CN102613277A - Nano coating preservation packaging material special for traditional red egg, preparation method and coating method - Google Patents

Abstract

The invention discloses a traditional red egg composite nano-coating fresh-keeping packaging material and a preparation and coating method thereof, belonging to the field of fresh-keeping packaging of egg products. The packaging material is compounded by reacting the following components in aqueous solution: polyvinyl alcohol 40-70g/L, glutaraldehyde 3-5g/L, acid red 1.0-1.5g/L, nano TiO ₂ 0.1-0.4 g/L, nano-SiO ₂ 0.20-0.60g/L. The preparation method comprises: adding nanometer TiO ₂ and SiO ₂ into PVA aqueous solution and ultrasonically mixing, adding glutaraldehyde for constant temperature crosslinking reaction; adding acid red and stirring at constant temperature to prepare the composite nano coating film material. The composite nano-coating fresh-keeping packaging material is hot-coated on the surface of boiled eggs, and the traditional red eggs are obtained after film formation. The invention can simplify the traditional production process of red eggs, significantly reduce the amount of packaging materials, realize mechanized operation, and improve the safety quality of red egg products.

Description

Special nano-coating fresh-keeping packaging material for traditional red eggs and its preparation and coating method

technical field

The invention belongs to the field of fresh-keeping packaging for food, and relates to a film-coated fresh-keeping packaging material for egg products and a preparation method and application thereof, in particular to a special nano-coated fresh-keeping packaging material for traditional red eggs, and a preparation and coating method thereof.

Background technique

China is rich in poultry egg resources and diverse in variety, and is the largest producer and consumer of poultry eggs in the world. Red eggs with traditional festive symbolic meaning have a long history and are often used in various festive occasions such as marriage and childbirth. Traditional red eggs are prepared by manually applying red dye to the surface of the eggshell. The production efficiency is low, and the red dye used has certain safety hazards, which affects the edible and commodity value of the product. At present, commercially available Red Happiness Eggs are generally vacuum-packed with red plastic film. This method generally requires three high-temperature treatments, the production process is complicated, the efficiency is low, and the labor cost and packaging cost are high. , energy-saving and low-carbon" national industrial development direction, and the 3-time high-temperature treatment production process seriously affects the nutritional flavor quality of the product.

The development direction of the traditional food industry is the development direction of the traditional food industry by adopting new materials, new processes and new technologies, developing new products, and realizing mechanized operations to improve production efficiency, reduce production costs, ensure food safety, and reduce packaging waste; coating fresh-keeping technology for poultry and egg products Commercial application has started. Therefore, the development of an environmentally friendly coating film fresh-keeping packaging material dedicated to traditional red eggs can simplify the traditional production process, reduce the amount of packaging materials, prolong the shelf life and improve economic benefits, which is in line with the national industrial development of energy saving, emission reduction, low carbon and green strategy.

Contents of the invention

The purpose of the present invention is to provide an environment-friendly composite nano-coated fresh-keeping packaging material specially used for traditional red eggs and its preparation and coating method, so as to solve the complicated and inefficient production process of traditional red eggs using red plastic film vacuum packaging. , high packaging costs and other issues, so that traditional red eggs can achieve high efficiency, energy saving and emission reduction, green and low-carbon large-scale automated production methods on the basis of maintaining traditional characteristics.

The technical solution adopted to solve the technical problems of the present invention is:

A traditional red egg composite nano-coating fresh-keeping packaging material, which is formed by reacting and compounding the following components in an aqueous solution, including:

(1) Polyvinyl alcohol, 40g/L-70g/L;

(2) Glutaraldehyde, 3g/L-5g/L;

(3) Acid red, 1.0g/L-1.5g/L;

(4) Nano-TiO ₂ , 0. 1g/L-0. 4g/L; Nano-SiO ₂ , 0. 20g/L-0. 60g/L.

The acid red is azorubin, whose molecular formula is C ₂₀ H ₁₂ N ₂ Na ₂ O ₇ S ₂ , meets the requirements of GB2760, and belongs to food additives and food colorants.

The preparation method of described composite nano-coating fresh-keeping packaging material comprises the following steps:

Step 1), adding nano-TiO ₂ and nano-SiO ₂ to polyvinyl alcohol aqueous solution for ultrasonic mixing to form a uniform mixed solution;

Step 2), stir and heat the mixed solution in step 1), add glutaraldehyde, and maintain the temperature for cross-linking reaction;

Step 3), adding acid red to the reaction product of step 2), stirring evenly at a constant temperature, and then preparing the composite nano-coated fresh-keeping packaging material.

