Technology for prolonging fresh-keeping time of vegetables and fruits at normal temperature

Abstract

The invention relates to a process for prolonging the fresh-keeping time of vegetables and fruits at normal temperature. The process comprises the following steps: step 1, pretreatment: soaking and washing picked fruits or vegetables with saline water; step 2, preparing an antibacterial membrane solution: preparing a ZIF precursor; then, tannic acid is used for treatment, and ETCH-ZIF powder is obtained; then hesperetin is added for treatment, and Q-ETCH-ZIF powder is obtained; finally, adding a casein solution for treatment to obtain an antibacterial film solution; and 3, coating and packaging. The invention discloses a fresh-keeping process of vegetables and fruits, which comprises the following steps of: cleaning and drying the fruits or the vegetables, treating the fruits or the vegetables with antibacterial film liquid, and sealing the fruits or the vegetables in an air-free fresh-keeping bag, so that the preservation time of the vegetables and the fruits at normal temperature can be prolonged.

Description

Technical Field

[0001] The present invention relates to the field of food preservation, and in particular to a process for prolonging the preservation time of fruits and vegetables at room temperature. Background Art

[0002] Fruits and vegetables are perishable commodities. If fresh fruits and vegetables are to be stored well, in addition to the necessary post-harvest commercial processing, there must also be appropriate storage facilities to reduce the material consumption of fruits and vegetables, delay the ripening and aging process, extend the post-harvest life and shelf life; effectively prevent the growth and reproduction of microorganisms, and avoid the rotting and deterioration of fruits and vegetables due to contamination.

[0003] In the existing fruit and vegetable preservation process, the fruits and vegetables are usually preserved by sulfur fumigation technology, which causes the fruits and vegetables to contain residual sulfur components, causing the fruits and vegetables to have peculiar smells and affecting the health of people who eat such fruits and vegetables. At the same time, the existing preservation methods also make the fruits and vegetables more prone to bacteria growth due to the poor preservation environment, and cause the fruits and vegetables to rot and brown, which is not conducive to the long-term preservation of fruits and vegetables. Summary of the invention

[0004] In view of the problems existing in the prior art, the purpose of the present invention is to provide a process for extending the preservation time of fruits and vegetables at room temperature.

[0005] The purpose of the present invention is achieved by the following technical solutions:

[0006] A process for extending the freshness-keeping time of fruits and vegetables at room temperature, comprising the following steps:

[0007] Step 1, pre-treatment: soak and wash the picked fruits or vegetables with salt water, then rinse with clean water, and then place them in a drying oven for drying to obtain pre-treated fruits and vegetables;

[0008] Step 2, preparing antibacterial film liquid: preparing ZIF precursor; then treating with tannic acid to obtain ETCH-ZIF powder; then adding hesperidin to obtain Q-ETCH-ZIF powder; finally adding casein solution to obtain antibacterial film liquid;

[0009] Step 3, coating and packaging: soak the pre-treated fruits and vegetables in the antibacterial film liquid, or spray the antibacterial film liquid on the surface of the pre-treated fruits and vegetables. After drying, place them in a fresh-keeping bag and seal them to complete the preservation operation.

[0010] Preferably, in the first step, the brine is an aqueous solution of sodium chloride or calcium chloride with a mass concentration of 1%-10%.

[0011] Preferably, in the step 1, the temperature of the drying oven is 25-45°C.

[0012] Preferably, in the second step, the preparation process of the ZIF precursor includes:

[0013] Weigh cobalt nitrate hexahydrate, add it into anhydrous ethanol, and stir to obtain a cobalt nitrate solution; weigh 2-methylimidazole, add it into anhydrous ethanol, and stir to obtain a 2-methylimidazole solution; mix the cobalt nitrate solution and the 2-methylimidazole solution, stir at room temperature for 1-2 hours, let stand for 15-20 hours, and then separate the solid, wash and dry to obtain a ZIF precursor.

[0014] Preferably, in the cobalt nitrate solution of step 2, the mass ratio of cobalt nitrate hexahydrate to anhydrous ethanol is 0.29-0.58:10-20.

[0015] Preferably, in the 2-methylimidazole solution in step 2, the mass ratio of 2-methylimidazole to anhydrous ethanol is 0.11-0.22:10-20.

