CN111647205A - Edible film and preparation method and application thereof - Google Patents

Abstract

The invention provides an edible film and a preparation method and application thereof, wherein the edible film comprises the following components in percentage by mass: 60-80% of purified water, 5-15% of compound food gum, 10-25% of pullulan, 5-10% of maltodextrin, 0.05-0.1% of compound preservative, 2-5% of plasticizer, 1-2% of thickening agent, 0.05-0.1% of food defoaming agent and 0.1-0.5% of guarana extract. The invention greatly improves the weather resistance of the film material by the synergistic action of a plurality of film forming agents, plasticizers and thickeners and screening and optimizing the plasticizers and thickeners in a large amount, greatly reduces the influence of product performances at ambient temperature and humidity, ensures that the film material conforms to the national food safety standard, has excellent mechanical property, oxidation resistance, water and oil resistance, hot water instant solubility and weather resistance, improves the applicability of the product, and can be used for preparing films, food packaging bags and carriers of printing or printing processes.

Description

Edible film and preparation method and application thereof

Technical Field

The invention belongs to the technical field of food materials, and particularly relates to an edible film and a preparation method thereof.

Background

The edible film is prepared by mixing, heating, coating, drying and the like by using edible materials, and is a film which can be edible, can keep food fresh and has a packaging protection function. The film with a porous network structure is formed by taking natural edible substances (such as polysaccharide, protein, fat and the like) as raw materials through the interaction between different molecules, can be coated on the surface of food in the forms of coating, microcapsules and the like, can prevent the permeation of water vapor, other gases or various solutes, plays a role in protection, ensures the quality of the food and prolongs the shelf life of the food.

However, the current edible films have the problems of insufficient mechanical strength, poor heat sealability, poor water and oil resistance, poor bacteriostatic effect, poor weather resistance and the like in application. Moreover, most of edible film products published in the domestic patents and papers are in the laboratory stage, and the following problems exist in the industrialized mass production: the product has excellent performance under laboratory conditions, and the performance is seriously reduced after mass production; secondly, the existing edible film raw materials are mainly food-grade food additives, the product can be ensured to have strength and toughness only by containing proper moisture, when the production environment and the use environment (temperature and humidity) are greatly changed, the product performance can be reversed due to the moisture content change of the film, the product stability is insufficient, and the use condition is harsh; the film product has poor storage stability and short shelf life, and the industrialization of the product is seriously limited.

Disclosure of Invention

The invention aims to solve the problems of insufficient mechanical strength, poor heat sealability, poor water resistance and oil resistance, poor antibacterial effect, poor weather resistance and the like of the existing edible film.

To this end, the invention provides an edible film comprising the following components in mass percent: 60-80% of purified water, 5-15% of compound food gum, 10-25% of pullulan, 5-10% of maltodextrin, 0.05-0.1% of compound preservative, 2-5% of plasticizer, 1-2% of thickening agent, 0.05-0.1% of food defoaming agent and 0.1-0.5% of guarana extract.

Further, the compound food gum is a composition of gelatin and welan gum, and the mass ratio of the gelatin to the welan gum is 1: 1-3: 1.

Further, the mass ratio of the gelatin to the welan gum is 2: 1.

Further, the gelatin has a freezing force value of more than 240 g.

Further, the compound preservative is a composition of polylysine and lysozyme in a mass ratio of 1:1, or a composition of potassium sorbate and citric acid in a mass ratio of 1: 1.

Further, the plasticizer is a composition of glycerol and any one of triacetin, triethyl citrate, erythritol and isomaltitol, and the mass ratio of the glycerol to any one of triacetin, triethyl citrate, erythritol and isomaltitol is 0.1-0.3: 1.

Further, the thickening agent is any one of propylene glycol alginate, sodium alginate and carboxymethyl cellulose.

Further, the food antifoaming agent is any one of polydimethylsiloxane, polyoxyethylene polyoxypropylene ether and polyoxyethylene (20) sorbitan monolaurate.

In addition, the invention also provides a preparation method of the edible film, which comprises the following steps:

1) heating a mixing tank to 50-70 ℃ and keeping the temperature constant, opening a stirring paddle, stirring at the speed of 300-500 r/min, weighing raw materials according to the formula proportion, sequentially adding purified water, compound food gum, pullulan, maltodextrin, compound preservative and plasticizer into the mixing tank, stirring at the constant temperature for 1-2 hours, and fully dissolving;

2) sequentially adding weighed thickener, food defoamer and guarana extract into the raw materials dissolved in the step 1), increasing the stirring speed to 1000-1200 r/min, and continuously stirring for 1-2 hours at constant temperature to obtain membrane liquid;

3) keeping the constant temperature of the membrane liquid at 50-60 ℃, and detecting the viscosity of the membrane liquid;

4) after the viscosity of the membrane liquid meets the specified requirements, introducing the membrane liquid into a vacuum defoaming tank, and defoaming for 0.5-1 hour at constant temperature;

5) and carrying out a tape casting production process on the defoamed membrane liquid, and slowly baking the membrane liquid in a tape casting machine to gradually lose moisture to form a compact membrane material.

