Low-temperature plasma cold sterilization method suitable for postharvest preservation of agaricus bisporus
By using a medium-barrier low-temperature plasma (DBD-CPⅠ) device to treat button mushrooms with low-temperature plasma, the problem of poor preservation effect caused by parameter uncertainty in existing technologies is solved. This achieves effective sterilization and preservation of nutrients, thus extending the shelf life of button mushrooms.
Patent Information
- Application Number
- CN202511661552.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-13
- Publication Date
- 2026-01-06
AI Technical Summary
The lack of effective low-temperature plasma treatment parameters in existing technologies makes it difficult to predict the post-harvest preservation effect of button mushrooms, and traditional methods have problems such as complicated operation, low efficiency, and chemical residues.
The low-temperature plasma DBD-CPⅠ equipment was used to treat button mushrooms with low-temperature plasma. The specific parameters were: treatment temperature 25℃, voltage 50-155kV, time 1-16min, and frequency 70-195Hz. The mushrooms were then sealed in polyethylene plastic bags for treatment.
It effectively sterilizes, delays the softening and browning of button mushrooms, maintains stable nutritional components, and extends shelf life.
Smart Images
Figure CN121264516A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of food cold sterilization technology, specifically relating to a low-temperature plasma cold sterilization method suitable for post-harvest preservation of button mushrooms. Background Technology
[0002] Button mushrooms (Agaricus bisporus), commonly known as white mushrooms, are edible macrofungi that have gained global attention for their unique sensory and nutritional value. Post-harvest, button mushrooms have high water content, lack a protective cuticle, exhibit vigorous respiration and transpiration, and are susceptible to microbial infection. This makes them prone to browning, softening, moisture loss, nutrient loss, and microbial contamination after natural harvesting. Therefore, preventing browning and softening of button mushrooms during storage and extending their shelf life have always been challenging problems that researchers have been working to solve.
[0003] In recent years, researchers have explored various preservation methods to address these challenges, including improved packaging techniques, chemical treatments, and irradiation-based biocontrol. However, these methods, while preserving button mushrooms, still have certain limitations, such as complex operation, low efficiency, difficulty in large-scale production, unknown chemical residues, and expensive equipment, which restrict the shelf life of button mushrooms.
[0004] Low-temperature plasma is a relatively new physical cold sterilization technology in food preservation. Low-temperature plasma mainly utilizes active molecules formed by high-voltage ionization. These active molecules possess excellent broad-spectrum bactericidal properties and have been proven to effectively reduce microorganisms in food matrices. However, current technology lacks research on low-temperature plasma preservation technology for button mushrooms. Determining the appropriate low-temperature plasma treatment parameters for button mushrooms is difficult, especially regarding the treatment voltage, frequency, and time, presenting certain technical barriers. Inappropriate discharge parameters and treatment time can severely affect the quality of button mushrooms, leading to unpredictable preservation results. Summary of the Invention
[0005] To address the shortcomings of existing technologies, the present invention aims to provide a low-temperature plasma cold sterilization method suitable for post-harvest preservation of button mushrooms, thus solving the problems in the existing technologies.
[0006] The objective of this invention can be achieved through the following technical solutions:
[0007] A low-temperature plasma sterilization method suitable for post-harvest preservation of button mushrooms includes: packing button mushrooms into a polypropylene box and sealing it for low-temperature plasma treatment.
[0008] The low-temperature plasma treatment has a processing temperature of 25℃, a processing voltage of 50-155kV, a processing time of 1-16min, and a processing frequency of 70-195Hz.
[0009] Furthermore, the sealed packaging uses polyethylene plastic bags.
[0010] Furthermore, the equipment used to perform cryogenic plasma treatment is: a dielectric barrier cryogenic plasma DBD-CPⅠ equipment.
[0011] Furthermore, the distance between the electrode plates of the device is 60cm.
[0012] Furthermore, the low-temperature plasma treatment is performed at least once.
[0013] Furthermore, the processing frequency is 130Hz.
[0014] Furthermore, the processing voltage is 95kV.
[0015] Furthermore, the processing time is 10 minutes.
[0016] Furthermore, the processing voltage is 140kV.
[0017] Furthermore, the processing frequency is 145Hz.
