TECHNICAL FIELD

The disclosure belongs to the field of fruit and vegetable preservation, and particularly relates to a fruit and vegetable phase-temperature precooling compatible multi-coupling anti-aging treatment technology and device.

BACKGROUD OF THE PRESENT INVENTION

Preservation of fruits and vegetables is based on post-harvest physiology and pathology and with temperatures, humidity, gases and anticorrosion as means, wherein activity ratio of temperature is about 60%-70%, humidity, gases and anticorrosion each accounts for 10%-15%. Thus, under the condition that cold damage or freeze injury is not generated, the lower the preservation temperature of fruits and vegetables is, the better the preservation effects are. The precooling for removal of field heat as soon as possible is defined as a first 1 km in cold chain. A technology that a refrigeration house invented by an engineer James from Australia in 1851 is used for storing fruits and vegetables is considered as a first revolution, a controlled atmosphere cold storage invented by Kidd and West from University of Cambridge in 1927 is considered as a second revolution, and some people say that a subatmospheric pressure storage technology proposed by Bouguer in 1962 or an ice temperature warehouse storage technology proposed by Yamane Akimi from Japan in 1972 is considered as a third revolution.

The refrigeration house is subjected to temperature reduction and constant temperature depending on mechanical refrigeration, with temperature difference being ±0.5-1° C.; for the CA cold storage, concentrations of oxygen and carbon dioxide gases under the storage temperature are regulated at random on the basis of the refrigeration house; the ice temperature warehouse has the same principle as the refrigeration house, but temperature control precision is ±1° C. higher than that of a reduced pressure technology, however, the common defect of the refrigeration house, the controlled atmosphere cold storage, a reduced pressure house and the ice temperature warehouse technologies is heat and mass transfer. When in operation, a humidifier is continuously used for humidifying, and meanwhile an air cooler continuously performs defrosting.

Lingwu long jujube is a good fresh fruit variety having local features in Ningxia Hui Nationality Autonomous, China. Its fruit is colorful in color, thick in pulp, sour and sweet, delicious, rich in multivitamins and minerals, especially, has the highest VC content, is honored as live “vitamin pill”, and has a reputation of “king of fruits”. Heat carried by Lingwu long jujube after being harvested is large, a high temperature can increase respiration intensity of the Lingwu long jujube so as to finally lead to aging and deterioration. Precooling aims to maintain the quality of Lingwu long jujube and is one of important means to extend a shelf life. Through precooling, the loss of the product can be reduced, energy is saved. However, the traditional refrigeration house is large in house size and has a high requirement on quantity of fruits and vegetables. Furthermore, when a lot of fruits and vegetables are simultaneously precooled, the precooling efficiency is low, precooling time consumption is long, and energy consumption is large.

Precooling is incapable of preventing corrosion and mold; under the closed environment, temperature reduction cannot be performed; during the precooling for 10 hours, golden treatment time is within 10 hours, anticorrosion and mold prevention are simultaneously completed, and precooling, anticorrosion, mold prevention and anti-aging processes are completed within the golden time.

The existing technology has the disadvantages that:

1. Most of the existing refrigeration houses performs static precooling, which is slow in heat and mass transfer, low in cold capacity utilization rate and long in precooling time consumption, and easily causes water loss. 2. Most of fruit and vegetable treatment manners are that fruits and vegetables are precooled and then subjected to preservative treatment, in such a way, the optimal preservation time of fruits and vegetables are easily missed. 3. The traditional tunnel differential pressure precooling has only one temperature reducing manner, and thus cannot select a specific temperature reducing manner directed to the variety of fruits and vegetables, for example, the Lingwu long jujube easily generates a purupuru disease due to adoption of a rapid temperature reduction manner under the high-temperature and high-humidity environment. 4. In the prior art, a preservative cannot be added in the precooling, and addition of no preservative while precooling is result from heat and mass transfer so that the preservative cannot functions; 1-MCP is contained, which is toxic to human; in the present application, each space is an airtight independent space, and unit operation is carried out. 5. The first defect of the traditional precooling technology is heat and mass transfer; fruit and vegetable precooling technologies such as refrigeration house static precooling, differential pressure tunnel air precooling, cold water precooling and vacuum precooling have the common features that fruits and vegetables continuously loss water while precooling and reducing temperature; in the process of precooling, the larger lost water amount is, the rapid the temperature reducing and water losing speed is. 6. The second defect of the traditional precooling technology is that environment development cannot be compatible with precooling and disease-resistant anti-aging treatment. Based on the above first defect of precooling heat and mass transfer, in the process of precooling fruits and vegetables, even though a totally closed box type process technology is adopted, the air cooler of a refrigerating system adsorbs water, a physiological regulator, a preservative and the like of an environment phase while strengthening heat exchange so that precooling of fruits and vegetables cannot be compatible with disease-resistant anti-aging treatment, that is to say, because temperature reduction is carried out in advance, the optimal disease-resistant anti-aging time has to be sacrificed, for example, the optimal treatment time of an ethylene antagonist 1-MCP (1-methyl cyclopropene) is within 24 after harvest, while the optimal precooling time of fruits and vegetables is also within 24 hours after harvest, and therefore a manner that precooling is performed and then 1-MCP treatment is adopted has to be adopted. 7. The third defect of the traditional precooling technology is that controlled atmosphere, pressure reduction and precise ice temperature control can not be collaborative, that is to say, the precise temperature control of large exchanged heat cannot be met while controlled atmosphere and pressure reduction.

