CN112205459A

CN112205459A - Grape flowing phase antiseptic fresh-keeping technology and equipment

Info

Publication number: CN112205459A
Application number: CN202010840887.0A
Authority: CN
Inventors: 李喜宏; 贾晓昱; 陈兰
Original assignee: Dayouwei Tianjin Cold Chain Equipment Co ltd
Current assignee: Dayouwei Tianjin Cold Chain Equipment Co ltd
Priority date: 2020-08-20
Filing date: 2020-08-20
Publication date: 2021-01-12

Abstract

The invention relates to a grape fluid phase anticorrosion and fresh-keeping technology and equipment, which are characterized by quality control before harvesting, non-damage harvesting, simple tunnel high-humidity differential pressure precooling, fluid phase anticorrosion storage in a phase temperature warehouse and SO during the storage period₂Fumigating with intermittent flow phase. The storage period and the quality of the grapes are obviously improved.

Description

Grape flowing phase antiseptic fresh-keeping technology and equipment

Technical Field

The invention belongs to the field of fruit preservation, relates to grapes, and particularly relates to a flow phase preservative and fresh-keeping method for grapes.

Background

Grapes are typical fresh food varieties, and have large fruit grains, hard and crisp pulp and rich nutrition. But the rotting loss caused by the technical improper collection, packaging, storage and the like accounts for more than 20 percent of the total yield every year. The main reasons are that mechanical injury is easy to generate in the process of harvesting and transporting; the peel is thin, the waxy structure of the peel is loose, and the peel is easily damaged by the preservative; the taste is sweet and juicy, the water content is more than 80%, the stem is easy to dry, the stem is easy to wither and brown, and the edible value and the commodity value are lost; susceptible to mold infestation. SO since the 20 s of the 19 th century₂It is used for keeping grapes fresh. The specific application method comprises sulfur combustion fumigation, large net fumigation, sulfite preservative tablet slow release, and sulfur combustion fumigation process SO₂The concentration can not be accurately controlled and the environment is polluted. The sulfite preservative tablets and powder are influenced by the formula, process, use standard, use dosage, placement position and sealing property of a packaging bag, and the pesticide effect is often unevenly released, the pesticide injury is caused, the bleaching is caused, the mildew and rot are caused, the peculiar smell is caused, and the like.

CN103988894A discloses a grape preservative, which comprises the following components: beta-aminobutyric acid 0.05-0.1 g/L, vitamin C3.0-6.0 g/L, CaCl₂2.0-4.0 g/L, 3.0-6.0 g/L tartaric acid, 50-80 g/L fructose, and the balance water. Experiments prove that the grape preservative has a good preservation effect on various grape varieties such as summer black, Kyoho, beauty finger, Guigong and the like, can reduce the rotting rate of fruits, reduce the content of soluble solids (TSS) of the fruits, reduce the spike-axis browning index and obviously prolong the storage period of the grapes.

The patent adopts a compound bacteriostatic agent, and has a certain bacteriostatic effect. However, the soaking type preservation process is complex, the air drying is difficult, the moisture is remained, and the mold is easy to breed in the storage period.

CN103947746A provides a method for grape preservation or grape gray mold resistance, comprising the following steps: the picked grape fruits are soaked in a cinnamic acid solution to realize the preservation of the grapes or the resistance to gray mold. The cinnamic acid solution comprises cinnamic acid and water, and the final concentration of the cinnamic acid in the cinnamic acid solution is 1-10 mM. Experiments prove that the invention can realize the fresh keeping of the picked grape fruits by utilizing the cinnamic acid solution and achieve the effect of resisting gray mold.

The cinnamic acid solution has a certain sterilization effect. However, the soaking type preservation process is complex, the air drying is difficult, the moisture is remained, and the mold is easy to breed in the storage period.

CN104509585A discloses a grape film-coating preservation method, which solves the problems of the prior art that grape preservation method can cause harm to human body, the safety is poor, and the quality of stored grapes is poor, and comprises the following steps: (1) preparation of modified Nano SiO₂(ii) a (2) Preparing a composite coating preservative; (3) soaking in an agent to form a film; (4) and (5) pre-cooling and preserving.

The patent adopts nano SiO₂Has certain bacteriostasis effect. But the coating preservation process is complex and the cost is high; the sterilization effect of the coating preservation is difficult to ensure.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a fluid phase preservation and fresh-keeping method for grapes, so that the storage period and the storage quality of the grapes are improved.

The technical scheme adopted by the invention for solving the technical problem is as follows:

a grape fluid phase preservation and fresh-keeping method comprises the following steps:

(1) regulating and controlling quality before mining;

(2) harvesting without injury;

(3) precooling the tunnel in a high-humidity differential pressure manner;

(4) fluid phase antiseptic storage in phase temperature storage, SO during storage₂Fumigating with intermittent flow phase.

Moreover, the pre-harvest quality regulation and control is to spray a quality inducer on the surfaces of leaves and fruits within 15 days before harvest, wherein the quality inducer consists of a component A and a component B, the component A is sprayed firstly, the component B is sprayed every other day, the components are diluted by 300 times and are respectively sprayed for 1-3 times;

the preparation method of the component A comprises the following steps: dissolving L-Arg0.1-0.3 g/L, 10-20 mmol/L linoleic acid, MeSA3.0-8.0 mg/L and CyS3.0-5.0 mg/L in water according to a preset requirement, stirring for 15-20 min at 35-55 ℃, adding 0.2-0.6 g/L zinc acetate and 1-3 g/L calcium chloride into the obtained solution, uniformly stirring, and finally adding 0.5-1.0 g/L SOD preparation into the solution to obtain a mixed solution with a constant volume of 1L;

the preparation method of the component B comprises the following steps: dissolving BR 0.1-0.5 mg/L, indoleacetic acid 0.2-0.4 mg/L, gibberellic acid 10-30 mg/L, brassinolide 0.1-1.0 mg/L, MeJA 3-5 mg/L and hydrogen peroxide 10-20 mg/L with a small amount of ethanol, adding the mixture into water, stirring the mixture at 35-55 ℃ until the mixture is uniformly dissolved to form a mixed intercalation solution, adding sodium nitroprusside 5-10 mmol/L, carrying out ultrasonic treatment at 30-50 kHz for 10-20 min, and fixing the volume to 1L to obtain an intercalation mixed solution B.

