Food packaging material integrating fresh-keeping and freshness monitoring functions and application
By constructing multifunctional nanofillers and using them for ethyl cellulose membrane materials, the shortcomings of existing bio-based intelligent packaging materials in fresh preservation and freshness monitoring functions are solved, and the mechanical properties and functional properties of the materials are improved, and low-cost and excellent performance are obtained.
Patent Information
- Application Number
- CN202411956716.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-29
- Publication Date
- 2025-03-28
AI Technical Summary
The existing bio-based intelligent packaging materials have shortcomings in freshness monitoring functions and freshness monitoring functions, and the extraction of natural pigments is complex and costly, which limits their application.
By reacting 3-phenyl-2-acrylic acid with ferrous sulfate, a multifunctional nanofiller is constructed and used as a functional filler for the ethyl cellulose film material to improve the mechanical properties, barrier properties and functionality of the material.
The mechanical strength, toughness, antibacterial activity, antioxidant activity and freshness monitoring functions of ethyl cellulose membrane materials have been improved, and a food packaging material that integrates freshness and freshness monitoring functions with low cost and excellent performance has been obtained.
Smart Images
Figure CN119708650A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of polymer composite materials, and in particular relates to a food packaging material integrating freshness preservation and freshness monitoring functions and an application thereof. Background Art
[0002] As the storage time of fresh fruits, vegetables and meat increases, their storage qualities such as color, texture and flavor gradually decrease. They are also susceptible to physiological diseases and microbial invasion. Therefore, fresh-keeping treatment of food during storage is a necessary measure to maintain the nutritional quality and commodity attributes of fruits, vegetables and meat. The rise and development of nanotechnology has provided new ideas and methods for food preservation during storage. In particular, fresh-keeping nano packaging materials use nanotechnology to modify packaging materials to improve their barrier properties, antibacterial properties and mechanical properties; this material can effectively prevent the invasion of oxygen, moisture and microorganisms, thereby extending the shelf life of food and bringing more convenience to people. In addition, food packaging materials with freshness monitoring function, as a simple and effective intelligent packaging technology, can directly and scientifically indicate the freshness of food without complicated operations. Among them, pH / ammonia-sensitive color-changing intelligent packaging is one of the most popular intelligent packaging, which monitors corruption information by changes in pH / ammonia atmosphere concentration. When protein-rich food is corrupted, ammonia and organic amines are released, causing the pH value of the surrounding environment to change. Therefore, exploring food packaging materials that integrate preservation and freshness monitoring functions is an effective way to solve the problems of food safety and food waste.
[0003] Recently, bio-based smart packaging materials integrated with natural pigments have attracted people's interest because of their ability to evaluate the freshness of stored foods and delay their deterioration. However, the extraction process of natural pigments (e.g., anthocyanins, curcumin, etc.) is complicated and costly, and their dispersibility and stability are poor, which limits their application. On the other hand, the bio-based polymer matrix (e.g., ethyl cellulose, starch, carrageenan, etc.) used in bio-based smart packaging materials usually exhibits poor mechanical and barrier properties, which is also not conducive to their practical application. Therefore, the development of low-cost, high-performance bio-based food packaging materials that integrate preservation and freshness monitoring functions has important social and economic benefits in ensuring food quality and safety and avoiding food waste, but it still faces huge challenges at present. Summary of the invention
[0004] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a food packaging material and application that integrates the functions of preservation and freshness monitoring. The present invention utilizes 3-phenyl-2-acrylic acid to react with ferrous sulfate to construct a novel, multifunctional nanofiller, which is used as a functional filler for ethyl cellulose film materials, effectively improving the mechanical strength, toughness, ultraviolet blocking, high-energy short-wave blue light blocking and other properties of the ethyl cellulose film materials, while effectively improving the antibacterial activity, antioxidant activity, pH / ammonia sensitive color change and other functions of the ethyl cellulose film materials, and obtaining a low-cost, comprehensive performance, integrated bio-based food packaging material with preservation and freshness monitoring functions, which has a wide range of application value in the fields of food packaging, intelligent materials, ammonia response materials, pH response materials, antibacterial materials, antioxidant materials, ammonia detection, environmental monitoring and safety.
