A spray impregnation vacuum freeze drying integrated equipment

Abstract

The invention relates to a spray impregnation vacuum freeze drying integrated equipment, and also to a corresponding method, belonging to the technical field of food equipment. A U-shaped impregnation liquid delivery pipe is arranged inside the freeze drying bin of the equipment, the lower end of which extends from the bottom of the freeze drying bin and is connected to the impregnation liquid tank, and the upper end is connected to the nozzle delivery pipe, and the nozzle delivery pipe is provided with an atomizing nozzle, and the impregnation liquid is delivered to the atomizing nozzle and sprayed on the surface of the material; at the same time, two groups of refrigeration systems and raw water collection systems are arranged, which are respectively connected to the freeze drying bin through two butterfly valves, and the butterfly valve is switched so that one group of refrigeration systems and raw water collection systems perform freeze drying refrigeration and raw water vapor condensation, and the other group performs raw water ice melting and raw water collection. The present invention avoids the loss of nutrients by atomizing and spraying the impregnation liquid after vacuum freeze drying, realizes the pre-drying, vacuum impregnation, freezing, and post-drying processes in one device, greatly improves the processing efficiency of dried fruit and vegetable products, and at the same time, the fruit and vegetable raw water collection system is used to recover the water and flavor and pigment substances removed during the vacuum freeze drying process, and realizes the comprehensive utilization of fruit and vegetable raw water and flavor pigments.

Description

Technical Field

[0001] The invention relates to fruit and vegetable drying and processing equipment, in particular to spray-impregnation vacuum freeze-drying integrated equipment, belonging to the technical field of food equipment. Background Art

[0002] Vacuum freeze drying is an internationally recognized processing method for producing high-quality, high-value-added dehydrated foods. It keeps the material in a frozen state and removes moisture from the material by sublimating ice into water vapor at low temperature and low pressure. This can maintain the original organizational structure of the material and retain the various nutrients in the fresh material to the greatest extent. It is currently the best method for producing high-quality dried products.

[0003] Since vacuum freeze-dried fruit and vegetable products often have a soft taste and lack a crisp texture, vacuum impregnation pretreatment is often used in production to increase the solid content of fruit and vegetable materials and improve the taste and texture of vacuum freeze-dried products. Some vacuum impregnation processes are performed before vacuum freeze drying, while others are performed after vacuum freeze drying and then vacuum freeze drying for the second time. Either method requires independent vacuum impregnation equipment. At present, there are reports of patents for vacuum impregnation equipment. Patent CN 215403911U reports a vacuum impregnation device, including a furnace body and a furnace cover arranged on the furnace body. The furnace body is divided into chambers of different capacities by setting a partition plate. When impregnating products of different sizes, the corresponding chamber can be selected. The chambers of different capacities are connected by pipes, and multiple products to be impregnated can be vacuum impregnated in multiple chambers at the same time. Patent CN 216237888U reports a vacuum impregnation device, including a base, an impregnation tank, a vacuum mechanism and a control cabinet. The impregnation tank is fixed to the upper surface of the base. The impregnation tank includes a tank body and a heating system. The tank body includes an outer tank and an inner tank. The side wall of the outer tank is provided with a liquid inlet, a liquid outlet and a cover plate. The side wall of the inner tank is provided with an air suction port and a pressure relief port. The air suction port is connected to the vacuum mechanism through an evacuation pipe.

[0004] These patents mainly improve materials and scope of use. After vacuum impregnation, the materials still need to be continuously transferred between equipment for other processes, which is cumbersome, costly and inefficient. At the same time, during the vacuum impregnation process, the materials need to be immersed in the impregnation liquid. The nutrients in the materials will dissolve during the impregnation process, which also changes the content composition of the impregnation liquid. It is impossible to control the relative stability of the impregnation liquid for each batch of materials, resulting in a large amount of waste of the impregnation liquid. Summary of the invention

[0005] Technical issues

[0006] The purpose of the present invention is to propose a spray impregnation vacuum freeze drying integrated equipment in view of the above problems. The equipment arranges the spray device of the impregnation liquid spray system in the freeze drying chamber of the vacuum freeze drying, so that the two functions of vacuum impregnation and vacuum freeze drying are completed in one equipment. At the same time, through two groups of refrigeration units and raw water collection systems, the vacuum freeze drying can be switched between drying and ice melting without stopping the vacuum freeze drying equipment for ice melting. The raw water, flavor and pigment substances removed during the vacuum freeze drying of fruits and vegetables can be collected, so as to realize the secondary utilization of the raw water of fruits and vegetables and reduce the loss of nutrients in fruits and vegetables.

