Newsletter
In this issue, we present an overview of the major issues in on-line leak and seal inspection of packages in the food industry. Future issues will answer the most commonly asked questions by our readers and customers.

Not so long ago, the only shelf stable package for the food industry was the metal can. Inspecting the integrity of the cans is well established and has remained the same throughout the world for many years. Today, the marketplace has a variety more convenient flexible and shelf stable type packages and the requirements and approaches for inspecting these packages vary greatly.

Today, food processor, distributors and ultimately customers are putting increased pressure on the packaging manufacturer to provide a consistent quality product. This has led the industry to invest in systems that provide 100% inspection of the product as it is being manufactured.

Two types of defects reduce the quality of the finished product and hence consumer acceptability. The first type of defect is seal contamination due to food being caught in the seal area. This reduces the seal strength of the package and may result in potential microbial contamination of the product. Seal defects and surface scratches that cannot be detected by human visual inspection can be inspected by special vision systems. These vision systems, equipped with advanced diagnostics are an inspection tool to help run production lines with better efficiencies. The second type of defect is the presence of tiny holes in the package causing tiny leaks which often escape visual inspection. PTI, under the Wilco label, has developed a unique approach to detected tiny leaks in empty and filled containers.

It consists of a three step process:

The last step measures and records the differential expansion of each package with special dual action transmitters. This three-step test cycle is usually completed in 2-3 seconds, depending on the size of the package.

Uniformly well sealed packages exhibit identical physical behavior, enabling the system to accurately and repetitively separate good packages from poorly sealed or leaky ones.

The inspection concepts, described above, are used to inspect aseptic, retort and modified atmosphere packages. Similar systems are also in use for food pouches and pharmaceutical blisters, which were previously tested by destructive methods such as the water bath.

If you have any comments or want further information, contact at e-mail address: Raymond Scheire at 75773.3436@compuserve.com .

PTI, 145 Main Street, TUCKAHOE, NY 10707,USA
Phone: (914)-337-2005 Fax: (914)-337-8515