FP - Seal Defects (Blister)

Classification 

  • A major defect if the width of the continuous intact seal is reduced to less than 3 mm (3/32-inch).
  • A minor defect if there is 3 mm (3/32-inch) or more of continuous intact seal.

Identification 

A blister appears as a void within the bonded seal. A blister resembles a bubble or has a raised appearance in the sealed area of the retort pouch.

Causes 

Food, grease or other contaminants were present in the seal area during seal formation.