[0016] Preferably, in the second step, the mass ratio of the cobalt nitrate solution to the 2-methylimidazole solution is 1:2-5.

[0017] Preferably, in the second step, the preparation process of ETCH-ZIF powder comprises:

[0018] Weigh the ZIF precursor and anhydrous ethanol, mix them, then add the tannic acid solution, stir evenly, let it stand for 2-6 hours, then separate the solid, wash and dry it, and then sinter it in a high-temperature furnace, and obtain ETCH-ZIF powder after cooling.

[0019] Preferably, in the step 2, the tannic acid solution is tannic acid and deionized water in a mass ratio of 0.13-0.26:10-20.

[0020] Preferably, in the second step, the mass ratio of the ZIF precursor, the tannic acid solution and the anhydrous ethanol is 1:10-20:15-25.

[0021] Preferably, in the second step, the sintering temperature in the high temperature furnace is 550-650° C., the sintering time is 2-4 hours, and argon is used as the protective gas during the sintering process.

[0022] Preferably, in the second step, the preparation process of Q-ETCH-ZIF powder comprises:

[0023] Hesperidin was added into anhydrous ethanol, and after it was fully dissolved, ETCH-ZIF powder was added, and after being fully mixed, it was stirred in the dark for 3-10 hours. After the treatment, it was dried by nitrogen blowing, and then washed and dried to obtain Q-ETCH-ZIF powder.

[0024] Preferably, in the second step, the mass ratio of ETCH-ZIF powder, hesperetin and anhydrous ethanol is 1:0.8-1.6:20-40.

[0025] Preferably, in the second step, the preparation process of the antibacterial film liquid includes:

[0026] Weigh casein and glycerol and mix them, then gradually pour deionized water into them, stir them thoroughly to obtain a casein solution, then add Q-ETCH-ZIF powder, and after removing bubbles, obtain an antibacterial membrane solution.

[0027] Preferably, in the casein solution in step 2, the casein is α-casein or β-casein, and the mass ratio of casein, glycerol and deionized water is 1:0.25-0.5:35-55.

[0028] Preferably, in the second step, the mass ratio of Q-ETCH-ZIF powder to casein solution is 1:10-20.

[0029] Preferably, in the step 3, the drying is carried out by blowing with nitrogen or drying at 30-40°C.

[0030] Preferably, in the third step, the air in the fresh-keeping bag is replaced with nitrogen or vacuumed before the bag is sealed.

[0031] The beneficial effects of the present invention are:

[0032] 1. The present invention discloses a fruit and vegetable preservation process, which comprises the following steps: washing and drying the fruits or vegetables, treating them with an antibacterial film liquid, and then placing them in an airless fresh-keeping bag and sealing them, thereby extending the storage time of the fruits and vegetables at room temperature.

[0033] 2. The present invention prepares an antibacterial film liquid for the preservation of fruits and vegetables. Different from conventional film liquids, the film liquid of the present invention uses casein and glycerol as film-forming materials, supplemented by the prepared Q-ETCH-ZIF powder as an added modifier. The prepared film layer has good capture and killing capabilities for bacteria, has good antibacterial and fresh-keeping effects, and can greatly extend the shelf life of fruits and vegetables at room temperature. At the same time, the antibacterial film liquid prepared by the present invention is environmentally friendly and non-toxic, and can be quickly removed after washing with water, thereby not affecting the safety of food.

[0034] 3. The Q-ETCH-ZIF powder prepared by the present invention is composed of zinc oxide-doped hollow carbon encapsulated hesperidin. The preparation process uses a metal framework material ZIF precursor as a carrier. The purpose of using tannic acid treatment is to form a hollow structure of the ZIF precursor by etching, thereby enhancing its load capacity and giving the Q-ETCH-ZIF powder a sustained release effect. At the same time, the toxicity of the original metal of the ZIF precursor is eliminated. DETAILED DESCRIPTION

[0035] The technical solution of the present invention is described below through specific examples. It should be understood that the one or more method steps mentioned in the present invention do not exclude the existence of other method steps before and after the combination step or the insertion of other method steps between these explicitly mentioned steps; it should also be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. Moreover, unless otherwise specified, the numbering of each method step is only a convenient tool for identifying each method step, and is not intended to limit the order of arrangement of each method step or to limit the scope of the present invention. The change or adjustment of the relative relationship thereof shall also be regarded as the scope of the present invention without substantially changing the technical content.

