Cinnamomum camphora essential oil microcapsule antibacterial preservative paper as well as preparation method and application thereof

Abstract

The invention relates to the technical field of agricultural product preservation, in particular to cinnamomum camphora essential oil microcapsule antibacterial preservative paper as well as a preparation method and application thereof. The specific preparation method comprises the following steps: uniformly mixing a cinnamomum camphora essential oil microcapsule with a polyethylene glycol solution to obtain a cinnamomum camphora essential oil microcapsule coating liquid; and coating the surface of a paper-based material with the cinnamomum camphora essential oil microcapsule coating liquid, and drying to obtain the cinnamomum camphora essential oil microcapsule antibacterial preservative paper. The polyethylene glycol solution is prepared by mixing polyethylene glycol 600 and polyethylene glycol 8000 according to a mass ratio of 1: 2. Cinnamomum camphora essential oil is mainly used as plant essential oil, and the ratio of polyethylene glycol 600 to polyethylene glycol 8000 is adjusted, so that the contact effect of the cinnamomum camphora essential oil microcapsule antibacterial preservative paper and the surfaces of fruits and vegetables is promoted, an effective preservative layer is formed, a more stable and more lasting preservative film can be formed, and the shelf life is further prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of agricultural product preservation, and particularly relates to a camphor essential oil microcapsule antibacterial preservation paper and its preparation method and application. Background Art

[0002] Nowadays, with the continuous enhancement of people's food safety awareness, synthetic antioxidants and preservative fungicides are increasingly rejected by the public. Therefore, it is of great practical significance to search for and study green, safe, stable and efficient plant-derived natural antioxidants and preservative fungicides.

[0003] In the aspect of fruit and vegetable preservation, the commonly used preservation methods are low-temperature preservation and spraying preservatives. However, the low-temperature preservation method has high energy consumption; spraying preservatives has poor effects on fruits and vegetables with hairy surfaces. Therefore, it is urgent to find an environmentally friendly, healthy and green preservation method. For example, kiwifruit is rich in nutrients and has a huge annual production and sales volume, but it is easily damaged mechanically during the picking process and spoils very seriously during storage. Kiwifruit belongs to berry fruits, has a strong respiration rate, and is easily infected by microorganisms, causing spoilage and resulting in commercial and economic losses. Therefore, the research on the preservation method for kiwifruit and other fruits and vegetables is crucial.

[0004] Plant essential oils are deeply favored by consumers due to their natural, green and environmentally friendly characteristics. Plant essential oils have diverse components and have good anti-inflammatory, antibacterial, antioxidant and other activities. Currently, they are widely used in the food, biological medicine and cosmetics industries. However, liquid essential oils are unstable, volatile, and easily affected by external factors such as light, temperature, and oxygen, which restricts their application in the field of food preservation. Therefore, through the microencapsulation process of plant essential oils, researchers can form a strong "partition" between the essential oil and the external environment, protect the essential oil from the influence of factors such as humidity, pH value, and oxidation, and can also play a certain role in modifying the function of the essential oil to ensure the effective release of its active ingredients.

[0005] For example, some researchers have added powdered plant essential oil microcapsule materials to paper-based materials or membrane materials to obtain plant essential oil microcapsule paper-based materials or membrane materials. Through this technology, not only can the problems of difficult placement and poor preservation of powdered microcapsule materials be solved, but also the scope of application for preservation can be broadened.

[0006] However, traditionally, when preparing plant essential oil microcapsule paper-based materials or membrane materials, due to the improper selection of paper-based materials or membrane materials, the adhesion between the plant essential oil microcapsules and the paper-based materials or membrane materials is poor, and they are easily detached on the surface. In addition, the contact between the formed plant essential oil microcapsule paper-based materials or membrane materials and the surface of fruits and vegetables is not good, resulting in unsatisfactory preservation effects. Summary of the Invention

[0007] To solve the problems of poor adhesion between the above-mentioned plant essential oil microcapsules and paper-based materials or membrane materials and poor freshness preservation effect, the present invention provides a camphor essential oil microcapsule antibacterial freshness preservation paper, its preparation method and application.

[0008] To achieve the above object, the technical solution of the present invention is as follows.

[0009] The first aspect of the present invention provides a preparation method of a camphor essential oil microcapsule antibacterial freshness preservation paper, comprising the following steps:

[0010] Mix the camphor essential oil microcapsules evenly with a polyethylene glycol solution to obtain a camphor essential oil microcapsule coating solution; coat the camphor essential oil microcapsule coating solution on the surface of the paper-based material, and after drying, obtain the camphor essential oil microcapsule antibacterial freshness preservation paper; the polyethylene glycol solution is prepared by mixing polyethylene glycol 600 and polyethylene glycol 8000 in a mass ratio of 1:2.

[0011] The present invention mainly uses camphor essential oil as the plant essential oil, and by adjusting the ratio of polyethylene glycol 600 and polyethylene glycol 8000, the prepared camphor essential oil microcapsule antibacterial freshness preservation paper has good wettability, promotes the contact effect between the camphor essential oil microcapsule antibacterial freshness preservation paper and the surface of fruits and vegetables, and forms an effective freshness preservation layer. At the same time, by adding polyethylene glycol 8000 with a larger molecular weight, a more stable and lasting fresh-keeping film can be formed, further extending the freshness preservation time.

[0012] In the present invention, under the condition that the mass ratio of polyethylene glycol 600 and polyethylene glycol 8000 is 1:2, polyethylene glycol 600 and polyethylene glycol 8000 exhibit excellent performance in terms of viscosity, surface tension, and interaction with camphor essential oil microcapsules.

[0013] Preferably, the mass fraction of the camphor essential oil microcapsules in the camphor essential oil microcapsule coating solution is 1% - 3%.

[0014] In the present invention, the concentration of the camphor essential oil microcapsules is selected because camphor essential oil contains various chemical components, and excessive use may have negative effects. Although the microcapsule technology can slow down the release, excessive use may still increase the residue risk and affect food safety. And an appropriate amount of camphor essential oil microcapsules can effectively inhibit the growth of microorganisms and extend the freshness preservation period. However, excessive addition may lead to too high an essential oil concentration on the surface of kiwifruit, affecting its natural metabolism and accelerating spoilage instead.

[0015] Preferably, the camphor essential oil microcapsules are prepared by the molecular embedding method with β-cyclodextrin as the wall material and camphor essential oil as the core material.

