阅读说明：本技术 甘薯储藏预处理设备及预处理方法 (Sweet potato storage pretreatment equipment and pretreatment method ) 是由 刘帮迪 冉国伟 孙洁 吕晓龙 沈剑波 孙静 程勤阳 周新群 于 2020-05-27 设计创作，主要内容包括：本发明涉及甘薯储藏技术领域,公开了一种甘薯储藏预处理设备及预处理方法,其中甘薯储藏预处理设备包括进出门相对设置的愈伤室和冷却室,所述愈伤室背离所述冷却室的一端连接有第一送风风机,所述第一送风风机的出口和所述愈伤室之间安装有加热装置；所述冷却室背离所述愈伤室的一端连接有第二送风风机。该甘薯储藏预处理设备通过对甘薯进行产后贮藏前的高温短时愈伤-冷却的预处理,以绿色无污染的物理方法,可有效加快甘薯块根愈伤组织的形成,缩短预处理时间,从而达到减少甘薯储期腐烂和水分损失,保证储藏品质,延长储藏期限的目的。(The invention relates to the technical field of sweet potato storage, and discloses sweet potato storage pretreatment equipment and a pretreatment method, wherein the sweet potato storage pretreatment equipment comprises a callus chamber and a cooling chamber, wherein the callus chamber and the cooling chamber are oppositely arranged by an access door; and one end of the cooling chamber, which deviates from the callus chamber, is connected with a second air supply fan. The sweet potato storage pretreatment equipment can effectively accelerate the formation of the callus of the tuberous roots of the sweet potatoes and shorten the pretreatment time by carrying out high-temperature short-time callus-cooling pretreatment on the sweet potatoes before postnatal storage by a green pollution-free physical method, thereby achieving the purposes of reducing the rot and water loss of the sweet potatoes in the storage period, ensuring the storage quality and prolonging the storage period.)

1. The sweet potato storage pretreatment equipment is characterized by comprising a callus chamber and a cooling chamber, wherein the callus chamber and the cooling chamber are oppositely arranged by an access door, one end of the callus chamber, which is far away from the cooling chamber, is connected with a first air supply fan, and a heating device is arranged between an outlet of the first air supply fan and the callus chamber; and one end of the cooling chamber, which deviates from the callus chamber, is connected with a second air supply fan.

2. The sweet potato storage pretreatment equipment as claimed in claim 1, wherein a return air duct is arranged above the callus chamber, an inlet of the return air duct is communicated with the inner chamber of the callus chamber, and an outlet of the return air duct is connected to an inlet of the first air supply fan; the lower part of the callus chamber is provided with a lower air supply duct, the inlet of the lower air supply duct is connected with the outlet of the heating device, and the outlet of the lower air supply duct is communicated with the inner cavity of the callus chamber.

3. The sweet potato storage pretreatment equipment of claim 2, wherein the top of the callus chamber is provided with a plurality of openable top windows in the length direction, and the inlet of the return air duct is communicated with the inner cavity of the callus chamber through the top windows.

4. The sweet potato storage pretreatment apparatus of claim 2, wherein the outlet of the heating device is connected to the inlet of the lower air supply duct and the air inlet of the callus chamber through a three-way regulating valve.

5. The sweet potato storage pretreatment apparatus of claim 1, further comprising a cleaning chamber disposed between the callus chamber and the cooling chamber, wherein a plurality of spray heads are installed in the cleaning chamber.

6. The sweet potato storage pretreatment apparatus according to claim 1, wherein a temperature sensor and a humidity sensor are installed in the callus chamber, and an electric air intake valve and a moisture exhaust fan electrically connected to the humidity sensor are further installed in the callus chamber.

7. The sweet potato storage pretreatment apparatus of claim 1, wherein a wet curtain is installed between the outlet of the second air supply fan and the cooling chamber.

8. The sweet potato storage pretreatment apparatus according to any one of claims 1 to 7, further comprising a slide rail and a loading trolley, wherein one end of the slide rail extends into the callus chamber and the other end of the slide rail extends into the cooling chamber; the loading trolley can slide along the slide rail.

9. A pretreatment method using the pretreatment apparatus for sweet potato storage according to any one of claims 1 to 8, comprising:

cleaning the sweet potatoes after being bagged;

conveying the cleaned sweet potato basket filled with the sweet potatoes into a callus chamber, wherein the temperature in the callus chamber is 60-65 ℃, the relative humidity is 20-30%, and the wind speed is at least 0.5m/s, and performing callus treatment for 20-40 min;

transferring the sweet potatoes after the callus treatment into a cooling chamber, wherein the temperature of the cooling chamber is 15-20 ℃, the relative humidity is 20-30%, and the wind speed is at least 0.5m/s, and carrying out cooling treatment;

and taking out the sweet potatoes for storage after the temperature of the sweet potatoes is reduced to below 18 ℃.

