump, and the residual oil is removed by washing with a 0.05 M calcium chloride solution containing 1% Tween 80 and a 0.9% sodium chloride solution in sequence to obtain an emulsified microencapsulated edible film solution; S2. Film preparation: The emulsified microencapsulated edible film liquid was ultrasonically treated for 8 to 10 minutes for degassing and defoaming, and then the density of 0.3 g / cm 2 ~0.34g / cm 2 The degassed edible film liquid is evenly spread on the surface of the polypropylene plate and dried at 30-35° C. for 5-7 hours to obtain a composite polysaccharide edible film containing probiotics.

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