In the above preparation method, the ratio of each component is: polyvinyl alcohol 40g/L-70g/L, glutaraldehyde 3g/L-5g/L, acid red (azorubin) 1.0g/L-1.5g /L, nano-TiO ₂ 0. 1g/L-0. 4g/L, and nano-SiO ₂ 0. 20g/L-0. 60g/L.

In step 1), the ultrasonic mixing time is preferably 15-20 minutes, and the ultrasonic power density is preferably 70-80W/L.

In step 2), the preferred reaction conditions are heating temperature of 85-95°C and reaction time of 40-50 minutes.

In step 3), the stirring time is preferably 10-20 minutes.

The present invention also relates to the film coating method of the traditional red egg nano-preservation packaging material, that is, the traditional red egg film-coated fresh-keeping packaging manufacturing process: after heating and stirring the nano-coated fresh-keeping packaging material, it is hot-coated on the surface of cooked eggs, and hot air Blow dry evenly to form a film, and then repeat hot coating more than once.

The specific method of film formation in the production of traditional red eggs is: heating 15g/L -25 g/L saline solution, when the temperature difference between the salt water and the eggs is 50-60°C, put the eggs into the salt water and cook; The film fresh-keeping packaging material is heated and stirred until the temperature reaches 85-95°C, and hot-coated on the surface of eggs boiled in salt water (keep the surface temperature of the egg above 70°C), and the hot air is evenly dried to form a film, and then repeat the hot-coating more than once.

The advantages of the present invention are:

(1) According to the present invention, an environment-friendly nano-coating material is used in the traditional red egg production process to coat fresh-keeping packaging, the production process is simple, and mechanization can be realized to greatly improve production efficiency and reduce labor costs. Compared with the production methods of egg plastic film vacuum packaging, it can significantly reduce the amount of packaging materials, and the packaging waste is environmentally friendly and can be completely decomposed, avoiding the white pollution of plastic packaging, so that traditional red eggs can achieve high efficiency, energy saving and emission reduction on the basis of maintaining traditional characteristics. The low-carbon and green modern production method significantly improves its scale production capacity and economic benefits.

(2) The acid red (azorubin) used in the preparation of traditional nano-coating materials for red eggs is an additive directly applied to food. It is hygienic and safe, and the color is bright red. Compared with eggs, it improves food safety and product commerciality.

(3) Using nano-TiO ₂ and SiO ₂ to modify the polyvinyl alcohol-based composite coating material can significantly improve the antibacterial and fresh-keeping function of the polyvinyl alcohol-based composite coating material; significantly reduce the film-forming moisture permeability of the material, and effectively improve its Film-forming water resistance and barrier properties.

Description of drawings

Fig. 1A, Response surface curves of the effects of nano-SiO ₂ and nano-TiO ₂ on the water vapor transmission rate of the composite film.

Fig. 1B, Contours of the effects of nano-SiO ₂ and nano-TiO ₂ on the water vapor transmission rate of the composite film.

Fig. 2A, the response surface curve of the effect of nano-SiO ₂ and glutaraldehyde on the water vapor transmission rate of the composite film.

Fig. 2B. Response surface curves of the effects of nano-SiO ₂ and glutaraldehyde on the water vapor transmission rate of the composite film.

Figure 3. The effect of glutaraldehyde addition on the antibacterial performance of the composite film.

Detailed ways

The present invention will be further described below in conjunction with embodiment. In the following examples, unless otherwise specified, the concentration g/L (w/v _water ) of the components refers to the concentration of the components in the composite coating fresh-keeping packaging material in the aqueous solution after mixing.

Example 1

According to the traditional nano-coated fresh-keeping packaging material for red eggs according to the present invention, its preparation method is: adding a certain amount of nano-TiO ₂ and nano-SiO ₂ into a 50g/L PVA aqueous solution according to the proportion, and placing it in an ultrasonic water bath , Ultrasound for 15-20 minutes under the condition of power density 70-80W/L, so that nano-TiO ₂ and SiO ₂ are uniformly dispersed in polyvinyl alcohol aqueous solution, the mixed solution is heated and stirred until the temperature reaches 85-95 °C, and a certain amount of pentamethylene Dialdehyde was added to the above-mentioned nanomaterial-polyvinyl alcohol mixture, kept warm and stirred for 40-50 minutes; 1.2g/L acid red (azorubin) was added to the above-mentioned glutaraldehyde-nanomaterial-polyvinyl alcohol solution, and kept at constant temperature Stir for 10-20 minutes to prepare the composite nano-coating film material.