10. The pretreatment method according to claim 9, further comprising, before the cleaning of the basket-packed sweet potatoes:

cleaning the harvested fresh sweet potatoes, removing soil impurities on the surfaces of the fresh sweet potatoes, and removing the sweet potatoes with diseases and insect pests;

and respectively putting the selected sweet potatoes into sweet potato baskets, wherein the height of the sweet potato baskets is less than or equal to two thirds of the height of the sweet potato baskets.

Technical Field

The invention relates to the technical field of sweet potato storage, in particular to a sweet potato storage pretreatment device and a sweet potato storage pretreatment method.

Background

The sweet potato tuber has large volume, much water content, thin skin and tender meat, and is easily damaged by machines such as scratch, puncture, cut, bruise, pressure injury and the like in the processes of field harvesting, transportation, loading, unloading, warehousing and storage. In order to reduce the loss of the picked sweet potatoes and prevent the invasion of pathogens, the picked sweet potatoes are subjected to proper pretreatment, washed to remove soil-borne microorganisms on the surface, and stored after injury healing is promoted, so that the disease resistance of the sweet potatoes is improved, the storage period is prolonged, and the storage quality is ensured. The pretreatment methods adopted in the current production practice mainly comprise three methods, namely callus pretreatment, cleaning pretreatment and chemical agent pretreatment.

The callus pretreatment is mainly a traditional low-temperature heating callus pretreatment technology, sweet potatoes are usually selected and directly stacked in a storage facility for carrying out callus pretreatment, the temperature of the sweet potatoes is raised to 30-37 ℃ after the sweet potatoes are put in a warehouse, the treatment time is usually 2-7 days, and then the sweet potatoes are ventilated and cooled to enter a storage period. At present, no special equipment for callus pretreatment of sweet potatoes exists in the market and research, and the traditional low-temperature heating callus is usually carried out in a heating cold storage or a soil cellar.

The pretreatment of the chemical agent mainly comprises spraying the chemical agent to stimulate the callus, wherein the chemical agent treatment is generally that before storage, exogenous hormones such as Abscisic Acid (ABA), Benzothiadiazole (BTH) and Salicylic Acid (SA) are sprayed and soaked, and then the dried sweet potatoes are put in storage for storage, and the mode is mainly that the stimulation of the exogenous chemical agent is carried out on the sweet potatoes to promote the wound self-healing of the sweet potatoes in the storage process.

The cleaning pretreatment mainly comprises clear water cleaning or chemical agent cleaning, and mainly comprises the steps of cleaning the soil on the surface of the sweet potato by using clear water flushing cleaning, sodium hypochlorite solution flushing cleaning, lime spraying, pesticide soaking or spraying, bactericide flushing cleaning and the like, inactivating soil-borne microorganisms, draining, and warehousing for storage.

At present, the three main pretreatment methods all have some use defects, so that the storage effect of the sweet potatoes is poor. The low-temperature heating callus pretreatment period is long, the input of manpower and material resources is large, the conditions are difficult to control, the energy consumption is high, the callus effect is uneven, the cooling effect is not obvious, the final residual temperature of the sweet potatoes cannot be dissipated, the sweet potatoes are easy to rot in the storage period, and the production requirement cannot be met. The cleaning pretreatment and the chemical agent pretreatment relate to the problems of food safety and irregular use amount of chemical agents, the cost of exogenous hormone medicines is high, the sweet potato surface is wet easily due to spraying, soaking and other modes, the draining time is short, and the rotting in the storage period can be accelerated.

Disclosure of Invention

The embodiment of the invention provides a sweet potato storage pretreatment device and a pretreatment method, which are used for solving the problems that the existing sweet potato pretreatment has long treatment period and poor effect and cannot meet the production requirement.

The embodiment of the invention provides a sweet potato storage pretreatment device which comprises a callus chamber and a cooling chamber, wherein the callus chamber and the cooling chamber are oppositely arranged at an inlet and an outlet, one end of the callus chamber, which is far away from the cooling chamber, is connected with a first air supply fan, and a heating device is arranged between an outlet of the first air supply fan and the callus chamber; and one end of the cooling chamber, which deviates from the callus chamber, is connected with a second air supply fan.

The embodiment of the invention also provides a pretreatment method by using the sweet potato storage pretreatment equipment, which comprises the following steps:

cleaning the sweet potatoes after being bagged;

conveying the cleaned sweet potato basket filled with the sweet potatoes into a callus chamber, wherein the temperature in the callus chamber is 60-65 ℃, the relative humidity is 20-30%, and the wind speed is at least 0.5m/s, and performing callus treatment for 20-40 min;

transferring the sweet potatoes after the callus treatment into a cooling chamber, wherein the temperature of the cooling chamber is 15-20 ℃, the relative humidity is 20-30%, and the wind speed is at least 0.5m/s, and carrying out cooling treatment;

and taking out the sweet potatoes for storage after the temperature of the sweet potatoes is reduced to below 18 ℃.

