In the food industry, modified atmosphere packaging is increasingly being used to extend the shelf life of products. This technology is widely used in the dairy sector, particularly for milk powder products that contain unsaturated fats. The main goal is to slow down or prevent the oxidation of fats.
Fat oxidation occurs in the presence of oxygen. By reducing the oxygen content inside the product or packaging, this process can be significantly slowed down. In most cases, the oxygen is replaced by nitrogen or a mixture of nitrogen and carbon dioxide.
The oxygen concentration can be reduced by purging the product with a gas or gas mixture that contains no oxygen. A highly effective method involves first removing the oxygen using vacuum technology. After this evacuation step, the product is purged or flushed with an inert gas, typically nitrogen. Nitrogen is introduced into the powder until the packaging has returned to normal atmospheric pressure.
The theoretical relationship between the vacuum level achieved and the remaining oxygen content is shown in the following table.
Poeth Solids Processing has developed a turnkey solution for evacuating and nitrogen-flushing filled big bags. The system is activated after the big bag has been filled, meaning it operates independently of the filling station.
The system performs the entire process automatically, including sealing.
