Fruit ripening method based on combination of plasma sterilization and interaction of internal and external source ethylene

Abstract

The invention discloses a fruit ripening method based on synergistic interaction of plasma sterilization and internal and external source ethylene, which comprises the following steps: firstly, efficiently purifying and sterilizing the environment of a ripening warehouse body through a pulse plasma technology to prevent rotting microorganisms from influencing the ripening process and fruit quality; then, 65% Vol high-alcohol rice wine is adopted for nanometer atomization treatment, and release of endogenous ethylene in the fruits is stimulated in an oriented mode; meanwhile, a composite ethylene slow-release supplement is adopted to replace a traditional ethephon solution, the supplement comprises an ethephon (CHClOP) / beta-cyclodextrin inclusion compound, Tween 80 and sodium bicarbonate, and stable slow release of exogenous ethylene is achieved. According to the method, the comprehensive effects of sterilization, uniform color changing, sugar accumulation and loss reduction in the ripening process are synchronously achieved through plasma space purification and internal and external source ethylene cooperative regulation and control, leap-type optimization of fruit quality parameters is achieved, no harmful by-product is generated, and the dual strict requirements of industrial processing for ripening efficiency and product quality are met.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of postharvest processing of fruits, in particular to a fruit ripening method based on synergistic interaction of plasma sterilization and endogenous and exogenous ethylene, especially suitable for large-scale and standardized ripening processing of tropical respiration-climacteric fruits such as mangoes. BACKGROUND

[0002] Fruit ripening is a process of accelerating fruit ripening through artificial intervention, which is widely used in large-scale fruit processing industry. In production, in order to reduce storage and transportation losses, fruits are usually harvested at 60-70% maturity, and then ripening treatment is carried out to achieve uniform maturity, so as to ensure the consistency of color and flavor of dried fruit, fruit juice, whole fruit processing and other products, and realize standardized production. At present, the ripening technology mainly relies on ethylene, ethanol and other ripening media, or combines physical and chemical means for auxiliary regulation and control, but there are still many technical bottlenecks, and it is difficult to balance the ripening efficiency and fruit quality:

[0003] 1. Lack of prevention and control of microbial contamination in library space

[0004] Microorganisms (such as Botrytis cinerea) are the key factors leading to quality deterioration during the ripening process of tropical fruits. They can cause fruit rot and mold through air circulation and contact transmission, significantly reducing the ripening yield. Traditional techniques mainly focus on sterilization treatment of the fruit surface, such as ultrasonic cleaning, chemical agent soaking, etc., but lack of systematic sterilization program for the space and environment of the ripening library, which cannot block the cross-contamination risk of microorganisms from the source, resulting in high fruit rot loss rate during the ripening process.

[0005] 2. Limited improvement of fruit quality, difficult to match natural ripening standards

[0006] Existing ripening techniques mainly rely on single exogenous ethylene (such as ethephon solution) or simple physical environmental regulation, which can accelerate fruit softening and color change, but cannot coordinate the regulation of fruit internal metabolism. The specific performance is that the synthesis of aroma substances is insufficient, the sugar-acid ratio is unbalanced, and the pectin degradation is uneven, which ultimately leads to the lack of flavor and soft texture of the fruit after ripening, and there is a significant gap in quality compared with naturally ripened fruits, which is difficult to meet the quality requirements of high-end processing products.

[0007] 3. Poor ripening uniformity, hindering standardized processing

[0008] In traditional ripening methods, uneven distribution of ethylene gas and low effective ingredient penetration rate lead to significant differences in ripening degree of fruits in the same batch. This inconsistency in ripening degree makes it difficult for raw materials to meet the requirements of continuous processing production lines, seriously affecting production efficiency and product standardization level, and becomes a key factor restricting the large-scale development of the industry.