Among them, the addition amounts of nano-TiO ₂ , nano-SiO ₂ and glutaraldehyde were added according to the response surface experiment design table in Table 1.

Table 1 Response surface experiment design of the addition amount of various factors of red composite nano-coating fresh-keeping packaging materials

                                                 

In order to test the film-forming performance characteristics of the traditional nano-coated fresh-keeping packaging materials specially used for red eggs, the film liquid of the nano-coated packaging materials was put into a flat-bottomed vessel, dried in vacuum at 55-60°C for 5-7 hours, and then the film was peeled off to form a film. The thickness is 0.07mm, and then the film-forming performance characteristics such as moisture permeability (23°C, 80%RH), moisture absorption rate (23°C, 80%RH) and antibacterial property are measured, and the results are shown in Table 2.

Table 2 Response surface test results of film-forming performance characteristics of red composite nano-coating fresh-keeping packaging materials

 

The antibacterial properties of the traditional nano-coated fresh-keeping packaging materials for red eggs can be compared by the size of the antibacterial zone. Among them, the PVA composite film containing only nanomaterials did not show obvious antibacterial effect, when glutaraldehyde was added, the antibacterial effect of the composite film was improved, and the effect of glutaraldehyde addition on the antibacterial effect of the composite film Figure 3 shows.

Multivariate regression fitting analysis was performed on the experimental data with the response value of the moisture permeability of the composite membrane. The effects of nano-TiO ₂ , nano-SiO ₂ and glutaraldehyde on the moisture permeability of the composite membrane are shown in Table 2, Figure 1 and Figure 2 , in which nano-TiO ₂ and nano-SiO ₂ , nano-SiO ₂ and glutaraldehyde have a significant interaction on the water vapor transmission rate of the red nano-composite coating material, and the influence of the three on the water vapor transmission rate of the traditional red egg-specific coating material is all There is an inflection point, and the addition within a certain range helps to reduce the moisture permeability of the composite film. The composite nano-coating prepared in the range of glutaraldehyde 3g/L-5g/L, nano- _TiO2 0.1g/L-0.4g/L, nano-SiO2 _0.20g /L-0.60g/L Film fresh-keeping packaging materials have ideal moisture permeability.

Example 2

Add nano-TiO ₂ and nano-SiO ₂ to 40g/L PVA aqueous solution at a ratio of 0.1g/L and 0.2g/L respectively, place in an ultrasonic water bath, and ultrasonicate for 15 minutes under the condition of a power density of 80W/L. Make nano-TiO ₂ and nano-SiO ₂ uniformly dispersed in polyvinyl alcohol aqueous solution; heat and stir the mixed solution until the temperature reaches 88°C, add glutaraldehyde in the ratio of 3g/L to the above-mentioned nano-material-polyvinyl alcohol mixed liquid, keep warm Stir for 45 minutes; add 1.2 g/L acid red (azorubin) into the above-mentioned glutaraldehyde-nanomaterial-polyvinyl alcohol solution, and stir at constant temperature for 15 minutes to prepare a composite nano-coating material. The film-forming performance of the composite coating fresh-keeping packaging material was tested, and the moisture permeability was 6.077 g*m ^-2 *h ^-1 , and the diameter of the inhibition zone was 20.14mm.

Example 3

Add nano-TiO ₂ and nano-SiO ₂ to 70g/L PVA aqueous solution according to the ratio of 0.4g/L and 0.6g/L respectively, place in an ultrasonic water bath, and ultrasonicate for 15 minutes under the condition of power density 80W/L. Make nano TiO ₂ and nano SiO ₂ uniformly dispersed in the polyvinyl alcohol aqueous solution; heat and stir the mixed solution until the temperature reaches 88°C, add glutaraldehyde in the ratio of 5g/L to the above nanomaterial-polyvinyl alcohol mixed solution, keep warm Stir for 45 minutes; add 1.2 g/L acid red (azorubin) into the above-mentioned glutaraldehyde-nanomaterial-polyvinyl alcohol solution, and stir at constant temperature for 15 minutes to prepare a composite nano-coating material. The film-forming efficiency of the composite coating fresh-keeping packaging material was tested, and the moisture permeability was 4.775 g*m ^-2 *h ^-1 , and the diameter of the inhibition zone was 21.43mm.

Example 4

Utilize the film-coated fresh-keeping packaging material prepared in Example 3 to make traditional red eggs. The specific method is: heat 15g/L-25 g/L saline solution, and when the temperature of the saline is 50-60°C higher than room temperature, Boil the eggs placed at room temperature in salt water; heat and stir the composite nano-coating fresh-keeping packaging material until the temperature reaches 85-95°C; After about 20 seconds in the film solution, take out the hot air and blow it dry evenly to form a film, and then repeat the heat coating once.