The invention also provides application of the edible film, and the edible film is used for preparing films, food packaging bags and carriers of printing or printing processes.

The invention has the beneficial effects that:

(1) the edible film provided by the invention meets the national food safety standard through the synergistic effect of a plurality of film forming agents, plasticizers and thickeners, and has excellent mechanical property, oxidation resistance, water and oil resistance, hot water instant solubility and weather resistance.

(2) The edible film provided by the invention is optimized by screening a large amount of the plasticizer and the thickening agent, and the optimized proportion of the compounded plasticizer and the thickening agent can greatly improve the weather resistance of the film material, greatly reduce the influence of the environmental temperature and the humidity on the performance of the product and improve the applicability of the product.

Detailed Description

The technical solutions in the embodiments of the present invention are clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention provides an edible film, which comprises the following components in percentage by mass: 60-80% of purified water, 5-15% of compound food gum, 10-25% of pullulan, 5-10% of maltodextrin, 0.05-0.1% of compound preservative, 2-5% of plasticizer, 1-2% of thickening agent, 0.05-0.1% of food defoaming agent and 0.1-0.5% of guarana extract.

Specifically, in the formula of the embodiment, the compound food gum is a composition of gelatin and welan gum, the mass ratio of the gelatin to the welan gum is 1: 1-3: 1, preferably the mass ratio of the gelatin to the welan gum is 2:1, and the two kinds of gums are compounded and cooperated to ensure that the film has more excellent stability and water holding property; wherein the gelatin freezing force value is required to be more than 240. The compound preservative adopts a composition of polylysine and lysozyme in a mass ratio of 1:1 or a composition of potassium sorbate and citric acid in a mass ratio of 1:1, and the compound preservative has more excellent preservative effect than a single preservative. The plasticizer is a composition of glycerol and any one of triacetin, triethyl citrate, erythritol and isomaltitol, the mass ratio of the glycerol to the triacetin to any one of the triethyl citrate to the erythritol and the isomaltitol is 0.1-0.3: 1, the moisture content in a final product is reduced through synergistic plasticization, and the plasticizer has excellent mechanical properties and flexibility, so that the performance loss caused by water loss in the product storage and use environment is solved, and the weather resistance of the product is improved. The thickening agent adopts any one of propylene glycol alginate, sodium alginate and carboxymethyl cellulose, so that the film liquid reaches the optimal production viscosity, and the film forming and drying production links are facilitated. The food defoaming agent is one of polydimethylsiloxane, polyoxyethylene polyoxypropylene ether and polyoxyethylene (20) sorbitan monolaurate. The guarana extract mainly comprises guarana factors, theobromine, purine amino acid, mineral substances and other special activity factors, has the effects of refreshing brain, relieving abdominal pain, recovering physical strength, supplementing energy and improving human body functions, and has mild effect on human bodies and no harm.

The preparation method of the edible film comprises the following specific processes:

(1) heating a mixing tank to 50-70 ℃ and keeping the temperature constant, opening a stirring paddle, stirring at the speed of 300-500 r/min, weighing the raw materials according to the formula proportion, sequentially adding purified water, compound food gum, pullulan, maltodextrin, compound preservative and plasticizer into the mixing tank, stirring at the constant temperature for 1-2 hours, and fully dissolving.

(2) And (2) sequentially adding the weighed thickener, food defoamer and guarana extract into the raw materials dissolved in the step (1), increasing the stirring speed to 1000-1200 r/min, and continuously stirring for 1-2 hours at constant temperature to obtain membrane liquid.

(3) Keeping the constant temperature of the membrane liquid at 50-60 ℃, detecting the viscosity of the membrane liquid, and allowing the detected viscosity of the membrane liquid to meet the specified requirements so as to enter a subsequent production link.

(4) And after the viscosity of the membrane liquid meets the specified requirements, introducing the membrane liquid into a vacuum defoaming tank, and defoaming at constant temperature for 0.5-1 hour.

(5) And (3) carrying out a casting production process on the defoamed membrane liquid, adjusting parameters such as air pressure, casting speed, liquid level height and knife height of a casting machine, sequentially reducing the heating temperature of each section, wherein the temperature section is 50-70 ℃, opening a feeding valve to start casting production after the equipment is balanced for 0.5 hour, and slowly baking the membrane liquid in the casting machine to gradually lose moisture to form a compact membrane material.

