Wholesale supply of liquid nitrogen quick freezing machines

Utilization of Tunnel style Liquid Nitrogen Freezing MachineLiquid nitrogen is used as a refrigerant to directly freeze food. The principle of liquid nitrogen freezing is to spray low-temperature liquid nitrogen directly onto the food and use it to vaporize under normal pressureExtremely lowtemperatureThe high heat transfer coefficient of (-196 ℃) and direct vaporization on the surface of the material quickly and deeply freezes the food. It has been widely used in various types of food.

Chengdu Zhuoda YuntongLiquid nitrogen quick freezing machine is tunnel type, insulation board is polyurethane foam insulation layer, double-sided stainless steel panel, material transmission is stainless steel mesh belt, driven by speed regulating motor, equipment liftingoptionalIt can be raised during maintenance and cleaning. The tunnel consists of a pre cooling section, a spraying section, and a temperature equalization section. The pre cooling section is mainly used to moderately pre cool the material, in order to fully utilize the sensible heat after liquid nitrogen vaporization and avoid excessive temperature difference during deep freezing, which may cause cracks in thicker materials; The spray section is a rapid freezing process in which liquid droplets are directly sprayed onto the surface of the material through a nozzle under the pressure of a liquid nitrogen tank. The temperature equalization section ensures that the surface of the material is not affectedcompleteThe vaporized droplets are fully vaporized. The vaporized low-temperature nitrogen is extracted by the exhaust fan, and the material is stirred with low-temperature nitrogen on the stainless steel mesh belt by the fan and sucked by the exhaust fan for countercurrent heat exchange.Quick freeze 1kg of food, with a liquid nitrogen consumption of 0.6-1.5Between kg, it varies depending on the type and size of the material. Nitrogen content in the air is 75%, and liquid nitrogen is generally a byproduct of oxygen production. After gasification, it is reduced to the atmosphere and has no pollution to the environment. Due to the short freezing time and mainly relying on direct vaporization and heat exchange of liquid nitrogen, the drying consumption of frozen products is much lower than that of air cooling methods. At present, liquid nitrogen freezing method has been widely used in various fields such as seafood, whole fish, meat patties, segmented meat, pies, hamburgers, as well as ice cream hardening.

Why choose liquid nitrogen as the refrigerant?

Why choose liquid nitrogen as the refrigerant? liquid nitrogenenvironment protectionIt is a colorless, transparent, and low viscosity liquid. Liquid nitrogen has stable chemical properties and its boiling point at atmospheric pressure is-At 196.5 ℃, it does not undergo chemical reactions with frozen products and is inert to food ingredients. Liquid nitrogen meets food hygiene requirements and is an ideal food preservative. The nitrogen content in the air is 78%, making it an inexhaustible and environmentally friendly refrigerant. Furthermore, by replacing the air that comes out of food, oxidation changes can be reduced during freezing and packaging storagemoreSmall limit.
At standard atmospheric pressure, when liquid nitrogen absorbs heat and undergoes a phase transition to a gaseous state, it needs to absorb 199.29 KJ/KG of latent heat of vaporization, and then the low-temperature gas rising from -196.5 ℃ to -10 ℃ needs to absorb 202 KJ/KG of heat. Liquid nitrogen utilizes thisvery lowThe temperature absorption characteristic is used for rapid cooling, with a temperature difference of up toAbove 200 ℃, strong heat exchange can cause frozen products to freeze instantly, forming a hard shell on the surface. The moisture inside the frozen products will not evaporate, resulting in a high drying rateveryLow, almost zero. Due to freezing timeveryShort,5 to 10 minutes, which is 1/8 to 1/5 of the conventional freezing method. The ice crystals generated inside the frozen product are very fine and uniform, and the freezing speed is greater than the permeation speed of steam inside and outside the cell. Ice crystals are generated both inside and outside the cell, without damaging the cell wall. Therefore, after thawing, the original color, aroma, taste, and freshness of the frozen product can be maintained. Liquid nitrogen quick freezing is currently the most effective methodRelatively XianjinOne of the fast freezing and preservation techniques for food.