A preservative film with antibacterial efficacy and a preparation process thereof
By adding curcumin and chlorogenic acid nanoparticles to plastic wrap and combining them with proteins, the problem of insufficient antibacterial properties of existing plastic wrap is solved. This achieves highly efficient antibacterial activity and extended antibacterial duration under light conditions, and the material is safe and harmless.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- JIANGSU JIEYA HOMEWARE CO LTD
- Filing Date
- 2025-07-16
- Publication Date
- 2026-07-24
AI Technical Summary
Existing plastic wraps have insufficient antibacterial properties, especially under light conditions, making them unstable and unable to effectively inhibit the growth of microorganisms in food. Furthermore, traditional plastic wraps are not easily degraded and are harmful to the environment.
By adding curcumin and chlorogenic acid to plastic wrap, nanoparticles are prepared using nanoemulsion technology and combined with proteins to form a stable antibacterial agent, improving the photostability and sustained-release effect of curcumin. Antibacterial plastic wrap is then produced by blowing film using materials such as polyethylene.
It significantly improves the antibacterial properties of plastic wrap, prolongs the antibacterial duration, and maintains a highly effective antibacterial effect, especially under light conditions. The material is safe and harmless, and has good biocompatibility and slow-release properties.
Smart Images
Figure CN120623616B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of packaging materials, and in particular to a food preservation film with antibacterial function and its preparation process. Background Technology
[0002] Plastic wrap, as an important material for food packaging, primarily functions to protect food, extend its shelf life, and maintain its freshness. Currently, plastic wrap on the market is mainly divided into two categories: traditional plastic wrap and new biodegradable plastic wrap. Traditional plastic wrap, such as polyethylene (PE) film, while inexpensive, suffers from poor biodegradability and poses a potential threat to the environment. New biodegradable plastic wrap, such as those based on polysaccharides, proteins, and lipids, features widely available raw materials, is non-toxic and harmless, and is environmentally friendly, making it a viable alternative to non-biodegradable plastic wrap.
[0003] Traditional plastic wrap primarily protects food through physical isolation, but it is not effective in inhibiting bacterial growth.
[0004] Therefore, it is necessary to develop food preservation films with stronger antibacterial properties to effectively inhibit the growth and reproduction of microorganisms in food and extend the shelf life of food. At the same time, how to extend the antibacterial duration of food preservation films and how to ensure that food preservation films still play an antibacterial role under the influence of light are important issues that need to be solved at present. Summary of the Invention
[0005] To address the problem of insufficient antibacterial efficacy of existing plastic wrap, this invention provides an antibacterial plastic wrap. By adding a stabilizer, the photostability of curcumin is improved, thereby increasing the antibacterial duration and antibacterial performance of the plastic wrap under strong light.
[0006] The technical solution adopted in this invention is as follows:
[0007] An antibacterial plastic wrap comprising the following components: curcumin, chlorogenic acid, protein, and a plastic wrap substrate.
[0008] Furthermore, the substrate of the cling film is selected from: polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), polymethylpentene (PMP), or combinations thereof. Preferably, the substrate of the cling film is polyethylene (PE).
[0009] Furthermore, the protein is selected from: soy protein isolate (SPI), zein, wheat gluten, whey protein, casein, or combinations thereof. Preferably, the protein is zein.
[0010] Furthermore, curcumin and chlorogenic acid are mixed with proteins and prepared into nanoparticles using nanoemulsion technology.
[0011] Furthermore, the mass ratio of curcumin, chlorogenic acid, protein, and cling film substrate is 1-2:2-4:5-10:500-1000. Preferably, the mass ratio of curcumin, chlorogenic acid, protein, and cling film substrate is 1:2:5:500.
[0012] This invention provides a process for preparing a food preservation film with antibacterial properties, comprising the following steps:
[0013] Preparation of nanoparticles
[0014] Dissolve 1 gram of curcumin and 2 grams of chlorogenic acid in 100 ml of water to obtain a solution;
[0015] Dissolve 5 grams of protein in the above solution and sonicate for 30 minutes to obtain a mixed solution;
[0016] The mixed solution was processed by a high-pressure homogenizer to obtain particles with a diameter of 100-200 nanometers.