[0005] Technical solution of the present invention:
[0006] The present invention provides a food packaging material integrating the functions of preservation and freshness monitoring, characterized in that it is composed of the following components in parts by weight: 120 parts of ethyl cellulose, 6 parts of triethyl citrate, and 1.2-4.8 parts of multifunctional nano filler;
[0007] The preparation method of the multifunctional nanofiller comprises the following steps:
[0008] (1) Dissolve 14.81 parts of 3-phenyl-2-acrylic acid in 5000 parts of ethanol and stir at room temperature to obtain a uniform 3-phenyl-2-acrylic acid solution for later use;
[0009] (2) dissolving 13.9 parts of ferrous sulfate heptahydrate in 1000 parts of deionized water to obtain a uniform ferrous sulfate solution for later use;
[0010] (3) Add the ferrous sulfate solution obtained in step (2) to the 3-phenyl-2-propenoic acid solution obtained in step (1), adjust the pH to 6 with 0.2 mol / L sodium hydroxide ethanol solution, stir the reaction at room temperature for 5 min, and then centrifuge, wash and dry in sequence to obtain a multifunctional nanofiller.
[0011] The present invention also provides a method for preparing the above-mentioned food packaging material integrating the functions of freshness preservation and freshness monitoring, which is characterized by comprising the following steps:
[0012] (1) Add 120 parts of ethyl cellulose and 6 parts of triethyl citrate to 4000 parts of ethanol and stir at 55°C for 30 minutes to obtain a uniform blend solution for later use.
[0013] (2) Dispersing 1.2-4.8 parts of the multifunctional nanofiller in 500 parts of ethanol, stirring at room temperature for 10 minutes to obtain a uniform dispersion for later use;
[0014] (3) adding the dispersion obtained in step (2) to the blended solution obtained in step (1), stirring at 55° C. for 30 min to obtain a uniform film-forming solution for later use;
[0015] (4) The film-forming liquid obtained in step (3) is poured into a flat-bottomed glass dish and dried in an oven at 55° C. for 72 hours to obtain a food packaging material with integrated preservation and freshness monitoring functions.
[0016] The application of the food packaging material integrating the functions of preservation and freshness monitoring is characterized by being used in the fields of food packaging, smart materials, biomedicine, ammonia responsive materials, pH responsive materials, ammonia detection, environmental monitoring and safety.
[0017] Compared with the prior art, the present invention has the following beneficial effects:
[0018] The food packaging material with integrated preservation and freshness monitoring functions prepared by the present invention not only has excellent mechanical strength, toughness, ultraviolet blocking, high-energy short-wave blue light blocking and other properties, but also has excellent antibacterial activity, antioxidant activity, pH / ammonia-sensitive color change and other functions, and has important application prospects in the preservation and freshness monitoring of meat (such as shrimp, pork, fish, etc.) food. The material preparation process is simple, environmentally friendly, low-cost, and suitable for large-scale production. It has wide application value in food packaging, smart materials, ammonia responsive materials, pH responsive materials, antibacterial materials, antioxidant active materials, ammonia detection, environmental monitoring and safety and other fields. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1 This is a scanning electron microscope image of the multifunctional nanofiller involved in the present invention;
[0020] Figure 2 The actual pictures are of the ethyl cellulose film prepared in the comparative example of the present invention and the food packaging material sample with integrated preservation and freshness monitoring functions prepared in the example. DETAILED DESCRIPTION
[0021] In order to better explain the present invention, the present invention is further explained in detail below in conjunction with specific examples, but the embodiments of the present invention are not limited thereto.
[0022] In the following specific embodiments and comparative examples, the formulas and preparation methods, the ethyl cellulose used is a product provided by Shanghai MacLean Biochemical Technology Co., Ltd. (article number: E915394-500g); 3-phenyl-2-acrylic acid used is an analytically pure reagent provided by Roan Reagent Co., Ltd. (article number: R014153-100g); triethyl citrate used is an analytically pure reagent provided by Shanghai Yuanye Biotechnology Co., Ltd.; ferrous sulfate heptahydrate is an analytically pure reagent provided by Xilong Science Co., Ltd.; and ethanol is a product provided by Tianjin Fuyu Fine Chemical Co., Ltd.