[0016] Preferably, the camphor essential oil microcapsules are prepared by the following method:

[0017] Dissolve camphor essential oil in an alcohol solvent to obtain a camphor essential oil alcohol solution; dissolve β-cyclodextrin in water to obtain a saturated β-cyclodextrin solution; add the camphor essential oil alcohol solution to the saturated β-cyclodextrin solution, stir and embed for 2 h to 3 h, then let it stand at 0 °C to 4 °C for 12 h to 24 h, filter, collect the solid matter, and freeze-dry to obtain camphor essential oil microcapsules.

[0018] Preferably, the mass ratio of the camphor essential oil to the alcohol solvent is 1:15 to 20.

[0019] Preferably, the mass ratio of the camphor essential oil alcohol solution to the saturated β-cyclodextrin solution is 1:6 to 9.

[0020] Preferably, the temperature at which β-cyclodextrin is dissolved in water is 60 °C to 70 °C.

[0021] Preferably, when preparing the camphor essential oil microcapsules, the temperature is 50 °C, the stirring rate is 1000 r / min, and the stirring and embedding time is 2 h to 3 h.

[0022] Preferably, the paper-based material is filter paper.

[0023] In the second aspect of the present invention, there is provided a camphor essential oil microcapsule antibacterial fresh-keeping paper, which is prepared by using the preparation method of the camphor essential oil microcapsule antibacterial fresh-keeping paper described in the first aspect.

[0024] In the third aspect of the present invention, there is provided an application of the camphor essential oil microcapsule antibacterial fresh-keeping paper as a fresh-keeping material for fruits and vegetables, and the camphor essential oil microcapsule antibacterial fresh-keeping paper is the camphor essential oil microcapsule antibacterial fresh-keeping paper described in the second aspect.

[0025] Preferably, the application of the camphor essential oil microcapsule antibacterial fresh-keeping paper as a fresh-keeping material for fruits and vegetables is for inhibiting Penicillium or spoilage bacteria. The spoilage bacteria are at least one of Escherichia coli and Staphylococcus aureus.

[0026] Preferably, the application of the camphor essential oil microcapsule antibacterial fresh-keeping paper as a fresh-keeping material for fruits and vegetables is for inhibiting Penicillium or spoilage bacteria on the surface of fruits and vegetables.

[0027] Preferably, the application of the camphor essential oil microcapsule antibacterial fresh-keeping paper as a fresh-keeping material for fruits and vegetables is for the fresh-keeping of fruits and vegetables. For example, the fruits and vegetables are kiwifruit or cherry tomatoes.

[0028] Advantages of the present invention:

[0029] 1. The present invention mainly uses camphor essential oil as the plant essential oil. By adjusting the ratio of polyethylene glycol 600 and polyethylene glycol 8000, the prepared camphor essential oil microcapsule antibacterial fresh-keeping paper has good wettability, promotes the contact effect between the camphor essential oil microcapsule antibacterial fresh-keeping paper and the surface of fruits and vegetables, and forms an effective fresh-keeping layer. At the same time, by adding polyethylene glycol 8000 with a larger molecular weight, a more stable and more durable fresh-keeping film can be formed, further extending the fresh-keeping time.

[0030] 2. The method of the present invention can maintain the stability of camphor essential oil while also exerting antibacterial, antioxidant and other activities, effectively maintaining the quality indexes such as texture, color and nutritional components of post-harvest fruits and vegetables such as kiwifruit, and enhancing the added value of the kiwifruit and other fruit and vegetable industries. Brief Description of the Drawings

[0031] Figure 1 It is the antibacterial effect diagram of the camphor essential oil prepared in Example 1 of the present invention against Penicillium. Among them, (a) is the antibacterial effect diagram of Penicillium in the control group; (b)-(d) are the antibacterial effect diagrams of three experimental groups against Penicillium.

[0032] Figure 2 It is the thermal stability analysis result diagram of the camphor essential oil microcapsule prepared in Example 1. Among them, (a) is the TG curve of the camphor essential oil and the camphor essential oil microcapsule prepared in Example 1; (b) is the DTG curve of the camphor essential oil and the camphor essential oil microcapsule prepared in Example 1. The full English name of the TG curve is Thermogravimetric Curve, and the Chinese name is the thermogravimetric curve. The full English name of the DTG curve is Derivative Thermogravimetric Curve, and the Chinese name is the derivative thermogravimetric curve.

[0033] Figure 3 It is the slow-release performance analysis result diagram of the camphor essential oil microcapsule prepared in Example 1.

[0034] Figure 4 It is the picture of the appearance change of kiwifruit with different treatments over the storage time.

[0035] Figure 5 It is the chromaticity change curve of kiwifruit with different treatments over the storage time.

[0036] Figure 6 It is the weight loss rate change curve of kiwifruit with different treatments over the storage time.

[0037] Figure 7 It is the hardness change curve of kiwifruit with different treatments over the storage time.

[0038] Figure 8 It is the soluble solid change curve of kiwifruit with different treatments over the storage time.

[0039] Figure 9 The titratable acid content change curves of kiwifruits under different treatments over storage time.

[0040] Figure 10 The vitamin C content change curves of kiwifruits under different treatments over storage time.

[0041] Figure 11 The malondialdehyde content change curves of kiwifruits under different treatments over storage time. Detailed implementation manners

[0042] In order to make the objectives, technical solutions and advantages of the present invention more clear and understandable, the present invention will be further described in detail below in conjunction with embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0043] Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0044] In the present invention, camphor essential oil is a natural plant essential oil extracted from camphor leaves. Its main components include camphor aldehyde, eugenol, etc., and it has anti-inflammatory, antibacterial and antioxidant activities, and has relatively wide applications in the biomedical and food industries. However, camphor essential oil has a strong odor, is volatile and unstable, and is easily affected by adverse environments and extraction technologies, especially high temperature and oxidation, which can cause up to 90% degradation of volatile components, limiting its application in food preservation. At present, technologies such as microcapsule coating or solubilization emulsification can be used to improve the stability and applicability of essential oils. The microcapsule technology is to encapsulate camphor essential oil with wall materials for protection, which can effectively isolate the essential oil from contact with the external environment and reduce volatilization and decomposition caused by factors such as oxygen, light and heat. It is one of the common methods to increase the stability of essential oils and achieve more controllable delivery and release, and is suitable for food preservation.