[0009] 4. Low utilization rate of traditional ethephon preparations, insufficient synergistic effect

[0010] The surface tension of traditional ethephon aqueous solution is as high as 72.8 mN / m, and after nano-atomization, droplets with a contact angle greater than 90° are easily formed on the wax layer of fruits, which makes it difficult for the active ingredients to penetrate, most of the drug is lost, and the utilization rate is low. At the same time, the release rate of ethylene from ethephon aqueous solution is fast, and the action time is short, which cannot form synergy with the ripening rhythm of the fruit itself, and it is difficult to realize the synchronous optimization of quality parameters such as flavor, texture, color, etc.

[0011] 5. Limitations of existing synergistic technology

[0012] Although related technologies have tried to combine plasma or cyclodextrin complexes to optimize the ripening process, the former mostly uses plasma-activated solution to treat fruits, without sterilizing the library space; the latter mostly uses cyclodextrin to stabilize ethylene inhibitors, without realizing the slow release of ethephon and the synergistic regulation of endogenous and exogenous ethylene. Therefore, there is an urgent need in the art to develop an integrated ripening technology that can simultaneously solve the problems of space sterilization, quality improvement, ripening uniformity and drug utilization rate, breaking through the limitations of traditional technology "trade-offs". Through retrieval, the existing related patents have the following limitations:

[0013] Chinese patent CN 119605849A "Mango precise ripening method based on ethylene gas" discloses a method of ripening fruits and vegetables with plasma-activated water, but it only deals with the surface of the fruit and does not involve sterilizing the ripening library space, which cannot block cross-contamination of microorganisms;

[0014] Chinese patent CN 119184108B "Fruit and vegetable flower preservation bag" proposes a preservation technology of cyclodextrin inclusion of ethylene inhibitors, without involving the slow release modification of ethephon and the synergistic regulation of endogenous and exogenous ethylene;

[0015] Foreign patent US9877832B2 uses ethephon and surfactant to compound ripening agent, but does not solve the problems of too fast ethylene release rate and uneven ripening, and has no sterilization synergy design;

[0016] The existing technologies do not realize the integrated regulation of "space sterilization-endogenous stimulation-exogenous slow release-environment synergy", which makes it difficult to balance the efficiency and quality of ripening.

[0017] The present invention aims to overcome the above-mentioned defects by integrating pulsed plasma space sterilization, rice wine endogenous ethylene stimulation, β-cyclodextrin inclusion slow release of exogenous ethylene, and precise control of multiple environmental parameters, forming a synergistic technology system and breaking through the bottleneck of traditional technology. SUMMARY

[0018] The present invention aims to provide a fruit ripening method based on the interaction of endogenous and exogenous ethylene, which breaks through the limitations of traditional ripening technology in terms of efficiency and quality, and provides a better solution for postharvest processing of fruits and vegetables.

[0019] To solve the above technical problems, the application adopts the following technical solutions:

[0020] The application provides a fruit ripening method, comprising the following steps:

[0021] (1) Environmental sterilization: using plasma space purification technology to sterilize the environment of the ripening warehouse;

[0022] (2) Endogenous ethylene stimulation: spraying rice wine with a concentration of 65% Vol on the fruit to be ripened through a nano atomization device;

[0023] (3) Exogenous ethylene supplement: within 30 to 90 minutes after step (1) is completed, spraying a composite ethylene slow-release supplement through the nano atomization device;

[0024] (4) Environmental control: controlling the ripening environment to meet the set gas concentration and temperature and humidity conditions.

[0025] Preferably, in step (1), the plasma space purification technology is pulse plasma space purification technology, and the sterilization target is to make the total number of bacterial colonies in the space air <100 CFU / m³.

[0026] More preferably, the pulse plasma space purification device works through an air circulation system. After dust is filtered by a primary and medium efficiency filter, air is ionized by a high-voltage pulse discharge assembly to generate high-energy particles, ultraviolet rays, and active oxygen particles such as ozone and hydrogen peroxide, and the air is instantaneously and effectively disinfected with a disinfection efficiency of not less than 90% for one pass. This technology can be operated under the condition of personnel on duty, realizing efficient and safe in-situ continuous sterilization.