[0023] In the following specific embodiments and comparative examples, the preparation method of the multifunctional nanofiller comprises the following steps:
[0024] (1) Dissolve 14.81 parts of 3-phenyl-2-acrylic acid in 5000 parts of ethanol and stir at room temperature to obtain a uniform 3-phenyl-2-acrylic acid solution for later use;
[0025] (2) dissolving 13.9 parts of ferrous sulfate heptahydrate in 1000 parts of deionized water to obtain a uniform ferrous sulfate solution for later use;
[0026] (3) The ferrous sulfate solution obtained in step (2) was added to the 3-phenyl-2-propenoic acid solution obtained in step (1), and the pH was adjusted to 6 with 0.2 mol / L sodium hydroxide ethanol solution. The mixture was stirred at room temperature for 5 min, and then centrifuged, washed, and dried to obtain a multifunctional nanofiller (the scanning electron microscopy image of which is shown in FIG. Figure 1 ).
[0027] Example 1
[0028] The food packaging material integrates the functions of preservation and freshness monitoring, characterized in that it is composed of the following components in parts by weight: 120 parts of ethyl cellulose, 6 parts of triethyl citrate, and 1.2 parts of multifunctional nano filler.
[0029] The preparation method comprises the following steps:
[0030] (1) Add 120 parts of ethyl cellulose and 6 parts of triethyl citrate to 4000 parts of ethanol, stir at 55°C for 30 minutes to obtain a uniform blend solution for later use;
[0031] (2) Dispersing 1.2 parts of the multifunctional nanofiller in 500 parts of ethanol, stirring at room temperature for 10 minutes to obtain a uniform dispersion for later use;
[0032] (3) adding the dispersion obtained in step (2) to the blended solution obtained in step (1), stirring at 55° C. for 30 min to obtain a uniform film-forming solution for later use;
[0033] (4) The film-forming liquid obtained in step (3) is poured into a flat-bottomed glass dish and dried in an oven at 55° C. for 72 hours to obtain a food packaging material with integrated preservation and freshness monitoring functions.
[0034] Example 2
[0035] The food packaging material integrates the functions of preservation and freshness monitoring, characterized in that it is composed of the following components in parts by weight: 120 parts of ethyl cellulose, 6 parts of triethyl citrate, and 2.4 parts of multifunctional nano filler.
[0036] The preparation method comprises the following steps:
[0037] (1) Add 120 parts of ethyl cellulose and 6 parts of triethyl citrate to 4000 parts of ethanol, stir at 55°C for 30 minutes to obtain a uniform blend solution for later use;
[0038] (2) Dispersing 2.4 parts of the multifunctional nanofiller in 500 parts of ethanol, stirring at room temperature for 10 minutes to obtain a uniform dispersion for later use;
[0039] (3) adding the dispersion obtained in step (2) to the blended solution obtained in step (1), stirring at 55° C. for 30 min to obtain a uniform film-forming solution for later use;
[0040] (4) The film-forming liquid obtained in step (3) is poured into a flat-bottomed glass dish and dried in an oven at 55° C. for 72 hours to obtain a food packaging material with integrated preservation and freshness monitoring functions.
[0041] Example 3
[0042] The food packaging material integrates the functions of preservation and freshness monitoring, characterized in that it is composed of the following components in parts by weight: 120 parts of ethyl cellulose, 6 parts of triethyl citrate, and 4.8 parts of multifunctional nano filler.
[0043] The preparation method comprises the following steps:
[0044] (1) Add 120 parts of ethyl cellulose and 6 parts of triethyl citrate to 4000 parts of ethanol, stir at 55°C for 30 minutes to obtain a uniform blend solution for later use;
[0045] (2) Dispersing 4.8 parts of the multifunctional nanofiller in 500 parts of ethanol, stirring at room temperature for 10 minutes to obtain a uniform dispersion for later use;
[0046] (3) adding the dispersion obtained in step (2) to the blended solution obtained in step (1), stirring at 55° C. for 30 min to obtain a uniform film-forming solution for later use;
[0047] (4) The film-forming liquid obtained in step (3) is poured into a flat-bottomed glass dish and dried in an oven at 55° C. for 72 hours to obtain a food packaging material with integrated preservation and freshness monitoring functions.
