The Time is Now to Switch to Vacuum Decay Testing

If you’re still testing food packaging with the bubble leak method, it might be time for an alternative. Compatibility with next-generation packaging materials is just one of the many advantages of the better option: vacuum decay testing.

An increasing clamor for sustainability in the industry is shaping the food packaging sector as well. The use of mono materials and more eco-friendly packaging addresses this demand, as does reducing waste through higher production efficiencies. These shifts are playing out alongside the growth of more stringent regulatory standards for food safety.

Understandably, such a complex and fast-evolving landscape has consequences for how the food industry tests container closure integrity. It’s becoming increasingly apparent that the traditional bubble leak method for verifying container closure integrity is falling short in a number of ways. Fortunately, vacuum decay testing has several advantages that make it a better fit for today’s processes.

It’s time for the food packaging industry to switch to vacuum decay testing. Failing to do so will doubtless have very real adverse effects on efficiencies. Here’s why.

The bubble leak and vacuum decay tests

The traditional bubble leak testing method for identifying leaks involves submerging a food package underwater and applying a vacuum. If there’s a leak, air escapes from the package, forming bubbles visible to the operator. This test has been popular for decades due to its simplicity and low upfront costs. It doesn’t require sophisticated equipment, making it a go-to choice for smaller operations and older production facilities.

Vacuum decay testing involves placing the package in a chamber with flexible membranes, creating a vacuum in the setup, and measuring its level over time. If the package has a leak, air or gas will escape from it and increase the pressure in the chamber. Sensitive pressure sensors pick up the measurable change in vacuum level, finding even the smallest leaks without damaging the package or causing waste. The method is useful for a variety of packages, especially in food packaging.

The disadvantages of bubble leak testing

While bubble leak testing is simple, it’s problematic in many ways:

Product loss
Bubble testing destroys the product, which means it can’t be sold, adversely impacting revenue. In addition to revenue loss, such waste is also increasingly probable as the industry switches to less water-resistant materials like paper-based packaging. Added waste might likely not comply with sustainability standards.

Inconsistent and subjective results
Because bubble leak testing is largely visual and manual, results are subjective. They can vary depending on the operator’s skill and attention, leading to potential quality issues and recall risks, which are expensive to rectify. Because the results are not objective, there’s no consistent standard for what qualifies as leak-free packaging. The package that one quality control inspector passes as having met standards might not always do so with another operator. The sensitivity of leak detection might also vary depending on the operator’s skill.

Labor and time-intensive
The manual nature of bubble leak testing slows production and requires dedicated staff, increasing labor costs and impacting productivity, especially when scaling up. Equally important, the bubble leak method involves taking the product out of the assembly line, a process that is incompatible with today’s high-speed production, which might churn out 60 to 120 packages a minute. Bubble leak methods are not easy to incorporate into automated workflows and delay production lines.

The advantages of vacuum leak testing

Vacuum leak testing offers many advantages over the traditional bubble leak equivalent:

Non-destructive
Unlike bubble leak testing, vacuum decay testing doesn’t require breaking or damaging the package, allowing manufacturers to test samples without losing sellable products.

Speed and possibility for automation
The vacuum decay process can be fully automated and integrated into high-speed production lines, providing rapid, reliable results with minimal human intervention. This is crucial for maintaining efficiency in large-scale operations.

Compatible with contemporary and future packaging
Vacuum decay testing works across various packaging materials, including flexible plastics, rigid containers, and the latest paper-based laminates, ensuring compatibility with current and next-generation packaging solutions.

Transitioning to vacuum decay testing

Switching to vacuum decay testing involves more than just buying new equipment; it requires a shift in quality assurance processes.

A checklist for manufacturers to follow:

Assess packaging materials
To ensure no unintended effects on the integrity of the package, evaluate how the testing method interacts with packaging materials, especially if you’re using innovative materials like compostable films or multi-layer laminates.

Plan for integration
Vacuum decay systems can plug and play and seamlessly integrate into existing production lines. Work with technology providers to customize the setup for your plant’s specific needs.

Check testing speed
Ensure the vacuum decay system can match or exceed the throughput of the current testing method to avoid bottlenecks.

Pay attention to training and management processes
Ensure operators and quality assurance teams undergo training to adapt to and fully leverage the capabilities of vacuum decay testing.

Evaluate sensitivity requirements
Determine the acceptable leak size threshold for your product so you can select a method with appropriate sensitivity levels.

Conduct a cost-benefit analysis
While the initial investment for vacuum decay testing might be higher, consider the long-term benefits — including reduced waste, better quality assurance, and compliance — which can outweigh traditional methods over time.

Switching to vacuum decay testing now is crucial to future-proof operations, maintain compliance, and support sustainable practices. With its ability to handle diverse packaging types, vacuum decay testing offers a long-term container closure integrity solution that adapts to both current needs and future trends.