[0017] Preparation of plastic wrap
[0018] The above nanoparticles were mixed with 500 grams of polyethylene and added to a blown film machine;
[0019] An antibacterial preservation film with a thickness of 10-15 micrometers (μm) was obtained by blowing the film at 200℃.
[0020] Furthermore, the thickness of the plastic wrap can be selected from 10 micrometers, 12 micrometers, and 15 micrometers.
[0021] Compared with the prior art, the beneficial effects of the present invention are as follows:
[0022] 1. Enhanced antibacterial properties: Curcumin, as a photosensitizer, can generate reactive oxygen species under light conditions, effectively inhibiting the growth of microorganisms and improving the antibacterial properties of the plastic wrap.
[0023] 2. Improved stability of curcumin: The addition of chlorogenic acid significantly improved the photostability of curcumin and prolonged its half-life under light conditions.
[0024] 3. Enhanced food safety: Since curcumin and chlorogenic acid are both natural ingredients, the food preservation film of this invention has good biocompatibility and food safety.
[0025] 4. Protein Addition: 1) Improved Solubility: Zeadrin can bind to curcumin through non-covalent interactions, forming a stable nanocomplex, thus significantly improving the water solubility of curcumin. 2) Sustained-Release Effect: Protein-based nanoparticles provide a sustained-release effect, controlling the release rate of curcumin and prolonging the action time of the antibacterial preservative film. 3) Enhanced Oxidative Stability: Nano-encapsulated curcumin exhibits better oxidative stability than curcumin alone, mainly due to the protein's shielding effect on curcumin and the protein's strong antioxidant properties. Attached Figure Description
[0026] Figure 1 The inhibitory effect of the plastic wraps prepared for different embodiments on Escherichia coli at different times.
[0027] Figure 2 The inhibitory effect of the plastic wraps prepared for different embodiments on Staphylococcus aureus at different times.
[0028] Figure 3 The inhibitory effect of the plastic wraps prepared for different embodiments on Escherichia coli over time under strong light. Detailed Implementation
[0029] The present invention will be further illustrated below with specific embodiments and comparative examples. It should be understood that these embodiments and comparative examples are only for more detailed and specific illustration, and should not be construed as limiting the present invention in any way.
[0030] Example 1
[0031] An antibacterial food preservation film contains the following components: curcumin, chlorogenic acid, zein, and polyethylene (PE), wherein the mass ratio of the above components is 1:2:5:500.
[0032] The preparation method of plastic wrap is as follows:
[0033] Preparation of nanoparticles
[0034] Dissolve 1 gram of curcumin and 2 grams of chlorogenic acid in 100 ml of water to obtain a solution;
[0035] Dissolve 5 grams of protein (zein) in the above solution and sonicate for 30 minutes to obtain a mixed solution;
[0036] The mixed solution was processed by a high-pressure homogenizer to obtain particles with a diameter of 100-200 nanometers;
[0037] Preparation of plastic wrap
[0038] The above nanoparticles were mixed with 500 grams of polyethylene and added to a blown film machine;
[0039] An antibacterial preservation film with a thickness of 12 micrometers (μm) was obtained by blowing the film at 200℃.
[0040] Example 2
[0041] An antibacterial food preservation film contains the following components: curcumin, zein, and polyethylene (PE), wherein the mass ratio of the above components is 1:5:500.
[0042] Dissolve 1 gram of curcumin in 100 ml of water to obtain a solution;
[0043] Dissolve 5 grams of protein (zein) in the above solution and sonicate for 30 minutes to obtain a mixed solution;
[0044] The mixed solution was processed by a high-pressure homogenizer to obtain particles with a diameter of 100-200 nanometers;
[0045] Preparation of plastic wrap
[0046] The above nanoparticles were mixed with 500 grams of polyethylene and added to a blown film machine;
[0047] An antibacterial preservation film with a thickness of 12 micrometers (μm) was obtained by blowing the film at 200℃.
[0048] Example 3
[0049] An antibacterial food preservation film comprising the following components: curcumin, chlorogenic acid, and polyethylene (PE), wherein the mass ratio of the above components is 1:2:500.
