Food Packaging Industry Applications: Case Studies
The customer produces prepared meals that are packaged into two-well thermoform trays sealed at the outside edge and across the well partition with food-grade film. TME was asked to provide a seal strength test system that would provide information on which cell's seals will rupture first under stress, and also whether that rupture would occur at the partition or at the outside seal. The test system consisted of the TME BT-1000 Automated Package Tester, a sensor and inflation probe, and the Package-Port™ leak tight entry system. Valves built into the test probe enabled separate and concurrent inflation seal strength tests to be performed on each of the two wells. This system provided the customer with the necessary information quickly, repeatably and with no operator influence.
A manufacturer of soft food products needed a way to confirm the seal integrity of their two-up food cups of various sizes. The TME Solution chamber leak test system is provided with custom manufactured inserts designed to minimize the interstitial space (space surrounding the test item in the chamber) and thus maximize the sensitivity of the leak test. The system is designed to detect air leakage when a differential pressure is created on the test part inside this closed chamber. The test fixture is composed of a fixed base and cavity block mounted on a holding frame. An O-ring on the cavity block seals the tested part inside the fitted cavities. After the chamber is evacuated to the desired vacuum level, the vacuum is monitored. If air from the test part enters the test chamber a drop in vacuum indicates a leakage into the test part. The Solution leak tester detects this leakage of air ("vacuum decay"), thus indicating a leak. Interchangeable cavity blocks, manufactured to accommodate various sizes of product, were provided to the customer. These blocks fit into the holding frame in the fixed base of the fixture. Test parameters for each size of food cups can be stored in the test instrument for easy and quick retrieval, further increasing the range of use of the test system.
The customer manufactures cylindrical paper containers for perishable food. In order to maintain the quality of the food for its shelf life, specifications for the vent rate of gas through the cylinder had been determined by the manufacturer. The customer already had a fixture designed to hold the cylinder for testing, and TME was asked to provide a way to confirm that the manufactured cylinders met these vent rate specifications before filling and sealing. The TME Solution™ four port test instrument was configured to perform concurrent flow tests on four cylinders at a time. The cylinders, already sealed at one end, were sealed at the fixture and a flow test was performed. If the rate of flow of pressurizing gas through the permeable paper was above or below the acceptable range indicated by the customer's specifications, the container was rejected.
The customer produces a wide variety of food products, many of which are packaged into flexible PVC or PET pouches. The pouches are of various configurations, sizes and closures such as peelable or resealable. The need was for a quick, highly accurate seal strength test system that would accommodate this variety of primary packaging for use in audit tests. TME provided the customer with a system consisting of the TME BT-1000 Automated Package Tester, the patented Package-Port™ leak tight package entry system, and a restraining plate fixture. This system optimizes seal strength results by performing inflation pressure decay tests that reveal any weak areas of the package seal as well as the order in which the seals will open. Test data are maintained in the Datalog of the BT-1000 instrument. Statistical data analysis capability includes mean and standard deviation calculation as well as control chart development, which permit fast and accurate audit testing for lot disposition.
The customer's product consisted of ground coffee vacuum packed and sealed into small foil packages. Because of this packaging process, there was no "head space" (air or gas space inside the package) to facilitate vacuum decay testing, so a pressure decay chamber test was designed. The TME Solution Chamber Leak Test System is comprised of a pressure decay chamber fixture with a TME Solution single port pressure decay leak test instrument. This TME Solution chamber leak test system is designed to detect air leakage when a differential pressure is created on the part under test inside the closed chamber. If pressurized air from the chamber is forced into the vacuum-packed product, a drop in test chamber pressure indicates the leakage. The TME Solution leak tester detects this leakage of air ("pressure decay"), thus indicating a leak. The test fixture is designed with manual toggle clamps as a safety feature.