Instant noodle freeze-drying machine

Instant noodle freeze-drying machineVacuum freeze-drying is a food dehydration process. Compared with commonly used hot air drying methods, products processed with this method have long shelf life, good rehydration properties, and excellent color, aroma, taste, and nutrition. The volume and shape of the freeze-dried product remain basically unchanged, with a sponge like substance and no drying shrinkage phenomenon. It can be applied to various food industries, such as fruits, vegetables, seasonings, aquatic products, seafood, biological products, beverages, specimens, and other fields. Delicious and colorful, with high nutritional value, and conducive to long-term preservation.

The so-called vacuum freeze-drying is a drying method that involves pre treating a substance containing water, rapidly freezing it at -30 ℃ and creating a vacuum environment to sublime the water from a solid state to a gaseous state, in order to remove the water and preserve the substance.

The vacuum freeze-drying equipment is a series of single freeze-drying equipment with an area ranging from 0.5m2 to 280m2 that our company has developed. Our customers are located in Zhejiang, Henan, Yunnan, Shandong, Fujian, Hainan, Hubei and other provinces, and our equipment is operating well. Our freeze-dried food meets the quality export standards.
Vacuum freeze-drying equipment mainly includes: food pre freezing system, drying chamber system, heating system, vacuum system, refrigeration system, material conveying system, media system, pneumatic system, cleaning system

Two working principles

Vacuum freeze-drying is a drying method that involves pre treating a substance containing water, rapidly freezing it at -30 ℃, and creating a vacuum environment to sublime the water from a solid state to a gaseous state, in order to remove the water and preserve the substance.

Vacuum freeze-drying equipment mainly includes: food pre freezing system, freeze-drying tank, heating system, vacuum system, refrigeration system, material conveying system, and monitoring system.

The FD series production freeze-drying equipment is divided into 50, 75, 100, 150, and 200 according to the nominal area of the heating plate? 1?71? The main difference between different specifications such as 1-77O lies in the length of the drying chamber and the number of material pulleys that can be loaded, ranging from 2 to 8 per chamber.

Composition of Three Vacuum Freeze Drying Equipment

This machine is mainly composed of six components: drying oven, condenser (water trap), heating system, vacuum system, refrigeration system, and electrical control system.

1 drying oven
It is a sealed container capable of vacuuming and heating. The sublimation drying process of materials is completed in the drying chamber. The materials are placed on stainless steel trays on the shelves in the drying chamber, and are loaded in a ratio of 8-12 kilograms per square tray area. Each shelf has a probe for measuring the temperature of the materials to monitor the temperature of the entire freeze-drying process. The door adopts rubber sealing strips, and attention should be paid to tightening the handle on the door and sealing the box when closing it.

2 Condenser (water trap)
It is a closed device for condensing and sublimating water vapor. There is a large area of metal adsorption surface inside, and the water vapor sublimated from the drying oven material can condense and adsorb on its metal surface. The working temperature of the adsorption surface can reach -45 ℃~-55 ℃. The condenser is made of stainless steel or iron cylindrical shape, and there are condenser tubes inside, which are connected to the refrigeration unit to form a refrigeration cycle system. The condenser is connected to the drying oven using a vacuum butterfly valve; The vacuum system is composed of stainless steel pipes connected to a vacuum pump unit. The upper part of the condenser pipe in the cylinder is equipped with a defrosting spray pipe, which is connected to the water pipe through a vacuum diaphragm valve to prevent defrosting water and other substances from entering the drying oven and vacuum pipeline. Foam plastic plate is used outside the condenser for thermal insulation, and stainless steel plate is used as the outer layer.

3 Heating system
The function of the freeze-drying machine heating system is to heat the materials inside the drying oven, so that the materials can continuously obtain sublimation heat, and the items can meet the specified moisture content requirements. There are different heating methods for the freeze-drying machine heating system, and in contact heating, we use the circulating medium heating method. The circulating heating system consists of pipeline pumps, circulating medium tanks, heaters, inlet and outlet pipelines, liquid temperature controllers, etc. The circulating liquid is composed of 4 parts of water, 2 parts of ethanol, and 4 parts of ethylene glycol to form a circulating non freezing liquid. Its freezing point is -120 ℃, and the liquid temperature does not exceed 60 ℃ during use. When the heating system is working, the circulating liquid is first heated, and the liquid temperature is automatically controlled by the temperature selected by the liquid box control regulator. After the pipeline pump is turned on, the circulating liquid can be sent to the shelf in the drying box to heat the shelf, and then returned to the liquid box for heating circulation. In radiation or heating, we use steam heating with a high temperature of 120 ℃, which is automatically controlled by a steam solenoid valve.