[0027] Preferably, in step (2), the spraying amount of rice wine is 0.01%-0.03% of the weight of the fruit, more preferably 0.02%; and the droplet size generated by the nano atomization device is 50-200 nm, more preferably 100-150 nm.

[0028] The ethanol contained in the 65% Vol rice wine can effectively stimulate the biosynthesis pathway of endogenous ethylene of the fruit, and the trace flavor substances such as esters and aldehydes naturally contained therein can synergize with the fruit metabolism to assist in improving the permeability of exogenous substances in the cuticle layer of the fruit.

[0029] Preferably, in step (3), the spraying amount of the composite ethylene slow-release supplement is 0.003%-0.005% of the weight of the fruit, more preferably 0.004%.

[0030] The composite ethylene slow-release supplement is composed of the following components in percentage by weight: ethylene / β-cyclodextrin inclusion compound 15%-25%, Tween 80 1.5%-3%, sodium bicarbonate 0.5%-1%, nano-zinc oxide 0.01%-0.03%, and the balance is deionized water.

[0031] The content Y of the ethylene / β-cyclodextrin inclusion compound and the content X of the Tween 80 satisfy the relationship: 1.8 ≤ Y / X ≤ 12.5. When the value of Y / X is lower than the lower limit, the relative excess of the surfactant is easy to form micelles, resulting in uneven dispersion of the inclusion compound; when the value of Y / X is higher than the upper limit, the inclusion compound is overloaded and flocculation is easy to occur, which will affect the stability and penetration efficiency of the supplement.

[0032] The sodium bicarbonate is used to maintain the pH of the system in the weak alkaline range (about 8.0-8.5), effectively inhibiting the acidic decomposition of ethylene to generate harmful by-products such as dichloroethane. The nano-zinc oxide has a particle size of 20-50 nm, which can realize the dual antibacterial protection of "space + fruit surface" in cooperation with plasmon.

[0033] Preferably, in step (4), the ripening environmental conditions are: ethylene concentration 400-800 ppm, carbon dioxide concentration 10000-20000 ppm, oxygen concentration 2%-5%, temperature 36-38℃, and relative humidity 77%-83%. By precisely controlling this "low oxygen, high carbon dioxide, suitable temperature and humidity, and ethylene concentration" environment, the respiration intensity, ethylene action and post-ripening physiological process of the fruit are highly synchronized.

[0034] The application provides a composite ethylene slow-release supplement for the above-mentioned method, which is composed of the following components in percentage by weight: ethylene / β-cyclodextrin inclusion compound 15%-25%, Tween 80 1.5%-3%, sodium bicarbonate 0.5%-1%, nano-zinc oxide 0.01%-0.03%, and the balance is deionized water; and the content Y of the ethylene / β-cyclodextrin inclusion compound and the content X of the Tween 80 satisfy the relationship: 1.8 ≤ Y / X ≤ 12.5.

[0035] The application provides a preparation method of an ethylene / β-cyclodextrin inclusion compound, which is a key slow-release component in the above-mentioned supplement, and has the following steps.

[0036] a. Dissolve β-cyclodextrin in deionized water at 60℃ to prepare a solution with a mass concentration of 15%;

[0037] b. Add ethylene in a molar ratio of 1:3 of ethylene to β-cyclodextrin, and stir at 1000-1200 rpm for 2 hours;

[0038] c. The reaction solution is refrigerated at 4 DEG C for 12 hours, and the precipitated solid is collected and filtered through a 0.22-micron filter to obtain the filter residue;

[0039] d. The filter residue is vacuum freeze-dried at -40 DEG C and 10 Pa for 24 hours to obtain a white powder of the inclusion compound.

[0040] The method significantly reduces the industrial production cost compared to the centrifugal method while ensuring a high inclusion rate (>90%) through a specific "filter residue" process.

[0041] The application provides an application of the method of the first aspect in ripening of a climacteric fruit.

[0042] Preferably, the climacteric fruit includes but is not limited to mango, passion fruit, and jackfruit.

[0043] The application provides an application of the method of the first aspect in pre-treatment of a fruit before processing, to provide raw materials with uniform maturity and stable quality for subsequent processing.