The edible film of the invention can be used for making films, food packaging bags, carriers for printing or printing processes.

The performance effects of the edible films of the present invention are illustrated by the specific examples below.

Example 1:

the embodiment provides an edible film, which comprises the following components in percentage by mass: 60% of purified water, 5% of compound food gum, 25% of pullulan polysaccharide, 5% of maltodextrin, 0.1% of compound preservative, 2.3% of plasticizer, 2% of thickening agent, 0.1% of food defoaming agent and 0.5% of guarana extract. The compound food gum is a composition of gelatin and welan gum in a mass ratio of 1:1, the compound preservative is a composition of polylysine and lysozyme in a mass ratio of 1:1, the plasticizer is a composition of glycerol and erythritol in a mass ratio of 0.2:1, the thickening agent is sodium alginate, and the food defoaming agent is polydimethylsiloxane.

The edible film of the embodiment is manufactured into a film sheet with a designed size through processes of rolling, cutting and the like after the dense film material is formed by the preparation method.

Example 2:

the embodiment provides an edible film, which comprises the following components in percentage by mass: 69.7% of purified water, 8% of compound food gum, 20% of pullulan polysaccharide, 5% of maltodextrin, 0.1% of compound preservative, 3% of plasticizer, 2% of thickening agent, 0.1% of food defoaming agent and 0.1% of guarana extract. The compound food gum is a composition of gelatin and welan gum in a mass ratio of 2:1, the compound preservative is a composition of potassium sorbate and citric acid in a mass ratio of 1:1, the plasticizer is a composition of glycerol and erythritol in a mass ratio of 0.3:1, the thickening agent is sodium alginate, and the food defoaming agent is polydimethylsiloxane.

Comparative example 1:

this comparative example used a commercially available gelatin-based edible film.

Comparative example 2:

the comparative example adopts an edible film compounded by gelatin and pullulan.

Comparative example 3:

the composition of the edible film in this comparative example was substantially the same as example 2, except that the plasticizer in this comparative example was glycerin.

Comparative example 4:

the composition of the edible film in this comparative example was substantially the same as example 2, except that the plasticizer in this comparative example was propylene glycol.

Comparative example 5:

the composition of the edible film in this comparative example was substantially the same as example 2, except that the plasticizer in this comparative example was polyethylene glycol 200.

Comparative example 6:

the composition of the edible film in this comparative example was substantially the same as example 2, except that the plasticizer in this comparative example was triethyl citrate.

Comparative example 7:

the composition of the edible film in this comparative example was substantially the same as example 2, except that the thickener in this comparative example was xanthan gum.

Comparative example 8:

the composition of the edible film in this comparative example was substantially the same as that of example 2, except that the thickener in this comparative example was sodium carboxymethyl cellulose.

Comparative example 9:

the composition of the edible film in this comparative example was substantially the same as that of example 2, except that the thickener in this comparative example was sodium carboxymethyl starch.

Tensile strength, elongation at break and weather resistance were measured for examples 1 and 2 and comparative examples 1 to 9, and the results are shown in table 1.

Specifically, tensile strength test conditions: the method comprises the following steps of cutting a membrane into membranes with the width of 10mm, the thickness of 0.08mm and the length of 100mm at the ambient temperature of 23 ℃ and the humidity of 60%, carrying out a tensile test on the membranes by adopting a tensile testing machine, measuring the breaking force of the membranes when the membranes are broken, and calculating to obtain the tensile strength in unit MPa, wherein the tensile speed is 50 mm/min.

Elongation at break test conditions: and when the diaphragm is tested by a tensile machine at the ambient temperature of 23 ℃ and the humidity of 60%, recording the length change of the diaphragm before and after stretching, and calculating to obtain the breaking elongation.

Weather resistance test conditions: the weather resistance is tested by two methods, two environmental conditions are preset, the first is 23 ℃ and 40% of air humidity, the second is 23 ℃ and 70% of air humidity, and a sample is placed in a preset environment to be balanced for 24 hours and then tested; the folding resistance and the drying weight loss of the diaphragm are tested under two different environments, the folding resistance is tested by adopting a paperboard folding resistance instrument, and the limit bending times of the diaphragm before fracture are tested.

Table 1: properties of edible films

As can be seen from examples 1 and 2 and comparative examples 1 and 2 in table 1, the existing commercially available edible film products show large performance difference in high and low humidity environments, the moisture content is greatly influenced by the environmental humidity, high humidity water absorption and low humidity water loss result in large difference in folding endurance test results, which indicates that the existing commercially available edible film products have poor weather resistance and need to restrict strict environmental temperature and humidity during production and use. The edible film provided by the invention has higher tensile strength than a comparative example and nearly breaking elongation in the same environment (the temperature is 23 ℃ and the humidity is 60%); the weather resistance (folding resistance and drying weight loss) data tested in different environments show that the moisture content in the film is not obviously changed and the folding resistance is in the same level under the high and low humidity environments of the edible film prepared by the invention, namely, the influence of the environmental humidity on the film is very small, the weather resistance is excellent, the requirements of the product on the production and use environments are low, and the edible film is suitable for industrial production and application.