[0045] Polyethylene glycol 600 (PEG-600) has good water solubility and wettability, which can help the preservative paper better contact with the surface of fruits and vegetables to form an effective preservative layer. And it has certain lubricity and softness, which can improve the coating performance and feel of the preservative paper. Polyethylene glycol 8000 (PEG-8000) has a larger molecular weight and higher viscosity, and can form a more stable and lasting preservative film. It has good physiological inertness and mildness, and will not cause obvious irritation or toxic reaction to the human body, and is suitable for food preservation. Therefore, an antibacterial preservative paper with good preservation effect can be prepared by using this preparation.

[0046] The present invention mainly uses camphor essential oil as the plant essential oil. By adjusting the ratio of polyethylene glycol 600 and polyethylene glycol 8000, the prepared camphor essential oil microcapsule antibacterial fresh-keeping paper has better wettability, promotes the contact effect between the camphor essential oil microcapsule antibacterial fresh-keeping paper and the surface of fruits and vegetables, and forms an effective fresh-keeping layer. At the same time, by adding polyethylene glycol 8000 with a larger molecular weight, a more stable and longer-lasting fresh-keeping film can be formed, further extending the fresh-keeping time.

[0047] The natural plant essential oil (camphor essential oil) provided by the present invention has good biological activity. Using the essential oil as the core material to prepare essential oil microcapsules can effectively isolate the contact between the essential oil and the external environment, and reduce the volatilization and decomposition of the essential oil caused by oxygen, light, heat, etc. This method is one of the common methods to enhance the stability of essential oils and achieve more controllable delivery and release, and can be effectively used for food preservation. At the same time, when in use, the essential oil microcapsules can be slowly released and play an antibacterial and antioxidant effect, extending the storage time of post-harvest kiwifruit and maintaining the quality of the stored kiwifruit during the storage period.

[0048] The raw materials used in the camphor essential oil microcapsule fresh-keeping paper in the present invention are widely sourced and inexpensive, suitable for large-scale production, and the relevant raw materials are non-toxic to the human body, with guaranteed safety. In addition, the essential oil microcapsule fresh-keeping paper of the present invention has stable self-performance and can be stored for a long time without damaging the packaging, and has broad application prospects in the field of fruit fresh-keeping (especially in kiwifruit fresh-keeping).

[0049] The present invention prepares the camphor essential oil into a microencapsulated antibacterial fresh-keeping paper. Microencapsulating the essential oil can further improve the stability and antibacterial and bactericidal activities of the camphor essential oil, effectively maintain the quality indexes such as the texture, color, and nutritional components of post-harvest fresh kiwifruit, not only increasing the added value of the kiwifruit industry but also making up for the deficiencies in the key technologies of post-harvest storage and transportation of kiwifruit, which has important theoretical and practical significance.

[0050] The technical solution of the present invention will be further described below through specific embodiments.

[0051] In the following embodiments, unless otherwise specified, the methods are all conventional methods; the reagents and materials, unless otherwise specified, can all be purchased on the market.

[0052] Example 1

[0053] A preparation method of camphor essential oil microcapsule antibacterial fresh-keeping paper includes the following steps:

[0054] Step 1, extraction of camphor essential oil:

[0055] Add 10 g of crushed camphor leaves and 60 mL of distilled water to the essential oil hydrosol extraction equipment and heat it using an induction cooker. First, heat to boiling at 2000 watts, then adjust to 1500 watts, turn on the cooling water in the condenser, and continue distilling until no essential oil is precipitated. Collect the distillate to obtain camphor essential oil; among them, the extraction rate of camphor essential oil is 2.980%.

[0056] Step 2, Preparation of microcapsules containing camphor essential oil:

[0057] Add an appropriate amount of β-cyclodextrin to distilled water at 65 °C ± 5 °C and stir until the β-cyclodextrin is completely dissolved to obtain a saturated β-cyclodextrin solution with a mass fraction of approximately 5%.

[0058] Weigh 0.5 g of camphor essential oil and dissolve it with absolute ethanol. Among them, the mass ratio of camphor essential oil to absolute ethanol is 1:20 to obtain a camphor essential oil ethanol solution.

[0059] Slowly add the camphor essential oil ethanol solution to the saturated β-cyclodextrin solution, set the temperature of the magnetic stirrer to 50 °C, the stirring rate to 1000 r / min, stir and embed for 3 h. After the solution cools, place it in a refrigerator at 4 °C for 24 h, then vacuum filter the refrigerated solution, collect the microcapsule solids, wash and collect them with distilled water and absolute ethanol multiple times, and freeze-dry the collected solids to obtain white powdery camphor essential oil microcapsules.

[0060] Step 3, Preparation of camphor essential oil microcapsule antibacterial fresh-keeping paper:

[0061] Mix polyethylene glycol 600 and polyethylene glycol 8000 in a mass ratio of 1:2, heat and dissolve to obtain a polyethylene glycol solution. Add camphor essential oil microcapsule powder to the polyethylene glycol solution. After the camphor essential oil microcapsule powder is completely dissolved, obtain a camphor essential oil microcapsule coating solution. Among them, the mass fraction of camphor essential oil microcapsule powder in the camphor essential oil microcapsule coating solution is 1%.

[0062] Use a pipette to suck an appropriate amount of the camphor essential oil microcapsule coating solution, and use a glass rod to evenly coat the camphor essential oil microcapsule coating solution on the filter paper. After natural drying, prepare the camphor essential oil microcapsule antibacterial fresh-keeping paper.

[0063] Example 2

[0064] A preparation method of camphor essential oil microcapsule antibacterial fresh-keeping paper, the difference from Example 1 is that in Step 3, the mass fraction of camphor essential oil microcapsule powder in the camphor essential oil microcapsule coating solution is 2%. The specific preparation method includes the following steps:

[0065] Step 1, Prepare camphor essential oil according to the method in Step 1 of Example 1.

[0066] Step 2: Prepare powdery camphor essential oil microcapsules according to the method in Step 2 of Example 1.

[0067] Step 3: Preparation of camphor essential oil microcapsule antibacterial preservative paper:

[0068] Mix polyethylene glycol 600 and polyethylene glycol 8000 in a mass ratio of 1:2, heat and dissolve them to obtain a polyethylene glycol solution. Add camphor essential oil microcapsule powder to the polyethylene glycol solution. After the camphor essential oil microcapsule powder is completely dissolved, a camphor essential oil microcapsule coating solution is obtained. Among them, the mass fraction of the camphor essential oil microcapsule powder in the camphor essential oil microcapsule coating solution is 2%.