[0036] In order to better understand the above technical scheme, the exemplary embodiments of the present invention are described in more detail below. Although exemplary embodiments of the present invention are shown, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present invention and to enable the scope of the present invention to be fully communicated to those skilled in the art.

[0037] The present invention will be further described below in conjunction with the following examples.

[0038] Example 1

[0039] A process for extending the freshness-keeping time of fruits and vegetables at room temperature, comprising the following steps:

[0040] Step 1, pretreatment: soak and wash the picked fruits or vegetables in an aqueous solution of sodium chloride with a mass concentration of 8%, then rinse with clean water, and then dry them in a drying oven at 35°C to obtain pretreated fruits and vegetables;

[0041] Step 2, preparation of antibacterial film solution:

[0042] S1. Weigh cobalt nitrate hexahydrate and add it to anhydrous ethanol, the mass ratio of cobalt nitrate hexahydrate to anhydrous ethanol is 0.43:15, and stir to obtain a cobalt nitrate solution; weigh 2-methylimidazole and add it to anhydrous ethanol, the mass ratio of 2-methylimidazole to anhydrous ethanol is 0.16:15, and stir to obtain a 2-methylimidazole solution; mix the cobalt nitrate solution and the 2-methylimidazole solution, the mass ratio of the cobalt nitrate solution to the 2-methylimidazole solution is 1:3, stir at room temperature for 1 hour, let stand for 18 hours, and then separate the solid, wash and dry to obtain a ZIF precursor;

[0043] S2, tannic acid and deionized water are configured to prepare a tannic acid solution in a mass ratio of 0.19:15, ZIF precursor and anhydrous ethanol are weighed and mixed, and then the tannic acid solution is added, the mass ratio of ZIF precursor, tannic acid solution and anhydrous ethanol is 1:15:20, after stirring evenly, standing for 4 hours, and then separating the solid, washing and drying, and then sintering in a high-temperature furnace, using argon as a protective gas, the sintering temperature is 600 ° C, the sintering time is 3 hours, and ETCH-ZIF powder is obtained after cooling;

[0044] S3, adding hesperidin into anhydrous ethanol, after fully dissolving, adding ETCH-ZIF powder, the mass ratio of ETCH-ZIF powder, hesperidin and anhydrous ethanol is 1:1.2:30, after fully mixing, stirring in the dark for 8h, after the treatment is completed, drying with nitrogen, and then washing and drying to obtain Q-ETCH-ZIF powder;

[0045] S4. Weigh α-casein and glycerol, mix them, and then gradually pour deionized water into them. The mass ratio of casein, glycerol and deionized water is 1:0.35:45. After fully stirring, a casein solution is obtained. Then Q-ETCH-ZIF powder is added. The mass ratio of Q-ETCH-ZIF powder and casein solution is 1:15. After removing bubbles, an antibacterial membrane liquid is obtained.

[0046] Step 3, coating and packaging: soak the pre-treated fruits and vegetables in the antibacterial film liquid for 10 seconds, take them out, dry them at 35°C, seal them in a fresh-keeping bag, and replace the air inside with nitrogen to complete the preservation operation.

[0047] Example 2

[0048] A process for extending the freshness-keeping time of fruits and vegetables at room temperature, comprising the following steps:

[0049] Step 1, pretreatment: soak and wash the picked fruits or vegetables in an aqueous solution of calcium chloride with a mass concentration of 1%, then rinse with clean water, and then dry them in a drying oven at 25°C to obtain pretreated fruits and vegetables;

[0050] Step 2, preparation of antibacterial film solution:

[0051] S1. Weigh cobalt nitrate hexahydrate and add it to anhydrous ethanol. The mass ratio of cobalt nitrate hexahydrate to anhydrous ethanol is 0.29:10. Stir well to obtain a cobalt nitrate solution; weigh 2-methylimidazole and add it to anhydrous ethanol. The mass ratio of 2-methylimidazole to anhydrous ethanol is 0.11:10. Stir well to obtain a 2-methylimidazole solution; mix the cobalt nitrate solution and the 2-methylimidazole solution. The mass ratio of the cobalt nitrate solution and the 2-methylimidazole solution is 1:2. After stirring at room temperature for 1 hour, let stand for 15 hours, and then separate the solid. After washing and drying, a ZIF precursor is obtained;

[0052] S2, tannic acid and deionized water are prepared into a tannic acid solution in a mass ratio of 0.13:10, ZIF precursor and anhydrous ethanol are weighed and mixed, and then the tannic acid solution is added, the mass ratio of ZIF precursor, tannic acid solution and anhydrous ethanol is 1:10:15, after stirring evenly, standing for 2h, and then separating the solid, washing and drying, and then sintering in a high-temperature furnace, using argon as a protective gas, the sintering temperature is 550°C, the sintering time is 2h, and ETCH-ZIF powder is obtained after cooling;

[0053] S3, adding hesperidin into anhydrous ethanol, after fully dissolving, adding ETCH-ZIF powder, the mass ratio of ETCH-ZIF powder, hesperidin and anhydrous ethanol is 1:0.8:20, after fully mixing, stirring in dark for 3h, after the treatment, drying with nitrogen, and then washing and drying to obtain Q-ETCH-ZIF powder;

[0054] S4. Weigh β-casein and glycerol, mix them, and then gradually pour deionized water into them. The mass ratio of casein, glycerol and deionized water is 1:0.25:35. After fully stirring, a casein solution is obtained. Then Q-ETCH-ZIF powder is added. The mass ratio of Q-ETCH-ZIF powder to casein solution is 1:10. After removing bubbles, an antibacterial membrane liquid is obtained.

[0055] Step 3, coating and packaging: spray the antibacterial film liquid on the surface of the pre-treated fruits and vegetables, dry them at 30°C, seal them in a fresh-keeping bag, and vacuum the air inside to complete the preservation operation.

[0056] Example 3

[0057] A process for extending the freshness-keeping time of fruits and vegetables at room temperature, comprising the following steps:

[0058] Step 1, pretreatment: soak and wash the picked fruits or vegetables in an aqueous solution of sodium chloride with a mass concentration of 10%, then rinse with clean water, and then dry them in a drying oven at 45°C to obtain pretreated fruits and vegetables;

[0059] Step 2, preparation of antibacterial film solution:

[0060] S1. Weigh cobalt nitrate hexahydrate and add it to anhydrous ethanol, the mass ratio of cobalt nitrate hexahydrate to anhydrous ethanol is 0.58:20, and stir to obtain a cobalt nitrate solution; weigh 2-methylimidazole and add it to anhydrous ethanol, the mass ratio of 2-methylimidazole to anhydrous ethanol is 0.22:20, and stir to obtain a 2-methylimidazole solution; mix the cobalt nitrate solution and the 2-methylimidazole solution, the mass ratio of the cobalt nitrate solution to the 2-methylimidazole solution is 1:5, stir at room temperature for 2 hours, let stand for 20 hours, and then separate the solid, wash and dry to obtain a ZIF precursor;

[0061] S2, tannic acid and deionized water are prepared into a tannic acid solution in a mass ratio of 0.26:20, ZIF precursor and anhydrous ethanol are weighed and mixed, and then the tannic acid solution is added, the mass ratio of ZIF precursor, tannic acid solution and anhydrous ethanol is 1:20:25, after stirring evenly, standing for 6 hours, and then separating the solid, washing and drying, and then sintering in a high-temperature furnace, using argon as a protective gas, the sintering temperature is 650 ° C, the sintering time is 4 hours, and ETCH-ZIF powder is obtained after cooling;

[0062] S3, adding hesperidin into anhydrous ethanol, after fully dissolving, adding ETCH-ZIF powder, the mass ratio of ETCH-ZIF powder, hesperidin and anhydrous ethanol is 1:1.6:40, after fully mixing, stirring in dark for 10 hours, after the treatment is completed, drying with nitrogen, and then washing and drying to obtain Q-ETCH-ZIF powder;

[0063] S4. Weigh α-casein or β-casein and mix with glycerol, then gradually pour deionized water therein, the mass ratio of casein, glycerol and deionized water is 1:0.5:55, after fully stirring, a casein solution is obtained, and then Q-ETCH-ZIF powder is added, the mass ratio of Q-ETCH-ZIF powder to casein solution is 1:20, after defoaming, an antibacterial membrane liquid is obtained.