[0048] Comparative Example
[0049] As a comparison standard of the above embodiments, the present invention provides an ethyl cellulose membrane material prepared without the multifunctional nanofiller, comprising the following steps:
[0050] (1) Add 120 parts of ethyl cellulose and 6 parts of triethyl citrate to 4000 parts of ethanol, stir at 55°C for 30 minutes to obtain a uniform blend solution for later use;
[0051] (2) Add 500 parts of ethanol to the blended solution obtained in step (1), and stir at 55° C. for 30 minutes to obtain a uniform film-forming solution for later use;
[0052] (3) The membrane-forming solution obtained in step (2) was poured into a flat-bottomed glass dish and dried in an oven at 55° C. for 72 h to obtain an ethyl cellulose membrane material.
[0053] Performance Test:
[0054] The performance tests were carried out on the ethyl cellulose film material prepared in the above comparative example and the food packaging material with integrated preservation and freshness monitoring functions prepared in the embodiment, wherein the UV-visible performance was tested by using a UV-visible spectrometer, and the average UV transmittance was calculated with reference to GB / T 18830-2009; the tensile performance was tested in accordance with GB / T 1040-2006; the antibacterial property of the material was tested in accordance with QBT2591-2003; the ammonia response test method was as follows: the sample material was exposed to an ammonia environment, and the color change of the sample material was observed; the pH response experimental method was as follows: a buffer solution with a pH value of 10 was dripped on the surface of the material sample prepared in the comparative example and the embodiment, and its color change was observed.
[0055] The DPPH free radical scavenging experimental method is as follows:
[0056] In the experimental group, 0.2 g of the membrane sample was cut into pieces and soaked in 5 mL of ethanol. After soaking for 24 h, 2 mL of the supernatant of the soaking solution was extracted and set aside. Then, 1 ml of 50 mg / L DPPH solution was added to the 2 mL of the supernatant, and the mixture was shaken and placed in the dark at room temperature for 1 h. Then, the absorbance of the mixture at 517 nm (denoted as A) was measured using an ultraviolet spectrophotometer. sample); for the control group, 1 mL of 50 mg / L DPPH solution was added to 2 mL of ethanol, and the mixture was shaken and placed in the dark at room temperature for 1 h; then, the absorbance of the mixture at 517 nm (denoted as A) was measured by a UV spectrophotometer. control );DPPH free radical scavenging rate (%)=100*(A control -A sample ) / A control .
[0057] Shrimp freshness monitoring experiment: Fresh shrimps were purchased from the market, and the shrimps (mass: 30 g) were placed in a glass culture dish and sealed with a culture dish lid. The materials prepared in the comparative example and Example 3 (pre-cut into sample materials with a diameter of 1.2 cm) were pasted under the lid. The shrimp samples were then stored in an oven at 25°C, and the changes in the freshness of the shrimps and the color changes of the sample materials were observed and recorded.
[0058] The above performance test data are shown in Table 1 and Table 2.
[0059] Table 1 Sample performance test data
[0060]
[0061] Table 2 Shrimp freshness monitoring experiment results (where t is the storage time of fresh shrimp)
[0062]
[0063] The results of the ammonia response test show that the material prepared in the comparative example is colorless and transparent. After being exposed to an ammonia environment, its color does not change, and it still presents colorless and transparent optical properties; the material prepared in Example 1 is light yellow, and after being exposed to an ammonia environment, its color changes to light brown; the material prepared in Example 2 is light yellow, and after being exposed to an ammonia environment, its color changes to light brown; the material prepared in Example 3 is yellow, and after being exposed to an ammonia environment, its color changes to brown. The above results show that the materials prepared in the embodiments of the present invention have the function of color change in response to ammonia.