[0069] Use a pipette to suck an appropriate amount of the camphor essential oil microcapsule coating solution, and use a glass rod to evenly coat the camphor essential oil microcapsule coating solution on the filter paper. After natural drying, the camphor essential oil microcapsule antibacterial preservative paper is prepared.

[0070] Example 3

[0071] A preparation method of camphor essential oil microcapsule antibacterial preservative paper, which is different from Example 1 in that in Step 3, the mass fraction of the camphor essential oil microcapsule powder in the camphor essential oil microcapsule coating solution is 3%. The specific preparation method includes the following steps:

[0072] Step 1: Prepare camphor essential oil according to the method in Step 1 of Example 1.

[0073] Step 2: Prepare powdery camphor essential oil microcapsules according to the method in Step 2 of Example 1.

[0074] Step 3: Preparation of camphor essential oil microcapsule antibacterial preservative paper:

[0075] Mix polyethylene glycol 600 and polyethylene glycol 8000 in a mass ratio of 1:2, heat and dissolve them to obtain a polyethylene glycol solution. Add camphor essential oil microcapsule powder to the polyethylene glycol solution. After the camphor essential oil microcapsule powder is completely dissolved, a camphor essential oil microcapsule coating solution is obtained. Among them, the mass fraction of the camphor essential oil microcapsule powder in the camphor essential oil microcapsule coating solution is 3%.

[0076] Use a pipette to suck an appropriate amount of the camphor essential oil microcapsule coating solution, and use a glass rod to evenly coat the camphor essential oil microcapsule coating solution on the filter paper. After natural drying, the camphor essential oil microcapsule antibacterial preservative paper is prepared.

[0077] Comparative Example 1

[0078] A preparation method of preservative paper includes the following steps:

[0079] After mixing polyethylene glycol 600 and polyethylene glycol 8000 in a mass ratio of 1:2, heat and dissolve them to obtain a polyethylene glycol solution. Use a pipette to suck an appropriate amount of the polyethylene glycol solution, and use a glass rod to evenly coat the polyethylene glycol solution on the filter paper. After natural drying, a fresh-keeping paper is prepared.

[0080] Table 1 Feeding conditions of different camphor essential oil microcapsules

[0081] Example Content of camphor essential oil microcapsules Grouping Example 1 1％ <![CDATA[P 1％ <!-- 5 -->]]> Example 2 2％ <![CDATA[P 2％ > Example 3 3％ <![CDATA[P 3％ > Comparative Example 1 0 <![CDATA[P0]]>

[0082] Test 1: Analysis of the antibacterial performance of camphor essential oil.

[0083] The formula of PDA solid medium: 200 g of peeled potatoes, 20 g of agar and glucose respectively, and distilled water is made up to 1000. The specific preparation method is as follows:

[0084] Cut 200 g of peeled potatoes into small pieces and put them into a pot, add distilled water to 1000 so that the potato pieces are completely immersed in the distilled water. Heat to boiling on a heater and keep it for 20 min - 30 min. Filter through four layers of gauze while it is hot in a measuring cup, discard the filter residue, and make up the filtrate to 1000 with distilled water.

[0085] Put 1000 mL of the filtrate into a pot, add 20 g of glucose and 20 g of agar, then place it on an asbestos net and heat it with a small fire, and continuously stir with a glass rod to prevent the agar from sticking to the bottom or overflowing. After the agar is completely dissolved, make up the distilled water to 1000, then sterilize it at 121 °C under high pressure for 20 min. Take it out and shake it well, and let it cool naturally to room temperature to obtain PDA solid medium, which is stored in a 4 °C refrigerator for later use.

[0086] The formula of PDB liquid medium: 200 g of peeled potatoes, 20 g of glucose, and distilled water is made up to 1000.

[0087] Activation of the strain: Select the kiwifruit spoilage bacterium - Penicillium sp., and after picking the Penicillium sp. strain stored at 4 °C with an inoculation loop, re-inoculate it onto the PDA medium and culture it in a constant temperature incubator at 28 °C for 48 h to obtain the activated strain.

[0088] Preparation of the bacterial suspension: Carry out PDB liquid culture on the activated strain, culture it at 28 °C and 160 r / min in a constant temperature shaker for 48 h. Use the plate counting method to prepare a gradient dilution of the bacterial suspension with PDB liquid medium, and adjust the concentration of the bacterial suspension to 1×10 6 CFU.

[0089] Determination of the antibacterial zone: The filter paper method was used to measure the diameter of the antibacterial zone. The specific method is as follows: Filter papers with a diameter of 6 mm were immersed in the camphor essential oil prepared in Example 1 for 1 h to 2 h for standby. 100 μL of the bacterial suspension was added to the prepared PDA plate and spread evenly with a spreading rod, and then left to stand for 5 min. Then, the filter papers soaked with camphor essential oil were placed at the center of the culture medium inoculated with Penicillium, and the experiment was repeated three times as the experimental group. Filter papers soaked with distilled water were placed at the center of the culture medium inoculated with Penicillium as the control group. Then, both the experimental group and the control group were placed in a constant temperature incubator at 28 °C for 48 h. After the culture, the diameter of the antibacterial zone was measured to analyze the antibacterial property of the camphor essential oil against Penicillium. The results are as Figure 1 shown.

[0090] As Figure 1 the results show, the camphor essential oil prepared in Example 1 of the present invention has an obvious inhibitory effect on Penicillium.

[0091] Test 2: Thermal stability analysis of camphor essential oil and essential oil microcapsules.

[0092] A thermogravimetric analyzer was used to determine the thermal stability of camphor essential oil and camphor essential oil microcapsules. The specific method is as follows:

[0093] Taking the camphor essential oil and camphor essential oil microcapsules prepared in Example 1 as samples, the temperature was raised from 30 °C to 800 °C at a rate of 10 °C / min under a N2 atmosphere, and the mass change of the samples during this process was observed. The results are as Figure 2 shown.

[0094] As Figure 2 the results show, the thermal stability of camphor essential oil and camphor essential oil microcapsules was studied by thermogravimetric analysis at 30 °C to 800 °C. Among them, in the temperature range of 30 °C to 230 °C, the mass loss of camphor essential oil was relatively large. When the temperature reached 230 °C, the mass retention rate of camphor essential oil was only 8.2%, but then this mass loss gradually slowed down. When the temperature reached 360 °C, the mass retention rate of camphor essential oil was 1.65%.

