Rotary vane vacuum pump in food processing application
Rotary vane vacuum pump this pump product is not unfamiliar to everyone, but for the real understanding of the vacuum pump is in a few, vacuum pump has many functions, in the fruit and vegetable preservation and cooked food processing vacuum pump in this area is also quite extensive application.
The ideal cooling method that meets the following requirements is vacuum cooling.
1, fruits and vegetables harvested after harvest are still living individuals. Essential substances and energy are obtained through respiration. Breathing, on the one hand, maintains the life of individuals, but on the other hand consumes stored substances. As a result, fruits and vegetables began to age. The purpose of preservation is to delay aging, so it is necessary to control breathing, and the most closely related factor with breathing is temperature. Respiration releases both energy and temperature. In turn, it promotes respiration and accelerates the senescence of fruits and vegetables. Obviously, if the temperature of fruit and vegetable can be lowered, the respiration can be effectively controlled and the senescence can be delayed. Therefore, the fruit and vegetable must be pre-cooled after harvesting, as soon as possible to remove heat in the field, reduce respiratory heat. It creates conditions for prolonging freshness. At present, natural cooling method is generally used to cool, which covers a large area and takes a long time. It is not only difficult to meet the requirements of rapid pre-cooling, but also unsuitable for industrial production. Some of them are put directly into the cold storage for cooling, which is unreasonable and uneconomical, and can not be cooled quickly and evenly.
2. Cooked food must be cooled before packaging. Traditional cooling methods include natural cooling, forced ventilation cooling, air conditioning room cooling, cold storage cooling and so on. These cooling methods not only have a long cooling time (several to ten hours), slow turnover, occupy a lot of land, but also have uneven cooling, large temperature difference between the surface and the center, and more importantly, affect food hygiene and safety. During the cooling process, the bacteria in the air will inevitably stick to the food and cause "secondary pollution" of the food, especially between 50 and 25 degrees Celsius, which is the high-speed breeding area of bacteria. Rapid passing through this temperature range can greatly reduce the generations of bacteria reproduction, easy to control the amount of original bacteria, which is conducive to increasing food intake. Product safety and extend shelf life. This is of great significance for the implementation of the "Food Safety Law", which shows that the food processing industry also needs an advanced method and equipment for rapid cooling.
Various vacuum acquisition techniques and corresponding vacuum cooling equipment
1, rotary vane vacuum pump, water trap combination system and fruit and vegetable vacuum pre Cooler:
Rotary vane vacuum pump is one of the most basic vacuum equipment in vacuum technology. This is an oil-sealed mechanical vacuum pump with large pumping speed, small volume, high limit vacuum and low noise. In this vacuum pump, oil plays an important role. It has three functions of sealing, lubrication and cooling.
The principle of vacuum cooling is to cool itself by absorbing moisture when vaporizing water. Therefore, water vapor will be produced in the cooling process. If water vapor enters the rotary vane pump directly, it will cause the emulsification of the pump oil, which will not only affect the performance of the pump but also damage the pump itself. The solution is to add a water catcher in front of the pump and use the low temperature to condense the water vapor into water and discharge it. For this reason, the refrigeration system must be reconfigured, and the water vapor is removed and then discharged by vacuum pump.
SV Series Rotary Vane Vacuum Pump
Fruit and vegetable vacuum pre-cooler is generally designed and manufactured according to the above principles, and its basic components are vacuum box, water catcher, refrigeration unit and rotary vane vacuum pump.
2. Water jet vacuum technology and normal temperature vacuum refrigerator:
Cooked food is different from the pre-cooling of fruits and vegetables, the initial temperature is very high, generally more than 90 degrees Celsius, cooling process will have a large amount of water vapor escape, therefore, if the use of rotary vane vacuum pump, water catcher combination system, water catcher and refrigeration unit must be matched very large, not only the unit is huge and high energy consumption, very little Economics. If the water jet vacuum technology is applied to cooked foods, the cooling effect is very good.
The technology integrates three functions of vacuum, condensation and drainage. It uses a certain pressure of water, symmetrically distributed into a certain inclination of the nozzle high-speed ejection, convergence in a focus, and then around the formation of negative pressure, so that the vacuum chamber connected with it produces a vacuum. In addition, due to the direct contact between steam and jet water, heat exchange, most of the steam condensed into water, through the diffuser is eliminated, the volume is greatly reduced, thus further forming a higher vacuum.