[0007] Technical Solution

[0008] A spray impregnation vacuum freeze drying integrated device, comprising a freeze drying chamber (1), a cold trap chamber A (2) and a cold trap chamber B (3), a vacuum unit, a refrigeration unit A (4) and a refrigeration unit B (5), a heater (6), an impregnation liquid spray system, and a raw water collection system; characterized in that: the bottom end of the freeze drying chamber (1) is connected to the impregnation liquid spray system, the freeze drying chamber (1) is connected to the cold trap chamber A (2) and the cold trap chamber B (3) through a butterfly valve A (7) and a butterfly valve B (8), and the other ends of the cold trap chamber A (2) and the cold trap chamber B (3) are connected through The butterfly valve C (9) and the butterfly valve D (10) are connected to a vacuum unit, which is composed of two roots pumps (11) connected in series and two water ring pumps (12) connected in parallel. The cold trap chamber A (2) and the cold trap chamber B (3) are connected to the refrigeration unit A (4) and the refrigeration unit B (5) respectively, and the bottom ends are connected to two raw water collection systems respectively. The heater (6) is connected to the heating partition (13) in the freeze-drying chamber (1), and is connected to the heating coil A (14) and the heating coil B (15) in the cold trap chamber A (2) and the cold trap chamber B (3) respectively.

[0009] The impregnation liquid spray system is composed of a U-shaped impregnation liquid delivery pipe (16), a nozzle delivery pipe (17), an atomizing nozzle (18), an impregnation liquid tank (19), an external delivery pipeline (20), a high-pressure pump (21), and a flow regulating valve (22). The U-shaped impregnation liquid delivery pipe (16) is arranged on both sides of the inner wall of the tank body of the freeze-drying bin (1). The nozzle delivery pipe (17) is arranged between the heating partition (13) and the material tray (23), and one end is connected to the U-shaped impregnation liquid delivery pipe (16). A certain number of atomizing nozzles (18) are arranged on the nozzle delivery pipe (17). The bottom end of the U-shaped impregnation liquid delivery pipe (16) is connected to the impregnation liquid tank (19) through the external delivery pipeline (20), and a high-pressure pump (21) and a flow regulating valve (22) are arranged in the middle.

[0010] The two raw water collection systems are respectively composed of a raw water collection box A (24) and a raw water collection box B (25), a vacuum diaphragm valve A (26) and a vacuum diaphragm valve B (27), a pressure relief valve A (28) and a pressure relief valve B (29), and a drain valve A (30) and a drain valve B (31). The raw water collection box A (24) and the raw water collection box B (25) are respectively connected to the cold trap chamber A (2) and the cold trap chamber B (3), and a vacuum diaphragm valve A (26) and a vacuum diaphragm valve B (27) are respectively arranged in the middle. The upper end of the raw water collection box is provided with a pressure relief valve A (28) and a pressure relief valve B (29), and the lower end is provided with a drain valve A (30) and a drain valve B (31).

[0011] The material is placed on a material tray (23) and placed in a freeze-drying chamber (1). The refrigeration unit A (4) and the roots pump (11) and the water ring pump (12) in the vacuum unit are started. After the material is vacuum freeze-dried to a certain moisture content, the high-pressure pump (21) of the impregnation liquid spray system is turned on, and the impregnation liquid is transported to the U-shaped impregnation liquid delivery pipe (16) through the external delivery pipe (20). The impregnation liquid is then transported to the atomizing nozzle (18) through the nozzle delivery pipe (17). The atomizing nozzle (18) atomizes the impregnation liquid into small droplets and sprays them onto the surface of the material. Then, the pressure relief valve C (32) is slowly opened. The impregnation liquid is impregnated into the material under the action of positive and negative pressures inside and outside the cell. The atomizing nozzle (18) is continuously opened to spray the impregnation liquid according to the impregnation speed of the impregnation liquid. The flow rate of the impregnation liquid is regulated by the flow regulating valve (22).

