As they take steps to improve speed and efficiency throughout their operations, processors can ill afford time and product lost on faulty products. That includes items in high-barrier vacuum packaging designed to protect fresh meat and poultry and extend its shelf life.
It’s not a perfect world, of course, and packaging isn’t always perfect. Materials differ in gauge and type. Formats have various advantages and drawbacks. Accidents happen, whether caused by humans or machines, and packaging is vulnerable to tears, punctures, improper sealing and other issues that impact integrity.
The cost of not taking steps to assess and address package integrity risk is high: leaky packages of fresh meat pose food safety hazards, dissatisfaction among foodservice and retail customers and real losses at the processing level that can include pulled product and reworked product.
That said, there are ways processors can minimize waste and rework resulting from package leaks.
Film schooled
Film choice and package formats are fundamental factors in guarding against leaks in vacuum packaging that can cause rework and loss. “As it relates to vacuum, there are all different types,” points out Sean Brady, market development manager and Cryovac vacuum packaging expert for the Sealed Air North America Food Care Division, Elmwood Park, New Jersey, citing vacuum skin, thermoform, barrier bags and more.
Christian Uebele, product market manager, thermoforming, for Multivac in Kansas City, Missouri, agrees that films are a starting point for integrity. “Producing a perfect package starts with the packaging materials and the application that fits all the product specifications. One of the more important factors in producing a perfect package is the packaging film itself,” he says.
In today’s manufacturing environment, realities like cost and the desire for more sustainable or less wasteful packaging have an impact on film use. “Today processors face increasing pressure to keep the cost of the package to a minimum, which cannot be ignored,” Uebele says.
As a result, some choices may be inviting challenges later in the process. “While this can create instant savings, it may also result in integrity issues with the formed pocket. The minimum film thickness required to produce the best package depends on the attributes of the product, desired package presentation and distribution chain,” Uebele explains.
The best solutions, he advises, include plug assist forming technology that precisely pushes film down into the pocket or positive forming technology that forms the softened film around the plug instead of it being formed into the pocket in order to produce the thickest film. After the package is formed, pockets can be inspected by a post forming leak detection system that, depending on the system, can be communicated to loaders, labelers and rejection stations downstream.
Also, while thinner packaging may be cheaper and use less material, there are other ways for vacuum packages to be both sustainable and high integrity. “We look all the time at the sustainability perspective and at better materials for seals and resilience. But from a waste perspective, the longer the shelf life, the better. The leaker side is a part of it but so is the spoilage rate at retail and at consumers’ homes. Protecting it through the whole value chain is part of our approach,” Brady says.
Process controls
The vacuum packaging process is another point that can make or break package integrity. “We are always trying to reduce and minimize waste on our lines through our simple but precise film guide systems and our consistent die lift systems that close our dies precisely,” reports Mike McCann, packaging specialist for Reiser, Canton, Massachusetts.
Montreal, Quebec-based TC Transcontinental uses ClearShield boneguard bags to minimize leakers from bones and rough handling. The bags also have a wide sealing range to ensure strength. “We spend a great amount of time helping train and educate our customers on how to recognize and identify leakers, and their source, so that online issues can be addressed to keep leakers to a minimum,” says Rebecca Casey, vice president of marketing and consumer market development with TC.
Seal systems are also integral to package integrity. “We use one seal system for all types of packages. A medical package leaker is critical as is any food item package to that customer and the end user,” Reiser’s McCann says, adding that Reiser has online seal integrity systems utilizing its partner JLS that provide an additional level of inspection with rejection and complete traceability. “We do this by using well proven componentry, and one control system.”
At Multivac, Uebele says technologies are in place to better load product and keep the flange clean for a strong seal, including loading grids that protect the flange from above, confirmation stations that fully open pockets to help operators put product in and flange cleaning stations that can be customized to sweep or blow product off the flange.
“The sealing process has its own set of challenges and the solutions are as varied as the product being packaged. The goal inside the sealing die is not only to seal the top and bottom films together, but may also be to modify the atmosphere in the package to extend the shelf life of the food inside,” Uebele explains. There are solutions, he adds, like supporting the flange of the package while it enters the die to prevent sagging packages.
“The package is sealed once specific oxygen or vacuum levels are reached. Active monitoring of the air being evacuated from the die ensures the package achieves the precise gas or vacuum level,” Uebele adds.
The eyes have it
On that point, performing the practical but fundamental step of monitoring is pivotal to preventing problems tied to leakages. Brady recommends regular visual assessments, continual audits and maintenance plans as a part of that stringent monitoring. “When it comes to air, which is what happens with a typical leaker, it’s hard to beat the human eye to see if it’s a regular leak or a micro-issue,” he says. A thorough audit can also determine if there are bad seals on machine or rough handling of the product, he notes.
Uebele agrees that keeping an eye on vacuum packaging and processes is important. “The integrity of a package requires that the entire packaging process is monitored and evaluated to confirm the optimal process is used for the specific application,” he says.
TC Transcontinental uses an in-house team, Customer Technical Support (CTS) Group to observe and then recommend right size and right spec packaging based on customer process and product for maximum performance. For high leaker pork cuts like butts and picnics the company designed its thin gauge ClearShield to address rough handling and product condition. “Our ClearShield bag can nearly eliminate bone puncture leakers while improving the gloss, clarity and overall retail appeal of those products,” Casey says. She adds that TC Transcontinental regularly schedules line evaluations and improvement initiatives with customers to ensure potential profit margin hits are kept to a minimum.