In the granule packaging industry, packaging quality directly determines product shelf life, transportation safety, and market competitiveness. Vacuum degree, sealing temperature, and shaping time are exactly the three core parameters that control packaging quality. Many enterprises often encounter problems such as sealing leakage, product oxidation and deterioration, and packaging deformation or damage due to improper parameter selection. Mastering the selection logic of these three parameters is the key to improving packaging quality.
Vacuum degree is the foundation of "freshness preservation" for granule packaging, which needs to be precisely adjusted according to the characteristics of granules. For common grains, cereals, and dried goods, a standard vacuum degree of -0.09 MPa can be adopted to effectively isolate oxygen and prevent mildew. For fragile granules such as puffed food, a "low-pressure slow pumping" method is required to avoid particle breakage caused by pressure. For granules containing trace moisture, the pumping rhythm must be controlled to prevent moisture boiling from affecting product quality. Excessive vacuuming tends to make the packaging bag cling tightly to the granules and cause damage, while insufficient vacuuming fails to achieve the freshness preservation effect.
Sealing temperature is directly related to the firmness of the seal, and the core is to match the characteristics of the packaging material. PE material packaging bags are suitable for a temperature range of 120–180℃; PP material requires a higher temperature of 140–200℃; composite films need 160–220℃. For thicker bags, the temperature should be increased accordingly or the sealing time extended, while for thinner bags, the temperature needs to be reduced to prevent melting through. Shaping time needs to balance appearance and efficiency: an overly long shaping time tends to cause particle caking, while an overly short time results in irregular packaging shapes that affect warehousing and stacking. Generally, it should be controlled within 2–5 seconds, and adjusted according to particle density and packaging specifications.
The selection of the three parameters must follow the principle of "coordinated matching" and cannot be adjusted in isolation. It is recommended that enterprises conduct small-batch tests based on particle types and packaging materials, and record the optimal parameter combination. Accurately controlling these three key parameters can not only avoid packaging losses, but also ensure stable product quality, laying a solid foundation for enterprises to enhance their core competitiveness.