And the non-damage harvesting is carried through the non-damage turnover box, the storage bin body structure of the non-damage turnover box is in a circular arc shape, a drain hole is formed in the bottom of the middle of the storage bin, the inner surface of the storage bin is a five-layer composite fresh-keeping pad which comprises a blocking layer, a pesticide application layer, a pesticide carrying layer, an adsorption layer and an anti-fog layer which are sequentially arranged, and all the layers are combined together in a bonding mode.

Moreover, the barrier layer is non-woven fabric, the pesticide application layer is a microencapsulated plant essential oil preservative, the pesticide carrying layer is one of a polypropylene film or a polyethylene film, the adsorption layer is composed of 5-8 wt% of 1-methylcyclopropene, 94-91 wt% of potassium permanganate and 1 wt% of polyacrylate, and the antifogging layer is laminating paper.

Moreover, the wall-core ratio of the microencapsulated plant essential oil preservative is 4: 1, and the core material is clove essential oil: the cinnamon essential oil is composed of wall materials of 50 wt% of beta-cyclodextrin, 40 wt% of chitosan and 10 wt% of tween 80 according to the volume ratio of 1: 1.

Moreover, the box wall of the turnover box is of a sandwich structure, the side wall of the turnover box is provided with an openable vent hole, and the interlayer is internally provided with a coolant according to actual needs.

And, the simple and easy high wet differential pressure precooling in tunnel be in the freezer, put the naked fruit of grape on the tray in a basket yard, the tray is put in static pressure case trompil one side, hug closely the static pressure case, align in proper order and discharge, cover tight with PVC cloth the goods pile the top and the side, when the fan rotates, produce the negative pressure in the static pressure case, the cold air in the suction freezer, the cold air is from the tail portion of goods pile cross-flow entering static pressure case, static pressure case top installation two axial fans, the positive trompil of static pressure case, the humidifier is installed to the static pressure incasement.

Furthermore, 1 muL/L1-MCP is used for treatment in the precooling process, and the treatment time is 12 h.

And the phase temperature storehouse flow phase anticorrosion storage is to put the grapes into the phase temperature storehouse, the phase temperature storehouse is of a primary-secondary jacket structure, the evaporator is installed on the primary storehouse, cold air blown out by the evaporator transmits cold energy into the secondary storehouse through an aluminum plate of the secondary storehouse, the secondary storehouse is airtight, a flow phase anticorrosion system is installed on the secondary storehouse, and flow phase wind speed treatment is adopted.

And, said SO₂Intermittent fluid phase fumigating for removing primary SO₂Circulating fumigation with concentration of 10000ppm for 30min, then circulating fumigation with 2000ppm for 30min every 15 days, and synchronously starting fluid phase anticorrosion equipment in the fumigation process.

The invention has the advantages and positive effects that:

(1) the quality is controlled before picking, molecules in the temporary picking period co-excite a physiological and pathological regulator, the hardness of the fruits is improved, the respiratory strength and ethylene ripening and turning red are inhibited, aging, alcoholization and water loss softening are delayed, and a foundation is laid for improving the storage resistance and shelf life of the fruits.

(2) The non-damage harvesting adopts a field non-damage packaging turnover box to prevent mechanical damage and has the functions of corrosion resistance and ethylene antagonism.

(3) And (3) rapidly removing field heat by using a simple tunnel high-humidity differential pressure precooling device, so that the temperature of the fruits is reduced to below 5 ℃ after the fruits are picked for 5-6 hours, and the high-humidity precooling is cooperated with the 1-MCP fumigation treatment to reduce water loss and simultaneously complete the anti-aging treatment.

(4) And (4) preserving and storing the fluid phase in a phase temperature storage. The heat and mass transfer technology system with primary and secondary phase separate control is created for the first time, and 15 new technologies of no-humidification constant humidity, evaporator frostless, precise temperature control fluctuation less than +/-0.1 ℃, constant temperature and humidity air conditioning, pulse atomization corrosion prevention low residue, flow phase corrosion prevention zero residue, in-situ tunnel differential pressure precooling, normally closed and normally open linkage, full utilization of natural cold source, full utilization of bioenergy, zero phase change of biological membrane, zero corrosion of equipment, intelligent control based on fresh-keeping core and internet + internet of things + remote diagnosis and the like are broken through.

(5) The flow phase wind speed internal circulation treatment can obviously inhibit the hypha growth of botrytis cinerea to reduce the diameter of lesion. The content of VC in grapes treated by the 1.5m/s fluid phase wind speed is higher than that of the control, and the fluid phase wind speed treatment induces the activity of grape defense related enzymes including CAT, TAL, POD, SOD, GIU and CHI. In addition, the flow phase air velocity treatment can better maintain the quality loss of the grape fruits, the hardness of the fruits, the Titratable Acid (TA), the Total Soluble Solids (TSS) and other nutritional qualities. The wind speed mainly improves the storage quality of the grapes by damaging botrytis cinerea hyphae and spore structures and improving the disease resistance of the grapes.