[0050] The preparation method of plastic wrap is as follows:
[0051] Preparation of nanoparticles
[0052] Dissolve 1 gram of curcumin and 2 grams of chlorogenic acid in 100 ml of water to obtain a solution;
[0053] The above solution was processed by a high-pressure homogenizer to obtain particles with a diameter of 100-200 nanometers;
[0054] Preparation of plastic wrap
[0055] The above nanoparticles were mixed with 500 grams of polyethylene and added to a blown film machine;
[0056] An antibacterial preservation film with a thickness of 12 micrometers (μm) was obtained by blowing the film at 200℃.
[0057] Example 1: Antibacterial duration test
[0058] Test samples: The plastic wrap prepared in Examples 1-3 was used as the experimental group, and the plastic wrap prepared directly from polyethylene (i.e., without any added components other than polyethylene) was used as the control group.
[0059] Bacterial strain selection: Escherichia coli and Staphylococcus aureus were tested respectively.
[0060] Strain activation and preparation: The standard test strain was inoculated onto nutrient agar (NA) slant medium and cultured at (37±1)℃ for 24 hours, then transferred to fresh slant medium and cultured at (35±1)℃ for 20 hours. A 1 / 500 concentration of NB medium was prepared, and the activated strain was transferred into the NB medium to achieve a concentration of approximately 10... 8 -10 9 CFU / mL bacterial suspension.
[0061] Sample preparation: Cut the plastic wrap sample to be tested into 2cm × 2cm pieces, and evenly spread the prepared bacterial suspension on the plastic wrap sample to ensure that the entire sample surface is covered.
[0062] Culture and elution: The inoculated samples were placed in a constant temperature and humidity incubator and cultured at (37±1)℃. After 24 hours of culture, the bacteria were eluted from the samples by vigorous shaking with physiological saline.
[0063] Viable cell count and antimicrobial rate calculation: After appropriate dilution of the eluent, spread it on an agar plate and incubate. Count the colonies after incubation. Calculate the antimicrobial rate using the following formula:
[0064] Antibacterial rate = [(number of colonies in control group - number of colonies in test group) / number of colonies in control group] × 100%
[0065] Test data: The antibacterial rate was tested at the initial stage and at 1, 2, 3, 4, 5, 6, 7, and 8 months. All the plastic wraps were stored under the same indoor, non-light-exposed environment. Each group was tested three times, and the average value was used for calculation. Test results are shown below. Figure 1 and Figure 2 .
[0066] Conclusion: Based on Figure 1 It can be seen that the preservation film prepared in Example 1 maintained an inhibition rate of 95%-100% against Escherichia coli from the initial test to the 8-month test period, showing excellent long-term inhibition effect.
[0067] The preservation film prepared in Example 3 lacked protein groups, and its effectiveness against Escherichia coli decreased rapidly starting from the third month. By the eighth month, its antibacterial rate was only about 10%. This indicates that the lack of protein-based zein caused curcumin to be released rapidly. This further demonstrates that protein-based zein can provide a sustained-release effect, control the release rate of curcumin, and prolong the action time of the antibacterial preservation film.
[0068] The antibacterial rate of the plastic wrap prepared in Example 2 decreased to below 90% starting from the 5th month. This indicates that although the above experiment was conducted in an indoor, non-light-exposed environment, the presence of weak light indoors, coupled with the lack of chlorogenic acid, led to the decomposition of curcumin under weak light. Therefore, Example 2 shows that the addition of chlorogenic acid significantly improved the photostability of curcumin and extended its half-life under light conditions.
[0069] Figure 2 It is the inhibitory effect on Staphylococcus aureus, and its inhibitory effect is similar to... Figure 1 The inhibitory effects on Escherichia coli showed similar trends, but the inhibition rates against Staphylococcus aureus and Escherichia coli differed.
[0070] Example 2: The effect of light on the inhibitory effect of plastic wrap
[0071] Test samples: The plastic wrap prepared in Examples 1-3 was used as the experimental group, and the plastic wrap directly prepared from polyethylene was used as the control group. Bacterial strain: *Escherichia coli*. Other preparation steps are detailed in Example 1.