The sweet potato storage pretreatment equipment and the pretreatment method provided by the embodiment of the invention have the advantages that the sweet potato storage pretreatment equipment carries out high-temperature short-time callus treatment on the sweet potatoes through the callus chamber, the injured pericarp of the sweet potatoes is quickly healed by utilizing a mode of thermally stimulating and regulating metabolic pathways and killing epidermal microorganisms at high temperature to form a biological barrier for resisting external disease microorganisms, the sweet potatoes after callus are quickly cooled by strong wind through the cooling chamber, the residual temperature of the sweet potatoes after callus is quickly reduced, the increase and loss of respiratory strength in the storage process are avoided, and the rotting condition in the early stage of storage is reduced. The sweet potato storage pretreatment equipment can effectively accelerate the formation of the callus of the tuberous roots of the sweet potatoes and shorten the pretreatment time by carrying out high-temperature short-time callus-cooling pretreatment on the sweet potatoes before postnatal storage by a green pollution-free physical method, thereby achieving the purposes of reducing the rot and water loss of the sweet potatoes in the storage period, ensuring the storage quality and prolonging the storage period.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and those skilled in the art can also obtain other drawings according to the drawings without creative efforts.

FIG. 1 is a schematic view showing the construction of a sweet potato storage pretreatment apparatus according to an embodiment of the present invention;

FIG. 2 is a plan view of the sweet potato storage pretreatment apparatus of FIG. 1;

FIG. 3 is a flow chart of a pretreatment process before sweet potato storage in the embodiment of the present invention;

FIG. 4 is a schematic view showing stacking of sweet potatoes in the same batch using a sweet potato storage pretreatment apparatus in an embodiment of the present invention, wherein a represents an upper sweet potato sample point, b represents a middle sweet potato sample point, and c represents a lower sweet potato sample point;

FIG. 5 is a graph showing the results of temperature monitoring changes of the temperature sensors in the callus chamber of the present invention;

FIG. 6 is a graph showing the results of humidity monitoring changes of humidity sensors in the callus chamber of the present invention;

FIG. 7 is a graph showing the temperature measurement results of the epidermis and the kernel of the same batch of sweet potatoes at different placing points after the callus treatment of the present invention;

FIG. 8 is a graph showing the temperature measurements of the outer skin and inner core of sweet potatoes in the same batch at different placement points after cooling treatment according to the present invention;

FIG. 9 is a graph of the results of the L value test after storage of example 1 and comparative examples 1 to 4;

FIG. 10 is a graph of the results of the a value test after storage of example 1 and comparative examples 1-4;

FIG. 11 is a graph of b-value test results of example 1 and comparative examples 1-4 after storage;

FIG. 12 is a graph showing the results of the browning test of sweet potatoes in example 1 and comparative examples 1 to 4 after storage;

FIG. 13 is a graph showing the results of the measurement of the respiration intensity of sweet potatoes in example 1 and comparative examples 1 to 4 after storage;

FIG. 14 is a graph showing the results of the internal hardness test of the sweet potato tissues after storage in example 1 and comparative examples 1 to 4;

FIG. 15 is a graph showing the results of the hardness test of the head and tail parts of sweet potatoes stored in example 1 and comparative examples 1 to 4;

FIG. 16 is a graph showing the results of the cell membrane permeability test of sweet potatoes stored in example 1 and comparative examples 1 to 4;

FIG. 17 is a graph showing the results of the malondialdehyde content test of sweet potatoes in example 1 and comparative examples 1 to 4 after storage;

FIG. 18 is a graph showing the results of a test of the incidence of cold damage of sweet potatoes stored in example 1 and comparative examples 1 to 4;

FIG. 19 is a graph showing the results of a test of rotting rate of sweet potatoes in example 1 and comparative examples 1 to 4 after storage;

FIG. 20 is a graph showing the results of weight loss rate tests of sweet potatoes in example 1 and comparative examples 1 to 4 after storage;

FIG. 21 is a graph showing the results of the starch content test of sweet potatoes in example 1 and comparative examples 1 to 4 after storage;

FIG. 22 is a graph showing the results of the soluble sugar content test of sweet potatoes in example 1 and comparative examples 1 to 4 after storage;

FIG. 23 is a graph showing the results of the ascorbic acid content test of sweet potatoes stored in example 1 and comparative examples 1 to 4.