(6) Aiming at the problems that the release of sulfur dioxide for antisepsis and fresh preservation of fresh grapes cannot be accurately controlled, phytotoxicity is easy to generate and the like, SO is adopted₂The intermittent fluid phase fumigation technology can obviously improve the storage period and the quality of the grapes, and the storage period is more than 6 months in the case of red globe grapes. SO (SO)₂Intermittent fluid phase fumigation, first SO₂Circulating fumigation with concentration of 10000ppm for 30min, then circulating fumigation with 2000ppm for 30min every 15 days, and synchronously starting fluid phase anticorrosion equipment in the fumigation process. The technology can keep titratable acid content and cell membrane integrity, red globe grape is stored for 180 days, the rotting rate is only 3.9%, the bleaching index is 0.3, the residual quantity of sulfur dioxide is 3.1mg/kg and is lower than the FDA limit, and the storage effect is good.

Drawings

FIG. 1 is a structural view of a non-damaged transfer container;

FIG. 2 is a schematic structural view of a composite freshness protection mat;

FIG. 3 is a schematic view of a plenum box configuration;

FIG. 4 is an effect diagram of a double-pile longitudinal gapless differential pressure precooled object placement mode;

FIG. 5 is a 6 m double-stack longitudinal gapless differential pressure precooling and cooling curve diagram;

FIG. 6 is a plan view of a parallel phase temperature store;

FIG. 7 is a sectional view taken along line A-A of FIG. 6;

FIG. 8 is a sectional view taken along line B-B of FIG. 6;

FIG. 9 is a temperature field profile of the phase temperature banks (A, B) and the cold storages (C, D) at heights of 0.5m and 3.5 m;

FIG. 10 is a graph of the effect of wind speed on grape gray mold damage diameter;

FIG. 11 is a graph of the effect of streaming phase wind velocity treatment on Botrytis cinerea symptoms;

FIG. 12 is a graph of the effect of flow phase wind velocity treatment on Botrytis cinerea structures;

FIG. 13 is a graph of the effect of fluid phase wind velocity treatment on grape fruit defense enzyme activity, wherein (A) CAT enzyme activity; (B) PAL enzyme activity; (C) POD enzyme activity; (D) SOD enzyme activity; (E) GLU enzyme activity; (F) CHI enzyme activity.

FIG. 14 is a schematic diagram of the operation of an intermittent fumigation flow phase corrosion prevention device based on a phase temperature reservoir;

FIG. 15 shows the titratable acid content of red globe grapes in different treatment groups during storage;

FIG. 16 is a graph showing the relative conductivity content change of red globe grapes in different treatment groups during storage;

FIG. 17 shows the change of PPO activity of red globe grapes in different treatment groups during storage;

FIG. 18 shows the change in POD activity of red globe grapes in different treatment groups during storage;

FIG. 19 shows the change in MDA content of red globe grapes in different treatment groups during storage;

FIG. 20 shows SO in red globe grape storage period₂Change in residual amount.

Detailed Description

The present invention is further illustrated by the following specific examples, which are intended to be illustrative, not limiting and are not intended to limit the scope of the invention.

1. pre-harvest quality control

(1) The application method is disclosed. Spraying a quality inducer on the surfaces of leaves and fruits within 15 days before harvesting, wherein the inducer comprises a quality improver A and a quality inducer B which have synergistic effects on the components, so that the plant absorption effect is improved, the fruit ripening is promoted, and the qualities such as color, sugar degree, brittleness and the like are improved. The component A is firstly sprayed, the component B is sprayed every other day, and the components are diluted by 300 times and are respectively sprayed for 1 to 3 times.

(2) And (4) preparing. Comprises A, B, wherein the A component comprises 0.1-0.3 g/L of L-Arg (L-arginine), 0.2-0.6 g/L, SOD preparation of zinc acetate 0.5-1.0 g/L, 1-3 g/L of calcium chloride, 10-20 mmol/L, MeSA (methyl salicylate) of linoleic acid 3.0-8.0 mg/L, CyS (cystine) of 3.0-5.0 mg/L; the component B comprises 0.1-0.5 mg/L of BR (brassinolide), 10-30 mg/L of gibberellic acid, 0.1-1.0 mg/L of brassinolide, 10-20 mg/L, MeJA (methyl jasmonate) 3-5 mg/L of hydrogen peroxide, 5-10 mmol/L of sodium nitroprusside:

(3) preparation process

The component A comprises: dissolving 0.1-0.3 g/L of L-Arg (L-arginine), 10-20 mmol/L, MeSA (methyl salicylate) and 3.0-8.0 mg/L, CyS (cystine) into water according to a preset requirement, stirring for 15-20 min at 35-55 ℃, then adding 0.2-0.6 g/L of zinc acetate and 1-3 g/L of calcium chloride into the obtained solution, uniformly stirring, and finally adding a mixed solution of 0.5-1.0 g/L of SOD preparation and constant volume to 1L into the solution;

the component B comprises:

dissolving 0.1-0.5 mg/L BR (brassinolide), 0.2-0.4 mg/L indoleacetic acid, 10-30 mg/L gibberellic acid, 0.1-1.0 mg/L, MeJA (methyl jasmonate) and 10-20 mg/L hydrogen peroxide in a small amount of ethanol, adding the mixture into water, stirring the mixture at 35-55 ℃ until the mixture is uniformly dissolved to form a mixed intercalator solution, adding 5-10 mmol/L sodium nitroprusside, carrying out ultrasonic treatment at 30-50 kHz for 10-20 min, and fixing the volume to 1L to obtain an intercalated mixed solution B:

2. harvesting

The water is strictly forbidden in 10-15 days before harvesting, and harvesting needs to be delayed for 8-10 days if heavy rain occurs. The fruits are stored for a long time, the harvest maturity is 7-8 percent and the fruits are ripe, and generally the fruits are colored by 50-60 percent. The fruits stored for a long time are manually picked, lightly taken and lightly placed, directly placed into a fruit picking bag after picking, and then placed into a non-damage turnover box.