[0044] Preferably, the application includes standardization of ripening pre-treatment of raw fruit before preparation of instant fresh fruit, preserved fruit, fruit juice, fruit wine, and the like.

[0045] In summary, due to the adoption of the technical solutions described above, the application at least includes the following beneficial effects:

[0046] The application realizes a significant technical breakthrough in the field of fruit ripening through the innovative combination of endogenous and exogenous ethylene synergistic regulation and precise environmental control, and mainly embodies the following four aspects of beneficial effects:

[0047] (1) The application generates low-temperature plasma with rich active particles through fast pulse discharge, and achieves rapid disinfection and inactivation of various bacteria, viruses, and fungi in aerosol form (as shown in FIG. 1). Figure 1 Compared with traditional sterilization methods such as sterilization of processing environment by using hydrogen peroxide, ozone, ultraviolet lamp, and high-voltage electrostatic adsorption, or disinfection and sterilization of raw materials and processing tools by using NaClO and the like, the pulse plasma space purification technology of the application can generate physical and chemical sterilization factors (high-energy electrons, ions, and free radicals) with multiple sterilization capabilities under the excitation of pulse high voltage, which can significantly reduce the air bacterial count in the factory building without affecting the health of the operating workers, can ensure normal production activities of the operating workers during the sterilization process, and has the advantages of high efficiency and low energy consumption.

[0048] (2) The present application significantly optimizes the flavor, texture and color of fruits by stimulating the release of endogenous ethylene with 65% Vol rice wine and combining exogenous regulation of the complex ethylene slow-release supplement. Compared with traditional ripening methods, the content of characteristic aroma in fruits is greatly increased, the sugar-acid ratio is significantly improved, and the degradation of pectin and softening of fruit pulp are more balanced, making the ripened fruits not only uniform in maturity, but also better in taste and richer in flavor. At the same time, the color transformation is obvious, and the peel color is closer to the natural ripening state, meeting the sensory needs of the high-end market. The present application uses rice wine brewed from grains instead of directly using alcohol as an endogenous ethylene release activator, which is natural and residue-free, and can more effectively promote the formation and transformation of internal characteristic aroma in fruits.

[0049] (3) Traditional ripening techniques often result in uneven fruit maturity due to uneven ethylene action and too fast release rate, making it difficult to meet the requirements of large-scale production. The present application improves the penetration efficiency of ethylene in the cuticle layer of fruit by nanospray technology, and innovatively introduces a β-cyclodextrin inclusion slow-release system to achieve stable and continuous release of ethylene, coordinating its action rhythm with the internal ripening physiological process of fruits. This slow-release system, combined with alkaline environment regulation, not only significantly inhibits the generation of harmful by-products, but also fundamentally avoids problems such as uneven softening of fruit pulp and insufficient accumulation of flavor substances caused by too high instantaneous concentration of ethylene. On this basis, precise control of environmental parameters such as O2 concentration, temperature and humidity is supplemented, and the system achieves high synchronization of fruit respiration intensity, ethylene release and texture transformation, ultimately stabilizing batch ripening consistency at over 90%, effectively solving the problem of processing quality fluctuations caused by differences in raw material maturity.

[0050] (4) The present application efficiently completes ripening, significantly shortening the time required by traditional processes and adapting to the rhythm of industrialized continuous production. At the same time, this method shows stable ripening effect on various fruits such as mangoes, passion fruits and jackfruits, significantly optimizing key indicators such as aroma, sugar-acid ratio and color, proving its good universality and repeatability, and can be widely applied in the processing field of instant dried fruits, fruit juice, etc., providing reliable technical support for standardized production.

