Food > Fish and Seafood > Product Inspection > Flexible Retort Pouch Defects Manual 

CHAPTER 7
DEFECT CATEGORIES

SECTION 7.4
DEFECT: COMPRESSED SEAL

CLASSIFICATION:

A compressed seal is considered a serious defect if:

1) there is visual evidence of seal overheating, such as bubbles or exposed foil; and
2) there is less than 3 mm (3/32-inch) of continuous "good" seal (non-delaminated area) remaining.

A compressed seal is considered a minor defect if:

1) there is some visual evidence of seal overheating, such as bubbles or exposed foil; and
2) there is more than 3 mm (3/32-inch) of continuous "good" seal (non-delaminated area) remaining.

DESCRIPTION:

A compressed seal is any separation of the laminated plies in the seal area. The material bond strength is questionable in the area of the defect.

If the delamination continues into the "body" of the pouch, assess the defect under DELAMINATION.

COMMON SOURCES:

1) The sealing bars were too hot during seal formation.

2) Material bond strength is inadequate.

Delamination and Bubbling of the Polyester Laminate

Polyester Laminate has Melted Due to Overheating of the Seal

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