According to retrieval, patent documents related to the present application particularly disclose the following contents and comparison analysis is as follows:

1. Compared with Chinese Patent No. CN105794953A, entitled with differential pressure precooling system and method, which mainly describes that a differential pressure precooling system and method can rapidly cool fruits and vegetables while supplementing water lost from fruit and vegetable agricultural products in the process of reducing the temperature, so as to improve the preservation rate of fruit and vegetable agricultural products. The existing problem is that fruits and vegetables cannot undergo preservative treatment while precooling.

2. Compared with Chinese Utility Model No. CN205174974U, entitled with a tunnel type differential pressure precooling device for kiwi fruits, which solves the defects that the traditional precooling house and forced ripening house have single functions, achieves a fact that preccoling and forced ripening are simultaneously performed in one house, sufficiently utilizes space and time used by the house and reduces building cost. The existing problem is that there is no stifling box, the function is single, forced ripening is only performed, and an airtight and inner circulating state cannot be built.

3. Compared with Chinese Utility Model No. CN204132285U, entitled with a mini differential pressure type rapid precooling and air stifling device, which can simultaneously control gases and humidity, is simple in structure and convenient to operate, a fruit and vegetable storage chamber is adjustable in capacity. The existing problem is that although a problem of precooling and forced ripening is solved, precooling can not be performed as to the variety of fruits and vegetables, and fruit and vegetable precooling diseases are easily generated.

In order to solve the above problems, the present application provides a set of new precooling systems, thereby perfectly solving the above problems.

SUMMARY OF PRESENT INVENTION

The objective of the disclosure is to overcome the disadvantages in the prior art and provide a technology and device for fruit and vegetable phase-temperature precooling compatible multi-coupling anti-aging treatment, which have the advantages of rapid precooling and convenient operation, and are suitable for precooling in a fruit garden if a preservative is added.

In order to solve the above technical problem, the technical solution adopted by the disclosure is as follows:

A device fruit and vegetable phase-temperature precooling compatible multi-coupling anti-aging treatment comprises a refrigeration house in which a plurality of differential pressure precooling devices are placed; the structure of the differential pressure precooling device comprises a hermetic seal tunnel precooling box, a separator plate is fixedly mounted at an upper part of the inside of the tunnel precooling box and is arranged in parallel to a top wall of the tunnel precooling box with a space formed between the separator plate and the top wall; the separator plate extends to the bottom of the tunnel precooling box; a venting plate is fixedly mounted to one side of the separator plate and is arranged in parallel to a side wall of the tunnel precooling box with a space formed between the venting plate and the side wall; a section of wind shield is vertically and downwardly mounted to an end of the other side of the separator plate; an axial flow fan is mounted at a corner of the tunnel precooling box, the corner is located between the separator plate and the venting plate; an air inlet of the axial flow fan corresponds to an upper space of the separator plate, and an air outlet corresponds to the space between the venting plate and the side wall of the tunnel precooling box; a plurality of fruit frames are arranged in the tunnel precooling box and located between the venting plate and the wind shield, and Lingwu long jujube fruit cases are stacked on the fruit frames; a plurality rows of vacuum heat exchange tubes are hermetically mounted on the separator plate, one ends of the vacuum heat exchange tubes are located in the tunnel precooling box, and the other ends are located in a refrigeration house; a low temperature of the refrigeration house is introduced into the tunnel precooling box to achieve rapid temperature reduction in the tunnel precooling box under airtight regulation; an ultrasonic nebulizer is mounted on the separator plate at one side close to an axial flow fan; the ultrasonic nebulizer is filled with preservative solution; in the process of cold air circulation, the fan circulates the preservative solution to each corner of the tunnel precooling box; an ozone generator and an ultraviolet sterilization device are arranged in a hermetic seal tunnel precooling box; the preservative comprises the following components: 1-3 parts of methyl jasmonate, 2-3 parts of Tecto® (thiabendazole), 2-3 parts of sodium hydrogen peroxide, 2-3 parts of salicylic acid and 0.5-1 part of 1-MCP.

