Plastic Can (Double-seam Metal End) Summary

Abrasion

Classification
  • A major defect if pronounced (A penetration deeper than the outer layer).
  • A minor defect if slight (A penetration only the outer layer).
Identification

This is a scratch through any of the layers of the plastic container.

Causes

The packages were manually scraped on the retort racks, other equipment or other packages.

Crushed

Classification
  • A major defect if affecting the double seam.
  • A minor defect if not affecting the double seam.
Identification

This is the alteration of the plastic container's original dimensions by force.

Causes

The packages were abused during on-line or post-process handling.

Cut (Fracture)

Classification
  • A critical defect.
Identification

This defect is a mechanical slash or slicing that penetrates the plastic container, causing a loss of hermatic integrity.

Causes
  1. The plastic container has contacted burrs or sharp corners on equipment.
  2. The packages were abused during on-line or post-process handling.
  3. The lack of flexibility and resiliency of the laminated container body to withstand the severe stresses encountered during double-seaming operation may lead to the fractures.

Delamination

Classification
  • A minor defect.
Identification

Delamination is a separation of the container laminate materials.

Causes
  1. The material bond strength is inadequate.
  2. The lack of flexibility and resiliency of the laminated container body to withstand the severe stresses encountered during double-seaming operation may result in delamination.

Double Seam Defects

Classification
  • A critical defect.
  • A major defect.
  • A minor defect
Identification

The same defects found in double seamed metal cans: AOAC Can Defects

Causes

Flexcracks

Classification
  • A minor defect.
Identification

Unintended matter was imbedded in the plastic body.

Causes
  1. Unintended impurites from plastic pallets entered into the injection/blow molding or thermoforming process for plastic containers.
  2. Over-processed and brurnt plastic residuals were carried over from previous processing operations.

Foreign Matter Inclusion

Classification
  • A minor defect.
Identification

Unintended matter was imbedded in the plastic body.

Causes
  1. Unintended impurites from plastic pallets entered into the injection/blow molding or thermoforming process for plastic containers.
  2. Over-processed and brurnt plastic residuals were carried over from previous processing operations.

Gels

Classification
  • Is considered a minor defect.
Identification

This is improperly processed plastic included in the plastic container material.

Causes

The settings for injection/blow molding or thermoforming of plastic containers were not correct.

Malformed

Classification
  • A major defect.
  • A minor defect.
Identification

This is the plastic container that does not conform to mold contours as designed, or material distribution that does not conform to specifications such as waves, thin spots or discontinuous layers.

Causes

The settings for injection/blow molding or thermoforming of plastic containers were not correct.

Puncture (Pinhole)

Classification
  • A critical defect.
Identification

This defect is a mechanical piercing that penetrates the package, causing a loss of hermatic integrity.

Causes
  1. The plastic container has contacted burrs or sharp objects on equipment.
  2. The packages were abused during on-line or post-process handling.

Swell (Swollen Package)

Classification
  • A critical defect.
Identification

The package bulges due to gas formation from bacterial contamination, or excess internal residual air.

Causes
  1. The food was underprocessed or contaminated during aseptic processing.
  2. The package material was not properly sterilized or was contaminated during aseptic processing.
  3. The package was overfilled or a proper vacuum was not drawn, which resulted in an improper thermal process.
  4. The food package was under-processed during thermal processing.
  5. There was insufficient chlorine in the cooling water.
  6. The package leaked after processing. 7.The post-process handling was too rough.