CN114557434A

CN114557434A - Pretreatment process for realizing efficient puffing and drying of betel nuts by combining superheated steam and microwaves

Info

Publication number: CN114557434A
Application number: CN202210281164.0A
Authority: CN
Inventors: 陈祁衡; 朱珺玎; 唐露; 陈坤
Original assignee: Hunan Wuzizui Industrial Group Co ltd
Current assignee: Hunan Wuzizui Industrial Group Co ltd
Priority date: 2022-03-22
Filing date: 2022-03-22
Publication date: 2022-05-31

Abstract

The invention relates to a food processing technology, in particular to a pretreatment technology for realizing efficient puffing and drying of areca nuts by combining superheated steam and microwaves. The process adopts microwave and superheated steam combined treatment, not only can soften fiber, but also can carry out rapid drying. The process improves the existing curing, sterilizing and baking processes, and aims to disperse and soften the fiber of the betel nut, dry and comfortable betel nut kernels, non-carbonized seed surfaces and non-broken seeds during puffing on the premise of ensuring the quality and the taste of the betel nuts, so that the problems of large using amount of conventional puffing steam and long consumed time are solved; meanwhile, the problems of water accumulation in the inner cavity of the betel nut, high baking difficulty and low production efficiency are solved.

Description

Pretreatment process for realizing efficient puffing and drying of betel nuts by combining superheated steam and microwaves

Technical Field

The invention relates to a food processing technology, in particular to a pretreatment process for realizing efficient puffing and drying of areca nuts by combining superheated steam and microwaves.

Background

Betel nut is a seed of areca nut of the palmaceae family, and as a leisure food, there are various product forms of areca nut, including fresh areca nut, a product prepared by drying an inner kernel of areca nut and mixing with other seasonings, an areca nut chewing product prepared by drying fresh fruit and deep processing, and the like, and at present, fresh areca nut and edible areca nut are the main raw materials in China.

Edible areca in Hunan province is a deep-processed product of areca, fresh areca is made into dry areca by deactivating enzymes and drying, then the dry areca is used as a main raw material, and is matched with specially-made ingredients such as brine, edible essence and the like, and the edible areca is produced by a series of complex processes such as seed soaking, cooking, fermentation, baking, aroma sealing, seed pressing, gluing, seed cutting, kernel removal, brine dropping and the like.

Wherein, drying is one of the most important and most critical steps or modes in the primary processing of betel nuts, and the drying process directly determines the quality of betel nut products. The traditional areca is baked by adopting a single hot air drying method, the areca processed by the method has the defects of dry and hard fiber, long baking time, uneven water inside and outside the areca, and the like, and can generate mechanical stimulation to the oral cavity of a consumer during chewing, so that the texture of the oral mucosa is thickened, inflammation is caused, and oral lesions are easily caused after long-term chewing. Secondly, the traditional process generally needs to carry out cooking explosion pretreatment before the areca nuts are dried, and the pretreatment is also an important link in the areca nut processing. The hardness of the betel nuts which are not subjected to softening treatment after being dried is large, the betel nuts are not beneficial to processing and chewing, although the wooden structure of the betel nuts can be damaged by adopting cooking blasting, water can quickly escape in the subsequent drying process, the drying time is shortened, and partial effects of sterilization and enzyme inactivation are achieved, the moisture content of the betel nuts after the cooking blasting is high, the water accumulation and nucleus fester in the inner cavity of the betel nuts are easily caused, and the subsequent baking difficulty is increased; meanwhile, the active ingredients are lost, so that the tail of the end product is short and the taste is sweet; excessive damage to the structure and chemical components of betel nuts can also lead to problems such as residue removal of the end product.

Therefore, in order to improve the softness and the taste of the betel nuts, improve the quality of products and shorten the production time, it is imperative to upgrade the betel nut puffing and drying process.

Disclosure of Invention

The invention aims to provide a pretreatment process for realizing efficient puffing and drying of areca nuts by combining superheated steam and microwaves.