[0018] The beneficial effects of this invention are:
[0019] Compared with traditional packaging and preservation methods, the low-temperature plasma preservation method for button mushrooms provided by this invention utilizes a non-contact cold sterilization method with low-temperature plasma. Firstly, it can effectively sterilize the mushrooms. Secondly, it delays the softening and browning of button mushrooms after harvest. In addition, it can maintain the stability of the nutritional components of button mushrooms, reduce the metabolic loss of nutrients in button mushrooms after harvest, and effectively extend the shelf life of button mushrooms. Attached Figure Description
[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0021] Figure 1 This is a graph showing the effect of different treatment frequencies on the whiteness and sterilization rate of Agaricus bisporus.
[0022] Figure 2 This is a graph showing the effect of different processing voltages on the whiteness and sterilization rate of Agaricus bisporus.
[0023] Figure 3 This is a graph showing the effect of different processing times on the whiteness and sterilization rate of button mushrooms according to the present invention;
[0024] Figure 4This is a comparison chart of the appearance changes of different groups of button mushrooms during storage according to the present invention.
[0025] Figure 5 This is a graph showing the changes in L* of different groups of Agaricus bisporus during storage according to the present invention;
[0026] Figure 6 This is a graph showing the changes in browning degree of different groups of Agaricus bisporus during the storage period of this invention;
[0027] Figure 7 This is a graph showing the changes in polyphenol oxidase activity in different groups of Agaricus bisporus during storage.
[0028] Figure 8 This is a graph showing the changes in peroxidase activity in different groups of Agaricus bisporus during storage.
[0029] Figure 9 This is a graph showing the changes in hardness of different groups of button mushrooms during storage during the present invention.
[0030] Figure 10 This is a graph showing the changes in the total number of Agaricus bisporus colonies in different groups during the storage period of this invention;
[0031] Figure 11 This is a graph showing the changes in soluble solids content of different groups of Agaricus bisporus during the storage period of this invention;
[0032] Figure 12 This is a graph showing the changes in vitamin C content of different groups of button mushrooms during storage during the present invention.
[0033] Figure 13 This is a graph showing the changes in total protein content of different groups of button mushrooms during storage. Detailed Implementation
[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0035] A low-temperature plasma cold sterilization method suitable for post-harvest preservation of button mushrooms includes:
[0036] The button mushrooms were placed in polypropylene boxes and sealed for low-temperature plasma treatment; the parameters for the low-temperature plasma treatment are as follows:
[0037] The processing temperature is 25℃, the number of processing times is 1, the distance between the plates is 60cm, the processing voltage is 50-155kV, the processing time is 1-16min, and the processing frequency is 70-195Hz.
[0038] The specific measurement method used in the embodiments of the present invention is as follows:
[0039] 1. Determination of total bacterial count in Agaricus bisporus.
[0040] This invention refers to the method in GB4789.2-2016 "Determination of Total Microbial Colony Count in Food" to determine the number of microorganisms in button mushrooms.
[0041] 2. Determination of whiteness and browning degree of Agaricus bisporus
[0042] This invention uses a 3NH colorimeter (3NH SR-66; Shenzhen 3NH Technology Co., Ltd., Shenzhen, China) to record the color as L. * a * and b * The formula for determining the Brownness Index (BI) is as follows:
[0043]
[0044] BI = [100 × (X 0.31)]
[0045] 3. Determination of polyphenol oxidase and peroxidase activities
[0046] Extraction of crude enzyme solution: Add 5g of Agaricus bisporus to 5mL of extraction buffer containing 1mmol / L IPEG, 4% PVPP and 1% Triton X-100. After complete grinding, centrifuge at 12000g for 30min at 4℃.
[0047] Peroxidase activity determination: First, 0.5 mL of crude enzyme solution was mixed with 3.0 mL of 25 mmol / L guaiacol solution, followed by the addition of 200 μL of 0.5 mol / L hydrogen peroxide and rapid shaking. The absorbance of the reaction mixture was then measured six times at 470 nm. One unit (U) of POD activity was defined as a change of 0.01 per minute at 470 nm. POD activity is expressed as U g. -1 Fresh weight indicates.