The turnover box is free of damage, the appearance of the box body is square, as shown in figure 1, the main body structure of the internal storage bin 2 is arc-shaped, the collision and extrusion of grapes in the transportation and turnover processes are reduced, the grapes can be integrally molded through injection molding, a drain hole 1 is formed in the bottom of the middle of the grape, and the arc-shaped surface is a five-layer composite fresh-keeping pad which comprises a blocking layer 4, a pesticide applying layer 5, a pesticide carrying layer 6, an adsorption layer 7 and an anti-fog layer 8 which are sequentially arranged as shown in figure 2. Wherein, the barrier layer is non-woven fabrics. The application layer is a microencapsulated plant essential oil preservative with the wall-core ratio of 4: 1, and the core material is clove essential oil: cinnamon essential oil is 1:1 (volume ratio), and the wall material consists of 50 wt% of beta-cyclodextrin, 40 wt% of chitosan and 10 wt% of homogeneous phase emulsifier (polyoxyethylene sorbitan monooleate, which is called polysorbate-80 or tween-80 for short). The drug-loaded layer is one of a polypropylene film or a polyethylene film. The adsorption layer consists of 5-8 wt% of 1-methylcyclopropene, 94-91 wt% of potassium permanganate and 1 wt% of polyacrylate, and the antifogging layer is laminating paper.

The box wall of turnover case is sandwich structure, and the design of lateral wall has open-type ventilation hole 3, can place the coolant according to actual need in the interlayer (the box wall ventilation hole is closed this moment), also can be used to the fruit vegetables ventilation (do not place the coolant, the box wall ventilation hole is opened this moment).

3. Simple tunnel high-humidity differential pressure precooling

The simple tunnel differential pressure high humidity precooling system includes plastic tent, static pressure box, axial flow type exhaust fan and fumigating and humidifying device. The main body of the system is a static pressure box 9, two axial flow fans 10 are installed at the top of the static pressure box, a rectangular hole 11 is formed in the front face of the static pressure box, and a humidifier is installed in the static pressure box, so that the environmental humidity in the humidification process can be controlled quantitatively at regular time, and the humidity in a precooling process storehouse is kept at 90-95%. The length, width and height of the static pressure box are 3500mm, 400mm and 2100mm respectively, the middle position of the front surface of the static pressure box is provided with a rectangular air inlet hole of 600mm multiplied by 1600mm, the edge of the hole is 100mm away from the ground, and the top of the static pressure box is provided with two air volumes of 11000m³The structure diagram of the static pressure box is shown in figure 3.

The use method comprises the following steps: naked fruit of fruit vegetables basket 13 is put things in good order on tray 14, and the tray is put on static pressure case trompil one side, hugs closely the static pressure case, aligns in proper order and discharges, hides tight with PVC cloth 12 above the goods heap and side. When the fan rotates, negative pressure is generated in the static pressure box, cold air in the refrigeration house is sucked, and the cold air flows through the tail of the cargo pile and enters the static pressure box, so that the aim of precooling fruits and vegetables is fulfilled. And in the precooling process, 1 mu L/L1-MCP is used for treatment at the same time, the ethylene is antagonized, and the treatment time is 12 h. The fruit is put into the basket, and the size of single basket is: length × width × height is 500mm × 500mm × 170mm, the packaging amount per basket is about 15kg, and the tray size is: length is 1000mm wide for 1500mm, and the tray puts 6 baskets of grape on every layer, puts 11 layers totally, and like this, individual tray goods size is: length × width × height is 1500mm × 1000mm × 2100mm, and the weight of the cargo is about 1000 kg. A differential pressure precooling goods placing mode: 6 meters of longitudinal gapless placement: double pile, longitudinal, gapless, parallel arrangement, total 8 trays. Namely, the width of the long dragon pile is 2000mm, the height of the long dragon pile is 2100mm, the distance between the two long dragon piles is zero (close), the length of the dragon is 6000mm, and 8t of goods can be placed in the long dragon pile, as shown in figure 4.

Before goods are placed, a temperature sensor of a wireless temperature measuring system is inserted into a fruit core to monitor the temperature of the fruit. The number of the temperature probes is 19, one of the temperature probes is placed in the cold storage, the temperature of the cold storage is monitored, and the rest of the temperature probes are respectively placed at different parts of the cargo pile: the length direction of the cargo pile is divided into front (close to the static pressure box), middle and rear (long dragon tail part) on average; the height direction is divided into: an upper layer, a middle layer and a lower layer; the width direction is divided into an inner side and an outer side. The temperature probes are arranged at the points of front, middle, back, upper, middle, lower, inner and outer intersection, and the total number of the probes is 18, so that the temperature change of the fruit core is monitored. The shutdown temperature of a fan of the refrigeration house is set to be-2 ℃, and the return temperature difference is 1 ℃. Compared with common static precooling, 8 whole trays of fruits are scattered in a common cold storage, and the interval between the trays is 1 meter, so that the fruits can be in contact with more cold air. As can be seen from FIG. 5, on average 5-6h dropped to 0 ℃.

4. Phase temperature storage

Storing at a phase temperature, accurately controlling the temperature to +/-0.1 ℃, and keeping constant humidity without humidification. The phase temperature warehouse structure mainly comprises a mother warehouse 17, a phase temperature warehouse ground 20, a sub warehouse 16 and a sub warehouse internal circulation ventilation system 19.