Description of reference numerals:

1. a callus chamber; 2. A cooling chamber; 3. A first air supply fan;

4. a second air supply fan; 5. A main blast pipe; 6. A heating device;

7. an air return duct; 8. A lower air supply duct; 9. A top window;

10. a three-way regulating valve; 11. A front end temperature and humidity sensor; 12. A terminal temperature and humidity sensor;

13. an electric air inlet valve; 14. A moisture removal fan; 15. A slide rail;

16. sweet potato baskets; 17. An air outlet valve of the callus chamber; 18. An air outlet of the cooling chamber;

19. a wind scoop; 20. A cleaning chamber; 21. A shower head;

22. a water outlet; 23. A control box; 24. And (5) wet curtain.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the embodiments of the present invention, it should be noted that the terms "first" and "second" are used for clearly indicating the numbering of the product parts and do not represent any substantial difference unless explicitly stated or limited otherwise. The terms "upper", "lower", "left", "right", and the like are used only to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships may also be changed accordingly. Specific meanings of the above terms in the embodiments of the present invention can be understood by those of ordinary skill in the art according to specific situations.

It is to be understood that, unless otherwise expressly specified or limited, the term "coupled" is used broadly, and may, for example, refer to directly coupled devices or indirectly coupled devices through intervening media. Specific meanings of the above terms in the embodiments of the invention will be understood to those of ordinary skill in the art in specific cases.

As shown in figures 1 to 2, the sweet potato storage pretreatment equipment provided by the embodiment of the invention comprises a callus chamber 1 and a cooling chamber 2 which are oppositely arranged at an access door, wherein one end of the callus chamber 1, which is far away from the cooling chamber 2, is connected with a first air supply fan 3, and a heating device 6 is arranged between the outlet of the first air supply fan 3 and the callus chamber 1. One end of the cooling chamber 2 departing from the callus chamber 1 is connected with a second air supply fan 4.

Specifically, callus on the sole room 1 and the relative setting of cooling chamber 2, callus on the sole room 1 and cooling chamber 2 all can be an open-ended cavity box in both ends, and the size of box can be as required rational design. In a specific embodiment, the callus chamber 1 and the cooling chamber 2 have a volume of 12m³700 kg-800 kg of sweet potatoes can be processed at one time.

One end of the callus chamber 1 departing from the cooling chamber 2 is connected with the outlet of the first air supply fan 3 through an air hopper 19, a heating device 6 and a main air supply pipe 5 in sequence; one end of the callus chamber 1 facing the cooling chamber 2 is provided with a first opening and closing door. After the first access door is opened, the sweet potatoes to be treated can be put into the callus chamber 1, and the sweet potatoes after the callus treatment can also be moved out of the callus chamber 1. In addition, a callus chamber air outlet valve 17 can be further installed on the first access door, and the callus chamber air outlet valve 17 can be a manual air valve or an electric air valve. By opening the first air supply fan 3 and the air outlet valve 17 of the callus chamber (or directly opening the first access door), a tunnel type ventilation mode can be formed in the callus chamber 1. The first air supply fan 3 can adopt a centrifugal fan, and a frequency converter can be additionally arranged as required to adjust the air speed in the callus chamber 1. The heating device 6 may employ an electric heater, and more specifically, the electric heater may employ a PTC thermistor material as a heating element, while having an enhanced overload protection function.

One end of the cooling chamber 2, which is far away from the callus chamber 1, is connected to the outlet of the second air supply fan 4 through an air hopper 19 and an air supply pipe in sequence; the cooling chamber 2 is provided with a second openable and closable access door at one end facing the callus chamber 1. After the second access door is opened, the sweet potatoes after the callus treatment can be placed into the cooling chamber 2, and the sweet potatoes after the cooling treatment can also be moved out of the cooling chamber 2 and finally placed into a storage cellar or a cold storage for storage. In addition, a cooling chamber air outlet 18 can be further installed on the second access door, and the cooling chamber air outlet 18 can be a shutter air outlet or other air outlet structures. By opening the second air supply fan 4 and the cooling compartment air outlet 18 (or directly opening the second access door), a tunnel type ventilation mode can be formed in the cooling compartment 2. The second air supply fan 4 can adopt a centrifugal fan, and a frequency converter can be additionally arranged as required to adjust the air speed in the cooling chamber 2.

When the device is used, sweet potatoes can be firstly centralized and bagged in the area between the callus chamber 1 and the cooling chamber 2, the stacked sweet potatoes are orderly transferred to the callus chamber 1 to be callus, after the callus treatment is finished, the whole sweet potatoes are directly transferred from the callus chamber 1 to the cooling chamber 2 to be cooled, and the sweet potatoes can be unloaded from the area between the callus chamber 1 and the cooling chamber 2 after the cooling treatment is finished. In addition, the callus chamber 1 and the cooling chamber 2 can be continuously used at the same time, when the sweet potatoes in the previous batch are processed in the cooling chamber 2, the sweet potatoes in the next batch can be transferred into the callus chamber 1 for callus processing, and the overall processing speed is further improved.