[0051] In summary, the present application develops a comprehensive microbial control technology of "processing environment space pulse plasma sterilization to prevent microbial infection / fruit ripening nanometer C2H6O to inhibit microorganisms / ", combined with the endogenous and exogenous ethylene interaction awakening technology of "nanometer atomization C2H6O, C2H6ClO3P / control library body environment and gas composition", scientifically regulates the synergistic interaction of ethylene metabolism pathway and environmental factors, and surpasses the existing technology in efficiency, quality and safety. It breaks through the limitations of traditional ripening techniques in low efficiency, poor quality and high rot rate, and is suitable for standardized processing of various fruits such as mangoes, providing a better solution for postharvest processing of fruits and vegetables. BRIEF DESCRIPTION OF DRAWINGS

[0052] Figure 1 Figure 1 is a schematic diagram of a pulse plasma space disinfection system for a fruit ripening warehouse according to an embodiment of the present application. In the figure, 1 is a fruit ripening warehouse; and 2 is a plasma generator.

[0053] Figure 2 Figure 4 is a photograph showing the appearance of mango fruits under different ripening treatments, in which A is single ethylene ripening, B is plasma treatment alone, and C is the ripening technology according to the present application.

[0054] Figure 3 Figure 5 is a graph showing the ripening rate of fruits under different ripening technologies over time. DETAILED DESCRIPTION

[0055] The following examples can help those skilled in the art to have a more comprehensive understanding of the present application, but can not limit the present application in any way.

[0056] Example 1: Preparation of ethylene / β-cyclodextrin inclusion complex

[0057] This example proposes a method for preparing an ethylene / β-cyclodextrin inclusion complex, the steps of which are as follows:

[0058] 1) Dissolve 150 g of β-cyclodextrin in 60°C deionized water to form a 15 wt% solution;

[0059] 2) Add 83 g of 40% ethylene solution (molar ratio 1:3), and stir at 1200 rpm for 2 h to obtain a reaction solution;

[0060] 3) After the reaction solution is refrigerated at 4°C for 12 h, collect the solid precipitate, filter it through a 0.22 μm PVDF filter membrane (discard the filtrate), and take the filter residue;

[0061] 4) Freeze-dry the filter residue at -40°C and 10 Pa for 24 h to obtain the ethylene / β-cyclodextrin inclusion complex.

[0062] Compare the method of this example with other methods, including the filter residue method and the centrifugation method (centrifuge the reaction solution at 10000 rpm for 15 min (4°C), discard the supernatant, and collect the precipitate) to test the inclusion rate (the percentage of ethylene successfully encapsulated by β-cyclodextrin in the total amount added, HPLC method), free ethylene residue, and slow-release half-life (the time required for the release amount of ethylene in the inclusion complex to reach 50% of the initial concentration, reflecting the sustained release capacity of ethylene).

[0063] The results are shown in Table 1.

[0064] Table 1

[0065]

[0066] The filtering residue taking method can ensure high inclusion rate, and the operation cost is reduced by 63% (the equipment can be simplified as a common suction filter device) compared with the centrifugal method. The centrifugal method can achieve high inclusion rate, but is significantly inferior to the filtering method in product purity and industrialization cost. Compared with the centrifugal method, the method can maintain high inclusion rate (92.4%) while avoiding high energy consumption and high cost of high-speed centrifugal equipment, and is more suitable for industrialized production.

[0067] Example 2: Optimization of the component of the composite ethylene slow-release supplement

[0068] This example proposes a composite ethylene slow-release supplement, and the performance of the supplement is tested and compared with other components, and the groups are as follows:

[0069] Group A (the application): inclusion compound 20% + Tween 80 2.0% + NaHCO3 0.8% + nano-ZnO 0.02% (30 nm);

[0070] Group B (without NaHCO3): omit NaHCO3;

[0071] Group C (without nano-ZnO): omit nano-ZnO;

[0072] Group D (Y / X = 1.5, above the lower limit): inclusion compound 15% + Tween 80 3.0%;

[0073] Group E (Y / X = 13, above the upper limit): inclusion compound 26% + Tween 80 2.0%;

[0074] Group F: traditional ethephon solution.