(1) The phase temperature warehouse is of a primary-secondary jacket structure, and the heat insulation material of the warehouse body of the primary warehouse is high-density polyurethane double-sided color with the thickness of 150mmSteel plate (volume weight 40 kg/m)³) The mother storeroom is airtight and heat-insulated and is provided with a standard air regulating valve, as shown in figure 6.

(2) The plate of the sub-warehouse uses a 1mm thick aluminum plate, the air tightness of the sub-warehouse is not insulated, the distance between the sub-warehouse and the sub-warehouse is 500mm, the distance between the top of the sub-warehouse is 1000mm, 1 ventilation and operation window 18 of the sub-warehouse is respectively arranged at the two sides of the sub-warehouse adjacent to the door, the sub-warehouse and the sub-warehouse are combined to carry out large-amplitude heat exchange, the plate can also be used as a maintenance operation window, and the flowing phase anticorrosion system is arranged on the.

Temperature fluctuation of a traditional refrigeration house and a phase temperature storage house is respectively measured, random variation of the temperature fluctuation can cause the central temperature of frozen agricultural products to temporarily reduce below a threshold level, and cold damage can occur when the central temperature exceeds the threshold. In addition, temperature fluctuations may exacerbate moisture condensation, leading to microbial growth and fruit decay. The temperature distributions of 0.5 and 3.5m high planes in the cold store and the phase temperature store were measured, respectively. When the temperature is set to 0 ℃, the temperature fluctuation of the phase temperature store is very small in fig. 9 (a, B) and is only ± 0.1 to ± 0.2 ℃ compared with ± 0.5 to ± 1.0 ℃ of (C, D) in the cold store fig. 9. The temperature of the cold storage is controlled by refrigeration equipment, a direct cooling mode is adopted, and cold air blown out from the evaporator 15 directly contacts products in the cold storage. The cold energy of the sub-reservoirs of the phase temperature reservoir is cooled by air flowing through the enclosed spaces or jackets around the walls, floor and ceiling of the interior reservoir, rather than by direct circulation of the air within the room. By adding an internal structure, direct contact of the product with the evaporator is avoided, and low temperature fluctuation of the internal room is maintained.

5. Shelf life fluid phase corrosion protection

The main utilization of the internal circulation of the fluid phase wind speed has obvious anticorrosion effect and is cooperated with SO₂Intermittent fumigation flow phase anticorrosion treatment is carried out, and the anticorrosion effect is improved.

5.1 the internal circulation of the fluid phase wind speed has obvious inhibiting effect on grape gray mold

The internal circulation of the flow phase wind speed is realized by a flow phase antiseptic system (figure 7) on a phase temperature warehouse, and experiments show that the 1.5m/s flow phase wind speed treatment can inhibit the hypha growth of botrytis cinerea so as to obviously reduce the diameter of lesion. The content of VC in grapes treated by the 1.5m/s fluid phase wind speed is higher than that of a control, and the fluid phase wind speed treatment induces the activity of grape defense related enzymes including CAT, TAL, POD, SOD, GIU and CHI. In addition, the flow phase air velocity treatment can better maintain the quality loss of the grape fruits, the hardness of the fruits, the Titratable Acid (TA), the Total Soluble Solids (TSS) and other nutritional qualities. The wind speed mainly improves the storage quality of grapes by damaging hypha and spore structures of botrytis cinerea and improving the disease resistance of grape fruits, and although the flowing-phase wind speed treatment cannot sterilize pathogenic fungi, the flowing-phase wind speed treatment can inhibit the activity of the fungi and improve the disease resistance of fruits and vegetables.

(1) Influence of fluid phase wind speed treatment on grape gray mold bacterial plaque diameter

As shown in FIG. 10, the CK group (control group, 0m/s wind velocity treated group) and the AFIC group (1.5m/s flow phase wind velocity treated group) showed an increase in the lesion diameter of the fruit after inoculation during storage. The foci treated with AFIC were significantly smaller in diameter than CK. The disease diameters of CK at 20d, 30d and 40d are respectively 0.23cm, 0.62cm and 1.02 cm. The diameters of the lesions of the flow phase wind speed treatment group are respectively 0.02, 0.32 and 0.55cm, which is obviously lower than that of the control group (P < 0.05). Compared with the control, the diameter of the grape lesion was reduced by 91.3%, 48.4% and 46.1%, respectively. This shows that the fluid phase wind velocity treatment can effectively inhibit the growth of Botrytis cinerea at 0 deg.C, and reduce the diameter of lesion. This is probably due to the air flow resistance bending the conidia, resulting in a reduction in spore release.

(2) Effect of fluid phase wind velocity treatment on Gray mildew symptoms of grapes

The severity of disease in both the CK and AFIC groups increased with increasing storage time (fig. 11). However, the wind speed treatment was effective in controlling grape gray mold, and the CK group was significantly expanded at 0 ℃ after 30 days of inoculation with Botrytis cinerea. The plaque diameter in AFIC group is significantly lower in 30d and 40d than in CK group. The results show that the fluid phase wind velocity treatment has an inhibiting effect on botrytis cinerea, which may be related to the direct antifungal capability of the fluid phase wind velocity treatment on botrytis cinerea, and that the wind velocity potential antifungal activity may be related to the damage of hyphae and spores of botrytis cinerea according to the wind velocity in-vitro antifungal activity results, and in order to confirm the hypothesis, the scanning electron microscope is used for observing the form of the hyphae of the botrytis cinerea.