The embodiment provides a sweet potato storage pre treatment equipment, carry out high temperature short-time callus on the earth through callus on the earth room 1 to the sweet potato, utilize the heat shock to adjust metabolic pathway and the mode of high temperature extermination epidermis microorganism, make the injured pericarp of sweet potato heal fast, form the biological barrier who resists outside disease microorganism, the rethread cooling chamber 2 carries out strong wind fast cooling to the sweet potato after healing, reduce the residual temperature of sweet potato after healing fast, avoid promotion and the loss of respiratory intensity among the storage process, reduce the rotten condition of early stage of storage. The sweet potato storage pretreatment equipment can effectively accelerate the formation of the callus of the tuberous roots of the sweet potatoes and shorten the pretreatment time by carrying out high-temperature short-time callus-cooling pretreatment on the sweet potatoes before postnatal storage by a green pollution-free physical method, thereby achieving the purposes of reducing the rot and water loss of the sweet potatoes in the storage period, ensuring the storage quality and prolonging the storage period.

Further, as shown in fig. 1 and fig. 2, it also includes a slide rail 15 and a loading trolley (not shown in the figure), one end of the slide rail 15 extends into the callus chamber 1, and the other end of the slide rail 15 extends into the cooling chamber 2. The loading trolley can slide along the slide rails 15. In particular, the loading trolley can be an electric flat car or a trolley, and the sweet potatoes can be easily and effortlessly translated between the callus chamber 1 and the cooling chamber 2 through the loading trolley. The loading trolley can be loaded with a plurality of sweet potato baskets 16 made of plastic materials.

Furthermore, as shown in fig. 1, a return air duct 7 is arranged above the callus chamber 1, an inlet of the return air duct 7 is communicated with an inner chamber of the callus chamber 1, and an outlet of the return air duct 7 is connected to an inlet of the first air supply fan 3. A lower air supply duct 8 is arranged below the callus chamber 1, the inlet of the lower air supply duct 8 is connected with the outlet of the heating device 6, and the outlet of the lower air supply duct 8 is communicated with the inner chamber of the callus chamber 1. Through the arrangement of the lower air supply duct 8 and the air return duct 7, hot air can pass through the inner cavity of the callus chamber 1 from bottom to top, and a box type ventilation mode is formed.

Furthermore, as shown in fig. 1 and 2, the top of the callus chamber 1 is provided with a plurality of openable top windows 9 in the length direction, and the inlet of the return air duct 7 is communicated with the inner chamber of the callus chamber 1 through the top windows 9. The top window 9 can adopt a manual push window or an electric push window. The return air duct 7 may be provided with a plurality of inlets, each inlet being provided in one-to-one correspondence with the roof window 9. The lower air supply duct 8 can also be provided with a plurality of outlets along the length direction of the callus chamber 1, so that uniform air outlet is ensured.

Furthermore, as shown in FIG. 1, the outlet of the heating device 6 is connected to the inlet of the lower air supply duct 8 and the air inlet of the callus chamber 1 through a three-way regulating valve 10. Specifically, the valve body of three-way regulating valve 10 can be directly with 19 integrated designs of wind scoop, lower air supply duct 8 locate in 19 wind scoop and form the junction at 19 neck of wind scoop, three-way regulating valve 10 still sets up the valve plate at the junction including rotating, and the pivot of valve plate can extend to 19 outer formation handles of wind scoop, also can lug connection in the motor, realizes automatically controlled.

The inlet of the lower air supply duct 8 can be completely shielded by rotating the valve plate, and at the moment, the air outlet of the first air supply fan 3 completely enters the inner chamber from the air inlet of the callus chamber 1 to form tunnel type ventilation; or the valve plate completely shields the air inlet of the callus chamber 1, at the moment, the air outlet of the first air supply fan 3 completely enters the inner chamber from the lower air supply duct 8, and the top window 9 can also be opened in a linkage manner (or manually opened independently) with the three-way regulating valve 10, so that box type ventilation is formed; or the valve plate can be kept at the middle position, so that the outlet air can enter the inner chamber of the callus chamber 1 from the air inlet of the callus chamber 1 and the lower air supply duct 8 at the same time, and tunnel type and box type synchronous ventilation is formed. Generally, when the sweet potato treatment capacity is small, the sweet potato can be independently put into a tunnel type for ventilation; when the sweet potato treatment capacity is large, the sweet potato can be independently put into a box type for ventilation, hot air can be recycled through the box type ventilation, the improvement of the heat utilization rate is facilitated, and energy is saved.