As can be seen from the example 2 and the comparative examples 3, 4, 5 and 6 in the table 1, under the same system, the performance of the membrane is tested by changing the types of the plasticizers and keeping the proportion of other raw materials unchanged, and the performance of the membrane with each component has a larger difference; comparative examples 3-6 are single system plasticizers, the tensile strength of the film is lower than that of the film prepared by adopting the compound plasticizer in the embodiment 2 of the invention, and the weather resistance is slightly poor; data analysis of each proportion of 3-6 shows that under the current formula system, the plasticizer with the same addition amount has the following characteristics: the edible film adopts the plasticizer of a compound system, and the tensile strength and the weather resistance effect are better.

As can be seen from example 2 and comparative examples 7, 8 and 9 in Table 1, the performance of the membrane is greatly influenced by replacing the type of the thickening agent in the same formula system; the thickening agent selected in the embodiment 2 of the invention is sodium alginate, which can enhance the membrane system while thickening the solution, and can form a stable system with better mechanical properties in cooperation with other coating agents such as pullulan and gelatin, so that the tensile strength is obviously improved, and the folding resistance of the membrane in different humidity environments is greatly improved, thereby greatly improving the mechanical properties of the membrane.

The above examples are merely illustrative of the present invention and should not be construed as limiting the scope of the invention, which is intended to be covered by the claims and any design similar or equivalent to the scope of the invention.

Claims (10)

1. An edible film is characterized by comprising the following components in percentage by mass: 60-80% of purified water, 5-15% of compound food gum, 10-25% of pullulan, 5-10% of maltodextrin, 0.05-0.1% of compound preservative, 2-5% of plasticizer, 1-2% of thickening agent, 0.05-0.1% of food defoaming agent and 0.1-0.5% of guarana extract.

2. The edible film according to claim 1, wherein the compound food gum is a composition of gelatin and welan gum, and the mass ratio of the gelatin to the welan gum is 1: 1-3: 1.

3. An edible film according to claim 2, wherein the gelatin and welan gum are present in a 2:1 mass ratio.

4. An edible film according to claim 2, wherein said gelatin has a freezing force value of greater than 240 g.

5. The edible film according to claim 1, wherein the compound preservative is a composition of polylysine and lysozyme in a mass ratio of 1:1, or a composition of potassium sorbate and citric acid in a mass ratio of 1: 1.

6. The edible film according to claim 1, wherein the plasticizer is a combination of glycerol triacetate, triethyl citrate, erythritol and isomalt, and glycerol, and the mass ratio of the glycerol to any of the glycerol triacetate, triethyl citrate, erythritol and isomalt is 0.1-0.3: 1.

7. An edible film according to claim 1, wherein said thickener is any one of propylene glycol alginate, sodium alginate, carboxymethyl cellulose.

8. The edible film according to claim 1, wherein said food antifoaming agent is any one of polydimethylsiloxane, polyoxyethylene polyoxypropylene ether, polyoxyethylene (20) sorbitan monolaurate.

9. A method of preparing an edible film according to any one of claims 1 to 8, comprising the steps of:

1) heating a mixing tank to 50-70 ℃ and keeping the temperature constant, opening a stirring paddle, stirring at the speed of 300-500 r/min, weighing raw materials according to the formula proportion, sequentially adding purified water, compound food gum, pullulan, maltodextrin, compound preservative and plasticizer into the mixing tank, stirring at the constant temperature for 1-2 hours, and fully dissolving;

2) sequentially adding weighed thickener, food defoamer and guarana extract into the raw materials dissolved in the step 1), increasing the stirring speed to 1000-1200 r/min, and continuously stirring for 1-2 hours at constant temperature to obtain membrane liquid;

3) keeping the constant temperature of the membrane liquid at 50-60 ℃, and detecting the viscosity of the membrane liquid;

4) after the viscosity of the membrane liquid meets the specified requirements, introducing the membrane liquid into a vacuum defoaming tank, and defoaming for 0.5-1 hour at constant temperature;

5) and carrying out a tape casting production process on the defoamed membrane liquid, and slowly baking the membrane liquid in a tape casting machine to gradually lose moisture to form a compact membrane material.

10. Use of an edible film according to any of claims 1 to 8, wherein the edible film is used to form films, food packaging bags, supports for printing or printing processes.