(3) Influence of flow phase wind speed on Gray mold morphology

The hypha morphology of the fluid phase wind velocity treated group and CK group Botrytis cinerea after storage for 40 days is shown in FIG. 12. CK group hyphae are uniform in size, smooth, compact and complete in surface. On the contrary, the botrytis cinerea treated by wind speed has the defects of cell atrophy, spore falling, collapse, hypha distortion, atrophy and sparseness, hypha reduction and small-block broken part of hypha. The fluid phase wind velocity treatment causes damage to group hyphae and spores. The results indicate that AFIC treatment can destroy the integrity of Botrytis cinerea and alter cell surface morphology. The wind speed treatment damages the integrity of the cell membrane of the botrytis cinerea, and meanwhile, the deformation of the hypha form can cause the imbalance of the intracellular osmotic pressure and the leakage of the cell content, thereby causing cell damage. The viability of spores is easily influenced by external pressure factors such as air flow, oxygen, etc., and the change in hyphal morphology may be associated with damage to cell membranes and leakage of cellular material, which leads to retardation of enzymatic reactions and leakage of cytoplasm, which may further lead to fungal cell necrosis.

(4) Influence of fluid phase wind velocity on grape fruit defense enzyme activity

Defensive enzymes are involved in the biosynthesis of various signaling molecules in plant tissues. Compared with the control treatment, the activity of the wind speed-treated grape CAT enzyme is obviously improved, the CAT activity of the wind speed-treated group is obviously improved after being stored for 10 days (P <0.05), reaches a peak value at 20d, is 5.12Ug-1 and then declines, but the activity is obviously higher than that of the control group (A in figure 13). PAL activity of the control group and the wind speed treatment group is increased and then decreased (B in figure 13), the wind speed treatment can effectively improve the activity of PAL in the storage period, at 10d, 20d and 40d, the PAL activity of the fruit processed by wind speed is obviously higher than CK, which is 2 times, 2.3 times and 1.5 times of CK respectively, and the PAL peak value of the wind speed group is 14% higher than that of CK group. The POD activity of both the wind speed-treated group and the control fruit increased during storage (C in fig. 13), and at 0-20 d, there was no significant difference in POD activity between the CK and wind speed-treated groups, and after 20d storage, the POD activity of the wind speed-treated group was significantly higher than that of the CK group (p < 0.05). The SOD activity of both the anemometric group and the control fruits rose sharply within 20 days of storage and then declined gradually. Wind speed treatment maintained significantly higher SOD activity (P <0.05) throughout storage compared to control (D in figure 13). GLU activity showed the same trend as PAL activity, with an increasing trend for each treatment during the 40 day storage period (FIG. 13, panel E). The wind speed treated group CHI enzyme activity was significantly improved after 10d storage (P <0.05) compared to the control treatment, with the wind speed treated group CHI values up to 35.82% at 20d (FIG. 13F) which is 1.74 times higher than the control group.

Various non-biological technologies and biological agents induce fruits and vegetables to generate defense resistance, which is a common method for controlling postharvest diseases of fruits and vegetables. SOD, POD, CAT and PAL are defense enzymes closely related to the post-harvest disease resistance of plants. Antioxidases such as superoxide dismutase (SOD), Peroxidase (POD), Catalase (CAT) and the like play important roles in eliminating active oxygen, reducing membrane lipid peroxidation level, improving plant stress resistance and the like. SOD is a natural free radical scavenger in the body, which can catalyze O₂ ^-To produce H, thereby producing H₂O₂And O₂. POD is an important defense enzyme in a phenylpropane metabolic pathway, is closely related to plant disease resistance, and contributes to catalyzing the production of lignin and improving the stability of a cell structure. The flow phase wind velocity treatment obviously improves grape POD activity (P)<0.05) (C in fig. 13), suggesting that wind speed treatment may reduce oxidative stress during fruit fungal infection. In the early stage of treatment, for removing O₂ ^-The SOD activity of the plants is increased, and the SOD activity is gradually reduced in the later period of treatment. This decline may be due to the coordination of its own enzyme system. CAT activity decreased during the late storage period. This may be associated with a persistent resistance response of the grapes. After the grapes are treated by the flowing-phase wind speed, antioxidant enzymes (POD, SOD and CAT) are increased, which indicates that the wind speed treatment can improve the disease resistance of the grapes. CAT by passing H₂O₂Is eliminated as H₂O and O₂To alleviate H₂O₂Toxicity to plant tissues. PAL is one of the key enzymes for synthesizing phenolic compounds through a phenylpropyl pathway, and plays an important role in enhancing the defense resistance of plants in the experiment, the activities of CAT enzyme and PAL enzyme are improved by the flowing-phase wind speed treatment. Plants have many mechanisms to protect against pathogens. CH (CH)I and GLU are part of the plant's defense mechanism against pathogen invasion, and they can damage the fungal cell wall, poison the cell wall or cause loss of function. GLU stimulates host defense responses by releasing beta-13 glucan and chitosan oligosaccharides. We found that wind speed treatment significantly improved the CHI and GLU activities of fresh grapes, and that wind speed treatment at low temperature conditions improved the disease resistance of grapes, which may be related to the inhibition of wind speed on the growth of pathogenic bacteria. In a word, the flowing phase wind speed treatment can effectively inhibit the growth of botrytis cinerea and induce and change the activities of CAT, PAL, POD, SOD, GIU and CHI enzymes of grapes.

5.2 grape SO₂Intermittent fluid phase fumigating and removing antiseptic fresh-keeping

The sub-warehouse internal circulation ventilation system, as shown in FIG. 7, comprises upper and lower ventilation openings, back aluminum foil coiled pipe or PVC pipe (FT) connected by flange, axial flow fan installed in the upper hole, and air volume 30-40 times (7000-³H). Wherein the lower hole is a circular sealing window with the diameter of 400mm and is opened into the sub-warehouse. And preserving the fluid phase in the storage period. The inner circulation of the flow phase wind speed runs for 2h each day.