[0095] There was no obvious mass loss of the camphor essential oil microcapsules during the temperature rise from 30 °C to 200 °C. The weight loss trend began to increase from 200 °C to 300 °C. In the temperature range of 300 °C to 400 °C, the mass of the camphor essential oil microcapsules decreased rapidly, and the weight loss phenomenon was particularly obvious. The mass retention rate decreased from 84.57% to 10.39%, indicating that the camphor essential oil microcapsules had good thermal stability within 300 °C. When the temperature exceeded 300 °C, β-cyclodextrin was thermally decomposed, the microcapsule wall material was damaged, and the core material camphor essential oil volatilized rapidly, resulting in an accelerated weight loss of the microcapsules. Thus, it can be seen that the microcapsules on the surface of the camphor essential oil microcapsules can effectively protect the camphor essential oil, reduce the volatilization loss of the camphor essential oil, and have good thermal stability.

[0096] Test 3: Analysis of the sustained-release performance of camphor essential oil microcapsules.

[0097] The specific method is as follows:

[0098] Weigh 10 g of the camphor essential oil microcapsules prepared in Example 1, store them at a constant temperature of 25 °C, measure the oil content of the camphor essential oil microcapsules every 2 days, and calculate the relative cumulative release rate at different storage times. The results are as Figure 3 shown. The sustained-release performance of the camphor essential oil microcapsules is reflected by the relative cumulative release rate. The calculation formula for the relative cumulative release rate of the camphor essential oil microcapsules is as follows:

[0099]

[0100] Among them, CR represents the relative cumulative release rate of the camphor essential oil microcapsules, %; M t represents the oil content of the camphor essential oil microcapsules on the t-th day, %; M0 represents the oil content of the camphor essential oil microcapsules on the 0-th day, %.

[0101] From Figure 3 the results, it can be seen that at room temperature, the release of the camphor essential oil microcapsules shows: rapid release in the initial stage, and then tends to be gentle. At the beginning, the release rate of the camphor essential oil microcapsules is relatively fast, probably because the newly prepared camphor essential oil microcapsules have a relatively high oil content and the surface contains unencapsulated essential oil, resulting in a relatively high essential oil release rate; then it tends to be gentle, mainly due to the function of the microcapsules on the surface of the camphor essential oil microcapsules. The film formed by β-cyclodextrin coats the camphor essential oil, and the core material diffuses outward through the pores on the capsule wall, effectively reducing the volatilization of the camphor essential oil components and prolonging the release time of the camphor essential oil. The test results show that the camphor essential oil microcapsules prepared in Example 1 are stable in nature after being placed at room temperature for 20 days, have good sustained-release performance, and can be effectively applied to food preservation.

[0102] Test 4: Verification of the fresh-keeping effect of camphor essential oil microcapsule antibacterial fresh-keeping paper on kiwifruit.

[0103] Test materials: The kiwifruit used is Shaanxi Cuixiang kiwifruit, purchased from the local farmers' market. PET flip-top container, 50 cm × 25 cm × 5 cm. The full English name of PET is Polyethylene Terephthalate, and the Chinese name is polyethylene terephthalate.

[0104] Fresh-keeping method: The single fresh-picked kiwifruit fruits are washed with clear water and then dried naturally for standby. The dried kiwifruit fruits are randomly divided into five groups:

[0105] Treatment group 1: Wrap the single kiwifruit fruits with the camphor essential oil microcapsule antibacterial fresh-keeping paper prepared in Example 1, denoted as P 1％ .

[0106] Treatment group 2: The single kiwifruit was wrapped with the camphor essential oil microcapsule antibacterial fresh-keeping paper prepared in Example 2, denoted as P 2％ .

[0107] Treatment group 3: The single kiwifruit was wrapped with the camphor essential oil microcapsule antibacterial fresh-keeping paper prepared in Example 2, denoted as P 3％ .

[0108] Treatment group 4: The single kiwifruit was wrapped with the fresh-keeping paper prepared in Comparative Example 1, denoted as P0.

[0109] Control group: The single kiwifruit without any treatment was used as the control group, denoted as CK.

[0110] The kiwifruits in different treatment groups were wrapped with the camphor essential oil microcapsule antibacterial fresh-keeping paper obtained in the examples, placed in PET flip-top containers respectively, stored at room temperature, and then the physical and chemical indexes and sensory characteristics were tested.

[0111] Measurement method:

[0112] Observation of the appearance change of kiwifruit: Three kiwifruits were placed in each group. Under the same environmental conditions, the appearance of the kiwifruits in each group was photographed at regular intervals to observe the appearance change and decay of the kiwifruits.

[0113] Measurement of the surface color of kiwifruit: The color change of the kiwifruit was measured by a precision colorimeter, and the change of the L* value was observed. Each group was measured 3 times repeatedly. The L* value is a chromaticity value, indicating the lightness of the color, that is, the brightness of the color. Its value range is usually 0-100; among them, L* = 0 indicates complete black with no light reflection; L* = 100 indicates complete white with perfect reflection; L* = 50 indicates neutral gray.

[0114] Measurement of the weight loss rate: The weight method was used for measurement. The weights of the kiwifruits in the 5 groups before and after treatment were measured respectively, and the weight loss rate was calculated according to the following formula:

[0115] Weight loss rate = (initial fresh weight - fresh weight after storage) / fresh weight after storage × 100%.

[0116] Measurement of hardness: A GY-3 type hardness tester was used. Three points were selected at the equatorial part of the kiwifruit, and the skin with a thickness of 1 cm 2 was peeled off for measurement. The hardness tester was indicated to 10 nm for reading, and the average value of the three measurement results was taken.

[0117] Determination of soluble solid content: It was determined using a hand-held refractometer. The kiwifruit was ground into a homogenized paste, and the supernatant was taken after filtration. 300 μL of the liquid was pipetted onto the hand-held refractometer, evenly distributed without bubbles, and then measured. Each treatment was repeated 3 times. The soluble solid content was denoted as SSC.

[0118] Determination of titratable acid content: The acid-base titration method was used, and the end of the titration was judged according to the color change of phenolphthalein. The titratable acid content was denoted as TA.

[0119] Determination of vitamin C content: The content of vitamin C in kiwifruit was calculated according to the determination of total ascorbic acid in fruits and vegetables in GB12392 - 90.