The purpose of the invention is realized by the following ways: a pretreatment process for realizing efficient puffing and drying of areca nuts by combining superheated steam and microwaves comprises the following steps:

firstly, rehydrating dry areca nuts;

A. filling the betel nut dried fruits which are subjected to impurity removal and grading screening into a brewing tank;

B. injecting rehydration feed liquid into the brewing tank for rehydration, and setting the working conditions of the temperature of 20-30 ℃, the time of 7-12 hours and the rotating speed of 2-5 circles per hour;

C. taking out and airing to obtain the rehydrated areca nuts;

step two, swelling and sterilizing the areca nuts;

A. putting the rehydrated areca nuts into a compound dryer;

B. carrying out superheated steam treatment on the areca nuts, wherein the steam pressure is 0.4-0.5MPa, and the superheated steam temperature is 155-;

C. after the superheated steam treatment is carried out for 1-3 minutes, the microwave treatment is added to the areca nuts while the superheated steam treatment is continued, the microwave frequency is set to be 2450 +/-15 MHZ, the power is 280-960w, and the time is 0.5-6 minutes;

D. taking out to obtain the expanded areca nut;

step three, performing biological enzymolysis on the areca nuts for flavoring;

A. filling the swelled areca nuts into a seasoning tank, and pouring the compound softening enzyme liquid, the feed liquid and water into the seasoning tank;

B. setting operation conditions for enzymolysis and flavoring, wherein the temperature is 50-60 ℃, the time is 36-48 hours, and the rotation speed is 2-5 circles every half hour;

C. taking out to obtain areca nuts after being subjected to enzymolysis and flavoring;

step four, baking and drying the areca nuts;

A. putting the areca nuts subjected to enzymolysis and flavoring into a composite dryer for superheated steam and microwave synchronous treatment, wherein the working conditions are as follows: setting the steam pressure of 0.4-0.5MPa, the superheated steam temperature of 155-;

B. drying the areca nuts dried by superheated steam-microwave combination in an oven with hot air at 80 deg.C until the water content is 18-21%.

As a further limitation of the invention, the rehydration solution in the step one is composed of water and soda ash, and 2000-3000 parts of water and 10-20 parts of soda ash are added into every 1000 parts of the dry areca nuts according to the weight part ratio.

As a further limitation of the invention, in the areca nut rehydration process in the first step, the moisture value of the areca nut before rehydration is controlled to be 8-17%, and the moisture value of the obtained areca nut after rehydration is controlled to be 30-36%.

As a further limitation of the invention, in the second step, when the areca nut is expanded and sterilized, the stacking height of the areca nut in the composite puffing machine is controlled to be 2-15cm, and the cavity breaking rate is controlled to be below 1%.

In the third step, 2-6 parts of compound softening enzyme liquid, 50-100 parts of water and 1 part of feed liquid are added into every 1000 parts of dry areca nuts.

As a further limitation of the present invention, in step three, the composite softening enzyme comprises the following components in parts by weight: 0.5-1.5 parts of cellulase, 0.5-1.5 parts of xylanase, 0.25-1 part of glucanase and 0.2-1 part of mannase.

As a further limitation of the invention, in the third step, the feed liquid comprises the following components in parts by weight: 5-8 parts of sodium cyclamate, 30-50 parts of white sugar, 1-2 parts of aspartame, 3-5 parts of saccharin, 1-3 parts of salt, 8-10 parts of orange oil and 150 parts of water.

As a further limitation of the invention, in the fourth step, when the areca nuts are baked and dried, the stacking height of the areca nuts in the composite puffing machine is controlled to be 2-15cm, the cavity breaking rate is controlled to be below 2%, and the moisture value after the areca nuts are dried by hot air at 80 ℃ is controlled to be 18-21%.

The invention relates to a pretreatment process for realizing efficient puffing and drying of betel nuts by combining superheated steam and microwaves, which improves the curing, sterilizing and baking processes in the prior art, and compared with the prior art, the invention has the advantages that:

1. the superheated steam and the microwave combined treatment have high-efficiency synergistic effect, in the treatment process of the superheated steam, water vapor is condensed on the surfaces of the areca nuts, the temperature of seed surfaces can be rapidly increased, meanwhile, the superheated steam efficiently penetrates the areca nuts to accelerate the movement of water molecules, so that pressure difference is formed between the interior and the exterior of the areca nuts, and an expansion effect is achieved;

2. the microwave energy can rapidly heat the inside and outside of the areca (especially the areca with high water content in the inner cavity), the water molecules do molecular motion from inside to outside, and the internal and external pressure difference changes instantly to generate the effect of puffing. Because the inside and outside are heated evenly, the drying rate is rapid and stable, the microwave and superheated steam combined treatment process has the advantages of large drying rate, energy conservation, high production efficiency, clean production, easy realization of automatic control, improvement of drying quality and the like.