[0075] The performances of the supplements of the above groups are compared, and the results are shown in Table 2:

[0076] Table 2: Performance test of the supplements of each group

[0077]

[0078] The supplement obtained by the combination of the application has the best effect, wherein the sodium bicarbonate can block the nucleophilic substitution reaction of the HCl by-product and ethephon in an alkaline environment at a pH value temperature, thereby inhibiting the generation of dichloroethane, and the nano-zinc oxide (ZnO) destroys the mycelial cell membrane by releasing Zn²⁺. In addition, the parameter interval of Y / X (Tween / inclusion compound) needs to be strictly controlled in the ideal interval defined in the application. If the inclusion compound is insufficient, the micelles of Tween 80 are formed, and if the inclusion compound is overloaded, flocculation occurs. When Y / X < 1.8 (such as group D), the surfactant Tween 80 is relatively excessive, micelles are easily formed, the inclusion compound is not uniformly dispersed, and the permeability is greatly reduced; when Y / X > 12.5 (such as group E), the inclusion compound is easily flocculated when overloaded, which also affects its uniform dispersion and permeability.

[0079] Example 3: Mango ripening process

[0080] As shown in Figure 1 , the pulse plasma space purification system used in the present application mainly includes a fruit ripening warehouse 1 and a plasma generator 2 integrated in it. The plasma generator 2 is usually arranged in the air circulation duct of the warehouse body, which contains a customized high-voltage discharge module capable of ionizing air under pulse action to produce various active substances including high-energy electrons, ultraviolet photons, ozone and hydroxyl radicals for instant disinfection of the airflow passing through.

[0081] This embodiment proposes a mango ripening process, including the following processing flow:

[0082] (1) Start the plasma generator integrated in the air circulation system of the ripening warehouse (as shown in Figure 1 ), continuously sterilize the warehouse environment until the total number of space bacterial colonies is <100 CFU / m³;

[0083] (2) Spray 60% ethanol (0.02% fruit weight) on 7-8 mature mangoes;

[0084] (3) Spray the supplement described in Example 2 (0.004% fruit weight, droplet size 150 nm) after 60 minutes;

[0085] (4) Control the environment: ethylene 600 ppm, CO2 15000 ppm, O2 3%, temperature 37°C, humidity 80% RH.

[0086] Compare the operation of this embodiment with the single ethephon ripening technology and the plasma alone processing technology of mango pulp various data indicators, including:

[0087] Total number of space bacterial colonies, ripening consistency, rot rate, weight loss rate, ethylene permeability, ripening period

[0088] Characteristic aroma components: HS-SPME / GC-MS detects characteristic aroma (sum of 12 key compounds such as terpenes and esters);

[0089] Texture parameters: TA.XT Plus texture analyzer (probe P / 5, down pressure speed 2 mm / s);

[0090] Color index: HunterLab colorimeter (D65 light source, 10° observation angle).

[0091] The test results are shown in Table 3:

[0092] Table 3 Comparison of mango ripening efficiency and overall quality of each ripening treatment group

[0093]

[0094] As Figure 2 shown, the appearance of mangoes treated by the three ripening techniques is obviously different. The ripening degree of mangoes treated by single ethylene is inconsistent, and more black spot fruits (surface black spot > 2 mm) appear. The black spot phenomenon can be effectively improved by single plasma treatment, but there are still a few fruits with black spots. The mangoes treated by the present application have uniform and bright yellow peel color without black spots. Figure 3 The change of the ripening degree of fruits treated by the present application and the prior art with ripening time is shown. It can be obviously seen that the ripening cycle required by the present application is short, and the fruits are concentrated in the ripening stage and have high consistency. As shown in Table 3, the present application has the effect of reducing loss and increasing efficiency. The total number of space colonies, fruit rot rate and weight loss rate of mangoes treated by the present application are significantly reduced. The ethylene permeability is significantly increased. The ripening consistency of fruits is obviously improved. The ripening cycle is obviously shortened. The present application combines the following technologies to improve the ripening efficiency and overall quality:

[0095] The synergistic design of pulse plasma sterilization and nano atomization ripening: The environment of the sterilized library provides a clean basis for ethylene action, avoids the interference of microbial metabolites with ethylene signal transduction, and improves the consistency of ripening response;