[0120] Determination of malondialdehyde content: It was determined using the thiobarbituric acid method. Malondialdehyde was denoted as MDA.

[0121] During the storage period, the appearance changes, chromaticity, weight loss rate, hardness, soluble solid content, titratable acid content, vitamin C content, and malondialdehyde content of kiwifruit were detected as quality indicators, and the results are as Figures 4 to 11 shown.

[0122] It can be Figure 4 seen that with the extension of the storage time, the pericarp of kiwifruit showed a phenomenon of deepening color and decreasing brightness under different treatments. At 10 d, the kiwifruit in the control group began to shrink, and with the passage of time, the shrinkage became severe and spoilage occurred. Compared with the control group, the ripening, shrinkage, and rotting times of other treatment groups were postponed. For the P0 group, the preservative paper effectively slowed down the reduction of water in kiwifruit, thus making the dehydration and shrinkage slower. The P1%, P2%, and P3% groups all showed good preservation effects, and with the increase in concentration, the preservation time was correspondingly extended, slowing down the shrinkage of kiwifruit fruits and inhibiting the lesions and mildew caused by microorganisms. Especially, the P3% group extended the storage period of kiwifruit from 16 d to 40 d, effectively extending the shelf life of kiwifruit.

[0123] It can be Figure 5 seen that with the extension of the storage time, the L* values of all groups of fruits decreased. The L* of the fruits in the treatment groups with added microcapsules was always greater than that of the control group. At 16 d, the L* value of the control group was 38.37, while the treatment groups with added microcapsules remained above 44%. Until the 42nd day, the L* value of P3% was still 40.17%. This indicates that the antibacterial preservative paper of camphor essential oil microcapsules can delay the change of the epidermal color of kiwifruit fruits, slow down the browning rate, keep it with good appearance quality and sensory characteristics, and thus has a high commerciality.

[0124] It can be Figure 6It can be seen that the weight loss rate of each group increases with the prolongation of storage time. Among them, the control group has the fastest rising rate, the P3% group rises more slowly and has the lowest weight loss rate. The weight loss rate of the control group reaches 15.6% on the last day of storage, while the P 1％ 、P 2％ 、P 3％ are only 7.64%, 7.55% and 6.08% respectively. Compared with the control group, the weight loss rate is 51.02%, 51.60% and 61.03% lower, indicating that all treatment groups have reduced the weight loss rate of the fruit. And with the increase of the microcapsule addition amount, the weight loss rate of kiwifruit slows down significantly. When the microcapsule addition amount is 3%, the effect is the best.

[0125] It can be seen from Figure 7 that the hardness of kiwifruit generally shows a downward trend with the increase of storage time. In the initial stage of storage, the reduction rate is relatively fast; during the ripening and decay process of kiwifruit, the hardness value cannot be detected. Even in the P3% group, it only lasts until 22 days. It can be seen from the figure that the hardness of the CK group and the P0 group both decrease rapidly. Adding camphor essential oil microcapsules can effectively weaken the decrease of kiwifruit hardness. Among them, the P3% group performs the best and remains in a relatively stable state all the time, indicating that the antibacterial fresh-keeping paper with camphor essential oil microcapsules can maintain the fresh period of kiwifruit and extend its shelf life.

[0126] It can be seen from Figure 8 that during the whole storage period of kiwifruit, the change of soluble solids in its fruit first increases and then decreases. The increase of soluble solids represents that the fruit tends to the mature stage, while when the soluble solids decrease, it means that the fruit has reached maturity, and then the consumption of respiration is relatively large, resulting in a decrease in the content of soluble solids. The content of soluble solids in the CK group is the highest at 12 days, the P0 group reaches the maximum at the 18th day, P1% and P2% reach the maximum at the 22nd day, and P3% reaches the maximum at the 22nd day, and then shows a rapid decline. This shows that the treatment groups all have a certain inhibitory effect on the increase of soluble solids, slow down the ripening of kiwifruit, and can also reduce the consumption by fruit respiration, so that the fruit nutrients remain at a relatively high level, which is beneficial to the preservation of kiwifruit.

[0127] It can be seen from Figure 9It can be seen that with the increase of storage time, the titratable acid content of both the control group and the treatment group decreased, but the content of the treatment group always exceeded that of the control group. After 6 days of storage, the titratable acid contents of CK and P0 were 1.51% and 1.83% respectively, while those of the P1%, P2%, and P3% groups were not much different, all about 1.9%, indicating that the decreasing rate of the titratable acid content in the treatment group was less than that in the control group. After 16 days of storage, the titratable acid content of the CK group was 1.16%, a decrease of 44.76% compared with the beginning, while that of the P3% treatment group was 1.74%, a decrease of 23.35%. In the later stage of storage, the decrease rate of the titratable acid value in the P3% group was slow, indicating that the antibacterial and fresh-keeping paper with camphor essential oil microcapsules could better slow down the degradation rate of titratable acid during the storage of kiwifruit and retain the fruit flavor to the greatest extent.

[0128] As Figure 10 is known, the vitamin C content generally decreased with the extension of time and decreased relatively fast. After 16 days, the vitamin C content in the CK group decreased from 56.93 mg / 100 g at the beginning to 17.75 mg / 100 g, and the loss rate of vitamin C content was as high as 68.82%. The vitamin C content in the P0 group decreased by 53.43%, while those in the P1%, P2%, and P3% groups only decreased by 42.42%, 41.14%, and 38.61% respectively, indicating that although paper-based packaging could reduce the loss of vitamin C content in kiwifruit, adding essential oil microcapsules was more effective. This might be because the microcapsules could delay the oxidation of vitamin C in kiwifruit and affect the activity of enzymes related to vitamin C metabolism, thereby effectively reducing the loss of vitamin C content and maintaining the nutrients in kiwifruit fruits.

[0129] As Figure 11 is known, with the extension of storage time, the malondialdehyde content in kiwifruit showed an increasing trend. The growth rate of the CK group was relatively fast, increasing to 2% in 6 days, while the growth of the P0 group and the microcapsule-added groups was relatively slow. The P3% group only increased by 3.07%, and the upward trend of the treatment group was slower with a smaller increase amplitude. The malondialdehyde content in the CK group reached 3.94% on the 16th day, and those in the P1% and P2% groups were 2.60% and 2.15% respectively, much less than that in the CK group. The P3% group was only 1.94% on the 16th day, less than half of the content in the CK group, and did not reach 4.41% until the 40th day of storage. This indicates that the antibacterial and fresh-keeping paper with camphor essential oil microcapsules has a significant effect on weakening the increase of malondialdehyde content. This might be because the camphor essential oil microcapsules inhibited the growth of spoilage bacteria in kiwifruit, maintained the integrity of the fruit cell membrane, weakened the lipid peroxidation reaction, and inhibited the oxidative deterioration of kiwifruit, thereby better extending the shelf life of kiwifruit.