[0012] During the vacuum freeze-drying process, ice in the material is directly sublimated into water vapor and brought into the cold trap A (2) under the action of the vacuum unit. Under the action of the refrigeration unit A (4), the water vapor is quickly frozen into ice and covers the interior of the cold trap A (2). When the water vapor condenses to a certain extent, the butterfly valve A (7) and the refrigeration unit A (4) are closed, and the butterfly valve B (8) and the refrigeration unit B (5) are opened. The water vapor condenses into ice in the cold trap B (3) through the butterfly valve B (8). At this time, the heating coil A (14) in the cold trap A (2) is opened, and the heating coil A (14) is heated by the heater. The transported heat source melts the ice frozen in the cold trap A (2) into water, closes the drain valve A (30), opens the vacuum diaphragm valve A (26) and the pressure relief valve A (28), and transports the raw water removed from the material in the cold trap A (2) to the raw water collection tank A (24). When the raw water in the raw water collection tank A (24) reaches a certain height, closes the vacuum diaphragm valve A (26), discharges the raw water in the material through the drain valve A (30), and then closes the pressure relief valve A (28), and circulates and opens the cold trap A (2) and the cold trap B (3) to collect the raw water of the material.

[0013] Beneficial Effects

[0014] The equipment of the present invention relates to a fruit and vegetable drying and processing equipment, in particular to a spray impregnation vacuum freeze drying integrated equipment. A U-shaped impregnation liquid delivery pipe is provided in the freeze drying chamber of the equipment, one end of which is connected to the nozzle delivery pipe, a certain number of atomizing nozzles are provided on the nozzle delivery pipe, and the other end is connected to an external delivery pipeline, which is connected to an impregnation liquid tank through the external delivery pipeline. The work of vacuum freeze drying equipment, vacuum impregnation equipment and freezing equipment is completed by one equipment, avoiding the transfer of materials between multiple equipments, saving labor input and equipment cost investment, and improving production efficiency.

[0015] In the impregnation liquid spray system described in the present invention, the atomizing nozzle is arranged between the heating partition and the material tray. During the spray impregnation process, the impregnation liquid is sprayed on the surface of the material and is quickly impregnated into the interior of the material under the action of positive and negative pressures inside and outside the cell, thereby avoiding the change in the concentration of the impregnation liquid caused by traditional vacuum impregnation of a large amount of material, which makes it difficult to achieve precise control, retains a large amount of nutrients in the material, and avoids a large amount of waste of the impregnation liquid.

[0016] The cold trap described in the present invention is connected with two groups of refrigeration units and a raw water collection system. Through the conversion between the two groups of refrigeration units, raw water collection is achieved on the basis of ensuring continuous freeze-drying. When preparing the impregnation liquid, the fruit and vegetable raw water is added to re-endow the fruits and vegetables with volatile flavor substances and pigment substances lost in the freeze-drying process, and at the same time, the secondary utilization of the fruit and vegetable raw water is achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the structure of the spray impregnation vacuum freeze drying integrated equipment;

[0018] Figure 2 for Figure 1 Schematic diagram of the cross-sectional structure of the freeze-drying chamber;