[0048] Assay for polyphenol oxidase activity: First, mix 4.0 mL of 50 mmol / L sodium acetate buffer and 1.0 mL of 50 mmol / L catechol, then add 100 μL of crude enzyme extract and mix thoroughly. The absorbance of the reaction mixture was measured six times at 420 nm, with 1-minute intervals. One unit of PPO activity (U) was defined as a change of 0.01 per minute at 420 nm. PPO activity is expressed as U g. -1 Fresh weight indicates.
[0049] 4. Determination of the firmness of button mushrooms
[0050] This invention uses a fruit hardness tester to determine the hardness of button mushrooms, with the tester needle being 8mm.
[0051] 5. Determination of soluble solids content in Agaricus bisporus
[0052] First, weigh 10g of button mushroom sample and add it to 15mL of deionized water (pH 7). Then, stir the mixture in the mortar and filter it through four layers of gauze to remove the filter residue. Subsequently, use the supernatant to measure the TSS (%) using a refractometer (A1701161, ATAGO, Japan).
[0053] 6. Determination of Vitamin C and Total Protein Content in Agaricus bisporus
[0054] This invention uses a biological reagent kit produced by Nanjing Jiancheng Biotechnology Co., Ltd. to determine the vitamin C and protein content in Agaricus bisporus.
[0055] Example 1
[0056] After harvesting, button mushrooms were transported to a laboratory constant temperature and humidity chamber for pre-cooling for 12 hours as soon as possible. 120±10g of intact, uniformly sized button mushrooms, free from browning, pests, diseases, and mechanical damage, were selected and weighed, and placed into polypropylene boxes, which were then sealed in polyethylene plastic bags. The packaged button mushrooms were placed in the treatment chamber of a medium-barrier low-temperature plasma DBD-CPⅠ device for sterilization. The treatment temperature was 25℃, the treatment was performed once, the distance between the electrodes was 60cm, and the equipment sterilization parameters were set as follows: treatment voltage 125kV, treatment time 7min. Treatment frequencies of 70, 95, 120, 145, 170, and 195Hz were used, with button mushrooms not treated with low-temperature plasma serving as a control group. The total colony count and whiteness of the button mushrooms were measured. Each indicator was measured three times, and the results are as follows: Figure 1 As shown.
[0057] Example 2
[0058] The difference between this embodiment and Embodiment 1 is that the processing frequency is fixed at 145Hz, the processing time is 7 minutes, and the processing voltages are 50, 65, 80, 95, 110, 125, and 155kV, respectively. The results are as follows. Figure 2 As shown.
[0059] Example 3
[0060] The difference between this embodiment and Embodiment 1 is that the processing frequency is fixed at 145Hz, the processing voltage is 125kV, and the processing times are 1, 4, 7, 10, 13, and 16 minutes, respectively. The results are as follows: Figure 3 As shown.
[0061] Example 4
[0062] In this embodiment, after harvesting, the button mushrooms were transported to a laboratory constant temperature and humidity chamber for pre-cooling for 12 hours as soon as possible. 120±10g of intact, uniformly sized button mushrooms, free from browning, pests, diseases, and mechanical damage, were selected and weighed, then placed in polypropylene boxes and sealed in polyethylene plastic bags. The packaged button mushrooms were placed in the treatment chamber of a medium-barrier low-temperature plasma (DBD-CPⅠ) device for sterilization. The treatment temperature was 25℃, the treatment was performed once, and the distance between the electrodes was 60cm. The sterilization parameters were set as follows: treatment frequency 130Hz, treatment voltage 95kV, and treatment time 10min. Button mushrooms that had not undergone low-temperature plasma treatment served as a control group. All groups of button mushrooms were stored at 4℃ and 90% relative humidity for 12 days, and sensory and physiological / biochemical indicators were measured every 3 days.
[0063] Experimental Test
[0064] The button mushrooms treated with low-temperature plasma in Example 4 were used as the experimental group, and the button mushrooms that were not treated with low-temperature plasma were used as the control group. The following experimental tests were conducted.
[0065] After 12 days of storage, the appearance of button mushrooms changes as follows: Figure 4 As shown, yellowish-brown spots appeared on the control group of button mushrooms.