[0064] The results of the pH response experiment show that after a buffer solution with a pH value of 10 was added to the surface of the material prepared in the comparative example, its color did not change significantly; after a buffer solution with a pH value of 10 was added to the surface of the material prepared in Example 3, its color changed significantly (from yellow to brown). The above results show that the material prepared in the example of the present invention has a pH response color change function.
[0065] The results of the DPPH free radical scavenging experiment show that the ethyl cellulose film material prepared in the comparative example has no obvious antioxidant activity, while the food packaging material with integrated preservation and freshness monitoring functions prepared in Example 3 has a DPPH free radical scavenging rate of 57.72%, that is, the material prepared in the example has excellent antioxidant activity.
[0066] The results of the antibacterial test experiments show that the ethyl cellulose film material prepared in the comparative example does not show obvious antibacterial activity against Escherichia coli and Staphylococcus aureus, while the food packaging material with integrated preservation and freshness monitoring functions prepared in Example 3 has an inhibition rate of more than 99% against Escherichia coli and Staphylococcus aureus, that is, the material prepared in the example has excellent antibacterial activity.
[0067] In summary, it can be seen from the sample performance test data (see Tables 1 and 2) that the food packaging material with integrated preservation and freshness monitoring functions prepared by the present invention not only has excellent mechanical strength, toughness, UV blocking, high-energy short-wave blue light blocking and other properties, but also has excellent antibacterial activity, antioxidant activity, pH / ammonia sensitive color change and other functions. It has great application potential in food preservation, and can be used as an intelligent indicator material to timely and effectively indicate the freshness changes of meat foods (such as shrimp, pork, fish, etc.) during storage (see Table 2). It has wide application value in food packaging, intelligent materials, ammonia response materials, pH response materials, antibacterial materials, antioxidant active materials, ammonia detection, environmental monitoring and safety and other fields.
[0068] The content of the present invention is not limited to the embodiments listed, and any equivalent changes made to the technical solution of the present invention by ordinary technicians in this field after reading the description of the present invention are covered by the claims of the present invention.
Claims
1. A food packaging material integrating the functions of preservation and freshness monitoring, characterized in that: The invention is composed of the following components in parts by weight: 120 parts of ethyl cellulose, 6 parts of triethyl citrate, and 1.2-4.8 parts of multifunctional nanofiller; The preparation method of the multifunctional nanofiller comprises the following steps: (1) Dissolve 14.81 parts of 3-phenyl-2-acrylic acid in 5000 parts of ethanol and stir at room temperature to obtain a uniform 3-phenyl-2-acrylic acid solution for later use; (2) dissolving 13.9 parts of ferrous sulfate heptahydrate in 1000 parts of deionized water to obtain a uniform ferrous sulfate solution for later use; (3) Add the ferrous sulfate solution obtained in step (2) to the 3-phenyl-2-propenoic acid solution obtained in step (1), adjust the pH to 6 with 0.2 mol / L sodium hydroxide ethanol solution, stir the reaction at room temperature for 5 min, and then centrifuge, wash and dry in sequence to obtain a multifunctional nanofiller.
2. The method for preparing a food packaging material integrating freshness preservation and freshness monitoring functions according to claim 1, characterized in that The steps include: (1) Add 120 parts of ethyl cellulose and 6 parts of triethyl citrate to 4000 parts of ethanol, stir at 55°C for 30 minutes to obtain a uniform blend solution for later use; (2) Dispersing 1.2-4.8 parts of the multifunctional nanofiller in 500 parts of ethanol, stirring at room temperature for 10 minutes to obtain a uniform dispersion for later use; (3) adding the dispersion obtained in step (2) to the blended solution obtained in step (1), stirring at 55° C. for 30 min to obtain a uniform film-forming solution for later use; (4) The film-forming liquid obtained in step (3) is poured into a flat-bottomed glass dish and dried in an oven at 55° C. for 72 hours to obtain a food packaging material with integrated preservation and freshness monitoring functions.
3. The use of the food packaging material integrating the functions of preservation and freshness monitoring according to claim 1, characterized in that: Used in food packaging, smart materials, ammonia responsive materials, pH responsive materials, ammonia detection, environmental monitoring and safety fields.