[0064] Step 3, coating and packaging: spray the antibacterial film liquid on the surface of the pre-treated fruits and vegetables, blow dry with nitrogen, place in a fresh-keeping bag and seal it, and vacuum the air inside to complete the preservation operation.

[0065] Comparative Example 1

[0066] A process for preserving fruits and vegetables is different from Example 1 in that the preparation of the antibacterial film liquid is different. The preparation process of the antibacterial film liquid in this comparative example is:

[0067] Weigh α-casein and glycerol, mix them, then gradually pour deionized water into them, the mass ratio of casein, glycerol and deionized water is 1:0.35:45, stir them thoroughly to obtain a casein solution, and after removing bubbles, obtain an antibacterial membrane solution.

[0068] Comparative Example 2

[0069] A process for preserving fruits and vegetables is different from Example 1 in that the preparation of the antibacterial film liquid is different. The preparation process of the antibacterial film liquid in this comparative example is:

[0070] Weigh α-casein and glycerol and mix them, then gradually pour deionized water into them, the mass ratio of casein, glycerol and deionized water is 1:0.35:45, after fully stirring, a casein solution is obtained, and then ZIF powder is added. The preparation of ZIF powder is the same as step S1 of Example 1, the mass ratio of ZIF powder to casein solution is 1:15, and after defoaming, an antibacterial membrane liquid is obtained.

[0071] Comparative Example 3

[0072] A process for preserving fruits and vegetables is different from Example 1 in that the preparation of the antibacterial film liquid is different. The preparation process of the antibacterial film liquid in this comparative example is:

[0073] Weigh α-casein and glycerol and mix them, then gradually pour deionized water into them, the mass ratio of casein, glycerol and deionized water is 1:0.35:45, after fully stirring, a casein solution is obtained, and then hesperidin and ZIF powder are added. The preparation of ZIF powder is the same as step S1 of Example 1, and the mass ratio of ZIF powder, hesperidin and casein solution is 1:1.2:15. After defoaming, an antibacterial film liquid is obtained.

[0074] Experimental example

[0075] In order to more clearly illustrate the present invention, 20 Dashahe Red Fuji apples from Fengxian County of similar size, without bruises and pests were selected and divided into four parts. The apples were treated by the process of Example 1 and Comparative Examples 1-3 respectively. Then, the apples were placed in a dark environment at room temperature and humidity (20±2°C; 65±10%RH) for 7-30 days. The color, weight loss rate and rot rate were tested at 7 days, 15 days and 20 days respectively. The results were recorded. The results are shown in the following table:

[0076]

[0077]

[0078] As can be seen from Table 1, the apples treated by the treatment process of Example 1 had a slight loss of gloss on the surface, but no shrinkage or softening, no rot, and a weight loss rate of only 1.0% on the 30th day; the apples of Comparative Examples 1 and 2 had a large degree of gloss loss, shrinkage and softening on the surface, and the weight loss rate was greater than 2%, and the rot rate was higher than 8% on the 30th day; although Comparative Example 3 was better than Comparative Examples 1-2, it was still larger than Example 1, especially on the 30th day. In summary, it is shown that the apples treated by the treatment process of Example 1 of the present invention can be stored for a longer time at room temperature.

[0079] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms should not be understood as necessarily being directed to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification.

[0080] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A process for extending the freshness-keeping time of fruits and vegetables at room temperature, characterized in that: The following steps are involved: Step 1, pre-treatment: soak and wash the picked fruits or vegetables with salt water, then rinse with clean water, and then place them in a drying oven for drying to obtain pre-treated fruits and vegetables; Step 2, preparing antibacterial film liquid: preparing ZIF precursor; then treating it with tannic acid to obtain ETCH-ZIF powder; Then, hesperidin was added to obtain Q-ETCH-ZIF powder; finally, casein solution was added to obtain antibacterial membrane solution; Step 3, coating and packaging: soak the pre-treated fruits and vegetables in the antibacterial film liquid, or spray the antibacterial film liquid on the surface of the pre-treated fruits and vegetables. After drying, place them in a fresh-keeping bag and seal them to complete the preservation operation.