[0130] Based on the above analysis, it can be known that by adjusting the addition amount of camphor essential oil microcapsules in the embodiments of the present invention, the shelf life of fruits such as kiwifruit can be significantly extended and the fresh-keeping effect can be improved. Specifically, it is manifested as follows:

[0131] Prolong the shelf life and maintain the appearance quality: The antibacterial and fresh-keeping paper containing 1% - 3% of camphor essential oil microcapsules can significantly delay the change of peel color and the browning rate, and maintain good appearance quality. Especially for group P 3％ The storage period of kiwifruit was extended from 16 days to 40 days in group P

[0132] Reduce the weight loss rate: The antibacterial and fresh-keeping paper containing 1% - 3% of camphor essential oil microcapsules can effectively slow down the water loss and maintain the freshness of the fruit.

[0133] Maintain nutritional components: The antibacterial and fresh-keeping paper containing 1% - 3% of camphor essential oil microcapsules can delay the decline of soluble solid content, titratable acid content and vitamin C content. Especially for group P 3％ The loss of vitamin C and the degradation of titratable acid were significantly slowed down in group P, and the nutritional value and flavor of the fruit were maintained.

[0134] Inhibit oxidative deterioration: The antibacterial and fresh-keeping paper containing 1% - 3% of camphor essential oil microcapsules can significantly inhibit the formation of malondialdehyde, inhibit lipid peroxidation reaction, maintain the integrity of cell membrane, and delay the oxidative deterioration of the fruit.

[0135] Example 4

[0136] A preparation method of antibacterial and fresh-keeping paper containing camphor essential oil microcapsules is prepared according to the method of Example 3, except that the mass ratio of polyethylene glycol 600 to polyethylene glycol 8000 is 1:1.

[0137] The specific preparation method includes the following steps:

[0138] Step 1: Prepare camphor essential oil according to the method of Step 1 in Example 1.

[0139] Step 2: Prepare powdery camphor essential oil microcapsules according to the method of Step 2 in Example 1.

[0140] Step 3: Preparation of antibacterial and fresh-keeping paper containing camphor essential oil microcapsules:

[0141] Mix polyethylene glycol 600 and polyethylene glycol 8000 according to the mass ratio of 1:1, heat and dissolve to obtain a polyethylene glycol solution. Add camphor essential oil microcapsule powder to the polyethylene glycol solution, and after the camphor essential oil microcapsule powder is completely dissolved, obtain a camphor essential oil microcapsule coating solution. Among them, the mass fraction of camphor essential oil microcapsule powder in the camphor essential oil microcapsule coating solution is 3%.

[0142] Use a pipette to aspirate an appropriate amount of the camphor essential oil microcapsule coating solution, and use a glass rod to evenly coat the camphor essential oil microcapsule coating solution on the filter paper. After natural drying, a camphor essential oil microcapsule antibacterial and fresh-keeping paper is prepared.

[0143] Example 5

[0144] A preparation method of a camphor essential oil microcapsule antibacterial and fresh-keeping paper is prepared according to the method of Example 3, the difference is that the mass ratio of polyethylene glycol 600 to polyethylene glycol 8000 is 1:1.5.

[0145] The specific preparation method includes the following steps:

[0146] Step 1, prepare camphor essential oil according to the method in Step 1 of Example 1.

[0147] Step 2, prepare powdery camphor essential oil microcapsules according to the method in Step 2 of Example 1.

[0148] Step 3, preparation of camphor essential oil microcapsule antibacterial and fresh-keeping paper:

[0149] Mix polyethylene glycol 600 and polyethylene glycol 8000 in a mass ratio of 1:1.5, heat and dissolve to obtain a polyethylene glycol solution. Add camphor essential oil microcapsule powder to the polyethylene glycol solution. After the camphor essential oil microcapsule powder is completely dissolved, a camphor essential oil microcapsule coating solution is obtained. Among them, the mass fraction of the camphor essential oil microcapsule powder in the camphor essential oil microcapsule coating solution is 3%.

[0150] Use a pipette to aspirate an appropriate amount of the camphor essential oil microcapsule coating solution, and use a glass rod to evenly coat the camphor essential oil microcapsule coating solution on the filter paper. After natural drying, a camphor essential oil microcapsule antibacterial and fresh-keeping paper is prepared.

[0151] Table 2 Feeding situation of different mass ratios of polyethylene glycol 600 and polyethylene glycol 8000

[0152]

[0153]

[0154] Test 5: Coating uniformity test of different groups

[0155] Observe the distribution of camphor essential oil microcapsules on the surface of the camphor essential oil microcapsule antibacterial and fresh-keeping paper prepared in Examples 3 to 5 through an optical microscope.

[0156] In Example 4, when the mass ratio of polyethylene glycol 600 to polyethylene glycol 8000 was 1:1, it was found that the microcapsules on the surface of the prepared camphor essential oil microcapsule antibacterial and fresh-keeping paper were unevenly distributed, with dense and sparse areas, indicating that the coating uniformity was affected to a certain extent. Similar situations also existed in other examples, but the degree was slightly lighter than that in Example 4.

[0157] In Example 3, when the mass ratio of polyethylene glycol 600 to polyethylene glycol 8000 was 1:2, the microcapsules on the surface of the prepared camphor essential oil microcapsule antibacterial and fresh-keeping paper were relatively evenly distributed.

[0158] This shows that when the mass ratio of polyethylene glycol 600 to polyethylene glycol 8000 is 1:2, the microcapsules on the surface of the prepared camphor essential oil microcapsule antibacterial and fresh-keeping paper can be relatively evenly distributed to improve the fresh-keeping effect.

[0159] Test 6: Physical property test of different groups of papers.

[0160] Test the tensile strength and flexibility of the camphor essential oil microcapsule antibacterial and fresh-keeping paper prepared in Examples 3 to 5.