Furthermore, a size of particles of the preservative solution sprayed out from the ultrasonic nebulizer ranges from 0.5 μm to 0.8 μm.

Furthermore, a length of the wind shield is ⅓ that of the venting plate.

Furthermore, the preservative is prepared by taking raw materials in parts by weight and dissolving the raw materials with water, wherein, the addition amount of water is 80-100 parts.

Furthermore, the tunnel precooling box is a plastic curtain or side walls of the tunnel precooling box are made ofinsulation plates.

The disclosure has the beneficial effects that:

1. According to the disclosure, heat exchange tubes are mounted on the upper part of the differential pressure precooling device, an axial flow type exhaust fan absorbs heat from cargoes, hot wind enters a venting pipeline, the heat exchange tubes exchange cold air in the refrigeration house with hot wind in the cargoes, thereby significantly improving precooling efficiency. In this disclosure, heat exchange tubes refer to heat pipes.

2. According to the disclosure, a preservative having a molecular intercalation and placeholder function is added in the cargoes while precooling to preserve cargoes while precooling, thereby obviously shortening storage pre-treatment time and improving the preservation length of cargoes.

3. According to the disclosure, a fact that the traditional differential pressure precooling device adopts a totally closed form is changed, heat but not mass is transferred via heat tubes so as to seal the preservative to prevent the volatilization of the preservative, thereby reducing loss of cargo water in the process of precooling, reducing cold capacity loss in the process of precooling and quickening precooling efficiency.

4. According to the disclosure, a totally closed form is adopted, loss of cargo water is reduced and is 2-3 times that of static precooling, cold capacity loss is reduced, addition of heat exchange tubes on the basis of the traditional tunnel differential pressure precooling device can significantly improve precooling efficiency which is improved by 3-5 times than that of static precooling, and improved by approximate 1 time than opened type differential pressure precooling. Addition of a preservative when in precooling can result in a fact that storage pretreatment time is shortened by 2 times, the preservation length of cargoes is extended by 1.5 times, and the preservation length of cargoes is significantly increased.

5. This device is in a totally closed state, a vacuum heat exchange tube is mounted at the upper end of the tunnel, the vacuum tube penetrates through the venting pipeline to extend into the tunnel, the axial flow type exhaust fan extracts hot air in the tunnel to pass through the heat exchange tube, the heat exchange tube exchanges cold air outside the tunnel with hot wind of cargoes in the tunnel to promote continuous reduction of temperature in the tunnel to form a closed internal circulating state, thereby obviously quickening precooling efficiency. The temperature is constant, humidifying is not performed, and energy consumption is saved.

6. According to the disclosure, the preservative is added in the precooling device while precooling, the preservative is added during the golden period of efficient heat transfer and precooling, preservative treatment is performed on precooled cargoes through internal circulation of the closed device so as to form a preservation effect on cargoes while precooling, thereby obviously shortening the storage pretreatment time and improving the preservation length of cargoes.

7. According to the disclosure, temperature can be rapidly reduced through precooling, and the temperature reducing speed of the device is targeted to be set aiming at different fruit and vegetable varieties.

8. Heat but not mass is transfer. A refrigerating system and a precooling and temperature reduction system are independent each other. The fruit and vegetable precooling system is airtight but does not preserve heat, wherein forced heat exchange when in temperature reduction is achieved depending on synergism of heat exchange tubes and forced convection of the axial flow fan.

9. Temperature reduction is compatible with disease resistance and aging resistance. The precooling temperature reduction system only has forced heat exchange without mutual exchange or transfer of media. Thus, within the first time after harvest, precooling is performed while an antagonist such as 1-MCP, a resistance inducer such as methyl jasmonate, a disease resistant agent such as calcium chloride, a bactericide such as sulfur dioxide, ozone, or physics such as static electricity and electric field and other preservation treatment is performed. The preservative can be either a gas or liquid nano atomizing gas.

10. Temperature reduction is synergic with controlled atmosphere, pressure reduction and precise ice temperature control. Precooling temperature reduction can regulate components of the gas at random like the controlled atmosphere cold storage at the same time and regulate the pressure like a pressure reduction house, and the temperature fluctuates ≤±0.1° C. like the ice temperature warehouse.