The working principle and the application effect of the gas intermittent fumigation-off equipment matched with the phase temperature warehouse are shown in figure 14. SO of gas intermittent fumigation equipment 21₂The air inlet pipe 22 is inserted into the sub-reservoir and is uniformly divided into a plurality of branch air inlet pipes 26 in the sub-reservoir, so that the uniformity of air inlet is ensured. A plurality of exhaust holes 24 are formed at the top of the sub-warehouse, each exhaust hole is connected with a branch exhaust pipe 25, and the branch exhaust pipes are connected with an SO₂Exhaust manifold 23, SO₂Gas intermittent fumigating and removing equipment connected with exhaust main pipe

The technical bottleneck of grape fresh-keeping is the rot caused by mould infection, mainly gray mold and downy mildew, the traditional technology uses sulfite powder or tablets, and SO is released by deliquescence₂Strong oxidation sterilization, but the fruit is easy to generate SO₂The pesticide damage bleaching and the residual quantity is large. Red globe grape pair SO₂The invention adopts a fluid phase intermittent fumigation technology, namely SO for the first time₂Circulating fumigation with concentration of 10000ppm for 30min, then removing completely, circulating fumigation with concentration of 2000ppm for 30min every 15 days, and synchronously starting fluid phase anticorrosion equipment in the fumigation process. The technique can maintain titratable acidThe content and the integrity of cell membranes are kept, the red globe grape is stored for 180 days, the rotting rate is only 3.9 percent, the bleaching index is 0.3, the residual quantity of sulfur dioxide is 3.1mg/kg and is lower than the limited quantity of FDA, and the storage effect is good. The pulse type preservation is obviously superior to the traditional tablet soaking type treatment, and in the storage period of 180 days, the pulse type preservation technology is adopted, SO that the fruits are actually contacted with SO₂The cumulative time of (a) is only 6-7 hours. The technology depends on the accurate quantitative timing control of the pulse type anticorrosion equipment, can be commercially popularized, and has very wide market prospect.

(1) Different SO₂Influence of pulse antiseptic conditions on storage titratable acid content of red globe grapes

SO₂The concentration affects the titratable acid content of the fruit. As shown in FIG. 15, the titratable acid trend downward during the storage period of red globe grapes. On day 180, the titratable acid content of the control group was 0.15%, while the 1000ppm pulse treatment, the first 10000ppm treatment and the first 2000ppm treatment were 0.18%, 0.25%, 0.22%, respectively. Are all obviously superior to the control group, which shows that the SO₂Compared with the traditional preservative tablet treatment, the pulse preservative treatment can effectively inhibit the drop of the titratable acid value. Different pulse treatment groups are firstly treated by 10000ppm, and the rest treatment groups with the interval of 15 days of 2000ppm can effectively inhibit the consumption of titratable acid after grape harvesting.

(2) Different SO₂Effect of pulsed Corrosion protection conditions on the relative conductivity of stored Red globe grapes

The relative conductivity can reflect the external SO of the grape fruits and vegetables₂And the like under the stress of severe environment, and mainly shows that the conductivity is increased. As can be seen from fig. 16, the relative conductivity values of the treatment groups all increased, wherein the control group and the 2000ppm120min cyclic fumigation treatment group increased faster, and the relative conductivities of the CK group, TR1 group, TR2 group and TR3 group were 52%, 49%, 39% and 41%, respectively, at the end of storage. The results show that the grapes treated by the preservative paper are soaked in low-concentration SO for a long time₂In the environment, SO₂Peroxidation on cell membranes and certain damage to the cell membranes, and 1000ppm SO₂The fumigation treatment is carried out for 120min each time, and the relative conductivity value of the film is higher than 30min for antiseptic treatment due to overlong fumigation time. TR2 group and TR3 groupThe relative conductivity of the compounds has no significant difference (P is less than 0.05) and is lower than that of a control group and TR1, which indicates that the antiseptic is finished and SO is rapidly removed₂Has important function for reducing membrane damage.

(3) Different SO₂Influence of pulse antiseptic condition on red globe grape storage weight loss rate and rotting rate

The main problems of weight loss, rot, falling particles and bleaching are the preservation of the grapes. As shown in Table 1, the red globe grape is stored for 180 days, and the control group antistaling agent slowly releases SO for a long time₂Soaking type fresh-keeping, the falling grain rate is up to 16.5%, the bleaching index is up to 10.8, SO₂The best pulse type antiseptic treatment group is TR2, the weight loss rate is only 3 percent, the decay rate is 3.9 percent, the falling rate is 5.1 percent, the bleaching index is 0.3, the TR1 treatment group has the lowest decay rate but higher bleaching index due to overlong pulse fumigation time, and the decay rate of the TR3 treatment group is higher than that of TR2, which indicates that the first high-concentration SO after grape harvest₂Preservation plays an important role.

TABLE 1 weight loss, rotting, threshing and bleaching index for 180 days storage of red globe grapes from different treatment groups

Data are presented as mean ± standard deviation, with no significant difference (P <0.05) indicated by alphabetical identity between each row of treatments.

(4) Different SO₂Effect of pulsed Corrosion protection conditions on the Activity of PPO in storage of Red globe grapes

The sulfite preservative can cause the PPO activity of the litchi to be increased. From figure 17, the PPO activity of the red globe grapes is in a trend of rising first and then falling in the storage process, the PPO activity of the red globe grapes is 13.2U/g and falls fastest probably due to SO when the red globe grapes are stored for 90 days, and the change degree is maximum when the red globe grapes are treated by 1000ppm cyclic fumigation for 120min₂The enzymatic defense system of the red globe grapes is damaged by long-time fumigation, and the polyphenol oxidase activity can be well maintained by firstly fumigating 10000ppm and the rest fumigating 2000ppm and then quickly removing the treatment groups.

