"Beware of little expenses; a small leak will sink a great ship." -Benjamin Franklin
Although rare, just one small leak can cause significant problems for a beverage brand. Leaking cans, or "leakers," as they are commonly called in the industry, have the potential to damage other products and ruin a brand's reputation. While it's easy to think it won't happen to you, you could see a leaking can issue at some point in your beverage career without the proper precautions. The good news is that learning more about leakers and what causes them can help you better understand and manage your beverage brand's overall can quality.
Don't Overlook Can Quality
When you consider the engineering feat that is the aluminum can, the processes required to manufacture and fill cans, and the large production volume of most can lines, it's a miracle leaking cans don't make their way onto store shelves more often. Can manufacturers pay meticulous attention to quality. A case in point is Ball, one of the world's largest beverage can manufacturers, that also designed and built the largest camera NASA has ever flown into space. But even the tightest manufacturing operations have a margin of error. One in 50,000 cans is defective right off the line, and that is before they are filled and seamed.
The stresses placed on cans change as they move through the production process and into storage, transport, and retail environments. Ultimately, it's the brand owner's responsibility to minimize the probability of leakers by defining and upholding quality standards at every stage of production. Controlling quality has become even more critical as we face an aluminum can shortage.
Your can quality can be significantly impacted by how you proactively protect your cans and how efficiently you investigate and respond to issues like leakers. Adam Smith, Regional Sales Manager at BevSource, encourages brand owners not to overlook what they can learn from looking into leakers.
"Leakers happen for a lot of different reasons. A calm, organized approach to investigating potential root causes often reveals several opportunities to tighten up and improve processes, quality, and efficiency," says Smith.
Leading Causes of Leakers
A leak happens anytime a substance that is supposed to be held within the can spills or seeps out. While the consequences are ultimately visible in the form of less-than-perfect products, the root causes of leakers can be complex. Here are some of the primary issues that lead to leakers:
Internal Liner Failure
An internal liner failure is when the liner that coats the inside of the can underperforms, allowing the liquid to eat through the aluminum and hit the outside surface of the can, where it can cause corrosion. This type of breakdown is commonly known as secondary corrosion and is the primary cause of leaking cans. The outer liner doesn’t prevent corrosion, but an external liner failure can expedite a leaking can problem.
External Liner Failure
Cans also have an exterior liner that needs to be strong enough to withstand contact from various sources throughout the journey from manufacturing to the consumer. Leaks from an internal or external liner failure can impact the outer packaging of any other products the liquid touches. Not every can supplier maintains the same quality standards. But, tools like the SpecMetrix® ACS coating thickness and film weight measurement system empower beverage makers to independently diagnose potential issues and ensure product packaging consistency.
Liner integrity issues can lead to corrosion that causes microscopic holes, called pinholes, to form in a can. With a pinhole leaker, you often see the liquid that's escaped, but it can be challenging to find the tiny hole it traveled through.
A seamer creates a continuous seam between the lid and the can, creating a tight seal for the contained product. If seaming equipment is misaligned or a foreign object is introduced into the process, the product may leak out of a weak or compromised seam.
Cans can also leak due to damage sustained in the warehouse or during transport. While it’s vital to palletize your products properly for maximum protection by using enough wrap and reinforcement, sometimes that isn’t enough. Damage to cans can happen more easily when the liner's integrity is compromised due to changes in pressure and pH caused by certain microorganisms. It’s difficult to overstate the importance of effectively rinsing your cans with properly pasteurized water. Any product left on the outside of the can could quickly start secondary corrosion.
Best Practices For Eluding Leakers
While many factors play into can quality, there are a few straightforward steps you can take to minimize the risk of long-term business and brand damage from leakers.
- Start With Quality. It's critical to vet your can supplier to understand their standards and history of upholding those standards for different product types. Vetting for quality is especially important when considering a supplier that is newer to the market or from a country where quality standards may differ from your specifications. It is also important when you're working with an innovative product or process that requires closer monitoring or tighter measurements.
- Investigate Efficiently. As Hannah Krieg, Lab Manager at The Lab, BevSource's pilot facility and full-service laboratory for innovative beverages, says, "An undiscovered leak can cause an undesired chain reaction. If one can at the top of a finished pallet is leaking because of an exterior liner issue, the damage will continue until you identify the source and uncover the cause.” That’s why she says it's essential to have a proactive process to quickly identify, investigate, and address any potential can issues.
How To Address A Leaker
- Review your warranty
Before producing your finished drink, can manufacturers and most contract packers require that you have a can warranty. Warranties are based on corrosion testing performed by the can manufacturer. A warranty means the seller promises the buyer that its cans and ends are free from defects and conform to a seller's specifications. If there is an issue, it can be resolved based on the detailed conditions and limitations outlined in the warranty. Know what's covered by your contract and what requirements you need to uphold to maintain your warranty. Many brand owners are surprised to learn that printing on a can or changing your liner material or formulation means the original can warranty is often no longer valid. Warranties also usually expire within a specified timeframe.
- Minimize immediate damage
Take apart pallets from the top down. Primary leakers will likely be found on the top of a pallet. Take apart any pallet with a leaker to identify the primary sources and gather and dispose of any wet products. Once a can has been exposed to the liquid, corrosion begins, so any damp product must go.
- Retrace your can journey
Follow your cans back to the start and investigate the manufacturing and filling lines to find any sharp objects that could be damaging your cans. Review the details of your manufacturing processes, from rinsing and packing procedures to the water chemistry on your pasteurizers. Identify anything that could compromise the end quality of your cans.
- Take a second look at your specifications
It's always a good idea to review metrics and requirements, like your dissolved oxygen (DO) specifications, with your co-packer. Krieg notes that most of the leakers she sees are related to improper dissolved oxygen levels in the cans. High oxygen levels contribute to elevated can corrosion and perforation risk.
Other can measures and specifications include:
- Corrosion Testing
- SpecMetrix Liner Testing
- Quality Assurance and Quality Control Checkpoints
- Seam Inspections
- Printing Processes
- Formulation Changes
- Liner Material Changes
Once you've completed your investigation and assessed your findings, you will have a solid case with accompanying data to use to address the issue and make the changes necessary to help ensure it doesn't happen again.
Learning from Leakers
No two leakers are the same. Every leaker you encounter is an opportunity to leverage the scientific process to learn more about the complex art and science required to make and package a beverage. With learning comes improvement.
For Krieg, the challenge is part of the reward. "Food and beverages are complex chemical matrixes," says Krieg. "There is no standard product in food science. Every product is unique and has different quality hurdles. That's what makes it exciting."
As with every aspect of beverage manufacturing, managing your can quality to avoid and mitigate damage from leakers is both an obligation and an opportunity.
"The brands who prioritize and strategize around quality are the ones most prepared to lead with innovation," says Smith. "You can't push against constraints you don't understand how to control."
Do you want to see how you can leverage quality as a competitive advantage for your beverage brand?