The areca nut expansion sterilization method related by the invention is adopted to improve the original cooking, curing and sterilization technology, and has the effects that:

1. no sewage is discharged, the method is clean and environment-friendly, and the discharged materials are only water vapor and a small amount of condensed water;

2. energy is saved, and the generated steam can be reused;

3. microwave and superheated steam are adopted for puffing and sterilization, a pressure container is not used, the operation is safer, and the production is more efficient;

4. the areca nuts are heated uniformly, so that the inside and the outside of the areca nuts can be effectively sterilized, and the softness of fibers is improved;

5. the betel nut is easier to be tasty after being swelled, and the leavening time is shortened.

The method for baking and drying the areca nuts improves the original single hot air drying technology, and has the effects that:

1. the problems of long drying and baking time, low production efficiency and high energy consumption of single hot air are solved;

2. solves the problems of water accumulation in the inner cavity of the betel nut, wet and soft core, uneven internal and external water content and large baking difficulty;

3. solves the problems of difficult kernel removal and low labor efficiency of the betel nut post-procedure.

Drawings

The invention is described in further detail below with reference to the accompanying drawings:

FIG. 1 is a schematic view of the overall structure of a composite dryer used in the present invention;

FIG. 2 is a schematic view of a feeding device of the composite dryer used in the present invention;

FIG. 3 is a second schematic view of the structure of a feeding device of the composite dryer used in the present invention;

FIG. 4 is a schematic structural diagram of a composite drying apparatus in the composite dryer used in the present invention;

FIG. 5 is a second schematic view of the composite drying device of the composite dryer used in the present invention;

FIG. 6 is a schematic structural diagram of a discharging device in the composite dryer used in the present invention;

FIG. 7 is a second schematic view of the structure of the discharging device of the composite dryer used in the present invention;

FIG. 8 is a schematic view of the overall structure of a limiting mechanism in the composite dryer used in the present invention;

FIG. 9 is a schematic view of a retainer ring structure of the composite dryer used in the present invention;

FIG. 10 is a schematic view showing a structure of a swing lever in the composite dryer used in the present invention;

FIG. 11 is a schematic view of a material frame structure of the composite dryer used in the present invention;

FIG. 12 is a block diagram of an electric control system of the composite dryer used in the present invention;

FIG. 13 is a partial structural view of a composite dryer used in the present invention;

FIG. 14 is a schematic perspective view of a feeding device of the composite dryer used in the present invention;

fig. 15 is a schematic perspective view of a discharging device in the composite dryer used in the present invention.

Detailed Description

A pretreatment process for realizing efficient puffing and drying of areca nuts by combining superheated steam and microwaves comprises the following steps:

firstly, rehydrating dry areca nuts;

C. taking out and airing to obtain the rehydrated areca nuts;

as a further limitation of the invention, the rehydration solution in the step one is composed of water and sodium carbonate, and 2000-3000 parts of water and 10-20 parts of sodium carbonate are added into each 1000 parts of the dry betel nut in parts by weight.

Step two, swelling and sterilizing the areca nuts;

A. putting the rehydrated areca nuts into a compound dryer;

D. taking out to obtain the expanded areca nut;

as a further limitation of the invention, in the second step, when the areca nuts are expanded and sterilized, the stacking height of the areca nuts in the composite puffing machine is controlled to be 2-15cm, and the cavity breaking rate is controlled to be below 1%.

Firstly, the effect of the treatment by the superheated steam is rapid heat transfer, so that the temperature inside and outside of the betel nut is rapidly raised, the betel nut has the similar tempering and swelling effects, because the swelling depends on the movement of water molecules, the superheated steam efficiently penetrates through the betel nut, the movement of the water molecules is accelerated, the pressure difference between the inside and the outside of the betel nut is formed, the swelling effect is achieved, the microwave and the superheated steam are simultaneously treated, the microwave can accelerate the movement of the water molecules from inside to outside, the internal and external pressure difference is instantly changed, the swelling is promoted, the inside and the outside of the swelled betel nut are uniformly heated, and the quality is better.

Step three, performing biological enzymolysis on the areca nuts for flavoring;

A. filling the swelled areca nuts into a flavoring tank, and pouring the compound softening enzyme liquid, the feed liquid and the water into the flavoring tank;

As a further limitation of the invention, in the third step, the feed liquid comprises the following components in parts by weight: 5-8 parts of sodium cyclamate, 30-50 parts of white sugar, 1-2 parts of aspartame, 3-5 parts of saccharin, 1-3 parts of salt, 8-10 parts of orange oil and 250 parts of water 150-.