[0019] In the figure: 1-freeze drying chamber, 2-cold trap chamber A, 3-cold trap chamber B, 4-refrigeration unit A, 5-refrigeration unit B, 6-heater, 7-butterfly valve A, 8-butterfly valve B, 9-butterfly valve C, 10-butterfly valve D, 11-Roots pump, 12-water ring pump, 13-heating baffle, 14-heating coil A, 15-heating coil B, 16-U-type impregnation liquid delivery pipe, 17-nozzle delivery pipe, 18-atomizing nozzle, 19-impregnation liquid tank, 20-external delivery pipeline, 21-high pressure pump, 22-flow regulating valve, 23-material tray, 24-raw water collection box A, 25-raw water collection box B, 26-vacuum diaphragm valve A, 27-vacuum diaphragm valve B, 28-pressure relief valve A, 29-pressure relief valve B, 30-drain valve A, 31-drain valve B, 32-pressure relief valve C. DETAILED DESCRIPTION

[0020] Embodiment 1

[0021] The spray impregnation vacuum freeze drying integrated equipment of the present invention is as follows Figure 1 and Figure 2 As shown, it includes a freeze-drying chamber 1, a cold trap chamber A 2 and a cold trap chamber B 3, a vacuum unit, a refrigeration unit A 4 and a refrigeration unit B 5, a heater 6, an impregnation liquid spray system, and a raw water collection system. In order to realize raw water collection under the condition of continuous freeze drying, the equipment is provided with two sets of refrigeration systems and raw water collection systems. The freeze drying chamber 1 is connected with the cold trap chamber A2 and the cold trap chamber B3 through butterfly valve A7 and butterfly valve B8. The other ends of the cold trap chamber A2 and the cold trap chamber B3 are connected with the vacuum unit through butterfly valve C9 and butterfly valve D10 respectively, and are connected with the refrigeration unit A4 and the refrigeration unit B5 respectively. The bottom ends are connected with the two raw water collection systems respectively. The heater 6 is connected with the heating partition 13 in the freeze drying chamber 1, and is connected with the heating coil A14 and the heating coil B15 in the cold trap chamber A2 and the cold trap chamber B3 respectively. The two raw water collection systems are respectively composed of raw water collection box A24 and raw water collection box B25, vacuum diaphragm valve A26 and vacuum diaphragm valve B27, pressure relief valve A28 and pressure relief valve B29, drain valve A30 and drain valve B31. 31, raw water collection tank A24 and raw water collection tank B25 are connected to cold trap bin A2 and cold trap bin B3 respectively, vacuum diaphragm valve A26 and vacuum diaphragm valve B27 are respectively arranged in the middle, pressure relief valve A28 and pressure relief valve B29 are arranged at the upper end of the raw water collection tank, and drain valve A30 and drain valve B31 are arranged at the lower end; by switching butterfly valve A7 and butterfly valve B8, one group of refrigeration system and raw water collection system performs freeze-drying refrigeration and raw water vapor condensation, and the other group performs raw water ice melting and raw water collection through heat source transportation of heater 6, and the other ends of the two groups of refrigeration systems are connected to the same vacuum unit, and the vacuum degree of the two groups of refrigeration systems is changed by switching butterfly valve C9 and butterfly valve D10.

[0022] The impregnation liquid spray system is composed of a U-shaped impregnation liquid delivery pipe 16, a nozzle delivery pipe 17, an atomizing nozzle 18, an impregnation liquid tank 19, an external delivery pipeline 20, a high-pressure pump 21, and a flow regulating valve 22. The U-shaped impregnation liquid delivery pipe 16, the nozzle delivery pipe 17, and the atomizing nozzle 18 are located inside the freeze-drying bin 1. The lower end of the U-shaped impregnation liquid delivery pipe 16 extends from the bottom end of the freeze-drying bin 1 and is connected to the impregnation liquid tank through the external delivery pipeline 20. The U-shaped impregnation liquid delivery pipe 16 is arranged on both sides of the inner wall of the tank body of the freeze-drying bin 1. The nozzle delivery pipe 17 is arranged between the heating baffle 13 and the material tray 23, and one end is connected to the U-shaped impregnation liquid delivery pipe 16. A certain number of atomizing nozzles 18 are arranged on the nozzle delivery pipe 17 to ensure that the impregnation liquid mist sprayed by the nozzle is evenly sprayed onto the surface of the material.