(5) Different SO₂Pulse corrosion-proof condition pairEffect on storage POD Activity of Red globe grape

Grape tolerance to SO₂The mechanism is related to the magnitude of change in POD activity. The PPO activity of the red globe grapes shows a trend of rising first and then falling in the storage process, the POD activity of the CK group and the TR2 group is remarkably superior to that of other treatment groups when the CK group and the TR2 group keep POD activity at the 180 th day of the storage period, and the POD activity is 12.1U/g, and the graph is shown in FIG. 18.

(6) Different SO₂Effect of pulsed Corrosion protection conditions on storage of Vitis vinifera Malondialdehyde (MDA)

From figure 19, in the storage process, the rising speed of the malondialdehyde content of the CK group and the TR1 treatment group is higher than that of the TR2 and TR3 treatment group, the pulse type cyclic fumigation is carried out for 30min, and then SO is rapidly removed₂Can inhibit the increase of malondialdehyde content in the storage period of grape, and maintain the integrity of grape cell membrane.

(7) Different SO₂Pulse antiseptic condition for red globe grape pulp SO₂Influence of residual amount

From FIG. 20, SO in pulp with prolonged storage time₂The residual quantity is in an ascending trend, when the compound is stored for 180 days, the residual quantity of CK group reaches 13mg/kg, which exceeds the American FDA standard (10mg/kg), TR2 group SO₂The residual amount is only 3.1mg/kg, and the TR2 and TR3 groups have SO in the storage period₂The residue has no significant difference (P is less than 0.05), which indicates that the pulse type antisepsis is carried out for 30min and is rapidly removed, and the removal is carried out after 120min compared with the antisepsis and the SO with low concentration₂The long-time soaking (CK group) of the preservative can obviously reduce the storage period SO₂And (4) residual quantity.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various changes and modifications can be made without departing from the inventive concept, and these changes and modifications are all within the scope of the present invention.

Claims

1. A grape fluid phase antiseptic fresh-keeping method is characterized in that: the method comprises the following steps:

(1) regulating and controlling quality before mining;

(2) harvesting without injury;

(3) precooling the tunnel in a high-humidity differential pressure manner;

2. The preservation method according to claim 1, characterized in that: the pre-harvest quality regulation and control comprises the steps of spraying a quality inducer on the surfaces of leaf surfaces and fruits within 15 days before harvest, wherein the quality inducer consists of a component A and a component B, the component A is sprayed firstly, the component B is sprayed every other day, the components are diluted by 300 times and are sprayed for 1-3 times respectively;

3. The preservation method according to claim 1, characterized in that: the non-injury harvesting is carried out through a non-injury turnover box, the storage bin body structure of the non-injury turnover box is arc-shaped, a drain hole is formed in the middle bottom of the storage bin, five layers of composite fresh-keeping pads are arranged on the inner surface of the storage bin, each storage bin comprises a blocking layer, an application layer, a drug-carrying layer, an adsorption layer and an anti-fog layer which are sequentially arranged, and all the layers are combined together in a bonding mode.

4. The preservation method according to claim 3, characterized in that: the barrier layer is made of non-woven fabrics, the pesticide application layer is a microencapsulated plant essential oil preservative, the pesticide carrying layer is one of a polypropylene film or a polyethylene film, the adsorption layer is composed of 5-8 wt% of 1-methylcyclopropene, 94-91 wt% of potassium permanganate and 1 wt% of polyacrylate, and the antifogging layer is made of laminating paper.

5. The preservation method according to claim 3, characterized in that: the wall-core ratio of the microencapsulated plant essential oil preservative is 4: 1, and the core material is clove essential oil: the cinnamon essential oil is composed of wall materials of 50 wt% of beta-cyclodextrin, 40 wt% of chitosan and 10 wt% of tween 80 according to the volume ratio of 1: 1.

6. The preservation method according to claim 3, characterized in that: the box wall of the turnover box is of a sandwich structure, the side wall of the turnover box is provided with an openable vent hole, and the interlayer is internally provided with a coolant according to actual needs.

7. The preservation method according to claim 1, characterized in that: the simple and easy high wet differential pressure precooling in tunnel be in the freezer, with naked grape fruit basket dress pile-up on the tray, the tray is put in static pressure case trompil one side, hugs closely the static pressure case, aligns in proper order and discharges, hides tight with the side above the goods heap with PVC cloth, and when the fan rotated, at the negative pressure incasement production negative pressure, the cold air in the suction freezer, the cold air crosses the flow entering static pressure case from the goods heap afterbody, two axial fan of static pressure case top installation, the positive trompil of static pressure case, the humidifier is installed to the static pressure incasement.

8. The preservation method according to claim 7, characterized in that: and in the pre-cooling process, 1 mu L/L1-MCP is used for treatment at the same time, and the treatment time is 12 h.

9. The preservation method according to claim 1, characterized in that: the phase temperature storehouse flow phase anticorrosion storage is that the grapes are placed in a phase temperature storehouse, the phase temperature storehouse is of a primary and secondary jacket structure, an evaporator is installed on the primary storehouse, cold air blown out by the evaporator transmits cold energy into a secondary storehouse through an aluminum plate of the secondary storehouse, the secondary storehouse is airtight, a flow phase anticorrosion system is installed on the secondary storehouse, and flow phase wind speed processing is adopted.

10. The preservation method according to claim 1, characterized in that: the SO₂Intermittent fluid phase fumigating for removing primary SO₂Circulating fumigation with concentration of 10000ppm for 30min, then circulating fumigation with 2000ppm for 30min every 15 days, and synchronously starting fluid phase anticorrosion equipment in the fumigation process.