In the previous article, we learned about the "normal bulging" phenomenon of aluminum foil sealing film. Today, we will take a look at "abnormal bulging", which refers to the bulging that needs to be guarded against. 

This type of bulging usually indicates that the product quality may have changed or there may be packaging defects. 

1. Microbial decay and deterioration 

Reason: This is the most important reason to be vigilant. Due to incomplete sterilization during production or poor packaging sealing, microorganisms (such as yeast and bacteria) can grow inside the bottle. They reproduce extensively and metabolize to produce large amounts of gases (such as carbon dioxide and hydrogen), causing severe bulging. 

Characteristics: Bulges are usually very noticeable, hard, and may even cause deformation of the bottle body. Often accompanied by peculiar odor, rancid taste, cloudy liquid or sediment formation. Once such a situation is discovered, do not consume it. 

2. Gas production from chemical reactions 

Reason: Some chemical components in the product react with each other, or the product reacts with packaging materials (such as bottle cap liners) to generate gas. For example, the reaction between acidic substances and certain metallic substances produces hydrogen gas. 

Characteristic: Bulging may occur in specific batches of products and needs to be analyzed in conjunction with the product formula. 

3. Packaging process defects 

Reason: 

Poor sealing: Improper temperature, pressure, or time settings of the sealing machine result in incomplete fusion of the sealing film with the bottle mouth, creating small gaps and allowing external air to enter. 

Bottle mouth or film material issues: Uneven bottle mouth, stains, or uneven sealing film material can all affect the sealing effect. 

Characteristic: Bulging may be accompanied by leakage. 

Leadtra Packaging is a wholesale and customized manufacturer of aluminum foil sealing film, specializing in the research and development and production of various high barrier packaging materials and easy to tear sealing packaging materials. They are widely used in food, medicine, cosmetics, and daily necessities packaging, and have many advantages such as green environmental protection, high safety, strict testing, and stable quality. If you are interested in or have any questions about us, please feel free to call us for consultation.