2. A process for extending the freshness-keeping time of fruits and vegetables at room temperature according to claim 1, characterized in that: In the first step, the salt water is an aqueous solution of sodium chloride or calcium chloride with a mass concentration of 1%-10%; the temperature of the drying box is 25-45°C.

3. A process for extending the freshness-keeping time of fruits and vegetables at room temperature according to claim 1, characterized in that: In the second step, the preparation process of the ZIF precursor includes: Weigh cobalt nitrate hexahydrate, add it into anhydrous ethanol, and stir to obtain a cobalt nitrate solution; weigh 2-methylimidazole, add it into anhydrous ethanol, and stir to obtain a 2-methylimidazole solution; mix the cobalt nitrate solution and the 2-methylimidazole solution, stir at room temperature for 1-2 hours, let stand for 15-20 hours, and then separate the solid, wash and dry to obtain a ZIF precursor.

4. A process for extending the freshness-keeping time of fruits and vegetables at room temperature according to claim 3, characterized in that: In the cobalt nitrate solution of step 2, the mass ratio of cobalt nitrate hexahydrate to anhydrous ethanol is 0.29-0.58:10-20; in the 2-methylimidazole solution of step 2, the mass ratio of 2-methylimidazole to anhydrous ethanol is 0.11-0.22:10-20; and the mass ratio of cobalt nitrate solution to 2-methylimidazole solution is 1:2-5.

5. The process for extending the freshness-keeping time of fruits and vegetables at room temperature according to claim 1, characterized in that: In the second step, the preparation process of ETCH-ZIF powder includes: Weigh the ZIF precursor and anhydrous ethanol, mix them, then add the tannic acid solution, stir evenly, let it stand for 2-6 hours, then separate the solid, wash and dry it, and then sinter it in a high-temperature furnace, and obtain ETCH-ZIF powder after cooling; wherein the tannic acid solution is tannic acid and deionized water in a mass ratio of 0.13-0.26:10-20; the mass ratio of the ZIF precursor, the tannic acid solution and the anhydrous ethanol is 1:10-20:15-25.

6. A process for extending the freshness-keeping time of fruits and vegetables at room temperature according to claim 5, characterized in that: In the second step, the sintering temperature in the high temperature furnace is 550-650° C., the sintering time is 2-4 hours, and argon is used as the protective gas during the sintering process.

7. The process for extending the freshness-keeping time of fruits and vegetables at room temperature according to claim 1, characterized in that: In the second step, the preparation process of Q-ETCH-ZIF powder includes: Hesperidin is added into anhydrous ethanol, and after it is fully dissolved, ETCH-ZIF powder is added, and after being fully mixed, it is stirred in the dark for 3-10 hours. After the treatment, it is dried by nitrogen blowing, and then washed and dried to obtain Q-ETCH-ZIF powder; wherein the mass ratio of ETCH-ZIF powder, hesperidin and anhydrous ethanol is 1:0.8-1.6:20-40.

8. The process for extending the freshness-keeping time of fruits and vegetables at room temperature according to claim 1, characterized in that: In the second step, the preparation process of the antibacterial film liquid includes: Weigh casein and glycerol, mix them, then gradually pour deionized water into them, stir them thoroughly to obtain a casein solution, then add Q-ETCH-ZIF powder, remove bubbles, and obtain an antibacterial membrane liquid; wherein the mass ratio of casein, glycerol and deionized water is 1:0.25-0.5:35-55; the mass ratio of Q-ETCH-ZIF powder and casein solution is 1:10-20.

9. The process for extending the freshness-keeping time of fruits and vegetables at room temperature according to claim 1, characterized in that: In the third step, the drying is carried out by blowing with nitrogen or drying at 30-40°C.

10. The process for extending the freshness-keeping time of fruits and vegetables at room temperature according to claim 1, characterized in that: Before sealing the fresh-keeping bag, replace the air inside with nitrogen or vacuum it.

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