[0096] The synergistic mechanism of rice wine and ethylene / β-cyclodextrin inclusion compound: 65% Vol rice wine not only stimulates endogenous ethylene, but also promotes the permeation of exogenous ethylene in the fruit wax layer, forming a double permeation strengthening effect with Tween 80;

[0097] The complex function of sodium bicarbonate and nano zinc oxide: Sodium bicarbonate adjusts the pH of the system to 8.0-8.5, inhibits the decomposition of ethylene to produce harmful byproducts such as dichloroethane, and nano zinc oxide cooperates with plasma to achieve dual antibacterial effect of "space + fruit surface", and the moldy rate is reduced to below 0.3%.

[0098] Table 4 Comparison of sensory quality of mangoes in each ripening treatment group

[0099]

[0100] As shown in Table 4, compared with the fresh fruit benchmark before ripening, the total content of characteristic aroma of the present application group is significantly increased by 26.1% within 48h, the sugar-acid ratio is greatly optimized by 67.8%, and the pectin degradation and hardness decrease are more than 30%, the a * value changes from negative to positive, and the b *The value is significantly improved, and the fruit has no bitter and numb taste. In comparison, the total amount of characteristic aroma and the sugar-acid ratio of the single ethylene-ripening group and the plasma-only treatment group change significantly less than the application group in the same period, which proves that the technical solution of the application can simultaneously and accelerate the optimization of fruit flavor, sweetness, texture and color, breaking through the limitations of slow effect and limited quality improvement of traditional ripening technology. On the other hand, the pectin degradation rate and hardness reduction rate of the application group are lower than those of the single ethylene-ripening group and the plasma-only treatment group, which effectively controls the fruit texture during the ripening process and effectively avoids the problem of excessively soft and rotten fruit pulp that is not conducive to solid-state processing. The above results confirm that the application can effectively improve the appearance quality and flavor quality of the fruit.

[0101] Example 4: Industrial application

[0102] Scenario: Apply the method of Example 3 to the standardization pretreatment of instant mango preserved raw materials;

[0103] Production line parameters:

[0104] Treatment capacity: 5 tons / batch;

[0105] Environmental control accuracy: ±0.5℃, ±2%RH;

[0106] Supplement consumption: 0.2 kg / ton of raw materials.

[0107] Ten batches were tested in succession, as shown in Table 5:

[0108] Table 5 Important indicators of 10 batches in succession

[0109]

[0110] The above index tests verify the feasibility of the method of the application in industrial application.

[0111] In addition, the applicant further increases the test of other fruits, specifically tests the indicators of aroma, sugar-acid ratio, pectin, and a value, compares the indicators of the ripened fruit with those of the untreated fruit, calculates the percentage (improvement / drop percentage = [(treatment group value - untreated group value) ÷ untreated group value] × 100%), to verify the universality of the method;

[0112] Test variety: mango (Taikang), passion fruit, and jackfruit. The test results are shown in Table 6:

[0113] Table 6 Test results of different fruits

[0114]

[0115] The mango, passion fruit, jackfruit and other various test varieties have significant improvement effect on key quality indicators such as aroma, sugar-acid ratio, and can effectively promote pectin degradation and color conversion (a value is converted from negative to positive). This shows that the ripening method based on the interaction of endogenous and exogenous ethylene provided by the present application has good universality and can provide reliable technical support for the pretreatment of standardized raw materials for various original flavor product processing.

[0116] Example 5: Repetitive verification test

[0117] Using the mango ripening process of Example 3, 30 batches of industrial production (60 tons / batch) were continuously carried out, and the key indicators are as follows in Table 7:

[0118] Table 7

[0119]

[0120] The results in Table 7 show that the method of the present application has excellent repeatability and stability under industrial scale, and the fluctuation range of each indicator is ≤2.5%, meeting the requirements of standardized production.