Step four, baking and drying the areca nuts;

Then, the preparation of the betel nut also involves the process flows of stuffiness, seed pressing, surface beating, glue drying, seed cutting, kernel removing, brine adding, packaging and the like, and the processes adopt the prior art and are not within the protection scope of the patent, and are not repeated herein.

Best embodiment 1, the steps are as follows:

firstly, rehydrating dry areca nuts;

A. filling the betel nut dried fruits subjected to impurity removal and grading screening into a brewing tank;

B. preparing rehydration feed liquid, and pouring the rehydration feed liquid into a brewing tank; the rehydration liquid consists of water and sodium carbonate, and 2000 parts of water and 15 parts of sodium carbonate are added into every 1000 parts of the areca nut dry fruit according to the parts by weight.

C. Setting operation conditions for rehydration, wherein the temperature is 25 ℃, the time is 12 hours, and the rotating speed rotates 2.5 circles per hour;

D. taking out and airing to obtain the areca nuts after rehydration; the water content of the areca nut before rehydration is controlled at 10%, and the water content of the obtained areca nut after rehydration is controlled at 34%.

Step two, swelling and sterilizing the areca nuts;

A. putting the rehydrated areca nuts into a compound dryer;

B. performing superheated steam treatment on the areca nuts, wherein the steam pressure is 0.4MPa and the superheated steam temperature is 160 ℃;

C. after the superheated steam treatment is carried out for 2 minutes, the microwave treatment is added to the areca nuts while the superheated steam treatment is continued, the microwave frequency is set to be 2450 +/-15 MHZ, the power is set to be 400w, and the time is 2 minutes; the stacking height of the areca nuts in the composite puffing machine is 2-15 cm.

D. Taking out to obtain the expanded areca nut;

step three, performing biological enzymolysis on the areca nuts for flavoring;

A. filling the swelled areca nuts into a flavoring tank;

B. preparing compound softening enzyme liquid and feed liquid, pouring the compound softening enzyme liquid and the feed liquid into a flavoring tank, and adding 3 parts of the compound softening enzyme liquid, 50 parts of water and 1 part of the feed liquid into each 1000 parts of the dry areca nuts;

the compound softening enzyme comprises the following components in parts by weight: 1 part of cellulase, 0.8 part of xylanase, 0.4 part of glucanase and 0.3 part of mannase. The feed liquid comprises the following components in parts by weight: 8 parts of sodium cyclamate, 30 parts of white sugar, 2 parts of aspartame, 4 parts of saccharin, 2 parts of salt, 10 parts of orange oil and 200 parts of water.

C. Setting operation conditions for enzymolysis and flavoring, wherein the temperature is 55 ℃, the time is 36 hours, and the rotation speed is 2.5 circles every 40 minutes;

D. taking out to obtain areca nuts after being subjected to enzymolysis and flavoring;

step four, baking and drying the areca nuts;

A. placing the flavored Arecae semen fruit subjected to enzymolysis into a composite dryer, and performing superheated steam and microwave synchronous treatment, wherein the stacking height of Arecae semen fruit is 2-15 cm. The working conditions are as follows: setting the steam pressure of 0.4MPa, the superheated steam temperature of 160 ℃, the microwave frequency of 2450 +/-15 MHz and the power of 280w, and combining the drying treatment time for 5 minutes;

B. putting the areca nuts dried by the combination of superheated steam and microwave into an oven, and drying by hot air at 80 ℃ until the moisture content is 19.5%.

As shown in fig. 1, a composite dryer is used in the process of the present invention, and comprises a composite drying device 2, a feeding device 1 and a discharging device 3 which are arranged at two sides of the composite drying device 2 and are responsible for material transportation, and an electric control system 4;