Further, as shown in fig. 1 and 2, the device also comprises a cleaning chamber 20 arranged between the callus chamber 1 and the cooling chamber 2, and a plurality of spray heads 21 are arranged in the cleaning chamber 20. The sweet potatoes loaded in the sweet potato basket 16 can be washed by clean water through the spray header 21, so that large soil on the surfaces of all the sweet potatoes can be washed. The bottom of the washing chamber 20 is further provided with a water outlet 22, and the sewage accumulated in the washing chamber 20 is discharged in time through the water outlet 22, so that the sewage can be collected and treated in a centralized manner.

Further, as shown in fig. 1, a temperature sensor and a humidity sensor are installed in the callus chamber 1, and an electric air inlet valve 13 and a moisture exhaust fan 14 connected with a control box 23 are also installed in the callus chamber 1. Specifically, the front, middle and end, upper and lower, and left and right sides of the callus chamber 1 may be provided with temperature sensors and humidity sensors as needed. In a specific embodiment, the front section of the callus chamber 1 is provided with a front end temperature and humidity sensor 11, and the tail section is provided with a tail end temperature and humidity sensor 12. The temperature sensor, the humidity sensor, the first air supply fan 3, the heating device 6, the electric air inlet valve 13 and the dehumidifying fan 14 are all electrically connected with a control box 23 arranged outside the callus chamber 1. When the humidity of the callus chamber 1 is higher than the set humidity, the humidity sensor collects data to the control box 23, the control box 23 sends an instruction to open the electric air inlet valve 13 and the dehumidifying fan 14 after judging, external air enters the callus chamber through the electric air inlet valve 13, and indoor humid air is discharged out of the callus chamber 1 through the dehumidifying fan 14; when the humidity of the callus chamber 1 is lower than or equal to the set humidity, the electric air inlet valve 13 and the moisture exhaust fan 14 are stopped. The temperature and the humidity in the callus chamber 1 are controlled to be kept suitable by a temperature sensor and a humidity sensor. Further, as shown in fig. 1, a wet curtain 24 is installed between the outlet of the second blower fan 4 and the cooling compartment 2. In particular, the wet curtain 24 may be mounted within the wind scoop 19. The wet curtain 24 can provide cold for the cooling chamber 2, and when the air supply of the second air supply fan 4 passes through the wet curtain 24, a large amount of moisture is evaporated, so that the air supply temperature is reduced, and then the air supply temperature enters the cooling chamber 2, so that the indoor temperature is rapidly reduced. The sweet potatoes are generally harvested and stored in autumn in the north, the environmental temperature is lower at the moment and is about 15-20 ℃, and the sweet potatoes are cooled by wind at the environmental temperature. If the device is to be put into use in the south or summer, it is contemplated that the wet curtain 24 may be added or put into use.

Furthermore, the outside of the callus chamber 1 and the cooling chamber 2 is provided with a heat preservation layer, and the heat preservation layer is composed of a color steel plate, a heat preservation benzene plate and a snowflake plate lining in sequence from outside to inside.

As shown in fig. 3, the embodiment of the present invention further provides a pretreatment method using the pretreatment apparatus for sweet potato storage as described above, comprising:

step S300: cleaning the sweet potatoes after the basket is filled. Specifically, the cleaning may be performed directly in the cleaning chamber 20, or may be performed manually outside the apparatus.

Step S400: the cleaned sweet potato basket filled with the sweet potatoes is sent into a callus chamber 1, the temperature in the callus chamber 1 is 60-65 ℃, the relative humidity is 20-30%, and the wind speed is at least 0.5m/s, and the callus treatment is carried out for 20-40 min.

Step S500: transferring the sweet potatoes after the callus treatment into a cooling chamber 2, wherein the temperature of the cooling chamber 2 is 15-20 ℃, the relative humidity is 20-30%, and the wind speed is at least 0.5m/s, and carrying out cooling treatment;

step S600: and taking out the sweet potatoes for storage after the temperature of the sweet potatoes is reduced to below 18 ℃.

Further, before step S300, the method further includes:

step S100: cleaning the harvested fresh sweet potatoes, removing soil impurities on the surfaces of the fresh sweet potatoes, and removing the sweet potatoes with diseases and insect pests.

Step S200: the sweet potatoes after selection are respectively put into sweet potato baskets 16, the height of the sweet potato baskets is less than or equal to two thirds of the height of the sweet potato baskets 16, and the sweet potatoes are placed in a cool and ventilated place for treatment after the sweet potato baskets are filled.

This is described below in connection with a specific embodiment.

The variety of sweet potato tuber used in this example was sweet potato red-heart 'Niyan potato 25', produced from sweet eastern water. The embodiment provides a method for pretreating a sweet potato with a damage, which comprises the following steps:

step S100, selecting: the harvested fresh sweet potatoes (containing damaged sweet potatoes) are cleaned of soil impurities on the surfaces of the tuberous roots of the sweet potatoes, and the sweet potatoes with diseases and insect pests are removed.