[0072] Test data: Antibacterial rates were tested on the initial, 2nd, 4th, 6th, 10th, 15th, and 20th days. The plastic wrap was exposed to 8000 lux of light for 6 hours daily. Each group was tested three times, and the average value was used for calculation. Test results are shown below. Figure 3 .
[0073] Conclusion: Based on Figure 3 It can be seen that the inhibition rate of the plastic wrap prepared in Example 1 against Escherichia coli under strong light remained above 90% from the initial stage to the 20-day test period. This means that the addition of chlorogenic acid significantly improved the photostability of curcumin and extended its half-life under light conditions.
[0074] The inhibition rate of the plastic wrap prepared in Example 2 against Escherichia coli under strong light decreased significantly from day 4, and by day 20, the inhibition rate was less than 10%, indicating that curcumin is extremely unstable under strong light conditions.
[0075] The inhibition rate of the cling film prepared in Example 3 against Escherichia coli under strong light began to decline from day 6, and by day 20, the inhibition rate was only about 50%. It can be seen that although chlorogenic acid can improve the photostability of curcumin, due to the lack of protein groups, curcumin is released faster under strong light, resulting in a rapid decrease in the content of curcumin.
[0076] This shows that curcumin, as a photosensitizer, can generate reactive oxygen species under light conditions, effectively inhibiting microbial growth and improving the antibacterial properties of plastic wrap.
[0077] The addition of chlorogenic acid significantly improved the photostability of curcumin and prolonged its half-life under light conditions.
[0078] Protein-based nanoparticles can provide a sustained-release effect, control the release rate of curcumin, and prolong the action time of antibacterial plastic wrap.
[0079] Modifications and variations to this invention can be made by those skilled in the art without departing from its scope. Furthermore, it should be understood that aspects of the various embodiments can be interchanged entirely or partially. The foregoing description is also exemplary only and is not intended to limit the invention further described in the appended claims.
Claims
1. A plastic wrap with antibacterial properties, comprising the following components: curcumin, chlorogenic acid, protein, and a plastic wrap substrate; The substrate of the cling film is selected from: polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), polymethylpentene (PMP) or a combination thereof; in, The protein was selected from zein. The mass ratio of curcumin, chlorogenic acid, protein and plastic wrap substrate is 1-2 : 2-4 : 5-10 : 500-1000.
2. The food preservation film according to claim 1, wherein, The substrate of the cling film is selected from polyethylene (PE).
3. The food preservation film according to claim 1, wherein, The mass ratio of curcumin, chlorogenic acid, protein and plastic wrap substrate is 1:2:5:
500.
4. The food preservation film according to claim 1, comprising the following preparation steps: Preparation of nanoparticles Dissolve 1 gram of curcumin and 2 grams of chlorogenic acid in 100 ml of water to obtain a solution; Dissolve 5 grams of protein in the above solution and sonicate for 30 minutes to obtain a mixed solution; The mixed solution was processed by a high-pressure homogenizer to obtain particles with a diameter of 100-200 nanometers; Preparation of plastic wrap The above nanoparticles were mixed with 500 grams of polyethylene and added to a blown film machine; Film blowing at 200℃ yields antibacterial preservation films with a thickness between 10 and 15 micrometers (μm); the preservation films are prepared in three thicknesses: 10 micrometers, 12 micrometers, and 15 micrometers.
5. The method for preparing the plastic wrap according to any one of claims 1-4, comprising the following preparation steps: Preparation of nanoparticles Dissolve 1 gram of curcumin and 2 grams of chlorogenic acid in 100 ml of water to obtain a solution; Dissolve 5 grams of protein in the above solution and sonicate for 30 minutes to obtain a mixed solution; The mixed solution was processed by a high-pressure homogenizer to obtain particles with a diameter of 100-200 nanometers; Preparation of plastic wrap The above nanoparticles were mixed with 500 grams of polyethylene and added to a blown film machine; Film blowing at 200℃ yields antibacterial preservation films with a thickness between 10 and 15 micrometers (μm); the preservation films are prepared in three thicknesses: 10 micrometers, 12 micrometers, and 15 micrometers.