as shown in fig. 4-5, the composite drying device 2 is provided with a material chamber 319 in the middle of the main frame 37, and the material chamber is a closed space formed by a left heat-insulating protective layer 36, a right heat-insulating protective layer 36, a front safety door 317, a rear safety door 317, a bottom plate 318 and a top plate 321. Two magnetrons 34 and a microwave generator 32 are respectively arranged above a top plate 321 of the material chamber 319, and microwaves are generated through the combined action of the microwave generator and the magnetrons; a through hole is formed in the center of the top plate 321, the through hole is communicated with a fan 31 located at the top of the main frame 37 through an exhaust pipeline 323, and water evaporated during baking in the material chamber can be pumped away through the fan; two sides of the top plate are respectively provided with a heating tube for illuminating the material chamber, thereby facilitating observation. A plurality of air guide holes are uniformly distributed on a bottom plate 318 of the material chamber 319, a flow guide cover 322 is arranged under the bottom plate, the flow guide cover is an arc-shaped cover, on one hand, the generation of turbulent flow can be reduced, on the other hand, the flow guide cover can be used as a temporary buffer storage space, superheated steam can uniformly enter the material chamber through small holes of the bottom plate after entering the flow guide cover, and in addition, a flange plate 323 is opened, and residues left by internal materials can be cleaned; the front and back directions of the material chamber 319 are respectively provided with a safety door 317 opened and closed by a safety door cylinder 316, the two safety doors 317 are respectively communicated with the conveying rollers of the feeding device 1 and the discharging device 3, materials enter and exit from the conveying rollers, and the opening or closing of the doors can be controlled by the cylinders.

A steam generator 310 is installed on one side of the bottom of the main frame 37 and used for generating steam, a superheated steam generator 313 is installed on the other side of the bottom of the main frame and used for continuously heating the steam to generate superheated steam, the steam generator and the superheated steam generator are integrated by adopting mature equipment in the current market, a complete and independent steam production system and a superheated steam production system are arranged in the superheated steam generator, and a user only needs to be electrified by water and meanwhile accesses a corresponding control signal to a PLC. The steam generator 310 is connected with the superheated steam generator 313 through a pipeline, and the superheated steam generator 313 is connected with the air guide sleeve 322 through a pipeline.

A third manual valve 311 (capable of controlling the flow of steam), a flow meter 312 (capable of monitoring the current steam flow in real time) and a drain valve 314 (capable of filtering condensed water) are arranged on a pipeline between the steam generator 310 and the superheated steam generator 313; a second manual valve 38 (capable of controlling the flow of the superheated steam) and a temperature sensor 39 (capable of measuring the temperature of the superheated steam) are installed on a pipeline between the superheated steam generator 313 and the air guide sleeve 322, so as to feed back the temperature to the PLC, and the PLC controls the superheated steam generator 313 to reach the required target temperature. A manual valve 33 is mounted on the exhaust pipe 323 between the material chamber 319 and the fan 31.

Parts such as pipelines, valves, air guide sleeves and the like which are internally provided with heat conduction in the composite drying device are wrapped by heat-insulating cotton, so that heat loss is reduced.

As shown in fig. 2-3 and 6-7, the feeding device 1 and the discharging device 3 are both provided with a plurality of rollers 12 driven by a motor 14 above a frame 11, and the rollers 12 convey material frames 6; the guide strips 13 are arranged on the inner side edges of the frame 11 on the two sides of the roller 12, and the balls are uniformly distributed on the guide strips 13, so that the material frame 6 can be prevented from deviating, and the friction force can be reduced.

The feeding device 1 is provided with a blocking cylinder 15 below a frame 11 close to one side of the composite drying device, and is used for blocking the material frame to advance, wherein the blocking cylinder 15 is hidden below a roller 12 and is higher than a roller conveying surface when receiving a blocking instruction; two propulsion cylinders 16 are arranged on a cylinder mounting plate 24 above the frame 11 side by side, a connecting rod 23 is connected between cylinder piston rods of the two propulsion cylinders 16, and two ends of the connecting rod 23 are respectively provided with a group of limiting mechanisms 5; the connecting rod 23 can realize synchronous advance and retreat of the air cylinder, and the layout is also favorable for ensuring the stability during pushing.

The cylinder mounting plate 24 is arranged above the rack close to one side of the composite drying device of the discharging device 3, the two discharging cylinders 49 are arranged on the cylinder mounting plate 24 side by side, the connecting rod 23 is connected between the cylinder piston rods of the two discharging cylinders 49, and the middle section of the connecting rod 23 is provided with a group of limiting mechanisms 5.

As shown in fig. 8-10, the limiting mechanism 5 includes two fixing rings 51 and a swing rod 52 engaged between the two fixing rings 51, the fixing rings 51 are located at two sides and fixed on the connecting rod 23, and the end surface of the inner side of the fixing ring 51 is provided with a notch 53; the swing rod 52 is composed of an annular head 54 and a swing arm 55, the swing arm 55 is divided into a straight arm and a bent arm, the annular head 54 is movably arranged on the connecting rod 23, and two end faces of the annular head 54 are respectively provided with a lug 56 meshed with the notch 53.