Step S200, basket loading: sweet potatoes of different specifications are respectively put into sweet potato baskets 16 (the length is multiplied by the width is multiplied by the height is multiplied by 510mm multiplied by 320mm multiplied by 155mm), as shown in figure 4, the sweet potato baskets are not higher than two thirds of the position (the scale mark position in figure 4) in the sweet potato basket 16, twelve sweet potatoes are stacked together in each batch of sweet potato processing, and the sweet potatoes are placed in a cool and ventilated place for processing after being bagged.

Step S300, cleaning: washing the sweet potatoes after being bagged by clear water, so that large soil on the surfaces of all the sweet potatoes is washed away; the washing can be carried out manually outside the equipment, or the sweet potato baskets 16 filled with sweet potatoes can be directly stacked in two rows (as shown in figure 4) horizontally and vertically, placed on the loading trolley of the sweet potato storage pretreatment equipment, and pushed into the cleaning chamber 20 for automatic cleaning.

Step S400, high-temperature short-time callus pretreatment: the site of treatment for this experiment was at the pilot test site of the eastern water, 10 and 20 months in 2019, and the local temperature was 15.5 ℃. And (3) opening the heating device 6 for preheating in the first half hour of treatment, and simultaneously starting the first air supply fan 3 and the second air supply fan 4 to adjust the air speed. Then the loading trolley loaded with sweet potatoes is sent into the callus chamber 1 through a slide rail 15, and the sweet potatoes are placed in the constant-temperature constant-humidity callus chamber 1 with the temperature of 60-65 ℃, the relative humidity of 20-30% and the wind speed of 0.5m/s for heat shock treatment for 25 min.

Step S500, cooling pretreatment: the callus sweet potatoes are continuously placed on a small trolley and then enter a cooling chamber 2 rapidly cooled by strong wind along with a slide rail 15, the temperature is the ambient temperature, the relative humidity is 20-30%, and the wind speed is 1m/s, and the sweet potatoes are cooled for 10 min.

Step S600, storage: after the temperature of the sweet potato root tuber is reduced to below 18 ℃, the sweet potato root tuber is placed in a storage cellar or a cold storage with the temperature of 13 +/-1 ℃ and the relative humidity of 80-90 percent for storage.

Device performance verification: the stability of the equipment and the uniformity of the sweet potatoes after pretreatment in the process of healing and cooling the sweet potato storage pretreatment equipment of the embodiment are described by testing the temperature and humidity parameters of the equipment in the process of healing and cooling the sweet potatoes after selection, basket loading and cleaning in the sweet potato storage pretreatment equipment of the embodiment.

(1) Selecting and basketing: fresh sweet potatoes which are regular in appearance, uniform in size (weight of 200-300 g), free of damage and diseases and insect pests are selected from the field, collected in the sweet potato Siheshui, and then are bagged according to the method shown in figure 4 to wait for equipment pretreatment.

(2) High-temperature short-time callus-strong wind cooling pretreatment: sweet potatoes are pretreated according to the pretreatment mode of the embodiment.

(3) Collecting equipment data: in the actual operation process of the device, the temperature and humidity data collected by the temperature and humidity sensor probes in the callus chamber 1 are collected and recorded every minute.

(4) Sample surface and core temperature determination: after each batch of sweet potatoes are subjected to heat shock callus pretreatment or cooling pretreatment according to the pretreatment method of the embodiment, the surface temperature and the core temperature of the sweet potatoes in the upper, middle and lower layers in two rows of 12 baskets in the same batch are measured according to the sampling method illustrated in fig. 4. The measurement method is as follows: immediately after taking out the pretreated sweet potatoes from the sweet potato basket 16, three points were randomly measured on the upper, middle and lower sides of the surface layer (3mm depth) and the inside (30mm depth) of each sweet potato using a probe thermometer, the surface layer and the inside temperature were recorded, respectively, and the average value of all the sampling points was calculated.

FIG. 5 shows the temperature changes detected by the temperature sensor probes in the callus chamber 1 during the high-temperature short-time callus formation of sweet potato in the callus chamber 1. The test result shows that the callus chamber 1 in the device has uniform temperature control and small fluctuation in the running process of high-temperature short-time callus. The temperature sensors at six different positions, namely the upper position, the lower position, the middle position and the rear position, monitor the highest temperature of 64.84 ℃, the lowest temperature of 63.02 ℃, and the temperature difference is only 1.82 ℃. The test result shows that the callus chamber 1 in the device has better temperature stability when processing 750kg results in large batch, and can heat and shock sweet potatoes in different placing positions uniformly, thereby ensuring the heat shock effect.

