Retort and hot fill spouted pouches manufactured by Mondi North America have successfully completed hermetic seal integrity tests conducted by The National Food Laboratory LLC, an independent testing organization. The testing offers added assurance to food companies and co-packers that Mondi retort and hot fill pouches meet the highest standards for leak-proof, hermetically sealed performance.   

“The hermetic seal integrity test exposes pouches to extremely challenging conditions,” said Roger Vrooman, product development engineer, Mondi Jackson (Mo.). “Mondi’s successful test results should interest packaging managers responsible for a wide range of food products including baby foods and fruit purees.”

Mondi’s retort pouches and their contents are sterilized and remain stable on store shelves without the need for freezing or refrigeration. They are designed for packaging of such products as baby foods, soups, sauces and rice products. Mondi’s hot fill spouted pouches are typically used to package more acidic products such as apple sauce and fruit purees.   

Successful Testing
The hermetic seal integrity tests were conducted at The National Food Laboratory’s facility in Livermore, CA. A representative sample of Mondi retort spouted pouches with caps were filled with a low-acid broth and sterilized in a lab retort chamber. A small number of pouches were selected for an initial burst test; they showed no leakage after subjection to a strong vacuum of -20 inches of mercury (Hg).

A batch of 50 pouches then underwent immersion biotesting according to U.S. Food and Drug Administration guidelines. This involved submersion in a bacteria-filled solution followed by a two-week incubation period. The Mondi pouches showed no signs of swelling that would indicate bacterial contamination, confirming that the pouches had maintained their seal integrity.  
 
Mondi’s hot fill spouted pouches also underwent burst testing and immersion biotesting for hot fill applications. Pouch samples were filled with a high-acid solution that simulated the actual contents of hot fill applications, and then sterilized in a steam tunnel. The pouches completed the tests with no failures, verifying the pouches’ seal integrity.