As shown in fig. 14, in the feeding device 1, the fixed ring 51 and the swing lever 52 (adopting a bent arm structure) in the limit mechanism 5 are both mounted with the connecting rod 12 as an axis, and the fixed ring 51 can swing the swing lever 52 at a fixed angle, the initial state is vertical downward, and the swing direction is counterclockwise 90 degrees. When the material frame 6 passes under the swing rod 52, the push rod can swing (anticlockwise) along the advancing direction of the material frame, when the material frame completely passes through the swing rod 52, the push rod returns to the vertical state, and when the pushing cylinder 16 extends to push the material, the swing rod 52 side is stressed reversely and is in the limiting position, so that the material frame is pushed away.

As shown in fig. 15, in the discharging device 3, the fixed ring 51 can make the swinging rod 52 (adopting a straight arm structure) swing at a fixed angle, the initial state is vertical downward, and the swinging direction is counterclockwise 90 degrees. When the 2.1 material frame passes under the swinging rod 52, the push rod can swing (anticlockwise) along the advancing direction of the material frame, when the material frame completely passes through the swinging rod 52, the push rod returns to the vertical state, and when the discharging air cylinder 49 extends to pull the material, the swinging rod 52 side is stressed reversely and is in a limiting position, so that the material frame is pulled away.

As shown in fig. 11, the material frame 6 is made of polytetrafluoroethylene, and is suitable for a microwave environment, and vent holes 61 are uniformly formed in the bottom of the material frame, so that superheated steam can pass through the material frame conveniently to bake the material. Handles 62 convenient to take manually are arranged at two ends of the frame, and a waist hole 63 is formed in each handle and is convenient for the discharging cylinder to pull out the material frame.

As shown in fig. 12, the electronic control system 4 includes the following sensors distributed in various positions of the device:

a third cylinder sensor 315 is arranged on a safety door cylinder 316 of the material chamber 319 in the composite drying device 2; a temperature sensor 39 is arranged on a pipeline between the superheated steam generator 313 and the air guide sleeve 322;

a first cylinder sensor 19 and a second cylinder sensor 20 are respectively arranged at two ends of a propulsion cylinder 16 of the feeding device 1, and a blocking sensor 18 is arranged below the rack 11 close to one side of the composite drying device;

a four-cylinder sensor 46 and a five-cylinder sensor 48 are respectively arranged at two ends of a discharging cylinder 49 of the discharging device 3, and a discharging sensor 410 is arranged on the outer side of the rack near the cylinder mounting plate 24;

the device further comprises a PLC, the sensors are respectively connected with the PLC, and the PLC is connected with the control motor 14, the propulsion cylinder 16, the discharging cylinder 49, the fan 31, the steam generator 310, the superheated steam generator 313, the safety door cylinder 316 and the blocking cylinder 15.

The working process of the invention is as follows, with reference to fig. 13-15:

after the equipment is powered on, the parameters are called or reset on the human-computer interface. When the device is started for the first time, the steam generator and the superheated steam generator are started, the fan is started, the corresponding valve is opened, superheated steam enters the material chamber, and the feeding conveying line is started after the temperature in the material chamber reaches a set temperature.

Feeding: the material (areca nut) is uniformly spread in the material frame manually or by equipment, then the material is placed on the conveying line roller, the material is conveyed forwards continuously by the conveying line, when the blocking sensor senses the material frame, the blocking cylinder acts (the initial state is blocking), the material frame normally advances, when the material frame leaves the blocking sensor, the blocking cylinder restores the blocking state, and the material frame behind is blocked. When the blocking sensor senses the material frame, the safety door cylinders in front of and behind the composite drying device act to open the safety door, the material frame in front of the composite drying device enters the material chamber along the guide plate, the material chamber is unpowered, the pushing cylinder pushes the material frame into the material chamber completely, the pushing cylinder returns to the initial position, then the safety door cylinder resets, the safety door is closed, and the material begins to be baked according to the process setting. During baking, water vapor emitted by the material can be pumped away by the fan, and the change condition of the material can be observed by naked eyes through the peeping window on the heat-insulating protective layer.