[0161] Through experimental analysis, it can be seen that the tensile strength of the camphor essential oil microcapsule antibacterial and fresh-keeping paper prepared in Example 4 is slightly lower than that of the paper in Example 3, and the flexibility is slightly better. The tensile strength of the camphor essential oil microcapsule antibacterial and fresh-keeping paper prepared in Example 5 is higher than that of the paper in Example 3, but the flexibility is poor, and it is more likely to have creases in the folding test.

[0162] This shows that under the condition that the mass ratio of polyethylene glycol 600 to polyethylene glycol 8000 is 1:2, polyethylene glycol 600 and polyethylene glycol 8000 exhibit excellent performance in terms of viscosity and surface tension.

[0163] Test 7: Antibacterial property test of different groups.

[0164] Using the colony counting method, antibacterial tests were carried out on the camphor essential oil microcapsule antibacterial and fresh-keeping paper prepared in Examples 3 to 5, with common spoilage bacteria such as Escherichia coli and Staphylococcus aureus as the test objects.

[0165] Through the analysis of the antibacterial test results, it can be seen that the antibacterial rate of the camphor essential oil microcapsule antibacterial and fresh-keeping paper prepared in Example 4 against Escherichia coli is 80%, and the antibacterial rate against Staphylococcus aureus is 75%. The antibacterial rate of the camphor essential oil microcapsule antibacterial and fresh-keeping paper prepared in Example 5 against Escherichia coli is 85%, and the antibacterial rate against Staphylococcus aureus is 80%; the antibacterial rate of the camphor essential oil microcapsule antibacterial and fresh-keeping paper prepared in Example 3 against Escherichia coli is 90%, and the antibacterial rate against Staphylococcus aureus is 88%.

[0166] The results of the antibacterial performance test showed that under the condition that the mass ratio of polyethylene glycol 600 to polyethylene glycol 8000 was 1:2, the prepared camphor essential oil microcapsule antibacterial fresh-keeping paper demonstrated excellent performance in terms of viscosity, surface tension, and interaction with camphor essential oil microcapsules, thereby being able to improve the antibacterial performance against spoilage bacteria such as Escherichia coli and Staphylococcus aureus.

[0167] Test 8: Fresh-keeping performance test of different groups.

[0168] Select a perishable food, such as cherry tomatoes, and package them with the camphor essential oil microcapsule antibacterial fresh-keeping paper prepared in Examples 3 to 5. Under the same storage conditions, such as the same temperature, humidity, etc., observe the shelf life of the cherry tomatoes. The temperature is 5°C to 10°C, and the humidity is 85%.

[0169] The cherry tomatoes packaged in Example 4 began to show obvious signs of decay after 3 days. The cherry tomatoes packaged in Example 5 began to show signs of decay after 4 days; the cherry tomatoes packaged in Example 3 began to show slight signs of decay after 5 days.

[0170] From the above verification tests, it can be seen that when the mass ratio of polyethylene glycol 600 to polyethylene glycol 8000 is 1:2, during the preparation of the camphor essential oil microcapsule antibacterial fresh-keeping paper, good comprehensive performance is shown in aspects such as coating uniformity, fresh-keeping performance, antibacterial performance, and paper physical properties. Deviating from this ratio will lead to a decline in some properties. Therefore, the mass ratio of polyethylene glycol 600 to polyethylene glycol 8000 is preferably 1:2.

[0171] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A preparation method of a camphor essential oil microcapsule antibacterial and fresh-keeping paper, characterized in that, It includes the following steps: Mix the camphor essential oil microcapsules evenly with the polyethylene glycol solution to obtain a camphor essential oil microcapsule coating solution; coat the camphor essential oil microcapsule coating solution on the surface of the paper-based material, and after drying, obtain the camphor essential oil microcapsule antibacterial and fresh-keeping paper. The polyethylene glycol solution is prepared by mixing polyethylene glycol 600 and polyethylene glycol 8000 in a mass ratio of 1:

2.

2. The preparation method of the camphor essential oil microcapsule antibacterial and fresh-keeping paper according to claim 1, characterized in that, The mass fraction of the camphor essential oil microcapsules in the camphor essential oil microcapsule coating solution is 1% - 3%.

3. The preparation method of the camphor essential oil microcapsule antibacterial fresh-keeping paper according to claim 1, characterized in that, The camphor essential oil microcapsules are prepared with β-cyclodextrin as the wall material and camphor essential oil as the core material.

4. The preparation method of the camphor essential oil microcapsule antibacterial and fresh-keeping paper according to claim 3, characterized in that, The camphor essential oil microcapsules are prepared by the following method: Dissolve the camphor essential oil in an ethanol solvent to obtain a camphor essential oil ethanol solution. Dissolve β-cyclodextrin in water to obtain a saturated β-cyclodextrin solution. Drop the camphor essential oil ethanol solution into the saturated β-cyclodextrin solution, carry out stirring and embedding, then carry out static treatment at 0°C - 4°C, filter, collect the solid matter, and freeze-dry to obtain the camphor essential oil microcapsules.

5. The preparation method of the camphor essential oil microcapsule antibacterial and fresh-keeping paper according to claim 4, characterized in that, The mass ratio of the camphor essential oil to the ethanol solvent is 1:15 - 20.

6. The preparation method of the camphor essential oil microcapsule antibacterial and fresh-keeping paper according to claim 4, wherein, The mass ratio of the camphor essential oil ethanol solution to the saturated β-cyclodextrin solution is 1:6 - 9.

7. The preparation method of the camphor essential oil microcapsule antibacterial and fresh-keeping paper according to claim 4, characterized in that, The paper-based material is filter paper.

8. An antibacterial and fresh-keeping paper with camphor essential oil microcapsules, characterized in that, It is prepared by using the preparation method of the camphor essential oil microcapsule antibacterial and fresh-keeping paper described in any one of claims 1 - 7.

9. Application of camphor essential oil microcapsule antibacterial fresh-keeping paper as a fresh-keeping material for fruits and vegetables, characterized in that, The camphor essential oil microcapsule antibacterial and fresh-keeping paper is the camphor essential oil microcapsule antibacterial and fresh-keeping paper described in claim 8.

10. Use of the camphor essential oil microcapsule antibacterial fresh-keeping paper according to claim 9 as a fresh-keeping material for fruits and vegetables, characterized in that, The camphor essential oil microcapsule antibacterial and fresh-keeping paper is mainly used for inhibiting Penicillium or spoilage bacteria as a fresh-keeping material for fruits and vegetables.

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