[0066] The changes in whiteness and browning of button mushrooms after 12 days of storage are as follows: Figure 5 , 6 As shown in the figure, the L* color of the control group of button mushrooms was significantly reduced, while the browning degree was significantly increased. This is consistent with the changes in appearance, indicating that low-temperature plasma treatment has a certain inhibitory effect on browning of button mushrooms.
[0067] After 12 days of storage, the changes in polyphenol oxidase in the experimental and control groups of Agaricus bisporus were as follows: Figure 7 As shown, polyphenol oxidase is the main enzyme causing enzymatic browning in fruits and vegetables. Polyphenol oxidase catalyzes the oxidation of endogenous polyphenols in fruits and vegetables into melanin. In this invention, polyphenol oxidase activity increased with prolonged storage, and the enzyme activity in the control group was significantly higher than that in the treatment group. This indicates that the polyphenol oxidase in *Agaricus bisporus* treated with low-temperature plasma was inactivated. Peroxidase is an important redox enzyme that responds to external stimuli in fruits and vegetables. For example... Figure 8 As shown, the peroxidase activity in the experimental group of *Agaricus bisporus* was significantly higher than that in the control group, indicating that the active substances generated by low-temperature plasma activated the expression of peroxidase in *Agaricus bisporus*, resulting in increased enzyme activity in the experimental group.
[0068] Changes in total colony count of Agaricus bisporus in different groups during storage, as shown below Figure 10As shown, with the increase of storage time, the hardness of the control group of button mushrooms decreased, and a significant difference was found between the control group and the treatment group on day 6. This indicates that low-temperature plasma treatment can effectively reduce the softening damage of button mushrooms. In addition, the total number of colonies in the experimental group was significantly lower than that in the control group, indicating that low-temperature plasma treatment can effectively reduce the number of microorganisms on the surface of button mushrooms.
[0069] The changes in soluble solids, vitamin C, and total protein content of different groups of button mushrooms during storage are as follows: Figure 11 , 12 As shown in Figure 13, the soluble solids, vitamin C, and total protein content of the treated mushrooms were significantly higher than those of the control group. This indicates that low-temperature plasma treatment can effectively reduce the physiological metabolism of mushrooms after harvest and maintain the stability of nutrients in the fruiting bodies.
[0070] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0071] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.
Claims
1. A low temperature plasma cold sterilization method suitable for postharvest preservation of Agaricus bisporus, characterized by, Comprising: The Agaricus bisporus is put into a polypropylene box and sealed and packaged, and then subjected to low-temperature plasma treatment. The low-temperature plasma treatment has a treatment temperature of 25 DEG C, a treatment voltage of 50-155 kV, a treatment time of 1-16 min, and a treatment frequency of 70-195 Hz.
2. The low temperature plasma cold sterilization method suitable for postharvest preservation of Agaricus bisporus according to claim 1, characterized in that, The sealed packaging is performed by using a polyethylene plastic bag.
3. The low temperature plasma cold sterilization method suitable for postharvest preservation of Agaricus bisporus according to claim 1, characterized in that, The equipment for performing the low-temperature plasma treatment is a dielectric barrier low-temperature plasma (DBD-CP I) equipment.
4. The low temperature plasma cold sterilization method suitable for postharvest preservation of Agaricus bisporus according to claim 3, characterized in that, The distance between the electrode plates of the equipment is 60 cm.
5. The low temperature plasma cold sterilization method suitable for postharvest preservation of Agaricus bisporus according to claim 1, characterized in that, The low-temperature plasma treatment is performed at least once.
6. The low temperature plasma cold sterilization method suitable for postharvest preservation of Agaricus bisporus according to claim 1, characterized in that, The treatment frequency is 130 Hz.
7. The low temperature plasma cold sterilization method suitable for postharvest preservation of Agaricus bisporus according to claim 1, characterized in that, The treatment voltage is 95 kV.
8. The low temperature plasma cold sterilization method suitable for postharvest preservation of Agaricus bisporus according to claim 1, characterized in that, The treatment time is 10 min.
9. The low temperature plasma cold sterilization method suitable for postharvest preservation of Agaricus bisporus according to claim 1, characterized in that, The treatment voltage is 140 kV.
10. The low temperature plasma cold sterilization method suitable for postharvest preservation of Agaricus bisporus according to claim 1, characterized in that, The treatment frequency is 145 Hz.