Discharging: after baking is finished, starting a discharging device, starting a motor and operating a roller; the safety door cylinder acts to open the safety door, and the discharging cylinder extends into the material chamber to pull out the material frame. After the material frame is pulled out, the emergency exit cylinder moves and resets, and ejection of compact sensor has also detected the material frame simultaneously, just this moment calculates the completion ejection of compact. After the material frame enters the roller line, the material frame is slowly conveyed to the next working procedure. In order to save time and ensure that the heat in the material chamber is reduced and dissipated as much as possible, feeding is carried out simultaneously when discharging after the baking is finished, and the feeding mode is the same as the feeding mode, so that the circulation is carried out until the baking is finished.

Claims

1. A pretreatment process for realizing efficient puffing and drying of areca nuts by combining superheated steam and microwaves is characterized by comprising the following steps:

firstly, rehydrating dry areca nuts;

C. taking out and airing to obtain the areca nuts after rehydration;

step two, swelling and sterilizing the areca nuts;

A. putting the rehydrated areca nuts into a compound dryer;

C. after the superheated steam treatment is carried out for 1-3 minutes, the microwave treatment is added to the areca nuts while the superheated steam treatment is continued, the microwave frequency is 2450 +/-15 MHZ, the power is 280-960w, and the time is 0.5-6 minutes;

D. taking out to obtain the expanded areca nut;

step three, performing biological enzymolysis on the areca nuts for flavoring;

B. setting operation conditions for enzymolysis and flavoring, wherein the temperature is 50-60 ℃, the time is 36-48 hours, and the rotating speed is 2-5 circles every half hour;

step four, baking and drying the areca nuts;

2. The pretreatment process for realizing efficient puffing and drying of betel nuts by combining superheated steam and microwaves as claimed in claim 1, wherein the pretreatment process comprises the following steps: the rehydration liquid in the step one is composed of water and sodium carbonate, and 2000 portions of 3000 portions of water and 10-20 portions of sodium carbonate are added into every 1000 portions of the dry areca nuts according to the weight portion ratio.

3. The pretreatment process for realizing efficient puffing and drying of betel nuts by combining superheated steam and microwaves as claimed in claim 1, wherein the pretreatment process comprises the following steps: in the areca nut rehydration process in the first step, the moisture value of the areca nut before rehydration is controlled to be 8-17%, and the moisture value of the obtained areca nut after rehydration is controlled to be 30-36%.

4. The pretreatment process for realizing efficient puffing and drying of betel nuts by combining superheated steam and microwaves as claimed in claim 1, wherein the pretreatment process comprises the following steps: and in the second step, when the areca nuts are expanded and sterilized, the stacking height of the areca nuts in the composite puffing machine is controlled to be 2-15cm, and the cavity breaking rate is controlled to be below 1%.

5. The pretreatment process for realizing efficient puffing and drying of betel nuts by combining superheated steam and microwaves as claimed in claim 1, wherein the pretreatment process comprises the following steps: in the third step, 2-6 parts of compound softening enzyme liquid, 50-100 parts of water and 1 part of feed liquid are added into each 1000 parts of dry areca nuts.

6. The pretreatment process for realizing efficient puffing and drying of betel nuts by combining superheated steam and microwaves as claimed in claim 1 or 5, wherein the pretreatment process comprises the following steps: in the third step, the composite softening enzyme comprises the following components in parts by weight: 0.5-1.5 parts of cellulase, 0.5-1.5 parts of xylanase, 0.25-1 part of glucanase and 0.2-1 part of mannase.

7. The pretreatment process for realizing efficient puffing and drying of betel nuts by combining superheated steam and microwaves as claimed in claim 1 or 5, wherein the pretreatment process comprises the following steps: in the third step, the feed liquid comprises the following components in parts by weight: 5-8 parts of sodium cyclamate, 30-50 parts of white sugar, 1-2 parts of aspartame, 3-5 parts of saccharin, 1-3 parts of salt, 8-10 parts of orange oil and 250 parts of water 150-.

8. The pretreatment process for realizing efficient puffing and drying of betel nuts by combining superheated steam and microwaves as claimed in claim 1, wherein the pretreatment process comprises the following steps: in the fourth step, when the areca nuts are baked and dried, the stacking height of the areca nuts in the composite puffing machine is controlled to be 2-15cm, the cavity breaking rate is controlled to be below 2%, and the moisture value after hot air drying at 80 ℃ is controlled to be 18-21%.