4 Vacuum system
The vacuum system consists of a rotary vane vacuum pump or water ring pump and a Roots vacuum pump. The Roots pump is a booster pump and cannot be used alone. Start the rotary vane pump or water ring pump and let it work for a period of time. When the vacuum degree in the system reaches below 1Kpa, the Roots pump will automatically start. Please refer to the instruction manual for the structure of the rotary vane pump and Roots pump. The vacuum gauge of this vacuum system can use an electric contact vacuum gauge, which can automatically control the start of the Roots pump based on the pre selected vacuum degree value. There is a vacuum butterfly valve installed in the vacuum pipeline between the drying oven and the condenser, which can be opened and closed according to usage requirements. On the vacuum pump pipeline, an electromagnetic vent shut-off valve is installed. When the vacuum pump stops working, the vacuum pipeline can be automatically closed, and air can be put into the pump. The vacuum pump oil is replayed into the vacuum pipeline due to negative pressure. A corrugated hose is installed between the connecting pipelines of the vacuum pump to prevent vibration during operation.

5 Refrigeration System
The freeze-drying refrigeration system consists of a refrigeration compressor unit (including a water-cooled condenser, an oil separator, a high-pressure pipeline, a drying filter, an expansion valve, an evaporator, and a low-pressure pipeline), using a Freon unit and R22 refrigerant or fluorine refrigeration unit. The refrigeration unit consists of a refrigeration system for quick freezing of freeze-dried products and a water trap refrigeration system. When the system is working, the temperature of the shelf in the contact heating mode can be reduced to -35 ℃. When the refrigeration system is working, the surface temperature of the condensing coil can reach -35 to -55 ℃. Single stage or two-stage refrigeration compressor units can be used according to customer needs for good refrigeration.

6 Electrical Control System
The electrical control system of this equipment consists of automatic devices and circuits such as computer display recorders, control consoles, control instruments, and regulating instruments. Its function is to manually or automatically control the freeze-drying machine and ensure the normal operation of the equipment.
The control panel is a centralized group of recording and control instruments for temperature and vacuum inspection instruments, as well as switches for each unit. The dashboard of the control panel is equipped with temperature and vacuum inspection instruments, vacuum gauges for drying ovens and vacuum pumps, temperature indicator regulators, liquid temperature control regulators, timing clocks, etc. The button board is equipped with switches for each unit. The freeze-drying machine is also equipped with a chain protection device, such as ① the heating tube cannot work when the front box is cooled; ② The vacuum gauge does not reach the set value, and the Roots pump cannot start. ③ Cooling water is not provided, and the refrigeration unit does not start. ④ The vacuum pump, solenoid valve with air release shut-off valve, and vacuum pump power meter are connected together and work simultaneously. ⑤ The shelf is heated at a constant temperature and controlled by a temperature indicator regulator.

Four freeze drying equipment

Freeze drying is the process of removing moisture from frozen materials and products. Freeze drying is divided into two types: vacuum freeze-drying and atmospheric freeze-drying. Due to some limitations, vacuum freeze-drying is currently used. The purpose of freeze-drying is to preserve the complete biological and chemical structure and activity of the product. Like many other steps, a type of freeze-drying is called sublimation and occurs naturally. Sublimation refers to the process in which a solvent, such as water, like dry ice, directly changes from a solid state to a gaseous state. Traditional drying can cause material shrinkage and damage cells. This situation will not occur during freeze-drying, as the solid composition is supported by solid ice in its position. When ice sublimates, it leaves pores in the remaining dry material.

The freeze-drying process is divided into three stages: freezing, sublimation, and analytical drying. Each stage has corresponding requirements, and different materials have different requirements. The differences in process design and control methods in each stage directly affect the quality of freeze-dried products and the performance of freeze-drying equipment.

1. Freezing stage

Freeze drying involves freezing the raw materials to turn the water in them into ice, preparing them for the next stage of sublimation. The freezing temperature and freezing speed are the control objectives, and the temperature should reach below the freezing point of the material. Different materials have different freezing points. The speed of freezing is directly related to the size of ice crystal particles in the material, and the size of ice crystal particles is directly related to the structure and sublimation rate of solid materials. Generally, it takes 1-3 hours to complete the freezing of the material and enter the sublimation stage.

2. Sublimation stage

Sublimation drying is the main process of freeze-drying, which aims to vaporize and remove ice from the material. The entire process does not allow the ice to melt, otherwise it will result in freeze-drying failure. The two basic conditions for sublimation are: first, ice does not melt; The second is that the water vapor around the ice is below 610 Pa (the correct statement should be the saturated vapor pressure below the freezing point of the material). Sublimation drying requires continuous removal of water vapor to keep the water vapor pressure below the required saturation vapor pressure. On the other hand, in order to accelerate the drying speed, it is necessary to continuously provide the heat required to maintain sublimation. This requires optimized control of water vapor pressure and heating temperature, so that sublimation drying can be completed quickly and with low energy consumption.

3. Analyze drying

After the sublimation and drying of ice crystals in the material, many voids are left inside the material, but there is still residual unfrozen water in the matrix of the material (which exists in the form of bound water and glassy state). Drying analysis is to remove residual unfrozen moisture and obtain dried materials.