[0023] When the equipment of this embodiment is in operation, the corresponding spray impregnation vacuum freeze drying process includes the following main steps:

[0024] Step 1: vacuum freeze drying: evenly spread the frozen fruit and vegetable materials on the material tray 23, put them into the freeze drying chamber, turn on the refrigeration unit A4 and the butterfly valve A7, the vacuum unit and the butterfly valve C9, close the butterfly valve B8 and the butterfly valve D10, and perform the first vacuum freeze drying. During the vacuum freeze drying process, the ice in the material is directly sublimated into water vapor, which is brought into the cold trap chamber A2 under the action of the vacuum unit. Under the action of the refrigeration unit A4, the water vapor is quickly frozen into ice and covers the inside of the cold trap chamber A2. When the water vapor condenses to a certain degree, turn off the refrigeration unit A4, the butterfly valve A7 and the butterfly valve C9, turn on the refrigeration unit B5, the butterfly valve B8 and the butterfly valve D10, and the water vapor condenses into ice in the cold trap chamber B3 through the butterfly valve B8;

[0025] Step 2: Raw water collection: Open the heating coil A14 in the cold trap A2, melt the frozen ice in the cold trap A2 into water through the heat source delivered by the heater, close the drain valve A30, open the vacuum diaphragm valve A26 and the pressure relief valve A28, and deliver the raw water removed from the material in the cold trap A2 to the raw water collection tank A24. When the raw water in the raw water collection tank A24 reaches a certain height, close the vacuum diaphragm valve A26, and discharge the raw water in the material through the drain valve A30. After the above steps, open the cold trap A2 and the cold trap B3 in a cycle to collect the raw water of the material.

[0026] Step 3: Spray impregnation: the impregnation liquid is prepared by mixing the raw water of fruits and vegetables obtained in the second step, and the prepared impregnation liquid is put into the impregnation liquid tank 19. The high-pressure pump 21 of the impregnation liquid spray system is turned on, and the impregnation liquid is transported to the U-shaped impregnation liquid delivery pipe 16 through the external delivery pipe 20. The impregnation liquid is then transported to the atomizing nozzle 18 through the nozzle delivery pipe 17. The atomizing nozzle 18 atomizes the impregnation liquid into small droplets and sprays them onto the surface of the material. Then, the pressure relief valve C 32 is slowly opened. The impregnation liquid is impregnated into the material under the action of positive and negative pressures inside and outside the cell. The atomizing nozzle 18 is continuously opened to spray the impregnation liquid according to the impregnation speed of the impregnation liquid. The flow rate of the impregnation liquid is regulated by the flow regulating valve 22.

[0027] Step 4: Secondary vacuum freeze drying: After the vacuum impregnation is completed, the impregnated material is frozen by the refrigeration unit A 4 or the refrigeration unit B 5, and then the vacuum unit is turned on for the second vacuum freeze drying. After the drying is completed, the pressure relief valve C 32 is opened to take out the product.