Each egg consumes about 3g of coating solution, and the weight of the egg increases by about 0.1g after drying to form a film. Compared with the plastic film vacuum packaging material consumption of 1.8g, it can reduce the packaging material consumption by more than 90%, and significantly reduce the packaging cost. Moreover, in the present invention, eggs are boiled and dipped directly in the film liquid at 85-95°C, and then dried by hot air to form a film on the surface of the eggshell, which can realize the automatic production mode of machinery, and while greatly improving the production efficiency, it also avoids the current Commercially available Red Happiness Eggs are vacuum-packed with red plastic film and require three high-temperature treatments, which seriously affects the nutrition and flavor quality of the product. In addition, the red eggs made of special nano-coating material film packaging maintain the product image of traditional red eggs, and the shelf life of the product can meet the needs of the circulation and sales cycle, improving the safety, quality and commerciality of the product.

It can be seen that the special nano-coated fresh-keeping packaging material for traditional red eggs and its preparation and coating method of the present invention provide a new material and new technology for the large-scale production of traditional red eggs, which will completely change the traditional production method and make traditional red eggs On the basis of maintaining traditional characteristics, it can realize modern mechanical automation production methods with high efficiency, energy saving and emission reduction, low carbon and green, and significantly improve its scale production capacity and economic benefits.

Claims (8)

1. conventional red egg composite Nano coating-film fresh-keeping packaging material is characterized in that, are reacted in the aqueous solution by following component to be composited, and comprising:

(1) polyvinyl alcohol, 40g/L-70g/L;

(2) glutaraldehyde, 3g/L-5g/L;

(3) acid red, 1.0g/L-1.5g/L;

(4) nano-TiO ₂, 0. 1g/L-0. 4g/L; With nanometer SiO ₂, 0. 20g/L-0. 60g/L.

2. composite Nano coating-film fresh-keeping packaging material according to claim 1 is characterized in that: described acid red molecular formula is C ₂₀H ₁₂N ₂Na ₂O ₇S ₂, meet the GB2760 requirement.

3. the preparation method of the described conventional red egg of claim 1 composite Nano coating-film fresh-keeping packaging material may further comprise the steps:

1), with nano-TiO ₂, nanometer SiO ₂Add ultrasonic mixing in the polyvinyl alcohol water solution to, form even mixed solution;

2), the mixed solution agitating heating of step 1) is heated up, add glutaraldehyde, holding temperature is carried out cross-linking reaction;

3) in the product, acid red is added above-mentioned steps 2), constant temperature stirs, and promptly makes described composite Nano coating-film fresh-keeping packaging material.

4. the preparation method of composite Nano coating-film fresh-keeping packaging material according to claim 3 is characterized in that: ultrasonic incorporation time is 15-20 minute in the step 1), and ultrasonic power density is 70-80W/L.

5. the preparation method of composite Nano coating-film fresh-keeping packaging material according to claim 3 is characterized in that: step 2) in heating-up temperature be 85-95 ℃, the reaction time is 40-50 minute.

6. the preparation method of composite Nano coating-film fresh-keeping packaging material according to claim 3 is characterized in that: the constant temperature mixing time is 10-20 minute in the step 3).

7. the packing manufacture craft of filming of a conventional red egg is characterized in that: after composite Nano coating-film fresh-keeping packaging material heated and stirred, heat is applied to ripe egg surface, and hot blast evenly dries up film forming; More than repetition heat is coated with once;

Described composite Nano coating-film fresh-keeping packaging material are reacted in the aqueous solution by following component and are composited, and comprising:

(1) polyvinyl alcohol, 40g/L-70g/L;

(2) glutaraldehyde, 3g/L-5g/L;

(3) acid red, 1.0g/L-1.5g/L;

(4) nano-TiO ₂, 0. 1g/L-0. 4g/L; Nanometer SiO ₂, 0. 20g/L-0. 60g/L.

8. the packing manufacture craft of filming of conventional red egg according to claim 7; It is characterized in that; The concrete grammar of said manufacture craft is that heating 15g/L-25 g/L saline solution is put into salt solution with egg and boiled when the temperature difference of salt solution and egg is 50-60 ℃; With composite Nano coating-film fresh-keeping packaging material heated and stirred, reach 85-95 ℃ to temperature, heat is applied to the ripe egg surface of surface temperature more than 70 ℃, and hot blast evenly dries up film forming, repeats more than heat is coated with once again.

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