[0121] Although the present application has been described in detail in the foregoing description with general principles and specific embodiments, some modifications or improvements can be made on the basis of the present application, which is obvious to those skilled in the art. Therefore, these modifications or improvements made on the basis of not deviating from the spirit of the present application, all belong to the scope of protection required by the present application.

Claims

1. A method for ripening fruit based on the synergistic interaction of plasma sterilization and endogenous and exogenous ethylene, characterized in that, Includes the following steps: (1) Sterilization of ripening storage: The storage environment is sterilized by pulsed plasma space purification technology until the total number of airborne bacteria is <100 CFU / m³. (2) Endogenous ethylene activation: Using a nano-atomizing device with a droplet size of 50-200nm, spray 65% ​​Vol rice wine onto the fruit to be ripened, with the spraying amount being 0.01-0.03% of the fruit weight; (3) External ethylene regulation: After completing step (1), spray the compound ethylene slow-release supplement through a nano-atomizing device at intervals of 30-90 min. The amount of the spray is 0.003-0.005% of the fruit weight. The compound ethylene slow-release supplement contains the following components by weight percentage: 15-25% ethephon / β-cyclodextrin inclusion complex, 1.5-3% Tween 80, 0.5-1% sodium bicarbonate, 0.01-0.03% nano zinc oxide, and the remainder is deionized water. The content Y of the ethephon / β-cyclodextrin inclusion complex and the content X of the Tween 80 satisfy the following relationship: 1.8 ≤ Y / X ≤ 12.

5. (4) Control of ripening environment: The ripening environment should meet the following conditions: ethylene concentration in the warehouse is 400-800 ppm, CO2 concentration is 10000-20000 ppm, O2 concentration is 2-5%, temperature is 36-38℃, and humidity is 77-83%.

2. The method according to claim 1, characterized in that, In step (1), the plasma space purification technology is pulsed plasma space purification technology, which uses high-energy particles, ultraviolet rays and active oxygen particles generated by discharge after the air is drawn in and filtered. The purification efficiency is not less than 90% in one pass.

3. The method according to claim 1, characterized in that, In step (2), the amount of 65% Vol rice wine sprayed is 0.02% of the fruit weight, and in step (3), the amount of compound ethylene slow-release supplement sprayed is 0.004% of the fruit weight.

4. The method according to claim 1, characterized in that, The ethephon / β-cyclodextrin inclusion complex was prepared by the following steps: a. Dissolve β-cyclodextrin in deionized water at 60℃ to prepare a solution with a mass concentration of 15%; b. Add ethephon to the solution from step a at a molar ratio of ethephon to β-cyclodextrin of 1:3, and stir at 1000-1200 rpm for 2 hours; c. Refrigerate the reaction solution obtained in step b at 4°C for 12 hours, collect the precipitated solid, filter it through a 0.22 μm filter membrane and take the filter residue; d. The filter residue was freeze-dried under vacuum at -40°C and 10 Pa for 24 hours to obtain the ethephon / β-cyclodextrin inclusion complex.

5. The method according to claim 1, characterized in that, In step (2), the droplet size of the nano-atomization is 100-150 nm.

6. A compound ethylene slow-release supplement, characterized in that, It is composed of the following components by weight percentage: 15%-25% ethephon / β-cyclodextrin inclusion complex, 1.5%-3% Tween 80, 0.5%-1% sodium bicarbonate, 0.01%-0.03% nano zinc oxide, and the balance being deionized water; wherein the content Y of the ethephon / β-cyclodextrin inclusion complex and the content X of the Tween 80 satisfy the following relationship: 1.8 ≤ Y / X ≤ 12.

5.

7. The application of the method according to any one of claims 1-6 in the large-scale ripening of climacteric fruits, characterized in that, The climacteric fruits mentioned include mango, passion fruit, and jackfruit.

8. The application of the method according to any one of claims 1-5 in the pre-treatment of raw fruit for ripening before processing ready-to-eat fruit products or processed fruit products.

9. The application according to claim 8, characterized in that, The ready-to-eat fruit products or processed fruit products include fresh fruit, dried fruit, fruit juice or fruit wine.

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