Claims

1. A spray impregnation vacuum freeze drying integrated equipment, comprising a freeze drying chamber (1), a cold trap chamber A (2) and a cold trap chamber B (3), a vacuum unit, a refrigeration unit A (4) and a refrigeration unit B (5), a heater (6), an impregnation liquid spray system, and a raw water collection system; characterized in that: The bottom end of the freeze drying chamber (1) is connected to the impregnation liquid spray system. The freeze drying chamber (1) is connected to the cold trap chamber A (2) and the cold trap chamber B (3) through butterfly valve A (7) and butterfly valve B (8). The other ends of the cold trap chamber A (2) and the cold trap chamber B (3) are connected to a vacuum unit through butterfly valve C (9) and butterfly valve D (10), respectively. The vacuum unit is composed of two roots pumps (11) connected in series and two water ring pumps (12) connected in parallel. The cold trap chamber A (2) and the cold trap chamber B (3) are connected to a refrigeration unit A (4) and a refrigeration unit B (5) respectively. The bottom ends are connected to two raw water collection systems respectively. The heater (6) is connected to a heating partition (13) in the freeze drying chamber (1), and is connected to a heating coil A (14) and a heating coil B (15) in the cold trap chamber A (2) and the cold trap chamber B (3) respectively. The impregnation liquid spray system is composed of a U-shaped impregnation liquid delivery pipe (16), a nozzle delivery pipe (17), an atomizing nozzle (18), an impregnation liquid tank (19), an external delivery pipeline (20), a high-pressure pump (21), and a flow regulating valve (22). The U-shaped impregnation liquid delivery pipe (16) is arranged on both sides of the inner wall of the tank body of the freeze-drying bin (1). The nozzle delivery pipe (17) is arranged between the heating partition (13) and the material tray (23), and one end is connected to the U-shaped impregnation liquid delivery pipe (16). A certain number of atomizing nozzles (18) are arranged on the nozzle delivery pipe (17). The bottom end of the U-shaped impregnation liquid delivery pipe (16) is connected to the impregnation liquid tank (19) through the external delivery pipeline (20), and a high-pressure pump (21) and a flow regulating valve (22) are arranged in the middle. The two raw water collection systems are respectively composed of a raw water collection box A (24) and a raw water collection box B (25), a vacuum diaphragm valve A (26) and a vacuum diaphragm valve B (27), a pressure relief valve A (28) and a pressure relief valve B (29), and a drain valve A (30) and a drain valve B (31). The raw water collection box A (24) and the raw water collection box B (25) are respectively connected to the cold trap chamber A (2) and the cold trap chamber B (3), and a vacuum diaphragm valve A (26) and a vacuum diaphragm valve B (27) are respectively arranged in the middle. The upper end of the raw water collection box is provided with a pressure relief valve A (28) and a pressure relief valve B (29), and the lower end is provided with a drain valve A (30) and a drain valve B (31).

2. The spray impregnation vacuum freeze drying integrated equipment according to claim 1, characterized in that: The material is placed on a material tray (23) and placed in a freeze-drying chamber (1). The refrigeration unit A (4) and the roots pump (11) and the water ring pump (12) in the vacuum unit are started. After the material is vacuum freeze-dried to a certain moisture content, the high-pressure pump (21) of the impregnation liquid spray system is turned on, and the impregnation liquid is transported to the U-shaped impregnation liquid delivery pipe (16) through the external delivery pipe (20). The impregnation liquid is then transported to the atomizing nozzle (18) through the nozzle delivery pipe (17). The atomizing nozzle (18) atomizes the impregnation liquid into small droplets and sprays them onto the surface of the material. Then, the pressure relief valve C (32) is slowly opened. The impregnation liquid is impregnated into the material under the action of positive and negative pressures inside and outside the cell. The atomizing nozzle (18) is continuously opened to spray the impregnation liquid according to the impregnation speed of the impregnation liquid. The flow rate of the impregnation liquid is regulated by the flow regulating valve (22).

3. A spray impregnation vacuum freeze drying integrated equipment according to claim 1 or 2, characterized in that: During the vacuum freeze-drying process, ice in the material is directly sublimated into water vapor and brought into the cold trap A (2) under the action of the vacuum unit. Under the action of the refrigeration unit A (4), the water vapor is quickly frozen into ice and covers the interior of the cold trap A (2). When the water vapor condenses to a certain extent, the butterfly valve A (7) and the refrigeration unit A (4) are closed, and the butterfly valve B (8) and the refrigeration unit B (5) are opened. The water vapor condenses into ice in the cold trap B (3) through the butterfly valve B (8). At this time, the heating coil A (14) in the cold trap A (2) is opened, and the heating coil A (14) is heated by the heater. The transported heat source melts the ice frozen in the cold trap A (2) into water, closes the drain valve A (30), opens the vacuum diaphragm valve A (26) and the pressure relief valve A (28), and transports the raw water removed from the material in the cold trap A (2) to the raw water collection tank A (24). When the raw water in the raw water collection tank A (24) reaches a certain height, closes the vacuum diaphragm valve A (26), discharges the raw water in the material through the drain valve A (30), and then closes the pressure relief valve A (28), and circulates and opens the cold trap A (2) and the cold trap B (3) to collect the raw water of the material.

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