FIG. 6 shows the change of humidity detected by each humidity sensor probe in the callus chamber 1 during the high-temperature short-time callus treatment of sweet potato in the callus chamber 1. Because the cleaning process is involved in the pretreatment process of the equipment, a large amount of moisture is adhered to the surface of the sweet potato, the treatment uniformity of the subsequent high-temperature short-time heat shock process is influenced, the high-humidity load is caused to the components in the equipment, and the service life of the equipment is influenced. Therefore, the problems can be solved by arranging the electric air inlet valve and the moisture exhaust fan in the equipment. The test result shows that the humidity of the callus chamber 1 in the device is well controlled in the process of running high-temperature short-time callus. The average humidity of the six probes is 25.45%, and the humidity fluctuation is within 2.5%. The test results show that the callus chamber 1 in the apparatus of the present invention has better humidity stability when processing 750kg results in large batches, does not cause the problem of excessive humidity in narrow chambers, and ensures the heat shock effect.

FIG. 7 shows the temperature of the outer skin and inner core (i.e., sweet potato center) of sweet potatoes in bulk after a high-temperature short-time callus process in the callus chamber 1. After the sweet potato is subjected to the heat shock pretreatment in the callus chamber 1, the skin temperature of the sweet potato is generally lower than the core temperature, the skin temperature is between 37.78 and 39.70 ℃, and the difference of the skin temperature of the sweet potato at each sampling point is not more than 2 ℃; the temperature of the inner core is between 40.22 and 40.88 ℃, and the temperature difference of the inner core of the sweet potato at each sampling point is not more than 0.7 ℃. The test result shows that the high-temperature short-time heat shock equipment in the equipment has uniform heating effect on the sweet potatoes, does not have large temperature difference, and ensures that the sweet potatoes processed in the same batch at different positions can be well pre-treated by heat shock.

FIG. 8 shows the temperature of the outer skin and inner core (i.e., sweet potato center) of a batch of sweet potatoes after the rapid cooling process by strong wind in the cooling chamber 2. In the traditional sweet potato pretreatment flow, the cooling process after heating is not specially designed, so that the sweet potatoes stacked and bagged are not uniformly cooled after being heated, and are slowly cooled in the storage process, the premature aging of the sweet potatoes is stimulated, and the surfaces of the sweet potatoes form respiratory condensate water, so that a large amount of rotting is caused. In the integrated pretreatment equipment, sweet potatoes are specially cooled by the cooling chamber 2. The test result shows that after the sweet potato is cooled and pretreated by the cooling chamber 2, the skin temperature of the sweet potato is also lower than the core temperature, the skin temperature is rapidly reduced to 14.82-15.44 ℃ from 37.78-39.70 ℃ after heat shock, and the difference of the skin temperature of the sweet potato at each sampling point is not more than 1 ℃; the temperature of the inner core is reduced to 15.26-16.58 ℃ from 40.22-40.88 ℃ after heat shock, and the temperature difference of the inner core of the sweet potato at each sampling point is not more than 1.5 ℃. The test result shows that the cooling effect of the cooling equipment in the equipment disclosed by the invention on the thermally excited sweet potatoes is obvious, the cooling effect is uniform, and large temperature difference does not occur, so that the sweet potatoes processed in the same batch at different positions can be well cooled and pretreated, and the quality of the sweet potatoes in the storage process is ensured.

And (II) testing and verifying the performances of the pretreated sweet potatoes: the following 1 example and 4 comparative examples are used to compare and verify the performance indexes of sweet potatoes which are subjected to callus and cooling pretreatment in the sweet potato storage pretreatment equipment. In order to avoid the influence of the difference of the wound on the test result, the experiment is carried out by using the sweet potato tuber after artificial injury.

The specific method comprises the following steps:

(1) selecting: fresh sweet potatoes which are regular in appearance, uniform in size (weight is 200-300 g), free of damage and diseases and insect pests are selected from the field and collected in the sweet potato Siheshui.

(2) Artificial injury: in order to ensure the accuracy of the experiment, the sweet potatoes used for the experiment are subjected to artificial wound manufacturing. Wiping a skin scraping knife and a puncher (the diameter is 20mm) with 95% ethanol for disinfection, firstly, making a circular mark with the radius of 1cm on each sweet potato by using the puncher, then, scraping wounds with the diameter of 2cm and the depth of 3mm on the surface of the sweet potato along the marked part of the puncher by using the skin scraping knife, and dividing each sweet potato into an upper wound, a middle wound and a lower wound which are 6 parts; the skin-scraping knife is a stainless steel foot filing knife (the length is 190mm, the width is 26mm, and the thickness is 15 mm).

(3) The artificially injured sweet potatoes were randomly sampled and used as samples of example 1 and comparative examples 1 to 4, respectively, 400 sweet potatoes were treated for each group, and 3 groups were repeated. Wherein: