Vacuum packaging applications
With the rapid development of science and technology and the increasing demand for engineering technology, vacuum technology and various vacuum equipment should be used in scientific research and industrial fields.
Modern life is increasingly inseparable from vacuum technology.
We are inseparable from vacuum technology only from the field of food in our lives.
In order to prolong the shelf life and shelf life of food, the rice we eat must be vacuum-packed. The vegetables we eat need to be vacuum pre-cooled in the field, and then transported through the cold chain before they can be transported to cities farther away. Infant formula is freeze-dried under vacuum. The potato chips we eat are vacuum-fried in order to improve their nutrition and color, and the packaging bags are vacuum-coated to prevent moisture and oxygen from penetrating into the packaging, thereby increasing their shelf life.
The COVID2019 outbreak in Shanghai in the spring of 2022 made us realize the importance of food preservation and storage. The key to extending the shelf life of vegetables, fruits and meat products is to control temperature, moisture and atmosphere. Vacuum technology is critical in temperature, moisture, and atmosphere control. The main methods are: vacuum packaging, vacuum sealed storage, vacuum pre-cooling, vacuum body fitting, vacuum air-conditioned fresh-keeping packaging, and vacuum freeze-drying.
Vacuum packaging technology is to put the required items, especially food, into an airtight packaging container, usually a sealed plastic bag with a certain thickness and tear resistance, and then pass the air in the sealed container or plastic bag through a vacuum pump or a certain It is a packaging method that installs equipment to form a certain degree of vacuum and then seals it.
For food, any food has a certain number of microorganisms. These microorganisms will continue to multiply in the air due to the action of oxygen, resulting in the spoilage of food. However, when the oxygen concentration is less than 1%, the growth and reproduction rate of microorganisms will drop sharply. When the oxygen concentration is reduced to 0.5%, most bacteria will be inhibited and stop multiplying. In addition, the oxidation and discoloration of food are closely related to the oxygen content. For the oxidative deterioration of fatty products such as meat products, when the oxygen concentration is lower than 1%, the oxidation can also be effectively controlled. The vacuum packaging method is an effective packaging method to protect the quality of food and the like by causing low oxygen concentration conditions during packaging.
Vacuum packaging uses a vacuum pump to remove the gas in the container. When the vacuum degree reaches more than 98%, the residual air concentration is 2% of the atmospheric pressure, and the original oxygen concentration in the air is about 21%. It can be concluded that, When the vacuum degree reaches 98%, the concentration of oxygen is about 0.5% or less of the original atmospheric state. Therefore, for vacuum packaging, the required working pressure of the vacuum pump is 20hpa, so the required ultimate pressure of the vacuum pump is less than 2hpa. SRV single-stage rotary vane vacuum pump can be used. There is also no need to use a high-vacuum two-stage rotary vane vacuum pump or other high-vacuum vacuum pumps. Because if it is an oil-lubricated high vacuum pump, it will cause a small backflow phenomenon under higher vacuum. There is a certain potential risk of contamination of vacuum lines and chambers. Therefore, it is emphasized here that the use of SRV single-stage rotary vane vacuum pump for vacuum packaging is a cost-effective solution.
Foods suitable for vacuum packaging: rice, meat products, beans, etc.
Other items suitable for vacuum packaging: banknotes, important bills, documents, mechanical and electronic equipment products, clothing, etc.
Advantages of vacuum packaging:
1) Effectively inhibit oxidative deterioration and prolong the shelf life and shelf life of food.
2) Control moisture to prevent drying out.
3) Moisture-proof, mildew-proof, oxidation-proof, insect-proof, loss-proof, etc.
4) Through the pressure difference, the fluffy items can be compacted to form a certain shape, which is convenient for reducing space, storage and transportation.
5) Some foods can be further cooked at low temperature and preserved by modified atmosphere.
Small cavity type vacuum packaging machine is the ideal packaging choice for supermarket butcher shops, restaurants, hotels, retail stores, agricultural products stores and daily consumer goods. It can also be used for vacuum packaging of important documents, important documents and cash in households, companies and banks.