Small leaks can lead to big problems for food manufacturers. When leaks are created in packaging process, this can mean expensive measures to fix the problem once products are despatched. Worse, if the leak goes undetected, this could result in product recalls for the company which ultimately damage the brand reputation. As a result, leak detectors are essential tools of the packaging process that make it possible to determine the quality of packaging in real-time. However, how is food package leakage detected?

 

In determining whether there is a leak, the package defect meets certain criteria in terms of the pressures generated with the packaging during distribution and the relationship between micro-organism characteristics and leak size.

 

Canned Goods


Contamination in canned foods can occur when micro-organisms pass through a seam in the container. This type of contamination is known as "leaker spoilage." Most researchers attribute can leaks to be the main source of post process contamination resulting in a loss of product sterility. Many of the food poisoning incidents can be associated with post process contamination due to leakage.

 

Flexible and Semi-Rigid Packaging


For flexible and semi-rigid packaging, package leaks may also occur. Flexible and semi-rigid packaging was originally developed as an alternative option to cans. These packages are generally made from polymers, metals and paperboard. Each layer is designed to offer specific strength and barrier features.

 

Leaks in flexible packaging occurs when the wrinkles in the seal area of the packaging contain holes or have food materials entrapped within the seals. In these cases, the seal contamination is the result of poor control over sealing parameters, problems with the mechanical alignment, and changes in the materials that make up the packaging which ultimately result in seal failure. Leaks can also occur when temporary holes appear in the material of the packaging. By setting hire standards for the material handling of these flexible and semi-rigid packages, pinholes can be avoided in many cases.

 

Flexible and semi-rigid packages may also be subject to other defects, including burst defects and seal creep. These problems can result from shock and vibration that occurs during product storage and distribution.

 

For flexible and semi-rigid packaging heat sealability and peelability are important for maintaining the sterility of these types of packaging. Sealing temperature, sealing pressure and dwell time must occur at specific material dependent temperature ranges in order to ensure that an adequate seal is obtained. Careful control must be maintained during the sealing process in order to maintain package sterility.

 

How Leaks Are Discovered


In determining leaks in these various types of packaging, there are several signs that may ring the alarm bells. In general, the process involves searching for abnormalities can be detected via sight or touch. These indications of leaks include mechanical defects, perforations, de-lamination, and swelling, flex cracks, and malformations.

 

For fine examination procedures microscopy, SLAM (scanning laser acoustic microscopy), SAM (scanning acoustic microscopy), and ultrasound may be used in addition to visual inspection. Fine examination is the preferred method of leak detection for issues that involve the seal of the packaging.

 

Leak detection testing focuses on using a chemical or gas in order to detect leaks. These techniques measure the escape or entry of liquids or gases that have been pressurised or evacuated via systems that are designed to contain the escaped cases or liquids.

 

Leak Detection Tests

● Air leak testing

● burst testing

● chemical etching

● compression testing

● Distribution testing

● Electesters

● Electroconductivity

● Helium leak testing

● Manganese ion testing

● Bubble-forming testing

Vacuum decay testing

 

For food companies that want to protect their brands, leak testing is an essential step in the packaging process. Sealtick offline standalone leak testers are the most cost effective solutions to avoid unsafe packaging that offer superior quick results. The leak detection equipment is also designed so that companies can introduce them to their existing QA/QC process. To learn more about the SealTick products, Call 03 9540 5100.